29 December 2014, Volume 45 Issue S2

    

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研究 开发
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  Effect of Fe-doping and ball milling on the structure and magnetic properties of Sm2Co17 alloy

  Naikun SUN;

  . 2014, 45(S2): 1-0.

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  A series of Sm2(FexCo1-x)17(x=0,0.3,0.7) alloy ingots were made by arc-melting method, and then annealed for homogenization. The nanocrystalline Sm2(FexCo1-x)17 powders were prepared by ball milling the annealed sample. Effect of Fe-doping and ball milling on the phase structure, the Curie temperature and magnetic properties of the alloys has been systematically investigated. The experimental results show that upon increasing the Fe content, 1:5 phase in the alloy gradually reduces, and for x=0.7 sample, 1:5 phase disappears, forming a single-phase 2:17 type compound. Curie temperature decreases from 938℃ for the x = 0 sample to 590℃ for x = 0.7. Meanwhile ball milling process is beneficial for the formation of 2:17 phase and after ball milling for 0.5h, 1:5 phase in the alloy disappears, forming single-phase nanopowders. With an increase of milling periods of time, saturation magnetization gradually increases, while the intrinsic coercive force and magnetic energy product show a tendency of increase at first and then decrease. Samples milled for 0.5~1h exhibit optimal magnetic properties with (BH)max= 3.2MGOe, iHc=3.1kOe and 4πMs=6.5kGs for Sm2Co17 nanopowder.
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  Preparation and Thermal Properties of Phase-Change Microencapsules Incorporated with CNTs in the Shell

  . 2014, 45(S2): 2-0.

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  The phase-change microcapsules with paraffin as core and carbon nanotubes (CNTs)-doped melamine-formaldehyde (MF) resin as shell were synthesized through in situ polymerization. Their heat storage capacity，thermal stability，surface morphology and molecular structure of the synthesized microcapsules were investigated by differential scanning calorimetry (DSC), thermal gravimetric (TG) analysis, scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR) respectively. The dispersion experiment proved that the dispersion of the modified CNTs was improved greatly as designed，and the influences of the amount of CNTs on the surface morphology and thermal property of microcapsules were discussed. The results show that compared to that of microcapsule, the CNTs-doped microcapsule exhibits smoother surface and its stability was also improved. Moreover, the package rate and thermal conductivity of microcapsules increased from 60.0% to 72.4% and 0.255 Wm-1K-1 to 0.356 Wm-1K-1 with increasing the addition of CNTs, respectively.
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  Study on Photochromic Properties of phosphomolybdic acid/Silicone Coating

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  . 2014, 45(S2): 3-0.

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  A photochromic coating was prepared from phosphomolybdic acid as photochromic material and amino silicone resin as film-forming substance, and the photochromic coating could be used in the new field of auto-marking. The photochromism and photochromic stability of the photochromic coating were studied by FTIR, ESR and UV-vis spectroscopy. The results show that the photochromic coating undergoes a photoredox reaction between phosphomolybdic acid and amino of silicone resin on irradiation with ultraviolet light to form phosphorus molybdenum blue, accompanied by a color change from yellow to blue, and the color change was irreversible change.
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  The preparation and properties research of superhydrophobic organosilicone coating

  Heng LI;

  . 2014, 45(S2): 4-0.

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  The superhydrophobic coatings were prepared using dip-coating and withdrawal method，in which the monodisperse nano-particles silica spheres was modified with hydroxyl silicone resin, and the coatings were cross-linked by heat curing The research studied the effect of the size of the sol nanoSiO2 particles and content of the silicone resin on the hydrophobic performance, The variation of superhydrophobic properties of the coatings after high temperature and acid, alkaline and salt solution were discussed. The results showed that the size of the sol nanoSiO2 particles increased to 130nm, the superhydrophobicity of coating could be obtained without adding fumed nanoSiO2 further．The contact angle of the coating increased to the maximum value（151°）first，and then decreased with the concentration of organosilicone resin increasing．In addition，the coatings can keep superhydrophobicity under the 450℃ and at different pH aqueous solution and saline solution.The micro-nano hierarchical rough morphology were observed by scanning electron microscopy(SEM)
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  Effect of Ce and Homogeneous Annealing on Microstructure and Deformation Performance of Mg-2.0Zn-1.0Mn Alloy

  . 2014, 45(S2): 5-0.

