15 January 2010, Volume 41 Issue 01

    

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研究与开发
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  Synthesis of CeO2 Nanoparticles by Ultrasonic Template Method

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  . 2010, 41(01): 1-0.

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  CeO2 nanoparticles were successfully synthesized by ultrasonic template method combining with precursor treatment of butanol azeotropic distillation and hydrothermal method, respectively. The morphologies, structure and properties of the nanoparticles were characterized by TEM、XRD、FT-IR、UV-Vis, etc; The effects of the property of template, the amounts of template, azeotropic distillation and hydrothermal method on the grain morphology and size were investigated. The results showed that: compared with OP-10 and SDBS, CTAB (cationic surfactant) was the best choice for template. Spherical CeO2 nanoparticles (ca. 6.1nm) were prepared when the molar ratios between CTAB and Ce(NO3)3?6H2O was 1：2；The azeotropic distillation effectively reduced the template and absorption water, The replace absorption and steric effects of butoxy conducive to synthesize nanoparticles with good dispersion, uniform particle size(ca.1.5~2.2nm). hydrothermal method improved the crystallization degree of the nanoparticles, avoiding the formation of hard agglomerates during the high temperature calcinations, the particle size was about 2.5~3.8nm; CeO2 nanoparticles have high transparency in visible light and excellent UV-shielding property.
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  Photoluminescence properties of CdS and rare earth-doped CdS nanobelts

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  . 2010, 41(01): 2-0.

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  CdS and rare earth-doped CdS nanobelts were synthesized by thermal evaporation method. These synthesized nanobelts were characterized with scanning electron microscopy (SEM), X-ray diffraction (XRD) and photoluminescence spectroscopy (PL). SEM images show that each nanobelt has a uniform width along its entire length, flat and smooth surface. A typical thickness of these nanobelts is in the range of tens of nanometers. XRD pattern confirmed that nanobelts are hexagonal wurtzite structure with lattice constants a = 0.414 nm and c = 0.671 nm. Room-temperature photoluminescence spectra of the CdS nanobelt revealed that the emission band is centered at ~405 nm. The emission band of CdS:Ce3+ nanobelts is centered at ~525 nm. CdS:Er3+ nanobelts shows three emission bands centered at 525, 556, and 582 nm respectively.
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  Electroless preparation and characterization of radiation-proof polyester fabric

  YANG Wen Bin

  . 2010, 41(01): 3-5.

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  Ni-P alloy coating was covered on surface of poly(ethylene terephthalate) (PET) fabric by electroless plating technology. Morphology, structure and property of the Ni-P plating were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogrametric analysis (TG) and infrared spectrometer (IR), respectively. The results showed that the Ni-P alloy coating on surface of PET fabric, which was composed of 0.1-1μm grains, was non-crystal and owned good stability of thermodynamics. There was good adhesion between Ni-P plating and PET fabric. Compared with those before plating, the intensity of IR of PET fabric after plating were decreased. The shielding effectiveness (SE) to frequency less than 20GHz of Ni-P -coated fabric was above 60dB.
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  Thermophysical properties and bioavtivity reaearch of FHA

  ZENG Lin;;

  . 2010, 41(01): 4-0.

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  FHA(Ca10(PO4)6(OH)2-2xF2x ,0＜x＜1) powders were synthesized by wet precipitation-calcination method.XRD,TG, high-temperature dilatometer,SEM and EDS and SBF experiment were used to investigated the influences of F doping on the thermal stability and sintering properties of high temperature,thermal expansion coefficient,and bioactivity of FHA.The results show that doping F improves the thermal stability of FHA at high temperature.,and the stability can be gradually improved with the inrease of F content;Sintering density of FHA bulk increases with small amount of F doping (x=0.25),but decreases when F doping content more than x=0.25.Thermal expansion coefficient(CET) of FHA decreases with the increase of F content. The growth ability of bone-like apatite apatite forming on FHA bulk surface proved by the SBF soaking experiment is : FHA＞HA＞FA，and both F0.5HA and F0.75HA have the best bioactivity.
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  Coaty of SnAgCu alloyed powder by Stearic acid via vacuum evaporation

  ;;;;Guoji Huang

  . 2010, 41(01): 5-0.

