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Synthesis and Crystal Structure of 4,6Di-tert-butyl-2.hydroxy-3-(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ ZHANG ZeYing\= (college of chemistry and {2. engineering, Peking University, beijing 100871, china) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

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１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

Applications of functionalized ionic liquids

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Science china chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1, ZHAO Dongbin2.3, FEI Zhaofu2.& WANG Lefu1 1. Department of Chemical engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South china Uni-versity of Technology, Guangzhou 510641, china 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1015 Lausanne, Switzerland 3. PKU Green chemistry Center, beijing National Laboratory for molecular Sciences, college of chemistry and molecular engineering, Peking University, beijing 100871, china 1. Department of Chemical engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

Utilization of a spiropyran derivative in a polymeric film optode for selective fluorescent sensing of zinc ion

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Science china chemistry 2006年第3期49卷 246-255页

作者： ZHANG Ying1, SHAO Na1, YANG Ronghua1, LI Ke’an1, LIU Feng1, CHAN Winghong2.& MO Tian2.1. college of chemistry and {2. engineering, Peking University, beijing 100871, china 2. Department of chemistry, Hong Kong Baptist University, Hong Kong, china 1. college of chemistry and {2. engineering Peking University Beijing 100871 China 2. Department of chemistry Hong Kong Baptist University Hong Kong China

A new spiropyran derivative was synthesized and first utilized in a polymericfilm-based optical sensor for zinc ion. Spiropyrans, combining the characteristics of metal bindingand signal transduction, show potential function in the design of optical chemical sensors(optodes) toward metal ions. When embedded in a plasticized poly (vinyl chloride) (PVC) membrane,the newly synthesized spiropyran derivative 1 exhibits obvious fluorescence enhancement at 630 nm inthe presence of zinc ion in aqueous solution. With the optimum condition described, the optodemembrane responds to zinc ion over a dynamic range of 4.94x10^(-7) to 4.15x10^(-4)mol·L^(-1), witha detection limit of 1.51x10^(-7) mol·L^(-1). The membrane not only displays excellentphotostability, reproducibility and reversibility, but also exhibits high selectivity toward zincion over transition metal ions including Hg^(2.), Cd^(2.), Pb^(2.), Cu^(2.), Fe^(3+) and commoncationic ions presented in the physiological fluids.

关键词： spiropyran, sensor, PVC membrane, zinc ion, fluorescent spectroscopy.

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2.F film optically transparent electrode

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Science china chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2.& NIU Shuyan1,2.1. college of chemistry and {2. engineering, Qingdao University of Science and Technology, Qingdao 2.6042. china 2. college of chemistry and Chemical engineering, Ocean University of china, Qingdao 2.6003, china Correspondence should be addressed to Jiao Kui 1. college of chemistry and {2. engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and Chemical {2. Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2.F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

STABILITY OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)MICROGEL DISPERSION AND ADJUSTMENT OF THE HYDROPHOBICITY IN THE MICROGELS

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Chinese Journal of Polymer Science 2005年第6期23卷 635-642页

作者： Qing-de Chen Xing-hai Shen and Hong-cheng Gao Department of Applied chemistry,college of chemistry and molecular engineering,Peking University,beijing 100871,china Peking Univ Dept Appl Chem Coll Chem & Mol Engn Beijing 100871 Peoples R China

In the UV-Vis spectra of pure light-scattering systems, there is an exponential relationship between absorbance and wavelength （A = Kλ^-n）. Here, the exponent n is named as flocculation-coagulation parameter. In the present paper, the effects of different additives on the stability of poly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP）） microgel dispersion were studied in detail via this parameter. The results showed that the stability of the dispersion mainly comes from the ionization of pyridine groups, making the microgel positively charged on its surface. This was confirmed by the measurement of Zeta potential and the result of conductometric titration. The result of fluorescence analysis indicated that the hydrophobicity in the microgels is enhanced with the increase in total 4-VP unit content.

