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Table of Content

    10 May 2005, Volume 26 Issue 5
    Articles
    Preparation of Ion Exchange Mesoporous Sieve DEAE-SBA-15 and Its Application to Separation and Purification of Der f 2 Allergen in Dermatophagoides Farinae
    LEI Jie, ZHANG Lu-Yan, DING Sheng-Song, JIANG Shi-Yi, YU Cheng-Zhong, ZHAO Dong-Yuan
    2005, 26(5):  793-796. 
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    Mesoporous silica SBA-15 was functionalized by 2-diethylamino-ethanol(DEAE) through the (epoxide) ring opening of 3-glycidyloxy-propyl-trimethoxy silane grafted on the silica surface(denoted as DEAE-SBA-15). Subsequently, DEAE-SBA-15 was used as the weak anion exchange matrix for chromatography to purify (Der f 2) allergen from the spent culture medium extract of Dermatophagoides farinae, one of House dust mites that can cause heavy atopic diseases such as asthma and dermatitis. The structure of DEAE-SBA-15 was confirmed by 13C and 29Si CP MAS NMR and other methods. By SDS-PAGE, Der f 2 was estimated to have a molecular weight of 14 000 and appeared as the only separated protein band. The assay results of skin prick test showed that the allergic activity of Der f 2 was retained. The above results indicate that DEAE-SBA-15 materials are promising fixed-matrix candidates in liquid chromatography to purify proteins.
    Preface
    Hydrothermal Synthesis and Crystal Structure of a New Bimetallic Oxide Cluster Constructed from β-Octamolybdate and Copper(Ⅰ)-organonitrogen Complexes
    HE Jiang-Hua, YU Ji-Hong, PAN Qin-He, CHEN Peng, XU Ru-Ren
    2005, 26(5):  797-800. 
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    A new bimetallic oxide cluster [5-(4-Br-Ph)-2,4'-Hbpy]2[Cu(5-(4-Br-Ph)-2,(4'-bpy)2]2·)[Mo8O26] (1) was hydrothermally synthesized and structurally solved by single-crystal X-ray diffraction analysis. Crystal data for compound 1: monoclinic, P21/c, a=1.441 1(3) nm, b=(1.392 4(4)) nm, c=2.518 3(5) nm, β=99.06(3)°, V=4.990 3(17) nm3, and Z=2. The structure of compound 1 consists of a cluster anion {[Cu(5-(4-Br-Ph)-2,4'-bpy)2]2[Mo8O26]}2-, which is constructed from β-octamolybdate subunit (Mo8O26)4- covalently bonded to two coordinated complexes {Cu(5-(4-Br-Ph)-2,4'-bpy)2}+. Discrete protonated ligand {5-(4-Br-Ph)-2,4'-Hbpy}+ acts as the charge-compensating cation.
    Articles
    Synthesis and Biodistribution of a Cyclic Peptide Containing NGR Motif as a Potential Tumor Angiogenesis Imaging Agent
    ZHANG Tao, WANG Yi, CHU Tai-Wei, LIU Xin-Qi, HU Shao-Wen, WANG Xiang-Yun
    2005, 26(5):  801-805. 
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    In order to evaluate the potency of short peptides containing NGR motif as the imaging agents for diagnosis of tumor angiogenesis, a preliminary investigation on the synthesis and biodistrubution of a short peptide containing the NGR motif was carried out and the results are reported in the present paper. The open-chain peptide GGCNGRC was first cyclized to GG(CNGRC) by oxygen oxidation, and then coupled with benzoyl-protected N-hydroxysuccinimidyl-MAG3 to form Bz-MAG3-GG(CNGRC). The latter was labeled with 99mTc by reduction-ligand substitution procedure, while the benzoyl group was removed simultaneously. The labeled complex 99mTc-MAG3-GG(CNGRC) was isolated by HPLC and purified by reverse-phase sep-pak column. Its radiochemical purity was estimated to be better than 90%. The complex was stable in saline and serum. The biodistribution of 99mTc-MAG3-GG(CNGRC) in normal and tumor-bearing mice indicates that it is quickly distributed to the whole body and excreted via both hepatobiliary tract and kidney-urethra systems. 99mTc-MAG3-GG(CNGRC) was accumulated in zenografted colon carcinoma (CL-187) after 3 h post injection. It is expected that the radiolabeled short peptides containing NGR motif may be useful as diagnostic imaging agents for tumor angiogenesis.
    Preface
    Growth Mechanism of Zeolite NaA Membranes and the Thickness Control of the Membrane by Secondary Synthesis from Clear Solutions
    ZHANG Xiong-Fu, LIU Hai-Ou, King-Lun Yueng, WANG Jin-Qu
    2005, 26(5):  806-810. 
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    The Effect of the water content on the growth of NaA zeolite membranes and the thickness control of the membrane were studied by secondary synthesis from clear solutions. The samples were characterized by SEM, TEM and XRD. It has been shown that different synthesis solutions resulted in the different growth process of NaA zeolite membranes. In the dilute synthesis solution [n(H2O)/n(SiO2)=(2 000)], the thinner NaA membrane with single-layer structure was formed by zeolite crystals growing only within the seed layer. On the contrary, in the concentrated synthesis solution ([n(H2O)/n(SiO2)=750],) the thicker NaA membrane with two-layer structure was formed by zeolite crystals growing outward from the topmost layer of the seeds. As the n(H2O)/n(SiO2) ratio was decreased from 1 500 to 500, the membrane thickness was increased from 1.7 μm to 10.8 μm. These results show that the membrane thickness could be easily adjusted mainly by varying the water content of the synthesis solution.
    Articles
    Preparation and Characterization of BCN
    BAI Suo-Zhu, YAO Bin, HUANG Bao-Kun, ZHANG Shi-Jing, DING Zhan-Hui, GUO Xing-Yuan, ZHOU Xiang-Dong, SU Wen-Hui
    2005, 26(5):  811-815. 
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    Formation, structure and phase transition of BCN compound were investigated by mechanical milling of mixture of graphite and hexagonal boron nitride or annealing the as-milled mixture at high temperature and high pressure. Amorphous BCN(a-BCN) was prepared by milling the mixture for 120 h. A broad and strong absorbed peak locating at 1 400 cm-1 and two weak peaks locating at 740 and 1 630 cm-1 respectively were observed in the infrared spectrum of the a-BCN, and a broad (Raman) scattering peak was found at 1 330 cm-1 in its Raman spectrum. The binding energies of the (a-BCN) are 191.9 eV for B1s, 284.9 and 286.8 eV for C1s, 398.3 and 400.5 eV for N1s, respectively. (A hexagonal) BCN(h-BCN) with lattice constants of a=0.250 5 nm, c=0. 666 4 nm was produced by annealing the a-BCN for 45 min at 1 473 K and 4 GPa. Its infrared absorbed peaks appeared at 1 398, 1 103, 1 024, 925 and 802 cm-1, respectively, and Raman scattering peaks are observed at 1 328, (1 358), 1 582 and 1 614 cm-1, respectively. The mechanisms of the formation and phase transition of the BCN compound are discussed.
