ELECTROPLATING 2011

1.
Design of experiments for statistical modeling and multi-response optimization of nickel electroplating process Original Research Article
Chemical Engineering Research and Design, Volume 89, Issue 2, February 2011, Pages 136-147
Maria Poroch-Seritan, Sonia Gutt, Gheorghe Gutt, Igor Cretescu, Corneliu Cojocaru, Traian Severin
Abstract
The central composite experimental design and response surface methodology have been employed for statistical modeling and analysis of the results dealing with nickel electroplating process. The empirical models developed in terms of design variables (current density J (A/dm2), temperature T (°C) and pH) have been found statistically adequate to describe the process responses, i.e. cathode efficiency Y (%), coating thickness U (μm), brightness V (%) and hardness W (HV). The graphical representations consisted of 2D contour plots and 3D surface plots have been used for exploring and analysis of response surfaces in order to identify the main, quadratic and interaction effects. The multi-response optimization of nickel electroplating process has been carried out by means of desirability function approach. To this end, a genetic algorithm has been used for mathematical optimization of the multi-response problem. The optimization algorithm has conducted to a set of equivalent solutions named Pareto optimal set. The confirmation runs have been employed in order to make a decision about the optimal solution approved by experiment. Thus, the optimum conditions of nickel electroplating has been defined in this work as J* = 5.35 (A/dm2), T* = 33.44 (°C) and pH* = 6.22 and respectively the responses confirmed by experiment were Y = 79.12 ± 0.18 (%), U = 52.77 ± 0.48 (μm), V = 26.12 ± 0.45 (%) and W = 371.6 ± 1.77 (HV). In such conditions the quality of nickel electroplating deposit was the best one in accordance with experimental results.
Keywords: Electroplating; Experimental design; Response surface method; Desirability function; Genetic algorithm

2.
Treatment of nanowaste via fast crystal growth: With recycling of nano-SnO2 from electroplating sludge as a study case Original Research Article
Journal of Hazardous Materials, In Press, Corrected Proof, Available online 16 September 2011
Zanyong Zhuang, Xinjiang Xu, Yongjing Wang, Yandi Wang, Feng Huang, Zhang Lin
Abstract
The treatment of industrial sludge containing amorphous/nanophase metal oxides or hydroxides is one of the vital issues in hazardous waste disposal. In this work, we developed a strategy to recycle nano-SnO2 from tinplate electroplating sludge. It revealed that the major components of this sludge were acid soluble Sn and Fe amorphous phases. By introducing NaOH as a mineralizer, a fast growth of amorphous Sn compound into acid-insoluble SnO2 nanowires was achieved selectively. Thus, the as-formed nano-SnO2 could be recycled via dissolving other solid compositions in the sludge by using acid. The role of NaOH on accelerating both the Oriented Attachment (OA) and Ostwald Ripening (OR) growth of SnO2 was discussed, which was regarded as a critical factor for treating the sludge. A pilot-scale experiment was conducted to treat 2.3 kg original sludge and the recycling of about 90 g nano-SnO2 was achieved. We anticipate this work can provide a good example for the recycling of valuable metals from industrial sludge containing fine metal oxides or hydroxides.
Keywords: Metals recovery; Tin oxides; Electroplating sludge; Fast crystal growth; Mineralization

3.
Fabrication of metallic microstructure on curved substrate by optical soft lithography and copper electroplating Original Research Article
Sensors and Actuators A: Physical, Volume 168, Issue 1, July 2011, Pages 105-111
Jongho Park, Hiroyuki Fujita, Beomjoon Kim
Abstract
Microfabrication of copper structures with a high aspect ratio was successfully performed on a curved substrate by optical soft lithography and metal electroplating. This fabrication method comprises mainly of three steps. Firstly, a flexible polymer photomask was fabricated by a direct metal transfer technique via two types of self-assembled monolayer treatments. Next, SU-8 micro patterns were fabricated on a curved glass substrate by optical soft lithography. Here, we utilised a mask with a microslit and a flexible polymer photomask. Lastly, copper electroplating was performed on the curved substrate using the SU-8 patterns as molds to form high-aspect-ratio copper structures. We confirmed that SU-8 microline patterns with an aspect ratio of over 2.5 were formed on the curved substrate. Subsequently, copper structures fabricated on the curved substrate with SU-8 micro patterns were acquired. The unconventional microfabrication technique introduced in this work can be used for the fabrication of 3-D high-aspect-ratio metallic microstructures on curved or nonplanar substrates.
Keywords: Microfabrication; Nonplanar substrate; Curved substrate; SU-8; Copper electroplating

4.
Application of a system dynamics approach for assessment of the impact of regulations on cleaner production in the electroplating industry in China Original Research Article
Journal of Cleaner Production, Volume 20, Issue 1, January 2012, Pages 72-81
Xiaoqing Dong, Chaolin Li, Ji Li, Wantao Huang, Jia Wang, Ruibin Liao
Abstract
Compared with pollution transfer, cleaner production (CP) is more effective to reduce heavy metal pollution in many less developed countries. However, it’s more difficult to develop an efficient policy to make enterprises to completely invest in CP. This paper analyses the effects of CP policies on investment decisions of firms using a dynamic systems model and by simulating a typical electroplating enterprise in Shenzhen, China. Results show that water price could be effective only when it is increased by a sufficient amount. For instance, only when it is increased directly from 2 to 8 CNY/m3 (0.3–1.2 USD/m3), or from 8 to 16 CNY/m3 (1.2–2.5 USD/m3), will an enterprise gradually increase CP investment from process modification to recovery technology. Increasing the metal utilization rate of CP standard-plating and surface finishing industry from its current value of 75%–85% would encourage an enterprise to add recovery technology. Uniform preferential tax rate and penalties for the three parts of CP do not affect investment decisions on CP. Using the same investment subsidy rate for the three parts of CP could be effective in promoting CP only if it is above 60%. The current emission standard of metal has played a role in promoting CP. A comparison of three possible strategies indicates that a distinct policy for the different parts of CP is the optimal policy combination. An overall investigation of typical enterprises based on the abovementioned framework is suggested to make more practical policies, which than can promote CP instead of pollution transfer.
Keywords: Cleaner production; Electroplating; System dynamics; Investment decisions

5.
The formation of micro/nanoparticles in laser-enhanced electroplating with continuous-wave and pulsed Nd-YAG laser interactions Original Research Article
Optics & Laser Technology, Volume 44, Issue 1, February 2012, Pages 169-176
Shiang-Hung Chen, Jehnming Lin
Abstract
The copper particles generated by the laser-enhanced electroplating method have been investigated in this study, and the results have been examined at various process conditions. The electrolyte jet of copper sulfate was impinged on a stainless steel electrode and irradiated with a Nd-YAG laser at continuous-wave (CW) and Q-switched output modes, respectively, to generate the particle size distribution from micro- to nano-scale.
According to the electrochemical dynamics theory, the mechanism of the proposed technique for the particles formation is mainly due to the thermal effects from the laser interaction in electroplating. In the experiments, the laser energy absorbed by the electrolyte jet and the temperature rise of the electrode during the laser radiation has been measured. In the numerical simulation, the temperature fields of the impinging jet of the laser nozzle were calculated. It shows that the growth of the particle is significantly corresponding to the laser power and pulse mode of the laser interaction.

6.
Rule of formation of aluminum electroplating layer on Q235 steel Original Research Article
Journal of Environmental Sciences, Volume 23, Supplement, June 2011, Pages S138-S141
Zhimin Ding, Qiuyuan Feng, Changbin Shen, Hong Gao
Abstract
Aluminum electroplating layer on Q235 steel in AlCl3-NaCl-KCl molten salt was obtained, and the rule of its nucleation and growth were investigated. The results showed that aluminum electroplating layer formed through nucleating and growing of aluminum particles, and thickened by delaminating growth pattern. At low current density, the morphology of aluminum particles took on flake-like, while at high current density they changed to spherical. The thickness of plating layer increases with increasing current density and electroplating time. The relationship between the plating thickness (δ) and electroplating time (t) or current density (i) can be expressed as δ = 0.28f137, and δ = 1.1i1-39.
Key words: molten salt; electroplating aluminum layer; nucleation and growth; formation mechanism

7.
Fabrication and characterization of micro-sized copper bump of multi-layer PCB by pulse-reverse electroplating Original Research Article
Current Applied Physics, Volume 11, Issue 1, Supplement, January 2011, Pages S289-S292
Hyun Seon Hong, Min Hye Seo, Sungkyu Lee, Soon Jik Hong, H.G. Suk, Jae-Hwan Ahn
Abstract
In this research, micro-sized copper bump for multi-layered printed circuit board (PCB) was successfully developed using pulse-reverse electroplating method. The electroplating parameters of current density, pulse-reverse ratio and brightener content were optimized for fabrication of suitable micro-bumps. The pulse-reverse electroplated micro-bumps were characterized using various analytical tools and techniques such as optical microscopy, scanning electron microscopy, atomic force microscopy and hydraulic bulge testing. Optical microscope and scanning electron microscope analysis results indicated good electroplating uniformity in the current density range of 1.4–3.0 A/dm2, pulse-reverse ratio of 1:1, and brightener concentration of 600 ppm.
Keywords: Copper bump; Multi-layered PCB; Pulse-reverse; Electroplating

8.
Electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy study of the corrosion behaviour of galvanized steel and electroplating steel Original Research Article
Applied Surface Science, Volume 257, Issue 8, 1 February 2011, Pages 3383-3387
M. Lebrini, M. Traisnel, L. Gengembre, G. Fontaine, O. Lerasle, N. Genet
Abstract
The efficiency of a formula containing 2-{(2-hydroxyethyl)[(4-methyl-1H-1,2,3-benzotriazol-1-yl)methyl]amino}ethanol (tolyltriazole) and decanoic acid as corrosion inhibitor for galvanized steel and electroplating steel in aqueous solution have been determined by electrochemical impedance spectroscopy (EIS) techniques. The experimental data obtained from this method show a frequency distribution and therefore a modelling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The corrosion behaviour in the presence of different concentration of decanoic acid (DA) in the formula was also investigated by EIS. Results obtained reveal that, the formula is a good inhibitor for galvanized steel and electroplating steel in aqueous solution, the better performance was obtained in the case of galvanized steel. The ability of the inhibitor to be adsorbed on the surface was dependent on the nature of metal. X-ray photoelectron spectroscopy surface analysis with inhibitor shows that it's chemisorbed at the galvanized and electroplating steel/aqueous solution interface.
Keywords: Tolyltriazole; Decanoic acid; Corrosion inhibitors; Galvanized steel; Electroplating steel; Aqueous solution; X-ray photoelectron spectroscopy

9.
Function and mechanism of supercritical carbon dioxide emulsified electrolyte in nickel electroplating reaction Original Research Article
Surface and Coatings Technology, Volume 205, Issues 13-14, 25 March 2011, Pages 3890-3899
Tso-Fu Mark Chang, Masato Sone
Abstract
Physical properties of supercritical carbon dioxide emulsion (Sc–CO2–E) were controlled to evaluate the effects on properties of nickel film electroplated. Additive-free Watts bath was used to study sole-effect of Sc–CO2–E on nickel electroplating reaction. Experimental pressure, volume fraction of CO2 and surfactant were adjusted to control physical properties of Sc–CO2–E. Influence of current density was also studied. Surface roughness (Ra) was found to decrease with increase in pressure, volume fraction of CO2, volume fraction of surfactant and current density. Reduction in Ra was believed to be caused by improved homogeneity of Sc–CO2–E, enhanced desorption of hydrogen bubbles from surface of cathode, and increased nickel nuclei density. Grain refinement was observed when increasing pressure, volume fraction of CO2 and surfactant, which was believed to be caused by periodic plating characteristic of electroplating with Sc–CO2–E. On the other hand, grain coarsening was observed with increase in current density.
Keywords: Nickel electroplating; Supercritical carbon dioxide emulsion; Additive-free Watts bath; Pressure effect

10.
Micromachined anti-scatter grid fabricated using crystalline wet etching of (1 1 0) silicon and metal electroplating for X-ray imaging Original Research Article
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Volume 652, Issue 1, 1 October 2011, Pages 846-849
Dae-Hun Jeong, Jae Myung Kim, Do Young Noh, Kwang Hyun Kim, Jong-Hyun Lee
Abstract
Two-dimensional micromachined anti-scatter grids were fabricated using MEMS technology, including crystalline wet etching of (1 1 0) silicon and metal electroplating for X-ray imaging. The core sizes of the square grids were 100, 200, and 300 μm with 2.2 mm height and 50 μm septa thickness. To prepare the etch mask for crystalline wet etching, silicon nitride was deposited using low pressure chemical vapor deposition (LPCVD). The grid patterns, which are aligned parallel to the vertical (1 1 1) plane of the (1 1 0) silicon, were transferred from the photomask onto the photoresist using deep ultraviolet (DUV) photolithography, and consecutively onto the silicon nitride using reactive ion etching (RIE). A (1 1 0) silicon substrate was then etched in a tetramethyl ammonium hydroxide (TMAH) solution to form a skeleton for the septa structure. Chrome was sputtered to provide a seed layer for nickel electroplating, where nickel grows on the sidewalls of the skeleton of the septa structure. Finally, two-dimensional septa with various grid ratios were constructed by cross-stacking several layers of the patterned (1 1 0) silicon wafer. Anti-scattering ability was experimentally characterized in terms of X-ray transmission by one-dimensional scanning of incident angle.
Keywords: X-ray imaging; Micromachined anti-scatter grid; Micromachining; (1 1 0) Silicon; Crystalline wet etching; Electroplating

11.
Electrolytic tilt sensor fabricated by using electroplating process Original Research Article
Sensors and Actuators A: Physical, Volume 167, Issue 1, May 2011, Pages 1-7
Jae Hyoung Lee, Seung S. Lee
Abstract
This paper proposes new electrolytic tilt sensor fabricated by MEMS process especially using electroplating process to form vertical electrodes each of which is connected to planar electrode. Comparing with conventional electrolytic tilt sensors having difficulty in manufacturing in small size, the present tilt sensor can be manufactured in small size, particularly in very small height, having comparable performance, thus resulting in mass production possible, while still having a variety of manufacturing in higher height which is possible using electroplating process. In order to perform the electroplating process, an assembly of SU-8 polymer and PDMS was used as electroplating mold, former not being removed to form outer wall of sensor cavity but latter being removed to make a cavity in which electrolytic solution is contained. The nonzero null output voltage offset has minimum value in the range of 100–800 Hz of the frequency of alternating input voltage source. Analytically derived equation and experiments to examine how the sensor cavity size affects the performances confirmed that smaller the cavity diameter D, the smaller sensitivity but larger angle range. Compared to commercial electrolytic tilt sensor products, the fabricated tilt sensor has comparable performances such as angle range of about ±40°, especially linear range of about ±10°, sensitivity of 4.4 V/° in case of Vin = 1 V (rms), and resolution of 0.5 arc min.
Keywords: Electrolytic tilt sensor; Electroplating; SU-8; PDMS; MEMS

12.
The characteristics of chromized 1020 steel with electrical discharge machining and Ni electroplating pretreatments Original Research Article
Applied Surface Science, Volume 257, Issue 8, 1 February 2011, Pages 3529-3537
Ching-Yuan Bai, Jeou-Long Lee, Tse-Min Wen, Kung-Hsu Hou, Min-Sheng Wu, Ming-Der Ger
Abstract
A uniform and continuous chromized coating on AISI 1020 steel is produced by low-temperature pack chromization (LTPC) with electrical discharge machining and Ni electroplating pretreatments. The anticorrosive performance of the chromized steels is investigated in a 0.5 M H2SO4 solution at room temperature. The testing results indicate that the chromized specimen with electrical discharge machining and Ni electroplating pretreatments exhibits the lowest corrosion current density, 2.16 × 10−8 A cm−2, among the tested specimens. The corrosion resistance of all tested specimens are in the order of bare 1020 < 1020-Cr(700-2) < 1020-Ni–Cr(700-2) < 1020-EDM-Ni–Cr(700-2). Moreover, the 1020-Ni–Cr(700-2) specimen have the best conductivity as a result of the less amount of oxides in the superficial coating.
Keywords: AISI 1020 steel; Low-temperature pack chromization; Electrical discharge machining; Electroplating; Corrosion current density

13.
Facile synthesis and electromagnetic wave absorption properties of magnetic carbon fiber coated with Fe–Co alloy by electroplating Original Research Article
Journal of Alloys and Compounds, Volume 509, Issue 14, 7 April 2011, Pages 4726-4730
Lei Wang, Fang He, Yizao Wan
Abstract
Magnetic carbon fiber coated with Fe–Co alloy was prepared by electroplating at 25 °C for 5 min. The obtained magnetic coatings show sheet-like morphology and the crystal structure of the uniform coating is Co3Fe7 with a thickness of about 0.5 μm. The saturation magnetization of the magnetic carbon fiber reaches 31.5 emu/g with a coercivity of 87.1 Oe. The complex permittivity and permeability of magnetic carbon fiber/paraffin (30 wt%) composite were measured in the 2–18 GHz frequency range. The reflection loss below −10 dB covers the whole frequency range while below −20 dB the absorption frequency bandwidth is 6.8 GHz, and the minimum value is −48.2 dB at a coating thickness of 1.7 mm. Magnetic carbon fiber exhibits excellent electromagnetic wave absorption properties.
Keywords: Coating materials; Alloy electroplating; Fe–Co alloy; Carbon fiber; Electromagnetic wave absorption

14.
Room temperature mass production of carbon nanotube field emission micro-cathode arrays using electroplating of a CNT/Ni composite followed by micro-machining Original Research Article
Vacuum, Volume 85, Issue 8, 1 February 2011, Pages 827-832
Min Deng, Guifu Ding, Yan Wang, Xuemei Cui, Hong Wang, Faheng Zang, Huiqing Wu
Abstract
A room temperature fabrication method for the mass production of carbon nanotube (CNT) field emission micro-cathode arrays is reported. The technique combines electroplating of a CNT/Ni composite and micro-machining. This method combines the advantages of direct growth and screen printing conventionally used to fabricate such structures and avoids their disadvantages. Due to its integration and room temperature processing, the technique is proven to be advantageous in mass production and low cost. Results of field emission testing show that the CNT micro-cathodes have excellent field-emission properties, such as high current density (15.7 mA/cm2), field enhancement factor (2.4 × 106/cm), and good stability (109 h for 10% degradation of current density from 400 μA/cm2).
Keywords: Carbon nanotube; Electroplating; Micro-machining; Micro-cathode; Field emission

15.
A variable hydrophobic surface improves corrosion resistance of electroplating copper coating Original Research Article
Applied Surface Science, Volume 257, Issue 13, 15 April 2011, Pages 5524-5528
Xiuqing Xu, Liqun Zhu, Weiping Li, Huicong Liu
Abstract
In this paper, Cu/liquid microcapsule composite coating was prepared by electroplating method. And a variable hydrophobic surface was obtained due to the slow release of microcapsules and the rough surface. The hydrophobic property and corrosion resistance of the composite was investigated by means of water contact angle instrument and electrochemical technique, respectively. The results suggest that the contact angle (CA) of composite increases gradually with the increasing storing time, and the stable super-hydrophobic property was exhibited after storing in air for 15 days. Meanwhile, the excellent corrosion resistance was displayed, which could be ascribed to the good stability of hydrophobic film on composite surface.
Keywords: Electroplating; Super-hydrophobic; Copper; Microcapsule; Corrosion resistance

16.
Electroplating formation of Al–C covalent bonds on multiwalled carbon nanotubes Original Research Article
Synthetic Metals, Volume 161, Issues 3-4, February 2011, Pages 208-212
Kang Pyo So, Chandan Biswas, Seong Chu Lim, Kay Hyeok An, Young Hee Lee
Abstract
We focus on the formation of strong aluminum (Al)–carbon nanotube (CNT) covalent bonds on the CNT walls without deteriorating CNTs for mechanically strong composite. We propose a simple electroplating method to realize Al–CNT covalent bonds on the CNT wall. The CNT electrode was formed on the Cu collector as a cathode and separated from the anode by an organic separator in tetrahydrofuran (THF) under Ar atmosphere. The Al deposition started to increase rapidly at above Al reduction potential. The formation of Al–C covalent bonds was confirmed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Charge transfer from CNTs to Al and generation of D-bands in Raman spectroscopy further confirmed the formation of Al–C covalent bonds.
Keywords: Carbon nanotube; Aluminum; Covalent bond; Composite; Electroplating

17.
Effects of supporting electrolytes on copper electroplating for filling through-hole Original Research Article
Electrochimica Acta, Volume 56, Issue 17, 1 July 2011, Pages 5954-5960
Chien-Hung Chen, Chun-Wei Lu, Su-Mei Huang, Wei-Ping Dow
Abstract
The filling of micron through-holes (THs) in a printed circuit board (PCB) by copper electroplating was investigated in this study. The role of supporting electrolytes, such as H2SO4, Na2SO4 and K2SO4, was explored using practical TH filling plating and linear-sweep voltammetry (LSV) analysis of plating solutions. The copper could selectively fill THs using one organic additive, namely, tetranitroblue tetrazolium chloride (TNBT), as an inhibitor. The inhibiting strength of TNBT depended on the supporting electrolytes. Although H2SO4 could enhance the inhibiting strength of TNBT, it also decreased the filling capability of the copper plating solution; Na2SO4 and K2SO4 did not enhance the inhibiting strength of TNBT but they increased the filling capability of the copper plating solution. Additionally, the protons could chemically interact with TNBT to form precipitate, whereas sodium and potassium ions did not easily interact with TNBT. The filling capability of the copper plating solution using Na2SO4 and K2SO4 as supporting electrolytes could be greatly improved by adding a small amount of bis(3-sulfopropyl)-disulfide (SPS) and poly(ethylene glycol) (PEG) with a molecular weight of 600.
Keywords: Through-hole filling; Copper electroplating; Supporting electrolyte