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  Fine leadless solder alloy powder is easy to be agglomeration and oxidization, whose dispersivity and antioxidation can be improved by surface modification technique. In this paper, the raw material is SnAgCu alloy powder which is produced by the method of close-coupled gas atomization. It was used that vacuum evaporation modify SnAgCu alloy powder by coating stearic acid.The influence of the vacuum evaporation temperature and time on modification effects of SnAgCu alloy powder were studied. Scanning Electricity Microscope (SEM) and Transmission Electricity Microscope (TEM) were used to observe the appearance and structure of coating alloy powder and X-Ray Photoelectron Spectroscopy(XPS) and carbon-sulfur united testing instrument were adopted to measure photoelectron energy and test C contents of the coating powder. The result indicated that the appropriate conditions of vacuum evaporation were: 70℃ for 12h and lower than 1.6×10-2Pa vacuum degree. In this condition, uniform and compact coating, whose thickness was 5-10nm, could be obtained. The growth mechanism of stearic acid coating SnAgCu alloy powder was following volmer-weber, and the coating behavior was a process of physical adsorption.
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  The influence of quality of ultrafine powder on microstructure and properties of binderless tungsten carbide

  . 2010, 41(01): 6-0.

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  Bulk binderless ultrafine pure WC was obtained by the spark plasma sintering process(SPS). The phase ,microstructure and fracture surfaces of the binderless WC were studied by using X-ray diffraction analysis(XRD), optical microscopy and scanning electron microscopy(SEM). The experiment results show that, when free carbon of the initial power was too high,abnormal grain growth occurred; when the content of Oxygen of the initial power was too high,the density of sintered decreased badly.The binderless WC sintered at 1700℃ for 120s showed almost full densification and exhibited excellent mechanical properties when using the best power,the Vickers hardness and fracture toughness obtained were 2566 Kgf/mm2 and 6.2 MPa/m1/2.In addition, It was found that the content of Oxygen could be reduced obviously when the initial WC power was pretreated in H2 atmosphere at 500℃.Then,the binderless tungsten carbide was prepared at 1700℃.The density,Vickers hardness and fracture toughness of alloys is 98.8%, 2731Kgf/mm2 and 6.16 MPa/m1/2 respectively.
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  The Effect of pH Value on Sol-gel Combustion Synthesis of Nanocrystalline LaMnO3 Powders

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  . 2010, 41(01): 7-0.

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  Abstract Nanocrystalline LaMnO3 powder was synthesized by sol-gel combustion synthesis. The influence of pH value of the precursor solution on the combustion behavior and as-synthesized powder were investigated with the help of thermal analysis, infrared spectra, X-ray diffraction technique and scanning electron microscopy. The results showed that nanocrystalline LaMnO3 powders can be synthesized by sol-gel combustion technique. The combustion rate increased with the pH value increasing. The crystallite size of the as-formed LaMnO3 powder decreases with pH value increasing. LaMnO3 powders with particle size less than 200 nm can be obtained by control the pH value.
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  Voltage controlled color tunable organic light-emitting diodes

  NIU Jing-Hua;

  . 2010, 41(01): 8-0.

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  We demonstrate a simple model for the voltage-induced alteration of emission color from the organic light emitting diodes (OLEDs) based on 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) doped into 2,9-dimethyl-4,7-diphenyl-1,10-phenenthroline(BCP).The device displays a continuous change of color from orange to purple depending on the applied bias. The emitting characteristics can be rationalized by the potential energy barriers at the interface between different layers.
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  Research on the Moisture Absorption Properties of Polyacrylamide and its Porous Material

  . 2010, 41(01): 9-0.

