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    10 November 2005, Volume 26 Issue 11
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    Articles
    Synthesis of YSZ Film by Solid Single Source PE-MOCVD Method and Characterization
    LIU Ming-Fei, JIANG Yin-Zhu, GAO Jian-Feng, WANG Yan-Yan, MENG Guang-Yao
    2005, 26(11):  1981-1985. 
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    Yttria-stabilized zirconia(YSZ) film was successfully deposited onto NiO/SDC and α-Y2O3 substrates by solid single-source PE-MOCVD from Y(DPM)3 and Zr(DPM)4.The influence of various substrates on the film growth and micro-structure was studied.The delivery mechanism of the precursors and the film growth kinetics were also discussed.The Y content in the film,which was found lower than that in the precursor mixture according to the XPS analysis was determined by the temperature of the sublimation region,the content in the mixture,and the precursor feeding rate.When fixing the precursor feeding rate at 1.2 mg/min and the temperature of sublimation region at 230-280 ℃,approximately 15%Y2O3 content in the precursor mixture was needed to deposit YSZ film of 8%Y2O3.The thin film is amorphous,and can be converted into single cubic phase after sintering at 1 100 ℃ for 3 h.The grain size is about 100 nm and the film growth rate is about 7 nm/min.
    In-situ Induced Growth to Mono-dispersed Hollow M-type Barium Ferrite Sub-micro-spheres
    GAN Zhi-Ping, GUAN Jian-Guo
    2005, 26(11):  1986-1989. 
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    In this paper a new method for fabricating mono-dispersed hollow M-type barium ferrite sub-micro-spheres was provided.That is to say,templated on the poly(styrene-co-acrylic acid) latexes which are surface-modified in a guanidine carbonate solvent,the barium ferrite precursors are in-situ induced to anchor on the surface and grow up,so was prepared the poly(styrene-co-acrylic acid)/barium ferrite precursor core-shell composite particles with uniform compact shell.Further heat-treating to the involved particles leads to mono-dispersed intact-frame hollow M-type barium ferrite sub-micro-spheres with pure BaFe12O19crystal phase.
    Preparation of Blue Long Afterglow Phosphors CaAl2O4:Eu2+,Nd3+ and Its Luminescent Properties
    WANG Yu-Hua, WANG Lei, ZHANG Shui-He
    2005, 26(11):  1990-1993. 
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    A series of single-phase long afterglow phosphors Ca(1-x-y)Al2O4:Eu2+x,Nd3+y(0≤x≤0.045,(0≤y≤0.0037)) were prepared by the traditional solid state reaction method and their photoluminescence were investigated.Intense blue emission of the samples was observed with a broad band peak at about 440 nm,which is due to the 4f 65d→4f 7 transition of Eu2+.The effect of different rare earth contents on the afterglow properties was investigated and the optimum content of Eu2+ and Nd3+ are x=0.001 25 and y=0.002 5 respectively.Initial brightness and persistent afterglow time of the corresponding sample is over 1 200 mcd/m2 and more than 1 000 min.60 min later,its brightness is still over 10 mcd/m2.Thermoluminescence and positron annihilation methods were used to investigate the effect of Nd3+and Eu2+ co-doping on their luminescent properties.
    Hydrothermal Synthesis and Characterization of a New Two-dimensional Lanthanum(Ⅲ)-cobalt(Ⅱ) Heterometallic Coordination Polymer La(Hida)Co(ida)2·0.5H2O
    HE Jiang-Hua, YU Ji-Hong, LI Guang-Hua, BI Ming-Hui, XU Ru-Ren
    2005, 26(11):  1994-1997. 
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    A new lanthanum(Ⅲ)-cobalt(Ⅱ) heterometallic polymeric complex of La(Hida)Co(ida)2·0.5H2O(1,ida=iminodiacetate) was hydrothermally synthesized and structurally characterized by the elemental analyses,IR spectrum and the single-crystal X-ray diffraction.The structure of compound 1 consists of one-dimensional lanthanum-cobalt heterometallic chain,which was linked via "linear" tetradentate ida ligands to form the two-dimensional framework.The crystal data for compound 1: monoclinic system,space group(C2/c,) a=0.970 78(19) nm,b=2.412 8(5) nm,c=0.859 64(17) nm,β=114.91(3)°,V=1.826 3(6) nm3,Z=4 and R=0.012 6. Interestingly,the title compound contains ten-coordinate lanthanide(Ⅲ)(ions), which makes it unique as the heteronuclear lanthanide iminoacetate.
    Encapsulation of Organic Pigments Yellow with Nanosilica Particles
    YUAN Jun-Jie, ZHOU Shu-Xue, YOU Bo, WU Li-Min
    2005, 26(11):  1998-2001. 
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    The organic pigment was successfully coated with colloidal silica particles by using layer-by-layer assembly technique.It was found that the nano-silica content adsorbed onto organic pigments could be modulated by the numbers of both polyelectrolyte layers and silica layers.TEM, TGA analysis and XPS data illustrated that the nano-silica could not cover the organic pigment surface completely,however,the coverage ratio of nano-silica on the organic pigment increased with increasing the layers.The nano-silica particles coated onto the surfaces of organic particles could obviously improve the wettability of the organic pigment,as well as weatherability through scattering of UV ray.
    Thermal Decomposition Behavior of Metal-oxygen Clusters with Keggin Structure
    KONG Ai-Guo, ZHANG Su-Mei, ZHANG Da-Wei, LV Li-Li, JIN Chao, SHAN Yong-Kui
    2005, 26(11):  2002-2006. 
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    In this paper,the thermal decomposition behavior of the polyoxometalates with a Keggin structure(YmHnXM12O40)(X=P,Si,Ge;M=W,Mo,Y=NH+4,K+,Cu2+) was investigated systematically by using Xray diffraction and IR spectra at different temperatures,TG-DTA and solubility experiment methods.Their precisely decomposed temperatures were obtained,and the procedure of decomposition was also explored.The determinant criterions of the thermal decomposition and the factors affecting the thermal property of the polyoxometalates were discussed and some new views were presented.At the same time,the main decomposition products of the prepared polyoxometalates were identified by XRD.
    Hydrothermal Synthesis and Structure Characterization of an Acidic Cerium Sulfate Hydrate,H3O[Ce(SO4)2(H2O)3] H2O
    XIN Ming-Hong, WANG Ying, ZHU Guang-Shan, SUN Jin-Yu, XUE Ming, SUN FU-Xing, FANG Qian-Rong, TIAN Ge, GUO Xiao-Dan, QIU Shi-Lun
    2005, 26(11):  2007-2009. 
