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DFT Calculation of Room Temperature Ionic Liquid 1-Ethyl-3-Methyl-Imidazolium Chlorocuprate (Ⅰ)

china Petroleum Processing & Petrochemical Technology 2008年第1期10卷 55-62页

作者： Lü Renqing Cao Zuogang (college of chemistry and Chemical engineering, china University of Petroleum (East china), Dongying 257061) college of chemistry and Chemical engineering China University of Petroleum (East China) Dongying 257061 China

The density functional theory （DFT） has been employed to investigate the electronic structures ofEMIM^＋（1-ethyl-3-methylimidazolium＋）, CuCl2^-, Cu2Cl3^- and EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs. Full optimization and frequency analyses of EMIM^＋, CuCl2^-, Cu2Cl3^-, eight initial EMIM^＋-CuCl2^-, and six initial EMIM^＋-Cu2Cl3^- geometries have been carried out using Gaussian-94 software-package at 6-3 I＋G （d, p） basis set level for hydrogen, carbon, nitrogen, chlorine atoms and the Hay-Wadt effective core potential for copper atoms. The electronic structures of the lowest energy of EMIM^＋-CuCl2^-, EMIM^＋-Cu2Cl3^- pairs, single EMIM^＋, CuCl2^-, and Cu2Cl3^- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-CuCl2^- pair conformer of the lowest energy was five ring moiety parallel to CuCl2^- plane with a distance of around 3.5,A, while EMIM^＋-Cu2Cl3^- pair conformer of the lowest energy was five ring moiety of EMIM^＋ perpendicular to Cu2Cl3^- plane with a distance of around 3.0 ,A between terminal chlorine atoms and 5-ring plane of EMIM^＋. The cohesion between cation and anion is electrostatic interaction and C-H---Cl hydrogen bonds are reinforced by charge assistance. The frequency analyses suggested that all stationary points are minimum points because of absence of imaginary frequency. The low energy of interaction caused by bulky asymmetry of EMIM^＋, and charge dispersion of cation and anion give rise to low melting point of ionic liquids EMIM^＋-CuCl2^-, and EMIM^＋-Cu2Cl3^- . The interaction energy caused by the distance between cations and anions was investigated by single point energy scan.

关键词： ionic liquid density functional theory 1-ethyl-3-methylimidazolium chlorocuprate (I)

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3D-QSAR studies on glycogen phosphorylase inhibitors by flexible comparative molecular field analysis

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Science china chemistry 2007年第4期50卷 568-573页

作者： ZHOU Peng1 & LI ZhiLiang1,2 1 college of chemistry and Chemical engineering, Chongqing University, Chongqing 400044, china 2 State Key Laboratory of Chemo/Biosensing and Chemometrics, Changsha 410082, china college of chemistry and Chemical engineering Chongqing University Chongqing China State Key Laboratory of Chemo/Biosensing and Chemometrics Changsha China

Canceling grids accommodating probes in comparative molecular field analysis (CoMFA), the idea of flexibleness is introduced into the CoMFA, and in combination with swarm intelligent algorithm which attempts to optimize distributions of diverse probes around drug molecules, a new 3D-QSAR method is proposed in this context as flexible comparative molecular field analysis (FCoMFA). In preliminary at-tempts to performing QSAR studies on 47 glycogen phosphorylase inhibitors, FCoMFA is employed and confirmed to be potent to exploring ligand-receptor interaction manners at active positions and thus to generating stable and predictable models. Simultaneously by an intuitive graphics regarding probe distribution patterns, impacts of different substituted groups on activities is also given an insight into.

关键词： flexible comparative molecular field analysis (FCoMFA) three-dimensional quantitative structure-activity relationship (3D-QSAR) particle swarm optimization algorithm (PSO) glycogen phosphorylase inhibitor probe distribution pattern

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Colloidal organic carbon in Huanghe, Changjiang and Qiantang River

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Chinese Science Bulletin 1998年第11期43卷 915-917页

作者： WANG Jiangtao college of chemistry and Chemical engineering, Ocean University of Qingdao, Qingdao 266003, china Callege of chemistry and Chemical engineering Ocean University of Qingdao Qingdao China

Cross-flow ultrafiltration techniques have been used to separate colloidal organic carbon (COC) from natural water, and COC in three water samples that were collected from Huanghe, Changjiang and Qiantang River was determined. On average, COC comprised about 68.6% of the total dissolved organic carbon. The abundance of COC suggested that COC could play important roles in input fluxes and biogeochemistry of organic carbon.

关键词： cross-flow ultrafiltration colloidal organic carbon.

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Crystal structure of a novel two-dimensional supramolecular network based on polyoxoanion and yttrium~Ⅲcoordination cation

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Science china chemistry 2005年第Z1期48卷 9-13页

作者： HE Shuiyang,PENG Ke,NING Wei,WANG Daqi & SHI Qizhen Department of chemistry,Northwest University and Shaanxi Key Laboratory of Physico-Inorganic chemistry,Xi’an 710069,china college of chemistry and Chemical engineering,Liaocheng University,Liaocheng 252059,china Department of chemistry Northwest University and Shaanxi Key Laboratory of Physico-Inorganic Chemistry Xi’an China college of chemistry and Chemical engineering Liaocheng University Liaocheng China

A novel compound (NH4)2Y(H2O)8[PMo10V2O40]·10H2O has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2Y(H2O)8 [PMo10V2O40]·10H2O single crystal, which crystallizes in the monoclinic system of a space group P21/C with a=0.9871(3) nm,b=1.5424(5) nm,c=2.7924(9) nm,β=94.183(5)°and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2O405- anion and the Y(H2O)83+ cation building blocks via hydrogen bonding exhibiting the porous structure.