18.
Preparation and characterization of Nb2O5–Al2O3 composite oxide formed by cathodic electroplating and anodizing
Materials Science and Engineering: B, Volume 176, Issue 18, 15 November 2011, Pages 1505-1508
Joo-Hee Jang, Tae-Yoo Kim, Nam-Jeong Kim, Chang-Hyoung Lee, Eun-Mi Park, Chan Park, Su-Jeong Suh
Abstract
Al foil was coated with niobium oxide by cathodic electroplating and anodized in a neutral boric acid solution to achieve high capacitance in a thin film capacitor. X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) revealed the niobium oxide layer on Al to be a hydroxide-rich amorphous phase. The film was crystalline and had stoichiometric stability after annealing at temperatures up to 600 °C followed by anodizing at 500 V, and the specific capacitance of the Nb2O5–Al2O3 composite oxide was approximately 27% higher than that of Al2O3 without a Nb2O5 layer. The capacitance was quite stable to the resonance frequency. Overall, the Nb2O5–Al2O3 composite oxide film is a suitable material for thin film capacitors.
Keywords: Thin film capacitor; Cathodic electroplating; Anodizing; Nb2O5–Al2O3 composite oxide

19.
High aspect ratio nanostructuring by high energy electrons and electroplating Original Research Article
Microelectronic Engineering, Volume 88, Issue 8, August 2011, Pages 2259-2262
Sergey Gorelick, Joan Vila-Comamala, Vitaliy A. Guzenko, Christian David
Abstract
Due to the ability of 100 keV electrons to penetrate deep into resist with little scattering, we were able to directly write various dense and high aspect ratio nanostructures in up to 1.65 μm thick layers of poly(methyl methacrylate) (PMMA) resist. The PMMA molds produced by electron beam lithography were developed using a high contrast developer. The molds were used to transfer the pattern into metallic nanostructures by filling the developed trenches with Au by electroplating. By exposing lines narrower than the target width, we observed improved process latitude and line width control. The obtained aspect ratios of the dense structures are nearly 17 in 1.1 μm PMMA layers and >13 for structures electroplated into these PMMA molds. The fabrication method was successfully applied to produce Au diffractive X-ray Fresnel zone plates of exceptionally good quality with 70 nm outermost zones using 1.1 μm thick PMMA mold. In addition, we also produced regular arrays of high aspect ratio and dense Au nanorods and high aspect ratio split ring resonators with line widths down to 65 nm and with heights up to 1.5 μm.
Keywords: High aspect ratio; PMMA; Electron beam lithography; X-ray optics; Nanorod; Split-ring resonator; Au electroplating

20.
Fabrication and electromagnetic properties of bio-based helical soft-core particles by way of Ni–Fe alloy electroplating Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 323, Issue 24, December 2011, Pages 3223-3228
Mingming Lan, Deyuan Zhang, Jun Cai, Wenqiang Zhang, Liming Yuan
Abstract
Ni–Fe alloy electroplating was used as a bio-limited forming process to fabricate bio-based helical soft-core ferromagnetic particles, and a low frequency vibration device was applied to the cathode to avoid microorganism (Spirulina platens) cells adhesion to the copper net during the course of plating. The morphologies and ingredients of the coated Spirulina cells were characterized using scanning electron microscopy and energy dispersive spectrometer. The complex permittivity and permeability of the samples containing the coated Spirulina cells before and after heat treatment were measured and investigated by a vector network analyzer. The results show that the Spirulina cells after plating keep their initial helical shape, and applying low frequency vibration to the copper net cathode in the plating process can effectively prevent agglomeration and intertwinement of the Spirulina cells. The microwave absorbing and electromagnetic properties of the samples containing the coated Spirulina cells particles with heat treatment are superior to those samples containing the coated Spirulina cells particles without heat treatment.
Keywords: Bio-limited forming; Bio-based helical particle; Ni–Fe alloy electroplating; Heat treatment; Electromagnetic property

21.
Modeling of galvanostatic pulse and pulsed reverse electroplating of gold Original Research Article
Electrochimica Acta, Volume 56, Issue 9, 30 March 2011, Pages 3328-3333
Zhengwei Liu, Alan C. West
Abstract
A mathematical model of galvanostatic pulse and pulsed reverse electroplating of gold on a rotating disk electrode is presented. Using experimental polarization curves, dc current efficiencies, and literature-reported diffusion coefficients, model parameters are estimated. An accurate prediction of current efficiency by the on–off pulse-plating model was confirmed by experimental measurement. The current efficiency of pulse-reverse plating at relatively low waveform frequency is also successfully predicted, with less agreement at higher frequencies, presumably due to the simplified approach that the model employs to treat the complex set of reactions that occur during the anodic portion of the wave. When the reduction of adsorbed gold species produced during the oxidation portion of the pulse is included, improved agreement between experiment and theory is obtained.
Keywords: Electroplating; Simulation; Gold; Pulsed reverse plating; Hydrogen evolution

22.
Copper electroplating into deep microvias for the “SiP” application Original Research Article
Microelectronic Engineering, Volume 88, Issue 5, May 2011, Pages 749-753
Cheng Fang, Alain Le Corre, Dominique Yon
Abstract
In order to anticipate the further demands of miniaturization and integration of “System-in-Package”, the technology of 3D through-silicon-vias (TSVs) has been developed at NXP Semiconductors. The sputtering and the electroplating have been chosen for realize respectively a copper seed layer and a thick copper deposition inside 75 μm wide and hundreds micrometer deep microvias. The microvias, for an aspect-ratio (AR) up to 2.3, can be successfully covered by a sputtered 3 μm thick copper layer. To achieve a thick microvia filling, the pulsed current is preferred and a perpendicular electrolyte flow is critical. With an 11 μm thick patterned photoresist mask on the field, the 75 μm diameter and 180 μm deep microvias can be more-than-the-half filled using the “superfilling” recipe when the field depositing layer reaches the mask level. Such partially filled microvias exhibit excellent electrical resistances within the range of 4 mΩ.
Keywords: SiP; Copper seed coating; Copper electroplating; Microvias

23.
Properties of Al2O3 nano-particle reinforced copper matrix composite coatings prepared by pulse and direct current electroplating Original Research Article
Materials & Design, Volume 32, Issues 8-9, September 2011, Pages 4478-4484
Saeed Reza Allahkaram, Setareh Golroh, Morteza Mohammadalipour
Abstract
Cu–Al2O3 nano-composite coatings have high potential for use in applications in which high mechanical properties together with high corrosion resistance are required. In the present study it is intended to produce copper nano-alumina composite coatings with various nano-alumina contents in order to investigate the effect of alumina reinforcement particles on corrosion resistance and mechanical properties such as hardness and wear resistance. The composite coatings were deposited using direct current (DC) and pulse current (PC) plating. The microstructures of the coatings produced from both methods were examined via scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The wear behaviors, micro hardness, coating thickness, corrosion rate and coating porosity were examined using appropriate methods. Compared to DC deposition, PC plating facilitated higher amounts of particle incorporation with more uniform distribution. The results indicated that the mechanical properties of the applied coatings with incorporated nano-alumina reinforcement were far more superior as compared to its own matrix as well as non-composite copper coatings. It was also found out that increasing the amount of nano-alumina content in the coating, led to enhanced general properties of the coatings.
Keywords: A. Metal matrix composite; C. Electroplating; E. Mechanical properties

24.
Biosorption of Ni(II) from electroplating wastewater by modified (Eriobotrya japonica) loquat bark Original Research Article
Journal of Saudi Chemical Society, In Press, Corrected Proof, Available online 18 July 2011
Nidá M. Salem, Akl M. Awwad
Abstract
Biosorption of nickel ions from aqueous solutions by modified loquat bark waste (MLB) has been investigated in a batch biosorption process. The biosorbent MLB was characterized by FTIR analysis. The extent of biosorption of Ni(II) ions was found to be dependent on solution pH, initial nickel ions concentration, biosorbent dose, contact time, and temperature. The experimental equilibrium biosorption data were analyzed by three widely used two-parameters Langmuir, Temkin and Freundlich isotherm models. Langmuir and Temkin isotherm models provided a better fit with the experimental data than Freundlich isotherm model by high correlation coefficients R2. The maximum adsorption capacity was 27.548 mg/g of Ni(II) ions onto MLB. The thermodynamic analysis indicated that the biosorption behavior of nickel ions onto MLB biosorbent was an endothermic process, resulting in higher biosorption capacities at higher temperatures. The negative values of ΔG° (−5.84 kJ/mol) and positive values of ΔH° (13.33 kJ/mol) revealed that the biosorption process was spontaneous and endothermic. Kinetic studies showed that pseudo-second order described well the biosorption experimental data. The modified loquat bark (MLB) was successfully used for the biosorption of nickel ions from synthetic and industrial electroplating effluents.
Keywords: Biosorption; Nickel; Modified loquat bark; Adsorption isotherms; Adsorption kinetic

25.
Integration of electroplating process design and operation for simultaneous productivity maximization, energy saving, and freshwater minimization Original Research Article
Chemical Engineering Science, In Press, Corrected Proof, Available online 24 September 2011
Chaowei Liu, Chuanyu Zhao, Qiang Xu
Abstract
Electroplating industry annually produces numerous plated workpieces for U.S. pillar industries. However, it is also a major environment polluter in forms of wastewater, sludge, and spent solution. Thus, waste source reduction for the electroplating industry is a must. In practice, when productivity and energy use efficiency are also taken into account, the design and operation of an electroplating process become very complicated and need an in-depth study. In this paper, productivity maximization, energy saving, and freshwater/wastewater minimization are simultaneously addressed for the optimal design and operation of electroplating processes, which generates a triple-objective mixed-integer dynamic optimization (MIDO) model. The MIDO model is iteratively solved by a developed methodology to obtain the 3D Pareto frontier of the optimization problem, which provides important technical supports for the design and operation of electroplating processes. The efficacy has been demonstrated with a case study on an electroplating process.
Keywords: Hoist scheduling; Water network synthesis; Energy saving; Optimization; MINLP; Pareto frontier

26.
Simultaneous mixed-integer dynamic optimization for environmentally benign electroplating Original Research Article
Computers & Chemical Engineering, Volume 35, Issue 11, 15 November 2011, Pages 2411-2425
Chaowei Liu, Jie Fu, Qiang Xu
Abstract
Hoist scheduling, especially cyclic hoist scheduling (CHS), is used to maximize the manufacturing productivity of electroplating processes. Water-reuse network design (WRND) for the electroplating rinsing system targets the optimal water allocation, such that fresh water consumption and wastewater generation are minimized. Currently, there is still a lack of studies on integrating CHS and WRND technologies for electroplating manufacturing. In this paper, a multi-objective mixed-integer dynamic optimization (MIDO) model has been developed to integrate CHS and WRND technologies for simultaneous consideration of productivity and water use efficiency for environmentally benign electroplating. The orthogonal collocation method on finite elements is employed to convert the MIDO problem into a mixed-integer nonlinear programming (MINLP) problem. The efficacy of the methodology is demonstrated by solving a real electroplating example. It demonstrates that the computational methods of production scheduling, process design, and dynamic optimization can be effectively integrated to create economic and environmental win–win situations for the electroplating industry.
Keywords: Hoist scheduling; Water-reuse network design; Environmentally benign manufacturing

27.
Hydration and leaching characteristics of cement pastes made from electroplating sludge Original Research Article
Waste Management, Volume 31, Issue 6, June 2011, Pages 1357-1363
Ying-Liang Chen, Ming-Sheng Ko, Yi-Chieh Lai, Juu-En Chang
Abstract
The purpose of this study was to investigate the hydration and leaching characteristics of the pastes of belite-rich cements made from electroplating sludge. The compressive strength of the pastes cured for 1, 3, 7, 28, and 90 days was determined, and the condensation of silicate anions in hydrates was examined with the 29Si nuclear magnetic resonance (NMR) technology. The leachabilities of the electroplating sludge and the hardened pastes were studied with the multiple toxicity characteristic leaching procedure (MTCLP) and the tank leaching test (NEN 7345), respectively. The results showed that the electroplating sludge continued to leach heavy metals, including nickel, copper, and zinc, and posed a serious threat to the environment. The belite-rich cement made from the electroplating sludge was abundant in hydraulic β-dicalcium silicate, and it performed well with regard to compressive-strength development when properly blended with ordinary Portland cements. The blended cement containing up to 40% the belite-rich cement can still satisfy the compressive-strength requirements of ASTM standards, and the pastes cured for 90 days had comparable compressive strength to an ordinary Portland cement paste. It was also found that the later hydration reaction of the blended cements was relatively more active, and high fractions of belite-rich cement increased the chain length of silicate hydrates. In addition, by converting the sludge into belite-rich cements, the heavy metals became stable in the hardened cement pastes. This study thus indicates a viable alternative approach to dealing with heavy metal bearing wastes, and the resulting products show good compressive strength and heavy-metal stability.

28.
One-step metal electroplating and patterning on a plastic substrate using an electrically-conductive layer of few-layer graphene Original Research Article
Carbon, In Press, Corrected Proof, Available online 17 September 2011
Taeseon Hwang, Joon Suk Oh, Jung-Pyo Hong, Gi-Yong Nam, Ah-Hyun Bae, Sang-Ik Son, Geun-Ho Lee, Hak-Kyung Sung, Youngkwan Lee, Jae-Do Nam
Abstract
Few-layer graphene (FLG) was investigated as an electrically-conductive interleaf layer for one-step electroplating and patterning of metal on nonconductive polymer substrates without using multiple and toxic pretreatment processes in traditional electroplating. An individual FLG (5–10 nm of thickness with 6.4% of oxygen content) was obtained by expanding graphite with microwave followed by exfoliating the expanded graphite with sonication in N-methyl-pyrrolidone. Stacking FLG in the in-plane direction, a robust FLG film was obtained by the vacuum-assisted filtering and drying methods, and transferred to a polyethylene terephthalate (PET) substrate via an intermediate transfer to the water surface. The sheet resistance of the FLG film on the PET substrate was 0.9 kΩ/sq with a thickness of 80 nm and the root-mean-square roughness of 29 nm. In the electroplating of nickel on the FLG film, hemisphere-shape metal seeds appeared in the early stage of electroplating and they subsequently grew up to 200–480 nm, which became connected to form a continuous nickel layer. The thickness of the continuous nickel layer increased linearly with electroplating time. The developed electroplating method demonstrated its capability of selective patterning on nonconductive substrates using a simple masking technique.

29.
Microelectrode arrays for electroanalytical sensing: Comparison of electroplating and electron-beam metallisation
Electrochemistry Communications, Volume 13, Issue 5, May 2011, Pages 414-417
Alice Delcourt Lançon, Ritu Kataky, David Wood, Andrew J. Gallant
Abstract
This paper demonstrates the differences in electrochemical response obtained by two distinct methods of gold microelectrode array fabrication. An array of 306 gold recessed microelectrodes (45 μm in diameter) was fabricated using lithography, metallisation and oxygen plasma treatment processes. The microelectrodes characterised using cyclic voltammetry and AFM showed a marked change in surface roughness from 0.88 nm to 9.76 nm by using electroplating metallisation. This increase resulted in a substantial improvement in the MEA activity while maintaining the behaviour of the microelectrode array; a finding that indicates the cheaper electroplating technique is preferable for producing sensitive and reproducible MEAs.
Keywords: Microelectrode; Array; Metallisation; Roughness; Atomic Force Microscopy

30.
Sorption studies of Cu(II) on gooseberry fruit (emblica officinalis) and its removal from electroplating wastewater Original Research Article
Desalination, Volume 277, Issues 1-3, 15 August 2011, Pages 390-398
Rifaqat Ali Khan Rao, Shaista Ikram
Abstract
The sorption of Cu(II) onto waste residue left after extraction of juice from Indian gooseberry (Amla) fruit (Emblica officinalis) was studied. Equilibrium isotherms, kinetic data and thermodynamic parameters have been evaluated. Equilibrium data agreed well with Langmuir, Freundlich, Temkin and Dubinin–Radushkevich (D–R) isotherm models. The kinetic data followed pseudo-second-order model and it was found that intra-particle diffusion was not the sole rate-controlling factor. Gibbs free energy showed spontaneous process for all interactions. The breakthrough and exhaustive capacities were found to be 4.0 and 24.0 mg/g respectively. Emblica officinalis was shown to be a promising sorbent for Cu(II) removal from aqueous solutions. The practical utility of the sorbent has been demonstrated by achieving 97.60% removal of Cu(II) from electroplating wastewater by column process.

31.
Sorption of heavy metals from electroplating effluent using immobilized biomass Trichoderma viride in a continuous packed-bed column Original Research Article
International Biodeterioration & Biodegradation, Volume 65, Issue 8, December 2011, Pages 1133-1139
Rajender Kumar, Divya Bhatia, Rajesh Singh, Suman Rani, Narsi R. Bishnoi
Abstract
The sorption of heavy metals ions by immobilized Trichoderma viride biomass in a packed-bed column was studied. Fungal biomass T. viride was immobilized to Ca-alginate used for removal of Cr(VI), Ni(II) and Zn(II) ions from synthetic solutions and electroplating effluent. The experiments were conducted to study the effect of important design parameters such as bed height, flow rate and initial concentration of metal ions. The maximum sorption capacity was observed at flow rate 5 ml/min, bed height 20 cm and metal ions concentration 50 mg/L with immobilized biomass. Whereas, breakthrough time and saturation time decreased with increase flow rate and metal ions concentration and an inverse condition was found in bed height. The bed depth service time (BDST) Adams–Bohart model was used to analyze the experimental data. The regeneration efficiency was observed 40.1%, 75% and 53% for Cr(VI), Ni(II) and Zn(II) without any significant alteration in sorption capacity after 5th sorption–desorption cycles.
Keywords: Immobilized biosorbent; Packed-bed column; Breakthrough time; Sorption capacity; Bohart–Adams (BDST) model

32.
Photoelectrochemical hydrogen production on Cu2ZnSnS4/Mo-mesh thin-film electrodes prepared by electroplating Original Research Article
Chemical Physics Letters, Volume 501, Issues 4-6, 7 January 2011, Pages 619-622
Guijun Ma, Tsutomu Minegishi, Daisuke Yokoyama, Jun Kubota, Kazunari Domen
Abstract
P-type Cu2ZnSnS4 (CZTS) thin film was deposited on Mo-mesh substrate by sulfurization of electroplated Zn/Sn/Cu/Mo-mesh precursor. A photoelectrochemical water splitting reaction was investigated using a three-electrode reaction system composed of a Pt/CdS/CZTS/Mo-mesh, Pt wire, and Ag/AgCl as the working, counter, and reference electrodes, respectively, in an electrolyte solution containing Na2SO4 and NaOH. Scanning electron microscopy results indicated that the surface morphology of the CZTS could be changed by changing the pH of the Zn electroplating solution. At a pH of 9, an irregular hollow-column-type CZTS was formed, resulting in the highest CZTS electrode photocurrent observed in this study.