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    An acidic cerium sulfate hydrate,H3O[Ce(SO4)2(H2O)3] H2O,was hydrothermally synthesized and characterized by single crystal X-ray diffraction.The compound crystallizes in monoclinic system,space group P21/c with cell parameters: a=0.677 8(3) nm,b=1.908 2(7) nm,c=0.882 7(3) nm,β=97.332(7)°,V=1.115 5(7) nm3,Z=4,R1=0.029 5,wR2=0.065 0,GOF=0.974.It possesses a layered anion framework constructed of CeO9 tetradecahedra and SO4 tetrahedra with H3O+ ion and H2O molecules located in the aperture of the inorganic layers to balance the negative charge of the framework and stabilized the three-dimensional structure by hydrogen bonding within and between the neighboring layers.The thermal analysis of the compound was also carried out.
    Segment Threshold Wavelet Denosing of Chemiluminescence Signal from Micro-fluidic Electrophoresis Chip
    FAN Jun, LIANG Heng, SHI Xiao-Qiang
    2005, 26(11):  2010-2014. 
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    The denoising methods based on wavelet transform have been widely applied to eliminate the noise in the chemical measuring signals.However,the general wavelet-denoising methods do not effectually clear away the heteroscedastic noise in some chemical signals.In this contribution,the segment threshold wavelet denoising(STWD) method is proposed to eliminate the heteroscedastic noise that arises in the chemiluminescence detection signal of micro-fluidic electrophoresis chips.In the STWD,the wavelet denoising thresholds are independently chosen one segment by one segment according to the noise variances.Two synthetic signals(one with the general white noise,another with the heteroscedastic noise) were used to verify the validity of the STWD when the different parameters of wavelet denoising were adopted,and the STWD with optimized parameters was also applied to denoise the chemiluminescence detection signals of micro-fluidic electrophoresis chips.In comparison with the general wavelet denoising method,the STWD showed the better denoising effects in the two synthetic and the chemiluminescence signals.It indicates that the STWD could considerably improve the denoising performance of the signals with heteroscedastic noises.
    A Novel Method of Fast Sample Pretreatment for in situ Determination of Formaldehyde in Water-soaked Foodstuffs
    WANG Xing-Hua, LI Bao-Hua, XIE Fei, HUANG Feng, MA Jun, YU Ai-Min
    2005, 26(11):  2015-2018. 
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    A simple,rapid method for sample preparation for in situ determination of formaldehyde in water-soaked foodstuffs was developed.The advantage of this method is that the sample pretreatment and the color reaction can be finished simultaneously.The protein and the fatty compounds in the sample are precipitated by zinc acetate and potassium ferrocyanide,then the chromogenic reaction of acetylacetone with formaldehyde released from the sample in weak-acid medium and boiling bath takes place immediately.Various experimental parameters were studied and optimized,so the analysis of each sample can be completed in 10 min. More than 100 kinds of practical samples were analyzed.The results were in good agreement with those obtained by the standard method,and the relative errors of determined values were less than 5% if the formaldehyde concentrations were more than 10 mg/kg.The background concentration of formaldehyde in practical samples and the standard for judging samples containing spiking formaldehyde were studied.The determined values less than 10 mg/kg were regarded as the background concentration of formaldehyde in samples,and the determined values more than 20 mg/kg were regarded as the evidences that the samples contained spiking formaldehyde.
    Preparation of Monolithic Microcolumn Filled with Quartz Sand and Its Separation Property of Reversed-phase Electrochromatography
    DENG Ning, HE You-Zhao, WANG Xiao-Kui, WANG Lei, SU Qing-De
    2005, 26(11):  2019-2022. 
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    Capillary electrochromatography(CEC) possesses advantages of high separation efficiency and selectivity,but it shows some shortcomings,such as low sample loadability and restricted concentration detectability,due to its small inner diameter.In this paper,a silica gel monolithic microcolumn with high surface area was prepared by sol-gel polymerization of tetraethoxysilane under acidic conditions,which was filled with fine quartz sand in 2.2 mm i.d.fused silica tube.The experiment results indicate that the heating effect caused by electric current in the large diameter microcolumn was eliminated by packing fine quartz sand.With the mobile phase driven by electroosmotic flow,two aromatic compounds were separated successfully by the reversed-phase electrochromatography.The experiment results indicate that the microcolumn can be used for electrochramatography separation and its detection sensitivity compared with CEC can be improved.
    Studies on Interaction of Atorvastatin Calcium with β-Cyclodextrin and Its Application
    DONG She-Ying, HUANG Ting-Lin, ZHENG Jian-Bin, GAO Hong
    2005, 26(11):  2023-2026. 
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    The interaction of Atorvastatin calcium(AC) with β-cyclodextrin(β-CD) was studied by means of linear scan voltammetry,cyclic voltammetry and UV spectra.The experimental results show that electroactive molecule AC was complexed with β-CD to form 1:1 inclusion complex in 0.06 mol/L KH-2PO4-Na-2HPO4(pH=7.17) buffer solution.The inclusion constant was calculated to be 9.09×104 L/mol by electric current method.In addition,an inclusion complex between β-CD and AC in NaOH solution was formed,which induced the decrease of adsorptive peak current of β-CD.Based on the characteristics,an indirect voltammetry for AC determination was found,and this method was more sensitive than the direct method.
    Fingerprint Analysis of the Volatile Chemical Constituents in Artemisia Capillaris Herba via Gas Chromatography-Mass Spectrum
    GUO Fang-Qiu, LIANG Yi-Zeng, HUANG Lan-Fang, XU Cheng-Jian
    2005, 26(11):  2027-2030. 
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    GC-MS fingerprint of the volatile chemical constituents in Artemisia capillaris herba was built,and orthogonal projection resolution was adopted for the extraction of common peaks from different sources of Artemisia capillaris herba.The criteria of common peak rate,variance coefficient and similarity were adopted for the evaluation of four different Artemisia capillaris herba samples from Hebei,Gansu,Shandong and Hunan provinces respectively,the chemical pattern characters of the volatile chemical constituents in Artemisia capillaris herba were characterized comprehensively from commonness,diversity and integrity.It showed a fair consistency in their GC-MS fingerprints among Artemisia capillaris herba samples from different sources.Artemisia capillaris herba was distinguished from Artemisia sacrorum L., a possible substitute in traditional Chinese medicine,by comparing the fingerprints with each other.