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  The Mg-2.0Zn-1.0Mn magnesium alloys add Ce were deformed with extrusion simulation system, The mechanism properties of Ce element and homogenizing in Mg-2.0Zn-1.0Mn magnesium alloys and its effect on microstructure were analyzed. The results showed that the addition of Ce can effectively refine the grain ZM21 alloy to improve the mechanical properties of magnesium alloy ZM21 reduce ZM21 magnesium alloy solidification process of latent heat and solidification temperature range. Homogenization of ZM21 magnesium alloy extrusion products less affected by the performance and organization, but ZM21+Ce magnesium alloy performance and organizational impact is clear that the fracture of the two alloys are mixed fracture, in which the tendency of magnesium alloy ZM21+Ce in ductile fracture.
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  Optimization of binder’s composition for WC-Ni cemented carbide

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  . 2014, 45(S2): 6-0.

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  Optimization of binder’s composition for WC-Ni cemented carbide was studied to improve its mechanics properties. With constant content of binder, some Ni powder was replaced by equal quantitative Fe powder. The microstructure and mechanics properties of cemented carbide with different binder were studied. The r esults indicated that the growth of WC grain was inhibitted by a small addition of Fe powder. The bending strength of sintered body increased firstly and then descended, and the hardness descended with the increment of Fe powder. Mechanics properties of WC-7％Ni－1％Fe are as good as WC-Ni cemented carbide doped with Cr or Mo.
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  Study on the sensor for the Multi-point temperature sensing of liquid level measurement, Study on the sensor for the Multi-point temperature sensing of liquid level measurement

  . 2014, 45(S2): 7-0.

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  Many methods of measuring liquid level, it is difficult to achieve accurate reliable monitor the liquid level with traditional sensor. In this paper, a new sensor for the measurement of liquid level has been developed, which includes the sensor for the Multi-point temperature sensing of liquid level measurement. Design principle of sensor is based on the differences of heat transfer coefficient between liquid phase and gas phase. Experimental data have shown that the system is correct in principle, reliable and feasible in structure ,and can bear high temperature and high pressure for monitoring the liquid level in a pressure vessel and other vessels. The sensor can accurately determine the liquid and gas (vapor) the location of the interface. It’s suitable for monitoring the level in a nuclear reactor pressure vessel., Many methods of measuring liquid level, it is difficult to achieve accurate reliable monitor the liquid level with traditional sensor. In this paper, a new sensor for the measurement of liquid level has been developed, which includes the sensor for the Multi-point temperature sensing of liquid level measurement. Design principle of sensor is based on the differences of heat transfer coefficient between liquid phase and gas phase. Experimental data have shown that the system is correct in principle, reliable and feasible in structure ,and can bear high temperature and high pressure for monitoring the liquid level in a pressure vessel and other vessels. The sensor can accurately determine the liquid and gas (vapor) the location of the interface. It’s suitable for monitoring the level in a nuclear reactor pressure vessel.
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  Investigation on constitutive model and microstructure evolution of high purity titanium during hot deformation

  . 2014, 45(S2): 9-0.

