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    24 December 2005, Volume 26 Issue 12
    Articles
    Synthesis and Characterization of [M(en)3][GeF6](M=Ni, Co) with H-bonded Pseudo-channel Structure
    PAN Qin-He, LI Ji-Yang, YU Ji-Hong, WANG Yu, FANG Qian-Rong, XU Ru-Ren
    2005, 26(12):  2199-2202. 
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    Two interesting H-bonded pseudo-channel structures [Ni(en)3][GeF6][JLG-1(Ni)] and [Co(en)3][GeF6][JLG-1(Co)] were describes  in this work . The [GeF6]2-anions interact with the chiral complex cations [M(en)3]2+ (M=Ni, Co) in such a way that pseudo-channels were formed along the 63 screw axis in a hexagonal, honeycomb array are created based on weak H-bonding of F…N atoms. It is believed that the chiral [M(en)3]2+ cations paired with [GeF6]2- anions in a D3 point symmetry is responsible for the fascinating arrangement in JLG-1(Ni) and JLG-1(Co). This work will be useful for the design of H-bonded pseudo-channel system.

    Synthesis and Characterization of [M(en)3][GeF6](M=Ni,Co) with H-bonded Pseudo-channel Structure
    PAN Qin-He, LI Ji-Yang, YU Ji-Hong, WANG Yu, FANG Qian-Rong, XU Ru-Ren
    2005, 26(12):  2199-2202,2190. 
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    Two interesting H-bonded pseudo-channel structures [Ni(en)3][GeF6][JLG-1(Ni)] and [Co(en)3][GeF6][JLG-1(Co)] were describes in this work.The [GeF6]2-anions interact with the chiral complex cations [M(en)3]2+(M=Ni,Co) in such a way that pseudo-channels were formed along the 63 screw axis in a hexagonal,honeycomb array are created based on weak H-bonding of F…N atoms.It is believed that the chiral([M(en)3]2+) cations paired with [GeF6]2- anions in a D3 point symmetry is responsible for the fascinating arrangement in JLG-1(Ni) and JLG-1(Co).This work will be useful for the design of H-bonded pseudo-channel system.
    Preparation of Ag/TiO2 Hybrid Nanoparticles in W/O Emulsion and Its Surface-enhanced Raman Scattering Effect
    ZHANG Dan, ZHANG Rong-Wei, SONG Xi-Meng, ZHAO Da-Cheng, ZHANG Meng, LI Ying, LIU Feng-Qi
    2005, 26(12):  2203-2206. 
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    Ag/TiO2 hybrid nanoparticles have been  synthesized via a remarkably simple one-pot route in water-in-oil emulsions, where the reduction of Ag+ to Ag0 in water phase and the hydrolysis of Ti(OC4H9)4 at the water/oil interface took place simultaneously. Such hybrid nanoparticles were characterized with  TEM, SPS, XPS and X-ray diffraction. The procedure led to form nanocomposites with Ag in the size range of 5-15 nm diameter enchased in amorphous TiO2 in the size range of 30-50 nm diameter in a typical synthesis. XRD results indicated that TiO2 upon thermal treatments, gets converted to crystalline oxides.  Both TiO2 and Ag/TiO2 nanoparticles prepared by our methods keep their anatase structures even above 700 ℃.Furthermore, SPS and XPS  measurements indicate that  Ag/TiO2 nanoparticles have special structure instead of the simple mixture of  Ag and TiO2 nanoparticles.  The surface-enhanced Raman scattering activity of the hybrid nanoparticles was also investigated, and the results revealed their potential application in SERS substrate materials.

    Preparation of Ag/TiO2 Hybrid Nanoparticles in W/O Emulsion and Its Surface-enhanced Raman Scattering Effect
    ZHANG Dan, ZHANG Rong-Wei, SONG Xi-Ming, ZHAO Da-Cheng, ZHANG Ming, LI Ying, LIU Feng-Qi
    2005, 26(12):  2203-2206,2190. 
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    Ag/TiO2 hybrid nanoparticles have been synthesized via a remarkably simple one-pot route in water-in-oil emulsions,where the reduction of Ag+ to Ag0 in water phase and the hydrolysis of Ti(OC4H9)4 at the water/oil interface took place simultaneously.Such hybrid nanoparticles were characterized with TEM,SPS,XPS and X-ray diffraction.The procedure led to form nanocomposites with Ag in the size range of 5-15 nm diameter enchased in amorphous TiO2 in the size range of 30-50 nm diameter in a typical synthesis.XRD results indicated that TiO2 upon thermal treatments,gets converted to crystalline oxides.Both TiO2 and(Ag/TiO2) nanoparticles prepared by our methods keep their anatase structures even above 700 ℃.Furthermore,SPS and XPS measurements indicate that Ag/TiO2 nanoparticles have special structure instead of the simple mixture of Ag and TiO2 nanoparticles. The surface-enhanced Raman scattering activity of the hybrid nanoparticles was also investigated,and the results revealed their potential application in SERS substrate materials.
    NTCR Effect of BaTiO3-based PTC Ceramics Penetrated by Rare Earth
    HAO Su-E, SUN Liang, HUANG Jin-Xiang, WEI Yong-De
    2005, 26(12):  2207-2210 . 
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    The modified BaTiO3-based PTC ceramics were prepared by gaseous penetration of rare earth La, and the change laws of the resistivity at room temperature and the temperature- resistivity properties were studied. The experimental results show that the modified BaTiO3 -based PTC ceramics after La penetration have a significant decrease in resistivity at room temperature, which decreases from 2.7×109 to 220 Ω·m,  and the resistivity decreases progressively from 220 to 5.8 Ω·m in the temperatures range from 25 ℃ to 500 ℃, which indicates a significant NTCR effect. Through analyses of XRD, SEM, EDAX and the dielectric properties of the BaTiO3-based PTC ceramics penetrated by La, the forming mechanism of the NTCR effect was explored, and the physical structure model of the NTCR effect was established.

    NTCR Effect of BaTiO3-based PTC Ceramics Penetrated by Rare Earth
    HAO Su-E, SUN Liang, HUANG Jin-Xiang, WEI Yong-De
    2005, 26(12):  2207-2210,2190. 
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    The modified BaTiO3-based PTC ceramics were prepared by gaseous penetration of rare earth La,and the change laws of the resistivity at room temperature and the temperature-resistivity properties were studied.The experimental results show that the modified BaTiO3-based PTC ceramics after La penetration have a significant decrease in resistivity at room temperature,which decreases from 2.7×109 to 220 Ω·m,and the resistivity decreases progressively from 220 to 5.8 Ω·m in the temperatures range from 25 ℃ to 500 ℃,which indicates a significant NTCR effect.Through analyses of XRD,SEM,EDAX and the dielectric properties of the BaTiO3-based PTC ceramics penetrated by La,the forming mechanism of the NTCR effect was explored,and the physical structure model of the NTCR effect was established.
    Letters
    Synthesis and Structure of a Novel Metal-organic Polymer Mn3(BTC)2(H2O)9·(H2O)
    XUE Ming,ZHU GS,WANG LF,FANG QR,SUN JY,SUN FX,GUO XD,ZHAO XJ,TIAN G,QIU SL
    2005, 26(12):  2211-2213 . 
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    A new metal-organic polymer Mn3(BTC)2(H2O)9·(H2O) was synthesized by reaction of the metal ions Mn(Ⅱ) with 1,3,5-benzenetricarboxylic acid(H3BTC) in a mixed solution of DMF/C2H5OH/H2O and crystallized. The crystal belongs to monoclinic system,space group C2/c with a=1.901 4(4) nm,b=0.740 23(15) nm,c=2.044 9(4) nm,β=97.18(3)°,V=2.855 5(10) nm3,Z=4,Dc=1.766 g/cm3,μ(Mo Kα)=1.401 mm-1,R[I>2σ(I)]=0.072 7,wR=0.235 1 for 2 419 independent reflections with goodness-of-fit 1.046. Its structure possesses bilayer architectures constructed from Mn ions linked infinite Mn(BTC) chains which were build up from BTC ligand as the “T-shape” module and Mn as the linear module.The hydrogen-bond and π-π stacking interactions between bilayers make them three-dimensional channel-like interpenetrated frameworks.

    Articles
    Synthesis and Structure of a Novel Metal-organic Polymer Mn3(BTC)2(H2O)9·(H2O)
    XUE Ming, ZHU Guang-Shan, WANG Li-Feng, FANG Qian-Rong, SUN Jin-Yu, SUN Fu-Xing, GUO Xiao-Dan, ZHAO Xiao-Jun, TIAN Ge, QIU Shi-Lun
    2005, 26(12):  2211-2213,2197. 
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    A new metal-organic polymer Mn3(BTC)2(H2O)9·(H2O) was synthesized by reaction of the metal ions Mn(Ⅱ) with 1,3,5-benzenetricarboxylic acid(H3BTC) in a mixed solution of DMF/C2H5OH/(H2O) and crystallized.The crystal belongs to monoclinic system,space group C2/c with a=1.901 4(4) nm,b=0.740 23(15) nm,c=2.0449(4) nm,β=97.18(3)°,V=2.855 5(10) nm3,Z=4,Dc=1.766(g/cm3),μ(Mo Kα)=1.401 mm-1,R[I>2σ(I)]=0.072 7,wR=0.235 1 for 2 419 independent reflections with goodness-of-fit 1.046. Its structure possesses bilayer architectures constructed from Mn ions linked infinite Mn(BTC) chains which were build up from BTC ligand as the "T-shape" module and Mn as the linear module.The hydrogen-bond and π-π stacking interactions between bilayers make them three-dimensional channel-like interpenetrated frameworks.
    Studies on Nano Ag2O2-PbO2 Modified Electrode-induced Cell Membranes and DNA Damage of E.coli
    GU Jing,ZHANG Wen,TANG Hui,JIN Li-Tong, ZUO Yi, WU Zi-Rong
    2005, 26(12):  2214-2217 . 
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    The fabrication of a novel nano Ag2O2-PbO2 modified electrode is described.Hydroxide radical could be generated on the surface of the  electrode at  an optimized potential.Lipid peroxidate and transudatory protein were detected to show destruction of cell membrane of E.coli treated by Ag2O2-PbO2 modified electrode.DNA damage of E.coli was  studied in detail with electrophoresis and DNA sequence determination.The results show that cracking of plasmid DNA and mutation of gene sequence could be induced by nano Ag2O2-PbO2 modified electrode.

    Studies on Nano Ag2O2-PbO2 Modified Electrode-induced Cell Membranes and DNA Damage of E.coli
    GU Jing, ZHANG Wen, TANG Hui, JIN Li-Tong, ZUO Yi, WU Zi-Rong
    2005, 26(12):  2214-2217,2190. 
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    The fabrication of a novel nano Ag2O2-PbO2 modified electrode is described.Hydroxide radical could be generated on the surface of the electrode at an optimized potential.Lipid peroxidate and transudatory protein were detected to show destruction of cell membrane of E.coli treated by Ag2O2-PbO2 modified electrode.DNA damage of E.coli was studied in detail with electrophoresis and DNA sequence determination.The results show that cracking of plasmid DNA and mutation of gene sequence could be induced by nano Ag2O2-PbO2 modified electrode.
    Multiresidue Determination of 17 Organochlorine and Pyrethroid Pesticides in Tea by Gas Chromatography-Negative Chemical Ionization-Mass Spectrometry
    LIN Zhu-Guang, JIN Zhen, LIU Yong, FAN Yu-Lan, TAN Jun, MA Yu, CHEN Mei-Yu, CHEN Zhao-Bin
    2005, 26(12):  2218-2222 . 
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    An analytical multiresidue method for the simultaneous determination of 17 pesticides(8 organochlorines and 9 pyrethroids) in tea was developed.Pesticides were extracted from tea with hexane-acetone(volume ratio is 1∶1) in an ultrasonic bath and cleaned up on a Florisil and neutral alumina column,then were determined by gas chromatography with negative chemical ionization mass spectrometric detection in the selected ion monitoring mode,and with heptachlor epoxide as the internal standard.Spiked blank samples were used as standards to counteract the matrix effect observed in the chromatographic determination. The recovery studies were performed at 20,50  and 200 μg/kg fortification levels for each pesticide,and the recoveries ranged from 67.9% to 129% with a relative standard deviation between 1.0% and 20% for the different pesticides.The detection limit of the method was less than 1.0 μg/kg for  most of pesticides except for the permethrin. The developed method was linear over the range assayed, 10-500 μg/L,with determination coefficients>0.996.Finally,the developed analytical method was  successfully applied to the determination of pesticides in several tea samples.