    Synthesis and Biodistribution of (99m)Tc Salicylidene Schiff Base Complex
    WANG Ming-Zhao, MENG Zhao-Xing, PENG An, TAN Xin
    2005, 26(5):  816-818. 
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    One novel complex of (99m)Tc-salicylidene-tyrosine Schiff base was designed and synthesized, and its biodistribution was investigated. The theoretical simulation revealed that the cis-and trans-(isomers) might co-exist in aqueous solution. A yield higher than 90% under the optimal condition of synthesis was obtained. Good water-solubility was demonstrated. Very little uptakes in muscle, brain, heart and S-180 sarcoma, as well as very rapid blood clearance were revealed in mice. Good accumulation in bone was shown. At 1 h postinjection the bone uptake was 10.9%ID/g. At 3 and 5 h postinjection, bone-to-muscle ratios were 19.0 and 9.3, and bone-to-blood ratios were 31.6 and 28.9, respectively. The result indicates a bone imaging potency of the complex.
    Hydrothermal Synthesis and Characterization of a Manganese(Ⅱ)-substituted Aluminum Phosphate Mn3Al6(PO4)12·4tren·11H2O with 12-Membered Ring Channel Open Framework
    SHI Lei, LI Ji-Yang, DUAN Fang-Zheng, YU Ji-Hong, LI Yi, XU Ru-Ren
    2005, 26(5):  819-821. 
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    A three-dimensional manganese(Ⅱ)-substituted aluminum phosphate, Mn3Al6(PO4)12·4tren·11H2O[tren is tris(2-aminoethyl)amine], was synthesized hydrothermally. Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by X-ray powder diffraction, ICP, TG analyses and magnetic susceptibility measurements. It crystallizes in the cubicsystem, space group I-43m(No. 217) with a=1.683 51(4)nm, V=4.771 4(2) nm3, Z=2, R1=0.043 9 and wR2=0.132 4[I>2σ(I)]. The open framework built up from strict alternation of TO4/AlO4 and PO4 tetrahedra through corner-sharing vertex oxygen atoms. It contains 12-membered ring channels. The Mn atoms of the framework are bivalence proved by magnetic susceptibility measurements.
    Solvothermal Synthesis of Nano-sphere-like La2O2S∶Eu3+ Phosphor
    KUANG Jin-Yong, LIU Ying-Liang, ZHANG Jing-Xian, YUAN Ding-Sheng
    2005, 26(5):  822-824. 
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    Nano-sphere-like Eu3+ activated lanthanum oxysulfide phosphor was first synthesized directly by solvothermal method. The phosphor was characterized by XRD, TEM and PL. Photoluminescence spectra indicate that this phosphor showed three typical transitions of Eu3+(5D07F1, 5D07F2, (5D07F4).) In comparison with those prepared by high temperature solid state method, photoluminescence spectrum of Eu3+(5D07F2)-doped nano-La2O2S∶Eu3+ phosphor became broader. And the reaction mechanism was also mentioned in this paper.
    Determination of Trace Zn~(2+) by Capillary Electrophoresis with Field-amplified Sample Injection and High Voltage Contactless Conductivity Detection
    TAN Feng, YANG Bing-Cheng, GUAN Ya-Feng
    2005, 26(5):  825-828. 
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    Analysis of trace Zn2+ by capillary electrophoresis with field-amplified sample stacking(FASS) and high voltage capacitively coupled contactless conductivity detection(C4D) was presented. 2-(N-Morpholino) ethanesulfonic acid(MES)/histidine(His) was used as the separation electrolyte. The effects of MES/His concentration in the sample matrix, and the injection time on the effective stacking efficiency, and the concentration of the separation electrolyte on the sensitivity were studied. Zn2+ was dissolved in deionized water and separated in 10 mmol/L MES/His(pH=4.9) buffer. The C4D using FASS yielded sensitivity enhancement with respect to non-stacking injection mode in excess of three orders of magnitude(1.3×103) and a limit of detection(LOD) 5 nmol/L to Zn2+. There was a linear relationship between the response of peak area and concentration of Zn2+ in the range from 10 to 1 000 nmol/L(R=0.999 5). The method can be used for determination of Zn2+ of trace level.
    Nanoelectrode-patch Clamp Monitoring of Continual Single Living Vesicle Release
    WU Wen-Zhan, HUANG Wei-Hua, WANG Wei, WANG Zong-Li, CHENG Jie-Ke, ZHANG Rong-Ying, CHEN Yu, LIU Jie, ZHENG Cong-Yi, SHEN Chao
    2005, 26(5):  829-831. 
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    Carbon fiber nanoelectrode(tip diameter ca. 100 nm)-patch clamp was firstly applied to real-time monitoring dopamine release from single living vesicles of single Rat pheochromocytoma(PC12) cells with highly temporal and spatial resolution. It is first demonstrated that there are continual vesicle releases of dopamine at the same site in the active release zone, which play a main role in the exocytosis.
    Studies on Human Red Blood Cells by Micro-video CE System
    DAI Dong-Sheng, QI Li, YU Xiao, CHEN Yi
    2005, 26(5):  832-834. 
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    A micro-video imaging system on-line coupled with UV detection and capillary electrophoresis has been set up and used for the investigation of human red blood cells(hRBC). Both free and aggregated cells were observed via the imaging and the broad peak overlain by bar-like peaks measured from UV detection was shown responsible for the free migrated and aggregated cells, respectively. More importantly, fast measurement of cell mobility was achieved within one second using the image acquired and the calculated mobility data agreed with that of UV, giving a deviation of less than 7%. Further more, this micro-video system allows us to vividly observe the adsorption-desorption process. In a fused-silica capillary, about 10% of the human red blood cells were turned out to adsorb on the tubing surface, they left the surface after 0.04 s to 3.12 s, giving an average retarding time of less than 1 s. This causes a loss of migration mobility of 5×10-6 cm2·V-1·s-1. It was thought that this system be applicable to the study of adsorption of other types of molecules with some modification.
    Preparation of Silica-bonded Bovine Serum Albumin Chiral Monolithic Column for Enantiomeric Separation by Capillary Electrochromatography
    YAN Li-Juan, ZHANG Qing-He, ZHANG Wei-Bing, FENG Yu-Qi, ZHANG Li-Hua, LI Tong, ZHANG Yu-Kui
    2005, 26(5):  835-837. 
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    A silica-bonded bovine serum albumin(BSA) chiral monolithic stationary phase for capillary electrochromatography(CEC) was introduced. An inorganic-organic hybrid monolithic column was firstly prepared by sol-gel chemistry with homogeneously distributed aminopropyl groups throughout the silica matrix. Then the chiral stationary phase was synthesized by the in situ covalent immobilization of BSA on the monolithic column activated with glutaraldehyde. The effects of pH value and concentration of phosphate buffer on the separation of D,L-tryptophan were investigated. The separation factor of D,L-tryptophan reached 3.37 on CEC mode.