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  Abstract: Isothermal compression tests of high purity titanium were performed on a Gleeble-1500 system in the temperature range between 723 K and 873 K at strain rates between 0.001 s- and 1 s-1. The flow behavior was described by a hyperbolic sine constitutive equation and the microstructures of samples were observed by electron back scattering diffraction (EBSD). The results show that during hot deformation pure titanium experienced from strain hardening to steady state deformation and the corresponding softening mechanism changes from dynamic recovery to dynamic recrystallization; Peak stress levels decreased with deformation temperature increasing and strain rate decreasing. High purity titanium is positive strain rate sensitive material. The flow stress was represented by the Zener–Hollomon parameter in an exponential equation with parameter A、α and n in expression are 1.841024 s-1、0.013MPa-1 and 12.66, with activation energy of 415.69 KJ/mol. The microstructure of specimens with different Z values show that dynamic recrystallization was responsible for softening of low Z value sample, which dynamic recovery was the main reason for dynamic softening of high Z values sample, dynamic recrystallization occurred in the sample with middle Z value. Z value can be used to justified the dynamic softening mechanism for high purity Ti material.
工艺 技术
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  Preparation and its H2-permeable characteristics of Nd doped La5.5WO12-δ

  ;Ling Wang

  . 2014, 45(S2): 10-0.

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  Mixed proton-electron conductors of (La1-xNdx)5.5WO12-δ (x=1/3, 1/2) were successfully synthesized by the solid state reaction route. The phase composition and microstructures of the samples were investigated by XRD and SEM, respectively. Chemical stability against humid CO2 was tested. The total conductivities of the samples in air and wet 5% H2/Ar atmospheres were measured by the AC impedance spectroscopy. Hydrogen permeation performance of the membranes was tested at different temperatures and hydrogen partial pressures. The results indicate that the samples sintered at 1550℃ are cubic fluorite structure and the samples are extremely dense. The samples are quite stable in humid CO2 atmosphere. The samples have higher conductivities in wet 5% H2/Ar and (La1/2Nd1/2)5.5WO12-δ presents a high conductivity in wet 5% H2/Ar, which is about 6.58×10-3 S?cm-1 at 850℃. Using 50% H2/N2 as feed gas, the highest hydrogen flux for (La1/2Nd1/2)5.5WO12-δ membrane with thickness of 1.56 mm is 0.079 mL?min-1?cm-2 at 900℃.
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  Preparation of PZT(95/5) antiferroelectric nanoscale powders using Sol-Gel method

  Hai-yun YAO

  . 2014, 45(S2): 11-0.

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  PZT(95/5) antiferroelectric nanoscale powders were prepared by Sol - gel process. 550-750℃,calcination temperature range of dried PZT(95/5) powder were identified by differential thermal analysis. Dried powders were calcinated at 550, 600, 650, 750 ℃, holding for 2 hours, respectively. XRD analysis showed that the strength of the main crystalline phase gradually increases, the impurity phase peak height decreases with the increasing of the calcination temperature. When calcinated at 750℃, single perovskite phase was formed and PZT95/5 powders size was about 100 nm.
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  Preparation of manganese oxide/carbon nanofiber composites and their electrochemical performance

  Yu-Xuan DU;;

  . 2014, 45(S2): 12-0.

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  Manganese oxide/carbon nanofiber (MnOx/CNF) composites were successfully fabricated as freestanding supercapacitor electrodes through incorporating needle-like MnO2 synthesized by a hydrothermal method into PAN solution, electrospinning and carbonization. The morphologies and structures of MnOx/CNF films were characterized by means of field emission scanning electron microscopy, transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. As a result, the MnOx/CNF films presented obvious continuous and porous structure inside the nanofibers. The electrochemical performances were investigated by cyclic voltammetry, galvonostatic charging/discharging and impedance measurement techniques. The resulting MnOx/CNF membranes exhibited great electrochemical properties, in which the sample containing 30wt% MnO2 displayed specific capacitance as high as 104F/g at 2mV/s in 0.5mol/L Na2SO4 electrolyte, great rate capability and small internal resistance.
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  Synthesis of polylactide containing sulfobetaines as a material for drug delivery systems

  ;;;;Xianglin Luo

  . 2014, 45(S2): 13-0.