    Multiresidue Determination of 17 Organochlorine and Pyrethroid Pesticides in Tea by Gas Chromatography-Negative Chemical Ionization-Mass Spectrometry
    LIN Zhu-Guang, JIN Zhen, LIU Yong, FAN Yu-Lan, TAN Jun, MA Yu, CHEN Mei-Yu, CHEN Zhao-Bin
    2005, 26(12):  2218-2222,2190. 
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    An analytical multiresidue method for the simultaneous determination of 17 pesticides(8 organochlorines and 9 pyrethroids) in tea was developed.Pesticides were extracted from tea with hexane-acetone(volume ratio is 1∶1) in an ultrasonic bath and cleaned up on a Florisil and neutral alumina column, then were determined by gas chromatography with negative chemical ionization mass spectrometric detection in the selected ion monitoring mode,and with heptachlor epoxide as the internal standard.Spiked blank samples were used as standards to counteract the matrix effect observed in the chromatographic determination.The recovery studies were performed at 20,50 and 200 μg/kg fortification levels for each pesticide,and the recoveries ranged from 67.9% to 129% with a relative standard deviation between 1.0% and 20% for the different pesticides. The detection limit of the method was less than 1.0 μg/kg for most of pesticides except for the permethrin.The developed method was linear over the range assayed,10-500 μg/L,with determination coefficients>0.996.Finally,the developed analytical method was successfully applied to the determination of pesticides in several tea samples.
    Forming Law of Hydroxyl Radical During Electrolysis Process
    LIU Miao, DIAO Wei-Li, WU Di, JIAO Xin-Qian, LI Yan-Li, QUAN Fu-Min
    2005, 26(12):  2223-2226 . 
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    Hydroxyl radical is the main species of many free radical oxidation reactions. The strong oxidation ability of hydroxyl radical can be used to oxidize organic substances and other impurities in water, decreasing the Chemical Oxygen Demand (COD) value and reaching the goal of water treatment. Aromatic hydroxylation from the reaction between hydroxyl radical and salicylate or its related compounds has been often utilized as a marker for the generation of hydroxyl radicals. We have investigated several technical aspects of applying this method to study hydroxyl radical production during the electrolysis process  using the salicylic acid(2-HBA) to form 2,5-dihydroxybenzoic acid(2,5-DHBA). Aqueous solution of 2-HBA was electrolyzed by Ti-base lead dioxide electrode, then the solution containing 2-HBA and 2,5-DHBA was analyzed by High Performance Liquid Chromatography(HPLC) with fluorescence detection. The results show that high pH value is better than low pH value, also  high frequency is better than low frequency.

    Forming Law of Hydroxyl Radical During Electrolysis Process
    LIU Miao, DIAO Wei-Li, WU Di, JIAO Xin-Qian, LI Yan-Li, QUAN Fu-Min
    2005, 26(12):  2223-2226,2191. 
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    Hydroxyl radical is the main species of many free radical oxidation reactions.The strong oxidation ability of hydroxyl radical can be used to oxidize organic substances and other impurities in water,decreasing the Chemical Oxygen Demand(COD) value and reaching the goal of water treatment.Aromatic hydroxylation from the reaction between hydroxyl radical and salicylate or its related compounds has been often utilized as a marker for the generation of hydroxyl radicals.We have investigated several technical aspects of applying this method to study hydroxyl radical production during the electrolysis process using the salicylic acid(2-HBA) to form 2,5-dihydroxybenzoic acid(2,5-DHBA).Aqueous solution of 2-HBA was electrolyzed by Ti-base lead dioxide electrode,then the solution containing 2-HBA and 2,5-DHBA was analyzed by High Performance Liquid Chromatography(HPLC) with fluorescence detection.The results show that high pH value is better than low pH value,also high frequency is better than low frequency.
    Letter
    Detection of the Thyroid Tumor via Percutaneous,in vivo and in vitro Examination Using FT-mid-IR Fiber Optics Spectroscopy
    XU Yi-Zhuang, ZHAO Ying, XU Zhi, YANG Li-Min, LIU Yu-Feng, LING Xiao-Feng, ZHANG Neng-Wei, WANG Li-Xin, WANG Bing-Bing, MENG Tao, ZHANG Yuan-Fu, WENG Shi-Fu, ZHOU Xiao-Si, XU Duan-Fu, WU Jin-Guang
    2005, 26(12):  2227-2229 . 
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    In the present paper,FT-mid-IR fiber optics spectroscopy was used to determine the thyroid    tumor. A modified WQF-500 FTIR spectrometer with MCT detector and mid-IR fiber optics ATR accessory was used in this work. Percutaneous examination of the skin overlying the thyroid tumor was performed on five patients,in vivo detection and in vitro measurement of six patients in operation room was also carried out. The experimental data indicate that malignant and benign thyroid tumor could be distinguished from the spectra of percutaneous examination,the in vivo measurement and freshly resected thyroid tissues. The relative intensity and peak position of the IR bands in the region of 1 700-1 500 cm-1(amide Ⅰ and amide Ⅱ),1 480-1 400 cm-1,and 1 320-1 200 cm-1 are reliable spectral marker or indexes for tumor detection. These results demonstrate that FT-mid-IR fiber optics spectroscopy exhibits prospect to develop a novel non-invasive method for thyroid tumor detection.

    Articles
    Detection of the Thyroid Tumor via Percutaneous,in vivo and in vitro Examination Using FT-mid-IR Fiber Optics Spectroscopy
    XU Yi-Zhuang, ZHAO Ying, XU Zhi, YANG Li-Min, LIU Yu-Feng, LING Xiao-Feng, ZHANG Neng-Wei, WANG Li-Xin, WANG Bing-Bing, MENG Tao, ZHANG Yuan-Fu, WENG Shi-Fu, ZHOU Xiao-Si, XU Duan-Fu, WU Jin-Guang
    2005, 26(12):  2227-2229,2196. 
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    In the present paper,FT-mid-IR fiber optics spectroscopy was used to determine the thyroid tumor.A modified WQF-500 FTIR spectrometer with MCT detector and mid-IR fiber optics ATR accessory was used in this work.Percutaneous examination of the skin overlying the thyroid tumor was performed on five patients,in vivo detection and in vitro measurement of six patients in operation room was also carried out.The experimental data indicate that malignant and benign thyroid tumor could be distinguished from the spectra of percutaneous examination,the in vivo measurement and freshly resected thyroid tissues.The relative intensity and peak position of the IR bands in the region of 1 700-1 500 cm-1(amide Ⅰ and amide Ⅱ),1 480-1 400 cm-1,and 1 320-1 200 cm-1 are reliable spectral marker or indexes for tumor detection.These results demonstrate that FT-mid-IR fiber optics spectroscopy exhibits prospect to develop a novel non-invasive method for thyroid tumor detection.
    Letters
    Studies on Metabolites of Pilocarpine in Human Urine Using High-performance Liquid Chromatography with Tandem Mass Spectrometry
    WANG Ling,WANG Ying-Wu,CHEN Gang,YUAN Hong-Ming
    2005, 26(12):  2230-2232. 
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    Metabolism of pilocarpine in human urine was studied by high-performance liquid chromatography with tandem mass spectrometric method after single oral dose 10 mg pilocarpine hydrochloride to a healthy male volunteer.The urine sample was collected from 0 to 8 h after oral administration.The urine sample was prepared by solid phase extraction,and then was analyzed  using high-performance liquid chromatography coupled with a triple quadrupole tandem mass spectrometer in multiple reaction monitoring and product ion scan mode.Three metabolites were identified as the oxidative metabolite,pilocarpic acid and the glucuronide of pilocarpine.

    Articles
    Studies on Metabolites of Pilocarpine in Human Urine Using High-performance Liquid Chromatography with Tandem Mass Spectrometry
    WANG Ling, WANG Ying-Wu, CHEN Gang, YUAN Hong-Ming
    2005, 26(12):  2230-2232,2191. 
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    Metabolism of pilocarpine in human urine was studied by high-performance liquid chromatography with tandem mass spectrometric method after single oral dose 10 mg pilocarpine hydrochloride to a healthy male volunteer.The urine sample was collected from 0 to 8 h after oral administration. The urine sample was prepared by solid phase extraction,and then was analyzed using high-performance liquid chromatography coupled with a triple quadrupole tandem mass spectrometer in multiple reaction monitoring and product ion scan mode. Three metabolites were identified as the oxidative metabolite,pilocarpic acid and the glucuronide of pilocarpine.
    Antibacterial and Hemolytic Activities of the Reverse-sequence Analogs of a Melittin′s C-terminal Segment
    CHEN Su-Xia, SUN Xue-Jun, LI Shun-Zi, YAN Hu-Sheng
    2005, 26(12):  2233-2236. 
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    Melittin is an amphipathic α-helical peptide with 26 amino acids. It has   high antimicrobial activity and  toxicity to  eukaryotic cells. C-terminal 15-residue fragment of melittin(GLPALISWIKRKRQQ-NH2), M(12-26), retained some of the antimicrobial activity but lost most of the hemolytic activitiy. A series of reverse-sequence analogs of M(12-26) with various numbers of basic amino acid residues and various lengths of the hydrophobic segment  were synthesized. In the reverse-sequence analogs, the positive charges introduced by the basic residues and the N-terminal amino group were gathered in the N-terminus, while the hydrophobic segment was located in the C-terminus. The results indicate both of the positive charge and the hydrophobicity of the reverse-sequence analogs were necessary for the antimicrobial and hemolytic activities. At least three N-terminal basic animo acids and eight amino acid residues for the hydrophobic segment were required for high antimicrobial activity. A 11-residue peptide, RetroMel(13-23) was the shortest peptide  retaining the antimicrobial activity. All these of the reverse-sequence analogs possessed very low hemolysis.

    Antibacterial and Hemolytic Activities of the Reverse-sequence Analogs of a Melittin's C-terminal Segment
    CHEN Su-Xia, SUN Xue-Jun, LI Shun-Zi, YAN Hu-Sheng
    2005, 26(12):  2233-2236,2191. 
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    Melittin is an amphipathic α-helical peptide with 26 amino acids.It has high antimicrobial activity and toxicity to eukaryotic cells.C-terminal 15-residue fragment of melittin(GLPALISWIKRKRQQ-NH2),(M(12-26)),retained some of the antimicrobial activity but lost most of the hemolytic activitiy.A series of reverse-sequence analogs of M(12-26) with various numbers of basic amino acid residues and various lengths of the hydrophobic segment were synthesized.In the reverse-sequence analogs,the positive charges introduced by the basic residues and the N-terminal amino group were gathered in the N-terminus,while the hydrophobic segment was located in the C-terminus.The results indicate both of the positive charge and the hydrophobicity of the reverse-sequence analogs were necessary for the antimicrobial and hemolytic activities.At least three N-terminal basic animo acids and eight amino acid residues for the hydrophobic segment were required for high antimicrobial activity.A 11-residue peptide,RetroMel(13-23) was the shortest peptide retaining the antimicrobial activity.All these of the reverse-sequence analogs possessed very low hemolysis.
    Application of 2-(1,3-Dithian-2-ylidene)-3-oxobutanoic Acid as 1,3-Propanedithiol Equivalent in Thioacetalization Reactions
    OU Yang-Yan, YU Hai-Feng, DONG De-Wen, LIU Jun, WANG Mang, LIU Qun
    2005, 26(12):  2237-2240. 
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    The thioacetalization of carbonyl compounds 2 by using 2-(1,3-dithian-2-ylidene)-3-oxobutanoic acid as 1,3-propanedithiol equivalent and ethanol as solvent was investigated. The results showed that the thioacetalization of various carbonyl compounds proceeded smoothly and rapidly and afforded the corresponding dithioacetals 3 in high yields. Moreover, the thioacetalization exhibited a high chemoselectivity between aldehyde and ketone.

    Application of 2-(1,3-Dithian-2-ylidene)-3-oxobutanoic Acid as 1,3-Propanedithiol Equivalent in Thioacetalization Reactions
    OUYANG Yan, YU Hai-Feng, DONG De-Wen, LIU Jun, WANG Mang, LIU Qun
    2005, 26(12):  2237-2240,2191. 
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    The thioacetalization of carbonyl compounds 2 by using 2-(1,3-dithian-2-ylidene)-3-oxobutanoic acid as 1,3-propanedithiol equivalent and ethanol as solvent was investigated.The results showed that the thioacetalization of various carbonyl compounds proceeded smoothly and rapidly and afforded the corresponding dithioacetals 3 in high yields.Moreover,the thioacetalization exhibited a high chemoselectivity between aldehyde and ketone.
    Synthesis, Structure and Bioactivity of Nitrobenzoimidazole Derivatives
    WANG Lu-Yao, GAO Yong, YANG Bing-Qin, SHI Zhen
    2005, 26(12):  2241-2246. 
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    It was reported that benzoimidazole and ferrocene compounds maybe exhibit high pharmaceutical functions. Eight new nitrobenzoimidazole derivatives were prepared by the reaction of ferrocene sulfonylchloride with 5-nitrobenzoimidazole and characterized by means of elemental analysis, MS and 1H NMR. The structure of the new compounds was further confirmed by X-ray crystallograghic analysis as exemplified by compounds 3b. The activities of compounds 3a-4d were evaluated against five fungicides. Compared with carbendazim(50% wet powder), better inhibitory activities were observed for these synthesized compounds.