    Fabrication and Electrochemical Characterization of Submicrometer Interdigitated Ultramicroelectrode Arrays
    ZHU Ming-Zhi,, JIANG Zhuang-De, JING Wei-Xuan
    2005, 26(5):  838-840. 
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    A gold submicrometer interdigitated ultramicroelectrode array(IDA) was fabricated by conventional photolithographic patterning of multilayered materials. The IDA structure, which consists of 50 pairs of fingers and has 1.5 mm finger length and 362 nm functional band width, is fabricated in a small region(1.5 mm×2.3 mm) on a quartz substrate. The electrode surfaces are inside the (trenches). Gold film thickness is the electrode width that is exactly measured by atomic force microscopy(AFM). The surface topographies of gold film and substrate are characterized by AFM for the study of the variation of electrode width. Scanning electron microscopy(SEM) is used to visualize the quality of fabrication and to measure the fingers. Electrochemical properties of IDA electrodes are investigated by cyclic voltammetry through three-electrode system. It is shown that IDA electrodes can be used as the disposable ultramicroelectrodes of chemical and biologic sensors.
    Preparation and Voltammetric Characterization of DNA Modified Electrode with Ethylenediamine as Arm Molecule
    JIAO Kui, XU Gui-Yun, ZHANG Xu-Zhi, MI Chun-Hua
    2005, 26(5):  841-843. 
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    Carboxyl was formed on the surface of glassy carbon electrode(GCE) by electrochemical oxidation. Ethylenediamine(En) was used as the arm molecule to link carboxyl with dsDNA using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride(EDC) and N-hydroxysuccinimide(NHS) as the activators to prepare dsDNA modified electrode(dsDNA/En/GCE). It was shown that dsDNA could be covalently immobilized on the surface of GCE. ssDNA modified electrode(ssDNA/En/GCE) was obtained via the thermal denaturation of dsDNA/En/GCE. The dsDNA/En/GCE and ssDNA/En/GCE were characterized by voltammetry with methylene blue(MB) as the indicator. The results indicated that the currents of the redox peaks of MB at ssDNA/En/GCE were larger than those at dsDNA/En/GCE, and the currents of the redox peaks at En/GCE were the smallest. The peak-currents of MB at the DNA modified electrode had good reproducibility after multi-denaturation and hybridization cycles.
    Effect of Temperature on Sensing Performance of Optical Fiber Relative Humidity Sensor Based on Nafion-crystal Violet Film
    JIN Xing-Liang, JING Miao, ZHAO Ying, WANG Zhuang-Xiong, ZHOU Kai, LI Wei, ZHUANG Zhi-Xia, WANG Xiao-Ru
    2005, 26(5):  844-845. 
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    The optical fiber relative humidity sensor based on Nafion-crystal violet film was developed. The effect of sample's temperature in the range from 299.15 K to 324.15 K on the sensing performance of the sensor was investigated. The mathematical function between temperature and the sensitivity of the sensor was established according to the reactive theory of sensor to the relative humidity, which was validated with the experiment. With the research, the application range of the sensor was extended, which made the sensor keep a good veracity when it was used in situ.
    Analysis of the Minimal Functional Promoter Region for hKv4.3 and Upstream Suppressors
    LI Hao, JIANG Chun-Lai, YU Xiang-Hui, WU Yong-Ge, LI Wei, KONG Wei
    2005, 26(5):  846-851. 
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    Activation(depolarization) and recovery(repolarization) of the heart is the result of the orchestrated activity of a variety of ion channels and transporters. Potassium currents such as the transient outward potassium current, Ito, contribute significantly to phase 1 of repolarization. hKv4.3 is the predominant gene that is believed to underlie Ito in the human ventricle. The regulation of hKv4.3 at the transcriptional level was examined by cloning its promoter region and associated negative regulatory elements. Serial deletions of the 5' flanking region identified the minimal promoter of hKv4.3 at-156 to +2 bp surrounding the transcriptional start site. The promoter is not cell type specific and lacks a canonical TATA box. Three motifs found within the promoter include an E-box(CANNTG), a CArG-box[CC(A/T)6GG], and a CACC-box. The CArG-box is necessary for transcriptional activity. A novel repressor element named T was identified. The deletion of the T element will at least double promoter activity.
    Separation, Purification and Structural Identification of Anti-tumour Compound in Trapa manshurica Fler
    NIU Feng-Lan, YIN Jian-Yuan, DONG Wei-Yan, WANG Xue-Dong
    2005, 26(5):  852-855. 
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    The anti-tumour compound in Trapa manshurica Fler was separated and purified by using the silica gel column chromatography, with an eluting agent of petroleum ether-ethyl acetate-formic acid(volume ratio is 5∶4∶0.1, Rf=0.4). The structure of compound Ⅰ obtained was identified to be 3,4,5-trihydroxybenzoic acid dimmer by means of MS, IR, 1H NMR and 13C NMR, and the preliminary study shows that it has a quite high activity for inhibiting the proliferation of hela cell induction apoptosis to anti-tumor mechanism by means of MTT[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] reduction method, optical microscope, transmission electron microscope and flow cytometry.
    Structure Analysis of Water Soluable Polysaccharide GIA Obtained from the Fruiting Body of Gloeostereum insarnatum
    WANG Shu-Sheng, LIU Dan, ZHOU Yi-Fa, LIANG Zhong-Yan, ZHANG Li-Ping
    2005, 26(5):  856-859. 
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    The water soluble crude polysaccharide was exacted by 6% carbamide from the fruiting body of Gloeostereum insarnatum. After the precipitation in ethanol and the filitration with Sepharose CL-6B gel, the fraction of GIA was obtained.By means of Sephadex G-75, HPLC and DEAE-Sephadex A-25, it was proved to be homogeneous on molecular weight and polar as well. The structure of GIA was determined by several methods. GC analysis results indicate that GIA is composed of the monosaccharide of xylose, galactose and glucose. The molar weight is estimated to be 18 000 by means of HPLC. Through IR, GC, partial hydrolysis with acid, periodate oxidation, Smith degradation, methylation, GC-MS and 13C NMR analysis, the results indicate that GIA has a kind of lowly branched structure.The main chain is mainly made up of major (1→6) galactose and (1→6) glucose, minor (1→3) galactose and (1→3) glucose. Residues are substituted at 6-O.On average, there are 2 branches among (10 main) chain residues. The side chain is composed of (1→3) galactose and (1→3) glucose. The nonreduced end is composed of xylose, galactose and glucose.
    An Efficient Approach to the Synthesis of Spiro-cyclopropane Derivatives Utilizing 4-Methoxy-2-bromobutyrolactone
    YU Zhao-Lian, LI Sen-Lan, GUO Jin-Bo, CHEN Qing-Hua
    2005, 26(5):  860-864. 
