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    10 April 2006, Volume 27 Issue 4
    高等学校化学学报2006年第27卷第4期目次
    2006, 27(4):  0.  doi:
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    Contents
    Studies on Inhibition of Algal Polysaccharide Isolated from Marine Algae Eucheuma Striatum to Growth of
    Urinary Crystal Calcium Oxalate
    DENG Sui-Ping, WU Xiu-Mei, OUYANG Jian-Ming*
    2006, 27(4):  595-598. 
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    The influence of sulfated polysaccharide(ESPS) isolated from marine algae Eucheuma striatum on the crystallization of calcium oxalate was investigated by means of scanning electron microscopy, infrared spectrum and X-ray diffraction. The results indicate that the addition of ESPS could inhibit the growth of calcium oxalate monohydrate(COM) and induce the formation of calcium oxalate dihydrate(COD) crystals. With the increase of ESPS mass concentration from 0 to 0.03 and 0.50 mg/mL, the percentage of COD crystals increased from 0 to 10% and 55%, respectively; the stabilization of the(101) face of COM crystals was strengthened, the(020) face was weakened; the morphology of COM crystals changes from threedimensional crystals to tetragonal slice crystals; and the size of both COM and COD crystals apparently become smaller. It is indicated that ESPS may be a potential inhibitor to calcium oxalate urinary stones.

    Preparation and Characterization of Y2O3/ZrO2 (YSZ) Hollow Fibre Membranes
    MENG Xiu-Xia, YANG Nai-Tao, MENG Bo, TAN Xiao-Yao
    2006, 27(4):  599-601. 
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    Fluorite-type Y2O3/ZrO2(YSZ) powders with the mean particle size of 1.74 μm were synthesized by the citric acid combustion method. Using the prepared YSZ powders, gastight hollow fibre membranes were fabricated by a dry-wet spinning process based on the phase inversion technique, followed by sintering at 1 400 ℃ for 4 h. The gas tightness, porosity, mechanical strength, microstructure and crystalline phase of the hollow fibre membranes were studied. The results indicate that the prepared YSZ hollow fibre membranes are gastight while the porosity remains around 23.04% and the bending strength may be up to 322 MPa. The diameter of the pores in the hollow fibres ranges from 60 to 500 nm. XRD spectra show that the fluoritetype phase is kept unchanged, but the crystal size grows bigger after sintering. SEM micrographs show that the prepared YSZ hollow fibre membranes possess an asymmetric structure that includes a dense layer and porous layers, while the inner and outer surfaces are also dense.

    Synthesis of Mesoporous Silica with Spiral Morphology by Using Chiral Anionic Surfactant
    QU Feng-Yu, ZHU Guang-Shan,LIN Hui-Ming, ZHANG Wei-Wei, LI Shou-Gui, QIU Shi-Lun
    2006, 27(4):  602-604. 
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    Anionic chiral template Ibuprofen and co-template 3-Aminopropyltriethoxysilane were employed to synthesize mesoporous silica with spiral morphology, and the sample was characterized by using XRD, FTIR, SEM and TEM methods, conforming its hexagonal mesoporous structure and spiral morphology.

    Preparation and Reduction Process of the Ni-Fe Alloy Nanoparticles by Aluminum Powders in a Mixed Sulfate Solution
    ZHANG Ting-Ting, ZHOU Zeng-Jun, ZHANG Qi-Yun*, LI Xing-Guo
    2006, 27(4):  605-607. 
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    The 11.3 nm diameter nanopowders of Ni dominated Ni(Fe) solid solution can be prepared by using aluminum powder to react with FeSO4. (NH 4)2 SO4 and NiSO4. (NH4)SO4 mixed solution. In the product, the Fe atoms replaced parts of the Ni atoms.  While the mass fraction of Ni 2+ /(Fe 2+ +Ni 2+ ) in the solution  is higher than 76%, solid solution of homogenous phase Ni(Fe) can be obtained. If the content ofNi 2+ /(Fe 2+ +Ni 2+ ) lower than this point, the Ni(Fe)+Fe or Fe+Ni 0.36 Fe 0.64 mixed phase nanopowders will be produced.

    Articles
    Solid-phase Extraction of Active Component of  Chinese Traditional Medicine  Fisetin by Using Molecularly Imprinted Polymers
    LI Li, HU Shu-Guo, HE Xi-Wen, LI Wen-You, CHEN Lang-Xing, ZHANG Yu-Kui
    2006, 27(4):  608-611. 
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    Fisetin is the main function integrant in Cotinus coggygria scop of Chinese traditional medicine. Using fisetin as imprinted molecule, acrylamide as the functional monomer, and EDMA as the  crosslinking agent, a polymer was prepared by molecular imprinting technique. The polymer was loaded into the self-made solid-phase extraction(SPE) cartridge. A SPE procedure was suggested for extracting and concentrating fisetin by  using different volume fractions of ethanol in aqueous solution as the loading conditions. In order to optimize the washing and eluting solution, the adsorption of fisetin in different solutions was studied. It was found that the fisetin and analogue quercetin were separated primely.

    Separation and Analysis of Constituents of Acidic Compounds in Tobacco Leaf by Using Comprehensive Two-dimensional Gas Chromatography/Time-of-Flight Mass Spectrometry
    LI Hai-Feng, LU Xin, LU Hong-Liang, MA Chen-Fei, ZHU Shu-Kui, KONG Hong
    2006, 27(4):  612-617. 
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    Comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry(GC×GC-TOFMS) was applied to the  characterization of volatile and semi-volatile acidic compounds in oriental tobacco leaf. Simultaneous distillation extraction(SDE) was used as the sample extraction method. Two types of column sets were compared, and appropriate GC×GC separation conditions were suggested. The separation behavior on two-dimensimal plot of different kinds of compounds were investigated. TOFMS library search combining with  structured chromatogram of GC×GC was used to identify the acidic compounds in tobacco leaf. A total of 143 acidic compounds were tentatively identified, including 10 acid anhydrides, 43 organic acids and 90 phenolic compounds. The results show that GC×GC-TOFMS method is suitable for separation and identification of complex sample.

