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    10 December 2007, Volume 28 Issue 12
    目次
    下期目次预览
    2007, 28(12):  0.  doi:
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    高等学校化学学报2007年第28卷第12期目次
    2007, 28(12):  0.  doi:
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    高等学校化学学报第28卷(1~12期)学科分类目次
    2007, 28(12):  0.  doi:
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    研究论文
    Preparation of Aligned Carbon Nanotube Arrays by Pyrolysis of Iron(Ⅱ) Phthalocyanine and Ethylene
    PENG Ai-Ping1,2, ZHANG Hao3, WANG Zhi-Yong2, SHI Zu-Jin2, GU Zhen-Nan2*,CAO Gao-Ping3, GAO Li-Jun1*
    2007, 28(12):  2229-2233.  doi:
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    Aligned carbon nanotube arrays(ACNTA) with 210 μm in length were prepared by pyrolysis of iron(Ⅱ) phthalocyanine(FePc)and ethylene(C2H4). The as-grown ACNTA, which were well-aligned and pure, were characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM), Raman spectrum and X-ray photoelectron spectroscopy(XPS). The influence of experimental conditions, such as temperature, growth time, and flow rate of C2H4 on the formation of ACNTA were systematically investigated. The results indicate that 800 ℃ was the most suitable temperature for the preparation of long ACNTA by pyrolysis of FePc and C2H4 , the activity of catalyst could be kept for a rather long time(60 min), the addition of C2H4 significantly enhanced the growth speed of ACNTA and 50 cm3/min was found to be the optimal flow rate for the formation of ACNTA.
    Preparation and Modification of Supported Nano Cu/Fe Bimetal Alloy in Ethanol-water Solution and Its Reduction-chlorination Property for Trichloroethylene
    ZHANG Huan1*, JIN Zhao-Hui2, LI Tie-Long2
    2007, 28(12):  2234-2238.  doi:
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    Supported nano Cu/Fe bimetal alloy with a spherical nanocluster structure was synthesized in ethanol-water solution by using KBH4 as the reducing agent and Cu as the complex metal when micro-scale graphite was used as a support material. This supported nano bimetal alloy showed the better reductive dechlorination property for trichloroethylene than the supported nano Fe0 in the solution. TCE of 10 mg/L was completely removed in 5 h when Fe0 dosage was 10 g/L. The cationic surfactant cetyltrimethyl ammonium bromide(CTAB) was used to modify the surface of the supported nano bimetal alloy. The reduction effect of the material for TCE was enhanced after being modified. During the 36 d of continuous dechlorination, the modified supported nano bimetal alloy shows a highly stable property for TCE removal. The experiment results show that 10.2 mg/L TCE could be completely reduced in 7 h by the supported nano bimetal alloy in the 36th day.
    Preparation and Magnetic Properties of Single-crystal Ni Nanowire Arrays
    YU Cui-Yan1,2, YU Yan-Long2, SUN Hong-Yu1, LI Wei1, XU Tao1, ZHANG Xiang-Yi1*
    2007, 28(12):  2239-2241.  doi:
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    Single-crystal Ni nanowire arrays were prepared by employing the porous AAO template by using the electrodeposition technique at a constant current of 2.0 mA/cm2. The morphology and microstructure of Ni nanowire arrays were studied by SEM, TEM and XRD techniques. The magnetic properties of the single-crystal Ni nanowire arrays were investigated by VSM. The results reveal that the single-crystal Ni nanowire arrays show a perpendicular magnetic anistory and have a preferential magnetic orientation along the wire axis. The magnetic properties of the single-crystal Ni nanowire arrays are better than those of polycrystal nanowire arrays.

    New 1D Ladder-Like Chain Polyoxometalate Consisting of the Paradodecatungstate Linked by Mn2+ Ions
    GAN Xiong1,2, ZHANG Zhi-Ming1, WANG En-Bo1*
    2007, 28(12):  2242-2245.  doi:
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    A new 1D ladder-like chain polyoxotungstate K6[Mn2(H2O)8(H2W12O42)]·14.5H2O(1) was synthesized in aqueous solution and characterized by elemental analysis, IR spectroscopy, TG analysis, UV, CV and single crystal X-ray diffraction. The interesting characteristics of compound 1 show that the paradodecatungstate [H2W12O42]10- anions are linked by Mn2+ ions forming a ladder-like one-dimensional chainlike structure, which is connected by K+ ions a 3D framework. The oxidation states of W and Mn sites in this compound are determined to be +6 and +2, respectively.
    Preparation and Optic Properties of Water-Soluble ZnO Quantum Dots
    ZHUANG Jia1*, CHI Yan-Hua2, LIU Meng2
    2007, 28(12):  2246-2251.  doi:
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    SiO2/ZnO water-soluble quantum dots were prepared by modification of (3-mercaptopropyl)tri-ethoxysilicane. The emission spectral peak of exciton fluorescence was raised by about 4 times in comparison with that of the quantum dots obtained by direct SiO2 deposit on ZnO without modification. The introduction of hydrosulfide group(HS—) on ZnO, renders the quantum dots good water solubility, unique fluorescent stability and anti-congregation even at higher NaCl concentration. The water soluble blue SiO2/ZnO quantum dots were also prepared by this method with some modification of the reaction conditions. The photogenic wavelength of this blue quantum dots was found to be 420 nm. The emission spectra were very symmetrical without obvious red tail. The full widths half maximum were only 46 nm.
    研究快报
    Synthesis and Structure of Manganese Zinc Phosphate-phosphite with Extra Large Twenty-membered Ring Channels
    YANG Yang, ZHAO Yong-Nan*, YU Jian-Guo
    2007, 28(12):  2252-2254.  doi:
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    A novel three-dimensional manganese zinc phosphatophosphite [H2CHBMA][Zn1.5Mn(HPO3)2(PO4)]·H2O(TJPU-3Mn) with extra-large twenty-membered ring channels was isolated by 1,3-cyclohexanebis(methylamine) as the template under hydrothermal conditions. Single crystal structure refinement reveals that TJPU-3Mn crystallizes in the monoclinic space group C2/c, with cell parameters, a=3.3929(7) nm, b=1.3045(3) nm, c=0.89713(18) nm, β=104.37(3)°, V=3.8465(13) nm3, Z=2. The connectivities of the ZnO4, MnO4, PO4 and HPO3 groups create a three-dimensional porous architecture with extra-large twenty-membered ring channels intersected by eight-membered rings. It is the first structure analogue to the famous aluminophsphate JDF-20. More interestingly, the diprotonated CHBMA cations in the channel are all in cis configuration, indicating the potential for separation and recognition of CHBMA isomers. Powder X-ray patterns reveal the structure of TJPU-3Mn sustains after the emission of water molecules obtained by calcining at 150 ℃ for 2 h.