    Synthesis,Structure and Bioactivity of Nitrobenzoimidazole Derivatives
    WANG Lu-Yao, GAO Yong, YANG Bing-Qin, SHI Zhen
    2005, 26(12):  2241-2246,2191. 
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    It was reported that benzoimidazole and ferrocene compounds maybe exhibit high pharmaceutical functions.Eight new nitrobenzoimidazole derivatives were prepared by the reaction of ferrocene sulfonylchloride with 5-nitrobenzoimidazole and characterized by means of elemental analysis,MS and 11H NMR.The structure of the new compounds was further confirmed by X-ray crystallograghic analysis as exemplified by compounds 3b.The activities of compounds 3a-4d were evaluated against five fungicides.Compared with carbendazim(50% wet powder),better inhibitory activities were observed for these synthesized compounds.
    Syntheses,Crystal Structures and Biological Activity of Bimethylation Daidzein Sulfonates
    ZHANG Zun-Ting, WANG Qiu-Ya, HE Yun, WANG Xiao-Bing, XUE Dong, ZHENG Jian-Bin
    2005, 26(12):  2247-2253. 
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    The water soluble derivatives of daidzein sodium 7,4′-bimethoxylisoflavone-3′-sulfonate(1) and copper(Ⅱ) 7,4′-bimethoxylisoflavone-3′-sulfonate(2)  were synthesized and their structures were characterized by IR,  NMR,  ESI-MS and X-ray diffraction analyses.  In the crystal structure of compound 1,  each sodium ion is six-coordinated by oxygens from the methoxyl and suflo-group of 7,4′-bimethoxylisoflavone-3′-sulfonate and H2O.  Two adjacent sodium ions were bridged by the oxygen atoms from suflo-group and a six-membered ring is formed.  The six-membered ring consists of two sodium ions,  three oxygen atoms from two suflo-groups and a sulfur atom.  The Na—O bonds of adjacent rings are paralleled with each other and form an one-dimensional zigzag sodium polyion chain along  axis c of the unit cell.  The sodium ions chains are also connected by the hydrogen bonds among coordination water molecules,  between coordination water molecules and oxygen from suflo-group.  The coordination interaction,  hydrogen bonds and the electrostatic interaction between sodium ion and —SO-3 made compound 1 assemble supramolecular ion polymer with two-dimensional structure.  The crystal of compound 2 consists of [Cu(H2O)6]2+,  C17H13O4SO-3 and H2O.  Cu(Ⅱ) is at the symmetry center of structure of compound 2 and octahedrally coordinated by six water molecule. [Cu(H2O)6]2+,  C17H13O4SO-3 and H2O form several kinds of hydrogen bonds.  The distance of 0.358 2 nm between anti-parallel isoflavone rings shows a π…π stacking interaction.  The hydrogen bonds and π…π stacking interaction lead to supramolecular formation with three-dimensional network structure.  The biological activities of resistance to hypoxia and anoxemia were tested,  the results show that the biological activities of resistance to hypoxia and anoxemia of compounds 1 and 2 were better than that of daidzein.

    Syntheses,Crystal Structures and Biological Activity of Bimethylation Daidzein Sulfonates
    ZHANG Zun-Ting, WANG Qiu-Ya, HE Yun, WANG Xiao-Bing, XUE Dong, ZHENG Jian-Bin
    2005, 26(12):  2247-2253,2191. 
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    The water soluble derivatives of daidzein sodium 7,4'-bimethoxylisoflavone-3'-sulfonate(1) and copper(Ⅱ) 7,4'-bimethoxylisoflavone-3'-sulfonate(2) were synthesized and their structures were characterized by IR,NMR,ESI-MS and X-ray diffraction analyses.In the crystal structure of compound 1,each sodium ion is six-coordinated by oxygens from the methoxyl and suflo-group of 7,4'-bimethoxylisoflavone-3'-sulfonate and H2O.Two adjacent sodium ions were bridged by the oxygen atoms from suflo-group and a six-membered ring is formed.The six-membered ring consists of two sodium ions,three oxygen atoms from two suflo-groups and a sulfur atom.The Na—O bonds of adjacent rings are paralleled with each other and form an one-dimensional zigzag sodium polyion chain along axis c of the unit cell. The sodium ions chains are also connected by the hydrogen bonds among coordination water molecules,between coordination water molecules and oxygen from suflo-group.The coordination interaction,hydrogen bonds and the electrostatic interaction between sodium ion and —SO-3 made compound 1 assemble supramolecular ion polymer with two-dimensional structure.The crystal of compound 2 consists of [Cu(H2O)6]2+,C17H13O4SO-3 and H2O.Cu(Ⅱ) is at the symmetry center of structure of compound 2 and octahedrally coordinated by six water molecule.[Cu(H2O)6]2+,C17H13O4SO-3 and H2O form several kinds of hydrogen bonds.The distance of 0.358 2 nm between anti-parallel isoflavone rings shows a π…π stacking interaction. The hydrogen bonds and π…π stacking interaction lead to supramolecular formation with three-dimensional network structure.The biological activities of resistance to hypoxia and anoxemia were tested,the results show that the biological activities of resistance to hypoxia and anoxemia of compounds 1 and 2 were better than that of daidzein.
    Synthesis and Anti-inflammatory Activities of Diaryl-substituted-1,2,4-trizole Derivatives
    XU Jin-Yi, YAO He-Quan, ZENG Yi, HUA Wei-Yi, WU Xiao-Ming, WANG Qiu-Juan, HU Song, WU Xue-Feng, YUE Pan
    2005, 26(12):  2254-2258 . 
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    Nonsteroidal anti-inflammatory durgs(NSAIDs) are among the most widely prescribed medications with their uses limited by significant toxicity.  The studies of the cyclooxygenase(COX)  show that the side effects of classical NSAIDs come from the inhibition of COX-1, while the therapeutic effects come from the inhibition of COX-2.  Selective COX-2 inhibitors were developed as NSAIDs which display the profiles of good potent activities and low side effects.  In order to search for the new NSAIDs, using the marketed selective COX-2 inhibitor celecoxib as a leading compound and based on the result of molecular modeling study of  COX-2 inhibitors, a series of novel diaryl-substituted-1,2,4-trizole derivatives were designed and synthesized.  All the target compounds were confirmed by IR, MS, 1H NMR spectra and elemental analysis.  The results of preliminary pharmacological tests in vivo show that some compounds have certain anti-inflammatory effect.

    Synthesis and Anti-inflammatory Activities of Diaryl-substituted-1,2,4-trizole Derivatives
    XU Jin-Yi, YAO He-Quan, ZENG Yi, HUA Wei-Yi, WU Xiao-Ming, WANG Qiu-Juan, HU Song, WU Xue-Feng, YUE Pan
    2005, 26(12):  2254-2258,2191. 
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    Nonsteroidal anti-inflammatory durgs(NSAIDs) are among the most widely prescribed medications with their uses limited by significant toxicity.The studies of the cyclooxygenase(COX) show that the side effects of classical NSAIDs come from the inhibition of COX-1,while the therapeutic effects come from the inhibition of COX-2.Selective COX-2 inhibitors were developed as NSAIDs which display the profiles of good potent activities and low side effects. In order to search for the new NSAIDs,using the marketed selective COX-2 inhibitor celecoxib as a leading compound and based on the result of molecular modeling study of COX-2 inhibitors,a series of novel diaryl-substituted-1,2,4-trizole derivatives were designed and synthesized.All the target compounds were confirmed by IR,MS,1H NMR spectra and elemental analysis.The results of preliminary pharmacological tests in vivo show that some compounds have certain anti-inflammatory effect.
    Purification and Analysis of Antigencity of Chimeric Antigen of HIV-1
    JIANG Jing, ZHAO Li-Hui, YU Xiang-Hui, JIANG Chun-Lai, WU Yong-Ge, MAO Pen-Yong, LI Wei, KONG Wei
    2005, 26(12):  2259-2263. 
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    In order to get the high-efficient diagnosing reagent of HIV, we choose three segments of HIV-1 envelope protein as the immune antigen, 469-511aa, 538-674aa and 700-734aa, which include more epitope. These three segment genes were obtained by PCR amplification and cloned into prokaryotic expressing vector. The results show that chimeric env protein can be expressed in E. coli BL21 strain high efficiently. We purified the protein by metal Ni-sepharose 4B, the data of ELISA demonstrate that purified chimeric antigen has good antigenic specificity.

    Purification and Analysis of Antigencity of Chimeric Antigen of HIV-1
    JIANG Jing, ZHAO Li-Hui, YU Xiang-Hui, JIANG Chun-Lai, WU Yong-Ge, MAO Pan-Yong, LI Wei, KONG Wei
    2005, 26(12):  2259-2263,2191. 
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    In order to get the high-efficient diagnosing reagent of HIV,we choose three segments of HIV-1 envelope protein as the immune antigen,469-511aa,538-674aa and 700-734aa,which include more epitope.These three segment genes were obtained by PCR amplification and cloned into prokaryotic expressing vector.The results show that chimeric env protein can be expressed in E.coli BL21 strain high efficiently.We purified the protein by metal Ni-sepharose 4B,the data of ELISA demonstrate that purified chimeric antigen has good antigenic specificity.
    Letter
    Baeyer-Villiger Reaction of (+)-Chrysanthenone
    SONG Zhi-Guang, LI Jing, LIU Qiang-Wen, LI Ye-Zhi, HUANG Hua-Min
    2005, 26(12):  2264-2266. 
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    The Baeyer-Villiger reaction is an oxidative transformation of katones into esters by peracid,which is an important method for functional group transformation as well as for ring expansion in organic synthesis.Oxidation of cyclic ketones into lactones has been employed for heterocycles and functionalized carbon chains.The reaction is reliable for controlling the regioselectivity and stereochemistry of the products,it is widely used as a key ring expansion step for the synthesis of natural products,including antibiotics steroids and pheromones.Particularly many complex structure of oxyacids would be synthesized by lactones via hydrolysis.In this paper we reported that (+)-chrysanthenone(2)([α]20D=+38.0) was obtained from crude(+)-verbenone without purification on the irradiation with ultraviolet light in Quartz flask.When (+)-chrysanthenone underwent Baeyer-Villiger oxidation by using oxidant H2O2 and CH3COOH as the oxidant the lactone 2,8,8-trimethyl-6-oxo-7-oxabicyclo[3.2.1]oct-2-ene(3)([α]20D=+65.0) was formed.Then compound  3 was  hydrolysized to afford 2,2,4-trimethyl-5-hydroxycyclohexen-3-yl carboxylic acid(4)([α]20D=+50.0).Compound 4 was oxidized by pyridinium chlorochromate to afford conjugated ketone acid 2,2,4-trimethy-3-oxocyclohexen-4-yl carboxylic acid 5. The structure of compounds 2,3,4,5 were identified by 1H NMR,IR and chemical reaction.The mechanism of oxidation of lactone 3 in the Baeyer-Villiger reaction was discussed.In this reaction the migrating group is a  secondary carbon group holding allyl function.

    Articles
    Baeyer-Villiger Reaction of(+)-Chrysanthenone
    SONG Zhi-Guang, LI Jing, LIU Qing-Wen, LI Ye-Zhi, HUANG Hua-Min
    2005, 26(12):  2264-2266,2196. 
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    The Baeyer-Villiger reaction is an oxidative transformation of katones into esters by peracid,which is an important method for functional group transformation as well as for ring expansion in organic synthesis.Oxidation of cyclic ketones into lactones has been employed for heterocycles and functionalized carbon chains.The reaction is reliable for controlling the regioselectivity and stereochemistry of the products,it is widely used as a key ring expansion step for the synthesis of natural products,including antibiotics steroids and pheromones.Particularly many complex structure of oxyacids would be synthesized by lactones via hydrolysis.In this paper we reported that(+)-chrysanthenone(2)(\20<sub>D=+38.0) was obtained from crude(+)-verbenone without purification on the irradiation with ultraviolet light in Quartz flask.When(+)-chrysanthenone underwent Baeyer-Villiger oxidation by using oxidant H2O2and CH3COOH as the oxidant the lactone 2,8,8-trimethyl-6-oxo-7-oxabicyclo[3.2.1]oct-2-ene(3)(\20<sub>D=+65.0) was formed.Then compound 3 was hydrolysized to afford 2,2,4-trimethyl-5-hydroxycyclohexen-3-yl carboxylic acid(4)(\20<sub>D=+50.0).Compound 4 was oxidized by pyridinium chlorochromate to afford conjugated ketone acid 2,2,4-trimethy-3-oxocyclohexen-4-yl carboxylic acid 5.The structure of compounds 2,3,4,5 were identified by()1H NMR,IR and chemical reaction.The mechanism of oxidation of lactone 3 in the Baeyer-Villiger reaction was discussed.In this reaction the migrating group is a secondary carbon group holding allyl function.
    Letters
    Synthesis of Polyamides Containing N-Methylpyrrole Rings and Their Interaction with DNA
    LI Qin-Ling,ZHOU Jiang,LIU Dan,YUAN Gu
    2005, 26(12):  2267-2269 . 
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    Polyamides containing N-methylpyrrole and N-methylimidazole amino acids have attracted considerable attention from biological chemists because they can permeate living cell membrane and have the potential to control specific gene expression.In this article,three polyamides containing N-methylpyrrole rings were synthesized by the chloroform reaction and the DCC/HOBT coupling reaction,and the interaction between the polyamides and DNA was investigated by electrospray ionization mass spectroscopy.The results of the experiments indicate that the designed polyamides can effectively bind the target DNA,and ESI mass spectrometry is an excellent tool for the analysis of the interactions between DNA and the polyamides.