    Sample Pretreatment Microfluidic Chip for DNA Extraction from Rat Peripheral Blood
    CHEN Xing, CUI Da-Fu, LIU Chang-Chun, LI Hui, ZHAO Wei-Xing
    2006, 27(4):  618-621. 
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    A sample pretreatment microfluidic chip was described based on the principle of solid phase extraction(SPE) and the MEMS technology. Oxidized porous silicon with a large surface area as the solid phase matrix for absorption DNA from biologic sample can greatly improve the DNA yield. The factors which can affect the DNA yield were analyzed and the preparation technology and the experiment procedure were improved. The DNA purification process from the rat peripheral blood can be achieved and the DNA yield is 24  ng/(μL whole blood), which can reach the level of the commercial DNA purification kits. Furthermore, the DNA extracted from the whole blood can be amplified by PCR, which can achieve a high efficiency of the amplification.

    Separation of Solutes Containing π-Electron on  Pyrenebutyric  Acid-bonded Silica Stationary Phase by HPLC
    YU Qiong-Wei, QU Li, HE Hai-Bo, FENG Yu-Qi*
    2006, 27(4):  622-626. 
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    The chromatographic performance of pyrenebutyric acid-bonded silica phase was evaluated by studying the separation of solutes containing π-electron. The results show that the PYB not only have the hydrophobicity and charge-transfer ability but also have the planar recognized ability, and could separate well such solutes containing  π-electron  as polycyclic aromatic hydrocarbon and some nitroaromatic hydrocarbons. The stationary phase has a high stability at a pH value between 3.5 and 7.0. The silanophilic activity of the PYB was weakened because of the existence of the amide group in the packing. It can be efficiently used for the analysis of basic compounds.

    Investigation on the Distribution Characteristics of Trace Heavy Metals in the Natural Surface Coatings Samples(NSCSs)
    LI Yu, CHEN Jie-Jiang, WANG Xiao-Li, DONG De-Ming, GUO Shu-Hai
    2006, 27(4):  627-631. 
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    The chemical fractions of manganese, iron, copper, lead, zinc and cadmium in the natural surface coating samples(NSCSs), which were collected in the Songhuajiang River, were investigated by using the modified sequential extraction procedure in order to identify the relative roles of Fe/Mn oxides and organic materials in the NSCSs in controlling heavy metals adsorption.  The results show that trace metals were mostly present as solid oxides/hydroxides with 62.9%, 58.3%, 53.8% and 326% for Cu, Zn, Pb and Cd, and little were bound to organic material with 1.1%, 0.6%, 9.9% and 1.8% for Cu, Zn, Pb and Cd, respectively.  It indicates that Fe/Mn oxides contributed the most to trace metals adsorption with less roles of  organic materials in trace metals adsorption.  These percent distributions of the trace metals in the NSCSs were also in excellent agreement with those obtained through direct experiments and reported in independent investigations from the natural surface coatings(NSCs) developed in natural waters.  Meanwhile, the results obtained in this paper could be confirmed through the selective extraction technique on the NSCS regardless of Fe oxides bound to residual. 

    Contents
    Intracellular Delivery of Fluorescent Dyes Mediated by Nanometer-Liposomes
    SUN Yue, LU Min, YIN Xua-Feng
    2006, 27(4):  632-634. 
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    A new method  that nanometer-liposomes could penetrate the cell membrane to deliver their encapsulated material into cells was investigated.  Nanometer sized-liposomes were produced from phosphatidylcholine to encapsulate fluorescent dyes and FITC labeled superoxide dismutase(SOD-FITC) by an ultrasonic method.  The size distribution of liposomes was determined with a Laser Particle Analyser.  The fluorescence images demonstrate that liposomes can transfer fluorescent dyes(FITC, Rhodamine B), which are not cell membrane permeable, into cells.  Single cell analysis of the delivered SOD-FITC with microchip electrophoresis revealed that the density of liposomes and interaction-time between liposomes and cells affected the efficiency of intracellular delivery of encapsulated material.
    Comparative  Analysis of Proteomes for Chemoresistance in Human Ovarian Adenocarcinoma Cell Line,  COC1/DDP
    LU Lei, LIU Zhi-Qiang, LI Li, LIU Ning, LIU Shu-Ying
    2006, 27(4):  635-637. 
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    The proteomic maps of  human ovarian adenocarcinoma cell line  in Human COC1 and its cell subline COC1/DDP were produced by 2-DE SDS-PAGE. The image analysis revealed obviously differential protein expression of the cells in response to cisplatin treatment. Approximate 1300 protein spots were resolved in the two ranges of pI(3—10). The spots which have 10-fold difference in light density were digested by in-gel enzyme, identified by matrix assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS) and finally detected by Profound and Mascot search engine in IDI databases. Seven proteins with obviously altered abundances were detected specifically, including four up-regulated protein spots and three down-regulated protein spots. The proteins differentially expressed in the parent cell line COC1 and its subline COC1/DDP were considered to be important for the  therapy and pathogenesis.

    A Microfluoidic Chip-based Capillary Electrophoresis System with Integrated     Supported-liquid-membrane
    Extraction-back-extraction Sample Pretreatment
    CAI Zeng-Xuan, CHEN Heng-Wu
    2006, 27(4):  638-640. 
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    This article presents the designing and fabrication of a microfluoidic chip with an integrated supported-liquid-membrane extraction-back-extraction and chip-based capillary electrophoresis system(SLMEBE-CCE).  A 3-dimensional channel network for the SLMEBE-CCE system was fabricated with a four-layer glass/PTFE-membrane hybrid structure.  With a gravity pump for sample and back-extraction solution delivery and  a multi-channel high-voltage supply for CCE separation,  the microchip with the coupled SLMEBE-CCE system was demonstrated by the pre-concentration, separation and detection of a mixed solution of fluorescein and butyl-rhodamine B.  Compared to chip-based CCE without SLMEBE, the developed SLMEBE-CCE system produced a 7-fold increase in the signal of the model analyte of fluorescein and a 4-fold decrease in the signal of the model co-existing compound of butyl-rhodamine B.