    研究论文
    Heat-Induced Changes of Secondary Structures of BSA in D2O Studied by Infrared Spectroscopy and Window Factor Analysis
    YUAN Bo*, YAN Hui-Min
    2007, 28(12):  2255-2258.  doi:
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    Heat-induced changes of secondary structures of bovine serum albumin(BSA) in D2O was studied by using infrared spectroscopy and window factor analysis(WFA). The results obtained from the conventional spectral analysis methods and WFA indicate that conformational changes of BSA began at 56 ℃, while the drastic variations of secondary structures occurred in the temperature range of 68—82 ℃. Additionally, the temperature at which the variation of short-segment chains connecting α-helical segment took place is lower by round 10 ℃ than that of the other secondary structures. The present study reveals that WFA plays a key role in the analysis the temperature-dependent infrared spectra of protein in solution.
    Self-heating and Sensing Static Chip Polymerase Chain Reaction(PCR) of Transparent Electro-conductive Glass Substrate(ITO)
    WU Zhi-Yong*, TIAN Xiao-Xi, QU Bai-Yan, CHEN Kun, FANG Fang
    2007, 28(12):  2259-2263.  doi:
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    Static chip polymerase chain reaction(PCR) needs no mechanical parts, and is easy to be integrated with chip separation and detection system, thus has a wider application in analysis field and POCT(point of care test). Chip thermal-time program control is crucial in static chip PCR, normally this is achieved with the aid of micro-fabrication technique in preparing the heating and sensing elements on chip. In this article, a thermostat chip that is capable of self-heating and sensing automatically and programmatically was established for the first time with commercial indium-tin oxide(ITO) glass substrate without involving any micro-fabrication process. The transparent and elelctro-conductive layer was used both as heating and temperature sensing elements, and time delay due to separate sensor is minimized. Electrical contacts is reduced from two couples(one for heating and one for sensing) to only one for each thermostat chip unit. The system has a control stability of 0.2 ℃, a maximum temperature ramping rate above 20 ℃/s and a cooling rate 8 ℃/s with the aid of a cooling fan. Multiple open reaction reservoirs can be constructed directly on the chip surface, and static chip PCR of a λDNA fragment(c.a. 157 bp) is successfully demonstrated. In-situ real-time fluorescence monitoring of a dsDNA and SYBR Green Ⅰ mixture during the temperature cycling was also demonstrated by placing the chip on the sample stage of an inverted fluorescence microscope that equipped with a blue light emission diode(575 nm) and a photomultiplier tube.
    Degradation of Ginsenosides in Root of Panax ginseng C. A. Mey. by High-pressure Microwave-assisted Extraction
    WANG Yu-Tang, LI Xu-Wen, JIN Hai-Yan, YU Yong, YOU Jing-Yan, ZHANG Kun, DING Lan, ZHANG Han-Qi*
    2007, 28(12):  2264-2269.  doi:
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    During the process of high-pressure microwave extraction, the crude ginseosides in root of Panax ginseng C. A. Mey.(P. ginseng) can be degradated. Some glycosyls can partly be put off and the sub-ginseosides can be obtained. So the sub-ginseosides can be directly extracted from the root of P. ginseng. HPLC-ESI-MS was applied to determine the ginsenosides. The degradation conditions of crude ginseosides were examined and the degradation products of ginseoside Rg1, Re, Rb1, Rc, Rb2 and Rd were also studied. The results indicate that with the increase of the extraction pressure, the contents of the ginsenosides decrease and meanwhile the contents of some low polar sub-ginseosides increase. At the extraction pressure of 600 kPa and the extraction time of 10 min, the crude ginseosides in root of P. ginseng can be completely degradated. The content of sub-ginseosides Rg3 is the highest. The ginsenosides Rg3 can be found in the degradation products of ginseoside Rb1, Rc, Rb2 and Rd.
    Novel Fluorescent Probe for Lead Ion Detection Based on DNAzyme
    WANG Qing, YANG Xiao-Hai, WANG Ling, WANG Ke-Min*, ZHAO Xiang
    2007, 28(12):  2270-2273.  doi:
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    A novel fluorescent probe for Pb2+ was obtained, in which the quencher modified 17E DNAzyme and the fluorophore-modified substrate strand were connected through 6 adenine deoxynucleotides. Due to the intramolecular hybridization between 17E DNAzyme and the substrate strand, the quencher was closed to the fluorophore and it resulted in fluorescence quenching. In the presence of Pb2+, the substrate strand was cleaved under the catalysis of enzyme strand, and the fluorophore-modified fragment was released, which resulted in the increase of fluorescence. Pb2+ could be rapidly detected at room temperature based on this principle, and the limits of detection were 10 nmol/L. For divalent metal ions, such as Zn2+, Mn2+, Co2+, Cd2+, Cu2+, Mg2+ and Ni2+, only Zn2+, Mn2+ and Cd2+ showed a slight increase of fluorescence intensity while all the other metal ions gave approximately background intensity. It is demonstrated that the novel fluorescent probe has a good selectivity to Pb2+.
    Approaching Signal Amplification of Electrochemical Biosensor for Thrombin Based on Enrichment of Gold Nanoparticles Through Hybridization with Complementary Oligonucleotide
    ZHENG Jing1,2, FENG Wan-Juan1, CHENG Gui-Fang1, HUANG Cui-Hua1, LIN Li1, HE Pin-Gang1* , FANG Yu-Zhi1
    2007, 28(12):  2274-2279.  doi:
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    In this paper, a signal amplified electrochemical biosensor for thrombin based on the enrichment of the gold nanoparticles through the hybridization with the complememtary oligonucleotide was presented. Thrombin, as a typical protein model, has two combination sites with aptamers. In the experiment, aptamer Ⅰ was immobilized on magnetic nanoparticles for capturing thrombin, and aptamer Ⅱ was labeled with gold nanoparticle to offer an excellent electrochemical signal transduction. Through the specific recognition for thrombin, a sandwich format of magnetic nanoparticle/thrombin/gold nanoparticle was fabricated. And the signal amplification was further implemented by the enrichment of gold nanoparticles through the hybridization with the gold labeled complementary oligonucleotide,the resulting hybridization is capable of realizing more gold nanoparticle markers attaching to each target protein. A significant enhancement of the sensitivity was obtained for the detection of thrombin with the signal amplification. This new strategy allows the detection limit of the target protein down to 4.52×10-15 mol/L. The relative standard deviation of eight replicate determinations of 7.47×10-14 mol/L thrombin was 3.0%. The presence of other proteins such as BSA and lysozyme did not affect the detection of thrombin, which indicates that a high specificity of thrombin detection can be achieved.