关键词： Microgel dispersion(s) 4-Vinylpyridine Flocculation-coagulation parameter Zeta potential

EFFECTS OF L-PHENYLALANINE ON THE RADIATION SYNTHESIS OF POLY(N,N'-METHYLENEBISACRYLAMIDE-co-4-VINYLPYRIDINE)(MICRO)GELS

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Chinese Journal of Polymer Science 2005年第6期23卷 643-650页

The effects of L-phenylalanine （L-Phe） on the synthesis ofpoly（N,N＇-methylenebisacrylamide-co-4-vinylpyridine）（poly（Bis-co-4-VP））（micro）gels by γ-ray irradiation were studied. The addition of L-Phe could not only decrease the gelation dose （Dg） of the synthesis obviously, but also transform the morphology of copolymer from microgel to gel. In addition, the swelling ability of the （micro）gels was also affected in the presence of L-Phe. The decrease of Dg was ascribed to the effect of pH, while the transformation of the morphology was ascribed to the effect of L-Phe on the stability of the poly（Bis-co-4-VP） microgel. Such an effect was confirmed further as compared with the effects of L-alanine, L-glutamic acid, L-arginine, sulfuric acid and aqueous ammonia.

关键词： L-Phenylalanine γ-Ray irradiation Gelation dose Morphology transformation (Micro)gel

Modeling the intracellular dynamics for Vif-APO mediated HIV-1 virus infection

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Chinese Science Bulletin 2010年第22期55卷 2329-2340页

作者： WANG Yi1,2.& LAI LuHua1,3 1 Center for Theoretical Biology, Peking University, beijing 100871, china 2.School of Physics, Peking University, beijing 100871, china 3 BNLMS, State Key Laboratory for Structural chemistry of Unstable and Stable Species, college of chemistry and molecular engineering, Peking University, beijing 100871, china Center for Theoretical Biology Peking University Beijing 100871 China School of Physics Peking University Beijing 100871 China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The viral infectivity factor (Vif) was found to be essential for controlling HIV-1 virus infectivity. It targets cellular antiviral proteins in APOBEC family (APO) to trigger its fast degradation and inhibits APO packaging into nascent virion. In the present study, we propose a mathematical model to quantitatively study the intracellular dynamics of these typical virus-host interactions. Four sets of published experimental data were compared with simulation results to justify the model. Systematic parameter sensitivity and perturbation analysis showed that parameters related to APO are crucial to the infectivity of newly synthesized HIV-1 virus. Interestingly, we discovered that the synthesis rate of the viral structure protein Gag and the required number per nascent virion are optimized to achieve high virion production with minimal level of packaged APO, and large portion of model parameters are beneficial to virus only within a relatively small range. Furthermore, minor variations in several parameters related to viral protein Tat, the activator of viral RNA synthesis, were found to induce switch-like behaviors on both incorporated Vif and APO. These findings may provide new insights for understanding the high mutation rate of HIV-1 virus and its latency, as well as help identify key targets for therapeutic design.

关键词：病毒感染载脂蛋白 HIV 细胞内动力学抗病毒蛋白建模介导

PROPERTIES OF POLYURETHANE ELASTOMERS BASED ON POLY (OXYETHYLENE-co-OXYTETRAMETHYLENE) DIOL

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Chinese Journal of Polymer Science 2001年第4期19卷 371-376页

作者： Chen-yu Su Guang-li Zhang Hong-zhi Zhang Department of Polymer Science and engineering college of {2. and molecular engineering Peking University beijing 100871, china Peking Univ Dept Polymer Sci & Engn Coll Chem & Mol Engn Beijing 100871 Peoples R China

Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2.00, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.

关键词： polyurethane poly(oxyethylene-co-oxytetramethylene) diol low temperature resilience heteropolyacid-ethylene oxide initiator system

Status of study on biological and toxicological effects of nanoscale materials

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Science china chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, beijing 100049, china {2., Peking University, beijing 100871, china 3. Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, beijing 100083, china 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. college of chemistry and molecular engineering Peking University 100871 Beijing China 3. Department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.