    Construction, Expression and Characterization of Neuroglobin Mutants(F28Y, F106Y)
    ZHAO Chao, LI Lian-Zhi1, JI Hai-Wei, WANG Li, XU Tao, LIU Jin-Feng
    2006, 27(4):  641-645. 
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    Neuroglobin(NGB), a newly discovered member of the hemoglobin superfamily, display a hexacoordination His-Fe-His in the absence of external ligands. In order to investigate the role of phenyla1anines(F) near bishistidyl ligands, the two neuroglobin mutants(F28Y, F106Y) were constructed, expressed, purified and characterized. The electrospray ionization mass spectroscopy results showed that the molecular weight of the two mutants correspond with the theoretical values. The UV-visible spectra of oxidized and reduced F28Y and F106Y were in agreement with the wild NGB, but the oxidized F28Y′s Soret band had a 2 nm blue shift, which suggested that the two mutants still remain hexa-coordinated form. The obvious red shift of F28Y′s fluorescence emission peak(F28Y: 340 nm→347 nm) relative to the wild NGB indicated that the mutant protein′s fluorophores exposed to more polar environment. The circular dichroism spectra results showed that the percentage of α-helix in F28Y, F106Y decreased and the β-sheet occurred in F28Y, this is caused by the specific site of F28 which sites at the outside of hydrophobic pocket and near the solvent surface. Thermal stability is NGB>F28Y>F106Y, which reflects that F106Y is more unstable. This may be explained on the basis of the strong hydrophobic interaction between F106 and heme, and also the decreased interaction, enables the heme disassociate from the protein chain more easily.

    Interaction of  Glyceraldehyde-3-phosphate Dehydrogenase in S.cerevisiae with Mitochndrial Genome
    Maintenance Protein Mgm101
    XUE Dong-Hua, WANG Li, ZUO Xiao-Ming
    2006, 27(4):  646-650. 
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    MGM101 is involved in mitochondrial genome maintenance in yeast. Mgm101p is a protein required for the replication of mtDNA. By means of yeast two-hybrid, we screened a Schizosaccharomyces pombe cDNA library for clones encoding proteins that potentially interact with Mgm101p. We have isolated 15 mt-DNA-associated proteins in yeast. We had identified five individual clones with GPD1 coding for glyceraldehyde 3-phosphate dehydrogenase(GAPDH). The S. cerevisiae counterpart of the GPD1, TDH2 was cloned and examined for its possibility to be involved in mitochondrial genome maintenance. GFP tagging, subcellular fractionation followed by Western blotting analysis revealed that GAPDH, besides having a cytoplasmic location, was imported into mitochondria and had potential to interact with Mgm101p. These results suggest that GAPDH is likely a multifunctional protein and interacts with Mgm101p  in mitochondria, which is involved in the process mediated by mtDNA.

    Articles
    Research of 3-(4-Aminophenyl)-indolizine Derivatives asFluorescent Probes for Protons
    SHEN Yong-Miao, WANG Bing-Xiang, FENG Yu-Ying, SHEN Zhu-Ying, SHEN Jian
    2006, 27(4):  651-653. 
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    Fluorescent molecular probes and switches system plays an important part in molecular recognition. The study on fluorescent probes and switches of proton guest has been developing rapidly in recent years. The modular structure of fluorspaceramine is pointed out to be important according to the principle of photoinduced electron transfer(PET). Three derivatives of 3-(4-aminophenyl)-indolizine were synthesized for the design of fluorescent molecular probes for pH. The fluorescence spectra and fluorescence quantum yields of the compounds were examined. The present study suggests that 3-(4-aminophenyl)-indolizine derivatives 3a and 3b were appropriate to measure pH values in the range 2.1—4.2 by a ratiometric method that relies on fluorescence emission. It suggested that derivatives of 3-(4-aminophenyl)-indolizine could find useful applications as intracellular pH meters.

    Contents
    Interaction Between Three Cucurbiturils and  Hydrochloride Salts of 4,4′-Dipyridyl and Its Derivates
    MU Lan, XUE Sai-Feng, DU Ying, ZHAO Yun-Ji, ZHU Qian-Jiang, TAO Zhu
    2006, 27(4):  654-659. 
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    In this paper, the host-guest relationship between a general cucurbit[n=7]uril(Q[7]) or a new ellipsoid-hostsymmetric tetramethyl-cucurbituril(TMeQ[6]) with hydrochloride salts of 4,4′-dipyridyl(44) or N,N′-dimethyl-4,4′-dipyridyl(dm44) was  examined for confirming the interaction between cucurbituril(Q[6]) and these guests.  The experimental results revealed that Q[7] included the 4,4′-dipyridyl part of this kind of guests which were inclined in the cavity of Q[7].  The results based on  1H NMR technique, cyclic voltammetric method and UV absorption spectrophotometric measurement revealed that strong interaction was existed between TMeQ[6] and  guest 44 or dm44 and a one-dimensional assembled superamolecular could be formed.  1H NMR technique and cyclic voltammetric method showed  no obvious interaction between Q[6] with the guest 44 and its derivates, however, UV absorption spectrophotometric measurements revealed that kind of interaction of them did occur, comparing the structural characteristic of Q[6] to TMeQ[6], a one-dimensional assembled superamolecular could be also formed between Q[6] and guest 44 and its derivates.

    Articles
    Stereoselective Synthesis of Derivatives of Polyhydroxylated Pyrrolidines
    LI Xiao-Liu, TIAN Jun, XU Xiao-Ming, HOU Yin-Ju
    2006, 27(4):  660-665. 
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    The derivatives of polyhydroxylated pyrrolidines have exhibited a remarkable biological activity to inhibit glycoside-processing enzymes, and found a potential chemotherapeutic applications against diabetes, cancer, and viral infections including AIDS. And great attention has been attracted to the synthesis of their new derivatives and analogues. In this paper, some new derivatives of 5-membered azasugars with partially protected hydroxy groups, and their fluorinated ones were synthesized via the key intermediate of norbonyl like bicyclic acetal with D-xylose and D-glucose as the starting materials. The glycosylation of the synthesized partially protected azasugar and 1-methylenesugar was explored.

    Reviews
    Highly Efficient Synthesis of Three Natural Deoxynucleosides
    JI Qi, HUANG Fei, LI Jin-Liang, MENG Ji-Ben
    2006, 27(4):  666-668. 
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    Three natural deoxynucleosides were synthesized with a high stereoselectivity and good or excellent yield. In the preparation of 2′-deoxy-β-D-adenosine, glycosidations between 1-chloro-2-deoxy-3,5-di-O-(p-chlorobenzyl)-α-Derythro-pentofuranose and silylated adenine as well as adenine sodium salt were systematically studied. A simple synthesis route to prepare 2′-deoxy-β-D-adenosine without chromatography was developed, making 2deoxy-β-D-adenosine readily accessible in an industrial scale. High efficient synthesis of 2′-deoxy-β-D-cytidine and 2′-deoxy-β-D-thymidine were also achieved without chromatography by glycosidations between 1-chloro-2-deoxy-3,5-di-O-(p-chlorobenzyl)-α-D-erythro-pentofuranose and silylated bases via the similar procedure.