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  In this paper, polyacrylamide (PAM) was synthesized with acrylamide as monomer, N,N’-methylene bisacrylamide as crosslinking agent , sodium sulfite and ammonium persulfate as initiator by means of aqueous solution polymerization. The factors such as monomer concentration, hydrolysis degree, crossing-linking agent concentration and so on influencing on moisture absorbency were systematically investigated. Under the condition of T=20℃,RH=90％,the moisture absorption property of PAM was obviously better than the traditional materials,such as silica gel and molecular sieve.PAM/PEG and PAM/ CaCO3 porous materials were synthesized by using polyethylene glycol and calcium carbonate as pore-foaming agent respectively. Experimental results indicated that the moisture absorption rate of PAM/PEG was increased by more than 50% and its moisture absorption capacity was markedly improved than PAM too.Nevertheless,the moisture absorption ability of PAM/ CaCO3 was not satisfactory. TGA analysis verified that the thermal stability of PAM/PEG was decreased but PAM/CaCO3’s got improved.
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  Multi-walled Carbon Nanotubes Supported Mg-doped ZnO Nanoparticles

  . 2010, 41(01): 10-0.

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  MWNTs/Mg-doped ZnO composite were synthesized by co-deposition method and heat treatment, using zinc acetate and magnesium acetate as raw material, anhydrous ethanol as solvent and oxalic acid as precipitator. The images and optical property of MWNTs/Mg-doped ZnO composite were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and ultraviolet-visible (UV) absorption spectrophotometer. The experimental results of electron microscopy show that after treatment at 450 ℃, the surface of MWNTs is supported by Mg-doped ZnO nanoparticles with sizes in the range of 10-20 nm. The UV absorption spectroscopy reveals that Mg-doping can improve the UV absorption ability of MWNTs/ZnO composite, and the maximum blueshift reach 22nm。
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  Preparation and growth mechanism of ZnO thin films by chemical solution deposition with PVA

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  . 2010, 41(01): 11-0.

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  Highly c-axis oriented zinc oxide (ZnO) thin films were prepared by CSD with polyvinyl alcohol (PVA). The effect of annealing temperature and coating thickness on the ZnO thin films was characterized by XRD, Raman and AFM. It was shown that crystallinity and the root-mean-square of these thin films were enhanced with increasing annealing temperature in some degree. Meanwhile, the c-axial orientation of the ZnO films decreased with increasing the coating thickness. Growth mechanism can be described as follows: homogeneous and heterogeneous nucleation happened simultaneously in each layer while heating the coated films, and once the grains got into contact with neighboring one, coarsening occurred in each direction. As the coarsening process continued, the grain sizes became larger and continuous ZnO(002) films with columnar and granular structure can be obtained at last.
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  ELECTROSPINNING OF REGENERATED SILK FIBROIN/SERICIN BLEND AQUEOUS SOLUTIONS

  HANG Yi-chun

  . 2010, 41(01): 12-0.

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  In this paper, regenerated silk fibroin/sericin (SF/SS) composite fibers were prepared using electrospinning method. The influence of SF/SS ratio on the rheological behaviors and the spinnabilities of the blend solutions were studied. The morphology and structure of the electrospun fibers were characterized by SEM, Raman Spectroscopy, WAXD and DSC, respectively. Their mechanical properties were also investigated. It was found that with the increase of SS amount, the apparent viscosity of the blend solutions increased, while the average diameter and diameter distribution of the electrospun fibers decreased. The addition of SS in the regenerated SF aqueous solution induced the conformational transition of SF from random coil or α-helix to β-sheet structure and further improved the tensile strength of the regenerated SF/SS electrospun fibers.
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  Study of a new style heat resisting spring alloy about properties

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  . 2010, 41(01): 13-0.

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  Abstract:anti-relaxation property ,elastic modulus, spring torgue are emphasisly studied, In this article about heat-resisting spring alloy.reserch different heat treatment processes affecting anti-relaxation rate,as soon as spring torgue change with turning angle. The results prove the studing spring superior to Imported Products,the torgue meeting need of National-key-machine,affter arriving torque value 6.86N.M, rotating 90 degrees,testing torque value 5.12N.M, in general case, rotating 90 degrees testing torque value from 5.45N.M to5.65N.M. Calculated value of the elastic module temperature coefficient is 3.91×10-4/℃.In 610℃,change of elastic modulus relative room temperature isΔE/E。=23.78%。
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  Preparation of TiO2-PTFE Compound Coating on TC4 Titanium Alloy

  . 2010, 41(01): 14-0.