33.
DSSC with a novel Pt counter electrodes using pulsed electroplating techniques Original Research Article
Current Applied Physics, Volume 11, Issue 1, Supplement, January 2011, Pages S147-S153
Chun-Chen Yang, Huan Qing Zhang, Yu Rong Zheng
Abstract
The thin Pt electrode on transparent conductive oxide (TCO) substrate, i.e., FTO/glass, for the dye-sensitized solar cell was prepared by a pulsed electrodeposition method. The characteristic properties of the pulse-plated Pt film were prepared and compared with the conventional sputtered Pt film. The composition and surface morphology of the Pt thin film were examined by scanning electron microscope with energy dispersive X-ray spectroscopy (SEM/EDX), atomic force microscope (AFM). The AFM results indicated that the surface roughness of the pulsed plated Pt film is much higher than that of the sputtered Pt film. The catalytic activities of the as-prepared Pt films were examined by cyclic voltammetry (CV). It was found that the catalytic activities of the pulsed plated Pt films were much higher than those of the sputtered Pt film and the DC-plated Pt film. The highest energy conversion efficiency of ca. 6.0% on the DSSC with the pulse-plated Pt electrode was obtained. The result demonstrated that the pulse-plated thin Pt film can be a good candidate for dye-sensitized solar cell (DSSC) application.
Keywords: Thin Pt film; Pulse-plated Pt; Sputtered Pt; Counter electrode; Dye-sensitized solar cell (DSSC); Energy conversion efficiency

34.
Image analysis for maintenance of coating quality in nickel electroplating baths – Real time control Original Research Article
Analytica Chimica Acta, Volume 706, Issue 1, 7 November 2011, Pages 1-7
M. Vidal, J.M. Amigo, R. Bro, F. van den Berg, M. Ostra, C. Ubide
Abstract
The aim of this paper is to show how it is possible to extract analytical information from images acquired with a flatbed scanner and make use of this information for real time control of a nickel plating process. Digital images of plated steel sheets in a nickel bath are used to follow the process under degradation of specific additives. Dedicated software has been developed for making the obtained results accessible to process operators. This includes obtaining the RGB image, to select the red channel data exclusively, to calculate the histogram of the red channel data and to calculate the mean colour value (MCV) and the standard deviation of the red channel data. MCV is then used by the software to determine the concentration of the additives Supreme Plus Brightner (SPB) and SA-1 (for confidentiality reasons, the chemical contents cannot be further detailed) present in the bath (these two additives degrade and their concentration changes during the process). Finally, the software informs the operator when the bath is generating unsuitable quality plating and suggests the amount of SPB and SA-1 to be added in order to recover the original plating quality.
Keywords: Flatbed scanner; Image analysis; Nickel electrodeposition; Additives determination; “Real control” software; Process analysis

35.
Nanofabrication of hard X-ray optics by metal electroplating in a dry etched mechanically stable inorganic template Original Research Article
Microelectronic Engineering, Volume 88, Issue 8, August 2011, Pages 2552-2555
Gianluca Grenci, Alessandro Pozzato, Alessandro Carpentiero, Enrico Sovernigo, Massimo Tormen
Abstract
A nanofabrication process for high resolution X-ray optics and X-ray lithography masks was developed. The process is based on the plasma etching of a sacrificial hard inorganic interlayer (Si, Si3N4, SiOx or HSQ) used for pattern transfer and aspect ratio amplification. The structures are first defined on a top thin metal film by electron beam lithography and lift-off; a thin nickel layer at the bottom of the hard interlayer is used as etch stop. A base plating (Cr/Au) under the nickel serves as seed layer for the electroplating of an X-ray absorber or phase shifting material. The fabrication is completed by the stripping of the hard template by wet or dry etching. Compared to methods based on analogous process schemes, in which the aspect ratio of nanostructures is instead amplified by pattern transfer into a sacrificial polymer interlayer by oxygen plasma, the investigated method is advantageous for the higher mechanical stability of the nanostructured hard templates with respect to the polymer ones, thus enabling the realization of higher aspect ratio features.
Keywords: X-ray optics; X-ray microscopy; X-ray lithography; HSQ; EBL; Dry etching

36.
Nanoparticle–electrode collision processes: The electroplating of bulk cadmium on impacting silver nanoparticles Original Research Article
Chemical Physics Letters, Volume 511, Issues 4-6, 5 August 2011, Pages 183-186
Yi-Ge Zhou, Neil V. Rees, Richard G. Compton
Abstract
We report, for the first time, the bulk deposition (electroplating) of a metal onto nanoparticles during collisions with an inert electrode surface. Experiments show that for silver nanoparticles, multiple layers of Cd atoms can be electroplated onto the AgNPs from aqueous Cd2+ during collisions with a glassy carbon electrode held at a suitably reducing potential, and an average of 19 atomic layers of cadmium are found to be deposited in the few milliseconds that the NP is in contact with the electrode. For comparison, results are also presented for the underpotential deposition of Cd onto AgNPs under similar conditions.

37.
Effect of copper pretreatment on the zincate process and subsequent electroplating of a protective copper/nickel deposit on the AZ91D magnesium alloy Original Research Article
Electrochimica Acta, Volume 56, Issue 24, 1 October 2011, Pages 8776-8782
Jinwei Tang, Kazuhisa Azumi
Abstract
To obtain a durable Ni coating with excellent adhesion strength on an AZ91D Mg alloy, a pretreatment was performed with a small amount of Cu2+ ions added to the activation bath used in the pretreatment prior to the plating process. In the pretreatment activation process, a high density Cu layer was deposited on both the α-phase and β-phase areas of the substrate accompanied with Mg dissolution. The Cu deposit acted as nucleation seeds for the Zn deposition in the following zincate process which provided a uniform and dense Zn layer almost completely covering the substrate. Then a thin Cu layer was electroplated on this zincated substrate as an undercoating for the succeeding electroplating with Ni. Cross-sectional scanning electron microscopy observations showed that the Cu deposited by the pretreatment enabled the deposition of a protective Ni layer with few defects. This structure also contributed to the improvement of adhesion strength and corrosion resistance as compared with the non-Cu added sample.
Keywords: AZ91D Mg alloy; Cu pretreatment; Nickel electrodeposition; Corrosion protection; Adhesion strength

38.
Assessment of heavy metal tolerance in native plant species from soils contaminated with electroplating effluent Original Research Article
Ecotoxicology and Environmental Safety, In Press, Corrected Proof, Available online 5 August 2011
Poonam Ahlawat Sainger, Rajesh Dhankhar, Manish Sainger, Anubha Kaushik, Rana Pratap Singh
Abstract
Heavy metals concentrations of (Cr, Zn, Fe, Cu and Ni) were determined in plants and soils contaminated with electroplating industrial effluent. The ranges of total soil Cr, Zn, Fe, Cu and Ni concentrations were found to be 1443–3240, 1376–3112, 683–2228, 263–374 and 234–335 mg kg−1, respectively. Metal accumulation, along with hyperaccumulative characteristics of the screened plants was investigated. Present study highlighted that metal accumulation in different plants varied with species, tissues and metals. Only one plant (Amaranthus viridis) accumulated Fe concentrations over 1000 mg kg−1. On the basis of TF, eight plant species for Zn and Fe, three plant species for Cu and two plant species for Ni, could be used in phytoextraction technology. Although BAF of all plant species was lesser than one, these species exhibited high metal adaptability and could be considered as potential hyperaccumulators. Phytoremediation potential of these plants can be used to remediate metal contaminated soils, though further investigation is still needed.
Keywords: Industrial effluent; Heavy metals; India; Phytoremediation; Hyperaccumulators

39.
Recovery of copper and water from copper-electroplating wastewater by the combination process of electrolysis and electrodialysis Original Research Article
Journal of Hazardous Materials, Volume 189, Issue 3, 30 May 2011, Pages 814-820
Changsheng Peng, Yanyan Liu, Jingjing Bi, Huizhen Xu, Abou-Shady Ahmed
Abstract
In this paper, a laboratory-scale process which combined electrolysis (EL) and electrodialysis (ED) was developed to treat copper-containing wastewater. The feasibility of such process for copper recovery as well as water reuse was determined. Effects of three operating parameters, voltage, initial Cu2+ concentration and water flux on the recovery of copper and water were investigated and optimized. The results showed that about 82% of copper could be recovered from high concentration wastewater (HCW, >400 mg/L) by EL, at the optimal conditions of voltage 2.5 V/cm and water flux 4 L/h; while 50% of diluted water could be recycled from low concentration wastewater (LCW, <200 100="" 40="" 4="" 97.9="" 99.5="" according="" almost="" analysis="" and="" as="" at="" be="" because="" before="" both="" br="" by="" combination="" concentrated="" conditions="" consumption="" copper="" could="" developed="" discharged.="" ed="" edx="" effectively="" effluent="" el="" energy="" flux="" for="" from="" further="" h.="" h="" hcw="" high="" however="" kg="" kw="" l="" lcw.="" lcw="" limitation="" m3.="" mg="" not="" of="" optimal="" process="" purity="" realize="" recovered="" recovery="" results="" sem="" should="" showed="" simultaneously="" that="" the="" therefore="" to="" treated="" v="" voltage="" was="" water="" with="">Keywords: Electrolysis; Electrodialysis; Copper recovery; Water reuse; Combination process

40.
Removal of chromium in electroplating wastewater by nanoscale zero-valent metal with synergistic effect of reduction and immobilization Original Research Article
Desalination, Volume 280, Issues 1-3, 3 October 2011, Pages 224-231
Zhanqiang Fang, Xiuqi Qiu, Ruixiong Huang, Xinhong Qiu, Mingyu Li
Abstract
Reductive immobilization of chromium in wastewater by nanoscale zero-valent metal (nZVM) prepared from steel pickling waste liquor was investigated. A series of characterization techniques were conducted to characterize the properties of the synthesized nanoparticles. Effects of pH, buffer substances, natural organic matter (NOM) and hardness were evaluated to probe the impact of environmental factors. Removal of Cr(VI) benefited from a decrease in pH value and the presences of buffer substances and Ca2+. NOM was found to be suppressive on the activity of ZVM, and coupled effect of Ca2+ and NOM was additive effect due to their non-interference when operating under acidic condition. The nZVM was proved to be more effective (up to 40.6-fold) than zero-valent iron and nanoscale zero-valent iron for Cr(VI) removal, and its removal capacity in wastewater was 182 ± 2 mg g−1. The removal mechanism included mass transfer on solid–liquid interface, reduction of Cr(VI) and simultaneous co-precipitation as Cr–Fe (oxy)hydroxide on the surface of nanoparticles. The results presented herein indicated nZVM was promising for in-situ remediation of Cr(VI).

41.
Flatbed scanners as a source of imaging. Brightness assessment and additives determination in a nickel electroplating bath Original Research Article
Analytica Chimica Acta, Volume 694, Issues 1-2, 23 May 2011, Pages 38-45
M. Vidal, J.M. Amigo, R. Bro, M. Ostra, C. Ubide, J. Zuriarrain
Abstract
Desktop flatbed scanners are very well-known devices that can provide digitized information of flat surfaces. They are practically present in most laboratories as a part of the computer support. Several quality levels can be found in the market, but all of them can be considered as tools with a high performance and low cost. The present paper shows how the information obtained with a scanner, from a flat surface, can be used with fine results for exploratory and quantitative purposes through image analysis. It provides cheap analytical measurements for assessment of quality parameters of coated metallic surfaces and monitoring of electrochemical coating bath lives. The samples used were steel sheets nickel-plated in an electrodeposition bath. The quality of the final deposit depends on the bath conditions and, especially, on the concentration of the additives in the bath. Some additives become degraded with the bath life and so is the quality of the plate finish. Analysis of the scanner images can be used to follow the evolution of the metal deposit and the concentration of additives in the bath. Principal component analysis (PCA) is applied to find significant differences in the coating of sheets, to find directions of maximum variability and to identify odd samples. The results found are favorably compared with those obtained by means of specular reflectance (SR), which is here used as a reference technique. Also the concentration of additives SPB and SA-1 along a nickel bath life can be followed using image data handled with algorithms such as partial least squares (PLS) regression and support vector regression (SVR). The quantitative results obtained with these and other algorithms are compared. All this opens new qualitative and quantitative possibilities to flatbed scanners.
Keywords: Image analysis; Flatbed scanner; Principal component analysis; Partial least squares regression; Support vector regression; Nickel electrodeposition; Coating quality

42.
Void-free micro-pattern of nickel fabricated by electroplating with supercritical carbon dioxide emulsion Original Research Article
Microelectronic Engineering, Volume 88, Issue 8, August 2011, Pages 2225-2228
Tso-Fu Mark Chang, Toshikazu Tasaki, Chiemi Ishiyama, Masato Sone
Abstract
Void-free micro-pattern of nickel was fabricated electrochemically by applying supercritical carbon dioxide emulsion (Sc-CO2-E). Evolution of hydrogen gas bubbles is usually the cause of defect and pinholes for microstructures fabricated electrochemically using aqueous electrolyte. Defect and pinholes formed dramatically limit application of the micro-sized metallic pattern in fine and complex mechanical systems. Micro-pattern of nickel pillars with diameters from ca. 50 to 125 μm was fabricated by using film-type SU-8 as the template and brightener-contained Watts bath as the electrolyte. Height of the nickel pillars is limited by thickness of SU-8 film and controlled by current applied and deposition time. Defect was found for micro-pattern of nickel prepared by conventional method; that is without application of Sc-CO2-E. Void-free micro-pattern of nickel was obtained when Sc-CO2-E was applied with experimental pressure and temperature at 15 MPa and 323 K, respectively. In addition, the SU-8 film could be simply peeled off using tweezers when electroplated with Sc-CO2-E using 15-μm-thick SU-8 film.
Keywords: Supercritical carbon dioxide emulsion; Void-free; Micro-pattern; Microstructure; Nickel

43.
Influence of zincate pretreatment on adhesion strength of a copper electroplating layer on AZ91 D magnesium alloy Original Research Article
Surface and Coatings Technology, Volume 205, Issues 8-9, 25 January 2011, Pages 3050-3057
Jinwei Tang, Kazuhisa Azumi
Abstract
Cu was electrodeposited on AZ91 D Mg alloy with zincate pretreatment in an alkaline plating bath, and the effect of zincate pretreatment on adhesion strength of the Cu layer was investigated. Scanning electron microscopy results showed that Zn was mainly deposited on the α-phase surface, and ultrasonic agitation at the initial stage of the zincate pretreatment improved the coverage of the Zn layer even on the β-phase surface, resulting in enhancement of the adhesion strength of the Zn layer and the successive Cu layer to the substrate. Adhesion tests revealed that the plating layer peeled off at the mixed layer of Zn and Cu deposits formed at the interface between the zincated layer and the electrodeposited Cu layer. A smooth Cu surface was obtained in the plating bath containing H3BO3.
Keywords: AZ91 D Mg alloy; Zincate pretreatment; Copper electrodeposition; Adhesion strength

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1.
Effect of Recombinant Plasmid pEGFP-AFP-hTNF on Liver Cancer Cells (HepG2 Cells) in vitro when Delivered by PEG-PEI/Fe3O4 Nanomagnetic Fluid Original Research Article
Journal of the Formosan Medical Association, Volume 110, Issue 5, May 2011, Pages 326-335
Baoxiong Zhuang, Yangde Zhang, Jian Peng, Haowei Zhang, Tiehui Hu, Jie Zeng, Yifan Li

2.
Simultaneous determination of nine flavonoids in Polygonum hydropiper L. samples using nanomagnetic powder three-phase hollow fibre-based liquid-phase microextraction combined with ultrahigh performance liquid chromatography–mass spectrometry Original Research Article
Journal of Pharmaceutical and Biomedical Analysis, Volume 54, Issue 2, 25 January 2011, Pages 311-316
Xian Yang, Bo-Chu Wang, Xue Zhang, Shui-Ping Yang, Wei Li, Qian Tang, Gurinder K. Singh
Abstract
A simple, inexpensive, and efficient nanomagnetic powder three-phase hollow fibre-based liquid-phase microextraction (HF-LPME) technique combined with ultrahigh performance liquid chromatography–mass spectrometry (UPLC–MS) was developed for the simultaneous analysis of nine flavonoids in Polygonum hydropiper L. samples. The final, optimised extraction conditions were as follows: an organic solvent of ethyl acetate, a donor phase of aqueous KH2PO4 at pH 3.0, an acceptor phase of aqueous NaHCO3 at pH 8.5, a stirring rate of 1000 rpm, and an extraction time of 50 min. Under these conditions, analyte calibration curves were all linear, with correlation coefficients ≥0.9994. The relative standard deviation for all analytes in intra-day (0.8–2.2%) and inter-day (1.7–3.5%) precision tests was well within the acceptable ranges, as were the limits of quantitation (LOQ < 0.054 μg/L) and detection (LOD < 0.170 μg/L). Recoveries for all standard compounds were between 95.17% and 99.82%, with a RSD of no more than 2.3%. Correlative analyses demonstrated that the physicochemical parameters of the compounds themselves also influenced the extraction efficiency. This technology proved to be rapid, sensitive, and reliable for the quality control of P. hydropiper L. samples.
Keywords: Polygonum hydropiper L.; Nanomagnetic powder; Three-phase HF-LPME; UPLC–MS

3.
UV laser photodeposition of nanomagnetic soot from gaseous benzene and acetonitrile–benzene mixture Original Research Article
Journal of Photochemistry and Photobiology A: Chemistry, Volume 220, Issues 2-3, 20 May 2011, Pages 188-194
Josef Pola, Akihiko Ouchi, M. Maryško, V. Vorlíček, Jan Šubrt, S. Bakardjieva, Zdeněk Bastl
Abstract
Megawatt KrF laser gas-phase photolysis of benzene and acetonitrile–benzene mixture was studied by using mass spectroscopy–gas-chromatography and Fourier transform infrared spectroscopy for analyses of volatile products, and by Fourier transform infrared, Raman and X-ray photoelectron spectroscopy, electron microscopy and magnetization measurements for analyses of solid products deposited from the gas-phase. The results are consistent with carbonization of benzene and decomposition of non-absorbing acetonitrile in carbonizing benzene through collisions with excited benzene and/or its fragments. The solid products from benzene and acetonitrile–benzene mixture have large surface area and are characterized as nanomagnetic amorphous carbonaceous soot containing unsaturated C centers prone to oxidation. The nanosoot from acetonitrile–benzene mixture incorporates CN groups, confirms reactions of benzene fragments with CN radical and has a potential for modification by reactions at the CN bonds.
Keywords: Benzene; Acetonitrile; Laser photodeposition; Nanomagnetic soot; CN-substituted soot

4.
Adsorption, desorption, and conformational changes of lysozyme from thermosensitive nanomagnetic particles Original Research Article
Journal of Colloid and Interface Science, Volume 320, Issue 1, 1 April 2008, Pages 15-21
N. Shamim, H. Liang, K. Hidajat, M.S. Uddin
Abstract
Adsorption of globular protein, lysozyme, on thermosensitive poly(N-isopropylacrylamide) coated nanomagnetic particles was studied at different temperatures and pHs. It was observed that a maximum amount of lysozyme was adsorbed at a temperature above the lower critical solution temperature (LCST) (32 °C ) of the polymer and at the isoelectric point (pI=11) of lysozyme. Desorption was carried out using either NaH2PO4 (pH 4) or NaSCN (pH 6) as the desorbing agents. Conformational changes in lysozyme on desorption from nanomagnetic particles was studied by circular dichroism and intrinsic fluorescence spectroscopy. Lysozyme desorbed by NaH2PO4 showed very little conformational changes while lysozyme desorbed by NaSCN showed significant conformational changes, and 87% enzymatic activity was retained in the desorbed enzyme for desorption by NaH2PO4.
Keywords: N-isopropylacrylamide; Lower critical solution temperature (LCST); Isoelectric point; Lysozyme; Conformational changes

5.
Thermosensitive polymer (N-isopropylacrylamide) coated nanomagnetic particles: Preparation and characterization Original Research Article
Colloids and Surfaces B: Biointerfaces, Volume 55, Issue 1, 15 March 2007, Pages 51-58
N. Shamim, L. Hong, K. Hidajat, M.S. Uddin
Abstract
Thermosensitive polymer coated nanomagnetic adsorbents were synthesized by seed polymerization using surface modified nanomagnetic particles as the seeds. The Fe3O4 nanomagnetic particles were prepared by chemical precipitation of Fe2+ and Fe3+ salts in the ratio of 1:2 under alkaline and inert condition. The surface of these particles was modified by surfactants to achieve stability against agglomeration. These stable particles were then polymerized using N-isopropylacrylamide (NIPAM) as the main monomer, methylene-bis-acrylamide as the crosslinker and potassium per sulfate as the initiator. The thermosensitive adsorbents were characterized by using transmission electron micrography (TEM) and vibrating sample magnetometer (VSM). TEM showed that the particle remained discrete with a mean diameter of 12 nm. Magnetic measurements revealed that the particles are superparamagnetic only with a decrease of magnetism after binding with the polymer due to the increase in surface spin disorientation. Pure Fe3O4 spinel structure of these nanoparticles was indicated by the X-ray diffraction (XRD) patterns. The polymerization of NIPAM with the surface modified nanomagnetic particles was confirmed by Fourier transform spectroscopy (FTIR), Thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). In addition, the adsorption/desorption of BSA molecule on these thermosensitive nanoparticles was investigated as a function of temperature. More than 60% desorption efficiency was achieved under appropriate condition.
Keywords: Surfactant; Thermosensitive magnetic nanoparticles; N-Isopropylacrylamide; Superparamagnetism

6.
On-chip Extraordinary Hall-effect sensors for characterization of nanomagnetic logic devices Original Research Article
Solid-State Electronics, Volume 54, Issue 9, September 2010, Pages 1027-1032
M. Becherer, J. Kiermaier, S. Breitkreutz, G. Csaba, X. Ju, J. Rezgani, T. Kießling, C. Yilmaz, P. Osswald, P. Lugli, D. Schmitt-Landsiedel
Abstract
Ferromagnetic Co/Pt films and single-domain magnets are characterized by various types of Extraordinary Hall-Effect (EHE) sensors. The magnetron sputtered multilayer films are annealed and measured in the temperature range of 22 °C T 75 °C. By focused ion beam (FIB) irradiation, the magnetic properties of the Co/Pt stack are tailored to define both the switching field and the geometry of nanomagnetic single domain dots. A submicron sized EHE-sensor for read-out of field-coupled computing devices is presented. The applied sensing structure is suitable to electrically probe the output states of field-coupled magnetic logic gates. Furthermore, it reveals details on the magnetic properties of submicron-scale single-domain dots and the main measured features are confirmed by micromagnetic simulations. A ‘split-current’ architecture is chosen, where Hall sensing takes place in a single lateral direction, in order to keep field-coupling to adjacent nanomagnets undisturbed. From angular measurements we conclude that the reversal mechanism of the FIB patterned magnetic dots is domain-wall driven. The sensor is a main component needed for integration of nanomagnetic computing units embedded into microelectronic systems.
Keywords: Extraordinary Hall-Effect; Co/Pt multilayer; Magnetic QCA; Field-coupled logic; Ferromagnetic computing