    Preparation and Binding Characteristic of a Morin-imprinted Polymer and Its Application to Thin Layer Chromatography Stationary Phase
    XU Zhi-Feng, LIU Lan, HE Jian-Feng, DENG Qin-Ying
    2005, 26(11):  2031-2036. 
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    A series of Morin-imprinted polymers were prepared and their adsorption properties for the template were evaluated by binding experiments.The results show that the polymer prepared by using acrylamide as the functional monomer,CH3CO2Et as the porogen exhibited a higher selectivity for Morin and good affinity to its structural analogues.The molar ratio of template to functional monomer in the pre-polymeric mixture was optimized.Scatchard analysis shows that a equal class of binding sites were formed in the imprinted polymer in the studied concentration range.The dissociation constant and the apparent maximum number of the binding sites were 0.877 mmol/L and 59.18 μmol/g,respectively.The function of the functional groups of the template in the formation of complementary interacting site in the polymer was discussed.It was concluded that the hydrogen bonds formed between the C-3—OH,C-7—OH,C-4'—OH of Morin and acrylamide played an important role in molecular recognition.Using the Morin-imprinted polymers as thin layer chromatographic stationary phase can separate the template from the other compounds.The minimal value of R-s to its structural analogue compound was 1.19.
    Performance Evaluation of Home-made Glass Microfluidic Glass Chips
    WANG Hui, HUANG Huai-Qing, DAI Zhong-Peng, GAO Yan, MA Bo, WANG Li, BAI Ji-Ling, LIN Bing-Cheng
    2005, 26(11):  2037-2039. 
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    Glass microchips with different structures and functions were fabricated in our laboratory.The basic characteristic of the home-made microchips was evaluated,such as the quality of the etched microchannels,reproducibility of electrophoretic separation,and life time etc..The migration time RSD for Rhodamine B in the same or different microchannels were 2.31% or 2.44%,respectively.The column efficiency in the same glass microchip didn't declined obviously until 200 consecutive running.Compared to the glass microchip made by Micralyne,the similar separation results were obtained on both kinds of microchips.Since,the cost of the home-made glass microchips is much lower, our home-made glass microchips show a great advantage(over) the commercial microchips in terms of the performance to cost.
    Surface Properties of Zirconia-based Supports for HPLC
    DUN Hui-Juan, WEI Yu, SONG Xiu-Qin, CHEN Li-Ren
    2005, 26(11):  2040-2042. 
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    The surface properties of zirconia-based supports,ZrO2/SiO2 and ZrO2,were compared.ZrO2/SiO2 prepared by layer-by-layer self-assembly(LbL SA) technique showed more favorable characteristics for HPLC applications compared with ZrO2 prepared by modified oil-emulsion method.The specific surface area and pore volume of ZrO2/SiO2 were about 18 and 20 times of those of ZrO2 respectively.The pore of ZrO2/SiO2 support was ideal cylindrical shape,but ZrO2 support had some \!ink bottle\" shaped-pores which was unfavorable for HPLC separations.Pore size distribution of ZrO2/SiO2 supports was more uniform than that of ZrO2 supports.
    Adsorption Behavior of Pb(2+) by Organic Components of Natural Biofilms in Natural Water and the Influencing Factors
    KANG Chun-Li, GUO Jing, GUO Ping, ZHAO Yu-Xia, DONG De-Ming
    2005, 26(11):  2043-2045. 
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    The biosorption of Pb2+ by the organic components(exopolymer,nonliving body bacterium and living bacterium) on the dominant bacterium obtained from the surface coatings in natural waters and the effects of biosorption time,temperature and initial pH were investigated.The results showed that Pb2+ biosorption process by the organic components above was divided into fast phase and slow phase,biosorption equilibrium time was 360,120 and 150 min respectively;the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium,the maximum biosorption amount of Pb2+ was all reached at pH=6,the effect of temperature on the biosorption ability of nonliving body bacterium and living body bacterium was negligible;both the Longmuir and Freundlish could describe the course of the biosorption of on Pb2+ by the organic components.the biosorption ability of exopolymer is much higher than nonliving body bacterium and living body bacterium;the thermodynamics experiments also carried on when the Cd2+ was present,the biosorption of Pb2+ by the three organic components was also followed the Langmuir and Freundlich(equation),but the biosorption amount and the saturated biosorption amount of Pb2+ was decreased.
    Synthesis and Biologic Activities of Glycerothiophospholipid Conjugate of Tegafur Containing Aryl-selenium Group in the Glycerol Skeleton
    ZHANG Qiu-Lin, ZENG Ji-Chao., XU Xin-Hua, ZHOU Bing, LU Rui-Liang, CHEN Xiong, LI Yan-Jie
    2005, 26(11):  2046-2051. 
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    2-Phthalimidoethyl-2-sulfur-1,3,2-dioxaphopholane(1) and cyclic glycerothiophospholipid conjugate of phahalimidoethanol(2) were used as model compounds to investigate the selectivity and reaction conditions of nucleophilic opening ring by heteroatomic function groups.CH3OH could attack the phosphor atom in 1,3,2-dioxaphopholane of compiound(1) to give O-methyl O-hydroxyethyl-O-phthalimidoethyl thiophosphate in 85% yield;in the presence of potassium hydroxide aryl selenol could attack the carbon atom in 1,3,2-dioxaphopholane of the cyclic phospholipid conjugate of N1-(2-furanidyl)-N3-(hydroxyalkyl)-5-fluorouracil to give the corresponding product of ring-opening in high yields.It was indicated through in vitro biological assays by using MTT that the title compound exhibited higher inhibitory effect on the malignant proliferation of bladder cancer cell T-24 and stomach cancer cell BGC-823 than tegafur,but on the other hand it showed a higher toxicity on the normal liver epithelial cell L-02.
    EPR Study on Regioselective Hydrogen Abstraction from p-Substituted Benzaldehydes by“Magic Blue”──The Generation of Perfluoro[(1-propoxyl)ethyl]p-Substituted Benzoyl Nitrooxides andthe Correlation Analyses of TheirαN,αFβValues with Substituent C
    LI Jin, LIN Zheng-Huan, DOUHong-Yan, ZHAO Cheng-Xue
    2005, 26(11):  2052-2056. 
