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Synthesis of a novel centipede-like copolymer of styrene and methyl methacrylate

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Science china chemistry 2007年第2期50卷 253-257页

作者： LI AiXiang1 & LU ZaiJun2 1 school of Material Science and engineering,Shandong university of Technology,Zibo 255049,china 2 school of chemistry and chemical engineering,Shandong university,Jinan 250100,china 1. school of Material Science and engineering Shandong University of Technology Zibo 255049 China 2. school of chemistry and chemical engineering Shandong University Jinan 250100 China

A well-defined,A2B-type,centipede-like copolymer of styrene and methyl methacrylate(PS-PS-PMMA) was synthesized by the combination of living anionic polymerization and atom transfer radical polym-erization(ATRP) . The synthetic approach involves the coupling reaction of polystyrene(PS) backbone bearing 1,1-diphenylethene(DPE) pendant groups,produced by ATRP and Wittig reaction,with living polystyryllithium(PSLi) ,and subsequent polymerization of the resulting 1,1-diphenylmethyl anions with methy methacrylate. The centipede-like copolymer was characterized by 1H NMR,IR,SEC,SLS,and DSC measurements.

关键词： architecture atom transfer radical polymerization centipede-like copolymer coupling reaction living anionic polymerization

Effect of Excipients on Stability and Structure of rhCuZn-SOD Encapsulated in PLGA Microspheres

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chemical Research in Chinese Universities 2004年第3期20卷 323-327页

作者： LIU Ling 1,2 ,GE Yu 1 and YUAN Qin-sheng 1 1. State Key Laboratory of Bioreactor engineering and Institute of Biochemistry,East china university of Science and Technology,Shanghai 200237,P. R. china 2. Public Health school,nanjing Medical university,nanjing 210029,P. R. china E china Univ Sci & Technol State Key Lab Bioreactor Engn Shanghai 200237 Peoples R China E china Univ Sci & Technol Inst Biochem Shanghai 200237 Peoples R China nanjing Med Univ Sch Publ Hlth Nanjing 210029 Peoples R China

When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.

关键词： Poly( DL -lactide-co-glycolide)(PLGA) microsphere Recombinant human Cu Zn-superoxide dismutase(rhCu Zn-SOD) Fourier transform infrared(FTIR) spectroscopy Protein stability Excipient

Kinetic theory of self-condensing vinyl polymerization

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Science china chemistry 2010年第12期53卷 2429-2439页

作者： ZHOU ZhiPing 1 & YAN DeYue 2 1 school of Materials Science and engineering,Jiangsu university,Zhenjiang 212013,china 2 school of chemistry and chemical engineering,Shanghai Jiao Tong university,Shanghai 200240,china 1. school of Materials Science and engineering Jiangsu University Zhenjiang 212013 China2. School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China

This review introduces the kinetic theory of self-condensing vinyl polymerization (SCVP),including the SCVP of AB inimers,the SCVP with non-equal reactivity between A and B groups,the SCVP in the presence of a small amount of multifunctional initiators,also the SCVP of both inimers and *** analytical expressions of various molecular parameters for the resulting hyperbranched polymers,such as the molecular size distribution function,the average molecular weight,the polydispersity index and the degree of branching,are reviewed systematically.

关键词： kinetic theory self-condensing vinyl polymerization (SCVP) hyperbranched polymers

A New Thionine Modified Electrode by Anchorage to Bi-(2-aminoethyl)-aminodithiocarboxyl Acid Self-assembled Monolayers through Coordination with Cu^(2+#)

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Chinese chemical Letters 1997年第11期8卷 993-996页

作者： Jing Juan XU Hong Yuan CHEN Rui Qun FANG (Department of chemistry, the State Key Laboratory of Coordination chemistry, nanjing university, nanjing, 210093) Department of chemistry State Key Lab. of Coord. Chemistry Nanjing University Nanjing 210093 China

A new method for preparing chemically modified gold electrode by anchoring thionine to self-assembled bi - (2 -aminoethyl) -aminodithiocarboxyl acid(BANTC) monolayers through coordination with Cu2+ is described. This thionine modified electrode exhibits two-new redox *** protons were involved in the electrochemical process undergone by the couple I in the pH range of 5.0-10.0. The apparent surface electron transfer rate constant is about 0.050s-1.

关键词： aminodithiocarboxyl Acid Self-assembled Monolayers through Coordination with Cu A New Thionine Modified Electrode by Anchorage to Bi aminoethyl

Preparation,crystal structure and quantum chemical investigation of[Li(NTO) (H_2O)_2]

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Chinese Science Bulletin 1999年第3期44卷 214-218页

作者： SONG Jirong , CHEN Zhaoxu , XIAO Heming , HU Rongzu and LI Fuping Department of chemical engineering, Northwest university, Xi’ an 710069, china Department of chemistry, nanjing university of Science and Technology, nanjing 210094, china Xi’an Modern chemistry Research Institute, Xi’ an 710065, china Department of chemical engineering Northwest University Xi’an China Department of chemistry Nanjing University of Science and Technology Nanjing China Xi’an Modern chemistry Research Institute Xi’an China

[Li（NTO）(H2O2]was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one （NTO） and lithium hydroxide. The crystal structure of [Li（NTO）（H2O）2] was determined by single crystal diffraction analysis. The crystal is monoclinic, space group P21/n with crystal parameters of α =0.7420（2） nm, b=0.344 9（1） nm, c=2.490 6（3） nm,β=94.89（1）°, Z=4, Dc=1.799 ***-3, V=0.635 nm3,μ= 1.591 cm-1, F（000） = 392. The final R is 0.051. The MNDO MO calculation shows that the coordinate bonds of title compound possess certain extent of covalent character. O2 atom of NTO anion is bonded to Li atom; the nitro group will be lost first when NTO is decomposed.

