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Table of Content

    24 February 2002, Volume 23 Issue 2
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    Articles
    Synthesis of 2-(p-Propenoyloxyphenyl)-5,10,15,20- tetraphenylporphyrin Nickel Polymer
    LI Ping-Ying, HUANG Qi-Mao, CHEN Zhang-Ping, MA Shu-Yi, Xu Han-Sheng
    2002, 23(2):  173-175. 
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    2-(p-propenoyloxyphenyl)-5,10,15,20-tetraphenylporphyrin nickel(Ⅱ) and 2-(o-propenoy-loxyphenyl)-5,10,15,20-tetraphenylporphyrin nickel(Ⅱ′) was synthesized from acryoyl chloride with 2 (p hydroxyphenyl)5,10,15,20 tetraphenylporphyrin nickel(Ⅰ) and 2-(o-hydroxyphenyl)-5,10,15,20-tetraphenylporphyrin nickel(Ⅰ′) correspondingly. Compound (Ⅱ) was further polymerized to 2-(p-propenoyloxyphenyl)-5,10,15,20-tetraphenylporphyrin nickel(Ⅲ) in the presence of initiator. Their chemical structures were identified by NMR, UV-Vis, IR and MS spectra, as well as elemental analysis.
    γ-Irradiation Route to Prepare Silver Sulfide Nanocrystals
    NI Yong-Hong, GE Xue-Wu, LIU Hua-Rong, ZHANG Zhi-Cheng, YE Qiang, WANG Feng
    2002, 23(2):  176-178. 
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    Silver sulfide nanocrystals were successfully prepared by γ-irradiation in water and ethanol systems, respectively, at an ambient pressure and room temperature. Sodium thiosulfate, thiourea and carbon disulfide were employed as the sulfur ion source. The products were characterized by some means including X-ray powder diffraction(XRD) , transmission electron microscopy(TEM) and X-ray photoelectron energy spectrum(XPS). The result of the experiments indicated that the kind of the solvent and the sulfur ion source had influence on the size of silver sulfide nanoparticles. An interesting phenomenon was found in the TEMimage of sampleⅡ: several long rods existed in the product and a tubular structure could be seen in one of these rods. The formation of this kind of special structure could be relevant to the coordination between thiourea and silver in water system.
    Preparation of LixMn2O4 Spinels by in-situ Redox Precipitation Hydrothermal Synthesis Process
    LIU Xing-Quan, CHEN Zhao-Yong, LI Shu-Hua, HE Ze-Zhen, YU Zuo-Long
    2002, 23(2):  179-181. 
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    LixMn2O4 spinels were prepared by in-situ redox precipitation hydrothermal synthesis method, and characterized by XRD, BET, TGA, TEMand SEMetc. , and the effects of many factors on the properties of as-prepared LixMn2O4 samples were investigated. The results demonstrated that LixMn2O4 spinels can be synthesized under milder conditions by in-situ redox precipitation hydrothermal synthesis method. LixMn2O4 spinels are cubic and symmetrical, and have a better stability at less than 700℃, their surface areas and particle sizes were strongly affected by crystallization temperature and time, pH value, calcination temperature and time. The optimal conditions of LixMn2O4 synthesis were determined as follows: the alkalinity(pHvalue) was 9; the crystallization temperature and time were more than 240 ℃ and 48 h, respectively; the calcination temperature and time were between 700-750 ℃ and 6-12 h, respectively; the molar ratio of Li to Mn was less than 1.2/2.
    Studies of the Coordination Reaction Between Aza-bridged Bis-phenanthroline Macrocycle and Metal Ion
    LIU Hai-Yang, HU Xi-Ming, YING Xiao, WU Ting-Wan, WANG Wen-Jwu, CHUANG Kuo-Shen, LUO Chi-Fong
    2002, 23(2):  182-184. 
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    Homogeneous solution of poor soluble aza-bridged bis-phenanthroline macrocyclic compound(H2HAPP) was obtained by adding K2CO3 to its trifluoroacetate in CH3OH-CH2Cl2[ V (CH3OH): V (CH2Cl2)= 1:1] solution. Coordination reaction between H2HAPPand metal ion Zn(Ⅱ) in CH3OH CH2Cl2[ V (CH3OH): V (CH2Cl2)=1:1] solvent was studied by UV-Vis spectroscopic method, which indicated 1:1 complexing between H2HAPP and Zn(II) ion occurred easily in such a homogeneous system at room temperature. And the formation of ZnHAPPcomplex was further confirmed by FAB MS and 1H NMR spectra.
    Synthesis and Crystal Structure of a Novel 2D Network Copper Complex Constructed Through Hydrogen Bonds Linking Zigzag Chains
    WANG Xin-Yi, LI Jun-Ran, LIU Qin-De, GAO Song, YU Kai-Bei
    2002, 23(2):  185-187. 
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    The aminocarboxylic acid, phenyliminodiacetic acid [C6H5N(CH2COOH)2, H2L] , was synthesized by the reaction between phenylid and chloroacetic acid. The copper complex with the acid [CuL(H2O)] was obtained in aquo solution and its crystal structure was determined by X-ray diffraction with a final R1 value of 0.0244 and a wR2 value of 0.0660. The crystal is of monoclinic system with a space group P21/C . The unit cell parameters are as follows: a =1.2183(2) nm, b =0.86831(10) nm, c= 0.97940 nm , β =96.100(10)°, V =1.0322(2) nm3, Z =4, Dc=1.862 g/cm3, F (000)=588, μ =2.129 mm-1 . In crystal, each copper ion is coordinated with three oxygen atoms and one nitrogen atom from H2L and an oxygen atom from water; the coordination polyhedron around Cu 2+ is a distorted tetragonal pyramid. Cu 2+ are linked by anti anti carboxyl bridges to form endless zigzag chain, a two dimensional network is obtained through the hydrogen bonds between the adjacent chains.
    Synthesis and Crystal Structure of Cyclopentylindene Rare Earth Complex (C5H9C9H6)3SmCl-Li+(THF)4
    CUI Dong-Mei, TANG Tao, CHENG Jian-Hua, HU Ning-Hai, CHEN Wen-Qi, HUANG Bao-Tong
    2002, 23(2):  188-190. 