    Spectroscopic Studies on the Interaction Between Rifabutin and Human Serum Albumin
    WANG Cong-Xia, YE Ling*, YAN Fang-Fei, WANG Nan, YU Pei-Lin
    2007, 28(12):  2280-2283.  doi:
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    The binding mechanism between Rifabutin(RB) and human serum albumin(HSA) was studied by fluorescence spectroscopy and CD. The results show that RB quenched the intrinsic fluorescence of HSA via a combination of static and dynamic quenching processes and hydrophobic interaction played a major role in stabilizing the RB-HSA complex. The binding constant Ka was calculated to be in the order of 106, indicating a strong interaction between RB and HSA. In addition, influences of metal ion(Cu2+, Zn2+, Mg2+ and Ca2+) on Ka were studied. Moreover, synchronous fluorescence spectroscopy and circular dichroism(CD)reveal the conformational change of HSA upon binding with RB.
    Identification and Mass Spectrometric Characterization of Isomeric Isoflavone Aglycones by ESI-IT-TOF Mass Spectrometry
    LI Hui1, WAN Le-Ren2, WANG Hong1, Hashi Yuki2*, CHEN Shi-Zhong1*
    2007, 28(12):  2284-2289.  doi:
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    A mass spectrometric method based on the combined with electrospray ionization/ion trap/time-of-flight(ESI-IT-TOF) mass spectrometer was used for systematic research of 7-methoxy-4'-hydroxy isoflavone and formononetin. MS5 spectra both in positive and negative ion modes with a high resolution were obtained. Different product ions were observed in positive ion mode, while almost the same product ions were observed in negative ion mode. With the high selectivity of parent ions and precise formulae of each fragment, fragmentation mechanisms were proposed with a high reliability. The established method could be used for the sensitive and rapid identification of isoflavonoids.
    Electrochemical Detection of Sequence Specific DNA Binding Protein with Gold Nanoparticle-catalized Ag Enhancement
    PAN Qin, XU Li-Jian, WANG Zhi-Fei, LU Zu-Hong*, HE Nong-Yue*
    2007, 28(12):  2290-2294.  doi:
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    The interactions between transcription factor and sequence specific DNAplay important roles in drug genome and transcription diagnosis. Gold nanoparticlesshow high sensitivity, stability and compatibility for biological molecules as electrochemical intercalators. NF-κB is a family of transcription factors that regulates a wide variety of biological processes such as inflammation, apoptosis, cell cycle control, cell migration and wide variety of cancers. There is no report of sequence specific DNA binding NF-κB detection by gold nanoparticle catalyzed Ag enhancement at the interface between electrodes and electrolyte solutions. Here unimolecular hairpin oligonucleotides were self-assembled onto Au electrode surface and elongation on solid phase was carried out to double strand oligonucleotides with transcription factor NF-κB binding site. The elongation of unimolecular hairpin oligonucleotides on Au electrodes was verified by incorporation of biotin labeled dUTP during the elongation followed by addition of gold nanoparticle labeled streptavidin and detection of anodic stripping voltammetry(ASV) signals of gold nanoparticle-catalyzed Ag deposition. Then gold nanoparticle-catalyzed Ag deposition was detected by ASV for NF-κB binding and the specificity of NF-κB binding and the detection limit were explored. It was resulted the detection low limit was as low as 0.1 pmol/L, which was five magnitude lower than the applied fluorescence method for DNA-protein interactions detection on the aldehyde-coated glass slides. It was indicated that this new method for sequence specific DNA binding protein detection showed pronounced specificity, sensitivity and could find application to transcription regulation research, open reading frame characterization and functional gene inspection.
    Determination of N—NO Bond Dissociation Energies of N-Nitrosoindoles and Their Radical Anions in Acetonitrile
    LI Xin, ZHU Xiao-Qing, WANG Xiao-Xiao, CHENG Jin-Pei*
    2007, 28(12):  2295-2298.  doi:
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    The heterolytic and homolytic N—NO bond dissociation energies of seven N-nitrosoindole derivatives were evaluated by using titration calorimetry and relative thermodynamic cycles. The energetic scales of the heterolytic and homolytic N—NO bond dissociation energies of N-nitrosoindoles cover the ranges from 206.1 to 246.2 kJ/mol and from 119.1 to 124.6 kJ/mol, respectively, which indicates that N-nitrosoindoles are much easier to release a NO radical(NO·) rather than a NO cation(NO+). The estimation of the heterolytic and homolytic(N—NO) bond dissociation energies of the N-nitrosoindoles radical anions gives the energetic ranges from 25.5 to 33.4 kJ/mol and from 5.0 to 40.5 kJ/mol for the(N—NO) bond homolysis and heterolysis, respectively, which means that N-nitrosoindole radical anions are unstable at room temperature.
    Separation of Caveolae and Atomic Force Microscopy Study of Them
    CHEN Ying-Ying, SUN Run-Guang*, WANG Bo, ZHANG Ming
    2007, 28(12):  2299-2302.  doi:
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    Caveolae were spherical, elliptical or flask-shaped invaginations(50—100 nm in diameter) on the surface of cell plasma membrane. They play important roles in many biological processes, such as endocytosis, pinocytosis, cholesterol transport, signal transduction, internalization of bacteria and viruses, and so on. In this research, caveolae were separated from rat lungs by floating plasma membrane treated with ultrasonic in OptiPrep gradient(a detergent-free method), and were observed by atomic force microscopy(AFM) under different conditions. By using this method, intact caveolae were isolated from plasma membrane, and the best AFM images of caveolae were obtained by diluting them 500 times with deionized water. So, a new method for separating caveolae rapidly and completely was established, and a new way to observe the structures of caveolae was set up.
    New Steroidal Saponin from Paris polyphylla Sm. var. yunnanensis(France.)Hand.-Mazz.