关键词： NTO lithium coordination crystal structure MNDO MO method.

A NOVEL METHOD OF SECONDARY SYNTHESIS OF FeY ZEOLITE

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Chinese chemical Letters 1995年第10期6卷 911-914页

作者： Ai Min ZHANG Shu Lin BAO Qin Hua XU (Department of chemistry, nanjing university, nanjing, 210093) nanjing Univ Dept Chem Nanjing 210093 Peoples R China

FeY zeolites were prepared by three different secondary synthetic methods. Samples were characterized with XRD, IR, ESR, MBS and XPS techniques. The results showed that more iron ions were inserted into the framework of zeolite when the sample was pretreated with (NH4)(2)SiF6 aqueous solution. The structure of such zeolites has obviously changed due to the iron ions inserted into the framework.

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Influences of low-Ti substitution for La and Mg on the electrochemical and kinetic characteristics of AB_3-type hydrogen storage alloy electrodes

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Science china(Technological Sciences) 2010年第1期53卷 242-247页

作者： DONG ZhenWei1,2,WU YaoMing1,MA LiQun2,SHEN XiaoDong2 & WANG LiMin1 1 State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied chemistry,Chinese Academy of Sciences,C hangchun 130022,china 2 College of Material Science and engineering,nanjing university of Technology,nanjing 210009,china 1. State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The(La0.67Mg0.33)1-xTixNi2.75Co0.25(x = 0,0.05,0.10,0.15 and 0.20,at%) alloys were synthesized by arc melting and subsequent heat solid-liquid diffusing *** structure,electrochemical properties and kinetic characteristics of the alloys were investigated *** results showed that all the alloys mainly consisted of the(La,Mg)Ni3,LaNi5 phases,and the lattice parameters and the cell volumes of the(La,Mg)Ni3 and LaNi5 phases decreased with increasing Ti *** alloy electrodes could be activated to reach their maximum discharge capacity within five *** cycle life after 100 charge/discharge cycles(C100/Cmax) and the high-rate dischargeability at a discharge current density of 1200 mA/g first increased and then *** the results showed that low-Ti content in AB3-type hydrogen storage alloys was beneficial to improvements of the overall electrochemical properties,and the optimum overall electrochemical performance of the alloy electrodes was obtained when x = 0.05.

关键词： AB3-type alloy metal hydride electrode microstructure electrochemical property kinetic characteristic

Structure　of　Activity　Sites　in　Perovskite－type　Complexs　Oxides　LaMnO_3＋λ　for　Total　Oxidation　of　Methane

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Chinese chemical Letters 1996年第10期7卷 960-961页

作者： Zi Yi ZHONG Jian GONG Qi Jie YAN Xian Cai FU(Department of chemistry, Hunan Normal university, Changsha, 410081)(Department of chemistry, nanjing university, nanjing, 210093) Department of chemistry Hunan Normal University Changsha 410081 Department of chemistry Nanjing University Nanjing 210093

Nanometer oxide LaMnO3+λ and its counterparts with large particle size were comparatively studied for total oxidation of methane. XPS, TPR and nonstoichiometric oxygen (λ)analysis results identify that the nanometer chide contains more high valence cations, to which the adjacent lattice oxygen are responsible for total oxidation of methane at low temperature.

关键词： Activity Sites Structure Perovskite Complexs type

Infrared multiphoton dissociation of aceticanhydride:experimental study

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Chinese Journal of chemistry 1990年第4期8卷 306-312页

作者： XIANG, Tian-Xiang chemical Physics Laboratory, Department of chemistry, university of nanjing, nanjing 210008 chemical Physics Laboratory Department of Chemistry University of Nanjing Nanjing 210008

The infrared multi-photon dissociation (IRMPD) of acetic anhydride to generate state- selected CH_2 has been investigated by using time and wavelength resolved fluorescence techniques. It has been observed that the generation of the nascent ground state CH_2 (a^1A_1) is delayed by about 0.6 μs relative to the onset time of the excited CH_2(b^1B_1). The relative population of the ground and excited state CH_2 and the onset time for the appearance of the ground state CH_2 have been found to depend strongly on CO_2 laser output fluences. These results appear to have a strong bearing on the structure of the potential energy surfaces of the intermediate CH_2CO. A possible photolysis me- chanism is proposed to explain these experimental results.

关键词： CO nm Infrared multiphoton dissociation of aceticanhydride Figure