15 May 2015, Volume 46 Issue 09
    

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    研究 开发
  • duan-lian tang;Xiao-Juan Li
    . 2015, 46(09): 1-0.
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    Magnetic Bi2WO6–NiFe2O4 visible-light photocatalyst was successfully synthesized by a simple hydrothermal route. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), UV-Visible diffuse reflectance spectra (UV-Vis DRS), scanning electron microscopy (SEM) and magnetic property measurement system(MPMS). The photocatalytic activities of the photocatalyst were evaluated by degradation of Rhodamine B (RhB) in aqueous solution under visible light at different pH value. The results demonstrated that 98% of RhB could be removed from aqueous solution by Bi2WO6–NiFe2O4 photocatalyst after 2 h irradiation at pH = 5. Bi2WO6-NiFe2O4 photocatalyst can be easily separated from solution using an external magnetic field.
  • ;
    . 2015, 46(09): 2-0.
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    An amphiphilic block copolymer based on poly(styrene-co-maleic anhydride)-b-poly(single-methoxypoly(ethylene glycol) methyl acrylate) (PSMA-b-PMAPEG), was synthesized by reversible addition fragmentation chain transfer radical (RAFT) polymerization, and was further modified by p-aminoazobenzene to form photo-responsive block copolymer P(St-al-Ma/azo-MaIM)-b-PMAPEG. The block copolymer was characterized by Fourier transform infrared spectroscopy(FT-IR), 1H nuclear magnetic resonance (1H NMR), and gel permeation chromatography (GPC). Nanosized micelles were formed by self-assembly when the P(SMA/azo-MaIM)-b-P(MAPEG) was dissolved in water solution. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) measurements showed that the micelles were regularly spherical in shape with an average diameter of ~100 nm. The photo-responsive behavior of the copolymer was studied by UV-Vis spectroscopy, DLS and scanning electron microscopy (SEM). The UV-Vis spectroscopy indicates that the absorption peak at 360 nm decreased and the peak at 450 nm increased with increasing the irradiation time of 365 nm UV light, and the corresponding absorption peak recovered when the solution continued to be irradiated using 420 nm visible light. The DLS measurements indicated that the size of the micelles increased from ~100 nm to ~300 nm when they were exposed under 365 nm light, and the micelles’ size decreased from ~300 nm to ~100 nm when the irradiation was changed to 420 nm visible light, and these results were confirmed by SEM measurements. The size change of the micelles under the irradiation with different wavelength was caused by the isomerization of azobenzene which changed from trans-form to cis-form by UV irradiation of 365 nm and recovered to trans-form by visible light irradiation of 420 nm.
  • . 2015, 46(09): 3-0.
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  • ;;;;
    . 2015, 46(09): 5-0.
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    In this paper, Mn-doped flower-like ZnO microstructures with various doping concentration (0 mol%, 0.25mol%, 0.5mol% and 1.0mol %) were fabricated using liquid phase deposition at room temperature. The phases and morphologies of Mn-doped flower-like ZnO microstructures were characterized by XRD, SEM and TEM. The photocatalytic performances of Mn-doped flower-like ZnO microstructures with various doping concentration were studied using methyl orange as the stimulant pollutant. The measured results indicated that Zn2+ maybe replaced by Mn2+ in the lattice of ZnO or exist on the surface of ZnO nanoplates as Mn3O4. Moreover, the experimental results prove that Mn-doped ZnO microstructures can improve the performance of photocatalytic degradation. The optimization of Mn content is 0.25mol%, and degradation rate for methyl orange can reach to 88.7%.
  • ;
    . 2015, 46(09): 6-0.
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    Pyrocarbon for prosthetic heart valves that was prepared by quasi-steady-state fluidized bed chemical vapor deposition (FBCVD). The density and the pore structure of pyrocarbon were investigated by densimeter, scanning electron microscope, transmission electron microscope and mercury injection apparatus. Results show that the pore in high density isotropic pyrocarbon deposited at low temperature is mainly composed of the larger pores of about 0.83 μm and the medium pores of about 62 nm between particles in sphere-like structure and the micro-pores derived of entangled structure in spherical particles. The micro-pores from entangled structure can reduce the local density of pyrocarbon and the amount of spherical particles in pyrocarbon could affect the density of pyrocarbon
  • Xiao-Li ZHANGNai-Fei WANG;;;Shi-Xue ZHOU
    . 2015, 46(09): 7-0.