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    Cyclopropane-containing natural products have received considerable attention as the synthetic targets due to their significant effects on bioactivities with concomitant medical and agricultural implications. We recently reported a valuable synthetic route to spiro-cyclopropane-butinolied derivatives containing multiple stereogenic centers, using 5-L-menthyloxy-3-bromo-2(5H)-furanone, and different nucleophiles by tandem double Michael addition/internal nucleophilic substitution. On the basis of the previous work, the synthesis of 4-methoxy-2-bromobutyrolactone (4) was conveniently achieved from 4-hydroxybutyrolactone (2) as a starting material through the acetalization of methanol. 2-Bromobutyrolactone (4) as a synthon reacts with various nucleophiles under mild conditions to form the diversely functionalized spiro-cyclopropane derivatives 8a—8d via tandem double Michael addition/intramolecular nucleophilic substitution. Spiro-cyclopropane compounds 8a—8d were identified on the basis of their elemental analysis and spectroscopic data, such as IR, 1H NMR, 13C NMR and MS. The stereochemistry and configuration of the spiro-cyclopropane compound 8d was measured by X-ray crystallography. This result provides an efficient synthetic route to the interesting functionalized target molecules 8 with 4-methoxy-2-bromobutyrolactone (4) as a cheap substrate. It could be furnished further an important synthetic strategy for some complex cyclic natural and nonnatural products.
    Preparation, Structure Characterization and Properties of New Poly(vinyl alcohol) Microcapsules
    WANG Man-Yan, YU Yao-Ting, T.M.S Chang
    2005, 26(5):  865-869. 
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    Uremia is a very severe and wide spread disease, oral administration of microcapsulated genetically engineered E. coli is a better method for treating uremia than renal hemodialysis in terms of its high efficiency and low cost. In this paper, a new type of polyvinyl alcohol(PVA) microcapsules was prepared by using low temperature physical crosslinking method, which showed a strong mechanical strength, high chemical stability and low toxicity. Comparing with APA microcapsules that is currently used, PVA microcapsules has much higher mechanical strength. Moreover, the PVA microcapsules had a good permeability to small molecules such as urea, uric acid and creatitine, all of which can permeate through PVA microcapsules within 10 min. When the genetically engineered E. coli DH5 was entrapped to PVA microcapsules, the bacteria showed a high capacity for removal of urea, which was believed to be a key factor in the pathogenesis of uremia. Therefore, PVA microcapsules prepared by low temperature physical crosslinking method had a high potential for oral administration in the treatment of uremia patients.
    Mass Spectrometry Analysis of Recombinant Endostatin and Effect on Cell Cycle of Endothelial Cells
    WANG Qun, NI Jia-Zuan
    2005, 26(5):  870-873. 
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    The structure of recombinant endostatin and mechanism of acting on endothelial cell were studied by mass spectrometry, circular dichroism spectroscopy, fluorescence spectroscopy and cell cycle analysis technique. It was found that the recombinant protein prepared from inclusion body of E. coli may combinate the derivated protein with N-terminal Met. The mechanism by which recombinant endostatin causes G2 arrest in endothelial cells was observed, which demonstrated that the apoptosis of endothelial cell induced by endostatin was correlated with cell cycle. The results lay the foundation for the antiangiogenesis therapy of the tumor.
    Improvement of Selectivity and Cytotoxicity of IL-4 Immunotoxin on Lymphoma Through Site-directed Mutagenesis
    CUI Jing-Xia, JI Jian-Fei, LV An-Guo, WU Wen-Fang
    2005, 26(5):  874-879. 
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    A wide variety of human cancer cells such as glioma and lymphoma express interleukin-4 receptors(IL-4R), therefore, it may be a good option to treat IL-4R-bearing tumor with IL-4-containing immunotoxins. By software analysis, two important amino acids 13T and 121R of (IL-4) were chosen for site-directed mutation. Interleukin-4 mutein cpIL-4(13D121E) was obtained through overlapping PCR and the chimeric immunotoxin was constructed by fusion of the gene encoding cpIL-4(13D121E) to a gene encoding a modified Pseudomonas exotoxin A(PE38KDEL). The chimeric immunotoxin was expressed in E. coli with the yield of about 30% of the total bacterial protein. After being highly purified by affinity chromatography and anion exchange chromatography, the chimeric protein was tested for its cytotoxicity. The data show that cpIL-4(13D121E)-PE38KDEL had improved cytotoxicity to lymphoma cells Daudi expressing class Ⅰ IL-4R in comparison with other IL-4-containing immunotoxin and had a lower cytotoxicity to endothelial cells expressing class Ⅱ IL-4R.
    Asymmetric Synthesis of Natural Macrocyclic Diterpene(+)-Methyl Cembra-1,3,7,11-tetraene-16-carboxynate
    SUN Bin, MEI Tian-Sheng, LIU Zuo-Sheng, LI Yu-Lin, LI Ying, PENG Li-Zeng
    2005, 26(5):  880-882. 
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    The first asymmetric synthesis of (+)-methyl cembra-1,3,7,11-tetraene-16-carboxynate, a naturally occurring cembrane-type macrocyclic diterpene isolated from Sinularia mayi, was achieved via general approach by employing an intramolecular McMurry coupling and Sharpless asymmetric epoxidation as the key steps from readily available starting materials. The synthesis presented here verifies that the absolute configuration of compound 1 was assumed as 15R.
    Selective Isolation of 1,8-Cineole from Volatile Oil of Flos Magnoliae(Xin Yi) via Inclusion Crystalline
    GUO Wen-Sheng, GUO Fang, TONG Jian, CHANG Jian, CAI Yun-Ping, LIU Cheng-Yan, HOU Dong-Yan, HUI Rui-Hua
    2005, 26(5):  883-885. 
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    We used 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol(A) as the host molecule to selectively recognize the component 1,8-cineole(B) in the volatile oil of Flos Magnoliae(Xin Yi). The inclusion compound(A+B) was formed as crystalline, and the structure was confirmed by means of IR, (1H NMR), and single crystal X-ray diffraction, with the 1∶2 molar ratios of the host to the guest. The component 1,8-cineole(B) was selectively isolated from the inclusion compound(A+B) by Kugelrohr vaccum technology, and then further characterized by IR, 1H NMR and 13C NMR. The whole components in the volatile oil of Flos Magnoliae(Xin Yi) and the isolation effect of 1,8-cineole isolated from inclusion crystals were analyzed by GC and GC-MS, respectively. The result indicate that the good isolation effect is given by the inclusion method, with purity and yield of the component 1,8-cineole(B) separated from the volatile oil of Flos Magnoliae are 100% and 85%, respectively.
    Immune Effect of HBsAg Adsorbed by Nanoparticulate Alum adjuvant
    HE Ping, LV Feng-Lin, CHEN Yue, LI Yuan-Chao, HE Feng-Ci
    2005, 26(5):  886-888. 