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    Rare earth complex(C5H9C9H6)3SmCl-Li+(THF)4(Ⅰ) was synthesized by reacting anhydrous SmCl3 with two equivalents of C5H9C9H6Li. From mix solvent of THF and hexane, red color single crystals were obtained. The crystal belongs to a cubic system, space group P213 with unit cell parameters a=b=c =1.7540(2) nm, α=β=γ =90°, V =5.3964(11) nm3, Z =4. The ten-coordinated samarium atom is bonded to three cyclopentylindenyl rings and a chlorine atom to form the anionic part of the title complex, ring centroids and the chlorine atom form a tortured tetrahedron around samarium. In the cationic part, lithium atom coordinates to four oxygen atoms of THF molecules to form a normal tetrahedron. The Sm-C(within the same ring) distance varies from 0.268 to 0.299 nm.
    The Syntheses of New Hosts-thiazoleazo Calixarenes Derivatives and Its Application in Recognition Analysis of Heavy Metal Ions
    LÜ Jian-Quan, HE Xi-Wen
    2002, 23(2):  191-194. 
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    The synthesis of 5,11,17,23-tetrakis(2-thiazole)azo-25,26,27,28-tetrahydroxy calixarene(Ⅰ) and 5,11,17,23,29,35-hexa(2-thiazole)azo-37,38,39,40,41,42-hexahydroxy calixarene(Ⅱ) was described. The structures were confirmed by IR, 1H NMR and elemental analysis. It was found that the synthesized derivatives have a good solubility in basic aqueous medium and posses molecular binding properties. It was showed that the derivatives exhibit a high selectivity for Ag+, Hg2+ and other ions compared with Na+, K+ and NH4+, which is because metal ions such as Ag+ and Hg2+ display a great affinity for soft coordination center of nitrogen and sulfur atoms.
    Layer-by-Layer Assembly of Multilayer Films Composed of Streptavidin and Biotinylated Antibody by Real-time Biomolecular Interaction Analysis
    PEI Ren-Jun, CUI Xiao-Qiang, YANG Xiu-Rong, WANG Er-Kang
    2002, 23(2):  195-198. 
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    Layer-by-layer assembly of multilayer films of streptavidin and biotinylated antibody was completed on the streptavidin coated surface. Real-time biomolecular interaction analysis(BIA) based on surface plasmon resonance technique was used to monitor the multilayer assembly in solution continuously. The results indicate that the uniform multilayer film can be fabricated successfully based on the strong interaction between streptavidin and biotin. The mean surface mass concentration of each adsorption layer is 1.32 ng/mm2 for biotinylated antibody, 2.93 ng/mm2 for streptavidin, according to the correlation of SPRresponse with surface concentration.
    The Ephedrine and Pseudoephedrine Separation with the Capillary Electrophoresis and Determination by Conductivity Detector
    ZHENG Yi-Ning, XIE Tian-Yao, MO Jin-Yuan, WEI Shou-Lian
    2002, 23(2):  199-202. 
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    The separation between ephedrine and pseudoephedrine with capillary electrophoresis and determination by the conductivity detector is reported. The separation mechanism is studied and the determination method is found. The effects of complex reagent concentration, concentration and pHof the running buffer, separation voltage and the organic solvent concentration are investigated and discussed. At 13.5 kVhigh voltage the ephedrine and pseudoephedrine are separated successfully in a citric acid sodium citrate buffer(pH=4.5) with the copper salt as the complex reagent. Ethanol is used to improve the peak shapes and separation effects. There are an excellent linearity between peak area and concentration of analytes in the concentration range of 1.4-165 mg/Lfor ephedrine and 0.825-165 mg/Lfor pseudophedrine with the detection limits(S/N =3) of 0825 and 0198 for ephedrine and pseudophedrine respectively. Relative standard deviations(RSD) of the ephedrine and psudoephedrine are 32%(ephedrine) and 28%(psudoephedrine) based on the determination of seven times. The ephedrine and pseudoephedrine in collunarium are detected and the satisfaction results are obtained.
    Preparation and Characteristics of High Performance Affinity Chromatography Medium Used for the Separation of Antithrombin Ⅲ
    ZHAO Ying-Xin, SHANGGUAN Di-Hua, ZHAO Rui, LIU Guo-Quan
    2002, 23(2):  203-206. 
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    A high performance affinity chromatography medium used for separation of antithrombin Ⅲ was prepared. Monodisperse poly(glycidyl methacrylate) beads(PGMA) were employed as the affinity support. Heparin was linked covalently to amino-PGMA-beads, which was prepared by amination of PG-MA. The resultant affinity media present a minimal non specific interaction with proteins and the protein recovery was 96.9% and 94.4% for antithrombin Ⅲ and human serum albumin, respectively. Its affinity capacity for antithrombin Ⅲ was 12 mg/g beads. The apparent dissociation constant between antithrombin Ⅲ and immobilized heparin was 1.96×10-5 mol/Lwhich was evaluated by front chromatography. The affinity medium was used to separate antithrombin Ⅲ from human plasma.
    Studies on the Electrospray Ion Trap Mass Spectra of SFZ-47 and Its Metabolites for a Novel Anti-inflammatory and Analgesic Agent
    GU Jing-Kai, CHU Da-Feng, ZHONG Da-Fang, LI Yan, ZHOU Hui, SHEN Jia-Cong
    2002, 23(2):  207-209. 
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    To investigate the characteristics of mass spectra of 3H-1,2-dihydro-2-(4-methyl-phenylamino)methyl-1-pyrrolizinone(SFZ-47), a novel anti-inflammatory and analgesic agent, and its metabolites, urine samples, which were collected from healthy beagel dogs after a single dose of 200 mg SFZ-47 was taken, were analyzed using electrospray ion trap mass spectrometry in a multi-stage MS full scan mode. The mass spectrometry was operated in the positive mode. The obtained mass spectra were analyzed by assisting with the software Mass Frontier 1.0 for their fragmentation pathways. Besides SFZ-47, four of its metabolites were identified in the urine by LC/MS. The full scan MS2 or MS3 spectra of each compound gave characteristic fragment ions of m/z 122 and depyrrolizinone respectively, whereas the ions of dehydration and neutral loss 176 u of two glucuronides were also found. These characteristics can be used for the future structure elucidation in metabolism of SFZ-47 and its analogues.