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  TiO2-PTFE compound coating was prepared on the surface of TC4 titanium alloy by the special chemical and physical method. The lubricant film was composed of hard anodic oxidation film and PTFE with low friction factor, which had excellent self-lubricant property. Microstructure and morphology, phase composition and element composition of TiO2-PTFE compound coating were investigated. The effect of anodic oxidation treatment process and coating time on the coating volume of PTFE was discussed. Results of the experiment showed that after anodic oxidation, the nanometer TiO2 porous film was consisted of annatase and rutile phases formed on TC4 titanium alloy. After being coated with PTFE, the surface and film hole were covered by PTFE polymer. The PTFE coating volume kept stable after the samples of TC4 titanium alloy being treated in different voltages and different oxidation time. As the coating time prolonging, the PTFE coating volume increased rapidly in the first 5~20min, the coating volume increased slowly after more than 20min.
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  Electrode Performances for Supercapacitors of Activated Carbon Derived from Foams

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  . 2010, 41(01): 15-0.

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  Two kinds of activated carbon were obtained from phenolic resin and coal tar pitch carbon foams by vapor activation, with specific surface area of 961m2/g and 953m2/g respectively. Their morphology and pore structure were characterized with scanning microscope and BET nitrogen adsorption instrument, while the charge discharge performance was investigated by constant current and cyclic voltammetry methods. The results showed that, the phenolic sample owns more abundant and larger micropores under 1.0nm than the pitch’s. The larger micropore size benefited its charge discharge performance especially at higher current. Working at 1.0mA, the two samples showed similar capacitance, which was 106.28 F/g and 105.1F/g for the phenolic and the pitch’s respectively. However, when working at 50mA, they performed much differently, the capacitance for the phenolic and the pitch’s decreased to 41.94F/g and 17.23F/g respectively, showing that the micropores under 1.0nm obviously effected on the performance of the anode material. Cyclic voltammetry test showed the electrochemical window for phenolic carbon was wider than that of pitch carbon at 100 mV/min.
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  Preparation and properties of magnetic 5A zeolite

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  . 2010, 41(01): 16-0.

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  Magnetic influence of Fe3O4 was prepared by coprecipitation method, and then prepared magnetic 5A zeolite with different loadings of Fe3O4, the production were characterized by X ray diffraction, scanning electronic microscopy, energy dispersive spectrometer and vibration sample magnetometer, the magnetic recovery rate and saturation exchange-adsorption capacity to copper, zinc, cadmium ion were also measured. The results show that Fe3O4 particles mainly occurrence between the grains of 5A zeolite, magnetic 5A zeolite show well characteristic of superparamagnetism, and the saturation exchange-adsorption capacity to copper, zinc and cadmium ion of magnetic 5A zeolite are approximate with 5A zeolite, but decrease slightly along with the loadings of Fe3O4 increasing. When the loadings of Fe3O4 is 25%, the saturation magnetic induction and remanence magnetization of magnetic 5A zeolite is 13.817, 0.351 emu·g-1, magnetic recovery rate is 98.78%, saturation ion exchange-adsorption capacity to copper, zinc, cadmium is 77.1, 70.8, 135.3 mg·g-1, respectively.
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  Effect of blending DyHx addition on the properties and microstructures of sintered Nd-Fe-B magnet

  Liu Guo Jun

  . 2010, 41(01): 17-0.

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  The effect of Dy on the properties and microstructures of sintered Nd-Fe-B with addition of various amounts of DyHx powder to Nd31.5FebalB6.0Co1.2Cu0.04（wt%） as a precursor alloy has been investigated. It is found that Dy is only located in the intergranular phases, and there is no diffusion of Dy into the matrix phase；It makes the grain more refined and uniform, and can effectively control the abnormal grain growth. Meanwhile, the microstructure of grain boundary has been improved; In addition, intrinsic coercivity Hcj is obviously increased with 0.5wt% DyHx addition. However, it is not easily improved and the density of magnets drastically decreases when the amounts of DyHx addition are more than 1.0wt%.
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  PREPARATION AND CHARACTERIZATION OF VOLTRAREN CHITOSAN HYDROGEL MICROSPHERES

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  . 2010, 41(01): 18-0.