    XU Tun-Hai1, MA Xiao-Xia2, XU Ya-Juan2*, XIE Sheng-Xu2, ZHAO Hong-Feng2, SI Yun-Shan2, HAN Dong2, LI Yu1, NIU Jian-Zhao1, XU Dong-Ming2
    2007, 28(12):  2303-2306.  doi:
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    Traditional Chinese Medicine “zhonglou”(Paris polyphylla) is the important medicine used to treat traumatism. A new steroidal saponin, together with four known steroidal saponins, was isolated from the rhizoma of Paris polyphylla. The structure of the new steroidal saponin, named Paripolyside A was elucidated as 24-O-β-D-galactopylanosyl-(23S,24S)-spirosta-5, 25(27)-diene-1β,3β,23, 24-tetrol-1-O-β-D-xylopylanosyl(1→6)-β-D-glucopyranosyl(1→3)[α-L-rhamnopyranosyl(1→2)]-β-D-glucopyranoside mainly by using 1D, 2D NMR techniques, ESI-MS analysis as well as chemical methods.
    Enzymatic Resolution of (R,S)-2-Octanol by Ultrastable-Y Molecular Sieve Immobilized-lipase in Microaqueous Media
    DAI Da-Zhang*, XIA Li-Ming
    2007, 28(12):  2307-2310.  doi:
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    The resolution of (R,S)-2-octanol was performed in microaqueous media by P. expansum PED-03 lipase(PEL) immobilized onto Ultrastable-Y modified molecular sieve. It was found that conversion(c), enantiomeric excess(e.e.), and enantioselectivity(E) of the reaction catalyzed by PEL immobilized onto Ultrastable-Y modified molecular sieve were much higher, compared with free PEL and PEL immobilized by other carriers. Media type and water content played an important role in the resolution of (R,S)-2-octanol catalyzed by Ultrastable-Y modified molecular sieve immobilized-PEL, and the reaction conversion(c) reached 97.68% of the theoretical value and the enantiomeric excess(e.e.) reached 98.75% in n-hexane with 0.8% water at “memorial” pH =9.5 and 50 ℃ for 24 h. The modified Ultrastable-Y molecular sieve immobilized-PEL was a good biocatalyst with a fine enantioselectivity and stability, presenting a good promise in the enzymatic resolution of (R,S)-2-octanol.
    Synthesis of 3-Arylthiophenes with Luminescent Property via Suzuki Cross-coupling Reaction Catalyzed by Cyclopalladated Ferrocenylimine
    ZHANG Jin-Li1, WU Yang-Jie1*, LI Jing-Ya1, DU Chen-Xia1, ZHENG Ju-Mei1, THOMAS C. W. Mak2, SONG Mao-Ping1
    2007, 28(12):  2311-2315.  doi:
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    Aryl-substituted thiophenes are important fine chemicals and can constitute ubiquitous fragments of the active semiconducting layer in organic field effect transistors(OFETs). Among the variety of useful methods for the synthesis of these kinds of compounds, palladium-catalyzed Suzuki cross-coupling reaction received more researchers’ attentions. Cyclopalladated ferrocenylimines catalyzed Suzuki cross-coupling reaction of aryl iodides, bromides with 3-thienylboronic acid was carried out in DMF at 80 ℃ in the presence of K3PO4 and without the protection of inert gas. This method has the advantage of low loadings both of catalyst and 3-thienylboronic acid, simple and easy handling procedure. By using this method the synthesis of 3-arylthiophenes could be readily achieved. The emission and excitation spectra of compounds 3b, 3c, 3d confirmed that 3-arylsubstituted thiophenes were a kind of potential organic LEDs materials.
    Syntheses and Photo-electricity Properties of Star-shaped Organic Molecules Containing 1,3,4-Oxadizole and Arylamine Materials
    XIANG Neng-Jun1,2*, XU Yong1, LEUNG Louis M3, GONG Meng-Lian2
    2007, 28(12):  2316-2320.  doi:
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    Two fluorescent star-shaped molecules, based on a N core, containing an hole-transporting arylamine and an electron-transporting 1,3,4-oxadiazole units were synthesized via a facile multi-steps procedure with a high yield. The star-shaped compounds TTPAOPA and TpMOKPAOPA emit blue light with high fluorescence quantum yields in the 0.82—0.95 range which indicate that they are high efficient light-emitting materials. The HOMO values are -5.28 eV and 5.46 eV, respectively. Reversible anodic oxidation results suggest that the compounds are predominantly hole-transporting. All the results indicat that the synthesized compounds are potentially good candidates as bipolar(hole-transporting/electro-transporting)and emitting materials for fabrication of organic light-emitting diodes.
    Structure Change and Intermediate's Lifetime of Bacteriorhodopsin and Its Multipoint Mutants
    JIN Wei-Hua1, CAO Jun-Wei1*, WANG You-Liang1, XIONG Gui-Guang2, YAO Bao-Li3, LEI Ming3
    2007, 28(12):  2321-2326.  doi:
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    The site-specific residue replacements E194Q, I119T/T121S/A126T and I119T/T121S /A126T/E194Q were introduced into bop gene and expressed in halobacterium salinarium L33 with the vector pXL-NovR, respectively. The photoreaction of three mutants BRE194Q, BRI119T/T121S/A126T and BRI119T/T121S/A126T/E194Q(the quadruple mutant) of bacteriorhodopsin(BR) and WT-BR(wild type BR) was investigated in solution and in PVA films at pH=7.0 by UV-Vis absorption spectrum and Resonance Raman spectra. The lifetime of M intermediate of the three mutants in PVA films were recorded by employing photomicrography. In distilled water, the visible absorption maximum of BRI119T/T121S/A126T and BRI119T/T121S/A126T/E194Q mutants were blue shifted notably by 11 and 12 nm respectively and the BRE194Q's was weakly red shifted in comparison with WT-BR. In PVA film, BRI119T/T121S/A126T/E194Q mutant caused a blue shift of the visible absorption spectrum from 568 to 557 nm. The characteristic bands of Resonance Raman spectra of BRI119T/T121S/A126T/E194Q mutant were observed at 1334cm-1 of the L intermediate, 1200, 1328, 1530 and 1549 cm-1 of the N intermediate and 1567 and 1573 cm-1 of M intermediate in solution. However, the 1334 and 1549 cm-1 bands of the quadruple mutant disappeared and the intensity of 1187 cm-1 band decreased in PVA film. The lifetime of M intermediate of BRE194Q was less than 1.0 s by photomicrography. The lifetime of M intermediates of BRI119T/T121S/A126T and BRI119T/T121S/A126T/E194Q were 3.0 s and 2.0 s, respectively.