    Chromatographic Properties of a Novel Shielded Bonded Stationary Phase for Liquid Chromatography
    JING Yu-Qing, LONG Yuan-De, HUANG Tian-Bao
    2002, 23(2):  210-212. 
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    A novel bonded stationary phase, octadecanamido imine bonded stationary phase(ODAI), for reversed-phase HPLC was prepared by bonding stearyl chloride to YWG-80 silica gel through 3-(2-aminoethylamino)propyltrimethoxysilane. Hydrophobicity, selectivity and silanophilic activity of ODAIphase were evaluated by using aromatic compounds as analytes and methanol-water as binary mobile phase. The organic components including acidic, basic, neutral aromatic analytes could be separated satisfactorily with an excellent selectivity and chromatographic peak shape. The asymmetry factors of basic aniline, o-toluidine and N,N-dimethylaniline were found to be 114, 106 and 101, respectively, using methanol-water(volume ratio is 55:45) as mobile phase. Aniline is eluted before phenol due to the internal masking interaction to suppress ion exchange activity of residual silanols.
    Nonpolar Monolithic Capillary Electrochromatographic Column Modified with Cationic Surfactants on CEC
    WU Ren-An, ZOU Han-Fa, YE Ming-Liang, LEI Zhen-Deng, NI Jian-Yi
    2002, 23(2):  213-215. 
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    A mode of capillary electrochromatography(CEC) based on the dynamical adsorption of an nonpolar monolithic stationary phases with a cationic surfactant, long chain quaternary ammonium slat of cetyltrimethylammonium bromide(CTAB) has been developed. The effects of pHvalue and the concentration of cetyltrimethylammonium bromide in mobile phase on electroosmotic mobility and the retention factors of solutes were investigated.
    Determination of Heparin with Basic Bisphenylnaphthylmethane Dyes by Fading Spectrophotometry
    XU Hong, LIU Shao-Pu, LUO Hong-Qun, LIU Zhong-Fang
    2002, 23(2):  216-218. 
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    A new spectrophotometric method for the determination of trace heparin has been studied. The method was based on the discoloration reaction between heparin and bisphenylnaphthylmethane dyes such as victoria blue 4R(VB4R), victoria blue B(VBB) and night blue(NB) in weak acid medium. The reduction in absorbance was directly proportional to the concentration of heparin. The linear ranges of heparin were from 0 to 2.4 μg/mLfor all systems. The molar absorptivities(ε) of the three systems were between 2.11×106 and 2.66×106L·mol-1 ·cm-1 and the sensitivity of VB4R system was the highest. Taking VB4Rsystem for an example, the effects of some coexisting substances on the determination of heparin have been investigated and the results showed that the method had a good selectivity. The method has been applied to determination of the heparin samples with satisfactory results.
    A Sensitive Indication of the Rigid Microenvironment of the Bile Salt Aggregate Room Temperature Phosphorescence Probe
    LIU Li-Hong, XIE Jian-Wei, ZHANG Shu-Zhen, JIN Wei-Jun
    2002, 23(2):  219-221. 
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    In this paper, we report the investigation of the interaction between room temperature phosphorescence(RTP) probe, α-bromonaphthalene(α-BrN), and a series of cholate surfactants using RTPspectroscopy. It was found that intense RTP of α-bromonaphthalene can only be induced in aqueous deoxycholate sodium(NaDC) solution. This observation showed that the interior structure of NaDC aggregate was more rigid and efficient in shielding the excited state of α-BrN from oxygen quenching. The experiments suggested that the more chiral separation capability of NaDCaggregate of could be due to its more rigid interior structure.
    Studies on the Reaction of Aromatic Aldehyde with Active Methylene Compound under Microwave Irradiation
    TU Shu-Jiang, DENG Xu, ZHOU Jian-Feng, SUN Bai-Wang, FENG Jun-Cai 
    2002, 23(2):  222-225. 
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    A series of 4-aryl-7,7-dimethyl-2, 5-dioxo-1,2,3,4,5,6,7,8-octahydroquinoline (4) and 4-aryl-7,7-dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin (5) were synthesized from aromatic aldehydes (1), 5,5-dimethyl-1,3-cyclohexandione (2) and isopropylidene malonate (3) by the condensation, addition, cyclization and elimination reactions under microwave irradiation under different conditions. The reactions were completed in 3-5 min with good yields. The structure of the products were established on IR, 1H NMR, elemental analysis and X-ray diffraction.
    Molecular Mechanics and Molecular Dynamic Calculation, Synthesis and Antibacterial Activities of Pyrazolin-β-diketone Ligands
    WANG Jin-Ling, YANG Yun, ZHANG Shu-Ming, LI Jian-Tong, MIAO Fang-Ming, ZHAO Jun
    2002, 23(2):  226-229. 
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    Molecular mechanics calculation and molecular dynamic study of two pyrazolin-β-diketone ligands were carried out by using systematic search and simulated kinetics programs. 1-Phenyl-3-methyl-4-(4-chlorobenzoyl)-pyrazolin -5-one(compound-A) and 1-phenyl-3-methyl-4-(4-nitrobenzoyl)-pyrazolin-5-one(compound-B) were synthesized. Antibacterial activities were also determined by using paper disc method. Guassian 94program was used to perform quantum chemistry ab initio calculation, the result of which coincides essentially with the antibacterial activities.
    Effect of Exhausting Exercise on Amino Acid Neurotransmitters in Hypothalamus of Rats
    ZHANG Dong-Ming, ZHANG Jia-Min, MA Wan-Yun, CHEN Die-Yan, HAN Hui-Wan, SHU Hong-Jun, LIU Guo-Quan
    2002, 23(2):  230-233. 