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  Chitosan hydrogel microspheres (CHM) cross-linked with glutaraldehyde have been prepared in Span80/soja salad oil reverse micellar system. The structural characterization and the shape of the cross-linked CHM were studied by TEM and IR methods. Additional, the swelling degree of CHM and the release behavior of voltraren loaded in CHM in vitro were also studied. The results show CHM shows the satisfying function of controlling drug release. The diameter, the swelling degree and the capability of loading drug and controlling release of CHM depend largely on the cross-linking degree.
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  DESORPTION ACTIVATION ENERGY OF BENZO [a]PYRENE ON SY-6 ACTIVATED CARBONS by MODIFIED DIFFERENT METAL SALT SOLUTIONS

  LI Jing

  . 2010, 41(01): 19-0.

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  Abstract: This work is mainly concerned with the study of the effects of loading different metal ions onto activated carbon surfaces on the desorption activation energy of Benzo[a]pyrene (B[a]P). Temperature Programmed Desorption (TPD) experiments were conducted to measure the desorption activation energy, Ed, of B[a]P) on the activated carbons separately dopped with ions Fe3+, Zn2+ , and Ag+, and the effects of loading metal ions onto the activated carbons on the interaction between B[a]P the carbon surfaces were discussed. Results showed that the Ed of B[a]P on the activated carbons followed the order: Ag(I)/AC > AC > Zn(II)/AC > Fe(III)/AC. In comparison with the unmodified activated carbon AC, the loading of Ag＋ onto the activated carbon surfaces enhanced the interaction between B[a]P and the surfaces, while the loading of Zn2+ and Fe3+onto the activated carbon surfaces weakened the interaction between B[a]P and the surfaces so that the Ed of B[a]P on the surfaces became smaller to some extent. The results were discussed by HSAB.
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  THE MODIFICATION OF AMIDO ON THE SURFACE OF THE DIAMOND FILM DEPOSITED BY HFCVD

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  . 2010, 41(01): 20-0.

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  Diamond is some one kind of functional material that combines many kinds of fineness in itself, but the high stability of the structures of sp3 Carbon bonds in the diamond film makes it difficult to form active surface so as to meet the needs as functional surface. This paper summarized a new chemical modification method to introduce amido groups on the surface of the diamond film. The modified surface was characterized by XPS (X-ray photoelectron spectroscopy). The results indicate that the amido groups have been modified on the surface of the diamond film successfully. Finally the application of the amido groups modified diamond surface is discussed briefly.
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  Effects of reaction-microenvironment on the crystal microstructure and properties of metal-doped hydroxyapatite

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  . 2010, 41(01): 21-0.

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  Ca(NO3)2, (NH4)2HPO4, AgNO3 and Cu(NO3)2 were used as the starting materials to synthesize the Ag+,Cu2+-doped hydroxyapatite (Cu/Ag/HAP) with coprecipitation synthesis method. It was known that how the reaction-microenvironment influenced upon the crystal lattice parameter, crystal habit and thermal stability of doped hydroxyapatite by using X-ray diffraction (XRD), scanning electron microscope (SEM). The results show that the doped hydroxyapatite crystal are styliform shape,and it have preferable thermal stability and profit to grow in the c-axis preferentially in the phosphor-microenvironment; however the doped hydroxyapatite are special petaloid crystal in calcium- microenvironment.
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  Supercapacitive properties of formic acid-doped polyaniline with different morphology

  Wang Hongqiang

  . 2010, 41(01): 22-0.