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    The material was prepared by mechanical milling of magnesium under hydrogen atmosphere for 3 h with bituminous coal and crystallitic carbon which was prepared from anthracite coal by demineralization and carbonization, as milling aid. The experiment of hydrogen desorption was operated under the isothermal condition by volumetric method. According to Arrhenius equation and the data of hydrogen desorption, the activation energy is 94.33 kJ/mol. TPD curves of the material under variable condition was measured and the activation energy was calculated by Kissinger method and Sharp method. The activation energy of hydrogen desorption is 105.87 kJ/mol calculated by Kissinger method according to TPD curves and it is 108.33 kJ/mol, 98.70 kJ/mol and 113.19 kJ/mol at the heating rate 5℃/min, 10℃/min and 15℃/min, respectively. Both of the two methods can be used for the calculation of activation energy and the results are different because of the equations, theories of them and the data they employed are different.
  • Ya-Di TENGXiao-Long SUN;;Yong-Gang SHENG;
    . 2015, 46(09): 8-0.
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    A series of Vinylhydromethylpolysilazanes(PVHMS135-170) were prepared from dichlorohydromethylsilane and dichloromethylvinylsilane by ammonolysis polycondensation and thermopolymerization. The vinylhydromethyl polysilazanes have number-average molecular weights (Mn) of 2.9×103~1.9×105 . Per concentration viscosity (ηred) of the polymers are 0.06~0.49. The structures of the polysilazanes were characterized by FTIR and 1H-NMR. The polysilazanes are amorphous and soluble in common organic solvents such as hexane, toluene, ethyl acetate, dichloromethane, N,N-dimethylformamide and so on. The thermal properties of the polysilazanes were analyzed by TGA. It was found that the residual percent of the series of the PVHMS enhanced gradually after pyrolysis in nitrogen at 700℃ along with the increasing of molecular weights, could almost reach 72.58%. Moreover, the analysis results revealed that ceramic yield of the polysilazanes rose up as increasing of molecular weights
  • ;
    . 2015, 46(09): 9-0.
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    It is investigated that the growth process of TiO2 nanocrystalline under the hydrothermal condition with the presence of malonic acid, butyl alcohol or ethylenediamine. The XRD results show that the products are anatase and the images of TEM and HRTEM show that the construction feather of TiO2 nanoparticles is different at the different stage. Furthermore, three nanoparticle growth models, such as Orientation attachment (OA), Frenkel shrinking (SH) and Ostwald ripening (OR), were employed to fit nanoparticle growth data in order to elucidate growth mechanisms operating during hydrothermal aging. It is discovered that a unique three-stage hydrothermal growth of anatase nanoparticles is presented in malonic acid and ethylenediamine: OA, SH, and OR. The crystalline size under ethylenediamine is bigger than that under malonic acid. The Ostwald ripening mechanism is dominant under butyl alcohol. According to the data, the different growths depend on the detailed interplay between bulk solution pH and surface chemistry.
  • Ke Zhang
    . 2015, 46(09): 10-0.
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    We report an optical polarized material and device as a new kind of optical polarizer. The device consists of periodically distributed ellipsoid silver nanorods inside the transparent Ag-doped glass. Mie scattering theory and dipole theory can be well used to explain the physics interrelationships. The output shows strong polarization and high optical extinction ratio transmission properties through the glass polarizer. In our calculations, the polarization transmission is more than 80% with extinction ration more than 20dB within the whole infrared wavelength 700nm-1100nm. Especially in a bandwidth of 100nm from 740nm to 840nm, the transmission is over 90% with extinction ratio over 50dB. This approach is important for new application and detection in laser optics and functional materials.
  • . 2015, 46(09): 11-0.
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    study to the acoustic wave band gap characteristics of two-dimensional phononic crystals microcavity with cross-shaped structure with local resonant using finite element method. At the same time, the corresponding displacement eigenmodes of the band edges of lowest band gap and the transmission spectrum are calculated. The results proved that phononic crystals with microcavity structure appeared complete band gaps in low frequency range. The eignfrequency of the lower edge of the first gap is lower than no microcavity structure. However, for no microcavity structure type of quadrilateral phononic crystal plate, the second band gap is disappeared and the frequency range of the first band gap is relatively narrow. The main reason for local resonant and lead to appear low frequency band gaps is microcavity structure. This study provides a good support for engineering application such as low frequency vibration attenuation and noise control.
  • ;wangluming
    . 2015, 46(09): 12-0.