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    A simple and effective coupling of microdialysis and capillary electrophoresis with laser induced fluorescence detection technique was applied to the analysis of amino acid neurotransmitters in hypothalamus of rat after an acute exhausting exercise. The separation of amino acids was achieved by using an uncoated fused silica capillary(57 cm×75 μm i.d.) with a buffer of 10 mmol/Ldisodium tetraborate at pH 10 and an applied voltage of 12.5 kV. The detection limit was 10-10 mol/Lfor each amino acid. It is sufficiently sensitive and rapid for the determination of amino acid in 5μL Microdialysate. In comparison to pre-exercise, a significant increase in the levels of 6 hypothalamic amino acids(arginine, glycine, lysine, glutamic acid, alanine, γ-amino-n-butyric-acid) after exercise was found. These results demonstrate that increase of metabolic amino acids in hypothalamus of rats can be induced by exhaustive exercise and suggesting that amino acid neurotransmitters may play functional roles in the central effects of exercise.
    Studies on Flavans(Ⅱ) ——Total Synthesis of 4'-Hydroxy-5,7,3'-trimethoxyflavan and 5,4'-Dihydroxy-7,3'-dimethoxy Flavan
    YANG Jin-Hui, LI Ying, XUE Ji-Jun, LI Wei-Dong, LI Yu-Lin
    2002, 23(2):  234-237. 
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    4'-Hydroxy 5,7,3'-trimethoxyflavan and 5,4'-dihydroxy-7,3'-dimethoxyflavan were first synthesized by selective methylation, methoxymethylation, condensation, cyclization, deoxygenation from 2,4,6-trihydroxyacetophone and vanillin.
    Decomposition of Complex of Estertin with Schiff Base and Characterization of Crystal Structure of Products
    LI Zhong-Fang, WANG Su-Wen, WANG Yu-Xin, FU Fang-Xin
    2002, 23(2):  238-242. 
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    Complex MeO2CCH2CH2SnCl4-·H+(4) and MeO2CCH2CH2SnCl2·(2-OC6H4-CH＝NC6H5)(5) were obtained by decomposing the yellow reaction solution of MeO2CCH2CH2SnCl3· (2-HOC6H4CH＝NC6H5) (3), which is the product of β-methoxycarbonylethyltin trichlorides(1) with Schiff base (2-HOC6H4CH＝NC6H5)(2), after standing for 15 d. Complexes 4 & 5 were characterized by elemental analysis, IR　and NMR. The crystal structure of complex 4 was determined by X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group P2cn, a =0.7852(2) nm, b = 1.2236(10) nm , c =1.6952(4) nm, α= β =γ =90°, V = 1.6287 nm3, Z =4, Dc =1.79 g/cm3, F (000) = 860, μ =22.2 cm-1 , R=0.0449, wR =0.0382 . Complex 4 exists as a discrete molecule, and the tin atom attains a distorted octahedral geometry via the coordination of intramolecular carbonyl oxygen and chloride ion. The coordination number of tin atom is 6. In complex 5, one chloride ion is replaced by the phenolic oxygen anion. Coordination of carbonyl oxygen atom to tin atom still exists, The coordination number of tin atom is 5.
    Organic Chemistry in Neurodegenerative Disorders ——Physical Organic Chemistry and Bioorganic Free Radical Chemistry of Prion Protein
    YANG Chi-Ming
    2002, 23(2):  243-250. 
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    The central event in prion diseases(including mad cow disease) is the structural transformation of a single protein, i.e ., prion protein, from its benign form to its diseased and infectious form. Protein only hypothesis as an evolutionary model for viral replication has been tested in a rigorous way in prion research. In the diseases, the spontaneous and irreversible protein structural transformation was completed within a few months, the uniformly generated infectious prions displays an extraordinary resistance to inactivation, and exhibits a high ability to infect animals, suggesting that a vital energy source is required for the production of infectious prions. Considering the high oxygen-respiration rate in the brains of mammals, oxidative damage to prion protein can be the crucial factor. Both theoretical consideration of the nature of protein radical reactions and a large body of previously unraveled feature of scrapie and prion diseases have provided multiple distinct lines of compelling evidence, persuasively supporting a conclusion that the infectious agents are prion(free) radicals produced from protein oxidative damage. To facilitate a better understanding of the prion chemistry, in this multidisciplinary review, clinical, physiological, immunological and biochemical aspects of the diseases are provided to demonstrate for the frist time that diseased(infectious, scrapie) prions are very likely formed from prion radical-mediated oxidative damage to prion proteins.
    Thermokinetic Study on the Growth Process of Halobacterium Halobium
    HUANG Yu-Ping, LIU Yi, SHEN Ping, QU Song-Sheng
    2002, 23(2):  251-254. 
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    By using LKB2277 Bioactivity Monitor, we determined the thermogenic power curves of Halobacterium halobium R1, J7, S9 and F9. Thermokinetic equation, ln[ P(1-P/Pm)r-1 ]=ln[ P0(1-P0/Pm)r-1 ]+kt ,was established based on the characteristics of growth curves. The growth rate constants(k) of Halobacterium halobium growth were obtained. This thermokinetic equation is very suitable for Halobacterium halobium growth. It was compared with exponential and logistic growth model. It is very significant for the study of the growth and characteristics of the third kind of life, Archaea.
    Synthesis, Assembly and Characterization of Nanoparticle Composite CdS/TAB
    HONG Xia, WEI Li, AI Xin, WANG Gang, LIU Feng-Qi, SHAO Hui-Bo, BAI Yu-Bai, LI Tie-Jin, TANG Xin-Yi
    2002, 23(2):  255-258. 
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    The nanoparticle composite CdS/TAB(dimethyldioctadecyl ammonium) is synthesized. It is investigated by IRspectroscopy, UV spectroscopy, X-ray diffraction, TEM, AFM and SPS, which prove the existence of CdSnanocrystal and the formation of core shell structure. Also, the size of the composite can be controlled by altering the ratio.In the meantime, it is indicated by EFM that such orderly assembly substance can form electrostatic field superlattice.
    Preparation and Characterization of Nanoscales α-Fe2O3/Microporous resin Catalyst and the Application in Hydroxylation of Phenol with H2O2 to Dihydroxybenzene
    LIU Qing-Sheng, YU Jiang-Feng, YE Qiu-Shi, FU Ying-Huan, XU Ning, WU Tong-Hao
    2002, 23(2):  259-262. 