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  PLA-MPS were synthesized using ring-opening polymerization of L-lactides by initiator sulfobetaines with two hydroxyl groups in ends. After the chemical structures of the polymers were confirmed, the polymers were prepared into micelles by solvent evaporation method. The critical micelle concentration (CMC) of the micelles was determined by fluorescence measurements on fluorescence spectrometer with pyrene as a probe. The particle sizes and size distributions of micelles were determined by Dynamic light scattering (DLS). β-carotene was used as a model drug. The results showed that the polymers could form stable micelles and entrap the hydrophobic drug into their micelles. So, the polylactide containing sulfobetaines may be a good candidate as a material for drug delivery systems.
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  Preparation and Thermosensitive Property of Rapid Responsive P(NIPA-co-SA) Hydrogels

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  . 2014, 45(S2): 14-0.

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  Temperature sensitive hydrogel with high LCST and rapid responsive rate was studied. The porous hydrogel P(NIPA-co-SA) was synthesized by phase separation method with NaCl solution as reaction medium. The structure of product was identified by FT-IR. The influences of the reaction medium concentration on microstructure, LCST and phase transformation response rate of products were studied by scanning electron microscope, differential scanning calorimetry (DSC) and turbidity method. The results show that P(NIPA-co-SA) hydrogel has sensitive response to temperature, which LCST is up to about 75℃. The concentration of NaCl solution doesn’t influence the LCST of product. However, along with the increase of NaCl concentration, shallow discontinuous airtight ostioles gradually appear on the surface of hydrogel, which change to open pores throughout each other. The phase transformation response rate of hydrogel gradually increases in certain degree, which has rapid response character.
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  Preparation of carbon microspheres via hydrothermal carbonization

  Jia-Zhi YANG

  . 2014, 45(S2): 15-0.

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  Carbon microspheres were prepared via hydrothermal carbonization using saccharides as raw materials. The influences of different reactants and reaction conditions on the hydrothermal carbonization were researched. The morphology, size, phase structure of carbon microspheres were characterized by scanning electron microscopy, X-ray diffraction and the hydrothermal carbonization mechanism of saccharides were discussed through FT- IR spectrum and X-ray photoelectron spectroscopy (XPS). Key words: hydrothermal carbonization; saccharides; Carbon microspheres; mechanism
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  Preparation of magnetic film by micro-arc oxidation method and its composition and structure analysis

  . 2014, 45(S2): 16-0.

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  Abstract: A super-paramagnetic film was prepared with FeSO4 solution as principal raw material on titanium alloy by micro-arc oxidation method, specific saturation magnetization of the film is 77.7A?m2/kg. A formation technology of the film was explored. The super-paramagnetic film was characterized by XRD、FT-IR、XPS and SEM etc, the results show that the super-paramagnetic film is primarily composed of Fe3O4 and (Fe2O3)x?2H2O crystals, and surface of the film is smooth and dense. Formation mechanism of the super-paramagnetic film is briefly deduced.
综述 进展
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  The Structure, preparation method and theory of graphene composites

  Zhong Liang HUYi Feng Chen;Na Li ;;

  . 2014, 45(S2): 17-0.

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  Graphene composites are of excellent properties and have extensive potential applications in many fields. At present there are a lot of papers which review the properties and applications of graphene composites, but the reviews related to their detailed preparation theories have rarely been found. The structure, preparation method and theory of graphene composites are briefly reviewed, the functionalization of graphene which is related to the preparation of graphene composites is also summarized, and the preparations of various graphene composites are reviewed one by one. Finally the facing issues and outlooks related to the preparation of the graphene composites are briefly introduced.
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  Review of failure research of infrared windows for hypersonic missiles

  Xing Liu;;

  . 2014, 45(S2): 18-0.