    研究快报
    Determination of NO Chemical Affinities of Benzyl Nitrite in Acetonitrile
    LI Xin, ZHU Xiao-Qing, CHENG Jin-Pei*
    2007, 28(12):  2327-2329.  doi:
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    There is an increasing interest for the study of NO affinity of organic nitrite, for the biological and physiological effects of organic nitrites seem to be due to their ability releasing NO. In this paper, NO chemical affinities of ten benzyl nitrites were determined respectively by titration calorimetry and from a thermodynamic cycle in acetonitrile solution. The results show that ΔHhet of O—NO in the O-nitroso compounds were substantially larger than the corresponding ΔHhomo of O—NO in the same compounds, suggesting that these O-nitroso compounds were much easier release NO radical by the O—NO bond homolytic cleavage. It is believed that the structural and energetic information disclosed in this work should be useful in understanding chemical and biological functions of organic nitrites.
    Selective Deprotection of N-Boc Catalyzed by Silica Gel
    ZHANG Min-Jie1,2, YUAN Xiu-Hua1, MA Li1, ZHAO Jian-Ying1, GAO Lian-Xun1*
    2007, 28(12):  2330-2332.  doi:
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    As an important protective group of amines and amino acids, tert-butoxycarbonyl(Boc) group was extensively used in organic synthesis. Though many mild and selective reagents could be used, there is still a need for the development of a more simple and convenient method for deprotection. In this paper, a new method for the deprotection of N-Boc group with silica gel in refluxing toluene was reported. The reactions were mostly achieved in 5 h with high yields(75%—98%). N-Boc protected indoline and benzylamine, which are not deprotected with other mild method, could be deprotected with our method in good yields(89% and 95%, respectively). Additionally the deprotection of other carbamates such as Cbz, Fmoc and ethyl carbamate wasn’t observed under same conditions.
    研究论文
    Synthesis of High-specific-surface-area Solid Strong Base MgO with Pinewood as Exotemplate
    SUN Rui-Qin, ZHOU Xu, SUN Lin-Bing, WU Hao, CHUN Yuan*, XU Qin-Hua
    2007, 28(12):  2333-2337.  doi:
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    In this paper, a series of solid base MgO were synthesized via an exotemplating pathway with pinewood as the template and magnesium acetate as MgO precursor, and were characterized by XRD, SEM, adsorption of n-hexane or nitrogen, Hammett indicator, ICP, IR and TG-DSC techniques. It was found that these as-prepared MgO materials replicated the biomorph of pinewood, and their frameworks were constructed by plenty of claviform nanoparticles with a similar sectional area, which were different from those of MgO prepared by directly thermal decomposition of MgO precursor. The use of pinewood template was beneficial to the formation of the smaller crystalline size and higher specific surface area. These biomorphic MgO materials exhibit a strong basicity, and can be used as effective basic catalysts or supports.
    Inhibition Effect of δ-MnO2 on TiO2 Photocatalytic Degradation of Methyl Orange
    LI Shun-Jun1, MA Zi-Chuan1,2*, DING Ke-Qiang1, LIU Jing-Ze2*
    2007, 28(12):  2338-2342.  doi:
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    The influences of δ-MnO2 particles on the photocatalytic activity of P-25 TiO2 were investigated with kinetical method through the photocatalytic degradation of methyl orange. The TiO2 photocatalyst, before and after being contaminated by δ-MnO2, was characterized with UV-visible diffuse reflectance spectroscopy(UV-Vis DRS) and photoluminescence(PL). The dynamics results show the distinct existence of poisoning effect of δ-MnO2 on TiO2 photocatalysis at different initial pH values. The higher the concentration of the δ-MnO2, the more evident the poisoning effect. The characterizations indicate that the absorption band edge of TiO2 is blue-shifted and the intensity is decreased, and the intensity of PL signals of TiO2 is suppressed due to the contact between δ-MnO2 and TiO2. Therefore, the presence of δ-MnO2 increases the band gap and causes the decrease of UV absorption of TiO2, and δ-MnO2 can also act as a recombination centers of photoinduced electron-hole. The effects of δ-MnO2 particles in environment on the stability of TiO2 photocatalyst were revealed.
    Thermokinetics Study on the Deintercalation Reaction of Intercalating Composite Kaolinite/Dimethyl Sulphoxide
    QIN Fang-Fang1, HE Ming-Zhong1*, CUI Jing-Wei2, CHEN Qiang3
    2007, 28(12):  2343-2348.  doi:
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    The de-intercalation processes occurring in the solid state Kaolinite/Dimethyl sulphoxide were stu-died by using TG and XRD techniques, and a new method of how to calculate the kinetic triplet was proposed on the thermokinetics study: Firstly, the activation energy Ea is calculated by interative procedure; secondly, the optimized methanism and the corresponding function G(α), f(α) is derived from the regression of Malek method; lastly, the pre-exponential factor A is estimated by multiple rates-isotemperature method. The apparent activation energy Ea of the decomposition of Kaolinite/Dimethyl sulphoxide is about 86.65 kJ/mol, and the pre-exponential factor A is 1.6050×108—3.6151×108 s-1, the optimized methanism is nth-order chemical reaction, the corresponding functions are G(α)=[1-(1-α)1-n]/(1-n) and f(α)=(1-α)n. But the value of n has a relationship with the heating rate to a certain extent: when heating rate is rather quick(30 ℃/min)or rather slow(5 ℃/min), n is equal to 1.5, but when heating rate is between 7 and 25 ℃/min, n is equal to 1.6.

    Successive Preparation of High Blue Fluorescence of Decorated Nano Zinc Oxide Ethanol Sol by Pulsed Laser Ablation
    YU Hai-Li, ZHANG Wen-Gong*, HUANG Xiu-Xiu, LIN Feng-Long
    2007, 28(12):  2349-2354.  doi:
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    Decorated nano-ZnO ethanol sols which were modified in situ were successively produced by pulsed laser ablation at the interface of ZnO target submerged in the flowing liquid which contained modification agents. It is found that ZnO ethanol sol decorated by Hsal radiates intense blue light under ultraviolet radiation and has a broad emission band centered at 440 nm in the emission fluorescence spectrum. The emission intensity in 440 nm is as high as 1.12×105. We studied some factors including different modification agents and their added methods, concentration of Hsal(salicylic acid), flowing liquid velocity, aging time after preparation which have effect on luminescence characteristics of sols. The results shows that the decorated nano-ZnO ethanol sol with best fluorescent characteristics can be obtained in following conditions: ethanol solution of Hsal as flowing liquid, concentration of Hsal is 4.2×10-3 mol/L, flowing liquid velocity is 0.025 mL/s and proper aging time after preparation the ZnO ethanol sol. TEM results show that the diameter of nano-ZnO particles is about 15—30 nm. The study presents a convenient method to obtain the decorated nano-zinc oxide organic sol of high blue luminescence.