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    The nanoscales α-Fe2O3 /microporous resin catalyst was prepared by the ion exchange method and characterized by means of X-ray diffraction(XRD), transmission electron microscopy(TEM) and Mssbauer spectroscopy. The uses of these techniques make it possible to perform an estimation of the size of the iron oxide crystallites on microporous resin. The size of the crystallites has been found to be smaller than5 nm. The catalyst prepared exhibited a very good catalytic activity on the hydroxylation of phenol with H2O2 to dihydroxybenzene. The effect conversion of phenol reached 22.4% when phenol/H2O2(molar ratio) is 3 and the ratio of catechol and hydroquinone is about 1.4 in the products. The results didn't change when the reaction was magnified to 3000 times. Furthermore, compared α-Fe2O3 /microporous resin with α-Fe2O3 prepared from chemical precipitation, it was thought that the reason of different hydroxylation activity of phenol between the two kinds of catalysts was the size of particles in nature.
    Quantum Chemical Investigation of Geometry and Stability of Silicon-Phosphorous Clusters SinPm+(n+m=5)
    WANG Su-Fan, FENG Ji-Kang, SUN Chia-Chung, GAO Zhen, KONG Fan-Ao
    2002, 23(2):  263-266. 
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    On the basis of the relative experiment, the possible geometrical structures and relative stability of silicon-phosphorous clusters SinPm+(n+m =5) are explored by means of density functional theory (DFT) quantum chemical calculations(B3LYP/631G*). The effects of polarization functions and electron correlation are included in these calculations. As a result, the stability regularity of the SinPm+ cluster is obtained, that is, when n>m , the most stable structure of the clusters is similar to Sin+, otherwise, it is similar to Pm+.
    Ab initio Study on the Intermolecular Interaction of CH3F
    HU Zong-Chao, WANG Yi-Bo
    2002, 23(2):  267-270. 
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    Various possible structures of the CH3F dimer have been optimized at the MP2/6-311+ +G(3d,3p) electron correction level, three minimum geometrical structures have been found on the potential energy surface. At a high order electron correction MP4SDTQ and CCSD(T)/6-311+ +G(3df,3pd) level, the binding energy of the most stable structure which is planar cyclic C2h symmetry of the dimer has been calculated exactly and the binding energy ΔECPCCSD(T) is -9.707 kJ/mol. The calculated results of the harmonic vibrational frequencies of three minimum geometries support the structures guessed by the spectra experiment. Diversity of the harmonic vibrational frequency has been explained.
    Theoretical Studies on the Crystal Packing Form of MT-Ⅱ from Rat Liver
    HOU Ting-Jun, AN Yu, RU Bing-Gen, XU Xiao-Jie
    2002, 23(2):  271-274. 
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    Considering that the conformational units should be the same in solution as in crystals during crystallization equilibrium, the minimal crystal packing unit is determined by the style of protein aggregations in solution. Based on the comparison of MT-Ⅱ from rat liver and MT-Ⅰ and MT-Ⅱ from rabbit, it could be proven that in NaH2PO4-Na2HPO4 buffer, the aggregate of MT-Ⅱ from rat liver would be tetramer, not dimer. From the analysis of the crystal packing model, it could be naturally deduced that the crystals were obtained from the packing of tetramers; moreover, the crystal packing could be comprehended more deeply by using the tetramer packing model.
    Studies on the Relationship Between Substrate Temperature and Structure of CNx Thin Films Deposited by R.F. Magnetron Sputtering
    CAO Pei-Jiang, JIANG Zhi-Gang, LI Jun-Jie, JIN Zeng-Sun, WANG Xin, ZHENG Wei-Tao, LI Zhe-Kui
    2002, 23(2):  275-278. 
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    CNx thin films were synthesized on Si(001) at different substrate temperatures(ts=room temperature, 350, 500 ℃) by R.F. magnetron sputtering method, Raman spectroscopy, FTIR spectroscopy and XPSwere used to study the relationship between the chemical binding state of CNx thin films and temperature. Raman spectra shows that with the increase of ts, Db and position shifted towards a lower frequency, while Gband position shifted towards a higher frequency. Their full width at half-maximum decreased from 375 and 150 cm-1 to 328 and 142 cm-1 respectively, and the ratio of ID/IG decreased from 376 to 288 too. Except for disorder Dband(1400 cm-1) and graphitic Gband(1570 cm-1), ca . 700, ca . 2210(C≡N), 2330(C-O) and 3255-3351 cm-1 (N-H) appeared in FTIRspectra. From XPS spectra we can conclude that with the rise of t s, mol ratio of N/Cdecreased from 049 to 038, while the compound ratio of sp2(C-N) to sp3(C-N) had a trend of increasing. Lower annealing temperature(350 ℃) had no significant effects on the chemical binding state of CNx thin film, but higher annealing temperature(900 ℃) led to the better crystallization degree of the sample.
    Performance of a Novel Phosphonium Ligand PDBPDS in Hydroformylation Reaction
    ZHANG Jing-Chang, YAN Bin, CAO Wei-Liang, LI Jiang-Bo
    2002, 23(2):  279-282. 
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    Structures of 1-phenyldibenzophosphole disulfonate(denoted as PDBPDS) and triphenylphosphorus trisulfonate(denoted as TPPTS) were optimized by using quantum chemical AM1 method. Both stereo and electronic structure show that PDBPDSacts as a better ligand than TPPTSin the Rh/Pcatalyst system of hydroformylation. The performance of the novel ligand PDBPDS in water soluble Rh complex, HRh(CO)(PDBPDS)3, was conducted in biphasic hydroformylation of propylene. The influences of reaction parameters such as reaction temperature, n (PDBPDS)/ n (Rh) and agitating speed on catalytic properties were investigated. The result shows that under the condition of 2.0 MPa, 100 ℃, n (PDBPDS) / n (Rh)=35, agitating speed 500 r/min and V (H2)/ V (Co)=1/1, TONis 2800 g(butyraldehyde)/ and the n (normal)/ n (iso) reaches 12.3, concentration of Rh in the organic phase is only 3.6×10-8 mol/L. Compared with the performance of TPPTSunder the same condition, both activity and selectivity are remarkably improved. Further, the catalyst can be easily separated from the reaction system.