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    We have synthesized a novel formulation of nanoparticulate(NP) alum adjuvant specifically in the cationic water-in-oil microemulsions of water/benzalkonium bromide(BB), octyl alcohol/cyclohexane at 30 ℃, which was characterized to be crystalline Al(OH)3 with average particle diameter about 70 nm by the analysis of X-ray diffraction and to have a spherical shape structure by TEM photography analysis. Then adsorption degree was assayed. The OD492 of the NP is about 10 times higher than the bulk(BK) alum adjuvant. Compared to bulk alum adjuvant, we studied the immune effect of the NP alum adjuvant with HBsAg vaccine, which was injected intraperitoneally into Guinea pig, and serum antibody titers of the first and second week after immunization were higher in NP group than BK group by ELISA(P<0.01, P<0.05); Groin immuno-injection intraperitoneally into Balb/c mice, was performed once or there times, prolife responses of spleen cells were determined by 3H thymidine incorporation; non-specific phagocytosis of macrophage of abdominal cavity was measured by lack of color Malachite Green and IL-2 was assayed by activation mouse spleen cells. It is indicated that all cellular immunity bioassay results were higher in NP group than in BK group, except non-specific phagocytosis of macrophage of abdominal cavity by there times immunity. However, there was no significant differerces. Thus, nanoparticulate alum adjuvant can be employed as a more effective adjuvant for HBsAg vaccine than bulk alum adjuvant in the earlier period of post-immunity.
    Synthesis and Combustion Catalytic Activity of Nanoparticle Pb(Ⅱ)-Resorcylic Acid Complex
    HONG Wei-Liang, LIU Jian-Hong, QIU Chao-Er, ZHAO Feng-Qi, TIAN De-Yu, ZHANG Pei-Xin, WANG Fang
    2005, 26(5):  889-893. 
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    The nanoparticle Pb(Ⅱ)-resorcylic acid complex were synthesized by liquid dispersion deposition method by using Pb(Ac)2·2H2O and resorcylic acid as the reactant, and characterized with TEM, XRD, TG, DSC, IR and element analysis. The effects of reactive condition on the particle size and the morphology of complexes were investigated. In addition, the catalytic activity of nanoparticle PbRes complex on the thermal decomposition of nitrocellulose-nitroglycerine(NC-NG) was also determined by DSC. The results show the spherical complex nanoparticles with a diameter of 50 nm were obtained in ethanol solution, and the stick-shaped complex nanoparticles with a diameter of 15 nm and length of 40 nm were obtained in H2O. The peak temperature of the thermal decomposition of NC-NG decreases by 5.6 ℃, and the decomposition enthalpy ΔH increases by 918 J/g(about 41%), in the presence of nanoparticle PbRes complex.
    Theoretical Studies on Molecular Structures and Stability of SiNP
    YU Jian-Kang, CHEN Guang-Hui, HUANG Xu-Ri, LI Zhuo, SUN Chia-Chung
    2005, 26(5):  894-896. 
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    The singlet and triplet potentical energy surfaces (PES) of SiNP are investigated at the B3LYP, QCISD and CCSD(T) levels. It is shown that there are seven stable isomers and four transition states located. The global minima is a linear triplet isomer SiNP-31, followed by a singlet cyclic isomer cSiNP-14 and a linear isomer SiNP-11, and all the above three isomers have good thermodynamic and kinetic stabilities.
    Structure and Activity of RuO2/γ-Al2O3 Catalyst Doped with CeO2 in Wet Air Oxidation Degradation of Phenol
    YANG Shao-Xia, FENG Yu-Jie, WAN Jia-Feng, CAI Wei-Min ZHU Wan-Peng, JIANG Zhan-Peng
    2005, 26(5):  897-901. 
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    In this paper, RuO2/γ-Al2O3 and RuO2-CeO2/γ-Al2O3 catalysts were prepared by the impregnation method. The structure of the catalysts was investigated by XRD, XPS and ESR. The catalytic activity was studied in the wet air oxidation(WAO) of phenol. The results show that the dispersion of RuO2 particles is higher on RuO2-CeO2/γ-Al2O3 catalyst than that on RuO2/γ-Al2O3 catalyst. There were oxygen deficiencies and chemisorbed oxygen on the surface of the two catalysts. Moreover, the amount of them increased after the addition of CeO2 into RuO2/γ-Al2O3 catalyst. RuO2/γ-Al2O3 and RuO2-CeO2/γ-Al2O3 catalysts have a good activity in WAO of phenol. At a mass concentration 4 200 mg/L of phenol, 150 ℃ and 3 MPa, phenol was totally removed after 150 min over RuO2/γ-Al2O3 catalysts, and the phenol removal ratio was 96% after a 60 min reaction over RuO2-CeO2/γ-Al2O3 in WAO.
    Preface
    Adsorption and Reaction Behavior over Co Catalysts Supported by Different Zirconia Polymorphs
    MA Zhong-Yi, YANG Cheng, DONG Qing-Nian, WEI Wei, CHEN Jian-Gang, LI Wen-Huai, SUN Yu-Han
    2005, 26(5):  902-906. 
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    CO and CO/H2 adsorption and reaction behavior over Co catalysts with amorphous, tetragonal and monoclinic zirconia as the supports were characterized by FTIR, TPSR and Fisher-Tropsch synthesis. The results show that cobalt catalysts with different zirconia polymorphs as the supports exhibited various behavior of CO adsorption and reaction. For the Co catalyst supported on monoclinic zirconia, besides the multi terminal CO, bridged and tribridged CO appeared and were easily dissocia-(ted) at a high temperature, which resulted in the higher catalytic behavior and C+<sub>5 selectivity in the case of CO hydrogenation. While for cobalt supported on tetragonal zirconia, the bridged CO was more stable and CO hydrogenation was relatively less active.
    Articles
    Density Functional Calculation and Monte Carlo Simulation of Solvating Effect of Tautomerism and Proton Transfer of 2-Amino-2-imidazoline
    XUE Ying, ZHANG Hui, XIE Dai-Qian, YAN Guo-Sen
    2005, 26(5):  907-911. 
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    The density functional theory and Monte Carlo simulation were used to study the tautomerism and proton transfer of 2-amino-2-imidazoline in the gas phase and in water. Two reaction pathways, the direct and water-assisted transfers, were considered. The optimized geometrical structures and thermodynamic properties of stationary points for the reaction system in the gas phase were calculated at B3LYP/6-311+G~(**) level of the theory. The study of solvating effect of water on the proton transfer of 2-amino-2-imidazoline indicates that water as the solvent is favorable for the water-assisted process and slows the rate of the direct transfer pathway.
    Effect of Wettability on Mass Transfer Performance of Hydrophobic Membrane Contactor
    LU Jian-Gang, WANG Lian-Jun, LIU Xiao-Dong, LI Jian-Sheng, SUN Xiu-Yun
    2005, 26(5):  912-917. 
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    A mechanism of wettability for hydrophobic membrane was presented based on bi-film theory. Resistance equation, Laplace equation and pore size distribution function of membrane were correlated, and a novel mass-transfer mathematical model was developed. The process of mass-transfer of CO2 absorption in membrane contactor was studied by using hydrophobic microporous PP membrane and absorbents of water or MDEA(N-methyldiethanolamine) aqueous solution. The effects of wettabilities engendered by pressure difference, surface tension and temperature on mass transfer were investigated. The results show that the model can be used to predict better the mass-transfer coefficients caused by wettability, and the predicted values are in good agreement with the experimental data; wettabilities caused by pressure difference, surface tension and temperature give rise to significant effects on mass transfer and should be taken into consideration in gas-liquid membrane contactor.