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  Infrared window is one of the key components of a hypersonic missile for the structure functional integration. The adverse working conditions may result in a series of serious problems such as structural and functional failure, and even lead to the breakdown of infrared detection system. So the failure research of infrared windows is getting more and more important. This paper summarized the current research situation of the infrared window failure problem in China and abroad, analyzed the cases from two aspects of design theory and related experiment. Meanwhile, this paper prospected the future development trends of infrared windows.
工艺 技术
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  Study on Methods and Properties of PVDF/Graphene Composites by Melt Blending

  Hai-Bo LIN;;;;;

  . 2014, 45(S2): 19-0.

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  The paper was aimed to study the effect of various melting process on the distribution of graphene and the resultant conductivity and thermal performances. Graphene was uniformly and mechanic ally dispersed in poly(vinylidene fluoride) (PVDF) by the synergetic action of stearic acid amide, sodium dodecyl sulfate and nano calcium carbonate through the high speed mixer. PVDF/graphene composites were prepared by the following melting methods：melt molding, molding by a double roll, mixing by a double roll, extruding, mixing by a mixer. The microstructures of the composites were characterized by scanning electron microscopy and transmission electron microscopy. The influences of different methods for melt blending on the conductivity, thermal performance and thermodynamic stability were investigated. The results indicate that graphene can be uniformly dispersed in PVDF to form a function network structure. The composites prepared by melt blending of directional melting process have better conductivity and thermal performances than those prepared by non-directional melting process. With graphene be Added, the thermodynamic stability and crystallization temperature of the composites will be improved.
研究 开发
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  Organization Structure of the Zinc and Its Influence on Electrochemical Performance

  Hua-Qing WANG ;

  . 2014, 45(S2): 20-0.

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  In this paper, the relationship was studied between the organizational structure and its electrochemical performance for the zinc electrode by metallurgical phase, XRD and cyclic voltammetry. The results show that the reversibility performance of Zn (002) single crystal is superior to Zn (100) and the oxidizing and deoxidizing abilities of the Zn (100) single crystal is superior to Zn (002. The oxidizing and deoxidizing abilities of Zn polycrystal is superior to Zn single crystal. In terms of Zn polycrystal, the dissolution was accelerated and the dislocation was of advantage for electrodeposition during the deoxidization due to a great deal of defect such as grain boundary and dislocation. The area of the grain boundary decreased due to grain growth. As a result, the local corrosion, such as the intercrystalline corrosion, was aggravated and the corrosion resistance of the Zn electrode was reduced. However, the effect of the grains size on the electrochemical performance of the Zn electrode is much less than the dislocation and other defects.
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  Bending properties of LVL wood composite at and after exposure to high temperature

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  . 2014, 45(S2): 21-0.

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  Static 3-point bending tests, with a total of 104 specimens, were carried out to study the bending properties of LVL wood composite at and after exposure to high temperature in the range from 20℃ to 225℃. The test results show that the bending strength (MOR), modulus of elasticity (MOE) and ductility coefficient (μ) of LVL wood composite at and after exposure to high temperature decrease with the increase of the temperature. However, except for the μ,both the MOR and MOE of LVL wood composite at exposure to high temperature are lower than that after exposure to high temperature. A statistical regression-based model, as a function of thermal exposure temperature, is developed and evaluated for predicted the strength loss of LVL wood composite. The predicted theoretical results are consistent with the observed values.
综述 进展
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  Annealing Effect of Perfluorinated Ion Exchange Membrane on the Properties

  ;Miao-Kun 无 YANG ;

  . 2014, 45(S2): 22-0.