    Study of Self-assembled Membrane Structure of Binuclear Cobalt Phthalocyaninehexasulfonate by SERS
    AN Jing, JIA Hui-Ying, ZHAO Bing, YANG Guang-Di, XU Wei-Qing*
    2007, 28(12):  2355-2358.  doi:
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    We selected a Bi-CoPc(binuclear cobalt phthalocyaninehexasulfonate) and 4MPY(4-mercaptopyridine) as the building units. The ordered self-assembly membrane(SAM) of Bi-CoPc was constructed with 4MPY as an axial ligand link via self-assembly method. The structure and orientation of the SAMs were characterized by UV-Vis spectrum, Raman spectrum and SERS spectrum. Through studying the change of SERS spectrum of SAMs, self-assembly mechanism is discussed and the structure of self-assembled membrane is supposed rationally. The results reveal that 4MPY is assembled onto the silver surface, and ligated to Co via 4-position nitrogen along its axial direction. In the SAMs, the Bi-CoPc molecules are arranged slantwise to the substrate of the self-assembled membrane.
    Charge Transport and the Relationship Between Performance and Light Intensity of the Solar Cell Based on the Blend of MEH-PPV and PCBM
    YU Huang-Zhong1,2*, PENG Jun-Biao2
    2007, 28(12):  2359-2363.  doi:
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    The highly efficient solar cells based on the blend of MEH-PPV{poly[2-methoxy-5-(2'-ethylhexoxy)]-1,4-phenylene vinylene} as a donor and PCBM[1-(3-methoxycarbonyl)-propyl-1-1-phenyl-(6,6)C61] as an acceptor were fabricated. We obtained an open circuit voltage of 0.8 V, short circuit current density of 5.06 mA/cm2 and fill factor of 48.1% under 100 mA/cm2 air-mass 1.5 solar simulator illumination, yielding a 1.93% power conversion efficiency. There was not chemistry reaction between MEH-PPV and PCBM from their UV-Vis chart. The intense PL of MEH-PPV was, however, almost completely quenched, implying the excitons are effectively separated on the interface of donor and acceptor and transported in bicontinuous path. We alse analyzed physical meaning of the I-V curve chart under illumination and dark condition, discussed the charge transport between MEH-PPV and PCBM, and studied the diversification of solar cells performance at different light intensity. With the increase of incident light intensity, the short circuit current density of the solar cells enhanced, open circuit voltage increased slowly, the parallel resistance and the fill factor descended, series resistance did not change distinctly.
    Electrodeposition of CdS Nanoparticles on ITO/TiO2 Surface and the Photoelectric Performance of Their Composite Thin Films
    CHI Yu-Juan1, FU Hong-Gang1*, SHI Ke-Ying2, QI Le-Hui2, ZHANG Heng-Bin2, YU Hai-Tao2
    2007, 28(12):  2364-2368.  doi:
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    ITO/TiO2/CdS composite thin films were successfully prepared by electrodeposition of CdS nanoparticles on ITO/TiO2. The XRD and SEM results indicate that the CdS particles are hexagonal phase and the particle with cauliflower-like cluster distribute very uniformly in size. The growth of CdS nanoparticles can be effectively controlled by adjusting the electrodeposition potential and time. With the fall of potential and the decrease of time, the particle sizes decrease. The UV-Vis spectra indicate that the nanoparticles prepared under the different conditions have a very obvious size quantization effect. Furthermore, the electrodeposition conditions have very obvious effects on the photoelectronic performance of the obtained ITO/TiO2/CdS films.
    Two-photon Absorption and Optical Power Limiting Properties of Multibranch 1,3,4-Oxadiazole Derivatives
    QIAN Ying1*, HUANG Wei2, LU Zhi-Feng1, ZHU Xiao-Qin1, MENG Kang1, L Chang-Gui2, CUI Yi-Ping2
    2007, 28(12):  2369-2372.  doi:
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    TPA properties of carbozole-core and triphenylamine-core multi-branched 1,3,4-oxadiazole derivatives were measured with nonlinear transmission method. Single-photon excited fluorescence and two-photon excited fluorescence of chromophores were experimentally studied. When pumped with 800 nm laser irradiation, 9-ethyl-3,6-bis(2-{4-[5-(4-tert-butyl-phenyl)-[1,3,4]oxadiazol-2-yl]-phenyl}-vinyl)-carbazole(3) and tris[4-(2-{4-[5-(4-tert-butyl-phenyl)-[1,3,4]oxadiazol-2-yl]-phenyl}-vinyl)-phenyl]-amine(4) show strong two-photon excited blue and yellow green fluorescence at 485 nm and 547 nm respectively. These multibranched chromophores showed a large TPA cross-section(values of >104 GM can be achieved) and strong optical power limiting properties. The cooperative enhancement of TPA in these multi-branched structures was observed. This enhancement is partly attributed to the electronic coupling between the branches. The electronic push-pull structures in the repeated unit and their cooperative effect increase the TPA properties of multi-branched molecules.

    Preparation and Properties of Gel Polymer Electrolyte Used for Lithium Ion Batteries
    WANG Cun-Guo*, HE Li-Xia, DONG Xian-Guo, WANG Yi-Zhen, ZHAO Shu-Gao, SUN Lin, LIN Lin, XIAO Hong-Jie
    2007, 28(12):  2373-2376.  doi:
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    As the novel polymer electrolyte membrane, crosslinked P(AN-MA-IALi) was synthesized with monormers such as acrylonictrile(AN), methyl acrylate(MA) and itaconic acid lithium(IALi) via solution co-polymerization method. The molecular structure was characterized by means of FTIR, DSC and SEM. The electrochemical performance of polymer electrolyte membrane was studied by AC impedance. The results show that the conductivity of crosslinked P(AN-MA-IALi) based gel polymer electrolyte membrane could get to 10-5—10-4 S/cm measured at room temperature. The highest conductivity was 1.89×10-4 S/cm when the mass fraction of IALi was 3%.