    Studies on Photocatalytic Activity of Perovskite Type LaFe1-x CuxO3
    FU Xi-Xian, YANG Qiu-Hua, SANG Li-Xia
    2002, 23(2):  283-286. 
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    LaFeO3 and a series of Cu-doped compounds LaFe1-x CuxO3 were prepared by citrate method. The photodegradation experiments of various water soluble dyes were carried out in the suspension of LaFe1-x CuxO3 acting as the photocatalysts. The photocatalytic activity of LaFeO3 and LaFe1-x CuxO3 was studied with IR, UV-Vis, and photoacoustic spectroscopy. The influence of doping on photocatalytic activity was also analyzed by PATand XPStechnology. The results show that the doping can greatly improve the photocatalytic activity of LaFeO3.
    A Study of the Properties of Aqueous Systems of Mixed Derivatives of 10-Undecenoic Acid
    HE Xu, LI Hong-Bo, HUANG Jian-Bin, TANG Shi-Hua, ZHU Bu-Yao, ZHENG Rong
    2002, 23(2):  287-290. 
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    The surface activity and aggregate behavior of the mixed systems of N,N-[2-(10-undecenoylmethyltaurine)]sodium(UDMTS) and trimethyl [2-(10-undecenoyloxylethyl)] ammonium iodide were investigated. According to the regular solution theory, the molecular interaction parameters and the composition of the surface adsorption layer and micelle have been calculated. It was revealed that double bond at the end of hydrophobic chain, ester-bond and amido-bond near the hydrophilic group of the surfactant molecule reduce the molecular interaction between cationic and anionic surfactant molecules. Furthermore, tiny amount of fatty alcohol is effective to a transition from micelle to vesicle.
    Properties of Electric Double-layer Capacitors Using Activated Carbon Prepared from Pyrolytic Treatment of Sugar as Their Electrodes
    HUANG Xiao-Wen, XIE Zhong-Wei, QU Xiao-Guang, WANG Qing-Wei, QU Lun-Yu, XIE De-Min
    2002, 23(2):  291-293. 
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    A new precusor of activated carbon material——sugar was pyrolyzed under many different conditions. Experiments were carried out to search for optimal pyrolyzing conditions. It was found that sugar should be carbonized at 700 ℃ and activated with potassium hydroxide at 800 ℃. The activated carbon prepared from pyrolytic treatment of sugar is therefore potential candidates as electrode material of electric double layer capacitor.
    Studies on Contributions of Chemical Components to Lead Adsorption by Different Natural Surface Coatings
    DONG De-Ming, HUA Xiu-Yi, LI Yu, KANG Chun-Li
    2002, 23(2):  294-296. 
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    Surface coatings developed in three lakes and a river in Jilin Province, P. R. China were used to study the role of the composition of natural surface coatings in controlling Pb adsorption. Extraction techniques were used to remove one or more chemical components from surface coatings. Pb adsorption to the extracted and unextracted surface coatings was measured. The observed Pb adsorption to the extracted and unextracted surface coatings were analyzed using nonlinear least squares fitting(NLSF) to estimate the relative contribution of chemical components to the total Pb adsorption of surface coatings. In different waters, the contribution to Pb adsorption for each chemical component was different, but in all the waters studied here, metal oxides(Fe oxides and Mn oxides) contributed the most, with a relative small contribution of organic phase.
    Preparation, Structure and Photochromic Properties of Dilong-chain Alkyl Group Dawson Type Molybdophosphoric Acid Multicomposite Films
    ZHANG Tie-Rui, FENG Wei, LU Ran, BAO Chun-Yan, ZHAO Ying-Ying, LI Tie-Jin, YAO Jian-Nian
    2002, 23(2):  297-299. 
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    A multicomposite P2Mo18 /DODA self-assembled multilayer film was fabricated by casting the chloroform solutions of ionic complex between a dimethyldidecylammomium and a phosphomolybdate anion onto the borosilicate glass and calcium fluoride substrates. Infrared spectra revealed that the Dawson strcucture characteristic of the P2Mo18 O626- anion was presented in the composite film. Awell ordered superlattice structure, d-spacing 3.59 nm, was identified by X-ray diffraction. The composite film shows good photochromic properties. Under the irradiation with UVlight, the transparent film changed from yellow to blue. Then, bleaching occurred when the film was in contact with ambient air or O2 in the dark. If the UVirradiated films were stored in nitrogen, helium, argon or vacuum conditions, it could retain blue coloration for a long time. It suggests that oxygen plays an important role during the bleaching process. The photochromic mechanism of the composite film was studied by UV-Vis spectra, FTIRspectra and ESR. The appearance of IVCTbands shows that electron transfer occurs between the organic substrate and heteropolyanion, converting heteropolyanions to heteropolyblues with simultaneous oxidation of the organic substrate. Observation of UVinduced ESRsignal suggests that electron transfer takes place in the lattice and P2Mo18 O626- acting as an acceptor gets electrons during UVirradiation. The changes of IRspectra for the composite film after UVirradiation are another powerful proof to identify the DODA was oxidized and P2Mo18 O626- was reduced in the photochronic process.
    High-temperature and High-pressure Extraction of Lnn@C2n(Ln=Y,Gd,Tb)
    SUN Shu-Qing, LIU Zhi-Qiang, XING Jun-Peng, LIU Shu-Ying 
    2002, 23(2):  300-302. 
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    A high temperature and high pressure method was used to efficiently and selectively extract metallofullerenes Lnm@C2n (Ln=Y, Gd, Tb) in a closed stainless steel autoclave under inert gas protection. 1,2,3-Trichlorobenzene was found to be more effective and selective for the extraction of Ln@C82 (Ln=Y, Gd, Tb) from empty fullerenes and other metallofullerene species.
    Thermodynamic Feasibility and Sulfur Formation Mechanism of Desulfurization with Sodium Phosphomolybdate
    WANG Rui
    2002, 23(2):  303-305. 