    Synthesis and Activity of Novel Sulfur-containing Peptidomimetic Inhibitors of Tumor Necrosis Factor
    WANG Ding, ZHANG Qi-Han, XU Jia-Xi
    2006, 27(4):  669-671. 
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    Tumor necrosis factor is one of the important cell factors, which can regulate pro-imflammatory. On the basis of the known and efficient peptidomimetic inhibitors of tumor necrosis factor as the leading compounds, novel sulfur-containing peptidomimetic inhibitors were designed and synthesized in a convenient and efficient manner. Bioassay results indicate that three of them showed some inhibition activity on sTNF-α secretion in HL-60 cells induced by lipolysaccharide, and two of them showed a good stability and inhibition activity.

    Articles
    Synthesis of Iron Nanoparticles by Microemulsion with Span/Tween as Mixed-surfactants for Denitrification of Nitrate in Water
    LI Tie-Long, JIN Zhao-Hui, LIU Hai-Shui, WANG Wei, LI Hai-Ying, HAN Lu
    2006, 27(4):  672-675. 
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    Recent studies have shown that zero-valent iron(Fe0) may potentially be used as a chemical medium in permeable reactive barriers(PRBs) for groundwater nitrate remediation, and due to the extremely high reactivity, denitrification of nitrate in groundwater using nanoparticles has received increasing interest in recent years. In order to fabricate iron nanoparticles with homogeneous spherical shape and narrow size distribution, we developed a simple and green approach for synthesizing iron nanoparticles. We modified the conventional methods by applying the microemulsion with Span 80 and Tween 60 as mixed surfactants. Water was then titrated into the octanesurfactant mixture and changes were observed by visual inspection and conductivity measurement and the information was used in developing a phase diagram. The maximum content of water in the W/O microemulsion and its appropriate forming condition of the microemulsion were found. And then the microemulsion system consisting of saturated Fe2+ solution was used to synthesize α-Fe ultrafine particles by reduction reaction. The nanoparticles were characterized by using the powder X-ray diffraction(XRD), transmission electron microscopy(TEM). The results show that the average diameter of the particle is about 80 nm. The reductive activity of the obtained iron nanoparticles were studied by the denitrification experiment of nitrate. And the results show that under the experimental conditions iron removed mostly 120 mg/L of nitrate within a period of 30 min. And the mass balance of nitrate reduction with nanoscale Fe indicates that endproducts mainly are ammonia and the probable formation of nitrogen gas species during reaction with the new prepared nanoscale iron without pH control.

    Contents
    Effect of Alloying Extent of Carbon Supported  Pt-Ru Catalyst on Its Electrocatalytic Activity
    CHEN Yu, TANG Ya-Wen, WU Wei, CAO Jie-Ming, LIU Chang-Peng, XING Wei, LU Tian-Hong
    2006, 27(4):  676-679. 
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    It was found that the carbon supported Pt-Ru catalyst(Pt-Ru/C) with the Pt-Ru particles with high alloying,  small average size and low relative crystallinity can be prepared in the aqueous solution with tetrahydrofuran(THF) using NaBH4 as a reductant for reducing H2PtCl6 and RuCl3 at  room temperature.  The electrocatalytic activity of the Pt-Ru/C catalyst for the methanol oxidation is much higher than that of the commercial E-TEK Pt-Ru/C catalyst with the similar average size and relative crystallinity,  but low alloying.  It is indicated that the alloying of Pt-Ru could significantly affect the electrocatalytic activity of the Pt-Ru/C catalyst for the methanol oxidation.  The Pt-Ru/C catalyst with high alloying can be obtained because THF and H2PtCl6 can form the complex leading to that the reduction potentials of H2PtCl6 and RuCl3 are closed in the aqueous solution with THF.

    Theoretical Studies on Hydrogenbonding Complexes of Melamine and Cyclotrione
    ZHU Liang-Liang, TENG Qi-Wen, WU Shi
    2006, 27(4):  680-683. 
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    Supermolecular complexes of melamine and cyclotrione derivatives were studied with AM1 and PM3 methods and the stabilization energy and relative enthalpy of formation were obtained. Electronic spectra and IR spectra of complexes were calculated by using INDO/SCI and AM1 methods based on AM1 geometries. It is indicated that the monomers form the dimmer via hydrogen bonds, leading to the decrease of total energy in the system, and electronegativity and steric effects of the substituents affect stabilization energy. UV absorptions of the complexes are redshifted compared with those of the monomers owing to the less LUMO-HOMO energy gap. IR frequencies of N—H bonds in the complexes are lessened due to the formation of hydrogen bonds.

    Rigorous Solution of a Moving Particle with One-dimensional Central Potential V(q)=Bq2+A/q2(A, B>0) in Quantum Phase Space Representation
    WEI Gong-Min, LU Li-Qiang, LI Qian-Shu
    2006, 27(4):  684-686. 
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    The eigenfunctions of the Schrdinger equation with the onedimensional central potential  V(q)=Bq2+A/q2(A, B>0) for a motion particle are solved within the framework of the quantum phase space representation established by Torres-Vega and Frederick. Then the quantum phase-space probability density functions are also discussed.

    Studies on Interaction of New Medicine of QuinoloneClass with HSA and BSA by Using Fluorescence Enhancement and Fluorescence Quenching Theory
    YANG Man-Man, XI Xiao-Li, YANG Pin
    2006, 27(4):  687-691. 
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    By using the two theoriesfluorescence enhancement and fluorescence quenching, we studied and compared the inter action of four kinds of Quinolone-class-medicines with HSA and BSA, then analysed deeply the binding speciality of medicine and albumin and usual characterization constants: dissociation constant, quenching constant, quenching efficiency, energytransfer efficiency, the distance between donor and accepter. About binding type of albumin with medicine, through the quenching experiment result of the four kinds of medicines with HSA and BSA, we found that this quenching action type caused by the binding of donor between acceptor was not determined by the oneselfbiomacromolecule BSA, but together determined by the molecular structure of BSA and medicine, donor and acceptor, and their match with each other.