7.
Vibration sample magnetometry, a good tool for the study of nanomagnetic inclusions Original Research Article
Superlattices and Microstructures, Volume 43, Issues 5-6, May-June 2008, Pages 482-486
S. Diaz-Castanon, J.C. Faloh-Gandarilla, E. Munoz-Sandoval, M. Terrones
Abstract
The accurate determination of the ferromagnetic contribution in a composite in which the ratio of the ferromagnetic part vs. the total of composite is 10−4–10−5 is a problem of great importance in relation to the development of new materials in our days. In this work, the potential of Vibration Sample Magnetometry (VSM) in the identification and quantification of nanomagnetic inclusions is illustrated and discussed in three different cases: PbFe12O19/ Al2O3 thin films, nanopowders of magnetite in a polymeric matrix, and carbon nanotubes with iron inside in a silica matrix (Fe/ CNx/ SiO2). In all cases, the determination of the existence of preferential orientation, the correct quantification of the magnetic part, and the dependence of the coercive field with on synthesis conditions were revealed using this technique.
Keywords: Magnetic characterization; Nanostructures

8.
Adaptation and performance of the Cartesian coordinates fast multipole method for nanomagnetic simulations Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 22, November 2009, Pages 3687-3692
Wen Zhang, Stephan Haas
Abstract
An implementation of the fast multiple method (FMM) is performed for magnetic systems with long-ranged dipolar interactions. Expansion in spherical harmonics of the original FMM is replaced by expansion of polynomials in Cartesian coordinates, which is considerably simpler. Under open boundary conditions, an expression for multipole moments of point dipoles in a cell is derived. These make the program appropriate for nanomagnetic simulations, including magnetic nanoparticles and ferrofluids. The performance is optimized in terms of cell size and parameter set (expansion order and opening angle) and the trade off between computing time and accuracy is quantitatively studied. A rule of thumb is proposed to decide the appropriate average number of dipoles in the smallest cells, and an optimal choice of parameter set is suggested. Finally, the superiority of Cartesian coordinate FMM is demonstrated by comparison to spherical harmonics FMM and FFT.
Keywords: FMM; Cartesian; Magnet

9.
Thermosensitive polymer coated nanomagnetic particles for separation of bio-molecules Original Research Article
Separation and Purification Technology, Volume 53, Issue 2, 25 February 2007, Pages 164-170
N. Shamim, L. Hong, K. Hidajat, M.S. Uddin
Abstract
Core–shell type thermosensitive magnetic particles were prepared via seed polymerization process. Double layer surfactant coated magnetic particles were first synthesized and then a rich poly-(N-isopropylacrylamide) (PNIPAM) shell layer was attached using double layer magnetic particles as the seeds. Thiodiglycolic acid was used as the primary surfactant and 4-vinylaniline as the secondary surfactant. Carboxylated thermosensitive microspheres were prepared by adding methacrylic acid (MAA) in the polymerization process. PNIPAM has a lower critical solution temperature (LCST) of 32 °C in water, and changes from hydrophilic below the LCST to hydrophobic above it. The size of these thermosensitive polymer coated magnetic particles was measured by using transmission electron microscopy (TEM). TEM results show that magnetic particles were nanosized and the calculated mean diameter of the particles was about 12 nm. Bovine serum albumin (BSA) was selected as a model protein for the separation study. Adsorption of BSA on the thermosensitive magnetic particles was mainly dependent on the properties of the particles’ surface. By increasing the temperature above the LCST of PNIPAM, the particles shrank and were able to adsorb larger quantity of proteins, which was subsequently desorbed at lower temperature. It was believed that carboxylated thermosensitive particles adsorb proteins through hydrogen bonding. When the two extremes of hydrophobic interaction and hydrogen bonding were compared, it was found that more proteins are adsorbed using the later interaction.
Keywords: Double layer magnetic particles; Thermosensitive magnetic particles; Poly-(N-isopropylacrylamide); Lower critical solution temperature (LCST); Methacrylic acid (MAA); Bovine serum albumin (BSA); Adsorption

10.
Extracting anisotropy energy barrier distributions of nanomagnetic systems from magnetization/susceptibility measurements
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 9, May 2009, Pages L21-L27
Rongkun Zheng, Hongwei Gu, Bei Zhang, Hui Liu, Xixiang Zhang, Simon P. Ringer
Abstract
Anisotropy barrier distributions of single domain particle systems are an important issue in the nanomagnetism and its applications. Different methods to extract the distribution from temperature, field, or time-dependent magnetization/susceptibility are reviewed and compared. A single domain particle system is measured to test the methods.
Keywords: Magnetic nanoparticles; Nanomagnetism; Anisotropy barrier distribution; Single domain particles

11.
United States Patent 7,126,797
Hasegawa , et al. October 24, 2006
________________________________________
Spin valve magnetoresistive element having pinned magnetic layer composed of epitaxial laminated film having magnetic sublayers and nanomagnetic interlayer
Abstract
A magnetic sensor includes a pinned magnetic layer having first and second magnetic sublayers sandwiching a nonmagnetic metal layer. The nonmagnetic metal layer contains at least one of Ru, Re, Os, Ti, Rh, Ir, Pd, Pt, and Al. The atoms in the first magnetic sublayer and the atoms in the nonmagnetic metal layer overlap with each other, while each of the crystal structures is deformed. The deformations in the crystal structure of the first magnetic sublayer increase the magnetostriction constant, thereby increasing the magnetoelastic effect of the magnetic sensor.

12.
United States Patent 6,906,256
Wang June 14, 2005
________________________________________
Nanomagnetic shielding assembly
Abstract
An assembly that contains a substrate, nanomagnetic material, and a device for cooling the substrate. The nanomagnetic material has a mass density of at least about 0.01 grams per cubic centimeter, a saturation magnetization of from about 1 to about 36,000 Gauss, a coercive force of from about 0.01 to about 5,000 Oersteds, a relative magnetic permeability of from about 1 to about 500,000, and an average particle size of less than about 100 nanometers.

13.
United States Patent 6,828,786
Scherer , et al. December 7, 2004
______________________________________
Method and apparatus for nanomagnetic manipulation and sensing
Abstract
The invention combines (A) capabilities in fabrication, characterization, and manipulation of single domain magnetic nanostructures, with (B) the use of binding chemistry of biological molecules to modify the magnetic nanostructures into magnetic sensors and magnetically controllable nanoprobes. A biological characterization scheme is realized by combining nanomanipulation and observation of small magnetic structures in fluids. By coating nanomagnets with biological molecules, ultra-small, highly sensitive and robust biomagnetic devices are defined, and molecular electronics and spin electronics are combined. When these nano-sensors are integrated into microfluidic channels, highly efficient single-molecule detection chips for rapid diagnosis and analysis of biological agents are constructed.

14.
United States Patent 6,815,609
Wang , et al. November 9, 2004
________________________________________
Nanomagnetic composition
Abstract
A magnetically shielded substrate assembly includes a substrate and, disposed over the substrate, a magnetic shield with a magnetic shielding factor of at least about 0.5. The magnetic shield has a film of nanomagnetic material containing at least about 40 weight percent of nomagnetic material with a mass density of at least about 0.01 grams per cubic centimeter, a saturization magnetization of from about 1 to about 36,000 Gauss, a coercive force of from about 0.01 to about 5,000 Oersteds, a relative magnetic permeability of from about 1 to about 500,000, and an average particle size of less than about 100 nanometers. This film of nanomagnetic material has a squareness of from about 0.5 to about 1.0.

Magnetic Materials

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1.
Modeling of two-phase magnetic materials based on Jiles–Atherton theory of hysteresis Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 324, Issue 1, January 2012, Pages 20-22
A. Raghunathan, Y. Melikhov, J.E. Snyder, D.C. Jiles
Abstract
The Jiles–Atherton (JA) theory of hysteresis has been extended in the present paper to model hysteresis in two-phase magnetic materials. Two-phase materials are those that exhibit two magnetic phases in one hysteresis cycle: one at lower fields and the other at higher fields. In magnetic hysteresis, the transition from one phase to the other i.e. low field phase to high field phase depends mainly on the exchange field. Hence, the material-dependent microstructural parameters of JA theory: spontaneous magnetization, MS, pinning factor, k, domain density, a, domain coupling, α, and reversibility factor, c, are represented as functions of the exchange field. Several cases based on this model have been discussed and compared with the measured data from existing literature. The shapes of the calculated and measured hysteresis loops are in excellent agreement.
Keywords: Magnetic hysteresis; Magnetization; Two-phase material; Jiles–Atherton theory

2.
A new ferromagnetic hysteresis model for soft magnetic composite materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 323, Issue 1, January 2011, Pages 67-71
Bogomir Zidarič, Damijan Miljavec
Abstract
A new ferromagnetic hysteresis model for soft magnetic composite materials based on their specific properties is presented. The model relies on definition of new anhysteretic magnetization based on the Cauchy–Lorentz distribution describing the maximum energy state of magnetic moments in material. Specific properties of soft magnetic composite materials (SMC) such as the presence of the bonding material, different sizes and shapes of the Fe particles, level of homogeneity of the Fe particles at the end of the SMC product treatment, and achieved overall material density during compression, are incorporated in both the anhysteretic differential magnetization susceptibility and the irreversible differential magnetization susceptibility. Together they form the total differential magnetization susceptibility that defines the new ferromagnetic hysteresis model. Genetic algorithms are used to determine the optimal values of the proposed model parameters. The simulated results show good agreement with the measured results.
Keywords: Composite materials; Hysteresis model; Powder metallurgy; Magnetization; Magnetic measurements

3.
Restricted access magnetic materials prepared by dual surface modification for selective extraction of therapeutic drugs from biological fluids Original Research Article
Journal of Magnetism and Magnetic Materials, In Press, Corrected Proof, Available online 23 August
2011
Yu Wang, Yuxia Wang, Lei Chen, Qian-Hong Wan
Abstract
Magnetic porous particles with dual functionality have been prepared by a two-step procedure and evaluated as novel restricted access materials for extraction of therapeutic agents from biological fluids. The magnetic silica particles served as scaffolds were first modified with diol groups, which were then converted to octadecyl esters through reaction with stearoyl chloride. In the second step, the octadecyl esters on the exterior surface were hydrolyzed by the action of lipase to yield magnetic particles with hydrophobic reversed-phase ligands on the inner surface and biocompatible diol groups on the outer surface. The restricted access behavior of the resulting materials was confirmed by differential binding of small molecules such as methotrexate (MTX), leucovorin (LV) and folic acid (FA) relative to bovine serum albumin. While MTX, LV and FA were all bound to the magnetic particles with high affinity, the adsorption of the protein was markedly reduced due to size exclusion effect. The utility of the magnetic particles for sample preparation was tested in solid-phase extraction of MTX, LV and FA from spiked human serum and the effects of the SPE conditions on the recovery of the analytes were systematically studied. Moreover, the magnetic particle-based sample preparation procedure coupled with reversed-phase liquid chromatography analysis was validated in terms of specificity, linearity and reproducibility. The method was shown to be free from interference of endogenous compounds and linear over the concentration range of 0.5–10 μg/mL for the three drugs studied. The limits of detection for the three drugs in serum were in the range of 0.160−0.302 μg/mL. Reproducibility expressed as the RSD of the recovery for ten replicated extractions at three different concentrations was found to be less than 8.93%. With a unique combination of surface functionality with magnetic cores, the restricted access magnetic particles may be adapted in automated and high throughput protocols for routine analysis of a large volume of clinical samples.
Keywords: Magnetic particle; Porous silica; Restricted access material; Solid-phase extraction; Biological fluid; Clinical analysis

4.
Magnetic materials from co-precipitated ferrite nanoparticles Original Research Article
Materials Science and Engineering: B, Volume 167, Issue 2, 15 March 2010, Pages 85-90
V. Musat, O. Potecasu, R. Belea, P. Alexandru
Abstract
Some of recent technological advances in electronics need very compact magnetic materials. The paper presents the morphology and the magnetic properties of very dense polycrystalline magnetic materials obtained from co-precipitated manganese ferrite nanoparticles. The ferrite nanoparticles, with average diameter in the range of 13–25 nm, were obtained through an original low-cost co-precipitation route from aqueous solution of Mn2+ and Fe3+ ions generated by redox reactions between stoichiometric amounts of MnO2 (piroluzite) and FeSO4•7H2O raw materials. Very dense homogeneous polycrystalline magnetic materials with high square hysteresis loop (Br/Bs = 0.91) and low intrinsic coercivity were obtained using the co-precipitated un-doped manganese ferrite nanoparticles.
Keywords: Co-precipitation; Nanoparticle; Manganese ferrite; Compact magnetic material; Magnetic anisotropy

5.
Monte Carlo study of the spin transport in magnetic materials Original Research Article
Computational Materials Science, Volume 49, Issue 4, Supplement 1, October 2010, Pages S204-S209
Y. Magnin, K. Akabli, H.T. Diep, I. Harada
Abstract
The resistivity in magnetic materials has been theoretically shown to depend on the spin–spin correlation function which in turn depends on the magnetic field, the density of conduction electron, the magnetic ordering stability, etc. However, these theories involved a lot of approximations, so their validity remained to be confirmed. The purpose of this work is to show by newly improved extensive Monte Carlo (MC) simulation the resistivity of the spin resistivity from low-T ordered phase to high-T paramagnetic phase in ferromagnetic and antiferromagnetic films. We take into account the interaction between the itinerant spins and the localized lattice spins as well as the interaction between itinerant spins themselves. We show that in ferromagnets the resistivity shows a sharp peak at the magnetic phase transition in agreement with previous theories in spite of their numerous approximations. Resistivity in antiferromagnets on the other hand shows no peak for the SC, BCC and diamond lattices. Discussion on the origin of these resistivity behaviors is given.
Keywords: Spin transport; Monte Carlo simulation; Magnetic resistivity; Magnetic materials

6.
New heat generation material in AC magnetic field for Y3Fe5O12-based powder material synthesized by reverse coprecipitation method
Materials Letters, Volume 65, Issue 10, 31 May 2011, Pages 1454-1456
Hiromichi Aono, Kenji Moritani, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa,
Yuji Watanabe
Abstract
We found the most promising powder material for the application of the thermal coagulation therapy for the treatment of cancerous tissues. The maximum heat generation ability (ΔT = 40–77 °C, 370 kHz, 1.77 kA•m− 1) was obtained for the powder materials by the calcination at 1100 °C for the Y3 − XGdXFe5O12 system. This ΔT value is higher than ca. ΔT = 30 °C in same magnetic field for fine FeFe2O4 particles as the candidate material for this type of therapy. The particle growth with the formation of the cubic single phase might influence to the high heat generation. As an unexpected result, the Gd3Fe5O12 (X = 3) has no heat generation ability in an AC magnetic field.
Keywords: Magnetic materials; Ceramics; Y3Fe5O12; Heat generation ability; AC magnetic field; Coagulation therapy

7.
Magnetic mesoporous materials for removal of environmental wastes Original Research Article
Journal of Hazardous Materials, Volume 192, Issue 3, 15 September 2011, Pages 1140-1147
Byoung Chan Kim, Jinwoo Lee, Wooyong Um, Jaeyun Kim, Jin Joo, Jin Hyung Lee, Ja Hun
Kwak, Jae Hyun Kim, Changha Lee, Hongshin Lee, R. Shane Addleman, Taeghwan Hyeon,
Man Bock Gu, Jungbae Kim
Abstract
We have synthesized two different magnetic mesoporous materials that can be easily separated from aqueous solutions by applying a magnetic field. Synthesized magnetic mesoporous materials, Mag-SBA-15 (magnetic ordered mesoporous silica) and Mag-OMC (magnetic ordered mesoporous carbon), have a high loading capacity of contaminants due to high surface area of the supports and high magnetic activity due to the embedded iron oxide particles. Application of surface-modified Mag-SBA-15 was investigated for the collection of mercury from water. The mercury adsorption using Mag-SBA-15 was rapid during the initial contact time and reached a steady-state condition, with an uptake of approximately 97% after 7 h. Application of Mag-OMC for collection of organics from water, using fluorescein as an easily trackable model analyte, was explored. The fluorescein was absorbed into Mag-OMC within minutes and the fluorescent intensity of solution was completely disappeared after an hour. In another application, Mag-SBA-15 was used as a host of tyrosinase, and employed as recyclable catalytic scaffolds for tyrosinase-catalyzed biodegradation of catechol. Crosslinked tyrosinase in Mag-SBA-15, prepared in a two step process of tyrosinase adsorption and crosslinking, was stable enough for catechol degradation with no serious loss of enzyme activity. Considering these results of cleaning up water from toxic inorganic and organic contaminants, magnetic mesoporous materials have a great potential to be employed for the removal of environmental contaminants and potentially for the application in large-scale wastewater treatment plants.
Keywords: Magnetic mesoporous materials; Adsorption; Mercury; Tyrosinase; Catehcol degradation

8.
The improved technique of electric and magnetic parameters measurements of powdered materials Original Research Article
Advances in Engineering Software, Volume 42, Issue 11, November 2011, Pages 911-916
Roman Kubacki, Leszek Nowosielski, Rafał Przesmycki
Abstract
This paper presents the measurement technique that allows to determine the relative permittivity and permeability of powdered materials. Measurements are realized in a coaxial transmission line which guarantees the broad band frequency characterization. Calculations utilize the scattering matrix parameters of the two-port formed by the sample of powdered material supported by two dielectric walls. The proposed measurement procedure is demonstrated in the example of ferrite powder – Yiitrium Garnet YIG class ferrite for which the relative permittivity (ε′,ε″) and permeability (μ′,μ″) are determined in the frequency range of 200–1200 MHz.
Keywords: Microwave measurements; Permittivity and permeability measurements; Scattering parameters; Absorbing materials; Magnetic materials; Powdered ferrite measurements

9.
Magnetic dependence of cyclotron transition absorption in piezoelectric materials based on the quantum transport theory Original Research Article
Thin Solid Films, Volume 519, Issue 23, 30 September 2011, Pages 8414-8418
S.H. Lee, J.T. Lee, J.Y. Sug, J.H. Lee, G. Sa-Gong
Abstract
We investigated theoretically the magnetic field dependence of the quantum optical transition of quasi 2-Dimensional Landau splitting system, in CdS and ZnO. Through the analysis of the current work, we found the increasing properties of the optical Quantum Transition Line Shapes (QTLSs) which show the absorption power and the Quantum Transition Line Widths(QTLWs) with the magnetic-field in CdS and ZnO. We also found that QTLW, γ(B)total of CdS < γ(B)total of ZnO in the magnetic field region B < 25 Tesla.
Keywords: CdS and ZnO; Quantum transport theory; Equilibrium Average Projection Scheme (EAPS); Response formula and scattering factor formula; Electron phonon coupling system; Quantum Transition Line Shapes (QTLS); Quantum Transition Line Widths (QTLW); Cyclotron resonance

10.
Magnetic properties of (ZnxFe1 − x)A(Mn1 − xFe1 + x)BO4 materials Original Research Article
Chemical Physics Letters, Volume 513, Issues 4-6, 15 September 2011, Pages 280-284
R. Masrour, M. Hamedoun, A. Benyoussef
Abstract
The magnetic properties of mixed spinels ferrite are studied. The effect of Zn doping on magnetic properties of MnFe2O4 ferrite spinel has been studied. The exchange interactions (JAA, JAB and JBB) and exchange constants (λAA, λAB and λBB) of this material are obtained. The general expression of saturation magnetization, the critical temperature and Curie constant (C) are obtained by the mean field theory. The high temperature series expansion combined with the Padé approximant is given to determinate the critical temperature of the mixed spinels. The critical exponent associated with the magnetic susceptibility is given for different values of Padé.

11.
Novel Cu (II) magnetic ion imprinted materials prepared by surface imprinted technique combined with a sol–gel process Original Research Article
Journal of Hazardous Materials, Volume 192, Issue 3, 15 September 2011, Pages 949-955
Xubiao Luo, Shenglian Luo, Youcai Zhan, Hongying Shu, Yining Huang, Xinman Tu
Abstract
A novel Cu (II) magnetic ion-imprinted polymer (MIIP) was synthesized by surface imprinting technique combined with a sol–gel process. The adsorbent of Cu (II)-MIIP shows higher capacity and selectivity than that of magnetic non-imprinted polymers (MNIP). Adsorption capacities of Cu (II)-MIIP and MNIP are 24.2 and 5.2 mg/g for Cu (II) ions, respectively. The selectivity coefficients of the Cu (II)-MIIP for Cu (II)/Zn (II) and Cu (II)/Ni (II) are 91.84 and 133.92, respectively. Kinetics studies show that the adsorption process obeys pseudo-second-order rate mechanism with an initial adsorption rate of 132.48 for Cu (II)-MIIP and 2.41 mg g−1 min−1 for MNIP. In addition, no obvious decrease was observed after up to five adsorption cycles, indicating that the Cu (II)-MIIP is of high stability.