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    New“magic blue”reagent containing bis(perfluoroalkyl) nitrooxide [n-C3F7OCF(CF3)]2.N(O.)(1) and perfluoronitrosoalkanen-C3F7OCF(CF3) NO2 in F113(CCl2FCClF2) solution whichwere both generated in the reaction of perfluoro[(2-propoxy)propyonyl] peroxide(n-C3F7OCF(CF3)COO)2with NaNO2,reacted with a series ofp-substituted benzaldehydes(3)viaregioselective abstraction of the for-myl hydrogen followed with spin trapping ofp-substituted benzoyl radical leading to the stable adducts perflu-oroalkylp-substituted benzoyl nitrooxides4.The correlation analyses ofαNandαβFwith all kinds of Hammettpolar and spin delocalization substituent constants disclose that the polar factor is the major factor varying spindensity on the nitrogen atom of the nitrooxides though the spin delocalization affects theαNvalue slightly.
    New Constituents from Eleutherine americana
    QIU Feng, XU Jin-Zhong, DUAN Wen-Juan, QU Ge-Xia, WANG Nai-Li, YAO Xin-Sheng
    2005, 26(11):  2057-2060. 
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    Three new constituents were isolated from Eleutherine americana Merr.et K.Heyne(Hong-cong)by means of silica gel,ODS column chromatography and high performance liquid chromatography(HPLC).They were identified as 9,9'-dihydroxy-8,8'- dimethoxy-1,1'-methyl-1H,1H'-\bi\funanyl]-3,3'-dione(1),6,8-dihydroxy-3,4-dimethoxy-1-methyl-anthraquinone-2-carboxylic acid methyl ester(2),2-acetyl-3,6,8-trihydroxy-1-methylanthraquinone(3) by physico-chemical propeties and spectral data,respectively.All three compounds showed weak activities against the growth of Pyricularia oryzae.The MMDC(Minimum morphological deformation mass concentration) was 145.8,50.2,124.8 μg/mL.Additionally,compound 2 also inhibited the proliferation of K562(human erythroleukemia) with IC50 value of 49.1 μg/mL.
    Expression and Identification of SARS-CoV Nucleocapsid Protein
    ZHAO Bo, JIN Ning-Yi, WANG Rui-Lin, ZHENG Min, ZHANG Ying-Jiu
    2005, 26(11):  2061-2065. 
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    According to the data in genebank and the characterization of the codon usage in yeast,the optimized gene encoding SARS nucleocapsid protein(1 296 bp) by mutating low-usage codon into synonymous ones was synthesized.After recombined with the CTL epitope gene(195 bp),the gene was cloned into secreted expression vector pPIC9K to pPIC9K-N.pPIC9K-N was transformed into the Pichia pastoris GS115,and then the positive recombinant GS115/pPIC9K-N was screened by MM and MD plates and identified by PCR further.Nucleocapsid protein was highly expressed with a yield of 20% as a secretion under methanol induction and the expressed nucleocapsid protein was isolated and purified by salting out.SDS-PAGE and Western blotting results showed that both the expressed and purified nucleocapsid protein were recognized specifically by SARS antiserum,showed good reactiongenicity and antigenic specificity.
    Concentration Variation of Middle Molecules in Sera of Chronic Renal Failure Patients and Inhibition for Na,K-ATPase
    YANG Mei, CHU Jie-Gen, ZHANG Jian-Da, YUAN Zhi, YANG Hong-Tao, LIU Hong-Fu, ZHAO Jing-Li, YANG Shu-Fen
    2005, 26(11):  2066-2068. 
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    Sera from patients with different courses of chronic renal failure and healthy persons were separated by gel permeation chromatography,and the concentration of middle molecular fraction B were calculated.The concentration of fractions B was increasing with the aggravating of renal failure degree,which indicated that the concentration of fraction B was related to patient's renal failure.Fractions B from uremic urine,uremic sera or normal urine were resolved into 10 to 17 sub-fractions by ion exchange chromatography.Sub-fractions from normal urine and from uremic sera were assayed for their inhibition for the activity of Na,K-ATPase.The results showed that the Na,K-ATPase activities of the samples with B-8 and B-9 were much lower than that of blank.It is indicated that B-8 and B-9 contained some compounds which could inhibit the activity of Na,K-ATPase.
    Measurement of Diffusion Coefficients of Three Aromatic Solvents at Infinite Dilution in Low Density Polyethylene Membrane Material
    JIANG Zhen, LI Ji-Ding, ZHAO Zhi-Ping, CHEN Cui-Xian, YU Hong-Wei, ZHANG Zhi-Hua
    2005, 26(11):  2069-2072. 
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    The retention time and the peak widths at half-height of benzene,toluene and ethylbenzene in the stationary phase of low density polyethylene were obtained by using gas chromatography.The diffusion coefficients of the small molecule solvents at infinite dilution were calculated with van Deemter equation.The graphs plotted according to the results of the diffusion coefficients of the three aromatic solvents at infinite dilution vs.temperatures were in agreement with the Arrhenius equation.The variance in the diffusion coefficients at infinite dilution of three aromatic solvents was analyzed according to the differences in molecular mass.
    Effects of Methanol Contaminant in Electrolyte on Performance of Graphite Electrodes for Li-ion Batteries Studied via Electrochemical Impedance Spectroscopy
    ZHUANG Quan-Chao, CHEN Zuo-Feng, DONG Quan-Feng, , JIANG Yan-Xia, ZHOU Zhi-You, SUN Shi-Gang
    2005, 26(11):  2073-2076. 
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    Electrochemical performance of graphite electrode cycled vs.Li in 1 mol/L LiPF6-EC/DEC/DMC(1:1:1, volume ratio) electrolyte solution,which contains different concentrations of methanol,was investigated by cyclic voltammetry and electrochemical impedance spectroscopy(EIS) in the process of first lithiation.It was demonstrated that methanol contaminant caused the deterioration of the electrochemical performance of graphite electrodes,which depends markedly on the concentration of methanol.Based on the experimental results and analysis,a mechanism of the deterioration of the electrochemical performance of graphite electrode caused by methanol contaminant was proposed.The methanol was reduced to lithium methoxide,that deposited on graphite electrode surface to form initial SEI(solid electrolyte interphase) near 2.0 V,which resulted in ethylene carbonate excess decomposition and poor passive ability of the SEI ultimately formed.
    Statistical Mechanics and Reaction Dynamics Theory for Polycondensations
    WANG Hai-Jun, HONG Xiao-Zhong, BA Xin-Wu
    2005, 26(11):  2077-2081. 