    Synthesis and Electrochemical Performance of Anodic Material Poly(p-phenylene) Polysulfide for Lithium Battery
    WANG Wei-Kun, WANG An-Bang, CAO Gao-Ping, YANG Yu-Sheng
    2005, 26(5):  918-921. 
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    In order to minimize the electrically nonconductive nature and capacity fade during cycling of sulfur in the anodic material of lithium batteries, a new method for modifying its structure was proposed in this paper. Poly(p-phenylene) polysulfides (PPPS) were synthesized whose skeleton was conducting poly(p-phenylene)(PPP) with polysulfur side lines attaching to it by chlorination of PPP and subsequent sulfuration of poly(p-phenylene) chloride(PPPCl). The resulted products were characterized by 13C NMR, IR spectrum, Raman spectrum and element analysis. The IR data of 461, 615 cm-1 and Raman data of 470 and 666 cm-1 suggested the existence of C—S and S—S bonds, which belong to the desired product PPPS. The electrochemical behavior of this material exhibited a high capacity of 987 mA·h/g at 80 mA/g and 776 mA·h/g at 400 mA/g, and its utilization efficiency was 83.5% and 66.7% respectively at the two current densities. The material also showed a stable reversible capacity of 307 mA·h/g after 25 cycles.
    Theoretical Study on the Structures and Properties of Group ⅢA Metallic Azide Clusters
    XIA Qi-Ying, XIAO He-Ming, JU Xue-Hai, GONG Xue-Dong
    2005, 26(5):  922-926. 
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    The DFT/B3LYP method with SDD basis set was used to study the structures and properties of the group ⅢA metallic azide clusters(Me2MN3)n(n=13; M=Ga, Al). (Me2MN3)2,3 clusters all possess cyclic-like structures formed by Ga or Al atoms bridged by the α-nitrogen of the azide groups. (Me2MN3)2 was found to exhibit the planar M2N2 ring structure.(Me2MN3)3 involving a six-membered M3N3 ring was found to exhibit boat-twisting and chair-like structures with very similar binding energies. Compared to the monomer, the structural changes for the clusters are large. Thermodynamic properties of the monomer and its clusters at different temperatures were discussed, which reveals that the dimethylmetallic azide clusters of aluminium and gallium consist of the dimer.
    Selective Electrochemical Synthesis of Ferrate on SnO2-Sb2O3/Ti Electrodes
    ZHANG Cun-Zhong, LIU Zhen, LIN Li-Jun, QI Fei, WU Feng
    2005, 26(5):  927-930. 
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    The electrode of SnO2-Sb2O3/Ti was manufactured in this research. The results prove that the electrochemical generation of FeO2-4 could be carried out on this kind of electrode in a 14 mol/L NaOH solution without any impact of the side reaction of oxygen evolution reaction(OER) under the same experimental condition. The results indicate that the dissoluble ion, FeO2- is one of existent formations of (Fe(Ⅲ) compounds), the ion is a reactant of the chemical oxidation and electrochemical oxidation, the redox couple is not FeO2-4/Fe(OH)3, but FeO2-4/FeO2- in the concentratied NaOH solution. The feebly amphoteric property of Fe(Ⅲ) compounds plays a considerable role in the manufacture of safety rechargeable batteries. Furthermore, the onset potential value of electro-oxidation of FeO2-(0.38 V vs. Hg/HgO, 14 mol/L NaOH) is close to that of electro-reduction of FeO2-4(0.54 V) under the same research condition. The results also indicate that the mechanism of electrochemical generation of FeO2-4 from FeO2- is an electro-chemical mechanism. In addition, the excellent stability of the SnO2-Sb2O3/Ti electrode was exhibited under the research condition.
    Temperature-denpendent FTIR Spectroscopy Phase Transition Process of Thin Films of Antiferroelectric Liquid Crystal
    CHENG Yu-Chuan, XU Wei-Qing, SUN Li, WANG Xu, ZHAO Bing
    2005, 26(5):  931-934. 
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    The conformation and orientation of the alkyl chain and the core of AFLC were studied by temperature-dependence spectroscopy. The conformation and orientation of the alkyl chain changed obviously as the temperature increased except the phase transition point between the S*IA and S*CA. Three CO stretching vibrational modes gave two different phase transition behavior. The phase transition between increasing and decreasing temperature was quite different, this is due to the influence of substrate.
    Synthesis and Photochromic Behavior of Spiropyran Dyes
    SHEN Kai-Hua, LI Xiao-Lian, CHOI Doon-Hong
    2005, 26(5):  935-938. 
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    A novel bifunctional dye containing spirobenzopyran and cinnamoyl moiety was prepared and its behavior following irradiation with different UV lights(275/365 nm) was investigated. The colourless bifunctional dye in the film state exhibits photochromism through the colored merocyanine transformation of spirobenzopyran and photocrosslinking reaction in cinnamoyl moieties. The dynamic processes of decolorization was investigated by using the PMMA and PVCi film. The effect of photocrosslink on the stability of photochromism was considered from this study.
    Direct Preparation of Patterned TiO2 Film with a Microstructure by Microcontact Printing Method
    ZHANG Rui, CHEN Miao, XUE Qun-Ji, GUAN Fei, LIANG Shan
    2005, 26(5):  939-941. 
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    A novel process to gain clear and high edge acuity micropatterns of TiO2 thin films by direct microcontact printing was presented in this paper. Using TiO2 sol as the “ink”, poly(dimethylsiloxane) elastomeric stamp was taken to transfer the TiO2 colloids to the substrate. The process is different from the traditional process using the SAMS to induce the deposition of TiO2. The new way increases the transferred efficiency of the micropatterned TiO2 thin films. The optical micrographs and SEM show that the micropatterned structures of TiO2 were microscale and uniform over a large area as well.
    Formation of Built-in Field of ZnO Nanoparticles and Effect on Its Optoelectronic Properties
    LIN Yan-Hong, WANG De-Jun, ZHAO Qi-Dong, LI Zi-Heng, WEI Xiao
    2005, 26(5):  942-944. 
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    The effect of built-in field on the surface photovoltage(SPV) response of ZnO nanoparticles was investigated by means of surface photovoltage spectroscopy(SPS). From the results of in situ SPS in atmosphere and in vacuum, we suggest that the built-in field should be a main condition for producing SPV response. By comparison of SPS with PL in vacuum as well as in atmosphere, we deduce that by changing the ambience of ZnO, its functional properties can be modulated.
    Mechanism of δ-FeOOH Formation by Oxygen Oxidizing Fe(OH)2 Suspension with EDTA Used as Cofactor
    WEI Yu, MENG Zhe, JIA Zhen-Bin, MA Zi-Chuan
    2005, 26(5):  945-947. 