    Articles
    Synthesis of Polyamides Containing N-Methylpyrrole Rings and Their Interaction with DNA
    LI Qin-Ling, ZHOU Jiang, LIU Dan, YUAN Gu
    2005, 26(12):  2267-2269,2198. 
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    Polyamides containing N-methylpyrrole and N-methylimidazole amino acids have attracted considerable attention from biological chemists because they can permeate living cell membrane and have the potential to control specific gene expression.In this article,three polyamides containing N-methylpyrrole rings were synthesized by the chloroform reaction and the DCC/HOBT coupling reaction,and the interaction between the polyamides and DNA was investigated by electrospray ionization mass spectroscopy.The results of the experiments indicate that the designed polyamides can effectively bind the target DNA,and ESI mass spectrometry is an excellent tool for the analysis of the interactions between DNA and the polyamides.
    Letters
    Triterpenoids from the Sponge Stelletta sp.Collected from the South China Sea
    LAN Wen-Jian,LIN Cui-Wu,SU Jing-Yu,ZENG Long-Mei
    2005, 26(12):  2270-2272 . 
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    Three isomalabaricane and malabaricane triterpenoids(1-3) were isolated from the sponge Stelletta sp.collected from Weizhou Island,Guangxi Province.The structures of compounds 1-3 were identified mainly by spectroscopic methods and X-ray diffraction analysis.All 1H NMR and 13C NMR signals of compound 1 were assigned for the first time on the basis of HMQC,1H-1H COSY and HMBC experiment.Antitumor assay exhibits that compounds 1,2 and 3 have a significant antitumor activity against P388 tumor cell lines with ED50 values 0.01,0.5,1.0 μg/mL,respectively.

    Articles
    Triterpenoids from the Sponge Stelletta sp.Collected from the South China Sea
    LAN Wen-Jian, LIN Cui-Wu, SU Jing-Yu, ZENG Long-Mei
    2005, 26(12):  2270-2272,2198. 
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    Three isomalabaricane and malabaricane triterpenoids(1-3) were isolated from the sponge Stelletta sp.collected from Weizhou Island,Guangxi Province.The structures of compounds 1-3 were identified mainly by spectroscopic methods and X-ray diffraction analysis.All 1H NMR and 13C NMR signals of compound 1 were assigned for the first time on the basis of HMQC,<sup>1H-<sup>1H COSY and HMBC experiment.Antitumor assay exhibits that compounds 1,2 and 3 have a significant antitumor activity against P388 tumor cell lines with ED50 values 0.01,0.5,1.0 μg/mL,respectively.
    Fenton Photocatalytic Degradation of Organic Dye Under Visible Irradiation
    HUANG Ying-Ping, LIU De-Fu, ZHANG Shui-Ying, ZHANG De-Li, MA Wan-Hong, ZHAO Jin-Cai
    2005, 26(12):  2273-2278 . 
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    A photooxidative system for degradation of organic dye pollutant RhB as an objective compound was reported under visible irradiation(λ>450 nm) by using Fe3+/H2O2as the Fenton reagent. It was found that, in the system with pH<3.0, visible light irradiation significantly accelerates the degradation process by photosensitive effect. After 160 min the RhB was mineralized with a yield of 71.8%. Bromocresol green reaction spectrophotometrically, spin-trapping electron paramagnetic resonance, UV-Vis spectroscopy, IR and total organic carbon(TOC) measurements were used to detect the photoreaction process. The photocatalytic degradation pathway mainly involves the formation of ·OH and carboxylie acids are the main intermediate products. H2O2 of Fe3+/H2O2/RhB system was utilized lowlier than that of supermolecular metal/organie complexes or supported catalysts system.

    Fenton Photocatalytic Degradation of Organic Dye Under Visible Irradiation
    HUANG Ying-Ping, LIU De-Fu, ZHANG Shui-Ying, ZHANG De-Li, MA Wan-Hong, ZHAO Jin-Cai
    2005, 26(12):  2273-2278,2192. 
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    A photooxidative system for degradation of organic dye pollutant RhB as an objective compound was reported under visible irradiation(λ>450 nm) by using Fe3+/H2O2 as the Fenton reagent. It was found that,in the system with pH<3.0,visible light irradiation significantly accelerates the degradation process by photosensitive effect.After 160 min the RhB was mineralized with a yield of 71.8%.Bromocresol green reaction spectrophotometrically,spin-trapping electron paramagnetic resonance,UV-Vis spectroscopy,IR and total organic carbon(TOC) measurements were used to detect the photoreaction process.The photocatalytic degradation pathway mainly involves the formation of &#183;OH and carboxylie acids are the main intermediate products. H2O2 of Fe3+/H2O2/RhB system was utilized lowlier than that of supermolecular metal/organie complexes or supported catalysts system.
    Preparation, Structure of Doped Ferrite and Its Performance of Decomposition of Carbon Dioxide to Carbon
    FU Mao-Sheng, CHEN Lin-Shen, CHEN Song-Ying
    2005, 26(12):  2279-2283. 
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    The structure of the doped ferrite prepared by mixing ions co-precipitation was characterized by XRD, TGA and H2-TPR, and the catalytic performance of CO2decomposition to C with its hydrogen-reduced Cr3+doped ferrite was evaluated. The results show that NiFe2O4 doped  Cr3+ has a single spinel structure and nano-size crystal. The results also indicate that the introduction of  Cr3+ into B site of the spinel structure of NiFe2O4could enhance its structure stability remarkably during the process of reaction cycles of H2 reduction and CO2 decomposition, as well as did decrease greatly the collapse rate of its structure, resulting in prolonging the reaction cycle life(over 35 cycles) and increasing carbon deposit(about 25.3%).

    Preparation,Structure of Doped Ferrite and Its Performance of Decomposition of Carbon Dioxide to Carbon
    FU Mao-Sheng, CHEN Lin-Shen, CHEN Song-Ying
    2005, 26(12):  2279-2283,2192. 
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    The structure of the doped ferrite prepared by mixing ions co-precipitation was characterized by XRD,TGA and H2-TPR,and the catalytic performance of CO2 decomposition to C with its hydrogen-reduced Cr3+ doped ferrite was evaluated.The results show that NiFe2O4 doped Cr3+ has a single spinel structure and nano-size crystal.The results also indicate that the introduction of Cr3+ into B site of the spinel structure of NiFe2O4 could enhance its structure stability remarkably during the process of reaction cycles of H2 reduction and CO2decomposition,as well as did decrease greatly the collapse rate of its structure,resulting in prolonging the reaction cycle life(over 35 cycles) and increasing carbon deposit(about 25.3%).
    Catalytic Kinetics of Nitrile Hydratase Measured in Real-time by Ultraviolet Spectrometry
    LIU Ming, GAO Yi, CAO Zhu-An
    2005, 26(12):  2284-2288. 
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    Nitrile hydratase(NHase), which catalyzes the hydration of nitriles to amides, is applied to industrial production of acrylamide. Kinetics of acrylonitrile hydration catalyzed by NHase is essential for the investigation of enzymatic properties and industrial production of acrylamide. The key in the study of enzymatic kinetics is to determine the real-time amount of acrylamide formed in the hydration, and then to calculate the initial reaction rate. A novel analytical method was developed to monitor the kinetics of acrylonitrile hydration catalyzed by purified Nocardia sp. NHase. The amount of acrylamide formed in the process was measured on-line by ultraviolet spectrometry with 275 nm wavelength. Compared with the conventional method of gas chromatography, UV spectroscopy is more sensitive and rapid for analyzing acrylamide quantitatively in real-time. The reaction rates in a series of initial concentrations of acrylonitrile were measured and calculated from the time-varying ultraviolet absorption. The kinetic correlation between reaction rate and acrylonitrile concentration was fitted with Michaelis-Menten equation. Michaelis constant(Km) and catalytic constant(kcat) were calculated to be 8.46 mmol/L and 2398 μmol/(min·mg), respectively.

    Catalytic Kinetics of Nitrile Hydratase Measured in Real-time by Ultraviolet Spectrometry
    LIU Ming, GAO Yi, CAO Zhu-An
    2005, 26(12):  2284-2288,2192. 
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    Nitrile hydratase(NHase),which catalyzes the hydration of nitriles to amides,is applied to industrial production of acrylamide.Kinetics of acrylonitrile hydration catalyzed by NHase is essential for the investigation of enzymatic properties and industrial production of acrylamide.The key in the study of enzymatic kinetics is to determine the real-time amount of acrylamide formed in the hydration,and then to calculate the initial reaction rate.A novel analytical method was developed to monitor the kinetics of acrylonitrile hydration catalyzed by purified Nocardia sp.NHase.The amount of acrylamide formed in the process was measured(on-line) by ultraviolet spectrometry with 275 nm wavelength.Compared with the conventional method of gas chromatography,UV spectroscopy is more sensitive and rapid for analyzing acrylamide quantitatively in real-time.The reaction rates in a series of initial concentrations of acrylonitrile were measured and calculated from the time-varying ultraviolet Absorption.The kinetic correlation between reaction rate and acrylonitrile concentration was fitted with Michaelis-Menten equation.Michaelis constant(K_m) and catalytic constant(k\cat) were calculated to be 8.46 mmol/L and 2398 μmol/(min·mg),respectively.
    Theoretical Studies on the Charge and Discharge Processes of Graphite Cathode with DFT Method
    HUANG Zong-Hao, KAN Yu-He, XU Dong, MA Shu-Rong, YANG Gui-Xia, MENG Su-Ci, SU Zhong-Min
    2005, 26(12):  2289-2292. 
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    The intercalation and absorption processes of Li in graphite cathode of Li-secondary battery were discussed by DFT-B3LYP/6-31G(d) method of quantum chemistry. The storage energy curves of the intercalation processes through the routes of arm-chair and zig-zag directions and the adsorption processes of Li on the graphite surface along three typical directions were calculated. The results show that (1) the intercalation process of Li is a process of energy storage; when Li is just located on the projecting position of carbon atom, the system energy is the highest; when Li is located on the projecting position of carbon-carbon bond, the system energy is higher, and when the Li located on the projecting position of benzene ring center, the system possesses the lowest energy and is the most stable. The arm-chair direction is the most probable route for intercalating of Li to graphite cathode; (2) the process of adsorption of Li on the graphite cathode surface is a process of energy storage, too; the position over the center of benzene ring is the most probable adsorption position when Li is close to the graphite surface. The present article provides a very useful image for understanding and improving the charge and discharge properties of the graphite cathode.

    Theoretical Studies on the Charge and Discharge Processes of Graphite Cathode with DFT Method
    HUANG Zong-Hao, KAN Yu-He, XU Dong, MA Shu-Rong, YANG Gui-Xia, MENG Su-Ci, SU Zhong-Min
    2005, 26(12):  2289-2292,2192. 
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    The intercalation and Absorption processes of Li in graphite cathode of Li-secondary battery were discussed by DFT-B3LYP/6-31G(d) method of quantum chemistry.The storage energy curves of the intercalation processes through the routes of arm-chair and zig-zag directions and the adsorption processes of Li on the graphite surface along three typical directions were calculated.The results show that(1) the intercalation process of Li is a process of energy storage;when Li is just located on the projecting position of carbon atom,the system energy is the highest;when Li is located on the projecting position of carbon-carbon bond,the system energy is higher,and when the Li located on the projecting position of benzene ring center,the system possesses the lowest energy and is the most stable.The arm-chair direction is the most probable route for intercalating of Li to graphite cathode;(2) the process of adsorption of Li on the graphite cathode surface is a process of energy storage,too;the position over the center of benzene ring is the most probable adsorption position when Li is close to the graphite surface.The present article provides a very useful image for understanding and improving the charge and discharge properties of the graphite cathode.
    Synthesis of 2-Pyridinecarboxylic Acid by Electrooxidation
    LI Ke-Chang, ZHANG Heng-Bin, CAO Xue-Jing, YU Jian-Guo, ZHANG Yu-Min
    2005, 26(12):  2293-2296 . 
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    2-Pyridinecarboxylic acid was prepared by electrooxidation of 2-methylpyridine. The analysis and isolation of the product were carried out. The influences of reaction conditions, such as the temperature, the anodic potential, the concentrations of sulfuric acid and 2-methylpyridine on the selectivity and the current efficiency were studied. Under the optimum conditions, the highest selectivity is 95.3% and the current efficiency is 45.3%.