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  【Abstract】Formic acid-doped polyaniline nanomaterils with different morphology have been synthesized successfully by interfacial polymerization with FeCl3 as oxidant and HCOOH as dopant. The morphology and structure of polyaniline were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Symmetric redox supercapacitor was assembled with the polyaniline as active electrode material and 1 mol?L-1 H2SO4 aqueous solution as electrolyte. The electrochemical performances of the supercapacitor were investigated by cyclic voltammetry and galvanostatic charge-discharge. These results show that polyaniline with different morphology depend on the concentration of formic acid. polyaniline with fiber morphology has better power characteristic and cycle performance in the application of supercapacitor,whose specific capacitance is about 292.2 F g-1 at the current density of 15 mA cm-2. After 500 charge-discharge cycles its specific capacitance was about 200.6 F g-1 and its capacitance retention is 68.7%.
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  Hydrothermal Synthesis of ZnO and Its photoluminescence

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  . 2010, 41(01): 23-0.

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  Zinc oxide powders were hydrothermally synthesized at 180 oC for 15 h by using ZnCl2 as starting materials, NaOH as a mineralizer. The crystal structure, morphology and optical property of the final products were characterized by X-ray diffraction, scanning electron microscopy and photoluminescence spectra. The results show that ZnO morphology change from one-dimension rods to three-dimension flowers with increasing pH from 9 to 14. The formation mechanism of the ZnO flowers was proposed and the optical properties of the final products synthesized in different pH were discussed.
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  Formation mechanism, size control and magnetic properties of CoNi nanoparticles prepared by polyol method

  Gaowu W. Qin;;;;

  . 2010, 41(01): 24-0.

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  The morphology, composition, structure and magnetic properties of CoNi nanopartiles prepared at 150~190℃ for various times have been examined by using scanning electron microscopy assisted with energy dispersive spectropy of X-ray (SEM-EDX), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The results show that all of the CoNi nanoparticles prepared above are of face centered cubic (FCC) structure. The Co2+ ions are easier to be reduced than Ni2+ ions, which results in ~78at.%Co in the initial CoNi nanoparticles within 10 min at 180℃ with high saturation magnetization (Ms) and coercivity (Hc). With prolonging reaction time, the Co content in the CoNi nanoparticles decreases, together with the lower Ms and Hc. The reduction of Ni2+ ions can be enhanced by increasing temperature in the range of 150~190℃, and the CoNi nanoparticles prepared at higher temperature have low Ms and Hc. With the addition of nucleating agent K2PtCl4, the mean diameter of CoNi nanoparticles decreases rapidly but the Hc increases mildly. The addition of K2PtCl4 does not affect the composition and structure of CoNi nanoparticles, but the particle size can be tunable in the range of 96~580 nm with the proper addition of K2PtCl4. The formation mechanism of CoNi nanoparticles has been finally discussed in detail based on the present results.
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  Synthesis and Influence Factors of ZnO Self-assembled Microspheres via Microwave Hydrothermal Method

  ZHU Zhen Feng

  . 2010, 41(01): 25-0.

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  Fine crystallized ZnO and its self-assembled microspheres were synthesized by microwave hydrothermal method using Zn(NO3)2?6H2O and PEG2000 as raw materials. The as-prepared samples were studied by XRD, EDS, SEM, and TEM. The influence factors (such as reaction time, temperature, surfactant and ultrosonic treatment) on the features and structures of samples were studied systematically. The results showed that the average diameter and length of ZnO rods were about 300nm and 1μm, whereas the diameter of self-assembled microspheres was about 2μm. The growth process of self-assembled microspheres was possibly associated with the directing effect of PEG. template The irradation time had little impact on the crystal formation of samples, by increasing reaction time the diameter of ZnO microspheres could be enhanced. The integrality of the self-assembled microspheres relied a lot on the reaction temperature.
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  Ni nanotube arrays fabricated by selective etching and its magnetic properties

  . 2010, 41(01): 26-0.