    Oxidation Desulfurization from Fluid Catalytic Cracking Gasoline via Photocatalysis
    ZHAO Di-Shun*, LIU Cui-Wei, MA Si-Guo
    2006, 27(4):  692-696. 
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    Oxidation desulfurization via photocatalysis was investigated by using thiophene in xylol as the model compound, and hydrogen peroxide is used as the oxidant. The effects of hydrogen peroxide mass fraction, high shear agitation time, titanium dioxide mass on the desulfurization efficiency of FCC gasoline were also investigated. Under suitable conditions, the desulfurization rate of the model compound and of FCC gasoline can reach 80% and 59%, respectively. The conductivity and GC-FPD analyses show that the sulfurcontaining compounds are converted into the substance with a higher polarity.

    Preparation of CdS and ZnS/CdS Semi-conductor Nanocrystals Using Cadmium-contained Hydrotalcite Layered Compound as Template
    GUO Ying, LI Guo-Dong, ZHANG He, CHEN Jie-Sheng*
    2006, 27(4):  697-700. 
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    The layered double hydroxide(LDH) compounds Cd 0.7 Cr 0.3(OH)2(C12H25SO4)0.3·0.7H2O and Zn 0.5 Cd 0.25 Cr 0.25 (OH)2(C12H25SO4) 0.25 ·1.7H2O were synthesized. Using these compounds as the precursors, we prepared CdS and CdS/ZnS nanocrystals that are implanted and stabilized in the layer matrices of the two types of compounds via a gas/solid reaction. The size of the nanocrystals can be controlled and tuned by changing the Cd/Cr molar ratio in the precursor.

    Articles
    Influence of Interpenetration Degree on Initial Stage of Polymer Chain Crystallization
    ZHANG Zhu-Qing, YANG Xiao-Zhen
    2006, 27(4):  701-703. 
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    In the present study, crystallization at the initial stage of six polyethylene chains(each chain containing 600CH2 in backbone) was simulated by means of molecular dynamics. Since the initial structures possess different degrees of interpenetration, the effect of entanglements, which arises from the interpenetration, on the crystallization was examined. The result shows that the degree of the interpenetration in the initial structures does influence the initial stage of polymer chain crystallization: the less interpenetration, the more rapid orientation behavior, and the more perfect lamella is obtained.

    Synthesis and Optical Properties of ZnxCd1-xS∶Ag Nanocrystals
    2006, 27(4):  704-707. 
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    Water-soluble Ag doped  ZnxCd1-x  nanocrystals were synthesized by using MPA (3-mercaptopropionic acid) as stabilizer. XRD and UV-VIS spectra were used to confirm the formation of the alloyed structure. After Ag doping, a new luminescent peak was observed and the luminescent efficiency of the nanocrystals was improved greatly. Fluorescent spectra investigation showed that the increasing of the content of Cd lowered the conduction band of the doped nanocrystal. The alloyed nanocrystals show composition-tunable optical band gap energy and their emission can be tuned continuously in the range of 425 to 603 nm.

    Formation Mechanism of Selane from the Reaction System of Selenium,Carbon Monooxide and Water
    LI Jing, QU Yong-Quan, HAN Ke-Li, LU Shi-Wei, HE Guo-Zhong
    2006, 27(4):  708-710. 
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    A detailed mechanism for the formation of selane(H2Se) from Se-CO-H2O system in the presence of triethylamine was studied by density functional theory calculations at the B3LYP/6-31G** level. The solvent effect is assessed by the CPCM method at the same level. The calculations suggest that the reaction proceeds through three transition states with energies barriers of 45.4, 8.4 and 19.9 kJ/mol in solvent tetrahydrofuran, respectively. The intermediate compound [(HOOCSe-)·(Base·H+)], whose stability is close to that of the product, may coexist with amine salt of hydrogen selenide([HSe-]·[Base·H+]) and works as a reductant according to the results of theoretical calculations.

    Reviews
    INDO/CI Studies on Electronic Structure and Nonlinear Optical Properties
    of Bis(salicylaldiminatio) Schiff Base Compounds and
    Their Ni(Ⅱ) Complexes
    YAN Li-Kai, SU Zhong-Min, QIU Yong-Qing, ZHU Dong-Xia, WANG Yue,WANG Rong-Shun,
    2006, 27(4):  711-715. 
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    The geometries of bis(salicylaldiminatio) Schiff base compounds and their Ni(Ⅱ) complexes were optimized by using ab initio HF method at the 6.31G(d) basis set. On the basis of the stable structures, the electronic spectra of these systems were studied by INDO/CI method. The nonlinear optical(NLO)coefficients were calculated by ZINDO/SOS method. The results show that the hyperpolarizabilities(β and γ) were increased with the increase of the conjugated range. The β and γ values of compound 1 are 35.54×10-30 esu and -1.20×10-34 esu, respectively, but β and γ values of compound 4 in which the conjugated bridge is naphthyl ring are 5422×10-30 esu and -2.00×10-34 esu, respectively. Compound 5 in which the phenyl ring is introduced from the terminal has the largest NLO coefficient. The value of β increased significantly by introducing Ni(Ⅱ) into the complexes, the β value of complexes are 1.7—10.8 times larger than that of other compounds, the value of γ also increased to a different extent.

    Contents
    High Selectivity and Structure of Active Centre of Copper Colloidal Catalyst in Selective Hydration of Acrylonitrile to Acrylamide
    SUN Dao-Xing, XIA Shu-Wei, XIA Shao-Wu
    2006, 27(4):  716-720. 
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    The relationship between the high selectivity of catalysis and the structure of active centre of copper colloidal catalyst in selective hydration of acrylonitrile to acrylamide was studied. Colloidal copper particles were prepared by reducing copper(Ⅱ) chloride solution with the mixed solution of hydrazine hydrate and sodium hydroxide in the presence of stabilizer polyvinyl pyrrolidone(PVP). The copper colloids stabilized by PVP were used as the catalyst in selective hydration of acrylonitrile to acrylamide with a selectivity of 100%. Therefore, the character of colloidal copper catalyst is its high selectivity. According to the properties of defects on the surface of colloidal copper particles, the reasons of the high selectivity are analyzed: (1) The type of the active centre is singled. According to the theories of defect and experimental results, it is shown that the active centre of metal copper is not point defect, but the end point of dislocation. (2) The structure of the active centre is stable. The experimental results show that the colloidal copper particle have mechanical properties of high hardness and high strength, which keep the structure of active centre stability. Meanwhile, the size of the colloidal particles is 45 nm longer than that of particles, dislocation of which can exist stably. So the dislocation can exist stably on the colloidal copper particles. This further ensures the stability of the structure active centre. We also propose the view point that a proper size space is needed for active centre existing stably on the surface of the catalyst. This explains the reason that colloidal catalyst particles under a certain size will lose its catalytic activity.