    Synthesis of 2-Pyridinecarboxylic Acid by Electrooxidation
    LI Ke-Chang, ZHANG Heng-Bin, CAO Xue-Jing, YU Jian-Guo, ZHANG Yu-Min
    2005, 26(12):  2293-2296,2192. 
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    2-Pyridinecarboxylic acid was prepared by electrooxidation of 2-methylpyridine.The analysis and (isolation) of the product were carried out.The influences of reaction conditions,such as the temperature,the(anodic) potential,the concentrations of sulfuric acid and 2-methylpyridine on the selectivity and the current efficiency were studied.Under the optimum conditions,the highest selectivity is 95.3% and the current efficiency is 45.3%.
    Mechanism for Enhanced Photocatalytic Activity of Titanium Dioxide Film Doped by Mn Under Control
    XU Wei, LI Xin-Jun, ZHENG Shao-Jian, WANG Jun-Gang
    2005, 26(12):  2297-2301 . 
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    The thin films ofTiO2, doped by Mn with different doping modes, were prepared by sol-gel method under process control. The structure of the films was characterized by XPS and SEM. The thin films were evaluated by UV-Vis spectrophotometer and electrochemical workstation. And the activity of the photocatalyst was evaluated by photocatalytic degradation of aqueous methyl orange under UV radiation. The results show that the photocatalytic activity of TiO2thin film can be evidently enhanced by MT doping mode with the optimal dopant mass fraction of 0.80%, on the contrary, decreased by MM doping mode. The characteristic of capacitance-tension characteristic of p-n junction in the film was proved by electrochemical characterization. A mechanism for enhanced photocatalytic activity of titanium dioxide film doped by MT mode was discussed in terms of semiconductor p-n junction theory.

    Mechanism for Enhanced Photocatalytic Activity of Titanium Dioxide Film Doped by Mn Under Control
    XU Wei, LI Xin-Jun, ZHENG Shao-Jian, WANG Jun-Gang
    2005, 26(12):  2297-2301,2193. 
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    The thin films of TiO2,doped by Mn with different doping modes,were prepared by sol-gel method under process control.The structure of the films was characterized by XPS and SEM.The thin films were evaluated by UV-Vis spectrophotometer and electrochemical workstation.And the activity of the photocatalyst was evaluated by photocatalytic degradation of aqueous methyl orange under UV radiation.The results show that the photocatalytic activity of TiO2 thin film can be evidently enhanced by MT doping mode with the optimal dopant mass fraction of 0.80%,on the contrary,decreased by MM doping mode.The characteristic of capacitance-tension characteristic of p-n junction in the film was proved by electrochemical characterization.A mechanism for enhanced photocatalytic activity of titanium dioxide film doped by MT mode was discussed in terms of semiconductor p-n junction theory.
    Phosphoric Acid Doped ab-PBI Membranes and Its Applications in High Temperature PEMFC
    HE Rong-Huan,LI Qing-Feng,BJERRUM Niels J.
    2005, 26(12):  2302-2305. 
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    Poly(2,5-benzimidazole)(ab-PBI) was prepared from 3,4-diaminobenzoic acid via a polymerization reaction. The obtained polymer exhibits an excellent thermal stability at temperatures up to 500 ℃. The membranes of ab-PBI are readily to be doped with phosphoric acid at room temperature. The acid doped ab-PBI membranes present proton conductivity in a level of 10-2-10-1 S/cm at temperatures above 100 ℃. The conductivity of the acid doped ab-PBI membranes was studied in a temperature range of 80 to 200 ℃ under different relative humidities and with different acid doping levels. Proton exchange membrance fuel cell(PEMFC) test results indicated that about 200 mW/cm2 of power density was obtained with phosphoric acid doped ab-PBI as the electrolyte under atmospheric pressure at 200 ℃ and without humidification.

    Phosphoric Acid Doped ab-PBI Membranes and Its Applications in High Temperature PEMFC
    HE Rong-Huan, LI Qing-Feng, BJERRUM Niels J.
    2005, 26(12):  2302-2305,2193. 
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    Poly(2,5-benzimidazole)(ab-PBI) was prepared from 3,4-diaminobenzoic acid via a polymerization reaction.The obtained polymer exhibits an excellent thermal stability at temperatures up to 500 ℃.The membranes of ab-PBI are readily to be doped with phosphoric acid at room temperature.The acid doped ab-PBI membranes present proton conductivity in a level of 10-2-10-1 S/cm at temperatures above 100 ℃.The conductivity of the acid doped ab-PBI membranes was studied in a temperature range of 80 to 200 ℃ under different relative humidities and with different acid doping levels.Proton exchange membrance fuel cell(PEMFC) test results indicated that about 200 mW/cm2 of power density was obtained with phosphoric acid doped ab-PBI as the electrolyte under atmospheric pressure at 200 ℃ and without humidification.
    Mechanism, Configuration and Electronic Structure of ZnO Nanoparticles Formed by Zn Ions Implantation into CaF2 Matrix
    QIU Yong-Qing, LIU Yi-Chun, SHEN De-Zhen, FAN Xi-Wu
    2005, 26(12):  2306-2309. 
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    By implantating high energy Zn ion into CaF2 matrix, the concentration of the implanted ions has a Gaussian′s distribution below the surface of the CaF2, and ZnO quantum dots can be obtained by thermal annealing.Based on the theory of quantum chemistry, using Materials Studio and Gaussian 98 W programs, the electronic structure and optical properties of ZnO nanoparticles on GaF2 matrix were analysized. Selecting four of super-cells from the basal cells of ZnO, the absorption spectra of ZnO were calculated, and the result corresponds to the experimental one. The investigation of electionic structure of ZnO shows that the interaction of ZnO with GaF2 matrix is mainly from the interaction of O atom on ZnO surface with Ca, this interaction leads to the narrow of Fermi energy level and decrease of energy gap. The change of the structure of ZnO surface did not affect the diagnostic absorption spectra, the theoretical results are the same as the experimental ones.

    Mechanism,Configuration and Electronic Structure of ZnO Nanoparticles Formed by Zn Ions Implantation into CaF2 Matrix
    QIU Yong-Qing, LIU Yi-Chun, SHEN De-Zhen, FAN Xi-Wu
    2005, 26(12):  2306-2309,2193. 
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    By implantating high energy Zn ion into CaF2 matrix,the concentration of the implanted ions has a Gaussian's distribution below the surface of the CaF2,and ZnO quantum dots can be obtained by thermal annealing. Based on the theory of quantum chemistry,using Materials Studio and Gaussian 98 W programs,the electronic structure and optical properties of ZnO nanoparticles on GaF2 matrix were analysized.(Selecting) four of super-cells from the basal cells of ZnO,the Absorption spectra of ZnO were calculated,and the result corresponds to the experimental one.The investigation of electionic structure of ZnO shows that the interaction of ZnO with GaF2 matrix is mainly from the interaction of O atom on ZnO surface with Ca,this interaction leads to the narrow of Fermi energy level and decrease of energy gap.The change of the structure of ZnO surface did not affect the diagnostic Absorption spectra,the theoretical results are the same as the experimental ones.
    Modification of DSC Method for Measuring Specific Heat Capacity
    LI Wen-Bo, XUE Feng, CHENG Rong-Shi
    2005, 26(12):  2310-2313. 
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    Specific heat capacity(cp) is a fundamental thermodynamic property. Its traditional measurement method by DSC requires three scans: a baseline scan, a scan using a sapphire standard, and the sample scan. The paper modifies the traditional DSC measurement method to eliminate two sources of error.  Namely they are inequality of the weight of the two empty aluminum pans for sample and reference and the departure of actual heating rate to that of programmed heating rate.  A modified formula considering these two effects is given.  The first term HFT is the ratio of heat flow to actual heating rate; while the second term is a correlation factor that caused by the weight difference of sample and reference aluminum pan.  The modified method offers a significant advance in the ease and reliability of measuring cp for the testing material of water, benzoic acid and potassium chloride.

    Modification of DSC Method for Measuring Specific Heat Capacity
    LI Wen-Bo, XUE Feng, CHENG Rong-Shi
    2005, 26(12):  2310-2313,2193. 
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    Specific heat capacity(cp) is a fundamental thermodynamic property.Its traditional measurement method by DSC requires three scans: a baseline scan,a scan using a sapphire standard,and the sample scan.The paper modifies the traditional DSC measurement method to eliminate two sources of error.Namely they are inequality of the weight of the two empty aluminum pans for sample and reference and the departure of actual heating rate to that of programmed heating rate.A modified formula considering these two effects is given.The first term HFT is the ratio of heat flow to actual heating rate;while the second term is a correlation factor that caused by the weight difference of sample and reference aluminum pan.The modified method offers a significant advance in the ease and reliability of measuring cp for the testing material of water,benzoic acid and potassium chloride.
    Synchrotron Radiation Study of Photoionization and Photodissociation of Freon HFC-134a
    HUANG Chao-Qun, YANG Bin, YANG Rui, WEI Li-Xia, WANG Si-Sheng, SHAN Xiao-Bin, QI Fei, ZHANG Yun-Wu, SHENG Liu-Si, HAO Li-Qing, ZHOU Shi-Kang, WANG Zhen-Ya
    2005, 26(12):  2314-2318. 
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    Photoionization and  photodissociation of HFC-134a were  studied by using synchrotron radiation and a reflectron time-of-flight mass spectrometry(RTOF-MS).  The ionization energy of parent molecule(12. 68±0. 04) eV and appearance potentials of various fragment ions were determined by measuring their photoionization efficiency curves.  Energies, symmetry point groups and ground electronic states of the neutrals and cations of parent and its fragments were calculated by Gaussian-03 program with the G3 method.  According to the theoretical and experimental results, some dissociation channels and their dissociation energies of CH2FCF+3 were analyzed.

    Synchrotron Radiation Study of Photoionization and Photodissociation of Freon HFC-134a
    HUANG Chao-Qun, YANG Bin, YANG Rui, WEI Li-Xia, WANG Si-Sheng, SHAN Xiao-Bin, QI Fei, ZHANG Yun-Wu, SHENG Liu-Si, HAO Li-Qing, ZHOU Shi-Kang, WANG Zhen-Ya
    2005, 26(12):  2314-2318,2193. 
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    Photoionization and photodissociation of HFC-134a were studied by using synchrotron radiation and a reflectron time-of-flight mass spectrometry(RTOF-MS).The ionization energy of parent molecule(12.68±0.04) eV and appearance potentials of various fragment ions were determined by measuring their photoionization efficiency curves.Energies,symmetry point groups and ground electronic states of the neutrals and cations of parent and its fragments were calculated by Gaussian-03 program with the G3 method.According to the theoretical and experimental results,some dissociation channels and their dissociation energies of CH2FCF+3 were analyzed.
    Hybrid Two-dimensional Correlation Infrared Spectrum of  Reversibility of Thermal-induced Phase Transition of Poly(N-isopropylmethacrylamide) in Aqueous Solutions
    WANG Li-Xu,WANG De-Qiu,WU Yu-Qing
    2005, 26(12):  2319-2322. 
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    Temperature-induced reversibility of coil-globule transition was  studied for poly(N-isopropylmethacrylamide)(PNiPMA) in aqueous solutions by means of Fourier transform infrared(FTIR) spectroscopy and hybrid two-dimensional(2D) correlation spectroscopy. The degree of the symmetry along the diagonal line for PNiPMA in sample-sample(SS) hybrid  two-dimensional IR correlation spectrum which  was constructed from IR spectra measured in heating and cooling processes reflects  the  recovery rate of original species, transition temperature, and the rate of the concentration changes during the phase transition. The present study demonstrates a novel application of hybrid  two-dimensional correlation spectroscopy in exploring the reversibility of phase transitions in polymer, such kind of study has a  great potential application to  revealing the phase transition dynamics and molecular interactions of polymers and proteins.

    Hybrid Two-dimensional Correlation Infrared Spectrum of Reversibility of Thermal-induced Phase Transition of Poly(N-isopropylmethacrylamide) in Aqueous Solutions
    WANG Li-Xu, WANG De-Qiu, WU Yu-Qing
    2005, 26(12):  2319-2322,2194. 
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    Temperature-induced reversibility of coil-globule transition was studied for poly(N-isopropylmethacrylamide)(PNiPMA) in aqueous solutions by means of Fourier transform infrared(FTIR) spectroscopy and hybrid two-dimensional(2D) correlation spectroscopy.The degree of the symmetry along the diagonal line for PNiPMA in sample-sample(SS) hybrid two-dimensional IR correlation spectrum which was constructed from IR spectra measured in heating and cooling processes reflects the recovery rate of original species,transition temperature,and the rate of the concentration changes during the phase transition.The present study demonstrates a novel application of hybrid two-dimensional correlation spectroscopy in exploring the reversibility of phase transitions in polymer,such kind of study has a great potential application to revealing the phase transition dynamics and molecular interactions of polymers and proteins.
    Effect of Different Electrode Materials and Different Acid Media on Electrooxidation of 3-Picoline
    ZHANG Yu-Min,ZHANG Heng-Bin,CAO Xue-Jing,XU Yu-Ling,LI Ke-Chang
    2005, 26(12):  2323-2326. 
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    In an electrolytic cell with a proton exchange membrane, it was found from the electrooxidation of 3-picoline at PbO2/Ti, SnO2/Ti, graphite and MnO2/Ti electrodes that PbO2/Ti is a electrode material with the highest catalysis activity in aqueous solution of sulfuric acid. It was found from electrooxidation of 3-picoline in sulfuric, perchloric, phosphoric and acetic acid media  that sulfuric acid is a most satisfied medium for PbO2/Ti electrode. The electrooxidation conditions and electrocatalytic activity were studied with cyclic voltammetry and potentiostatic electrolytic experiments, the current efficiency and the selectivity under various conditions were compared.