12.
Magnetic mesoporous materials for removal of environmental wastes Original Research Article
Journal of Hazardous Materials, Volume 192, Issue 3, 15 September 2011, Pages 1140-1147
Byoung Chan Kim, Jinwoo Lee, Wooyong Um, Jaeyun Kim, Jin Joo, Jin Hyung Lee, Ja Hun
Kwak, Jae Hyun Kim, Changha Lee, Hongshin Lee, R. Shane Addleman, Taeghwan Hyeon,
Man Bock Gu, Jungbae Kim
Abstract
We have synthesized two different magnetic mesoporous materials that can be easily separated from aqueous solutions by applying a magnetic field. Synthesized magnetic mesoporous materials, Mag-SBA-15 (magnetic ordered mesoporous silica) and Mag-OMC (magnetic ordered mesoporous carbon), have a high loading capacity of contaminants due to high surface area of the supports and high magnetic activity due to the embedded iron oxide particles. Application of surface-modified Mag-SBA-15 was investigated for the collection of mercury from water. The mercury adsorption using Mag-SBA-15 was rapid during the initial contact time and reached a steady-state condition, with an uptake of approximately 97% after 7 h. Application of Mag-OMC for collection of organics from water, using fluorescein as an easily trackable model analyte, was explored. The fluorescein was absorbed into Mag-OMC within minutes and the fluorescent intensity of solution was completely disappeared after an hour. In another application, Mag-SBA-15 was used as a host of tyrosinase, and employed as recyclable catalytic scaffolds for tyrosinase-catalyzed biodegradation of catechol. Crosslinked tyrosinase in Mag-SBA-15, prepared in a two step process of tyrosinase adsorption and crosslinking, was stable enough for catechol degradation with no serious loss of enzyme activity. Considering these results of cleaning up water from toxic inorganic and organic contaminants, magnetic mesoporous materials have a great potential to be employed for the removal of environmental contaminants and potentially for the application in large-scale wastewater treatment plants.

13.
Synthesis and magnetic properties of hexagonal Y(Mn,Cu)O3 multiferroic materials Original Research Article
Journal of Magnetism and Magnetic Materials, In Press, Uncorrected Proof, Available online 9 September 2011
L. Jeuvrey, O. Peña, A. Moure, C. Moure
Abstract
Single-phase hexagonal-type solid solutions based on the multiferroic YMnO3 material were synthesized by a modified Pechini process. Copper doping at the B-site (YMn1−xCuxO3; x<0.15) and self-doping at the A-site (Y1+yMnO3; y<0.10) successfully maintained the hexagonal structure. Self-doping was limited to y(Y)=2 at% and confirmed that excess yttrium avoids formation of ferromagnetic manganese oxide impurities but creates vacancies at the Mn site. Chemical substitution at the B-site inhibits the geometrical frustration of the Mn3+ two-dimensional lattice. The magnetic transition at TN decreases from 70 K down to 49 K, when x(Cu) goes from 0 to 15 at%. Weak ferromagnetic Mn3+–Mn4+ interactions created by the substitution of Mn3+ by Cu2+, are visible through the coercive field and spontaneous magnetization but do not modify the overall magnetic frustration. Presence of Mn3+–Mn4+ pairs leads to an increase of the electrical conductivity due to thermally-activated small-polaron hopping mechanisms. Results show that local ferromagnetic interactions can coexist within the frustrated state in the hexagonal polar structure.

14.
Role of external magnetic field during friction of ferromagnetic materials Original Research Article
Wear, Volume 271, Issues 11-12, 2 September 2011, Pages 2991-2997
Jile Jiang, Yu Tian, Yonggang Meng
Abstract
Effect of magnetic field on the friction between two crossed steel cylinders in reciprocating motion in ambient air was experimentally studied in a speed range of 0.012–0.24 m/s and a load range of 0.5–6 N. Upon the applying of an external magnetic field, the friction force and the acoustic emission (AE) signal increased while the wear rate decreased. The increase of friction force is mainly ascribed to the magnetic field induced attractive force between cylinders acting as an extra normal load, which can be substituted by a mechanically exerted equivalent normal load to obtain the similar lateral force and AE signal. While the friction coefficient decreased with the increase of the normal load, the friction coefficient upon applying magnetic field decreased due to a higher equivalent normal load. The relationships among friction coefficient, sliding velocity, normal load and AE signal have been extensively discussed. Analysis of the energy transition from friction to AE signal showed that the external magnetic field could suppress the elastic wave releasing during friction. Also the wear was alleviated by the lubrication of debris concentrated around the contact region in the presence of a magnetic field.

15.
Restricted access magnetic materials prepared by dual surface modification for selective extraction of therapeutic drugs from biological fluids Original Research Article
Journal of Magnetism and Magnetic Materials, In Press, Corrected Proof, Available online 23 August 2011
Yu Wang, Yuxia Wang, Lei Chen, Qian-Hong Wan
Abstract
Magnetic porous particles with dual functionality have been prepared by a two-step procedure and evaluated as novel restricted access materials for extraction of therapeutic agents from biological fluids. The magnetic silica particles served as scaffolds were first modified with diol groups, which were then converted to octadecyl esters through reaction with stearoyl chloride. In the second step, the octadecyl esters on the exterior surface were hydrolyzed by the action of lipase to yield magnetic particles with hydrophobic reversed-phase ligands on the inner surface and biocompatible diol groups on the outer surface. The restricted access behavior of the resulting materials was confirmed by differential binding of small molecules such as methotrexate (MTX), leucovorin (LV) and folic acid (FA) relative to bovine serum albumin. While MTX, LV and FA were all bound to the magnetic particles with high affinity, the adsorption of the protein was markedly reduced due to size exclusion effect. The utility of the magnetic particles for sample preparation was tested in solid-phase extraction of MTX, LV and FA from spiked human serum and the effects of the SPE conditions on the recovery of the analytes were systematically studied. Moreover, the magnetic particle-based sample preparation procedure coupled with reversed-phase liquid chromatography analysis was validated in terms of specificity, linearity and reproducibility. The method was shown to be free from interference of endogenous compounds and linear over the concentration range of 0.5–10 μg/mL for the three drugs studied. The limits of detection for the three drugs in serum were in the range of 0.160−0.302 μg/mL. Reproducibility expressed as the RSD of the recovery for ten replicated extractions at three different concentrations was found to be less than 8.93%. With a unique combination of surface functionality with magnetic cores, the restricted access magnetic particles may be adapted in automated and high throughput protocols for routine analysis of a large volume of clinical samples.

16.
Product change of molecule-magnetic material synthesis induced by magnetic field in hydrothermal system Original Research Article
Journal of Crystal Growth, Volume 329, Issue 1, 15 August 2011, Pages 82-85
Helin Niu, Jitang Chen, Qiong Niu, Yuanhao Gao, Jiming Song, Changjie Mao, Shengyi Zhang, Qianwang Chen
Abstract
4-(imidazol-1-yl) benzoic acid (HL, L=C10H7N2O2), Copper sulfate, and sodium azide were selected as precursors, an interesting case of magnetic field-induced change in the final product of molecule-magnetic materials was observed. Without external magnetic field, the only green single crystal G [Cu5(C10H7N2O2)4 (N3)2(SO4)2]n was prepared, but under 0.2 T external magnetic field, the other blue violet single crystal B [Cu(C10H7N2O2)2]n was found beside the green single crystal G. The product prepared under magnetic field comprises ca 34% B and 66% G. It indicates that the magnetic field induction is a dominating factor to the final product of self-assembly reaction for the metal-organic complex. The experiments have suggested a kind of effective control means to fabricate new molecule-magnetic materials under mild magnetic field induction.

17.
Feature Selection and Neural Network for analysis of microstructural changes in magnetic materials Original Research Article
Expert Systems with Applications, Volume 38, Issue 8, August 2011, Pages 10547-10553
J.A. Pérez-Benitez, L.R. Padovese
Abstract
This work presents a Feature Selection Algorithm for optimization of a Probabilistic Neural Network. The aim of this Probabilistic Neural Network is classifying signals obtained from magnetic material samples where two micro-structural parameters were changed simultaneously. The combination of the Feature Selection Algorithm with the Probabilistic Neural Network shows both, classification rate outcomes and classification speed, higher than those coming from traditional Probabilistic Neural Networks.
Keywords: Envelope; Neural Networks; Nondestructive methods; Probabilistic Neural Networks; Feature selection

18.
Magneto-electro-elastic coated inclusion problem and its application to magnetic-piezoelectric composite materials Original Research Article
International Journal of Solids and Structures, Volume 48, Issues 16-17, August 2011, Pages 2393-2401
F. Dinzart, H. Sabar
Abstract
In this work, a micromechanical model for th
e estimate of the magneto-electro-elastic behavior of the magnetic-piezoelectric composites with coated reinforcements is proposed. The coating is considered as a thin layer with properties different from those of the inclusion and the matrix. The micromechanical approach based on the Green’s functions techniques and on the interfacial operators is designed for solving the magneto-electro-elastic inhomogeneous coated inclusion problem. The effective magneto-electro-elastic properties of the composite containing thinly coated inclusions are obtained through the Mori–Tanaka’s model. Numerical investigations into magneto-electro-elastic moduli responsible for the magneto-electric coupling are presented as functions of the volume fraction and characteristics of the coated inclusions. Comparisons with existing models are presented for various shape and orientation of the coated inclusions.
Keywords: Micro-mechanics; Magnetic-piezoelectric composite materials; Coated inclusion; Mori–Tanaka’s model

19.
Magnetic nanocomposites with drug-intercalated layered double hydroxide shell supported on commercial magnetite and laboratory-made magnesium ferrite core materials Original Research Article
Materials Science and Engineering: C, Volume 31, Issue 5, 20 July 2011, Pages 851-857
Ahmet Nedim Ay, Deniz Konuk, Birgül Zümreoğlu-Karan
Abstract
Mg–Al-layered double hydroxide intercalated with a model drug, salicylate, was deposited on laboratory-made magnesium ferrite and commercial magnetite nanoparticles. The obtained core–shell nanocomposites have been characterized by a variety of methods. The combined information from X-ray diffraction patterns, electron diffraction patterns, FTIR spectra, X-ray photoelectron spectra, electron microscopy images, thermogravimetric analysis and microchemical analysis has indicated a similar nature and composition for the two samples. Magnetic measurements have revealed that although the inherent magnetization of magnetite was significantly higher, the nanocomposites displayed nearly similar magnetic properties.
Keywords: Nanocomposites; Core–shell structures; Organic–inorganic hybrids; Layered double hydroxides; Intercalations

20.
Preparation and evaluation of magnetic carbonaceous materials for pesticide and metal removal Original Research Article
Journal of Colloid and Interface Science, Volume 359, Issue 2, 15 July 2011, Pages 407-412
Masaki Ohno, Hiroki Hayashi, Kazuyuki Suzuki, Tomohiro Kose, Takashi Asada, Kuniaki
Kawata
Abstract
Magnetic carbonaceous materials were produced by carbonization of a cation exchange resin loaded with ferrous or ferric iron and activation using sieved oyster shell as the activation agent. The magnetic carbonaceous material with the maximum magnetic flux density on every axis (ESS-1) was obtained from the ferric-loaded resin by carbonization at 700 °C, followed by activation with the oyster shell at 900 °C, and magnetization. A separate step of carbonization and activation appears to cause more of a reduction reaction of Fe to form γ-Fe2O3. The Fe compound in the magnetic carbonaceous material was identified from the XRD pattern as mainly γ-Fe2O3. The magnetic flux density on every axis increased linearly as the amount of the oyster shell increased. Moreover, the adsorption ability of the products was evaluated for pesticides and metal ions. Both ESS-1 and a carbonaceous material obtained from the resin without ferric ion (RC) appear to have the highest adsorption ability for lead. Furthermore, the adsorption ability of ESS-1 might decrease by blockages of the pores with the loaded Fe compounds.

21.
Homogenization of random anisotropy properties in polycrystalline magnetic materials Original Research Article
Physica B: Condensed Matter, In Press, Corrected Proof, Available online 8 July 2011
Oriano Bottauscio, Valeria Chiadò Piat, Michela Eleuteri, Luca Lussardi, Alessandra Manzin
Abstract
This paper is devoted to the determination of the equivalent anisotropy properties of polycrystalline magnetic materials, modelled by an assembly of monocrystalline grains with a stochastic spatial distribution of easy axes. The mathematical theory of Γ-convergence is applied to homogenize the anisotropic term in the Gibbs free energy. The procedure is validated focusing on the micromagnetic computation of reversal processes in polycrystalline magnetic thin films.
Keywords: Micromagnetics; Polycrystalline magnetic materials; Random anisotropy; Homogenization

22.
Micrometer scale resolution of materials by stray-field Magnetic Resonance Imaging Original Research Article
Journal of Magnetic Resonance, Volume 211, Issue 1, July 2011, Pages 60-66
Maxime Van Landeghem, Bruno Bresson, Bernhard Blümich, Jean-Baptiste d’Espinose de Lacaillerie
Abstract
As Magnetic Resonance Imaging devices are becoming more and more powerful, resolutions as small as 10 μm can now be obtained. But, this is only possible when systems with slow transverse relaxation rates, like living tissues, are investigated. In this case, the time available for gradients space-encoding is long, and high k values can be reached in the Fourier domain. However, numerous materials have fast relaxation rates, thus limiting the spatial resolution to a few hundreds of microns. The Stray Field Imaging technique has solved this problem by using a very high (typically 5000 G/cm) static gradient. Consequently, the trajectory in k space is accelerated and it is possible, in principle, to reach a micrometer resolution in a few hundreds of microseconds. Most of the time, however, only resolutions in the millimeter range can be achieved due to mispositioning of the sample within the static magnetic field. Here, we show that by finely mapping the magnetic field and precisely positioning the sample, it is possible with a standard spectrometer to reach a micrometer resolution even on very fast relaxing materials.

23.
Anisotropy of hyperfine interactions as a tool for interpretation of NMR spectra in magnetic materials Original Research Article
Solid State Nuclear Magnetic Resonance, Volume 40, Issue 1, July 2011, Pages 27-30
V. Chlan, H. Štěpánková, R. Řezníček, P. Novák
Abstract
Approach for interpretation of nuclear magnetic resonance (NMR) spectra in magnetic materials is presented, consisting in employing the anisotropy of hyperfine interaction. The anisotropic parts of hyperfine magnetic fields on 57Fe nuclei are calculated ab initio for a model example of lithium ferrite and utilized to assign the experimental NMR spectral lines to iron sites in the crystal structure.

24.
Application of derivatized magnetic materials to the separation and the preconcentration of pollutants in water samples Review Article
TrAC Trends in Analytical Chemistry, Volume 30, Issue 7, July-August 2011, Pages 1095-1108
Ligang Chen, Ting Wang, Jia Tong
Abstract
Monitoring pollutants in water samples is a challenge to analysts. In recent years, separation technology based on magnetic materials has received considerable attention. This article reviews the literature dealing with the application of magnetic materials, combined with other materials (e.g., silica, octadecylsilane, polymers and surfactants), to the separation and the preconcentration of pollutants in water samples. The magnetic extraction method is not only convenient, economical and highly efficient, but it also overcomes problems with conventional solid-phase extraction, (e.g., packing of sorbent into the column and time-consuming loading of large-volume samples).
Keywords: Magnetic extraction; Magnetic material; Octadecylsilane; Pollutant; Polymer; Preconcentration; Separation; Silica; Surfactant; Water sample

25.
MSWI boiler fly ashes: Magnetic separation for material recovery Original Research Article
Waste Management, Volume 31, Issue 7, July 2011, Pages 1505-1513
Aurore De Boom, Marc Degrez, Paul Hubaux, Christian Lucion
Abstract
Nowadays, ferrous materials are usually recovered from Municipal Solid Waste Incineration (MSWI) bottom ash by magnetic separation. To our knowledge, such a physical technique has not been applied so far to other MSWI residues. This study focuses thus on the applicability of magnetic separation on boiler fly ashes (BFA). Different types of magnet are used to extract the magnetic particles. We investigate the magnetic particle composition, as well as their leaching behaviour (EN 12457-1 leaching test). The magnetic particles present higher Cr, Fe, Mn and Ni concentration than the non-magnetic (NM) fraction. Magnetic separation does not improve the leachability of the NM fraction. To approximate industrial conditions, magnetic separation is also applied to BFA mixed with water by using a pilot. BFA magnetic separation is economically evaluated. This study globally shows that it is possible to extract some magnetic particles from MSWI boiler fly ashes. However, the magnetic particles only represent from 23 to 120 g/kg of the BFA and, though they are enriched in Fe, are composed of similar elements to the raw ashes. The industrial application of magnetic separation would only be profitable if large amounts of ashes were treated (more than 15 kt/y), and the process should be ideally completed by other recovery methods or advanced treatments.

26.
Preparation of magnetic polymer material with phosphate group and its application to the enrichment of phosphopeptides Original Research Article
Journal of Chromatography A, Volume 1218, Issue 25, 24 June 2011, Pages 3845-3853
Xiao-Shui Li, Jian-Hong Wu, Yong Zhao, Wei-Ping Zhang, Qiang Gao, Lin Guo, Bi-Feng Yuan, Yu-Qi Feng
Abstract
As one of the most important post-translational modifications (PTM), reversible phosphorylation of protein is involved in many cellular processes. Enrichment and separation of phosphopeptides have become essential for large-scale identification of protein phosphorylation by mass spectrometry. In this work, five magnetic polymer materials with different numbers of phosphate groups were fabricated using a simple polymeric method and their abilities to enrich phosphopeptides were investigated. Our results showed that the enrichment efficiency is closely related to the number of phosphate groups attached to magnetic polymer sorbent. Under optimized condition (3% trifluoroacetic acid and 80% acetonitrile), magnetic polymer-particles with appropriate proportion of phosphate groups (Fe3O4@p(VPA-EDMA-1)-Zr4+) showed high performance for extracting phosphopeptides from complex peptides mixture of standard protein digestion. In this regard, a total of 988 unique phosphopeptides were successfully identified from proteolytic digestion of HeLa cell extracts by employing magnetic polymer-particles combined with nano-RPLC–MS/MS analysis.
Keywords: Magnetic polymer; Phosphate group; Enrichment of phosphopeptides; Mass spectrometry

27.
Modeling of magnetic material displaying magnetic aftereffect with slow decay rates Original Research Article
Physica B: Condensed Matter, In Press, Corrected Proof, Available online 24 June 2011
S. Gu, Y. Jin, P. Chen, C. Yan, E. Della Torre, L.H. Bennett
Abstract
For magnetic materials that display slow decay rates, the entire relaxation process cannot be observed experimentally within a reasonable time interval. While magnetic aftereffect behavior has been understood and analyzed quantitatively in general, the important parameters of magnetic materials with slow decay cannot be easily extracted. We present comprehensive experimental characterization of time, field, and temperature dependence of magnetic properties of a magnetic nanocomposite, which exhibits slow decay. Based on the measurement results and previously developed Preisach–Arrhenius model, we propose an analytical model that can predict the shape of the entire aftereffect curves at different temperatures with only the major hysteresis loop and one aftereffect curve at a specific holding field within the region of interest. The model is validated with both simulated data and measured data. This model allows the derivation of an analytical formula for the time variation of the magnetization based on a Gaussian distribution.
Keywords: Magnetic aftereffect; Decay rate; Preisach function; Numerical modeling

28.
Experimental results for a magnetic refrigerator using three different types of magnetocaloric material regenerators Original Research Article
International Journal of Refrigeration, Volume 34, Issue 4, June 2011, Pages 1132-1140
K. Engelbrecht, C.R.H. Bahl, K.K. Nielsen
Abstract
Magnetic refrigeration is a potentially environmentally-friendly alternative to vapor compression technology because it has a potentially higher coefficient of performance and does not use a gaseous refrigerant. The active magnetic regenerator refrigerator is currently the most common magnetic refrigeration device for near room temperature applications, and it is driven by the magnetocaloric effect in the regenerator material. Several magnetocaloric materials with potential magnetic refrigeration applications have recently been developed and characterized; however, few of them have been tested in an experimental device. This paper compares the performance of three magnetocaloric material candidates for AMRs, La(Fe,Co,Si)13, (La,Ca,Sr)MnO3 and Gd, in an experimental active magnetic regenerator with a parallel plate geometry. The performance of single-material regenerators of each magnetocaloric material family were compared. In an attempt to improve system performance, graded two-material regenerators were made from two different combinations of La(Fe,Co,Si)13 compounds having different magnetic transition temperatures. One combination of the La(Fe,Co,Si)13 materials yielded a higher performance, while the performance of the other combination was lower than the single-material regenerator. The highest no-load temperature span was achieved by the Gd regenerator.
Keywords: Magnetic refrigerator; Regenerator; Magnetic property; Experimentation

29.
Fast flip to ferromagnetic phase: Magnetic Materials
Materials Today, Volume 14, Issue 6, June 2011, Page 245
Stewart Bland

30.
Theory goes for a spin: Magnetic Materials
Materials Today, Volume 14, Issue 6, June 2011, Page 246
Katerina Busuttil

31.
Characterisation of novel magnetic materials using the USANSPOL technique Original Research Article
Physica B: Condensed Matter, Volume 406, Issue 12, June 2011, Pages 2401-2404
E. Jericha, G. Badurek, R. Grössinger
Abstract
USANSPOL is a novel ultra-small-angle scattering technique with polarised neutrons for investigation of magnetic materials. It represents a polarised neutron extension to traditional USANS which works with unpolarised neutrons. The high angular resolution of this technique relies on the narrow reflection width of perfect crystal reflections and is employed in a double-crystal diffractometer. Corresponding to the μrad resolution of the set-up, micro-structures of the order of a few tenths of a micrometre up to a few tens of micrometres may be investigated. Neutron polarisation is achieved by insertion of birefringent magnetic prisms between the monochromator crystal and the sample. Rocking the analyser crystal produces a scattering pattern for both neutron spin states in a single measurement but well separated in reciprocal space. By this technique, we have recently studied various amorphous Galfenol soft-magnetic ribbons which were produced by spinning from melt at different manufacturing conditions. USANSPOL allows for a determination of domain sizes of the non-magnetised samples and a study of the growing of magnetically homogeneous regions with increasing externally applied magnetic field. The manufacturing process of the ribbons is reflected in the magnetic micro-structure of the different specimens.