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    using the anionic surfactant and the foam stabilizer to compound modified with Protein-concrete foaming agent.the anionic surfactant include α-olefin sulfonate (AOS), sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (LAS),the foam stabilizer include Polyether silicone emulsion (MPS), dodecyl alcohol and hydroxyethyl cellulose.The results show that the foam stability of proteins foaming is much better than the anionic surfactant, however the foam volume is inadequate. The three kinds anionic surfactants can all be used to improve the foam?property of Protein-concrete foaming agent, the appropriate dosage is 0.9-1.0g/L. Polyether silicone resin emulsion(MPS)and dodecyl alcohol all can improve the foam?property of composite system but they can not be doped together. Hydroxyethyl cellulose is a high performance foam stabilizer, the right dosage at 1.0g/L or less.
  • ;;
    . 2015, 46(09): 13-0.
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    Using the traditional process of preparation of TiO2 and ZnO doped WO3 ceramics, using X-ray diffraction (XRD) and scanning electron microscopy (sem) analysis of the microstructure, and in 273 K to 973 K for thermoelectric performance measurements, found that grain size has a little change,and the generation of a second phase. All of the different concentrations of samples within the measuring range are negative, that is still the n type oxides thermoelectric materials. Experiments show that the sample with 0.5 mol% doping concentration has the largest power factor,which is 0.052μWm-1K-2 at 973 k.
  • . 2015, 46(09): 14-0.
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    In this study, the native collagens (NC) were extracted from skin of grass carp, which were typeⅠcollagen with intact triple helix structure proved by the DSC and circular dichroism analysis. Low thermal denaturation (LD), high thermal denaturation (HD) and complete thermal denaturation(CD)collagen samples were obtained by heat treatment with NC under different conditions, and the degrees of thermal denaturation of those collagen samples were 16.9%、57.9 and 100% according to the results of DSC determination. On this basis, the changes in the collagen structure and the properties of collagen sponges after this heat treatment were studied. The results show that the onset endothermic temperature (To) is the threshold temperature for the molecule structure and sponges properties stability. When subjected to temperatures above this threshold temperature even in short time, the triple helix structure of collagen would completely or partial unfold. At the same time, the ordering of material structure, the mechanical properties and enzymatic sensitivities of collagen sponges reduced, but the cell proliferation ability enhanced along with the rising of degrees of thermal denaturation of collagen. According to this research, To is the crucial temperature and this temperature should not be exceed during the production and utilization of native collagens.
  • ; ;;
    . 2015, 46(09): 15-0.
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    The objective of this paper is to evaluate some properties of binderless particle board made by various type of bamboo chips and glued by extracted natural activator at different hot pressing temperature. The results reveal that all types of binderless particle board are enforced at internal bond strength with increasing pressing temperature, and maximum one is made by slice chips. In addition, thickness swelling rate of water absorption has improved largely for the board made by slender and pelleted chips accordingly. But the best one is made by slice chips below 190℃ while it becomes to be the worst one when pressing temperature is above 190℃. Among all type of the species, the maximum bending strength and modulus come from binderless particleboard made by slice chips. The failure mode of bending test includes tensile failure of bottom surface and core shear failure while core tensile non-plastic failure is the main failure mode of tensile test of board.
  • ZHU Xiao-jie ZHU;;;;;
    . 2015, 46(09): 16-0.
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    γ-Polyglutamic acid (γ-PGA) could self-assembly into stable colloidal particles in the selective solvent Dimethyl sulfoxide (DMSO)/Ethanol. The characterization of γ-PGA colloidal particles were studied by Zeta potential and nano particle size measurements and Atomic force microscope (AFM). The γ-PGA biomedical nanostructured coating on magnesium alloy was prepared by electrodeposition of γ-PGA colloidal particles in ethanol. The characterization of γ-PGA nanostructured coating was conducted by Attenuated Total Reflectance-Fourier Transform Infrared Spectrometer (ATR-FTIR), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Electrochemical measurement. The results showe that the diameter of γ-PGA colloidal particles is 221 nm. The corrosion rate of magnesium alloy coated with γ-PGA nanostructured coating is reduced and further chemical cross-linking of the coating by ethylenediamine is also contribution to the corrosion resistance of the substrate.
  • . 2015, 46(09): 17-0.
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    To meet the requirement of integrative mechanical and functional properties of shielding materials, a type of Fe-Ni-B alloy coating was designed and produced on typical 321 stainless steel substrate (1Cr18Ni9Ti) by air-plasma spraying technique. This sort of coating has normally been used as protection against neutrons and γ rays emanating from fission reactors. The design and preparation of the Fe-Ni-B coating / SS substrate laminated composite, and the relative key parameters and details had been described. The paper primarily investigated the radiation shielding abilities against neutron and gamma rays of the laminated composite, including the effective ability for the slowing down of fast-speed neutrons, the attenuation ability against 60Co and 137Cs γ rays and absorption for 0.4eV below thermal neutrons. The results indicates that the Fe-Ni-B alloy coating / stainless steel laminated composite by optimal APS procedure posses excellent integrative shielding effectiveness against thermal neutron, fast-speed neutron, and γ rays, and has the potential to be applied in nuclear radiation shielding devices.