    Effect of Different Electrode Materials and Different Acid Media on Electrooxidation of 3-Picoline
    ZHANG Yu-Min, ZHANG Heng-Bin, CAO Xue-Jing, XU Yu-Ling, LI Ke-Chang
    2005, 26(12):  2323-2326,2194. 
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    In an electrolytic cell with a proton exchange membrane,it was found from the electrooxidation of 3-picoline at PbO2/Ti,SnO2/Ti,graphite and MnO2/Ti electrodes that PbO2/Ti is a electrode material with the highest catalysis activity in aqueous solution of sulfuric acid.It was found from electrooxidation of 3-picoline in sulfuric,perchloric,phosphoric and acetic acid media that sulfuric acid is a most satisfied medium for PbO2/Ti electrode.The electrooxidation conditions and electrocatalytic activity were studied with cyclic voltammetry and potentiostatic electrolytic experiments,the current efficiency and the selectivity under various conditions were compared.
    Kinetics of Thermal Decomposition of ZnAc2·2H2Oin Air Atmosphere
    CONG Chang-Jie,LUO Shi-Ting,TAO You-Tian,ZHANG Ke-Li
    2005, 26(12):  2327-2330. 
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    The thermal decomposition processes occurring in the solid state ZnAc2·2H2Owere studied in air atmosphere by using TG-DTG/DTA, DSC and XRD techniques. TG-DTG/DTA, DSC curves show that the decomposition proceeded through two well-defined steps in air atmosphore. Mass loss of the thermal decomposition of ZnAc2·2H2O is in good agreement with the theoretical mass loss. XRD shows that the final product of the thermal decomposition was ZnO. The activation energies were calculated through the Friedman and Flynn-Wall-Ozawa(FWO) methods, and the possible conversion functions were estimated through the multiple-linear regression method. The activation energies for the two decomposition reactions of ZnAc2·2H2Owere 119.82 and 66.82 kJ/mol, respectively.

    Kinetics of Thermal Decomposition of ZnAc2·2H2O in Air Atmosphere
    CONG Chang-Jie, LUO Shi-Ting, TAO You-Tian, ZHANG Ke-Li
    2005, 26(12):  2327-2330,2194. 
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    The thermal decomposition processes occurring in the solid state ZnAc2·2H2O were studied in air atmosphere by using TG-DTG/DTA,DSC and XRD techniques.TG-DTG/DTA,DSC curves show that the decomposition proceeded through two well-defined steps in air atmosphore.Mass loss of the thermal decomposition of ZnAc2·2H2O is in good agreement with the theoretical mass loss.XRD shows that the final product of the thermal decomposition was ZnO.The activation energies were calculated through the Friedman and Flynn-Wall-Ozawa(FWO) methods,and the possible conversion functions were estimated through the multiple-linear regression method.The activation energies for the two decomposition reactions of ZnAc2·2H2O were 119.82 and 66.82 kJ/mol,respectively.
    Influence of Properties of Colored Noise on Stochastic Resonance in Pt(100)/NO+CO Reduction System
    GONG Yu-Bing,HOU Zhong-Huai,XIN Hou-Wen
    2005, 26(12):  2331-2335 . 
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    Under the conditions of constant temperature and the value of NO partial pressure pNO which is tuned close to Hopf bifurcation point, the dynamics of Pt(100)/NO+CO system modulated by colored noise is studied. The colored noise-induced oscillations and the stochastic resonance are observed by using numerical simulations. The influences of intensity and correlation time of colored noise on the stochastic resonance are discussed. A novel result is found that the noise intensity for the occurrence of stochastic resonance initially increases and then decreases with increasing the fixed correlation time.

    Influence of Properties of Colored Noise on Stochastic Resonance in Pt(100)/NO+CO Reduction System
    GONG Yu-Bing, HOU Zhong-Huai, XIN Hou-Wen
    2005, 26(12):  2331-2335,2194. 
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    Under the conditions of constant temperature and the value of NO partial pressure pNO which is tuned close to Hopf bifurcation point,the dynamics of Pt(100)/NO+CO system modulated by colored noise is studied.The colored noise-induced oscillations and the stochastic resonance are observed by using numerical simulations.The influences of intensity and correlation time of colored noise on the stochastic resonance are discussed.A novel result is found that the noise intensity for the occurrence of stochastic resonance initially increases and then decreases with increasing the fixed correlation time.
    Kinetics Study on Diphenylmethane Synthesis Catalyzed by ZnCl2/Clay-SA01
    WU Yun, Zhaorigetu, JIA Mei-Lin, Agula
    2005, 26(12):  2336-2339. 
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    Diphenylmethane was synthesized in the presence of a new environmentally friendly catalyst ZnCl2/Clay-SA01. The effects of loading amount, the molar ratio of benzene to benzyl chloride, amount of catalyst used, reaction temperature and time were investigated. Based on these experiments, the kinetics and mechanism of the reaction were studied. The results show that the reaction is the second order kinetics at 303—318 K. The kinetic equation obtained is r=k[ZnCl2/Clay-SA010.8[C6H6][C6H5CH2Cl] , with an apparent activation energy 88.6 kJ/mol. However, the reaction is the zero order kinetics at 328—353 K. The kinetic equation obtained is r=k[ZnCl2/Clay-SA010.1 with the apparent activation energy 52.8 kJ/mol. The model should be used to provide a theoretical explanation of reaction mechanism and to be applied to the development of industrial process.

    Kinetics Study on Diphenylmethane Synthesis Catalyzed by ZnCl2/Clay-SA01
    WU Yun, Zhaorigetu, JIA Mei-Lin, Agula
    2005, 26(12):  2336-2339,2194. 
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    Diphenylmethane was synthesized in the presence of a new environmentally friendly catalyst ZnCl2/Clay-SA01.The effects of loading amount,the molar ratio of benzene to benzyl chloride,amount of catalyst used,reaction temperature and time were investigated.Based on these experiments,the kinetics and mechanism of the reaction were studied.The results show that the reaction is the second order kinetics at 303—318 K.The kinetic equation obtained is r=k[ZnCl2/Clay-SA01]0.8[C6H6][C6H5CH2Cl],with an apparent activation energy 88.6 kJ/mol.However,the reaction is the zero order kinetics at 328—353 K.The kinetic equation obtained is r=k[ZnCl2/Clay-SA01]0.1 with the apparent activation energy 52.8 kJ/mol.The model should be used to provide a theoretical explanation of reaction mechanism and to be applied to the development of industrial process.
    ESI-MSn Behavior and Quantum Chemistry Calculation of Stability of Fragment Ions of Diester-diterpenoid Alkaloids(DDA)
    CHEN Lan-Hui,JIN Lian-Ji,SU Zhong-Min,QIU Yong-Qing,WANG Yong,LIU Shu
    2005, 26(12):  2340-2344. 
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    Quantum chemistry calculations were carried out to theoretically analyze the stability of fragments and the rules of elimination of substituents in electrospray ionization tandem mass spectra(ESI-MSn) for DDA. Geometries of the six DDA were optimized at ab initio HF/6-31G* level. The calculations provided the binding energies of the corresponding active bonds and the comparison of the data gave the criterion about the stability of chemical bonds. The order of eliminations of carboxyl, benzyl, ethyl or methyl as well as the influence on eliminations of ·OH at C3 on the atoms around also studied. The process of elimination of CO and the rules of elimination of four methoxy groups on different carbon atoms were predicted theoretically. The results of Quantum chemistry calculation were in pretty agreement with the experimental data of ESI-MSn.

    ESI-MSn Behavior and Quantum Chemistry Calculation of Stability of Fragment Ions of Diester-diterpenoid Alkaloids(DDA)
    CHEN Lan-Hui, JIN Lian-Ji, SU Zhong-Min, QIU Yong-Qing, WANG Yong, LIU Shu-Ying
    2005, 26(12):  2340-2344,2195. 
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    Quantum chemistry calculations were carried out to theoretically analyze the stability of fragments and the rules of elimination of substituents in electrospray ionization tandem mass spectra(ESI-MSn) for DDA.Geometries of the six DDA were optimized at ab initio HF/6-31G* level.The calculations provided the binding energies of the corresponding active bonds and the comparison of the data gave the criterion about the stability of chemical bonds.The order of eliminations of carboxyl,benzyl,ethyl or methyl as well as the influence on eliminations of.OH at C3 on the atoms around also studied.The process of elimination of CO and the rules of elimination of four methoxy groups on different carbon atoms were predicted theoretically.The results of Quantum chemistry calculation were in pretty agreement with the experimental data of ESI-MSn.
    Application of the ABEEM/MM Model to Simulate Molecule of Protein(Crambin)
    ZHANG Jiang, YANG Zhong-Zhi
    2005, 26(12):  2345-2347. 
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    The ABEEM/MM model(atom-bond electronegativity equalization method fused into molecular mechanics) is built for protein. The Lennard-Jones and torsional parameters were optimized to be consistent with the ABEEM/MM fluctuating charge electrostatic potential. The ABEEM/MM fluctuating charge model reproduces both the peptide conformational energies and structures with a satisfactory accuracy but in a low computer cost. We applied it to a reaslistic protein(crambin) to test our model and the parameters. The results of energy minimizations of crambin demonstrate that using our model can obtain more reasonable structural properties than using other force fields listed in this letter comparing with experimental crystal data.

    Application of the ABEEM/MM Model to Simulate Molecule of Protein(Crambin)
    ZHANG Qiang, YANG Zhong-Zhi
    2005, 26(12):  2345-2347,2195. 
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    The ABEEM/MM model(atom-bond electronegativity equalization method fused into molecular mechanics) is built for protein.The Lennard-Jones and torsional parameters were optimized to be consistent with the ABEEM/MM fluctuating charge electrostatic potential.The ABEEM/MM fluctuating charge model reproduces both the peptide conformational energies and structures with a satisfactory accuracy but in a low computer cost.We applied it to a reaslistic protein(crambin) to test our model and the parameters.The results of energy minimizations of crambin demonstrate that using our model can obtain more reasonable structural properties than using other force fields listed in this letter comparing with experimental crystal data.
    Letter
    Highly Effective Sb2O3/Co-ZSM-5 Catalysts for Ethane Ammoxidation
    PAN Wei-Cheng, LIAN Hong-Lei, JIA Ming-Jun, ZHANG Wen-Xiang, JIANG Da-Zhen
    2005, 26(12):  2348-2350 . 
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    The catalytic ammoxidation of ethane with oxygen and ammonia was investigated over a series Sb2O3 promoted ion-exchanged Co-ZSM-5 zeolites(Sb2O3/Co-ZSM-5).The introduction of appropriate amount of Sb2O3can considerably improve the conversion of ethane,suppress the formation of COx,and increase the total C2 selectivity to acetonitrile and ethylene.Among them,the sample with 5% Sb2O3loading(in mass fraction) shows a 68.4% ethane conversion at 550 ℃,a 51.6% selectivity to acetonitrile and a 31.7% selectivity to ethylene,and a 35.3% yield of acetonitrile were obtained,which is to our knowledge the highest ever reported for the direct ammoxidation of ethane.

    Articles
    Highly Effective Sb2O3/Co-ZSM-5 Catalysts for Ethane Ammoxidation
    PAN Wei-Cheng, LIAN Hong-Lei, JIA Ming-Jun, ZHANG Wen-Xiang, JIANG Da-Zhen
    2005, 26(12):  2348-2350,2197. 
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    The catalytic ammoxidation of ethane with oxygen and ammonia was investigated over a series(Sb2O3) promoted ion-exchanged Co-ZSM-5 zeolites(Sb2O3/Co-ZSM-5).The introduction of appropriate amount of Sb2O3 can considerably improve the conversion of ethane,suppress the formation of COx,and increase the total C2 selectivity to acetonitrile and ethylene.Among them,the sample with 5% Sb2O3 loading(in mass fraction) shows a 68.4% ethane conversion at 550 ℃, a 51.6% selectivity to acetonitrile and a 31.7% selectivity to ethylene,and a 35.3% yield of acetonitrile were obtained,which is to our knowledge the highest ever reported for the direct ammoxidation of ethane.
    Letter
    IR Spectroscopic Study on Selective Adsorption of Sulfur-containing Compounds from Gasoline Distillation on Copper-exchanged Y Zeolite
    TIAN Fu-Ping,WU Wei-Cheng,JIANG Zong-Xuan,YANG Yong-Xing,CAI Tian-Xi,LI Can
    2005, 26(12):  2351-2353 . 
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    Desulfurization of gasoline distillation with adsorption was studied at ambient temperature and pressure by using CuNaY(NaY exchanged with copper nitrate aqueous solution) as the adsorbents.The gasoline distillation was composed of thiophene-cyclohexane solution(115.0 μg/mL) with or without toluene.For the solution without toluene,no detectable sulfur was found in the effluent when the effluent volume was less than 40 mL,while the addition of toluene resulted in an evident drop of the adsorption performance for CuNaY.FTIR spectra indicate that the conversion of Cu2+ to Cu+ took place during the pretreatment of CuNaY adsorbent,and the interaction mode between the adsorbed thiophene molecules and Cu+ is π complexation.This adsorption mode is easily affected by aromatic compounds,resulting in the significant decrease of adsorption capacity in model gasoline containing toluene on CuNaY.