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    At room temperature and in the presence of trace EDTA, the formation of δ-FeOOH was studied by the rapid oxidation of Fe(OH)2 suspension with O2. The structural and morphological changes were characterized by various techniques such as XRD, FTIR and TEM. γ-FeOOH and (δ-FeOOH) formed simutaneously in the early period of oxidation. But as the rate of mass transfer was in equilibrium, trace (γ-FeOOH) vanished gradually. Accordingly, pure phase δ-FeOOH was obtained. At the same time, critical amount ratio K of EDTA to Fe2+ was verified. The experiments show that the reactivity, rate of the oxidizing agent and pH of the initial medium were important factors for the formation of pure phase (δ-FeOOH). Under the auxiliary effect of EDTA, the reactivity of O2 was nearly improved to that of H2O2. And the process of the oxidation that Fe(OH)2 suspension was oxidized by O2 under that condition was discussed.
    Synthesis of Organic-inorganic Hybrid Nanocapsules by Using Low Molecular Weight Droplets as Template
    NI Ke-Fan, SHAN Guo-Rong, WENG Zhi-Xue
    2005, 26(5):  948-951. 
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    A novel nanocapsules were synthesized by miniemulsion polymerization the using low molecular weight droplets as the template. Styrene and 3-trimethoxysilyl propyl methacrylate(MPS), which contain vinyl and Si—OR groups, are copolymerized on the surface of the well dispersed isooctane droplets to form capsules. With the free radical copolymerization, the Si—OR groups can be hydrolyzed and condensed into Si—O—Si inorganic network. The diameter of the capsules is about 98 nm and the void fraction is about 70%. The morphology of the capsules was characterized by transmission electron microscopy, and the microstructures of the capsules were characterized by infrared spectrometry. The effects of the polymerization methods and monomer volume fraction on the morphology were discussed. It is found that the initial volume fraction of the monomer in the recipe must be lower than 36% to obtain capsules, and higher MPS volume fraction is favor in the formation of capsules, but a higher MPS content in capsules will lead to collapse. Finally, the mechanism of this synthetic process was interpreted by thermodynamic and kinetic analysis.
    Resistivity-temperature Properties and Resistivity Relaxation of Carbon Black Filled Poly(methyl vinyl siloxane) Vulcanite
    CHEN Yong-Liang, SONG Yi-Hu, ZHENG Qiang, ZHANG Ming-Qiu
    2005, 26(5):  952-955. 
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    The conduction behavior of carbon black(CB) filled poly(methyl vinyl siloxane)(PMVS) vulcanites undergoing thermal cycles or subject to thermal treatment at given temperatures was investigated. The conduction behavior in PMVS/CB crosslinked composites at room temperature followed the prediction of the statistical percolation theory. The negative temperature coefficient(NTC) effect of resistivity corresponded to thermal activation conduction mechanism, while the positive temperature coefficient(PTC) effect was related to the breakdown of conductive network caused by volume expansion. The results revealed that the resistivity-temperature properties during the thermal cycles was gradually changed towards low-resistance, while the change of resistance with variation of time at given temperatures exhibited resistivity relaxation behavior. The conductive mechanisms and corresponding changes in the structure of PMVS/CB responsible for the resistivity-temperature behavior were discussed. At given temperatures, the tesistance relaxation was strengthened with decreasing CB weight fraction. On the other hand, it is strengthened with increasing ambient temperature at given CB fractions.
    Studies on Crystalline Morphology of Poly(L-lactide)-Poly(ethylene glycol) Diblock Copolymers
    SUN Jing-Ru, ZHUANG Xiu-Li, CHEN Xue-Si, JING Xia-Bin
    2005, 26(5):  956-959. 
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    Crystallization behavior and morphology development in biodegradable diblock copolymers of poly(L-lactide)-poly(ethylene glycol)(PLLA-PEG) have been investigated by means of polarized optical microscopy(POM) and atomic force microscopy(AFM). At 110 ℃, PEG5000-PLLA2300 and PEG5000-PLLA6300 diblock copolymers formed banded spherulites, while PEG5000-PLLA12000 did not give banded spherulites. At 120 ℃, PEG5000-PLLA12000 formed banded spherulites, too, indicating that suitable undercooling is one of the key factors to get these banded spherulites. As a solvent and a diluting agent, the presence of PEG blocks brings about decrease in nucleation rate and increase in growth rate of the PLLA crystallization at around 110 ℃, resulting in larger spherulites. The surface of the banded spherulite is shown to consist of concentric ridges and valleys. At the ridges, PLLA lamellae were stacked in edge-on manner, while at the valleys, PLLA lamellae were stacked in flat-on manner.
    Aggregation of Anchored Polymer Chain on Surface by Molecular Dynamics Simulation
    HAN Ming, LI Ting, YANG Xiao-Zhen
    2005, 26(5):  960-963. 
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    The aggregation and ordering process of the anchored polyethylene on the infinite surface was stndied by molecular dynamics(MD) simulation. The surface potential function S(z) simulated here is relative to the distance z between the atom and the surface. Effect of the temperature and strength of the surface potential were characterized by the normal component of the mean square of the radius of gyration s2<sub>⊥. We studied the ordering process and nucleation of the anchored chain on the surface, the morphology of the globules and the process dependence on the molecular mass, in details. We found that the nucleation took place near the anchored point at 300 K. The anchored point lies in the side of the end-stems of the aggregation with various orientation degrees.
    Structure of Chemical Cross-linked Gel of Epoxide with Silk Fibroin
    MIN Si-Jia, CHEN Fang-Fang, WU Hao-Xiang
    2005, 26(5):  964-967. 
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    The structure of cross-linked fibroin gel(CFG) prepared by the reaction of cross-linking (agent) epoxide polyethylene glycol diglycidyl ether(PGDE) with silk fibroin solution was investigated. The results indicate that CFG express the whole homogeneous morphological structure observed by site microscopy phase contrast, while the pure fibroin gel(FG), which hadn't been cross-linked with PGDE, showed the particle-piled structure. There was an absorption peak of alkyl ether in PGDE appearing at 1 104 cm-1 of the FTIR spectrum of CFG, while it didn't show the characteristic peak of epoxide in both sides of PGDE. It revealed that PGDE has been cross-linked with silk fibroin by opening the rings. The amino acid analysis of CFG can be used to explain that the content of tyrosine, histidine and lysine obviously decreased after the reaction, and PGDE cross-linking occured at these sites. The chemical shift of C in tyrosine was observed in solid state 13C NMR spectra, so that it further proved the cross-linking PGDE with tyrosine residue. It is supposed that an intermolecular network structure can be formed by the cross-linking between PGDE and tyrosine, histidine and lysine residue of silk fibroin, which make CFG homogeneous and with better transparence and flexibility.
    Micro-structures and Mechanical Performance of Co-axial Nanofibers with Drug and Protein Cores and Polycaprolactone Shells
    HUANG Zheng-Ming, ZHANG Yan-Zhong
    2005, 26(5):  968-972. 