  • 综述 进展
  • Chunzhi Zhang
    . 2015, 46(09): 18-0.
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    As a new type of filler metal, amorphous alloy has the liquid-like structure, i.e. long-range disorder and short-range order. Such structural feature enables multiple advantages including high strength, hardness, and corrosion resistance et al. Quenched ribbons can also used for narrow-gap welding. The amorphous filler metal shows prospect in fields such as aerospace, military industry, sport equipment, and electronic instrument and so on. In order to illustrate the significance of amorphous filler metal for the development of brazing technology, the research progress in aspects of composition optimization, characterization of filler metals, processes and methods was reviewed. The faced challenges and investigation tendency of amorphous filler metals were also summarized.
  • ;
    . 2015, 46(09): 19-0.
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    Quantum dots (QDs) as a novel fluorescent nano material with excellent performance of optical, electrochemistry and photoluminescence attract extensive research interest in bioanalysis, medical diagnosis, sensors of electrochemistry, deliver drugs and solar battery. Cyclodextrins are well-known molecular hosts capable of including hydrophobic molecules inside the cavities, which also have fine properties of biocompatibility and solubility. The cyclodextrin had significant progressed in many fields such as fluorescent sensors, innoxious organic synthesis and construction of gene delivery. With the modification of cyclodextrin, the quantum dots have many fire-new properties and attract extensive interest in passed years, and researchers acquire a great achievement in the application of biomedicine and analysis of medicine. This review, which follows the classification of selective recognition for bioactive molecules, drug molecules and the other molecules with cyclodextrin-modified quantum dots, summarizes the representative research and applications in these aspects from 2009 to update. Meanwhile, the prospects and research directions of cyclodextrin-modified quantum dots are given based on the analysis of this research filed.
  • ;Na Li ;
    . 2015, 46(09): 20-0.
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    The main method to prepare hydrogen on a large scale is water electrolysis. In order to decrease cathode overpotential for reducing energy consumption,it is of great significance to research new cathode eletrode materials which have high electrocatalytic activity. There are two important factors that can affect the electrocatalytic activity of the hydrogen-evolution materials: energy factors and geometry factors. The progress of research on the electrode materials for hydrogen evolution in water electrolysis is reviewed and its future trends are expected.
  • ; ;;;;
    . 2015, 46(09): 21-0.
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    Abstract: Carbon quantum dots (CQDs, C-dots or CDs), a new type of carbon materials, less than 10 nm in size, have a lot of excellent performance, such as superior solubility in water, chemical inertness, low toxicity, easy functionalization, resistance to photobleaching and good photostability, having attracted widespread attention as a rising star in nanocarbon family in recent years. Since the phenomenon of bright colorful light from carbon quantum dots was reported in 2006, research groups around the world have begun to investigate the carbon quantum dots. CQDs produced from various synthetic strategies find their wide values in more and more fields, especially in biomedicine, optoeletronics, catalysis and sensors. In this review, we describe the recent progress in the field of CQDs, focusing on their synthetic methods, size control, modification strategies, photoelectric properties, luminescent mechanism, and applications in biomedicine, optoelectronics, catalysis and sensor issues.
  • 工艺 技术
  • . 2015, 46(09): 22-0.
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    This paper researched the optimizing technology of the rutile titanium dioxide on ZrO2-Al2O3 both dropwise add coated with orthogonal experiment L9(34) by sol-gel method. Effect of the rutile titanium dioxide ZrO2-Al2O3 coated and coated mechanism were investigated by Nano-ZS, scanning electron microscopy (SEM), transmission electron microscopy(TEM) and energy spectrum(EDS)etc.. The optimum process conditions of the rutile titanium dioxide ZrO2-Al2O3 coated was obtained. Two layers compact and uniform aluminium oxide and zirconium dioxide film on the surface of the rutile titanium dioxide was confirmed. At the same time, the two layers film by the form of chemical bonds combination in the rutile titanium dioxide surface was confirmed.
  • Bo Li
    . 2015, 46(09): 23-0.
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  • ;;;; Rong ZENG
    . 2015, 46(09): 25-0.