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    A new method of natural gas desulfurization has been developed by employing the heteropoly compound of the rich elements of our country. This method enables hydrogen sulfide to be removed and element sulfur to be recovered simaltaneously. The thermodynamic feasibility of simultaneous desulfurization and sulfur recovery from natural gas with the solution of heteropoly compound was proved to be applicable by the experimental result of potential pH-curves. At present, no proof was given on the exact number of electron transferred during the redox reaction between sodium phosphomolybdate and reductants including hydrogen sulfide. The research here also reveals the reaction mechanism between sodium phosphomolybdate and hydrogen sulfide. With the aid of ISE, DSC and EMS, the mechanism of desulfurization reaction was studied. The reaction products contain little deposition compounds of molybdenum and vanadium, indicating that sodium phosphomolybdate is still much stable in its chemical property after many times of absorption regeneration cycles, the agent loss is much lower than that of the chelate iron method. The chemical equation of sodium phosphomolybdate and H2S was proposed to be: H2S+Na2HPMo12Ⅵ O40→S↓+Na2H3PMo10ⅥMo20Ⅴ40 i.e ., there are two Mo(Ⅵ) atoms reduced to Mo(Ⅴ). Therefore, the theoretical saturation sulfur loading capacity of sodium phosphomolybdate is twice that of chelate iron with the same molar concentration.
    Preparation of Polymer/Silica Nanoscale Hybrids Through Sol-Gel Method Involving Emulsion Polymers(PMMA/SiO2)
    TONG Xin, TANG Tao, ZHU Ning, FENG Zhi-Liu, HUANG Bao-Tong
    2002, 23(2):  306-309. 
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    The different poly(methyl methacrylate)(PMMA)/SiO2 hybrids were prepared through sol-gel method involving PMMA emulsion(emulsion method) and PMMA/THF solution(solution method). The samples were characterized by differential scanning calorimetry(DSC), thermogravimetry analysis(TGA), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results showed that PMMA/SiO2 composites in nanoscale were prepared by emulsion method, and its size of phase heterogeneity was less than that of solution method. Meanwhile, the polymer emulsion as the reactive medium was more suitable for the formation of SiO2 network.
    The in situ Reaction of PSBR and the Correlation Study of Hybrid Elastomer
    ZHANG Ming, LI You-Rong, YAN Chang-Hao, Nakakita Satoshi, Inoue Shinich, Okamoto Hiroshi
    2002, 23(2):  310-313. 
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    Pyridinium salt was produced by using reaction of vinylpyridine-SBR(PSBR) latex with propyl bromide, and then it reacted with aluminum alkoxide, alkyl titanate and active silanol to prepare a organic/inorganic hybrid elastomer latex(PSBR-MnOm). Akind of composite vulcanizate was obtained after the hybrid elastomer was compounded with natural rubber. Its mechanical performance is rather good and its hysteresis loss is quite high. In addition, it is similar in compression set to NR. Its structure was analyzed by FTIR, high-resolution NMR, DSC and TGetc .. It is believed that the existence of "huge metastable complexes" in the metal-containing composite vulcanizate may improve its mechanical properties.
    Studies on the Miscibility of Poly[bis(glycine ethyl ester) [JZ]phosphazene]/Polyesters Blends
    QIU Li-Yan
    2002, 23(2):  314-317. 
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    Poly[bis(glycine ethyl ester)phosphazene] was blended with poly(d,l-lactide)(PLA) or poly(d,l-lactide-co-glycolide)(PLGA) in various mass fraction ratios by using solvent-mixing technique. The miscibility of these blends was studied by DSC, IRand contrast microscopy method. The results showed that PGPwas completely incompatible with PLA, but partially compatible with PLGAdue to the hydrogen bonding effect. Furthermore, the miscibility of PGP/PLGAwas improved with the increase of PLGAcontent in the blend.
    Some New Rate-accelerating Additives for Nitroxide-mediated Living Free Radical Polymerization of Styrene
    LIN Jian, LI Wan-Li, YAN Ming-Fa, ZHUANG Rong-Chuan, ZOU You-Si 
    2002, 23(2):  318-320. 
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    Living free radical polymerizations of styrene were studied with the initiator of benzoyl peroxide in the presence of TEMPO(2,2,6,6-tetramethylpiperidinyl-1-oxy). The purpose of this paper is to explore the polymerization rate enhancement by means of using additives. It was found that styrene polymerization was distinctly accelerated by the addition of small amounts of a 1,3-diketone(acetylacetone, AAT) , a β-keto ester(acetoacetic ester, AAE) or diethyl malonate(DEM) and a strong organic anhydride(trifluoroacetic acid anhydride, TFA). However, some of strong organic acid, chloroacetic acid(CAA), bromoacetic acid(BAA) and 2,4,6-trinitrophenol(TNP) did not enhance the rate of the stable free radical mediated polymerization.
    Synthesis and Characterization of Novel Fluorine-containing Poly(aryl ether ketone)s
    LIU Bai-Jun, CHEN Chun-Hai, HU Wei, SUN Hui, ZHAO Shuang, JIANG Zhen-Hua, ZHANG Wan-Jin, WU Zhong-Wen
    2002, 23(2):  321-323. 
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    A kind of highly fluorinated bisphenol monomer was synthesized. It was characterized by FTIR, 1H NMR and MS. 6F-PEEK and 6F-PEEKK were prepared via aromatic nucleophilic substitution, based on [3,5-di(trifluoromethyl)] phenylhydroquinone and difluoro monomers. The Tgs of 6F-PEEK and 6F-PEEKKare 423 and 436 K, respectively. The 6F-polymers exhibit a high thermal stability and good solubility. The flexible, creasable and transparent thin films were easily obtained by compression moulding and solution casting.
    Synthesis and Characterization of Novel Soluble Poly(aryl ether ketone)s
    LIU Bai-Jun, CHEN Chun-Hai, JIN Yu-Hui, HU Wei, SUN Hui, WU Zhong-Wen, JIANG Zhen-Hua, ZHANG Wan-Jin
    2002, 23(2):  324-326. 