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    By the investigations of two types of representative polycondensations from statistical theory and dynamics,the relationship between the dynamics and statistics of the system under consideration is pointed out.Based on this,we obtain the explicit relationship between the conversions and equilibrium dynamical constant and reaction free energy,by which the characterization of the average polymer physical quantities can further be simplified.Moreover,the influences of temperature and pressure on the polymerization process are discussed.
    Application of ABEEM-σπ Model to Stereoselectivity in Classical Diels-Alder Reactions
    LI Ming-Nan, YANG Zhong-Zhi
    2005, 26(11):  2082-2085. 
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    Diels-Alder reaction has a huge application value due to their high stereoselectivity.The reactive region of this kind of cycloaddition includes not only atoms but also the important π bond zones.In this article,we utilized the ABEEM-σπ model to research this kind of reactions,and through the regional softnesses of both the atoms and π bonds,which were calculated by this model,we interpret properly the stereoselectivity of the typical Diels-Alder reaction.
    Monte Carlo Solution of Particle Size Distribution under Simultaneous Coagulation and Nucleation
    ZHENG Chu-Guang, ZHAO Hai-Bo
    2005, 26(11):  2086-2089. 
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    Particle size distribution evolves with time undergoing both particle coagulation and nucleation process.There are some difficulties for popular Monte Carlo(MC) methods to solve general dynamic equation(GDE) for simultaneous coagulation and nucleation of particle.A new multi-Monte Carlo(MMC) method was promoted to describe the time evolution of particle size distribution. MMC method is based on "time-driven" technique and introduces the concept of "weighted fictitious particle".Furthermore,MMC keeps synchronously the computational domain and the total number of fictitious particles constant.MMC method was used to simulate the time evolution of particle size distribution for constant coagulation kernel and the first-order nucleation kernel.The simulation results obtained by MMC method are in good agreement with numerical solutions,which proves that MMC method has a high and stable computational precision.In addition,MMC method has a low computation cost because the number of those tracked fictitious particles in MMC method is far less than that of the real particles.
    Preparation of AgcoreAushell Composite Bimetallic Nanoparticles and Its Surface-enhanced Raman Spectroscopy
    CUI Yan, GU Ren-Ao
    2005, 26(11):  2090-2092. 
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    AgcoreAushell bimetallic nanoparticles in the size range of 50—70 nm were prepared by reduction of AuCl-4 in the presence of prepared Ag nanoparticles.The composition of Ag100-xAu-x nanoparticles was varied from x=0 to x=30.The obtained nanoparticles were characterized by UV-Vis and TEM.Moreover,the activity of these nanoparticles in surface enhanced Raman spectroscopy(SERS) was checked by using p-aminothiophenol(PATP) as an adsorbate probe.It was found that the SERS signal intensity is dependent upon the n(Ag):n(Au) of these core-shell nanoparticles,as the Au fractions increased,the activity was enhanced first and then weakened,with the maximum intensity ten times stronger than Ag nanoparticles.
    Structure and Electrochemical Properties of LiFePO4 as the Cathode of Lithium Ion Battery
    LU Jun-Biao, TANG Zi-Long, LE Bin, ZHANG Zhong-Tai, SHEN Wan-Ci
    2005, 26(11):  2093-2096. 
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    Oliver phase LiFePO4 powder was successfully synthesized by solid-state reaction process and spherical processing.SEM observation confirmed that the resulatant product consisted of many spherical aggregates with diameters of 10—15 μm.The cyclic voltammetric profile of battery with cathode of LiFePO4 shows the single and reversible mechanism for lithium ion extraction/insertion in cathode.The a.c.impedance spectra of the battery at different temperatures reveal that the electrochemical impedance of battery decreases with increasing ambient temperature.At the current density of 17 mA/cm2,the batteries show a flat working voltage,little electrode polarity effect and nearly theoretical capacity.Below the current density of 170 mA/cm2,the high capacity is kept.With the current density increasing further above 170 mA/cm2,the capacity decreases fast and the electrode polarity effect is observed obviously.After cycling at a high current density,the batteries still show the high capacity at the low current density.
    Mass Transfer Process of CO2 Absorption Through Non-porous Hollow Fibre Contactor
    SUN Cheng-Gui, CAO Yi-Ming, ZUO Li, LIN Bin, JIE Xing-Ming, YUAN Quan
    2005, 26(11):  2097-2102. 
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    A non-porous hollow fiber contactor containing silicone rubber-polysulphone hollow fiber composite membranes is used for the absorption of CO2.The effects of various absorbents,liquid volumetric velocity,liquid pressure,concentration of NaOH solution and gas pressure on the efficiency of CO2 absorption are investigated.The experiment results indicate that the chemical absorption has a higher absorption efficiency than the physical absorption does and the membrane resistance controls the mass transfer accompanied by chemical absorption.Furthermore,when 2×103 mol/m3 NaOH solution is employed as the Absorbent,the overall mass transfer coefficient(5.21×10-6 mol·m-2·s-1·kPa-1) almost reaches the value of permeation without absorption(5.85×10-6 mol·m-2·s-1·kPa-1),and non-porous hollow fiber contactor has a higher selectivity for the existence of liquid film.Finally,the smooth mass transfer process shows that non-porous hollow fiber composite membrane eliminates bubbling and weeping in the liquid phase,which are frequently encountered in microporous hollow fiber contactor.Therefore,non-porous hollow fiber contactor used in this experiment has a potential for using as a gas-liquid contactor.
    Effect of La3+ Substituting Ba2+ on the Structure and Methane Combustion Activity of Ba1-xLaxMn3Al9O19-α Catalysts
    XU Jin-Guang, TIAN Zhi-Jian, ZHANG Pei-Qing, QU Xiu-Hua, XU Yun-Peng, XU Zhu-Sheng, LIN Li-Wu
    2005, 26(11):  2103-2107. 
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    Mn-substituted hexaaluminate(Ba1-xLaxMn3Al9O19-α) catalysts were prepared by hydrothermal synthesis based on hydrolysis of urea.Effect of La3+ substituting Ba2+ on phase compositions,structure,thermal stability and methane combustion activity was investigated.When x≥0.4,La2(CO3)3 decomposed in the range of 530—580 ℃ to be converted into La2O3.La2O3 reacted with γ-Al2O3 to form LaAlO3 perovskite phase in the temperature range of 800—900 ℃.BaAl2O4 spinel phase was suppressed due to the formation(of LaAlO)3perovskite phase,and higher dispersing of Ba2+ in the solid phase was maintained,which is(more favorable) for the formation of hexaaluminate phase.When(x<0.4),the BET specific surface areas(and methane) combustion activities of the Ba1-xLaxMn3Al9O19-α catalysts decreased due to the formation of(BaAl2O)4(spinel phase).The hexaaluminate structure distorted to some extent when Ba2+ were substituted with La3+.(The larger) the distortion,the lower the thermal stability of the Ba1-xLaxMn3Al9O19-α catalysts.The methane combustion activity of the Ba1-xLaxMn3Al9O19-α catalysts varied with the change of x,and the(Ba0.2La0.8Mn3Al9O)19-α((x=0.8)) catalyst showed the highest activity for methane combustion.