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  The perfluorinated ion exchange membrane (PFIEM) is the crucial materials in the proton exchange membrane fuel cell (PEMFC) and chlor-alkali industry, which widely used in the fuel cell, chlor-alkali industry, vanadium battery, etc. As one of the key components, the structure and properties of the PFIEM determine the performance of the battery or cell. Annealing is a kind of traditional technological process, which is simple and convenient, being widely used in the research of the PFIEM performance. In this review, according to different properties of the ionic membrane, we mainly outline the annealing effect of perfluorinated ion exchange membranes on the proton conductivity, methanol permeability, mechanical properties, permselectivity, etc., respectively. The characteristics of the research at present and developing direction are summarized.
研究 开发
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  Influence of graphene on the electrochemical performance of LiCoO2 cathode materials for Lithium-ion batteries

  deng ling-feng YU Kai-ming

  . 2014, 45(S2): 23-0.

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  Graphite oxide(Go) was prepared by modified Hummer’S method, graphene was prepared by chemical reduction method, and graphene were used a conducting additives of LiCoO2 cathode materials in order to investigate the effect of graphene on the electrochemical performance of lithium ion batteries. Images of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that the surface wrinkles of graphene wrapped LiCoO2 particles to form plane contacted interface, thus enhanced the conductivity of the cathode, improved greatly the high rate cycling stability. Charge-discharge tests indicated that the addition of graphene increased the electrochemical reaction activation of LiCoO2. Compared with carbon black, the discharge capacity of LiCoO2 at 0.2C rate was improved 11 mAh/g. After 300 cycles, the capacity of graphene/LiCoO2 Battery decreased from 145.0 mAh/g to 137.8 mAh/g, which was 95.1 ％ of the initial discharging capacity.When the discharging rate increased to 20C, the discharging capacity of graphene/LiCoO2 Battery was 132.1 mAh, which was 91.1 % of the discharging capacity at a discharging rate of 1C.
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  The performance and fabrication of graphene-based electrode materials for capacitive deionization

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  . 2014, 45(S2): 24-0.

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  Successfully isolated in 2004, graphene is a two-dimentional carbon material consisting of a single layer of carbon atoms. Due to its big specific surface area and high electrical conductivity, graphene has recently attracted increasing attention regarding its potential to serve as an electrode material for CDI. This paper reviews the literature applying graphene or graphene composites (collectively called graphene-based materials) as the CDI electrode materials (published since 2009 when the first relevant paper emerged). The values of the parameters describing the electrode performance of graphene-based materials were summarized (including specific capacitance, specific surface area, average pore diameter, and electrical conductivity) and comparisons regarding those key parameters were made between different graphene-based materials. Then the NaCl electrosorption capacities of the graphene-based materials when applied in CDI were discussed and compared to those of other carbon electrode materials. Also, the fabrication techniques of graphene-based materials were summarized. Finally, prospects for future work on graphene-based materials as a CDI electrode were outlined.
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  Effect of Nanocrystallization on the corrosion behavior of low carbon steel

  Ning Wang; ;;;;

  . 2014, 45(S2): 25-0.

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  The nanocrystalline microstructure in the surface of low carbon steel induced by surface mechanical attrition treatment (SMAT) has been characterized by means of X-ray diffractometry(XRD). Then, the effects of SMAT on corrosion resistance of low carbon steel measured in 0.05mol/L H2SO4+0.05mol/L Na2SO4 solution have been investigated. The results showed that Steel 20 SMAT sample has better corrosion resistance than Steel 10 SMAT sample. It is thought-provoking that the results have been in contrast to the corrosion results in coarse grain state.
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  Microstructure of ZrB2/Ni Composite Ceramics Prepared By Hot-Pressing

  Xiao-Xuan PANG;;;;;

  . 2014, 45(S2): 26-0.