    Theoretical Studies on Electronic Structures and Spectroscopic Properties of [Ru(Htcterpy)X3]3-[X=NCS, CN, Cl]
    LI Ming-Xia1,2, ZHOU Xin1, PAN Qing-Jiang2, ZHANG Hong-Xing1*, FU Hong-Gang2, SUN Chia-Chung1
    2007, 28(12):  2377-2380.  doi:
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    The ground-structures of [Ru(Htcterpy)X3]3-[X=NCS(1), CN(2), Cl(3), tcterpy=4,4',4"-tricarboxy-2,2:6',2"-terpyridine,] are optimized by DFT method(B3LYP). The calculated geometry parameters are in agreement with the experimental values. Absorption spectra in gas phase and in solutions(ethanol and water) are predicted at the TD-DFT/B3LYP level. The solvent effects are seriously considered by using the conductor-like polarizable continuum model(CPCM). For complexes 1—3, in gas phase and solution, the low-energy absorptions have a mixed MLCT/LLCT character, whereas the high-energy absorption are attributed to the intra-ligand π→π* charge transfer transitions. Our calculations reveal the blue-shift of the absorption spectra in solution with respect to those in gas phase, agreeing with experimental observations.
    Inelastic Tunneling Spectroscopy and Electron-Vibrational Coupling of Molecular Junctions
    YAN Liu-Ming1*, JI Xiao-Bo1,2, ZHU Su-Hua1,2, LU Wen-Cong1
    2007, 28(12):  2381-2384.  doi:
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    On the basis of the nonequilibrium Green's function theory and perturbation theory, an IETS formalism is developed. In the formalism, the nonequilibrium Green's function of a molecular junction is separated into contributions from the elastic and inelastic electron tunneling, respectively. And IETS is directly related to the electron-vibrational coupling constant. The formalism provides insights into the mechanism of active vibrational modes for IETS. By applying the Gaussian 03 and DUSHIN programs to our formalism, the IETS of molecular junctions of oligo(phenylene vinylene) and oligo(phenylene ethynylene) are calculated, and good agreement between the calculation results and experimental measurements is observed.
    Theoretical Studies on Excited State Proton Transfer Tautomerism Reaction and Spectroscopic Properties of 6-methyl-4-hydroxy Pyrimidine Monomers and Dimers
    ZHOU Zi-Yan1,2,3*, ZHAO Ji-Yang2, LIU Min2 , SU Zhong-Min2,3, XIE Yu-Zhong2, WU Xue2
    2007, 28(12):  2385-2389.  doi:
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    The excited-state intramolecular proton transfer tautomerism reaction of 6-methyl-4-hydroxy pyri-midine monomers and dimmers was investigated by the ab initio method with the self-consistent reaction field(SCRF) with Tomas's polarized continuum mode(PCM) and CIS theories at HF level on the basis of 6-311+G* and 6-31G basis set. By studying the potential energy surface, it was found that the monomer's ground-state proton transfer process together with the excited-state proton transfer process is a molecular system of four energy level, but dimmers were not, which can be used to explain the fact that UV-visible absorption and fluorescence spectra of monomer and dimers all corresponded to quinoid. The UV-visible absorption and fluorescence spectra of 6-methyl-4- hydroxy pyrimidine monomers and dimers under a solvent effect condition were also investigated with hybrid time-dependent density functional theory(TD-DFT) at MPW1PW91 basis set.
    研究快报
    Electrochemical Characteristics of Trioxane
    TIAN Tian1,2, LIU Chang-Peng1, LIAO Jian-Hui1, XING Wei1*, LU Tian-Hong1
    2007, 28(12):  2390-2392.  doi:
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    In the present communication, the electrooxidation of trioxane(1,3,5-trioxane) was studied as a new fuel for direct-oxidation-type fuel cells. Direct-oxidation-type fuel cells have attracted much attention in recent years for the potential application as portable power sources; it can convert energy directly to electrical energy with high efficiency and low emission of pollution. Trioxane is a solid and favors the logistics of safe transportation as a fuel.The electro-oxidation and electro-sorption characteristics of this fuel at platinum electrode were investigated with electrochemical methods. The cyclic voltammetric result suggests that the electro-oxidation processes occur via chemisorption steps followed by surface reactions of adsorbed intermediates. The rate of electro-oxidation changed with the change of concentration of trioxane, acidity and temperature. The electro-oxidation of trioxane is carried out by an acid-catalyzed hydrolysis step in sulfuric acid solutions.
    研究论文
    Synthesis of Poly(methyl methacrylate)-block-Poly[methyl(3,3,3-trifluoropropyl)siloxane] Diblock Copolymers via Anionic Polymerization Method
    YI Ling-Min, ZHAN Xiao-Li*, CHEN Feng-Qiu, JIANG Bo, CHEN Bi
    2007, 28(12):  2393-2397.  doi:
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    The anionic block copolymerization of methyl methacrylate(MMA) and 1,3,5-trimethyl-1,3,5-tris(3',3',3'-trifluoropropyl)cyclotrisiloxane (F3) was carried out with an acetal-functionalized alkyllithium as the initiator, and poly(methyl methacrylate)-b-poly[methyl(3,3,3-trifluoropropyl)siloxane](PMMA-b-PMTFPS) diblock copolymers with a narrow molecular weight distribution were synthesized. The block copolymers were characterized by gel permeation chromatography(GPC), proton nuclear magnetic resonance spectroscopy (1H NMR), Fourier transform infrared spectroscopy(FTIR) and differential scanning calorimetry(DSC). The results show that the selection of the concentration of F3 was very important for obtaining PMMA-b-PMTFPS diblock copolymers with high yield when the terminal lithium alkoxide functional poly(methyl methacrylate)(PMMA-OLi) was served as the macroinitiator of anionic ring-opening polymerization(ROP) of F3. Additionally, DSC results show that the glass transition behaviors of PMMA-b-PMTFPS diblock copolymers were dependent on the content of PMTFPS blocks. The glass transition temperature of PMTFPS blocks is about -69—-70 ℃, and the glass transition temperature of PMMA blocks is about 128—130 ℃.
    Synthesis and Characterization of Novel PEEKs with Pendant Long Chains and Relationship Between Their Structures and Properties
    BI Da-Wu, NA Hui*
    2007, 28(12):  2398-2402.  doi:
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    Two novel types of Bisphenol monomers with different pendant long chains are synthesized and characterized by element analysis and nuclear magnetic resonance(NMR). Poly(ether ether ketone)s with different pendant long chains are prepared via aromatic nucleophilic substitution reaction from 1,4-bis(4-fluorobenzoye) benzene and these synthesized bisphenol monomers. FTIR is used to characterize the structure of PEEKs. The thermal properties of the polymers are investigated by DSC and TGA. Due to the existence of pendant long chain in PEEKs, the Tg and the temperature of 5% mass loss decrease. The solubility of the polymer is improved. From these results, the relationships between their structures and properties are well established.