    Articles
    Inactivation Efficiency of TiO2 on H1N1 Influenza Virus
    LIN Zhang-Xiang, LI Zhao-Hui, WANG Xu-Xu, FU Xian-Zhi,YANG Gui-Qin, LIN Hua-Xia
    2006, 27(4):  721-725. 
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    In this paper the inactivation efficiency of TiO2 on H1N1 influenza virus under 365 nm UV illuminations was reported. Hemagglutination tests were used to determine the change of the titer of H1N1 and TEM were used to observe the deformation of H1N1 during photocatalysis. TiO2 photocatalysts were prepared by a modified sol-gel method and characterized by XRD, BET and Zeta potential measurements. The dependence of inactivation efficiency on dosage, calcinations temperature and surface charge state of the photocatalysts was investigated. The results show that TiO2 calcinated at 400 ℃ had the best performance and the surface charge state of the photocatalysts could influence the inactivation efficiency significantly. TEM micrographs reveal that H1N1 was attacked at its surface projections and it could be decomposed and mineralized for a longer photocatalytic treatment.

    Contents
    Catalytic Oxidation Cataluminescence of Ethanol over Catalysts Ce 1-x ZrxO2
    YE Qng, GAO Qi, ZHANG Xin-Rong, XU Bai-Qing
    2006, 27(4):  726-730. 
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    Cataluminescent characteristics of Ce 1-x ZrxO2(0 ≤x ≤1) nanoparticles in the catalytic oxidation of ethanol was studied with focus on the effects of the chemical composition, phase structure and the reaction temperature. To understand the relationship between the cataluminescence and catalytic performance of the Ce 1-x ZrxO2nanoparticles, catalytic ethanol oxidation was also studied in a conventional catalytic reactor under conditions similar to those for the cataluminescence study. It is shown that intensity of cataluminescence over Ce 1-x ZrxO2nanoparticles is associated with the rate of acetaldehyde formation.

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    FANG Yun, LIU Xue-Feng, XIIA Yong-Mei, ZONG Li-Yan
    2006, 27(4):  731-734. 
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    Articles
    Isopiestic Studies on Thermodynamic Properties for LiCl-Li2B4O7-H2O System at  298.15 K
    YANG Ji-Min, YAO Yan, ZHANG Ai-Yun , SONG Peng-Sheng
    2006, 27(4):  735-738. 
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    The isopiestic molalities and the water activities were measured at 298.15 K for the LiCl-Li2B4O7-H2O system by isopiestic method,  and the vapor pressures and the osmotic coefficients were obtained from the measurements. The experimental data were  represented by different forms of the ion interaction model based on the primary Pitzer model of osmotic coefficient.  The Pitzer ion interaction parameters were evaluated from recent measurements by using multiple regression and iterative method. The activity coefficients of LiCl and Li2B4O7-H2O  for the system LiCl-Li2B4O7-H2O were calculated by the ion interaction model parameterized at low concentrations. The  data of osmotic coefficients measured  are in reasonable agreements with those calculated by using the model. These studies are useful to improve the thermodynamic model for salt lake brine systems containing lithium and borates.

    Contents
    Synthesis of Sodalite in Roomtemperature Ionic Liquid
    MA Ying-Chong, XU Yun-Peng, WANG Shao-Jun, WANG Bing-Chun, TIAN Zhi-Jian, YU Jia-You, LIN Li-Wu
    2006, 27(4):  739-741. 
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    The simplest zeolite, sodalite(SOD), was synthesized iononic liquidthermally from aqueous basic aluminosilicate precursor gels in an imidazoliumbased ionic liquid, with 1-ethyl-3-methylimidazolium bromide as solvent. The synthesis was carried out at a temperature between 50 and 150 ℃ at an ambient pressure. The effects of mass ratios of aqueous gel to ionic liquid, molar ratios of n(Si)/n(Al) in gel and crystallization temperature and time on the crystallization were investigated. The morphology and structure of the as-prepared products were characterized by X-ray diffraction and scanning electron microscopy. The results show that a mixture of sodalite and zeolite X was initially precipitated in ionic liquid at a ratio 1∶3 of aqueous gel to ionic liquid, and finally transformed in to pure sodalite as the crystallisation time is prolonged, and the crystallinity of sodalite increased with the increase of n(Si)/n(Al) from 1.1 to 10. Increasing the ratio of aqueous gel to ionic liquid, zeolite X was favorable to crystallize, and it became the only product under the hydrothermal condition.

    Reviews
    Aligned Carbon Nanotubes Synthesized by Three-step Raising Temperature Method
    CAO Pei-Jiang, ZHU De-Liang, MA Xiao-Cui, PAN Yue-Wu
    2006, 27(4):  742-744. 
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    In a single-temperature furnace with the simple structure, three-step raising temperature process was used   to fabricate  aligned carbon nanotube film  with a large-area(7 mm×15 mm) by pyrolysis of ferrocene/melamine mixtures on silica. SEM(scanning electron microscopy)  and LR-TEM(low-resolution transmission electron microscopy) images show that these nanotubes have uniform outer diameters of about 22 nm and varying lengths from 10  to 40 μm. Each carbon nanotube is composed of many periodic structures with the same orientation. HR-TEM(high-resolution transmission electron microscopy) image shows that these periodic structures are made of 3\_20 graphene layers. XPS(X-ray photoelectron spectroscopy)  spectra show that carbon nanotube grows in a top growth mode. The EELS(electron energy-loss spectroscopy)  spectrum shows that these nanotubes are pure carbon tubes.