    Articles
    IR Spectroscopic Study on Selective Adsorption of Sulfur-containing Compounds from Gasoline Distillation on Copper-exchanged Y Zeolite
    TIAN Fu-Ping, WU Wei-Cheng, JIANG Zong-Xuan, YANG Yong-Xing, CAI Tian-Xi, LI Can
    2005, 26(12):  2351-2353,2197. 
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    Desulfurization of gasoline distillation with adsorption was studied at ambient temperature and pressure by using CuNaY(NaY exchanged with copper nitrate aqueous solution) as the adsorbents.The gasoline distillation was composed of thiophene-cyclohexane solution(115.0 μg/mL) with or without toluene.For the solution without toluene,no detectable sulfur was found in the effluent when the effluent volume was less than 40 mL,while the addition of toluene resulted in an evident drop of the adsorption performance for(CuNaY.) FTIR spectra indicate that the conversion of Cu(2+) to Cu+ took place during the pretreatment of(CuNaY) adsorbent,and the interaction mode between the adsorbed thiophene molecules and Cu+ is π complexation.This adsorption mode is easily affected by aromatic compounds,resulting in the significant decrease of adsorption capacity in model gasoline containing toluene on CuNaY.
    Letter
    Density Functional Study of NO Adsorption and Direct Decomposition on Rh(100) and Rh(111) Surfaces
    TU Xue-Yan,TIAN Kai,DAI Shu-Shan
    2005, 26(12):  2354-2356 . 
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    The chemisorption and direct decomposition of NO on Rh(100) and Rh(111) surfaces were studied by the density functional theory(DFT) with Dmol3 program.The calculation results show that for the Rh(100)surface,the bridge sites are found to be the preferred adsorption site,but for the Rh(111) surface,the three fold hollow(hcp) sites are found to be the most stable one; the transition states were confirmed for the direct decomposition of  NO on Rh(100) and Rh(111) surfaces by successful transition state search,and the activation energy are 161.91 kJ/mol for Rh(100) and 183.72 kJ/mol for Rh(111),respectively.

    Articles
    Density Functional Study of NO Adsorption and Direct Decomposition on Rh(100) and Rh(111) Surfaces
    TU Xue-Yan, TIAN Kai, DAI Shu-Shan
    2005, 26(12):  2354-2356,2197. 
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    The chemisorption and direct decomposition of NO on Rh(100) and Rh(111) surfaces were studied by the density functional theory(DFT) with Dmol3 program.The calculation results show that for the Rh(100)surface,the bridge sites are found to be the preferred adsorption site,but for the Rh(111) surface,the three fold hollow(hcp) sites are found to be the most stable one;the transition states were confirmed for the direct decomposition of NO on Rh(100) and Rh(111) surfaces by successful transition state search,and the activation energy are 161.91 kJ/mol for Rh(100) and 183.72 kJ/mol for Rh(111),respectively.
    Letters
    Studies on Synthesis of a New Hexagonal Copper Aluminophosphate and Its Catalytic Behavior for Phenol Hydroxylation
    QI Xing-Yi,WANG Zhi-Yong,ZHANG Li-Li,FAN Xue-Tao,XIE Wen-Hua,FENG Zhi-Hua
    2005, 26(12):  2357-2359. 
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    A new type of non-soluble copper aluminophosphate(denoted as CuAlPO) was synthesized by static hydrothermal crystallization and characterized by using several physicochemical techniques.XRD analysis reveals that CuAlPO can be obtained from a reactive gel of molar composition: iso-Pr2NH∶0.3CuO∶0.7Al2O3∶P2O5∶80H2O in a Teflon-lined stainless steel autoclave at 180℃ for 72 h and has the same crystal structure as that of hexagonal SiO2(JCPDS No.83-2299).The sources of CuO,Al2O3 and P2O5 were copper sulfate pentahydrate,aluminum isopropoxide and o-phosphoric acid(mass fraction:85%),respectively.SEM shows a characteristic hexagonal morphology and a crystallite size of about 2μm for both the as-synthesized CuAlPO and the calcined CuAlPO(550℃,6h).Low specific surace area(2.0 m2/g) and pore volume(0.004 mL/g) of CuAlPO were observed by N2-adsorption measurement.Catalytic evaluation tests demonstrate that an excellent transformation of phenol into catechol and hydroquinone over the material was achieved in water under the benign reaction conditions with a phenol conversion of 295% being observed at room temperature(30℃).

    Articles
    Studies on Synthesis of a New Hexagonal Copper Aluminophosphate and Its Catalytic Behavior for Phenol Hydroxylation
    QI Xing-Yi, WANG Zhi-Yong, ZHANG Li-Li, FAN Xue-Tao, XIE Wen-Hua, FENG Zhi-Hua
    2005, 26(12):  2357-2359,2198. 
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    A new type of non-soluble copper aluminophosphate(denoted as CuAlPO) was synthesized by(static) hydrothermal crystallization and characterized by using several physicochemical techniques.XRD analysis reveals that CuAlPO can be obtained from a reactive gel of molar composition: iso-Pr2NH∶0.3CuO∶(0.7Al2O3∶)P2O5∶80H2O in a Teflon-lined stainless steel autoclave at 180 ℃ for 72 h and has the same crystal structure as that of hexagonal SiO2(JCPDS No.83-2299).The sources of CuO,Al2O3 and P2O5 were copper sulfate pentahydrate,aluminum isopropoxide and o-phosphoric acid(mass fraction: 85%),respectively.SEM shows a characteristic hexagonal morphology and a crystallite size of about 2 μm for both the as-synthesized CuAlPO and the calcined CuAlPO(550 ℃,6h).Low specific surace area(2.0 m2/g) and pore volume(0.004 mL/g) of CuAlPO were observed by N2-adsorption measurement.Catalytic evaluation tests demonstrate that an excellent transformation of phenol into catechol and hydroquinone over the material was achieved in water under the benign reaction conditions with a phenol conversion of 29.5% being observed at room temperature(30 ℃).
    Terpolymerization of Carbon Dioxide, Propylene Oxide and Cyclohexene Oxide Catalyzed  by Rare-earth Ternary Catalyst
    XIE Dong, QUAN Zhi-Long, WANG Xian-Hong, ZHAO Xiao-Jiang, WANG Fu-Song
    2005, 26(12):  2360-2362. 
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    Y(CCl3COO)3/ZnR2/Glycerol was used for the terpolymerization of carbon dioxide(CO2), propylene oxide(PO), and cyclohexene oxide(CHO). The cyclohexene carbonate content and the syndiotactic structure of the terpolymer increases with the increase of CHO content.The terpolymer is a random block copolymer of poly(propylene carbonate) and poly(cyclohexene carbonate), and the  introduction of CHO in the terpolymer could significantly improve the thermal stability.

    Terpolymerization of Carbon Dioxide,Propylene Oxide and Cyclohexene Oxide Catalyzed by Rare-earth Ternary Catalyst
    XIE Dong, QUAN Zhi-Long, WANG Xian-Hong, ZHAO Xiao-Jiang, WANG Fo-Song
    2005, 26(12):  2360-2362,2195. 
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    Y(CCl3COO)3/ZnR2/Glycerol was used for the terpolymerization of carbon dioxide(CO2),propylene oxide(PO),and cyclohexene oxide(CHO).The cyclohexene carbonate content and the syndiotactic structure of the terpolymer increases with the increase of CHO content.The terpolymer is a random block copolymer of poly(propylene carbonate) and poly(cyclohexene carbonate),and the introduction of CHO in the terpolymer could significantly improve the thermal stability.
    Preparation of Cibacron Blue F3GA Attached Chitosan Microspheres and Their Adsorption Properties for Bovine Serum Albumin(BSA)
    ZHANG Jing, ZHANG Zheng-Pu, SONG Yu, HE Bing-Kun
    2005, 26(12):  2363-2368. 
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    A series of novel aminated chitosan microbeads were prepared from chitosan through inverse suspension crosslinking, hydroxylpropyl-chlorination and amination. Affinity dye-ligand, Cibacron Blue F3GA, was covalently coupled with the aminated chitosan microspheres via space arm between the triazine ring of Cibacron Blue F3GA and the amino groups of the microspheres. The maximum attachment of Cibacron Blue F3GA was 494 μmol/g by changing the crosslinking degree of the microspheres. Albumin adsorption onto Cibacron Blue F3GA-attached chitosan microspheres was investigated. The BSA equilibrium adsorption capacity was 95.2 mg/g dry beads. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The highest desorption ratio(over 99%) was achieved by using 1.0 mol/L NaSCN(pH=8.0). The Cibacron Blue F3GA-attached chitosan microspheres could be reused without significant decreases in the adsorption capacities.

    Preparation of Cibacron Blue F3GA Attached Chitosan Microspheres and Their Adsorption Properties for Bovine Serum Albumin(BSA)
    ZHANG Jing, ZHANG Zheng-Pu, SONG Yu, HE Bing-Kun
    2005, 26(12):  2363-2368,2195. 
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    A series of novel aminated chitosan microbeads were prepared from chitosan through inverse suspension crosslinking,hydroxylpropyl-chlorination and amination.Affinity dye-ligand,Cibacron Blue F3GA,was covalently coupled with the aminated chitosan microspheres via space arm between the triazine ring of Cibacron Blue F3GA and the amino groups of the microspheres.The maximum attachment of Cibacron Blue F3GA was 494 μmol/g by changing the crosslinking degree of the microspheres.Albumin adsorption onto Cibacron Blue F3GA-attached chitosan microspheres was investigated.The BSA equilibrium adsorption capacity was 95.2 mg/g dry beads.The adsorption phenomena appeared to follow a typical Langmuir isotherm.The highest desorption ratio(over 99%) was achieved by using 1.0 mol/L NaSCN(pH=8.0).The Cibacron Blue F3GA-attached chitosan microspheres could be reused without significant decreases in the adsorption capacities.
    Preparation of Fluorescent Hyperbranched Poly(aryl ether ketone)s via A2+B3 Reaction
    MU Jian-Xin, ZHANG Chun-Ling, WANG Gui-Bin, CHEN Jie, JIANG Zhen-Hua
    2005, 26(12):  2369-2372. 
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    Hyperbranched poly(aryl ether ketone)s(HPETFDEK-F) were synthesized from the combination of 3,3′,5,5′, -tetramethyl biphenyl-4,4′-diol(A2) and B3,  a novel monomer 1,3,5-tris\[4-(4-flourobenzoyl)phenoxy\] benzene synthesized in our lab.  The FHPETFDEK was prepared by an end-capping approach.  The chemical structure of such a polymer was confirmed by 1H NMR,  FTIR,  DSC and TGA.  The UV and fluorescent spectra of FHPETFDEK were studied and fluorescence phenomena were observed.

    Preface
    Preparation of Fluorescent Hyperbranched Poly(aryl ether ketone)s via A2+B3 Reaction
    MU Jian-Xin, ZHANG Chun-Ling, WANG Gui-Bin, CHEN Jie, JIANG Zhen-Hua
    2005, 26(12):  2369-2372,2195. 
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    Hyperbranched poly(aryl ether ketone)s(HPETFDEK-F) were synthesized from the combination of 3,3',5,5',-tetramethyl biphenyl-4,4'-diol(A2) and B3,a novel monomer 1,3,5-tris[4-(4-flourobenzoyl)phenoxy] benzene synthesized in our lab.The FHPETFDEK was prepared by an end-capping approach.The chemical structure of such a polymer was confirmed by 1H NMR,FTIR, DSC and TGA.The UV and fluorescent spectra of FHPETFDEK were studied and fluorescence phenomena were observed.
    Articles
    Preparation and Structure Morphology of Poly(vinyl alcohol)/Silica Hybrid Materials Membranes Based on Electrospun Fibers
    SHI Tie-Jun, ZHOU Yu-Bo, LIAO Ruo-Gu, WANG Hua-Lin
    2005, 26(12):  2373-2376 . 
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    The spin solutions of poly(vinyl alcohol)/silica  hybrid materials with different silica contents were prepared by sol-gel method, then fiber membranes were obtained by electrospinning. XRD result indicated that the degree of crystallinity of hybrid electrospun fiber membranes declined comparing with pure PVA electrospun fiber membrane. FTIR showed that hydroxyl in PVA condensed with hydroxyl of hydrolyzing tetraethoxysilane, the fiber material with a network configuration existed. SEM revealed that when PVA/SiO2 mass ratio was 4∶1, the fibers smoothed and uniformed. With increasing of silica content, fiber diameter became fine and spindly beads increased. The fiber diameter became fine and round beads increased after adding electrolyte NaCl and MgCl2. The forming mechanism of the fiber structure morphology  was analyzed theoretically.