32.
New heat generation material in AC magnetic field for Y3Fe5O12-based powder material synthesized by reverse coprecipitation method
Materials Letters, Volume 65, Issue 10, 31 May 2011, Pages 1454-1456
Hiromichi Aono, Kenji Moritani, Takashi Naohara, Tsunehiro Maehara, Hideyuki Hirazawa, Yuji Watanabe
Abstract
We found the most promising powder material for the application of the thermal coagulation therapy for the treatment of cancerous tissues. The maximum heat generation ability (ΔT = 40–77 °C, 370 kHz, 1.77 kA•m− 1) was obtained for the powder materials by the calcination at 1100 °C for the Y3 − XGdXFe5O12 system. This ΔT value is higher than ca. ΔT = 30 °C in same magnetic field for fine FeFe2O4 particles as the candidate material for this type of therapy. The particle growth with the formation of the cubic single phase might influence to the high heat generation. As an unexpected result, the Gd3Fe5O12 (X = 3) has no heat generation ability in an AC magnetic field.
Keywords: Magnetic materials; Ceramics; Y3Fe5O12; Heat generation ability; AC magnetic field; Coagulation therapy

33.
Independently tunable transmission-type magneto-optical isolators based on multilayers containing magnetic materials
Physics Letters A, Volume 375, Issue 22, 30 May 2011, Pages 2185-2188
Tingting Sun, Jie Luo, Ping Xu, Lei Gao
Abstract
We investigate the magneto-optical (MO) properties of multilayers containing several magnetic defects. Our numerical simulations show that each MO defect mode can be tuned independently by adjusting the structural parameters of magnetic materials. In addition, giant Faraday rotation can be obtained. Our results indicate that the structure may have potential applications for independently tunable multichannel MO isolators.

34.
Hydrogenation-induced variation in crystal structure and heat capacity of magnetic regenerative material Er3Ni Original Research Article
Cryogenics, Volume 51, Issue 5, May 2011, Pages 214-217
T. Jin, C.H. Li, K. Tang, L.X. Chen, B. Xu, G.B. Chen
Abstract
In order to analyze the influence of hydrogenation on magnetic regenerative material Er3Ni, the structures of Er3Ni and its hydrides Er3NiHx are tested by X-ray diffraction (XRD), and their magnetic properties and heat capacities are measured by a magnetic property measurement system (MPMS) and by a physical property measurement system (PPMS), respectively. The results show that different crystal structures can be formed by the hydrogenation at 293 K, while the Er3NiHx does not go through magnetic transition above 2 K. The Er3NiHx exhibits different specific heat features with that of original compound Er3Ni, which could be attributed to the absence of magnetic transition and other effects caused by hydrogenation. The insertion of hydrogen atoms can lead to a larger specific heat than that of Er3Ni in some certain temperature range.

35.
Spin liquid phase diagram revealed: Magnetic Materials
Materials Today, Volume 14, Issue 5, May 2011, Page 188
Andrea Taroni

36.
Spin ice gives currents life: Magnetic Materials
Materials Today, Volume 14, Issue 4, April 2011, Page 127
Laurie Donaldson

37.
Good (next-nearest) neighbors: Magnetic Materials
Materials Today, Volume 14, Issue 4, April 2011, Page 132
Stewart Bland

38.
Structural, electronic and magnetic properties of negative thermal expansion material Mn3Cu1−xSnxN Original Research Article
Physica B: Condensed Matter, Volume 406, Issues 6-7, 15 March 2011, Pages 1222-1225
L. Hua, J. He
Abstract
We have investigated the structural, electronic and magnetic properties of Mn3Cu1−xSnxN(x=0, 0.5) using first-principles density functional theory within the generalized gradient approximation (GGA) + U schemes. The crystal structure of the compounds is tetragonal crystal for x=0 while it is a cubic crystal for x=0.5. Our spin-polarized calculations give a metallic ground state for the x= 0, 0.5 in agreement with experiments. From the charge density and density of states(DOS), the coupling between Sn 5p with Mn 3d and spin geometrical frustration effect are the main reasons for magnetic transition in Mn3Cu1−xSnxN.

39.
Ferromagnetism in thin-walled hollow spheres of non-magnetic inorganic materials Original Research Article
Chemical Physics Letters, Volume 504, Issues 4-6, 10 March 2011, Pages 189-192
Nitesh Kumar, Dinesh Jagadeesan, Premlal B. Pillai, Melby Chacko, M. Eswaramoorthy, A. Sundaresan
Abstract
To study defect origin of ferromagnetism, hollow spheres are better candidates as they are less agglomerated and has both sides of the wall free, as compared to nanoparticles and thin films respectively. Our results show improved magnetic properties of GaN, ZnAl2O4 and MgO hollow spheres over their earlier reported nanoparticle counterparts. Photoluminescence spectroscopy supports our magnetic findings.

40.
Corrosion behavior of magnetic refrigeration material La–Fe–Co–Si in distilled water Original Research Article
Journal of Alloys and Compounds, Volume 509, Issue 8, 24 February 2011, Pages 3627-3631
Min Zhang, Yi Long, Rong-chang Ye, Yong-qin Chang

41.
Fast neutron irradiation of high-Tc superconducting materials engineered for magnetic field and THz photon detection Original Research Article
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, In Press, Corrected Proof, Available online 1 February 2011
Laura Gozzelino, Roberto Gerbaldo, Gianluca Ghigo, Francesco Laviano, Enrica Mezzetti, Roberto Cherubini, Bruno Minetti

42.
Experimental analysis of a two-material active magnetic regenerator Original Research Article
International Journal of Refrigeration, Volume 34, Issue 1, January 2011, Pages 178-191
D.S. Arnold, A. Tura, A. Rowe
Abstract
Experimental results of an active magnetic regenerator (AMR) composed of two equal volumes of gadolinium and Gd0.85Er0.15 using 2 T and 5 T are reported. Drive forces and system losses are measured as a function of thermal load and magnetic field. Metrics for coefficient of performance and efficiency are defined and used to distinguish between regenerator and device performance. Results suggest the largest temperature spans are expected to occur when each material is operating with its average temperature near their Curie temperatures. Force measurements indicate that mechanical losses and pumping power are the most significant contributions to network while the net magnetic work is too small to be resolved. COP values for the magnetic cycle are as high as 2.4 while efficiencies are all less than 0.15. A maximum exergetic cooling of 1.94 W is estimated with a corresponding specific exergetic cooling power of 23 W T−1L−1.
Keywords: Magnetic refrigeration; COP-exergy; Performance; Gadolinium-cost

43.
A new ferromagnetic hysteresis model for soft magnetic composite materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 323, Issue 1, January 2011, Pages 67-71
Bogomir Zidarič, Damijan Miljavec
Abstract
A new ferromagnetic hysteresis model for soft magnetic composite materials based on their specific properties is presented. The model relies on definition of new anhysteretic magnetization based on the Cauchy–Lorentz distribution describing the maximum energy state of magnetic moments in material. Specific properties of soft magnetic composite materials (SMC) such as the presence of the bonding material, different sizes and shapes of the Fe particles, level of homogeneity of the Fe particles at the end of the SMC product treatment, and achieved overall material density during compression, are incorporated in both the anhysteretic differential magnetization susceptibility and the irreversible differential magnetization susceptibility. Together they form the total differential magnetization susceptibility that defines the new ferromagnetic hysteresis model. Genetic algorithms are used to determine the optimal values of the proposed model parameters. The simulated results show good agreement with the measured results.
Keywords: Composite materials; Hysteresis model; Powder metallurgy; Magnetization; Magnetic measurements

44.
Hybrid materials composed of tetravanadate motifs: Synthesis, structure and magnetic properties of the open framework structure solids [{M(C5H5N)4}2]V4O12 (M = Cu, Co) Original Research Article
Inorganica Chimica Acta, Volume 363, Issue 15, 10 December 2010, Pages 4307-4312
M. Ishaque Khan, Renata C. Nome, Naga Ravikanth Putrevu, James H. McNeely, Brant Cage, Robert J. Doedens

45.
2-dof non-linear dynamics of a rotor suspended in the magneto-hydrodynamic field in the case of soft and rigid magnetic materials Original Research Article
International Journal of Non-Linear Mechanics, Volume 45, Issue 9, November 2010, Pages 919-930
Jan Awrejcewicz, Larisa P. Dzyubak
Abstract
Non-linear dynamics of a high-speed rotor symmetrically supported on the magneto-hydrodynamic bearing is analyzed. In the case of soft magnetic materials the method of multiple scales [1] is applied. Non-resonant and primary resonance cases with and without internal resonance are illustrated and discussed. In the case of rigid magnetic materials the hysteretic properties are taken into consideration by means of the Bouc–Wen hysteretic model. In order to characterize the hysteretic close-loop control of the rotor motion, instability regions as well as the amplitude level contours of vertical and horizontal vibrations of the rotor are obtained in the form suitable for engineering applications, i.e. in the ‘frequency-amplitude’ parametric plane.
Keywords: Rotor; Magneto-hydrodynamic bearing; Hysteresis; Control; Stability

46.
Design of novel magnetic materials based on ZrCuSiAs-like semiconducting pnictide-oxides from first-principles calculations
Solid State Communications, Volume 150, Issues 41-42, November 2010, Pages 2069-2071
V.V. Bannikov, I.R. Shein, A.L. Ivanovskii
Abstract
We assumed that significant enlargement of the functional properties of the family of quaternary ZrCuSiAs-like pnictide-oxides, often called also 1111 phases, which are known now first of all as parent phases for new FeAs superconductors, may be achieved by replacement of non-magnetic ions by magnetic ions in semiconducting ZrCuSiAs-like phases. We checked this assumption by means of first-principles FLAPW–GGA calculations using a wide-band-gap semiconductor YZnAsO doped with Mn, Fe, and Co as an example. Our main finding is that substitution of Mn, Fe, and Co for Zn leads to drastic transformations of electronic and magnetic properties of the parent material: as distinct from the non-magnetic YZnAsO, the examined doped phases Y Zn0.89Mn0.11AsO, Y Zn0.89Fe0.11AsO, and Y Zn0.89Co0.11AsO behave as a magnetic semiconductor, a magnetic half-metal or as a magnetic gapless semi-metal, respectively.
Keywords: A. YZnAsO; C. Doping; D. Novel magnetic materials; E. ab initio calculations

47.
Monte Carlo study of the spin transport in magnetic materials Original Research Article
Computational Materials Science, Volume 49, Issue 4, Supplement, October 2010, Pages S204-S209
Y. Magnin, K. Akabli, H.T. Diep, I. Harada
Abstract
The resistivity in magnetic materials has been theoretically shown to depend on the spin–spin correlation function which in turn depends on the magnetic field, the density of conduction electron, the magnetic ordering stability, etc. However, these theories involved a lot of approximations, so their validity remained to be confirmed. The purpose of this work is to show by newly improved extensive Monte Carlo (MC) simulation the resistivity of the spin resistivity from low-T ordered phase to high-T paramagnetic phase in ferromagnetic and antiferromagnetic films. We take into account the interaction between the itinerant spins and the localized lattice spins as well as the interaction between itinerant spins themselves. We show that in ferromagnets the resistivity shows a sharp peak at the magnetic phase transition in agreement with previous theories in spite of their numerous approximations. Resistivity in antiferromagnets on the other hand shows no peak for the SC, BCC and diamond lattices. Discussion on the origin of these resistivity behaviors is given.
Keywords: Spin transport; Monte Carlo simulation; Magnetic resistivity; Magnetic materials

48.
Supramolecular coordination chemistry of aromatic polyoxalamide ligands: A metallosupramolecular approach toward functional magnetic materials Review Article
Coordination Chemistry Reviews, Volume 254, Issues 19-20, October 2010, Pages 2281-2296
Marie-Claire Dul, Emilio Pardo, Rodrigue Lescouëzec, Yves Journaux, Jesús Ferrando-Soria, Rafael Ruiz-García, Joan Cano, Miguel Julve, Francesc Lloret, Danielle Cangussu, Cynthia L.M. Pereira, Humberto O. Stumpf, Jorge Pasán, Catalina Ruiz-Pérez
Abstract
The impressive potential of the metallosupramolecular approach in designing new functional magnetic materials constitutes a great scientific challenge for the chemical research community that requires an interdisciplinary collaboration. New fundamental concepts and future applications in nanoscience and nanotechnology will emerge from the study of magnetism as a supramolecular function in metallosupramolecular chemistry. Our recent work on the rich supramolecular coordination chemistry of a novel family of aromatic polyoxalamide (APOXA) ligands with first-row transition metal ions has allowed us to move one step further in the rational design of metallosupramolecular assemblies of increasing structural and magnetic complexity. Thus, we have taken advantage of the new developments of metallosupramolecular chemistry and, in particular, the molecular-programmed self-assembly methods that exploit the coordination preferences of paramagnetic metal ions and suitable designed polytopic ligands. The resulting self-assembled di- and trinuclear metallacyclic complexes with APOXA ligands, either metallacyclophanes or metallacryptands, are indeed ideal model systems for the study of the electron exchange mechanism between paramagnetic metal centers through extended π-conjugated aromatic bridges. So, the influence of different factors such as the topology and conformation of the bridging ligand or the electronic configuration and magnetic anisotropy of the metal ion have been investigated in a systematic way. These oligonuclear metallacyclic complexes can be important in the development of a new class of molecular magnetic devices, such as molecular magnetic wires (MMWs) and switches (MMSs), which are major goals in the field of molecular electronics and spintronics. On the other hand, because of their metal binding capacity through the outer carbonyl-oxygen atoms of the oxamato groups, they can further be used as ligands, referred to as metal–organic ligands (MOLs), toward either coordinatively unsaturated metal complexes or fully solvated metal ions. This well-known “complex-as-ligand” approach affords a wide variety of high-nuclearity metal–organic clusters (MOCs) and high-dimensionality metal–organic polymers (MOPs). The judicious choice of the oligonuclear MOL, ranging from mono- to di- and trinuclear species, has allowed us to control the overall structure and magnetic properties of the final oxamato-bridged multidimensional (nD, n = 0–3) MOCs and MOPs. The intercrossing between short- (nanoscopic) and long-range (macroscopic) magnetic behavior has been investigated in this unique family of oxamato-bridged metallosupramolecular magnetic materials expanding the examples of low-dimensional, single-molecule (SMMs) and single-chain (SCMs) magnets and high-dimensional, open-framework magnets (OFMs), which are brand-new targets in the field of molecular magnetism and materials science.
Keywords: Metallosupramolecular chemistry; Metal–organic clusters; Metal–organic polymers; Molecular magnets; Polytopic ligands; Self-assembly

49.
Magnetic characteristics of HPT deformed soft-magnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 322, Issue 20, October 2010, Pages 2984-2988
S. Scheriau, M. Kriegisch, S. Kleber, N. Mehboob, R. Grössinger, R. Pippan
Abstract
Five sets of soft-magnetic metals, such as pure Fe, pure Ni, Fe-3 wt% Si, Fe-6.5 wt% Si and Fe-17 wt% Co, were subjected to high pressure torsion (HPT) up to strain levels where a saturation of the microstructural refinement is observed. Following HPT at 77, 293 and 723 K, transmission electron microscopy (TEM) was used to study the grain size and grain shape of the severely deformed metals. The coercivity HC was characterized in a magnetic closed system by using ring shaped samples. Magnetic measurements obtained on ring shaped samples give a much higher accuracy for determining the coercivity. Depending on the material the mean microstructural sizes in the steady state vary from 300 nm at 723 K to 30 nm at 77 K, respectively. The coercivity of the deformed materials first increases with decrease in grain size. Once the crystallite size is far below 100 nm the coercivity shows a strong decrease.
Keywords: HPT; Coercivity; Fe; Ni; Fe–Si; FeCo

50.
Study of the influence of simultaneous variation of magnetic material microstructural features on domain wall dynamics Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 322, Issue 20, October 2010, Pages 3101-3105
J.A. Perez-Benitez, L.R. Padovese
Abstract
The magnetic Barkhausen noise (MBN) is a phenomenon sensitive to several kinds of magnetic material microstructure changes, as well as to variations in material plastic deformation and stress. This fact stimulates the development of MBN-based non-destructive testing (NDT) techniques for analyzing magnetic materials, being the proposition of such a method, the main objective of the present study. The behavior of the MBN signal envelope, under simultaneous variations of carbon content and plastic deformation, is explained by the domain wall dynamics. Additionally, a non-destructive parameter for the characterization of each of these factors is proposed and validated through the experimental results.
Keywords: MBN decorrelation; Plastic deformation; Carbon content; Non-destructive method

51.
Elaboration of nickel nanoparticles by modified polyol process and their spark plasma sintering, characterization and magnetic properties of the nanoparticles and the dense nano-structured material Original Research Article
Materials Chemistry and Physics, Volume 123, Issues 2-3, 1 October 2010, Pages 821-828
A. Dakhlaoui Omrani, M.A. Bousnina, L.S. Smiri, M. Taibi, P. Leone, F. Schoenstein, N. Jouini

52.
Stretched Janus material: Magnetic materials
Materials Today, Volume 13, Issue 10, October 2010, Page 10
David Bradley

53.
They do it with mirrors: Magnetic materials
Materials Today, Volume 13, Issue 10, October 2010, Page 11
Katerina Busuttil

54.
Syntheses, crystal structures, and magnetic properties of two molecular materials by self-assembly of bis(maleonitriledithiolato)nickelate monoanion and substituted benzyltriphenylphosphinium Original Research Article
Journal of Molecular Structure, Volume 981, Issues 1-3, 24 September 2010, Pages 139-145
Xing Chen, Hai-Lian Zhou, Jing-Hua Lin, Qian Huang, Hong-Rong Zuo, Jia-Rong Zhou, Chun-Lin Ni, Xue-Lei Hu

55.
Influence of crossed electric and quantizing magnetic fields on the Einstein relation in nonlinear optical, optoelectronic and related materials: Simplified theory, relative comparison and suggestion for experimental determination Original Research Article
Physica B: Condensed Matter, Volume 405, Issue 18, 15 September 2010, Pages 4064-4078
S. Pahari, S. Bhattacharya, D. De, S.M. Adhikari, A. Niyogi, A. Dey, N. Paitya, S.C. Saha, K.P. Ghatak, P.K. Bose

56.
Magnets trump metallics: Magnetic Materials
Materials Today, Volume 13, Issue 9, September 2010, Page 13
Jonathan Agbenyega

57.
On effective electromagnetic parameters of artificial nanostructured magnetic materials Original Research Article
Photonics and Nanostructures - Fundamentals and Applications, Volume 8, Issue 4, September 2010, Pages 254-263
C.R. Simovski, S.A. Tretyakov
Abstract
In this paper we discuss effective material parameter description of new nanostructures designed to perform as artificial magnetic materials for visible light. Among these structures there are various split-ring resonators, dual-bar structures, fishnet layers and other geometries. Artificial magnetic response in these structures appears due to weak spatial dispersion effects, and it is important to study the conditions under which the magnetic response can be adequately measured with effective permeability tensor. On the examples of dual bars and split rings we show that this is possible only under some quite restrictive conditions. In the general case, more complicated constitutive relations with more effective material parameters need to be developed.
Keywords: Metamaterial; Electromagnetic characterization; Effective material parameters; Permeability; Spatial dispersion; Multipole media; Bianisotropic media

58.
On the two-dimensional thermoelectric power in quantum wells of non-parabolic materials under magnetic quantization Original Research Article
Superlattices and Microstructures, Volume 48, Issue 3, September 2010, Pages 257-275
S. Bhattacharya, S. Choudhury, K.P. Ghatak

59.
Modern sampling and analytical methods for the determination of trace elements in marine particulate material using magnetic sector inductively coupled plasma–mass spectrometry Original Research Article
Analytica Chimica Acta, Volume 676, Issues 1-2, 31 August 2010, Pages 15-27
Andrew R. Bowie, Ashley T. Townsend, Delphine Lannuzel, Tomas A. Remenyi, Pier van der Merwe

60.
Temperature dependence of the FMR absorption lines in viscoelastic magnetic materials Original Research Article
Journal of Alloys and Compounds, Volume 504, Issue 2, 20 August 2010, Pages 289-295
M.R. Dudek, N. Guskos, E. Senderek, Z. Roslaniec
Abstract
The magnetic properties of the viscoelastic materials filled with magnetic nanoparticles strongly depend on the viscosity of these materials. The time–temperature changes of the viscosity can affect the orientation ordering of the anisotropy axes of the magnetic nanoparticles after an external magnetic field is applied. In consequence, the absorption lines obtained in the ferromagnetic resonance experiment (FMR) will possess an additional temperature dependence through the viscosity of the materials under consideration. The particular case of the temperature dependence of the FMR signal detected from the γ-Fe2O3 (maghemite) magnetic nanoparticles dispersed at low concentration (0.1 wt.%) in a poly(ether-ester) multiblock copolymer (PEN-block-PTMO)) matrix has been investigated. A strong increase of the resonance line amplitude is observed with increasing temperature. We note also two qualitatively different temperature dependences of the magnetic resonance field at low and high temperatures. A simplified theoretical model of a single cluster consisting of N magnetic nanoparticles in an elastic polymer matrix is introduced to explain these temperature dependences of the absorption lines. The model is based on the stochastic version of the Lifshitz–Landau equation for nanoparticle magnetization.