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  Four kinds of Zirconium diboride (ZrB2) powders were sintered at the same technical condition of 1950℃/50 MPa/1h by hot-pressing. They were coarse monolithic ZrB2 powders, high energy milled powders with and without the sintering additive of metal Nickel, respectively. The Archimedes method was used to measure the density of the as-sintered ceramic samples. The microstructure observation and element distribution mapping were performed by using scanning electron microscopy (SEM) and Energy Dispersive Spectrometry (EDS), respectively. The results indicated that: the density process can be described as spherical surface contact and matter diffusion when the coarse monolithic ZrB2 powders were sintered at the condition of high temperature and high press. The density behavior was profited from the augmentation of surface area and sinter active when the powder was deal with high energy mill. The sintering additive of metal Nickel was contributive to the sinter density for both thick ZrB2 powders and milled super-thin powders, but different density action between them. The Ni element was distributed at the boundary of thick granules or rudimental cavity, and it had the operation to augment the contact area of thick ZrB2 grain and accelerate the matter diffuse between the contacted ZrB2 granules. Ni element was distributed at the common boundary of ZrB2 grain, and which had the contribution for the diffusion between ZrB2 grain and the reduction of superfine cavity.
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  Synthesis and characterization of novel biodegradable succinic acid-1,4-butanediol-1,3-propanediol-urea copolymers

  ; ;Yue-Jun LIU

  . 2014, 45(S2): 27-0.

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  Low molecular weight polyester-amide prepolymers have been synthesized by melt polycondensation from succinic acid, 1, 4-butanediol, 1, 3-propanediol and urea, and the chain extension of polyester-amide prepolymers was conducted with toluene diisocynate. A series of novel biodegradable succinic acid-1,4-butanediol-1,3-propanediol-urea copolymers with Mw from 100000 to 170000 were synthesized, and then the polyester-amide films were prepared by tape casting. The effect of urea amount on the thermal properties, crystallinity, mechanical properties and biodegradation of the polyester-amide were studied. The polyester-amide were characterized by FTIR, 1H-NMR spectroscopy, GPC, TG, DSC and XRD. The results showed that the melting point and thermal stability of polyester-amide decreased with the increase of urea content. The addition of urea unchanged the crystal form of polyester phase in polyester-amide, but destroyed the regularity of the polyester chain segment, which led to the decreased crystallinity. With the increase of urea content, the mechanical properties and biodegradation of polyester-amide films were improved.
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  Determination of porous Ni-Fe-Cr foam heat-resistant alloys

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  . 2014, 45(S2): 28-0.

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  Porous Ni-Fe-Cr foam alloys prepared under different electroplating conditions, the effects of concentration of CrC13?6H2O , current density, pH value and temperature of plating solution on the compositions of the coatings were studied by energy dispersive spectrometer, and the microstructure and surface morphologies of the coatings were observed by X-ray diffraction spectroscopy, optical microscopy and scanning electron microscope. The heat-resistance property of the porous foam alloys was tested. Experiment results show that the Ni-Fe-Cr alloy coating layer by a dense arrangement and a face centered cubic structure which has good heat-resistance properties with 21.4 wt% Cr and 43.6 wt% Fe is obtained using the solution containing 160 g/L of CrC13?6H2O with pH value of 2.0 and current density of 24 A/dm2 at 30 °C for thirty minutes.
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  Study on effect of conductive agent on the performances of Ruthenium oxide electrode materials

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  . 2014, 45(S2): 29-0.

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  Abstract: Amorphous hydrous ruthenium oxide/active carbon composite electrode materials prepared by the liquid phase codeposition. Based on the cyclic voltammetry, AC impedance spectroscopy and constant current charge-discharge techniques, the performances of the RuO2/AC composite electrodes materials which add different conductive agent are investigated. The morphology of the conductive agents were investigated by SEM. The results show that when CNTs,AB,KS6 and Super P li are used as conductive agent, the materials specific capacitance of RuO2/AC composite electrodes is 689 F/g,556 F/g,574 F/g and 512 F/g, respectively, the equivalent series resistance is 0.19Ω,0.36Ω,0.32Ωand 0.41Ω, measured at 5mV/s in 38% (mass fraction) H2SO4 and under the current density of 2 mA/cm2
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  The Influence of Oxygen Concentration on the Structure and Properties of Co-SiC Fibers

  ; ;;;An-Hua LIU

  . 2014, 45(S2): 30-0.