    Articles
    Crystallization Behavior of Poly(L-lactide)
    HE Yong, GAO Zhao-Fen, XIN Yan, YU Ying, LI Su-Ming, FAN Zhong-Yong
    2006, 27(4):  745-748. 
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    Melt-crystallization behavior of poly(L-lactide) (PLLA) synthesized by Zn metal was investigated by using DSC, WAXD and POM. The crystallization behavior from the melt was investigated in the range from 368 to 398 K. The thicknesses of lamellae was (14±1) nm, and the thickening effect was not obvious. The results were treated with Avirami equation and Arrhenius equation. Avrami index n  is 3±0.3 which means that spherulites morphology of PLLA crystals formed in the temperature range; A maximum in the crystallization kinetics was observed around 378 K; half time of crystallization at 378 K was about 5.2 min. Lauritzen-Hoffmann(LH) theory was used to investigate the crystallization mechanism of PLLA, presenting the transition from regime Ⅱ to regime Ⅲ is approximately 380 K. The values of Kg(Ⅱ)  and Kg(Ⅲ) were 4.57×105 K2 or 1.115×106K2, respectively. And Kg(Ⅲ)/Kg(Ⅱ)=2.44, which accords with the value forecasted by LH theory.

    Interior Morphology and  Structure of Expended Tussah Silk Fiber
    SUN Deng-Feng, SHAO Zheng-Zhong, CHEN Xin
    2006, 27(4):  749-752. 
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    The interior  morphology and structure of the  expended tussah silk fiber were studied carefully by scanning electron microscopy(SEM) and with the help of Raman spectroscopy,   attenuated total reflection-Fourier transform infrared(ATR-FTIR) spectroscopy and   X-ray diffraction(XRD). Meanwhile,  the thermal and mechanical properties of such kind of silk were also  investigated. The results indicate that the molecular chain of silk protein in the expanded tussah silk fiber was highly oriented,  in which the conformation was dominated by β-sheet. The well-performed silk fiber was made of many band-shaped micro-fibers aligned along its long axis.

    Viscoelastic Relaxation and Phase Morphology of Linear Styrene-butadiene-styrene Triblock Copolymer
    DU Miao,YU Qiu-Ming,WANG Wan-Jie,ZHENG Qiang
    2006, 27(4):  753-757. 
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    Phase behavior and viscoelastic relaxation of styrene-butadiene-styrene triblock copolymer(SBS) were investigated. Through the TEM observation,  it can be found that there exist cocontinuous phases in the SBS and the dimension of each phase can be confirmed. The DSC test reveals that the heating history that samples exposed to have a significant effect on SBS phase structure,  especially for PS phase with a small mass proportion in SBS. There is an order-disorder transition with temperature increasing,  and the transition temperature is considered to be related to the size of PS domain. The dynamic rheological measurements were conducted to evaluate the viscoelastic relaxation behavior of SBS triblock copolymer at different temperatures. Three relaxation peaks  appearing on the  temperature dispersion curve of  dynamic loss tangent at different frequencies is attributed to the relaxation of various motorial unit of SBS. Differing from PS homopolymer,  with the increase of temperature,  SBS still presents a  high elastic modulus because of the interaction between PS and PB phases,  and the entanglement of PB chains. Furthermore,  an obvious peak as shown in the dynamic frequency sweep curves is involved in the order-disorder transition when the temperature is beyond 98 ℃.

    Synthesis of  P(MMA-b-MAA) Amphiphilic Block Copolymer  and  Its Self-organization Behavior in Solvent
    WANG Ying, WANG Chang-Ming, YANG Bai
    2006, 27(4):  758-760. 
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    Using ethyl 2-bromoisobutyrate as the initiator, CuCl/α-α′-bipyridine(BPy) as the catalyst and ligand, the poly(methyl methacrylate) with single-caped halogen(PMMA-Br) was synthesized by atom transfer radical polymerization(ATRP). Then using PMMA-Br as the macroinitiator and CuCl/BPy as the catalyst and ligand, the block copolymer P[MMA-b-Pb(MA)2] was synthesized. After putting the copolymer P[MMA-b-Pb(MA)2] dip in hydrochloric acid for one day, the amphiphilic copolymer P(MMA-b-MAA) with a low polydispersity was synthesized by ion exchange. Then P(MMA-b-MAA) was dissolved in DMF followed by dialyzsis in deionized water, the nanoaggregate  of P(MMA-b-MAA) comes into being. All products were characterized by FTIR, GPC, NMR and SEM. The results show that the amphiphilic copolymer containing carboxylic block can be prepared though ATRP and ion exchange by introduction of  a new monomer containing metal ions,  lead dimethacrylate Pb(MA)2.

    Synthesis and Characterization of New Cyno-group Functionalized Ionic Liquids and Their Rheological Properties
    GONG Sheng-Min, MA Hong-Yang,WAN Xin-Hua,ZHAO Yong-Feng,HE Ji-Yu, ZHOU Qi-Feng
    2006, 27(4):  761-766. 
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    A series of cyno-group functionalized ionic liquids were synthesized and characterized by 1H NMR and elemental analysis. The density, melting point and solubility of the ionic liquids were affected by the length of substituted group and the chemical structures of anions. The rheological properties of the ionic liquids under steady, transient and dynamic state were studied with a rheometer over a wide range of temperature and frequencies. It was found that the ionic liquids studied could be considered as Newtonian fluids. Arrhenius equation was employed to describe the relationship between the viscosity and the temperature. The viscous flow activation energy of the ionic liquids calculated was changed regularly with the length change of alkyl substituent. Under transient state condition, the shear stress and viscosity of the ionic liquid 1-butyl-3-(β-propanenitrile) imidazolium hexafluorophosphate, as an example, kept constant with the change of time while the shear speed was fixed. However, a decreasing trend was observed when the temperature was increased. The dynamic rheological properties of this ionic liquid were also studied. The complex viscosity and loss modulus were also decreased with increasing temperature.

    Micellization of Poly(L-alanine)/Poly(ethylene glycol) Block Copolymer
    ZHANG Guo-Lin, MA Jian-Biao, WANG Yi-Nong
    2006, 27(4):  767-770. 
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    Block copolymers of poly(L-alanine)/poly(ethylene glycol)(PAME) were synthesized by ring opening polymerization and their structures were characterized. The secondary structure was investigated by circular dichroism(CD). The micellization and critical micelle concentrations(CMC) of PAME in water were monitored by fluorescent probe technique. The diameter and distribution of micelles were characterized by DLS and its shape was observed by TEM. The results show that the poly(amino acid) segment of block copolymer chains existed as α-helical conformation in aqueous solution. The block copolymers of PAME-1 and PAME-2 could form spherical micelles at room temperature, whose diameter was about several hundred nanometer. The CMC of PAME-1 micelle was 1.99×10-5 mol/L,  which depends on the PLA content of the copolymers.