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    By a co-axial electrospinning technique, double-layered composite nanofibers with different core from shell materials can be fabricated. The composite nanofibers developed in this paper made use of some drug and a gelatin protein as cores and a biodegradable polymer, polycaprolactone, as shell. The micro-structures and mechanical performance of these nanofibers were characterized. It is shown that to encapsulate the drug in ultra-fine fibers whose wall thickness is less than 100 nm was achievable, even though the drug has a different dissolving solvent from that for the polymer shell material. Such kind of nanofibers can be used as sewing wires inside the human body or wound caring material for some heavy wounds such as burns. The tensile strengths of the nanofiber membranes decreased with the increase of the polymer concentrations in the core solutions.
    Effects of Substituents on the Third Order Nonlinear Optical Properties of Poly[(3-alkylthiophene-2,5-diyl)-(benzylidenequinomethene-2,5-diyl)] Derivatives
    GAO Chao, WU Hong-Cai, YI Wen-Hui, SUN Jian-Ping, MENG Ling-Jie
    2005, 26(5):  973-977. 
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    Five poly[(3-alkylthiophene) benzylidenequinomethene] derivatives: poly[(3-butylthiophene-2,5-diyl)-(p-nitrobenzylidenequinomethene-2,5-diyl)](PBTNBQ), poly[(3-hexylthiophene-2,5-diyl)-(p-nitrobenzylidenequinomethene-2,5-diyl)](PHTNBQ), poly[(3-hexylthiophene-2,5-diyl)-(p-N,N-dimethylamino)-benzylidenequinomethene-2,5-diyl](PBTDMABQ), poly[(3-hextylthiophene-2,5-diyl)-(p-N,N-dimethylamino)benzylidenequinomethene-2,5-diyl](PHTDMABQ) and poly[(3-octylthiophene-2,5-diyl)[(p-N,N-dimethylamino)benzylidenequinomethene-2,5-diyl](POTDMABQ) were synthesized. According to the function of band gap and energy of the incident photons, the band gaps of these polymers are calculated as 1.82, 1.85, 1.71, 1.78 and 1.67 eV, respectively. The homogenous films of these five polymers are prepared and their third-order nonlinear optical properties are studied with the backward degenerate four-wave mixing(DFWM) at 532 nm. By using the relative measurement technique, the third-order nonlinear optical susceptibilities of PBTNBQ, PHTNBQ, PBTDMABQ, PHTDMABQ and (POTDMABQ) films are measured as big as 1.74×10-8, 1.82×10-8, 5.62×10-9, 8.64×10-9 and (1.22×)10-8 esu respectively. It is found that the substitutents have a strong effects on nonlinear optical properties of poly[(3-alkylthiophene) benzylidenequinomethene] derivatives, the effects of substituents on the third order nonlinear properties of poly-[(3-alkylthiophene) benzylidenequinomethene] derivatives are illuminated with the delocalization degree of conjugated π electronics and the polarity of the polymers.
    Ring-opening Polymerization of Trimethylene Carbonate Catalyzed by PPL Immobilized on Silica Nanoparticles
    YU Xiang-Hua, ZHUO Ren-Xi, FENG Jun
    2005, 26(5):  978-981. 
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    The ring-opening polymerization of trimethylene carbonate(TMC) catalyzed by the immobilized porcine pancreas lipase on silica nanoparticles(IMPPL) was explored. The influences of IMPPL concentration and reaction temperature as well as reaction time on the molecular weight and yield of PTMC were studied. The ring-opening polymerization of TMC using the recycling IMPPL and the degradation of PTMC in the presence of IMPPL were also investigated. The experimental data showed that this IMPPL could not only catalyze the ring-opening polymerization of TMC at 60—100 ℃ efficiently, but also catalyze the degradation of PTMC at relatively high temperatures. The recycling IMPPL showed better catalytic activity and could be used repeatedly.
    Preparation of Electrophoretic Ink Microcapsules and Electrophoretic Display Prototype
    RONG Yu, WU Gang, CHEN Hong-Zheng, WANG Mang
    2005, 26(5):  982-984. 
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    TiO2 particles coated with polystyrene which were prepared via in situ polymerization and oil green dye were dispersed in tetrachloroethylene and xylene, the mixture came to be electrophoretic ink and was encapsulated in to microcapsules by complex coacervation from gelatin and a hydrolyzed copolymer of styrene and maleic anhydride(SMA). It was demonstrated that the membranes of the microcapsules were formed from nano sized coacervate droplets resulting from gelation and hydrolyzed SMA, which leads to a compact membrane structure. Microcapsules were characterized in terms of microstructure, morphologies by scanning electron microscopy(SEM). Electrophoretic display prototype was prepared by coating electrophoretic ink microcapsules slurry on ITO glass with nearly single layer and sealed by UV curable adhesives. The characters “Zheda” in Chinese was firstly displayed at a low volt 9 V D.C..
    Silica@Polymers Coaxial Nanofibers
    HONG You-Liang, SHANG Tie-Cun, JIN Yu-Wei, YANG Fan, WANG Ce
    2005, 26(5):  985-987. 
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    The preparation and formation mechanism of silica/polyvinylpyrrolidone(PVP)-polyacrylonitrile(PAN) coaxial nanofibers were presented in this paper. The PVP-PAN composite nanofibers were obtained via an electrospinning technique, while SiO2 nanoparticles were prepared according to a Stber method. The measurements of water contact angle(WCA), the compared results of silica coating PVP-PAN composite nanofibers with PAN nanofibers indicate that much PVP resided on the composite nanofiber surface, which results in the occurrence of SiO2@polymer coaxial nanofibers due to the formation of hydrogen bonding between silica and composite nanofibers and subsequent adsorption of silica on the fiber surface.
    Self-assembly Behavior of Polypeptide Graft Copolymer
    CHEN Tao, TANG Dong-Mei, LIN Jia-Ping, ZHU Guo-Quan, ZHANG Sun-Ning, TIAN Xiao-Hui
    2005, 26(5):  988-990. 
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    Polymeric micelles of poly(γ-benzyl L-glutamate)(PBLG)-poly(ethylene oxide)(PEO) graft copolymer were prepared by the dialysis method in deionized water. Fluorescence spectroscopy, nuclear magnetic resonance(NMR) and transmission electron microscope(TEM) were used for the investigation of the self-assembly of PBLG-PEO graft copolymer. Fluorescence spectrosco0y measurements suggest that PBLG-PEO graft copolymer associates to form polymeric micelles in water. 1H NMR measurements further prove that in aqueous medium PBLG-PEO graft copolymer could assemble into polymeric micelles with PBLG segments as the hydrophobic inner core and PEO segments as the hydrophilic shell. The results of the TEM observations show that the polymeric micelles of PBLG-PEO graft copolymer are almost spindly shaped, which are different from the morphology of the spherical micelles formed by PBLG-PEO block copolymer. Polymeric micelles formed by polypeptide copolymer have potential application as drug carrier in controlled-release delivery system.