61.
A two-dimensional magnetic hybrid material based on intercalation of a cationic Prussian blue analog in montmorillonite nanoclay Original Research Article
Journal of Colloid and Interface Science, Volume 348, Issue 2, 15 August 2010, Pages 393-401
Dimitrios Gournis, Christina Papachristodoulou, Enrico Maccallini, Petra Rudolf, Michael A. Karakassides, Dimitrios T. Karamanis, Marie-Hélène Sage, Thomas T.M. Palstra, Jean-François Colomer, Konstantinos D. Papavasileiou, Vasilios S. Melissas, Nicolaos H. Gangas

62.
Joint Conferences on Advanced Materials:Functional and Nanonstructured Materials — FNMA’09Intermolecular and Magnetic Interactions in Matter — IMIM’0927–30 September 2009, Sulmona-L’Aquila, Italy
Journal of Non-Crystalline Solids, Volume 356, Issues 37-40, 15 August 2010, Pages vi-vii

63.
Magnetic properties of B and AB-spinels Zn1−xMxFe2O4 (M = Ni, Mg) materials Review Article
Journal of Alloys and Compounds, Volume 503, Issue 2, 6 August 2010, Pages 299-302
R. Masrour, M. Hamedoun, A. Benyoussef

64.
A magnetically responsive material of single-walled carbon nanotubes functionalized with magnetic ionic liquid Original Research Article
Carbon, Volume 48, Issue 9, August 2010, Pages 2501-2505
Xiaowei Pei, Ye Hai Yan, Liangyu Yan, Pan Yang, Junling Wang, Rong Xu, Mary B. Chan-Park

65.
Synthesis and magnetic properties of Co1−xZnxFe2O4+γ nanoparticles as materials for magnetic fluid hyperthermia Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 322, Issue 16, August 2010, Pages 2386-2389
M. Veverka, P. Veverka, Z. Jirák, O. Kaman, K. Knížek, M. Maryško, E. Pollert, K. Závěta
Abstract
Nanoparticles of the single spinel phase Co1−xZnxFe2O4+γ of mean size 3–23 nm, as determined by X-ray diffraction analysis, were synthesized by the co-precipitation method followed by a temperature treatment. Magnetic studies carried out in the range of 4.5–550 K revealed gradual transition from ferrimagnetic to superparamagnetic to paramagnetic behaviour depending on the composition and particle size. The observed behaviour indicates a broad distribution of volume sizes of the nanoparticles. Particular importance can be ascribed to the composition of x=0.6 where the observed transition temperature to the paramagnetic state at 310–334 K suggests applicability of this material for magnetic fluid hyperthermia in a self-controlled regime.

66.
Paired-pulse transcranial magnetic stimulation over the dorsolateral prefrontal cortex interferes with episodic encoding and retrieval for both verbal and non-verbal materials Original Research Article
Brain Research, Volume 1344, 16 July 2010, Pages 148-158
Geneviève Gagnon, Sophie Blanchet, Simon Grondin, Cyril Schneider

67.
Computation of surface effects and its influence to critical magnetic field in materials Original Research Article
Computational Materials Science, Volume 49, Issue 1, Supplement, July 2010, Pages S25-S28
Fahrudin Nugroho, Pekik Nurwantoro, S.U. Agung Bambang, K. Dian Artha

68.
Polynitrile anions as ligands: From magnetic polymeric architectures to spin crossover materials Review Article
Coordination Chemistry Reviews, Volume 254, Issues 13-14, July 2010, Pages 1468-1478
Samia Benmansour, Chahlae Atmani, Fatima Setifi, Smaïl Triki, Mathieu Marchivie, Carlos J. Gómez-García

69.
Structural, magnetic, and electrochemical studies on lithium insertion materials LiNi1−xCoxO2 with 0≤x≤0.25 Original Research Article
Journal of Solid State Chemistry, Volume 183, Issue 7, July 2010, Pages 1726-1732
Kazuhiko Mukai, Jun Sugiyama, Yoshifumi Aoki

70.
Magnetic hysteresis loops in molecular-based magnetic materials AFeIIFeIII(C2O4)3
Original Research Article
Physica A: Statistical Mechanics and its Applications, Volume 389, Issue 11, 1 June 2010, Pages 2227-2233
Wei Jiang, Veng-cheong Lo, Bao-Dong Bai, Jun Yang
Abstract
A molecular-based magnetic material AFeIIFeIII(C2O4)3 (A = organic cation) with a honeycomb structure is studied. The molecular-based magnet system consists of mixed spin-2 and spin- 5/2 honeycomb lattices with ferrimagnetic interlayer coupling. The magnetization, hysteresis loops and initial susceptibility have been calculated using a numerical method which includes both the longitudinal and transverse fields. We investigated the magnetic reversal of the system and found the existence of triple hysteresis loop patterns, affected by the anisotropy, longitudinal and transverse fields, and interlayer and intralayer exchange.

71.
Magnetic force memory effect using a magnetostrictive material and a shape memory piezoelectric actuator composite Original Research Article
Sensors and Actuators A: Physical, Volume 161, Issues 1-2, June 2010, Pages 266-270
Takeshi Morita, Tomoya Ozaki

72.
Quantum dots, and silicon herald new functionality: Magnetic materials
Materials Today, Volume 13, Issue 5, May 2010, Page 10
Jonathan Agbenyega

73.
On the geometry control of magnetic devices: Impact of photo-resist profile, shadowing effect, and material properties Original Research Article
Vacuum, Volume 84, Issue 9, 19 April 2010, Pages 1075-1079
Xilin Peng, Zhongyan Wang, Yongxiong Lu, Brendan Lafferty, Thomas McLaughlin, Mark Ostrowski

74.
Synthesis of a hybrid material consisting of magnetic iron-oxide nanoparticles and carbon nanotubes as a gas adsorbent Original Research Article
Carbon, Volume 48, Issue 5, April 2010, Pages 1397-1404
Pei-Ling Lee, Yu-Kai Chiu, Yuh-Chang Sun, Yong-Chien Ling

75.
Magnetic properties of lunar materials: Meteorites, Luna and Apollo returned samples
Earth and Planetary Science Letters, Volume 292, Issues 3-4, 1 April 2010, Pages 383-391
P. Rochette, J. Gattacceca, A.V. Ivanov, M.A. Nazarov, N.S. Bezaeva

76.
New high dielectric constant materials for tailoring the distribution at high magnetic fields
Journal of Magnetic Resonance, Volume 203, Issue 2, April 2010, Pages 323-327
K. Haines, N.B. Smith, A.G. Webb

77.
Magnetic measurements for evaluation of radiation damage on nuclear reactor materials Original Research Article
Nuclear Engineering and Design, Volume 240, Issue 4, April 2010, Pages 722-725
S. Pirfo Barroso, M. Horváth, Á. Horváth

78.
TEM and electron holography analyses of granular and thin layered Cu–Co magnetic materials Original Research Article
Ultramicroscopy, Volume 110, Issue 5, April 2010, Pages 433-437
B. Dubiel, D. Wolf, A. Czyrska-Filemonowicz
Abstract
The paper shows the examples of application of transmission electron microscopy (TEM) techniques for characterization of two types of copper–cobalt magnetic nanomaterials: Cu-10 wt% Co granular giant magnetoresistance (GMR) thin ribbons and thin nanocrystalline Co films deposited on Cu substrate. Quantitative TEM microstructural analyses were used for determination of Co particle size distributions in GMR ribbons. It was demonstrated that the relative resistivity depends on the mean diameter of the cobalt nanoparticles. For nanocrystalline thin Co layers, off-axis electron holography was used to investigate their magnetic structure. The mean in-plane component of the magnetic field in cobalt was calculated from the phase gradient.

79.
Electronic structures and magnetic properties of Zn-doped colossal magnetoresistance materials Fe1-xZnxCr2S4
Physics Letters A, Volume 374, Issues 13-14, 29 March 2010, Pages 1555-1559
Q.F. Li, L.F. Chen, J.G. Yin

80.
Magnetic materials from co-precipitated ferrite nanoparticles Original Research Article
Materials Science and Engineering: B, Volume 167, Issue 2, 15 March 2010, Pages 85-90
V. Musat, O. Potecasu, R. Belea, P. Alexandru
Abstract
Some of recent technological advances in electronics need very compact magnetic materials. The paper presents the morphology and the magnetic properties of very dense polycrystalline magnetic materials obtained from co-precipitated manganese ferrite nanoparticles. The ferrite nanoparticles, with average diameter in the range of 13–25 nm, were obtained through an original low-cost co-precipitation route from aqueous solution of Mn2+ and Fe3+ ions generated by redox reactions between stoichiometric amounts of MnO2 (piroluzite) and FeSO4•7H2O raw materials. Very dense homogeneous polycrystalline magnetic materials with high square hysteresis loop (Br/Bs = 0.91) and low intrinsic coercivity were obtained using the co-precipitated un-doped manganese ferrite nanoparticles.
Keywords: Co-precipitation; Nanoparticle; Manganese ferrite; Compact magnetic material; Magnetic anisotropy

81.
Electrical conduction property of molecular magnetic material—{N(n-C4H9)4[Fe(II)Fe(III)(C2O4)3]}∞: Before and after thermal degradation Original Research Article
Physica B: Condensed Matter, Volume 405, Issue 6, 15 March 2010, Pages 1546-1550
A. Bhattacharjee, D. Bhakat, M. Roy, J. Kusz
Abstract
Electrical conduction properties of a molecular magnetic system {(cation)[Fe(II)Fe(III)(C2O4)3]}∞ with three different cations—N(n-C4H9)4+, N(n-C3H7)4+ and As(C6H5)4+ have been studied to understand the nature of electrical conduction in this molecular system as well as to explore any effect of the cation size on it. All the compounds are observed to be semiconducting in nature and their room temperature conductivity is of 10−15 S cm−1 order. Results indicate that the electrical conductivity as well as the activation energy of this system depends on the size of the cations used. Moreover, semiconducting iron oxide of hematite nature was obtained through the thermal degradation of {N(n-C4H9)4[Fe(II)Fe(III)(C2O4)3]}∞. The degraded material consisted of rod-like crystals of average length and diameter 350 and 140 nm, respectively.
Keywords: Molecular magnetic material; Oxalate; Semiconductor; Thermal degradation; Hematite

82.
Neutrons confirm Newton's predictions: Magnetic Materials
Materials Today, Volume 13, Issue 3, March 2010, Page 8
Andrea Taroni

83.
New ceramic material that harnesses the power from body movements: Magnetic Materials
Materials Today, Volume 13, Issue 3, March 2010, Page 9
Laurie Donaldson

84.
Spin reorientation process in Er2Fe14C magnetic material Original Research Article
Journal of Alloys and Compounds, Volume 490, Issues 1-2, 4 February 2010, Pages 11-14
A.T. Pędziwiatr, B.F. Bogacz, K. Krawiec, S. Wróbel

85.
Three-pulse spin echo signals from quadrupolar nuclei in magnetic materials Original Research Article
Solid State Nuclear Magnetic Resonance, Volume 37, Issues 1-2, February-April 2010, Pages 28-32
S.N. Polulyakh, N.A. Sergeev, A.I. Gorbovanov, V.N. Berzhansky
Abstract
The time evolutions of the three-pulse spin echo signals from quadrupolar nuclei 63Cu and 53Cr in ferromagnetic CuCr2S4:Sb have been investigated at the temperature T=77 K. The experimental results were well explained by the developed theory of the time evolutions of the three-pulse echoes. The main assumption of this theory is the assumption that the temporal fluctuations in the electron magnetization lead to the fluctuations in the hyperfine and quadrupole interaction Hamiltonians.
Keywords: NMR in ferromagnets; Nuclear magnetic relaxation; CuCr2S4

86.
Differences in microstructure and magnetic properties between directly-quenched and optimally-annealed Nd–Fe–B nanocomposite materials Original Research Article
Physica B: Condensed Matter, Volume 405, Issue 2, 15 January 2010, Pages 690-693
Hong-chao Sheng, Xie-rong Zeng, Dong-ju Fu, Fei Deng

87.
In situ synthesis of high density magnetic ferrite spinel (MgFe2O4) compacts using a mixture of conventional raw materials and waste iron oxide Original Research Article
Journal of Alloys and Compounds, Volume 489, Issue 1, 7 January 2010, Pages 269-274
Y.M.Z. Ahmed, E.M.M. Ewais, Z.I. Zaki

88.
Solid-state nuclear magnetic resonance: A valuable tool to explore organic-inorganic interfaces in silica-based hybrid materials Original Research Article
Comptes Rendus Chimie, Volume 13, Issues 1-2, January-February 2010, Pages 58-68
Florence Babonneau, Niki Baccile, Guillaume Laurent, Jocelyne Maquet, Thierry Azaïs, Christel Gervais, Christian Bonhomme

89.
New ramsdellites LiTi2−yVyO4 (0≤y≤1): Synthesis, structure, magnetic properties and electrochemical performances as electrode materials for lithium batteries Original Research Article
Journal of Solid State Chemistry, Volume 183, Issue 1, January 2010, Pages 20-26
Alois Kuhn, María Martín, Flaviano García-Alvarado
Abstract
The new ramsdellite series LiTi2−yVyO4 (0≤y≤1) has been prepared by conventional solid state chemistry techniques and was characterized by X-ray powder diffraction and electron diffraction. To our knowledge, this is the first report on ramsdellites containing vanadium. The magnetic behaviour of these ramsdellites is strongly influenced by its vanadium content. In this sense, LiTi2O4 (y=0) exhibits metallic-like temperature independent paramagnetism, but d electrons tend to localize with increasing V content. LiTiVO4, though also paramagnetic, follows then the Curie–Weiss law. The crossover from delocalized to localized electrons is observed between compositions y=0.6 and 0.8. For y≥0.8 the magnetic results evidence an isovalent substitution mechanism of trivalent Ti by V. The electrochemical lithium intercalation and deintercalation chemistry of LiTi2−yVyO4 is grouped into two different operating voltage regions. Reversible lithium deintercalation of vanadium-substituted ramsdellite titanates LiTi2−yVyO4 in the high voltage range 2–3 V vs. Li occurs in two main steps, one at about 2 V and the other at about 3 V. The 3 V process capacity increases with the vanadium content, while the 2 V capacity decreases at the same time. The vanadium to titanium substitution rate in LiTi2O4 was found to be beneficial to the specific energy in as much as a 50% increase (1 V) of the working voltage is observed. On the other hand, reversible lithium intercalation in vanadium-substituted ramsdellite titanates LiTi2−yVyO4 in the low voltage range 1–2 V vs. Li occurs in one main single step, in which the capacity is not affected by the vanadium content, although vanadium-doping produces an improved capacity retention with an excellent cycling behaviour observed for y≤0.6.

90.
Composite electromagnetic wave absorber made of soft magnetic material and polystyrene resin and control of permeability and permittivity Original Research Article
Journal of the European Ceramic Society, Volume 30, Issue 2, January 2010, Pages 347-353
Kenji Sakai, Norizumi Asano, Yoichi Wada, Shinzo Yoshikado

91.
Twin boundary nucleation and motion in Ni–Mn–Ga magnetic shape memory material with a low twinning stress Original Research Article
Scripta Materialia, Volume 62, Issue 1, January 2010, Pages 9-12
Ilkka Aaltio, Outi Söderberg, Yanling Ge, Simo-Pekka Hannula

92.
Contemporary Applications and Limitations of Magnetic Resonance Imaging Contrast Materials Review Article
The Journal of Urology, Volume 183, Issue 1, January 2010, Pages 27-33
Ricardo A. Natalin, Martin R. Prince, Marc E. Grossman, David Silvers, Jaime Landman

93.
Nanocrystals magnetic contribution to FINEMET-type soft magnetic materials with Ge addition Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 21, November 2009, Pages 3640-3645
D. Muraca, J. Silveyra, M. Pagnola, V. Cremaschi
Abstract
Over the last years several works have been published in which magnetic and structural properties of soft magnetic nanocrystalline alloys were reported. Among these, there are a series of articles where the nanocrystals composition of FINEMET-type alloys with Ge addition was obtained by Mössbauer spectroscopy (MS) and X-ray diffraction (XRD). By considering a linear relationship between the magnetic moments of the nanocrystals and the composition of various elements in these crystallites, the magnetic moment of the nanocrystals was calculated. This paper reviews results obtained by different authors since 1980 and they are compared with ours. In turn, we revised some elements not previously considered for the calculus of the nanocrystals composition that allowed us to obtain the magnetic moment of the crystallites in the alloy. In particular, we analyzed FINEMET-type alloys with replacement of B for Ge: Fe73.5Si13.5Ge2B7Nb3Cu1 and Fe73.5Si13.5Ge4B5Nb3Cu1. The nanocrystalline structure was obtained by isothermal annealing of melt-spun ribbons at 823 K for 1 h. From MS and XRD we obtained the atomic composition of the nanocrystals in the magnetic material. The magnetic contribution of the nanocrystals to the alloy was calculated using a linear model and the results were compared with experimental measurements of the samples.
Keywords: Nanocrystalline material; Magnetic structure; FINEMET ribbon; Melt spinning; Macroscopic and atomistic magnetization analysis

94.
Porous manganese-based magnetocaloric material for magnetic refrigeration at room temperature Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 14, July 2008, Pages e189-e192
J.A. Lozano, M.P. Kostow, E. Brück, J.C. de Lima, A.T. Prata, P.A.P. Wendhausen
Abstract
The powder metallurgy technique has been exploited as a means to prepare porous magnetocaloric materials. The alloy Mn1.1Fe0.9P0.46As0.54 was previously synthesized by mechanical alloying followed by a solid-state reaction for crystallization and homogenization. Subsequently, the alloy was comminuted and sintered at 1298 K. The obtained sintered product is aimed to be tested in a magnetic regenerator of a prototype machine.
Keywords: Magnetocaloric material; Manganese-based compound; Porous material; Magnetic refrigeration

95.
Modern microwave magnetic materials: Recent advances and trends Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 14, July 2009, Pages 2033-2034
Olivier Acher
Abstract
In recent years, a large variety of microwave magnetic materials has been developed, with different compositions, shapes, and fabrication processes. The physics of the dynamic magnetic responses of these materials is very rich, due to the interplay between the intrinsic magnetic properties of the materials, the domain structure, and dynamic shape effects. These materials are associated to a variety of applications, some of them well-established, for direct interaction with rf waves; others corresponding to etablished uses of magnetic materials, but at higher speeds or higher frequencies; and some in association with hot topics in the magnetic or rf communities including metamaterials, nanoscale structures, and nonlinear devices.
Keywords: Magnetic material; Microwave property; Magnetic permeability; Ferromagnetic resonance

96.
Computational nano-materials design for high-TC ferromagnetism in wide-gap magnetic semiconductors Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 310, Issue 2, Part 3, March 2007, Pages 2070-2077
H. Katayama-Yoshida, K. Sato, T. Fukushima, M. Toyoda, H. Kizaki, V.A. Dinh, P.H. Dederichs
Abstract
We propose materials design of high-TC wide band-gap dilute magnetic semiconductors (DMSs) based on first-principles calculations by using the Korringa–Kohn–Rostoker coherent potential approximation (KKR-CPA) method. First, we discuss a unified physical picture of ferromagnetism in II–VI and III–V DMSs and show that DMS family is categorized into two groups depending on the electronic structure. One is the system where Zener's double exchange mechanism dominates in the ferromagnetic interaction, and in the other systems Zener's p–d exchange mechanism dominates. Next, we develop an accurate method for TC calculation for the DMSs and show that the mean field approximation completely fails to predict Curie temperature of DMS in particular for wide-gap DMS where the exchange interaction is short-ranged. The calculated TC of homogeneous DMSs by using the present method agrees very well with available experimental values. For more realistic material design, we simulate spinodal nano-decomposition by applying the Monte Carlo method to the Ising model with ab initio chemical pair interactions between magnetic impurities in DMS. It is found that by controlling the dimensionality of the decomposition various characteristic phases occur in DMS such as 3D Dairiseki-phase and 1D Konbu-phase, and it is suggested that super-paramagnetic blocking phenomena should be important to understand the magnetism of wide-gap DMS. Based on the present simulations for spinodal nano-decomposition, we propose a new crystal growth method of positioning by seeding and shape controlling method in 100 Tera-bit density of nano-magnets in the semiconductor matrix with high-TC (or high-TB).
Keywords: First-principles calculation; Dilute magnetic semiconductor; Ferromagnetism; Computational nano-material design; Curie temperature; Double exchange; p–d Exchange; Super-exchange; Spinodal decomposition; KKR-CPA; SIC-LDA; Monte Carlo simulation