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    Two novel poly(aryl ether ketone)s based on (3-methyl)phenylhydroquinone were synthesized via aromatic nucleophilic substitution reaction. The high molecular polymers were easily obtained because of the high reaction activity of bisphenol monomer. The traces of DSC showed that the Tgs of m-TPEEK and m-TPEEKK were 421 and 432 K, respectively. The two polymers exhibit a high thermal stability and good solubility. The transparent and flexible films were readily prepared with chloroform solution. The film of m-TPEEK had a low dielectric constant(ε =27).
    Preparation of Epoxy Resin Waterborne Dispersions by Surfactant Free Phase Inversion Emulsification
    QIU Dong, YANG Zhen-Zhong 
    2002, 23(2):  327-329. 
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    Based on the insight into the mechanism of phase inversion emulsification in the presence of curing agents, a new method called surfactant free phase inversion emulsification was proposed to prepare epoxy resin waterborne dispersions. The waterborne particles are in sub-micron range with narrow size distribution. Transparent cured films could be formed from the dispersions even at ambient temperature. The stability of the dispersions could be enhanced by post-polymerization at a high temperature for some time. The knowledge about the phase inversion and the stability of the waterborne dispersions might provide a new way to enhance oil recovery.
    Template-synthesis of Ordered Macroporous Syndiotactic Polystyrene Using Silica Colloidal Crystals
    YAN Wei-Dong, LI Dan, RONG Jian-Hua, YANG Zhen-Zhong
    2002, 23(2):  330-332. 
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    A rigid silica colloidal crystal template was formed by self-assembly of the monodispersed silica dispersion prepared according to Stöber method. Within the interstitial void of the template, β-diketonate titanium complexes[(dbm)3Ti(OPh)/MAO] catalyzed polymerization of styrene was carried out to form syndiotactic polystyrene(sPS)/silica composites. The titled ordered macroporous syndiotactic polystyrene was achieved by chemical decomposition of the silica template with concentrated aqueous hydrofluoric acid, which was confirmed by SEM results. FTIR spectra indicated that all silica was removed from the composites in this study. DSCrevealed that the as prepared macroporous sPSwas significantly different from the bulk one, and the unique properties were inherent rather than from the enforcement effect by the silica template. Further investigation concerning the inherent microstrucutures about the molecular weight and its distribution, tacticity of the styrene etc . and their dependence on the confinement is in progress.
    Synthesis and ESR Study of a Novel Phosphorylated Lipophilic Spin-trap
    XU Ying-Kai, CHEN Zhong-Wei, SUN Jian, LIU Ke, CHEN Wei, SHI Wei, WANG Hong-Mei, ZHANG Xing-Kang, LIU Yang
    2002, 23(2):  333-335. 
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    Synthesis of a novel α-phosphorus containing spin-trap, DEPPEPO[5-(diethoxyphosphoryl)-5-phenylethyl-1-pyrroline] N-oxide and evaluation of its ability to spin trap the hydroxyl and the superoxide anion radicals were described in the present article. The ability for trapping an active superoxide anion radicals generated in the HX/XO system and the stability of their spin adduct of DEPPEPO were analyzed. In addition, the effects of 5-phenylethyl and 5-phenyl substituted analogues of DMPO on the stereochemistry of the corresponding spin adducts were systematically illustrated.
    Synthesis of Heat-resistant Star-shaped Copolymer of Methyl Methacrylate
    XIA Ping, JIANG Xu-Lin, YAN De-Yue
    2002, 23(2):  336-338. 
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    Four-armed star-shaped copolymer of methyl methacrylate(MMA)/ N-cyclohexylmaleimide(NCMI) with heat-resistance was synthesized by atom transfer radical copolymerization with the CuBr/bpy catalyst in anisole, initiated by tetra(bromomethyl)benzene. Alinear plot of ln([M]0/[M]) versus reaction time was obtained by using anisole as solvent. In contrast, the use of cyclohexanone as solvent results in that the rate of copolymerization decreases as the reaction proceeds. Using anisole as the solvent in the copolymerization, the molecular weight of the resultant copolymer(measured by triple detection SEC) increased linearly with the increase of conversion, and the molecular weight distributions are narrow. The glass transition temperature of the resultant copolymer was higher than that of the pure PMMA. The synthesized four-armed star copolymer was used as macroinitiator for the cationic polymerization of 2-methyl-2-oxazoline to yield star shaped poly(MMA-co- NCMI)/poly(2-methyl-2-oxazoline) block copolymers. The approximately linear increase of the molecular weight with the increase of reaction time and the low molecular weight distribution demonstrate a controlled chain extension reaction.
    Surfactant-template Synthesis of Mesoporous Silica Monolith via Fast Sol-gel Process
    QI Kai, YANG Zhen-Zhong, YANG Yun-Xin, ZHAO De-Lu
    2002, 23(2):  339-341. 
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    Surfactant-template synthesis of mesoporous silica monolith was carried out via modified fast sol gel process. It was easy to obtain crack-free silica monolith due to low volume shrinkage during the gelation. The morphology of the titled silica was characterized by transmission electron microscopy and X-ray diffraction. The results showed that the pores were worm like and the pore size was about 4 nm. Further nitrogen isothermal absorption experiment indicated that the specific area of the titled material was 391 m2/g, which was comparable with the reported value 306 m2/g in literature.
    Self-assembly of Diazoresin and P[ N-(4-hydroxyphenyl)acrylamide via H-bonding Interaction
    YANG Zhao-Hui, CAO Ting-Bing, CHEN Jin-Yu, CAO Wei-Xiao 
    2002, 23(2):  342-344. 
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    The self-assembly between diazoresin(DR) and the homopolymer or copolymers of 4-N-hydroxyphenyl acrylamide(NHPA) has been investigated.It was confirmed that the driven force of the assembly is H-bonding attraction, in which the DR plays a role of H-acceptor, while the NHPA polymers act as a H-donor, Under UV, the multiayer films become very stable towards polar solvents. For example, no any change was observed when the irradiated film was immersed in DMF at 20 ℃ for 12 h, but the unirradiated film was destroyled completely when it was immersed in DMFat the same temperature for 20 min. The dramatically improvement for the stability of the film towards polar solvents should be attributed to the bond conversion of the layers from H-bond to covalent bond under UV irradiation.
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