    Preparation of Hyperbranched Polycarbosilazane via Ultraviolet Initiated Hydrosilylation
    ZHANG Guo-Bin, FAN Xiao-Dong*, KONG Jie, LIU Yu-Yang
    2007, 28(12):  2403-2407.  doi:
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    Hyperbranched polycarbosilazane P1 was successfully prepared from AB4 type monomer bis(N,N-diallylamino)methylsilane via fast hydrosilylation initiated by ultraviolet(UV) irradiation, with bis(acetylacetonato)platinum(Ⅱ) as the catalyst. For comparison, hyperbranched polycarbosilazane P2 was also prepared with the same monomer via heating-initiated polymerization at 80 ℃ with Karstedt's catalyst. The structures of the resulting polymers were well characterized by FTIR, 1H NMR, 13C NMR, 29Si NMR and size exclusion chromatography/multi-angle laser light scattering(SEC/MALLS) technology. By IR monitoring, it was found that polyhydrosilylation initiated by UV irradiation was much faster than that initiated by heating. NMR analyses confirmed that the resulting polymer possessed a hyperbranched architecture, indicating that α-hydrosilylation may mainly occur during UV-initiated polymerization. Degree of branching(DB) and average number of branches(ANB) of P1 were determined via 29Si NMR and were found to be 0.46 and 0.53, which were close to the theoretical values, respectively. And the weight average molecular weight, polydispersity index and exponent for Mark-Houwink equation of P1 were determined to be 12500 g/mol, 2.1 and 0.44, respectively, which were similar to those of P2.
    Preparation and Properties of Macromolecule Phytic Acid-Polysilsesquioxane
    YOU Bo*, XING Wen-Tao, WU Li-Min
    2007, 28(12):  2408-2412.  doi:
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    The high-molecular-weight phytic acid-polysilsesquioxane was successfully synthesized via sol-gel process by using silylated phytic acid reacting with MTES and TEOS without any low molecular acid, and the molecular weight of phytic acid-polysilsesquioxanes was more than 50000. Phytic acid served not only as catalysts but also reactant and chelating agent, which was in-situ incorporated with polysilsesquioxane chain uniformly. GPC, 13C NMR, 29Si NMR, XPS, Raman spectrum, SEM and electro-chemical techniques were used to investigate the correlation between the microstructure and property of PAP, TAP and HCP. PAP could form a compacting protective film because of strong chemical interaction between metal substrate and phytic acid-polysilsesquioxane, which had a significantly better corrosion resistance compared to tannin-catalyzed polysilsesquioxane and HCl-catalyzed polysilsesquioxane.
    Effect of Difference of Dielectric Constants Between Polyvinylidene Fluoride and Diluents on the Morphology of Polyvinylidene Fluoride Memranes Prepared by Thermally Induced Phase Separation
    YANG Jian1,2, ZHAO Wen-Ming1, WANG Xiao-Lin1*
    2007, 28(12):  2413-2417.  doi:
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    The effect of difference of dielectric constants between polyvinylidene fluoride(PVDF) and diluents on morphology of PVDF membranes prepared by thermally induced phase separation(TIPS) was studied. 1,4-Butyrrolactone, dimethyl phthalate, methyl salicylate, glycerol triacetate, carbitol acetate and di-n-butyl phthalate were selected as the diluents, respectively. The results show that the difference in dielectric constants between PVDF and diluents have a certain relationship with the morphology of membrane. The dielectric constant is one of important parameters of interaction among molecules. When the dielectric constant of PVDF is larger than that of the diluent, the attractive interaction among PVDF molecules lead to the aggregation of PVDF and crystallization. The incompact particle structure formed. When PVDF and diluents have a similar dielectric constant, attraction and repulsion exist in the equilibrium. The channel-like structure is formed under the condition of quenching. If the dielectric constant of PVDF is smaller than that of diluent, PVDF molecules crystallize difficultly in the diluent due to the repulsive interaction.
    Ring-open Polymerization of ε-Caprolactone Catalyzed by Substituted Indenyl Complexes
    QI Min-Hua1,2*, SHEN Qi2, SHEN Zhi-Quan3
    2007, 28(12):  2418-2421.  doi:
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    The substituted indenyl lanthanide(Ⅱ) complex (C5H9C9H6)2Yb(THF)2 applied to catalyzing the polymerization of ε-caprolactone was investigated. The results indicate that the complex (C5H9C9H6)2·Yb(THF)2 as single component catalyst showed a high activity, the conversion of the polymerization and the number-average molecular weight of the polymers were affected by temperature and time of polymerization, and using dose of the catalyst in polymerization process. The number-average molecular weight and molecular weight distribution of the polymer were not sensitive to temperature. But the conversion increased to increasing the polymerization temperature; molecular weight distribution of PCL gained was narrow. Other modified substituted indenyl lanthanide(Ⅱ) complexes also showed a good catalytic activity. The order of catalytic activity of the substituted indenyl lanthanide(Ⅱ) complexes was as follows: (1-C2H5C9H6)2Sm(THF)2>(1-C5H9C9H6)2Sm(THF)>KSm(1-C5H9C9H6)3(THF)3>(1-PhCH2C9H6)2Sm(THF)2>(1-C5H9C9H6)2Yb(THF)2. The number-average molecular weight and molecular weight distribution of PCL was measured by GPC.
    Preparation and Pervaporation Properties of Blend Membranes of Poly-acrylamide/montmorillonite Nano-composite and Poly(vinyl alcohol)
    DONG Yong-Quan1,2, ZHANG Lin1*, HOU Tong-Gang1, CHEN Huan-Lin1, GAO Cong-Jie1,3
    2007, 28(12):  2422-2426.  doi:
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    Polyacrylamide(PAM)/montmorillonite(MMT) nano-composite was prepared by in-situ polymerization. Morphology and dispersion of MMT within PAM were investigated by means of TEM. The results show that MMT lamellas exfoliate from PAM matrix. Blend membranes were prepared by ultrasonic dispersion of PAM/MMT and poly(vinyl alcohol)(PVA) solution. The swelling properties of blend membranes in isopropanol aqueous solution and effect of blend ratio, MMT content on separation properties were investigated. The results show that the separation properties of membrane could be improved greatly by adding proper content of MMT nano-particle in PVA.