    Influence of Synthesis Method on Structure and Catalytic Performance of MCM-22 Zeolites
    YANG Piao-Ping, WANG Zhen-Lü, YU Jian-Feng, XU Ning, LIU Qing-Sheng, SU Mei-Ping, WU Tong-Hao
    2005, 26(11):  2108-2112. 
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    Pure MCM-22 with a high crystalline was hydrothermally synthesized by dynamic and static(methods,) respectively.The influence of the synthesis conditions on the structure and properties of MCM-22 was studied by means of N2 adsorption,XRD,TEM and FTIR. MCM-22 synthesized by dynamic method shows much smaller crystal and lower concentration of acid sites than those of synthesized by static method.The Pd-supported catalyst on MCM-22 synthesized by static method shows a higher acetone conversion than that prepared by dynamic method in one-step synthesis of methyl isobutyl ketone(MIBK) from acetone.We attributed this to the higher concentration of acid sites of MCM-22 synthesized by static method.While the selectivity to MIBK exhibited an adverse trend,this might be due to shorter distance of the channel,which decreased the contact time of the reactants in the channels.As a result,the selectivities of the further condensation and hydrogenation products decreased.
    Molecular Simulation of Equilibrium Adsorption of Nitrogen and Oxygen both in Slit Pore and on Membrane Surface
    WANG Shu-Mei, GAO Guang-Hua, YU Yang-Xin, WANG Xiao-Lin
    2005, 26(11):  2113-2116. 
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    Monte Carlo molecular simulation is employed to investigate the equilibrium adsorption of nitrogen and oxygen in the slit pore and on the carbon membrane surface.The interactions among all kinds of molecules are modeled with Shifted-Lennard-Jones potential.The results obtained display the oxygen density distribution both in the slit pore and on the membrane surface varying with the change of pore width and membrane length at 303 K and 10 MPa.The excess adsorption isotherms(which measure the increased density in the slit pore,relative to that of the bulk fluid) per unit volume of both nitrogen and oxygen at 303 K show a maximum at a particular value of the pressure.The principal conclusions of this work are as follows:(1) the entrance-pore effect on the density distribution of gas in the slit pore is distinct;(2) the excess adsorption in the pore increases with the decrease of slit pore width;(3) the membrane model plays a significant role in the excess adsorption on the membrane surface.
    Preparation and Electrochemical Performance of a Novel Lithium Battery Cathode Material Polysulfurpolyaniline
    YUAN Ke-Guo, WANG An-Bang, CAO Gao-Ping, YANG Yu-Sheng
    2005, 26(11):  2117-2121. 
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    A novel cathode material containing S-S side group on the main polyaniline chain backbone was obtained for lithium secondary battery.Polychloropolyaniline and polysulfurpolyaniline were prepared successively by the reactions of polyaniline with chloride monosulfur catalyzed by AlCl3 and with Na2S5,respectively.The resultants were both analyzed by elemental analysis, IR spectroscopy,X-ray electron spectroscopy(XPS) and SEM.XPS data suggested that electrons were more localized in the monomers of the main polyaniline chain structure of polysulfurpolyaniline.The polyaniline chain structure of polysulfurpolyaniline couldn't effectively catalyze the electrochemical reaction of side group S-S.The charge-discharge profile and the corresponding differential profile indicated that the charge-discharge process maybe contained three successive redox reactions,and there was an obvious discharge voltage plateau at 2.07 V.The discharge specific capacity of polysulfurpolyaniline was in the range of 181-187 mA·h/g and the efficiency was up to 94% for 30 charge-discharge cycles.
    Influence of Distributed Delay on Turing Pattern Formation in Coupled Reaction Diffusion Systems
    JI Lin, , ZHANG Zhong-Xian, GAO Feng-Xin, LI Qian-Shu
    2005, 26(11):  2122-2124. 
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    The influence of distributed delay coupling on Turing pattern in reaction diffusion system was investigated. Numerical-simulation results proved that the distributed delay of the coupling can significantly influence the spatiotemporal property,even the stable dynamic of the system.The local distributed coupling can spatially orient the pattern at an appropriate coupling strength.
    Periodic Ab initio Calculations on Ag+ and Cu+ Azides
    JU Xue-Hai, JI Guang-Fu, QIU Ling, XIAO He-Ming
    2005, 26(11):  2125-2127. 
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    The energy bands,electronic structures of CuN3 and AgN3 crystallines were investigated by periodic ab initio method.The charge density projection shows that there are overlaps of isodensities between the terminal nitrogen and metallic ion,indicating that the metals and the azides are combined by covalent bonds.The crystal lattice energies are-781.05 and-840.83 kJ/mol for CuN3 and AgN3 respectively.These results approach the data obtained by Gray's approximate method.The frontier crystal orbital mainly consists of the atomic orbital of azide's terminal nitrogen.The energy gap for AgN3 is smaller than that of CuN3,and the highest occupied crystal orbitals of AgN3 consist of both the atomic orbitals of the terminal nitrogen in azide and the silver ion,which facilitates the electron to leap from terminal nitrogen in azide to metallic ion directly.Hence silver azide is slightly more sensitive than copper azide.The elastic coefficients C11,C22 and C33 of CuN3 are predicted to be 96.52,96.86 and 154.06 GPa,C11 and C22 of AgN3 are 303.29 and 138.80 GPa.
    Transfer Enthalpies of Glycine from Water to Aqueous Organic Solutions
    MA Lin, LIN Rui-Sen, LIN Gui-Mei, XUNan
    2005, 26(11):  2128-2130. 