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  In this work, it is systematically studied that how oxygen concentration of cured cobalt-containing polycarbosilance(PCS) fibers influences the structure and properties of cobalt-containing silicon carbide(Co-SiC) fibers. Compared to cured Co-PCS-Air fibers, Co-PCS-O2 fibers have a higher oxygen concentration and higher ceramic yield. For Co-SiC-O2 fibers derived from cured Co-PCS-O2, lower pyrolysis temperature is required to reach maximum mechanical properties. And higher SiCxOy content, higher growing speed and final sizes of β-SiC and CoSi grains and lower electrical conductivity are observed. Co-SiC-O2 fibers have a electrical conductivity controllable between 100 Ω·cm~ 103 Ω·cm and are magnetic to some degree, enabling this kind of fibers to have the potential to be used as wave-absorbing materials.
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  Co-continuous morphology inversion of ABS/PA6 polymer blends by OMMT

  ;;;Yang QIAN;;

  . 2014, 45(S2): 31-0.

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  In this work, a melting blending method was used to prepare acrylonitrile-butadiene- styrene (ABS)/polyamide 6 (PA6)blends with OMMT. The effect of OMMT dispersion on the morphology evolution of ABS/PA6 blends was studied by SEM, XRD and TEM. It was found that the OMMT network were selectively dispersion in the PA6 phase. The addition of OMMT leads to a phase transition from a sea-island structure to a co-continuous one. With an increase in OMMT loading (ΦOMMT), the PA6 content (ΦPA6) required for the formation of the co-continuous structure decreases, and a smaller domain size is observed. The results verified that there exists a quantitative relation between ΦOMMT and ΦPA6. The product of ΦPA6 and ΦOMMT, n, remains approximately 8 for this given system, and decreases with an increase in the DBP adsorption number of OMMT. It can offer useful reference to molding OMMT loading required on PA6 content.
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  Radiation synthesis and performance of PNIPA/CS intelligent hydrogels

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  . 2014, 45(S2): 32-0.

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  PNIPA/CS intelligent hydrogels were prepared by radiation polymerization method with an excellent thermo-sensitive monomer N-isopropylacrlamide (NIPA) and the pH sensitivity natural polymer chitosan (CS) with has good biocompatible and biodegradable properties as the basic materials. The structure of the hydrogels was analyzed by infrared spectrum, and the swelling and deswelling kinetics, the equilibrium swelling ratio were also investigated. The effects of CS content on hydrogel were studied. The results showed that the grafting reaction occurred between the C3-OH and/or C6-OH on CS molecules and PNIPA. The swelling ratio of PNIPA/CS hydrogel decreased with the increase of CS content. The swelling process of hydrogel containing 20% CS was controlled by segment relaxation and the average water loss rate was about 94%. The lower critical solution temperature (LCST) of this hydrogel is about 37℃.
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  The Effect of Calcination Temperatures on the Mophology and Structure of ZnO Nanofibers Prepared by Electrospinning

  . 2014, 45(S2): 33-0.

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  The morphology and structure of ZnO fibers calcined at different temperatures were studied in this paper. The precursor of ZnO nanofibers was prepared by electrospinning technology using PVA and zinc acetate. The ZnO nanofibers were obtained after calcination at 400, 500, 600, 800℃. Thermal Gravimetric Analysis (TGA), Energy Dispersive Spectrometer (EDS), Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), Transmission Electron Microscope (TEM) and Raman were introduced to analyze the morphology and structure of the ZnO Nanofibers. The diameters were reduced firstly and then increased with the rising of the calcination temperature from 400℃ to 800℃. The grain sizes of ZnO prepared at 400, 500, 600, 800℃ are 24.25 nm、33.52 nm、35.37 nm, respectively, which was increased with the rising of the calcination temperature. The results indicated the optimum calcinations temperature of the ZnO nanofibers is 600℃.