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    Abstract: PVA/quaternized chitosan composite hydrogel as artificial dressing was prepared by solution blending method, in which, PVA was served as substrate, quaternized chitosan as antibacterial agent and glycerol as excipients. The combination properties of the composite hydrogel were studied via the rheological test, the antibacterial test, cytotoxic test and animal experiment. The results indicated that PVA/quaternized chitosan hydrogel possessed appropriate viscosity(22~35 Pa?s), showed better adhesion performance when coated onto the skin. The composite hydrogel exhibited excellent inhibition effect to Escherichia coli and Staphylococcus aureus, caused only minimal irritation to skin and excellent cytocompatibility as well. The observations of deep Ⅱ degree burn repair test for Kunming mice revealed that the composite hydrogel was beneficial to healing of wound, formation of scar and shortening the healing time.
  • Jin-Mei DU ;; ;
    . 2015, 46(09): 26-0.
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    Traditional alkali deweighting treatment was applied to polyester fabric first to improve its physical properties. Polyacrylic acid was applied next to increase reactive group sits on polyester fiber. Tetraethylorthosilicate prefer hydrolysis low pH, but has condensation reaction under alkaline conditions. Polyester is stable under mild acid and alkaline. Therefore, polyester fabric was treated with tetraethylorthosilicate under acid solution first and then kept reaction under alkaline condition. Octadecylamine has long alkyl chain, which could help reduce fabric surface energy. After Tetraethylorthosilicate and octadecylamine treatment, fabric is hydrophobic and the static water contact angle on treated polyester fabric is 116°. SEM images of treated fabric has rough surface than untreated one.
  • SONG Xiu Mei ;
    . 2015, 46(09): 27-0.
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    Starting from 4-nitroaniline, the key intermediate 3,5-dibromoaniline was obtained by sequential reactions of bromination, diazotization deamination and nitro-reduction. Then 3,5-dibromoaniline and 3-bromoaniline were reacted with phenol derivatives to give 10 novel D-π-A azobenzene derivatives via azo coupling respectively. The structures of the target compounds were confirmed by NMR, ESI-MS, elemental analysis and X-ray single crystal diffraction. The photochromic property was characterized by UV-Vis spectroscopy, and the reversible cis-trans isomerization speed constants were tested. The results indicate that the target compounds displayed sensitive photochromic response. The isomerization speeds constants ranged from 10-2 to 10-3 s-1. The isomerization speeds mainly depended on molecular steric hindrance.
  • ;;
    . 2015, 46(09): 28-0.
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    The composite ceramic coatings were fabricated on TC4 by micro-arc oxidation adding different ceramic particles(SiC、SiO2) separately into the same electrolyte. The effects of different ceramic particles addition on microstructure、element distribution 、phase composition and wear resistance of ceramic coating were analyzed by SEM、XRD and a MMA-1 model friction and wear tester respectively. The results show the surfaces with ceramic particles are much denser and smoother,and the thickness is also increased.The ceramic particles are successfully embedded in the coatings,while do not occur the phase transition reaction. The SiC particles consist of α-Ti、TiO2and α-SiC、β-SiC. The wear resistance of the coatings can be improved by adding SiC and SiO2 particles.
  • xiao xiao luo;xuan sheng lin;wei qin;Gang Xiao Wen
    . 2015, 46(09): 29-0.
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    The TiO2 (B) nanowires with high purity had been successfully synthesized by a facile hydrothermal route using tetrabutyl titanate as titanium source . The crystal structure, morphology and purity of nanowires were characterized and analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy(TEM) and laser Raman spectroscopy (Raman) respectively, and their lithium-ion battery performance was also tested. The results indicate that the purity of the one-dimensional TiO2 (B) nanowires obtained by this method could reach to 93.2%. The obtained TiO2 (B) nanowires show excellent electrochemical properties, its first discharge specific capacity can get up to 254.8 mAh/g at 0.2C with good cycle performance, the capacity loss after 100 cycles is about 7.84%.
  • ;
    . 2015, 46(09): 30-0.
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    Under a certain condition [Ni(N2H4)3]2+ was formed by the reaction of the hydrazine hydrate with nickel sulfate. The nickel-coated toner was prepared by the redox reaction of [Ni(N2H4)3]2+ on the surface of the toner coarsened by chromic acid and concentrated sulfuric acid. XRD, TGA, SEM and EDS measurements were used to characterize the crystalline phase, morphologies, thickness and content of nickel layer for the nickel-coated toner. The results showed the toner was uniformly coated by 2-μm thick nickel, which belonged to the multangular cubic phase, and the nickel content was 44.5%.