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    The enthalpies of solution of glycine in aqueous solutions of urea,formamide,acetamide,DMSOand acetone were measured at298.15 K by a RD496-Ⅲ microcalorimeter.The transfer enthalpies(ΔtrH) ofglycine from water to aqueous organic mixtures were derived and interpreted qualitatively with structural hydra-tion interaction model.The results suggest that hydrophilic-hydrophilic interaction between glycine and cosol-vent molecule gives a negative contribution to the transfer enthalpies of glycine,while the hydrophilic hydro-phobic interaction makes a positive contribution.The relative position ofΔtrH-composition profiles viz.urea <formamide <0 <acetamide <DMSO<acetone,characterizes the hydrophobicity or hydrophilicity of the cosol-vent molecule and correctly reflectes the solute-solvent interaction in the transfer process.
    Magnetic-field-induced Alignment of Metal Nanoparticles in Polymer──Experiments and Molecular Dynamics Simulation
    ZHANG Bang-Wen, XIE Chang-Sheng, HU Jun-Hui, WANG Hui-Hu, GUI Yang-Hai
    2005, 26(11):  2131-2134. 
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    A one-dimensional ordered nanocomposite was fabricated by utilizing magnetic field to control the alignment of carbon-coated nickel(Ni@C) nanoparticles in epoxy resin.It exhibits an excellent improvement in electrical conductance and dielectric constant.With the loading mass fraction of 3%—10%,the resistivity of resulting composite decreases by 3 orders of magnitude with respect to unaligned composite.A molecular dynamics model was designed to simulate the structure evolution of nanoparticles in resin curing.The simulated results show that the alignment of nanoparticles arises from the dominant magnetic dipolar interaction,and experiences a shift from aggregation to chaining then to chain thickening;the time scale for chain growth is the order of seconds,there is nearly not dynamics barrier for the alignment of Ni@C nanoparticles in epoxy resin;the simulated structure agrees basically with those observed in experiments.
    Photo-oxidation Degradation and Depth Profiles of Polyethylene-CaCO3 Composites
    YANG Rui, YU Jian, WANG Kun-Hua, LIU Ying, SHONG Yuan-Yuan, WANG Hong-Kai
    2005, 26(11):  2135-2139. 
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    Inorganic fillers are widely used in polyolefin modification in order to improve the strength and toughness,and cut down the cost as well.However, the effects of the fillers and the coupling agents on the photo-oxidation degradation of polyolefins were not studied throughly.The natural photo-oxidation degradations of HDPE(high density polyethylene)-CaCO3 composites were studied.The results show that the mass concentration of CaCO3 doesn't influence the oxidation degree of HDPE much,while the hydroxyl index of HDPE composite increases with the concentration of CaCO3.The coupling agents play different roles in the photo-oxidation degradation of HDPE-titanate can accelerate the oxidation of HDPE greatly,while other coupling agents have minor influences. In the samples with the thickness of about 3.2 mm,the depth profiles were investigated by infrared microscopy,and the section morphologies were observed as well.The crack length in the section of HDPE-CaCO3-titanate composite corresponds exactly to the transition point in the corresponding CI vs. depth curve.The addition of CaCO3 and its surface treatment with different coupling agents lower the crystallinities of HDPE greatly.From these demonstrations,a hypothesis may be proposed that the lower crystallinity of a composite permits the oxygen to diffuse further into the interior and supplies more surface areas for the oxidation reaction to occur,and,thus,results in the higher oxidation degree.
    Changes of Micromorphology and Ion Concentrations for Bioactive Composite Materials During the Process of Biomineralization under Physiological Condition
    ZHENG Yu-Dong, WANG Ying-Jun, YANG Huai, CHEN Xiao-Feng, CHEN Zhong-Hua, WU Gang, XIE Jian-Xin
    2005, 26(11):  2140-2144. 
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    Three kinds of bone tissue engineering scaffolds and bone repaired materials with excellent properties were prepared by using poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV) and bioactive glass(BG),tricalcium phosphate(TCP),hydroxyapatite(HA) compounds.The changes in surface micromorphology and ion concentration of reaction solution for the three kinds of composite materials were investigated and compared before and after soaking in simulated body fluid(SBF) solution.Results obtained in this work indicated that the biomineralization and ion exchange reaction and degradation occurred in PHBV/BG,PHBV/TCP and PHBV/HA composites in SBF solution,and mineralized layer formed on the surface of these composites which was proved as hydroxyl carbonate apatite(HCA).But the processes and grade of biomineralization were distinct for PHBV/BG,PHBV/TCP and PHBV/HA composites,the bioactivity of PHBV/BG was better than others.
    Synthesis and Characterization of Thermally Stable Sulfonated Polybenzimidazoles
    QING Sheng-Bo, HUANG Wei, YAN De-Yue
    2005, 26(11):  2145-2148. 
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    A series of sulfonated polybenzimidazoles(sPBI-IE) with various sulfonation levels was synthesized from 5-sulfoisophthalic acid monosodium salt,4,4'-dicarboxydiphenyl ether and 3,3'-diaminobenzidine by solution copolycondensation in poly(phosphoric acid).The resulting polymers with good solubilities in DMF,DMSO and DMAc were characterized by FTIR,1H NMR,GPC and TGA.The number average molecular weights of the sodium salt form sPBI-IE are 41 300—46 900,and the polydispersity indices are in the range of 2.15—2.54.The synthesized sPBI-IE presents excellent thermal stabilities,the onset decomposition temperature and the 5% and 10% weight loss temperatures are higher than 513, 573 and 597 ℃,respectively.
    Novel Proton Exchange Membranes Used for Fuel Cell──Sulfonated Poly(arylene ether sulfone) with tert-Butyl Groups
    WANG Zhe, , LI Xian-Feng, ZHAO Cheng-Ji, LU Hui, NI Zhuo, NA Hui, QIAN Ya-Qin
    2005, 26(11):  2149-2152. 
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    A novel series of sulfonated poly(arylene ether sulfone)s with various of sulfonation degrees were synthesized by nucleophilic displacement polycondensation of tert-butylhydroquione with different molar ratios of 4,4'-diflouorobenzophenone to 3,3'-disulfonate-4,4'-dichlorodiphenylsulfone in the presence of potassium carbonate in NMP.The structure and property of polymers were characterized and studied by FTIR,DSC and etc..They can be easily cast into tough membranes and show good mechanical and electrochemical properties.The polymers show good prospective usages in the proton exchange membranes fuel cell.
    Reverse ATRP of MMA Catalyzed by AIBN/SmCl3/Lactic Acid System
    XIONG Yu-Bing, FAN Ling, SHEN Zhi-Quan
    2005, 26(11):  2153-2156. 