    Preface
    In Situ FTIR Spectroscopic Investigation on the Curing Reaction of Binaphthyl Epoxy Systems
    XU Kai, CHEN Ming-Cai, ZHANG Xiu-Ju, LIU Hong-Bo
    2005, 26(12):  2373-2376,2196. 
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    An investigation on the curing reactions of 2,2'-diglycidyl-1,1'-binaphthyl(DGEBN) systems containing amino and phenolic hardeners was carried out by in situ Fourier transform infrared(FTIR) spectroscopy.The shifts in frequency of epoxy stretching vibration to lower values in the uncured systems suggest the existences of specific intermolecular interactions,including hydrogen bonding by solvent-mixing the cure formulations.The hydrogen-bonded intermediate complexes consisting of epoxy and the reactive groups of hardeners were thought to include cyclic structures.As the reactions progressed,a new peak emerged between 914-916 cm-1,which is associated with "free" epoxy groups.This emergence is related to the theoretical gel point.The four hardeners showed different reactivities towards DGEBN.The kinetic analysis derived from FTIR data was in good agreement with the result obtained by DSC method.
    Articles
    In Situ FTIR Spectroscopic Investigation on the Curing Reaction of Binaphthyl Epoxy Systems  
    XU Kai, CHEN Ming-Cai, ZHANG Xiu-Ru, LIU Hong-BO
    2005, 26(12):  2377-2380 . 
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    An investigation on the curing reactions of 2,2′-diglycidyl-1,1′-binaphthyl (DGEBN) systems containing amino and phenolic hardeners was carried out by in situ Fourier transform infrared (FTIR) spectroscopy. The shifts in frequency of epoxy stretching vibration to lower values in the uncured systems suggest the existences of specific intermolecular interactions, including hydrogen bonding by solvent-mixing the cure formulations. The hydrogen-bonded intermediate complexes consisting of epoxy and the reactive groups of hardeners were thought to include cyclic structures. As the reactions progressed, a new peak emerged between 914-916  cm-1, which is associated with “free” epoxy groups. This emergence is related to the theoretical gel point. The four hardeners showed different reactivities towards DGEBN. The kinetic analysis derived from FTIR data was in good agreement with the result obtained by DSC method.

    Preparation and Structure Morphology of Poly(vinyl alcohol)/Silica Hybrid Materials Membranes Based on Electrospun Fibers
    SHI Tie-Jun, ZHOU Yu-Bo, LIAO Ruo-Gu, WANG Hua-Lin
    2005, 26(12):  2377-2380,2195. 
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    The spin solutions of poly(vinyl alcohol)/silica hybrid materials with different silica contents were prepared by sol-gel method,then fiber membranes were obtained by electrospinning.XRD result indicated that the degree of crystallinity of hybrid electrospun fiber membranes declined comparing with pure PVA electrospun fiber membrane.FTIR showed that hydroxyl in PVA condensed with hydroxyl of hydrolyzing tetraethoxysilane,the fiber material with a network configuration existed.SEM revealed that when PVA/SiO2 mass ratio was 4∶1,the fibers smoothed and uniformed.With increasing of silica content,fiber diameter became fine and spindly beads increased.The fiber diameter became fine and round beads increased after adding electrolyte NaCl and MgCl2.The forming mechanism of the fiber structure morphology was analyzed theoretically.
    Self-aggregation Behavior of Amphiphilic Block Copolymer PSt-b-PAA in Toluene
    SHANG Zhi-Zhong, GAO Bao-Jiao, HE San-Xiong
    2005, 26(12):  2381-2385. 
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    The block copolymer of PSt-b-PBA with well-defined structure was synthesized via atom transfer radical polymerization(ATRP) by using 1-phenylethyl bromide(1-PEBr) as the initiator, cuprous bromide as the catalyst, 2,2′-bipyridine(bpy) as the ligand and xylene as the solvent. The block copolymer PSt-b-PBA was characterized and the living polymerization was validated by GPC, FTIR, and 1H NMR. Then the amphiphilic block copolymer of PSt-b-PAA was prepared by alkaline hydrolysis of PSt-b-PBA. The reversed micellization behavior of PSt-b-PAA in toluene was investigated by fluorescence probe technique with  polar fluorescence compound N-(1-naphthyl)ethylenediamine dihydrochloride(NEAH) as a polar fluorescence probe and by the observation of TEM. It was found that NEAH as a polar fluorescence compound can clearly reveal the reversed micellization behavior of PSt-b-PAA in toluene. The results show that the reversed micelles which have hydrophilic core and hydrophobic shell can formed spontaneously through self-aggregation of PSt-b-PAA macromolecules in toluene, the aggregates have the morphology of sphere, and the self-aggregation behavior of PSt-b-PAA depends apparently on the microstructure of the macromolecules and the temperature. The longer the PAA block is, the lower the critical micelle concentration is; the higher the temperature is, the lower the critical micelle concentration is.

    Self-aggregation Behavior of Amphiphilic Block Copolymer PSt-b-PAA in Toluene
    TANG Zhi-Zhong, GAO Bao-Jiao, HE San-Xiong
    2005, 26(12):  2381-2385,2196. 
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    The block copolymer of PSt-b-PBA with well-defined structure was synthesized via atom transfer radical polymerization(ATRP) by using 1-phenylethyl bromide(1-PEBr) as the initiator,cuprous bromide as the catalyst,2,2'-bipyridine(bpy) as the ligand and xylene as the solvent.The block copolymer PSt-b-PBA was characterized and the living polymerization was validated by GPC,FTIR,and 1H NMR.Then the amphiphilic block copolymer of PSt-b-PAA was prepared by alkaline hydrolysis of PSt-b-PBA.The reversed micellization behavior of PSt-b-PAA in toluene was investigated by fluorescence probe technique with polar fluorescence compound N-(1-naphthyl)ethylenediamine dihydrochloride(NEAH) as a polar fluorescence probe and by the observation of TEM.It was found that NEAH as a polar fluorescence compound can clearly reveal the reversed micellization behavior of PSt-b-PAA in toluene.The results show that the reversed micelles which have hydrophilic core and hydrophobic shell can formed spontaneously through self-aggregation of PSt-b-PAA macromolecules in toluene,the aggregates have the morphology of sphere,and the self-aggregation behavior of PSt-b-PAA depends apparently on the microstructure of the macromolecules and the temperature.The longer the PAA block is,the lower the critical micelle concentration is;the higher the temperature is,the lower the critical micelle concentration is.
    Crystalline Structure of Polypropylene Catalloys and Related Influence Factors
    SHANG Guan-Yong-Gang, ZHENG Qiang, BANG Mao, WANG Hui-Jun, ZHANG Ming-Qiu
    2005, 26(12):  2386-2390. 
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    Crystalline structures of two types of polypropylene catalloys(PP-c) containing different ethylene contents were investigated by differential scanning calorimeter(DSC) and wide-angle X-ray diffraction(WAXD). When the PEP40  containing higher ethylene content crystallizes isothermally in the temperature range investigated, double melting peaks appear in each endotherm region. WAXD measurement evidences that the behavior results from the coexistence of α-form and β-form of PP crystals. The calculated results show that the β-crystal content in PEP40  depends on the crystallization temperature and the β-crystal content of them crystallized at 124℃ approaches the maximum. In addition, the thermal treatment at 220℃ greatly increases the β-crystal content in PEP40 samples and induces the existence of β-crystal in PEP20 samples. Compared with those being treated thermally at 200℃, the PEP20 samples crystallized isothermally at 124℃ after being treated thermally at 220℃ for 30 min exhibit smaller crystalline size and clear morphology of β-spherulite.

    Crystalline Structure of Polypropylene Catalloys and Related Influence Factors
    SHANGGUAN Yong-Gang, ZHENG Qiang, PENG Mao, WANG Hui-Jun, ZHANG Ming-Qiu
    2005, 26(12):  2386-2390,2196. 
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    Crystalline structures of two types of polypropylene catalloys(PP-c) containing different ethylene contents were investigated by differential scanning calorimeter(DSC) and wide-angle X-ray diffraction(WAXD).When the PEP40 containing higher ethylene content crystallizes isothermally in the temperature range investigated,double melting peaks appear in each endotherm region.WAXD measurement evidences that the behavior results from the coexistence of α-form and β-form of PP crystals.The calculated results show that the β-crystal content in PEP40 depends on the crystallization temperature and the β-crystal content of them crystallized at 124 ℃ approaches the maximum.In addition,the thermal treatment at 220 ℃ greatly increases the β-crystal content in PEP40 samples and induces the existence of β-crystal in PEP20 samples.Compared with those being treated thermally at 200 ℃,the PEP20 samples crystallized isothermally at 124 ℃ after being treated thermally at 220 ℃ for 30 min exhibit smaller crystalline size and clear morphology of β-spherulite.
    Letter
    Observation of Novel Spherulitic Morphology Formed in Extended-chain Crystals in High-pressure Crystallized PET/PC Blends
    LV Jun,WEI Gang,HUANG Rui,LI Liang-Bin
    2005, 26(12):  2391-2393 . 
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    High-pressure crystallization behavior of poly(ethylene terephthalate)(PET)/biphenol-A polycarbonate(PC) blends were investigated by scanning electron microscopy(SEM) and atomic force microscopy(AFM).Two novel spherulitic structures,i.e.bamboo-shoot-like spherulite and brain-like spherulite,were observed in the polyester extended-chain crystals.The extended-chain lamellar crystal may be the substructure of these spherulites.This morphology,which is quite different from that of usual spherulite and extended-chain crystal,may promote the understanding of formation process and mechanism for both polymer spherulites and extended-chain crystals.

    Articles
    Observation of Novel Spherulitic Morphology Formed in Extended-chain Crystals in High-pressure Crystallized PET/PC Blends
    LV Jun, WEI Gang, HUANG Rui, LI Liang-Bin
    2005, 26(12):  2391-2393,2197. 
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    High-pressure crystallization behavior of poly(ethylene terephthalate)(PET)/biphenol-A polycarbonate(PC) blends were investigated by scanning electron microscopy(SEM) and atomic force microscopy(AFM).Two novel spherulitic structures,i.e.bamboo-shoot-like spherulite and brain-like spherulite,were observed in the polyester extended-chain crystals.The extended-chain lamellar crystal may be the substructure of these spherulites.This morphology,which is quite different from that of usual spherulite and extended-chain crystal,may promote the understanding of formation process and mechanism for both polymer spherulites and extended-chain crystals.
    Letters
    Effects of Crystallinity on Hydrolytic Depolymerization of PET Under Microwave Irradiation
    LIU Li-Xin,LIU Ruo-Wang,ZHANG Dong,AN Li-Jia,WANG Yu
    2005, 26(12):  2394-2396. 
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    Polyethylene terephthalate(PET) resin was hydrolyzed to terephthalate acid(TPA) and ethylene glycol(EG) under microwave irradiation.The effects of crystallinity on the depolymerization of PET was investigated.PET resin was isothermal crystallized at temperature of 140,170,200 and 230℃ for 5 hours,the crystallinity of the resin was 25.7%,29.5%,33.9% and 40.6%,respectively,then the resin with different crystallinity was hydrolyzed under microwave irriadition. Under the same conditions of hydrolytic depolymerization,the degree of PET depolymerization decreased from 72.8% to 69.34% with the increase of crystallinity of PET resin,the rate of depolymerization varied little with the increasing of crystallinity of PET,this indicated that the crystallinity of PET has little effect on the hydrolytic depolymerization.The crystallinity of PET was increased during the temperature elevating process of the hydrolytic depolymerization.Investigation by DSC proved that the crystallinity of PET resin increased notability during the same temperature elevating process as the hydrolyzed depolymerization.According to the theory that depolymerization was firstly proceed in the amorphous phase,the crystallinity should increase during the reaction.However,the crystallinity of PET residue was decreased during all the reaction process,this indicates that the hydrolysis did  not preferentially occur in the amorphous phase.

    Articles
    Effects of Crystallinity on Hydrolytic Depolymerization of PET Under Microwave Irradiation
    LIU Li-Xin, LIU Ruo-Wang, ZHANG Dong, AN Li-Jia, WANG Yu
    2005, 26(12):  2394-2396,2198. 
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    Polyethylene terephthalate(PET) resin was hydrolyzed to terephthalate acid(TPA) and ethylene glycol(EG) under microwave irradiation.The effects of crystallinity on the depolymerization of PET was investigated.PET resin was isothermal crystallized at temperature of 140,170,200 and 230 ℃ for 5 hours,the crystallinity of the resin was 25.7%,29.5%,33.9% and 40.6%,respectively,then the resin with different crystallinity was hydrolyzed under microwave irriadition. Under the same conditions of hydrolytic depolymerization, the degree of PET depolymerization decreased from 72.8% to 69.34% with the increase of crystallinity of PET resin,the rate of depolymerization varied little with the increasing of crystallinity of PET,this indicated that the crystallinity of PET has little effect on the hydrolytic depolymerization.The crystallinity of PET was increased during the temperature elevating process of the hydrolytic depolymerization.Investigation by DSC proved that the crystallinity of PET resin increased notability during the same temperature elevating process as the hydrolyzed depolymerization.According to the theory that depolymerization was firstly proceed in the amorphous phase,the crystallinity should increase during the reaction.However,the crystallinity of PET residue was decreased during all the reaction process,this indicates that the hydrolysis did not preferentially occur in the amorphous phase.