    Preparation of Conductive PPy Composites Under Supercritical Carbon Dioxide Circumstance
    LI Gang, LIAO Xia, SUN Xing-Hua, YU Jian, HE Jia-Song
    2006, 27(4):  771-774. 
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    Electrically conductive composites were prepared via the  chemical oxidative polymerization of pyrrole monomer in polystyrene(PS) and zinc neutralized sulfonated polystyrene(Zn-SPS) films under supercritical carbon dioxide(SC-CO2) circumstance. The strong swelling effect of SC-CO2 made polypyrrole(PPy) particles not only formed on the surface, but also incorporated into the film,  resulting in a homogenous structure and a relatively higher conductivity. By comparison, the composite prepared in aqueous solution shows a skin-core structure and a conductivity of 3 to 4 orders of magnitude lower than that of the former  due to the diffusion controlled process of pyrrole monomer. The percolation thresholds of PS/PPy and Zn-SPS/PPy composites are 6.2% and 2.7% of volume fractions of  PPy, respectively, much lower than a theoretically predicted value of 16%. Moreover, the conductive composites prepared under SC-CO2 circumstance show higher thermal stability, especially in the high-temperature region.

    FTIR Study on  Retrogradation Behavior of Cross-linked Starch
    WU Hang, RAN Xiang-Hai, ZHANG Kun-Yu, ZHUANG Yu-Gang, DONG Li-Song*
    2006, 27(4):  775-778. 
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    Crystallization Behavior of Polyethylene/Montmorillonite(MMT) Nanocomposites by in Situ Polymerization
    LI Min,HE Xiao-Feng,LIU Jing-Jiang,ZHANG Xue-Quan,SUN Guang-Ping,CAI Hong-Guang
    2006, 27(4):  779-783. 
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    The crystallization kinetics isothermally,  the melting and crystallization behavior of pure HDPE,  HDPE/MMT blends and HDPE/MMT nanocomposites prepared by in situ polymerization were investigated by DSC. The crystallinity,  linear growth rate of spherulites,  equibrium melting temperature and crystallization ability of HDPE are similar to that of its blends with MMT. However, the crystallinity and equibrium melting temperature of PE/MMT nanocomposites by in situ polymerization are higher than that of HDPE.  The linear growth rate of spherulites and crystallization ability of the crystals formed at the same undercooling degree are lower for HDPE/MMT nanocomposites in comparison with HDPE.  On the other hand,  they are much higher when the crystals crystallized from melt at the same temperature, tc,  for HDPE/MMT nanocomposite.  The lateral surface free energy,  σ,  of the developing crystals is the smallest for HDPE,  secondly it is for the HDPE/MMT blends,  the HDPE/MMT nanocomposites exhibit the largest σ and it increased gradually with increasing the content of MMT in these composites.

    Reviews
    Synthesis and Characterization of Amphiphilic Triblock Copolymers PAA-PHB-PAA
    ZHANG Xue-Qin, ZHENG Yun, YANG Hu, LIU Quan-Wei, XIE Hong-Feng, WANG Zhi-Li
    2006, 27(4):  784-786. 
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    A new biodegradable PtBA-PHB-PtBA triblock copolymer was successfully synthesized by ATRP method with Br-PHB-Br as macroinitiator, tert-butyl acrylate as monomer and CuBr/PMDETA as the catalyst system. Cleavage of the tert-butyl ether groups of the PtBA-PHB-PtBA triblock copolymer was then performed via hydrolysis with trifluoroacetic acid as the catalyst in dichloromethane to afford the amphiphilic PAA-PHB-PAA triblock copolymer. The hydrolysis is successful but trace tert-butyl ether groups still remain in the backbone. The molecular weight characteristics and chain structures were conformed by GPC and NMR, respectively. Because of hydrophilic and biocompatibility, the amphiphilic triblock copolymers have potential applications in the field of drug release.

    Deionized Mediated Anticoagulant Heparin/Chitosan Multilayer Films
    TAN Qing-Gang, LIN Quan-Kui, FAN De-Zeng, JI Jian, SHEN Jia-Cong
    2006, 27(4):  787-789. 
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    The influence of different pH values between assembly and application environment on  the surface properties of layer-by-layer assembled heparin and chitosan multilayer films was investigated. The high adsorption amount of cationic dye and  high wettability on the chitosan terminated multilayer films at high environment pH may indicate the  excess of free sulfate group existed  on the chitosan surface. Since the ionization degree of chitosan decreased with increasing of pH, the multilayer films assembled at low pH will lead to some excess free unpaired sulfate group in higher pH application environment, which paired with ionized amino group under prepared conditions. The blood-compatibility tests performed with these films clearly demonstrated that the good anticoagulant activity of low pH assembled heparin/chitosan even on the chitosan-terminated surface. Such an easy and controlled processing by the difference of pH values between assembly and application environment may have a good potential for fabrication of biomedical device coating.

    Surface Structure and Properties of Fluorocopolymers Studied by XPS and Contact Angle
    ZHANG Qing-Hua, LIU Long-Xiao, CHEN Feng-Qiu, ZHAN Xiao-Li
    2006, 27(4):  790-792. 
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    The surface composition and properties of the copolymer miniemulsions containing fluorinated acrylate(FA) were investigated by X-ray photoelectron spectroscopy(XPS) and contact angle measurements. The surface energy of these copolymers was calculated by the harmonic equation from the static contact angles. The surfaces of the copolymers are very hydrophobic even with a low content of FA due to the surface enrichment of FA segments. The surface energy of copolymers decreases drastically with the increase of FA content and can reach 11.6 mN/m when the concentration of FA in copolymerization increases to 17.54%. The element composition and surface segregation of the fluorinated component as a function of depth of fluorocopolymer thick films were investigated by angle-dependent XPS. The content of fluorine on the surface of copolymers was higher than the calculated value according to the feeds. Our analyses  demonstrate that the side groups containing fluorine tend to enrich on the copolymer-air interface. The surface segregation is enhanced when the samples are annealed, which results in further decrease of surface energy.