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    Reverse ATRP of methyl methacrylate(MMA) mediated by AIBN/SmCl3/lactic acid system was investigated.The one electron transfer reaction of SmCl3 to SmCl2 was firstly employed for living/controlled radical polymerization successfully.The kinetics study indicates that the polymerization is first order in monomer concentration.Moreover,the number average molecular weight(M-n) increased linearly with the monomer conversion,and the molecular weight distributions were narrower(less than 1.5).These show that the polymerization of MMA is a living/controlled one in the above system.The effects of different reaction conditions,such as solvent sort,temperature and ratio of 0/0/0,on the polymerization were studied.PMMA with narrower molecular weight distribution were obtained in DMF at 80℃.Furthermore,the apparent activation energy E-app=74.1 kJ/mol was calculated for the reverse ATRP of MMA initiated by AIBN/SmCl3/lactic acid.
    Compatibilization of PES/NA-PAEK Polymer Blends
    JIANG Dong, CHEN Xing-Bo, NIU Ya-Ming, ZHANG Yun-He, JIANG Zhen-Hua, MA Rong-Tang
    2005, 26(11):  2157-2159. 
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    4,4'-Dihydroxyldiphenylsulfone-poly(aryl ether ketone)s containing 1,4-naphthalene was synthesized by 1,4-bis(4-fluorobenzoly)naphthalene and 4,4'-dihydroxyldiphenylsulfone.The effect of the polymer,as a compatibilizer,on the tensile behavior,morphology and compatibility of PES/NA-PAEK blends was investigated.PES and NA-PAEK formed the structure of interlock by the addition of compatibilizer.The compatibility and tensile properties of blends were improved.
    Synthesis and Characterization of Injectable Supramolecular Structured Hydrogels Prepared by Free Radical Polymerization of PLA-b-PEG-b-PLA Macromers and α-Cyclodextrins
    ZHU Kai-Qiang, WEI Hong-Liang, HE Ji-Yu, QIAN Li-Jun, HOU Dan-Dan, ZHANG Ai-Ying, FENG Zeng-Guo
    2005, 26(11):  2160-2164. 
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    Poly(L-lactide)-poly(ethylene glycol)-poly(L-lactide) triblock copolymer(PLA-PEG-PLA) was synthesized by the ring-opening polymerization of L-lactide with poly(ethylene glycol)(PEG6000) as the initiator and Sn(Oct)-2 as the catalyst in toluene.This copolymer was further reacted with methacrylic anhydride to give a soluble macromer terminated with methacryloyl groups.Two kinds of supramolecular structured hydrogels were obtained through mixing the macromer with α-cyclodextrins and then initiating by using ammonium persulphate with ascorbic acid or ferrous sulfate.The macromer and hydrogels were characterized by 1H NMR,FTIR,TGA and XRD etc..Based on rheological test,the two kinds of the resultant hydrogels are injectable with appropriate pot-life.
    Synthesis and Perporties of Novel Gel Polymer Electrolyte
    QI Li, DONG Shao-Jun
    2005, 26(11):  2165-2169. 
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    The copolymer acrylonitrile-methyl methacrylate-poly(ethylene glycol)methyl ether methacrylate and its comb-like gel polymer electrolyte were designed and synthesized.The results indicate that the comb-like copolymers with different component ratios have two glass transfer temperatures,one is the main chain's(about 30—60 ℃),the other is side chain's(between-50——30 ℃).The heat stability of the comb-like copolymer changes with variation of the ratios of acrylonitrile.And the copolymer can be used at 150 ℃.The comb-like gel polymer electrolyte takes advantages of acrylonitrile and poly(ethylene oxide). Its mechanical perporties is very good.And the conductivity of the comb-like gel polymer electrolytes is in the magnitude range of 103 S/cm at room temperature.The electrolyte has a value of practical application.
    Preparation of PAM-ZnS Hybrid Microspheres with Core-Shell Structures
    ZHANG Dan, SONG Xi-Ming, LIANG Fu-Xin, ZHANG Guo-Lin, ZHANG Jian-Jun, LI Ying, LIU Feng-Qi
    2005, 26(11):  2170-2172. 
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    PAM-ZnS hybrid microspheres with diameters of 640-660 nm were fabricated in two simple steps: the formation of polyacrylamide(PAM) microspheres via the polymerization of acrylamide in the water phase of a water-in-toluene emulsion,and the sedimentation of ZnS at the inside or on the surface of the PAM microspheres in the emulsion via the reaction of Zn(AC)2 and Na2S or H2S.ZnS@PAM and PAM@ZnS hybrid microspheres were obtained by the use of Na2S and H2S as the precipitating agent respectively.The hybrid microspheres were characterized with TEM and FTIR spectrum.The XRD results show that ZnS in the hybrid microspheres is in a crystalline state with a face-centered structure.The hybrid microspheres are photoluminescence-active due to the presence of ZnS.
    Synthesis of Polyacrylamide/α-Zirconium Phosphate Nanocomposite by in-situ Intercalative Polymerization and the Characterization of Its Structure
    ZHANG Rui, HU Yuan, WANG Shi-Long
    2005, 26(11):  2173-2175. 
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    The polyacrylamide(PAM)/α-zirconium phosphate(α-ZrP) nanocomposite was synthesized by in situ intercalative polymerization of acrylamide monomer with α-ZrP exfoliated by methylamine.Its structure and morphology were characterized by X-ray diffraction(XRD) and transmission electron microscopy(TEM).The results demonstrated that the interlayer distance of α-ZrP was expanded effectively after the polymerization of acrylamide,even forming exfoliated nanocomposite.Both XRD and TEM image confirmed that the most of the layers of α-ZrP were dispersed well in the polymer matrix,and the PAM/α-ZrP intercalated nanocomposite with the d-spacing of about 1.5 nm can be obtained at a high loading of α-ZrP(mass fraction ≥10%).At the same time,some of the layers of α-ZrP were exfoliated and dispersed disorderly in the PMA matrix.
    Synthesis and Characterization of High Molecular Weight Polyaniline/MWNTs Composites
    CHAO Dan-Ming, CHEN Jing-Yu, LU Xiao-Feng, CHEN Liang, ZHANG Wan-Jin
    2005, 26(11):  2176-2178. 
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    Composites of high molecular weight polyaniline with various weight percentages of multi-walled carbon nanotubes(MWNTs) were synthesized in the presence of selected dissolved neutral salt by in situ polymerization.The composites were characterized by means of SEM,FTIR and XRD,four-point probe conductivity measurements.The results indicate that the composites possess very different morphologies,high electrical conductivities and good crystallization compared with high molecular weight polyaniline.
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