97.
Symmetric magnetic tunnel junctions with amorphous soft magnetic materials as electrodes Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 20, October 2008, Pages e944-e948
Horia Chiriac, Maria Urse, Marian Grigoras
Abstract
Results concerning the influence of the additions of Ni and Ni–Si on the TMR response, saturating magnetic field and thermal stability of symmetric FeMn/FM/Al2O3/FM/FeMn MTJs, with FM=(Fe0.58Co0.25B0.17)100−xMx (M=Ni, Ni–Si), are presented. The magnetoresistance ratio for the symmetric
Si/SiO2/Ta(5)/Ni80Fe20(5)/Fe50Mn50(8)/FeCoBNiSi(3.5)/Al2O3(1)/FeCoBNiSi(5)/Fe50Mn50(8)/T
(5) MTJ structure was changed with about 9% in 20 G magnetic field, leading to a sensitivity of about 0.45%/G. This structure exhibits a field window of about 10 G and low values for the tunneling resistance of about 120 Ω and the thermal coefficient of resistance of about +60 ppm/°C.
Keywords: Tunneling magnetic junction; Symmetric spin valve; Multilayer thin film; Soft magnetic material; Magnetoresistive property

98.
Hydrogen induced structural and magnetic transformations in magnetic regenerator materials ErNin (n=1, 2) and HoCu2 Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 311, Issue 2, April 2007, Pages 697-701
Dong Wang, Yanli Li, Yi Long, Rongchang Ye, Yongqin Chang, Farong Wan
Abstract
The effect of hydrogenation on the structures and magnetic properties of magnetic regenerators HoCu2 (CeCu2-type), ErNi2 (MgCu2-type) and ErNi (FeB-type) has been investigated. All these compounds can form crystalline hydrides which remain in the structure of the original compound. In the case of ErNi2, hydrogenation induces volume expansion up to 13% compared with the parent compound. The magnetic moment and the Curie temperature of the crystalline hydrides decreases as the hydrogen content increases. In the case of ErNi and HoCu2, there is a little change in the lattice parameters and magnetic properties of the crystalline hydrides compared with original compounds. Amorphous hydrides are also observed after the hydrogenation of ErNi2 and HoCu2 compounds.
Keywords: Hydrogen; Structure; Magnetic properties; Regenerator material

99.
Preparation of hard magnetic materials in thin film form Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 14, July 2008, Pages 1966-1971
F. Pigazo, F.J. Palomares, F. Cebollada, J.M. González
Abstract
We report on the preparation, by means of pulsed laser ablation deposition, of trilayers of nominal composition Cr/SmCo5/Cr//Si with thicknesses in the order of 250/240/125 nm, respectively. According to the results of the structural, chemical and magnetic characterizations performed in our as-deposited samples, the Sm–Co layer was structurally amorphous, exhibited abrupt compositional interfaces with the capping and buffering layers, and coercivities of a few hundreds of Oe. Magnetic hardness was developed upon submitting the samples to current anneals under vacuum at temperatures in the range of 540–670 °C. The hardening process was followed in detail by correlating the phase distribution, the nature of the interlayer atomic diffusion processes, the occurrence of textures and the temperature dependence of the coercive force. From our results we conclude about (i) the occurrence of a large degree of Co diffusion/segregation, which results in the detection, from the diffraction and magnetometric results, of the presence of CoCr alloys in the treated samples, and (ii) the close correlation, evidenced from the fits of the temperature dependence of the coercive force to the micromagnetic model, between the coercivity optimization and the crystallinity enhancement of the SmCo5 grains.
Keywords: Hard magnetic material; Thin film; Coercivity

100.
High-frequency nanostructured magnetic materials for integrated inductors Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 20, October 2008, Pages 2509-2512
Paul McCloskey, Brice Jamieson, Terence O’Donnell, Donald Gardner, Michael A. Morris, Saibal Roy
Abstract
Electroplating is compatible with the deposition of relatively thick layers i.e. several μm to 10s- of μm. However eddy current losses mean that thick layers will have an inferior frequency response. We have used a low content phosphorous bath together with pulse reverse plating to generate Co-rich and Co-deficient multi-nanolayers of CoP having improved saturation magnetisation and a better frequency response. The plating parameters have been optimised in order to produce a material with low loss, and a high permeability of around 700 retained up to 103 MHz for a sample with a thickness of 1.7 μm and a resistivity of 136 μΩ cm.
Keywords: Integrated inductor; Multi-nanolayer; High-frequency soft magnetic material

101.
New possibilities of composite materials application—Materials of specific magnetic properties Original Research Article
Journal of Materials Processing Technology, Volume 191, Issues 1-3, 1 August 2007, Pages 352-355
L.A. Dobrzański, M. Drak, B. Ziębowicz
Abstract
This paper presents the material and technological solution which makes it possible obtaining of soft and hard magnetic composite materials: nanocrystalline material–polymer. For fabrication of composite materials the following powders were used: soft magnetic material (Fe73.5Cu1Nb3Si13.5B9) and hard magnetic material (Nd14.8Fe76Co4.95B4.25). Polymer was used as the matrix (2.5 wt.%). Advanced composite materials were compacted by the one-sided uniaxial pressing. The complex relationships among the manufacturing technology of these materials, their microstructure, as well as their mechanical and physical properties were evaluated. Materialographic examination of powders morphology and the structure of composite materials were made. Composite materials show regular distribution of magnetic powder in polymer matrix. Examination of mechanical properties shows that these materials have satisfactory compression strength. Composite materials show lower magnetic properties in comparison with magnetic powder but their geometrical form allows extending their applications. The paper shows also the possibilities of these magnetic materials application. The advantage of the bonded composite materials is their simple technology, possibility of forming their properties, lowering manufacturing costs because of no costly finishing and lowering of material losses resulting from the possibility of forming any shape. The manufacturing of composite materials greatly expand the applicable possibilities of nanocrystalline powders of magnetically hard and soft materials.
Keywords: Magnetic materials; Nd–Fe–B; FINEMET; Composite materials

102.
Advances in magnetic materials and their impact on electric machine design Original Research Article
Journal of Materials Processing Technology, Volume 181, Issues 1-3, 1 January 2007, Pages 148-152
G.K. Kalokiris, A.G. Kladas, I.K. Hatzilau, S. Cofinas, I.K. Gyparis
Abstract
The paper presents machine design considerations introduced by exploiting new magnetic material characteristics. The materials considered are amorphous alloy ribbons as well as Neodymium alloy permanent magnets involving very low eddy current losses. Such materials enable electric machine operation at higher frequencies compared with the standard iron laminations used in the traditional magnetic circuit construction and provide better efficiency.
Keywords: Magnetic materials; Permanent magnets; Iron losses

103.
Low temperature sintering and magnetic properties of garnet microwave magnetic materials Original Research Article
Materials Chemistry and Physics, Volume 105, Issues 2-3, 15 October 2007, Pages 408-413
Chien-Yie Tsay, Chung-Kwei Lin, Hua-Chi Cheng, Kuo-Shung Liu, I.-Nan Lin
Abstract
This study investigated the low temperature sintering for microwave magnetic materials [Bi-incorporated calcium vanadium garnets (Bi-CVG), (Bi0.75Ca1.2Y1.05)(V0.6Fe4.4)O12]. Sintering behavior and magnetic properties of Bi-CVG materials prepared from ultrafine-sized powders were compared with those of materials prepared from micron-sized powders. The activation energy for densification (Ed), derived from temperature and time dependence of materials’ density, is markedly reduced by using ultrafine-sized powders as starting materials, i.e., (Ed)ultra = 7.04 kJ mole−1 and (Ed)micron = 39.5 kJ mole−1 for ultrafine and micron powder sintered samples, respectively. The activation energy for densification is further reduced to 4.59 kJ mole−1 by using microwave sintering process with ultrafine powders. Remnant magnetization (Br) of the Bi-CVG materials is similar for samples possessing the same high density, regardless of the microstructures. Conversely, the coercive field (Hc) of the materials is larger for samples containing fine grains and vice versa. While the low frequency magnetic properties of the Bi-CVG materials are microstructure-dependent, the microwave magnetic properties of the materials are not.
Keywords: Bi-CVG; Low temperature sintering; Microwave magnetic materials

104.
Porous soft magnetic material: The maghemite microsphere with hierarchical nanoarchitecture and its application in water purification Original Research Article
Materials Research Bulletin, Volume 44, Issue 12, December 2009, Pages 2233-2239
Xin Liang, Baojuan Xi, Shenglin Xiong, Yongchun Zhu, Fei Xue, Yitai Qian
Abstract
Porous soft magnetic material is a member of soft magnetic material family having large surface area. This kind of material has vast potential in the surface-related applications. In this paper, a kind of maghemite (γ-Fe2O3) with large surface area, 82.7 m2/g, specifically, was obtained by the solvothermal method and subsequent calcining process. As shown in the test results, the maghemite microsphere has no magnetic memory in the magnetic field since the residual magnetization is 0.7 emu/g. In the waste water treatment process, Rhodamine B, a model organic pollutant in the water, was removed through the adsorption and desorption cycles by the maghemite microspheres. The maghemite microspheres in the water can be recycled easily by a magnetic separation procedure and regenerated in ethanol at room temperature.
Keywords: A. Magnetic materials; A. Nanostructures; B. Chemical synthesis; C. Raman spectroscopy; D. Surface properties

105.
Low damage smoothing of magnetic material films using a gas cluster ion beam Original Research Article
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Volume 257, Issues 1-2, April 2007, Pages 677-682
S. Kakuta, S. Sasaki, T. Hirano, K. Ueda, T. Seki, S. Ninomiya, M. Hada, J. Matsuo
Abstract
This paper proposes a low damage smoothing process for magnetic materials using a gas cluster ion beam (GCIB). In order to achieve low damage processing, the effect of incident angle was investigated. Depth profiles of major elements constituting the films were measured by secondary ion mass spectroscopy (SIMS). The film structure and the lattice spacing were obtained by X-ray reflectivity (XRR) and grazing incident X-ray diffraction (XRD), respectively. After the GCIB irradiation at an acceleration voltage of 20 kV and incident angle of 80° with simultaneous rotation, a smooth surface of a PtMn film was obtained, with an average roughness of 1.2 nm. A damaged layer thickness of less than 1.5 nm was achieved under these conditions. Using the oblique GCIB irradiation, the PtMn film was etched without any change in the strain profile. Thus, the GCIB could be utilized to obtain surfaces of magnetic devices with extremely shallow damage.
Keywords: Gas cluster ion beam; Magnetic materials; Surface smoothing; Ion irradiation damage

106.
Magnetic properties of nanocomposite Fe-doped SBA-15 magnetic materials Original Research Article
Materials Chemistry and Physics, Volume 112, Issue 1, 15 November 2008, Pages 112-114
H.X. Jin, L. Li, N.J. Chu, Y.P. Liu, L.Y. Wang, Q. Lu, J. Qian, L.N. Sun, Q. Tang, H.L. Ge,
X.Q. Wang
Abstract
Fe-doped SBA-15 magnetic materials was synthesized by pH-adjusting method, and then characterized by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). All results showed that the samples presented ferromagnetism and the magnetism improved with the Fe content. Saturation magnetization and coercivity of the as-prepared Fe-doped SBA-15 samples increased with the calcined temperature up to 850 °C, followed by decreasing. Furthermore, the magnetic properties at lower temperature (measured at 100 K) of the Fe-doped samples was presented. Finally, the type of the intergranular exchange interaction was conformed by plotting Henkel (δM) formulation.
Keywords: Magnetic materials; Sol–gel growth; Microstructure; Magnetic properties

107.
First magnetic materials with sensitivity for the physical quantity “curvature” Original Research Article
Journal of Materials Processing Technology, Volume 181, Issues 1-3, 1 January 2007, Pages 186-189
H. Pfützner, E. Kaniusas, J. Kosel, L. Mehnen, T. Meydan, F. Borza, M. Vázquez, M. Rohn,
A.M. Merlo, B. Marquardt
Abstract
All magnetostrictive types of soft magnetic materials show some weak sensitivity to processes of bending. However, as demonstrated here, a prerequisite for high sensitivity values is that the profile of material exhibits asymmetry with respect to physical characteristics. Specific technological processes yield ultra high sensitivity, a curvature of 1/m causing permeability changes of more than 50%.
Keywords: Soft magnetic materials; Compound materials; Magneto-elastic effect; Sensors; Curvature

108.
Magnetic susceptibility and electrical conductivity of metallic dental materials and their impact on MR imaging artifacts Original Research Article
Dental Materials, Volume 24, Issue 6, June 2008, Pages 715-723
Jana Starčuková, Zenon Starčuk Jr., Hana Hubálková, Igor Linetskiy

109.
Determination of 3D magnetic reluctivity tensor of soft magnetic composite material Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 312, Issue 2, May 2007, Pages 458-463
YouGuang Guo, Jian Guo Zhu, Zhi Wei Lin, Jin Jiang Zhong, Hai Yan Lu, Shuhong Wang
Abstract
Soft magnetic composite (SMC) materials are especially suitable for construction of electrical machines with complex structures and three-dimensional (3D) magnetic fluxes. In the design and optimization of such 3D flux machines, the 3D vector magnetic properties of magnetic materials should be properly determined, modeled, and applied for accurate calculation of the magnetic field distribution, parameters, and performance. This paper presents the measurement of 3D vector magnetic properties and determination of 3D reluctivity tensor of SMC. The reluctivity tensor is a key factor for accurate numerical analysis of magnetic field in a 3D flux SMC motor.
Keywords: Soft magnetic composite (SMC); 3D vector magnetic property; Magnetic reluctivity tensor; Numerical analysis of magnetic fields

110.
Connection between microstructure and magnetic properties of soft magnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 20, October 2008, Pages
2436-2442
G. Bertotti
Abstract
The magnetic behavior of soft magnetic materials is discussed with some emphasis on the connection between macroscopic properties and underlying micromagnetic energy aspects. It is shown that important conceptual gaps still exist in the interpretation of macroscopic magnetic properties in terms of the micromagnetic formulation. Different aspects of hysteresis modeling, power loss prediction and magnetic non-destructive evaluation are discussed in this perspective.
Keywords: Micromagnetics; Magnetic hysteresis; Hysteresis model; Power loss; Non-destructive evaluation

111.
High-frequency response of nanostructured magnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 14, July 2009, Pages 2074
2081
N. Vukadinovic

112.
On the determination of the magnetic entropy change in materials with first-order transitions Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 21, November 2009, Pages 3559-3566
L. Caron, Z.Q. Ou, T.T. Nguyen, D.T. Cam Thanh, O. Tegus, E. Brück

113.
Active magnetic regenerator performance enhancement using passive magnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 7, April 2008, Pages 1357-1363
A. Rowe, A. Tura

114.
Three-dimensional magnetic properties of soft magnetic composite materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 312, Issue 1, May 2007, Pages 158-163
Z.W. Lin, J.G. Zhu

115.
Field dependence of the magnetic entropy change in typical materials with a second-order phase transition Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 319, Issues 1-2, December 2007, Pages 56-59
Qiao-yan Dong, Hong-wei Zhang, Jue-lian Shen, Ji-rong Sun, Bao-gen Shen

116.
Oriented magnetic material in head and antennae of Solenopsis interrupta ant Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issue 14, July 2008, Pages e204-e206
L.G. Abraçado, D.M.S. Esquivel, E. Wajnberg

117.
Research on preparing compact bulk nanocomposite Nd2Fe14B/α-Fe magnetic materials by hot extrusion Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 312, Issue 1, May 2007, Pages 220-223
Ying Wang, Erde Wang

118.
Glass formation and magnetic properties of Fe–C–Si–B–P–(Cr–Al–Co) bulk metallic glasses fabricated using industrial raw materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 18, September 2009, Pages 2833-2837
.X. Li, S.L. Wang, S. Yi, Z.B. Jiao, Y. Wu, Z.P. Lu

119.
Precise measurements of radio-frequency magnetic susceptibility in ferromagnetic and antiferromagnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 320, Issues 3-4, February 2008, Pages 354-363
M.D. Vannette, A.S. Sefat, S. Jia, S.A. Law, G. Lapertot, S.L. Bud’ko, P.C. Canfield, J.
Schmalian, R. Prozorov

120.
Magnetic and optical properties of Mn-implanted Si material Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 311, Issue 2, April 2007, Pages 693-696
I.T. Yoon, C.J. Park, T.W. Kang

121.
Magnetic-field behavior of heterogeneous magnetic materials Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 321, Issue 7, April 2009, Pages 865-867
E.E. Shalygina, G.V. Maximova, M.A. Komarova, V.A. Melnikov, A.N. Shalygin, V.V.
Molokanov

122.
Synthesis and magnetic properties of Co1−xZnxFe2O4+γ nanoparticles as materials for magnetic fluid hyperthermia Original Research Article
Journal of Magnetism and Magnetic Materials, Volume 322, Issue 16, August 2010, Pages 2386-2389
M. Veverka, P. Veverka, Z. Jirák, O. Kaman, K. Knížek, M. Maryško, E. Pollert, K. Závěta

123.
New complex magnetic materials for an application in Ericsson refrigerator
Solid State Communications, Volume 149, Issues 25-26, July 2009, Pages 969-972
S. Othmani, R. Blel, M. Bejar, M. Sajieddine, E. Dhahri, E.K. Hlil

124.
Impact of molecule-based magnetic materials: A critical outlook
Solid State Sciences, Volume 11, Issue 5, May 2009, Pages 970-971
Eva Rentschler, Marco Affronte, Carlo Massobrio, Pierre Rabu, Jaume Veciana

125.
Growth of novel-diluted magnetic semiconducting material Ge1−xMnx and X-ray characterization by the maximum entropy method (MEM) and pair distribution function (PDF) Original Research Article
Journal of Crystal Growth, Volume 311, Issue 4, 1 February 2009, Pages 1110-1116
K.S. Syed Ali, R. Saravanan, S. Israel

126.
Hard magnetic composite materials Nd-Fe-B with additions of iron and X2CrNiMo-17-12-2 steel Original Research Article
Journal of Alloys and Compounds, Volume 449, Issues 1-2, 31 January 2008, Pages 88-92
L.A. Dobrzański, M. Drak

127.
Product change of molecule-magnetic material synthesis induced by magnetic field in hydrothermal system Original Research Article
Journal of Crystal Growth, Volume 329, Issue 1, 15 August 2011, Pages 82-85
Helin Niu, Jitang Chen, Qiong Niu, Yuanhao Gao, Jiming Song, Changjie Mao, Shengyi Zhang,
Qianwang Chen

128.
Low damage smoothing of magnetic materials using off-normal gas cluster ion beam irradiation Original Research Article
Surface and Coatings Technology, Volume 201, Issues 19-20, 5 August 2007, Pages 8632-8636
S. Kakuta, S. Sasaki, K. Furusawa, T. Seki, T. Aoki, J. Matsuo

129.
Some variational principles in elastic dielectric and elastic magnetic materials Original Research Article
European Journal of Mechanics - A/Solids, Volume 27, Issue 3, May-June 2008, Pages 504-514
Zhen-Bang Kuang

130.
Nanocrystalline magnetic materials versus ferrites in power electronics Original Research Article
Procedia Earth and Planetary Science, Volume 1, Issue 1, September 2009, Pages 1357-1361
Georgi T. Nikolov, Vencislav C. Valchev

131.
Application of derivatized magnetic materials to the separation and the preconcentration of pollutants in water samples Review Article
TrAC Trends in Analytical Chemistry, Volume 30, Issue 7, July-August 2011, Pages 1095-1108
Ligang Chen, Ting Wang, Jia Tong

132.
Simulation of the propagation effects in the HF-EPR spectra of non-diluted magnetic materials Inorganica Chimica Acta, Volume 361, Issues 14-15, 1 October 2008, Pages 4164
4166
Denise Friselli, Carlo-Andrea Massa, Massimo Martinelli, Luca Pardi, Irene Ricci

133.
Magnetic field-induced formation of molecule-based magnetic material [Co1.5(N3)(OH)(L)]n with antiferromagnetic coupling Original Research Article
Journal of Crystal Growth, Volume 310, Issue 16, 1 August 2008, Pages 3788-3791
Ju-Zhou Zhang, Qian-Wang Chen, Nan Tao

134.
Magnetic hysteresis loops in molecular-based magnetic materials AFeIIFeIII(C2O4)3 Original Research Article
Physica A: Statistical Mechanics and its Applications, Volume 389, Issue 11, 1 June 2010, Pages 2227-2233
Wei Jiang, Veng-cheong Lo, Bao-Dong Bai, Jun Yang



Magnetic Materials / Nanomagnetic
Up. DR. Setyo Purwanto-BATAN