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  Ordered Ni/Cu nanocable arrays with Cu core and Ni shell were fabricated by electrochemical template synthesis based on anodic alumina membranes and Ni nanotube arrays were then obtained by selective etching the Cu cores from Ni/Cu nanocable arrays. Magnetic hysteresis loop shows that Ni/Cu nanocables and Ni nanotubes possess uniaxial anisotropy with the easy axis along the arrays, indicating their potential applications in the high density perpendicular magnetic recording.
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  Studies on synthesis and electrical properties of large boron-doped gem diamond crystals under HPHT

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  . 2010, 41(01): 27-0.

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  In the paper, the synthesis of boron-doped diamond single crystals was studied under 5.4 GPa and 1200-1400 ℃. The boron-doped diamond crystal, with 1.01 ct in weight and 6.0 mm in size, was synthesized successfully. The effect of the content of boron added in synthesis system on the Light transmittance of diamond crystals was studied. By current-voltage characteristics and hall measurements, the relationships of room temperature resistivity, hall coefficient, hall mobility and the content of boron added in synthesis system, were obtained. We found that the room temperature resistivity and the hall mobility were all decrease by the content of boron additive increasing. While the content of boron additive increases, the hall coefficient decreases firstly, and increases afterwards. By the content of boron additive increasing, the decrease of room temperature resistivity of the boron-doped diamond crystal indicates that boron has entered into diamond crystal. The reason, why hall mobility decreases by the increase of boron additive, may be that the carrier is scattered by increasing crystal defects. The change of hall coefficient is due to the increase of the boron entering into diamond crystals and crystal defects.
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  RESEARCH ON POROUS MATERIALS FROM BICONTINUOUS MICROEMULSION POLYMERIZATION

  ;Jie Yang

  . 2010, 41(01): 28-0.

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  The preparation of porous materials by Inverse microemulsion (W/O) or bicontinuous microemulsion has been an attractive research.This task makes an study on porous oil absorption material from microemulsion polymerization: methyl methacrylate (MMA) and butyl methacrylate (BMA) were in the presence of comonomer (oil phrase) while sodium dodecyl sulfate (SDS) and n-butanol(AR) formed a emulsification system, ethanol (Alc) was dispersed in the water to form a mixture aqueous with azobisisobutyronitrile (AIBN) as an initiator and adjust the proportion between oil phase and water to prepare biocontinuous microemulsion. The polymerization was conducted without stirring. The SEM indicates that continuous porous materials will be observed if the content of mixture aqueous is between 30wt% to 43wt%. The paper only makes an introduction on the preparation process and the characterization of porous material.
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  Effect of synthesis scanning rate on the electrochemical capacitance of the PANI/CNTs composite

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  . 2010, 41(01): 29-0.

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  Cyclic voltammetry (CV) was used to deposit carbon nanotube / polyaniline (CNTs / PANI) composite materials with different scanning rate. And the electrochemical performances of the obtained materials were studied with 10, 20, 50, 100 and 200 mV/s scanning rates. The results showed that the micro-structure and conductivity of composite materials was enhanced by the carbon nanotubes (CNTs) large surface area and excellent conductivity. At the same time, the obtained material was the nuclear - shell structure, which was good for enhancing the chances of material and the electrolyte. When the scanning rate was 20 mV/s, the obtained composite had the best conductivity and electrochemical capacitance. The single-electrode special capacitance was up to 397 F?g-1 with the 22 A?m-2 charging-discharging current density, which was much greater than that of the pure polyaniline (about 205 F?g-1).
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  Investigation on the microwave transmission change of the laser ablation glass-fiber resin composite

  WANG Li-Jun

  . 2010, 41(01): 30-0.

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  The change of microwave transmission on the laser ablation glass-fiber resin composite, GFRC, was invested by means of researching on the laser irradiated sample. The IR spectra was analyzed to describe the microstructure alter, and the surface picture was observed with the scanning electron micrograph. The measurement of the microwave transmission was discussed on the variety of the structure and the physical properties. It was shown that laser ablation result in the change of GFRC composition and form. It was recombined as multilayer structure with ablation layer, carbonization layer, pyrogenation layer and primary layer. Distinct change in both ablation layer and carbonization layer lead to the microwave scatterring and absorption. The microwave transmission was reduced in the mechanics.