关键词： crystal structure, polyoxoanion, yttrium, supramolecular network.

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Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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Wuhan University Journal of Natural Sciences 2004年第2期9卷 234-238页

作者： Huang Jian-ping 1,2, Chen Fang 1, Ai Xin-ping 1, He Zhi-ke 1 1. college of chemistry and molecular Sciences, Wuhan University, Wuhan 430072, Hubei, china 2. Department of Environmental engineering, Hubei Agricultural college, Jingzhou 434025, Hubei, china college of chemistry and molecular Sciences Wuhan University Wuhan Hubei China Department of Environmental engineering Hubei Agricultural College Jingzhou Hubei China

The interactions between metal ions and DNA have been studied by the resonance light scattering (RLS) spectra. In the acidic condition, the RLS signals of metal ions, especially the transition metal ions in group IB and IIB, were increased by DNA. And it is found that the enhancement of RLS signals is linear to the concentration of DNA, so the RLS method for DNA determination was proposed in the presence of Cu2+. On the optimum conditions, the linear range and the detect limit of ctDNA is 4×10?8–4×10?6 g· mL?1 and 1. 13×10?8 g·mL?1, respectively. The proposed method is successfully applied to determine the extracted plasmid DNA ofBacillus subtilis DB104. Key words resonance light scattering - DNA - metal ions CLC number O 657.3 Foundation item: Supported by National Natural Science Foundation of china (20275028) and the National Key Basic Research and Development Program (973 Program 2002CB211800).Biography: Huang Jian-ping(1964-), male, Associate professor, research direction: bioanalysis.

关键词： resonance light scattering DNA metal ions

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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 molecular engineering, Peking University, Beijing 100871, china 2. Department of chemistry, Hong Kong Baptist University, Hong Kong, china college of chemistry and molecular engineering Peking University Beijing China 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.

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Adsorption Breakthrough of Benzene in the Fixed Bed of Modified Activated Carbon under Different Humidity Conditions

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Journal of Wuhan University of Technology(Materials Science) 2010年第3期25卷 499-503页

作者：李晶 college of chemistry and Chemical engineering Zhongkai University of Agriculture and Engineering

The breakthrough curves of benzene and water on modified activated carbons（ACs） were ***-programmed desorption（TPD） experiments were conducted to measure the TPD curves of benzene and water on modified and unmodified ACs and to estimate the activation energy for the desorption of benzene on the modified *** with unmodified ACs,two modified ACs were prepared by using two different types of silane,designated by KH560 and *** results showed that the activation energy for the desorption of benzene on KH560/AC and 1706/AC was higher than that on unmodified *** addition,the activation energy for the desorption of water on KH560/AC and 1706/AC was lower than that on unmodified *** breakthrough curves of benzene obtained from the experimental observations under different humidity conditions were compared with the results of the TPD *** results show that the modified ACs are less affected by water,whereas the unmodified ACs are more affected by water,indicating that surface modification by organosilane compounds can improve the adsorption of benzene on the activated carbo,which weakens the adsorption of water.

关键词： activated carbon benzene water TPD activation energy of desorption breakthrough curves

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Luminescence resonance energy transfer based on β-NaYF_4:Yb,Er nanoparticles and TRITC dye

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Science china chemistry 2009年第10期52卷 1590-1595页

作者： SUN LingDong, GU JianQin, ZHANG ShuZhuo, ZHANG YaWen & YAN ChunHua Beijing National Laboratory for molecular Sciences, State Key Lab of Rare Earth Materials chemistry and Applications & PKU-HKU Joint Lab in Rare Earth Materials and Bioinorganic chemistry, college of chemistry and molecular engineering, Peking University, Beijing 100871, china Beijing National Laboratory for molecular Sciences State Key Lab of Rare Earth Materials Chemistry and Applications & PKU-HKU Joint Lab in Rare Earth Materials and Bioinorganic Chemistry College of Chemistry and Molecular Engineering Peking University Beijing China

β-NaYF4:Yb,Er nanoparticles (NPs) are one of the most efficient upconversion materials, which can convert near-infrared light to higher-energy light through multiple photon absorptions or energy transfer. In addition, they may be attractive alternative donors for luminescence resonance energy transfer (LRET) studies, because of their sharp absorption and emission profiles, high quantum yields, large anti-stokes shifts, long lifetime, low toxicity, and superior photo-stability. In principle, many problems of fluorescence resonance energy transfer (FRET), such as excitation of acceptors, emission overlaps between donors and acceptors, high background noise, potential toxicity, and instability, can be overcome using β-NaYF4:Yb,Er NPs as energy donors. Because the organic coating induced separation can significantly reduce the energy transfer efficiency and aqueous FRET system is difficult to be applied in devices, we demonstrate a novel NP-dye LRET system in solid state. The emission of the β-NaYF4:Yb,Er NPs at 539 nm overlaps with the absorption of the tetrametrylrhodarnine isothiocyante (TRITC), satisfying the requirement of LRET process. Since TRITC molecules are adsorbed on the β-NaYF4:Yb,Er NPs by an electrostatic interaction, the interaction distance is suitable for LRET without any further modulation. The resultant solid LRET system is ready for the further applications for devices.

关键词： upconversion emission β-NaYF4:Yb Er nanoparticles TRITC assembly luminescence resonance energy transfer (LRET)

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Biotic communities of the marine ecosystem in Meizhou Bay

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Journal of Environmental Sciences 1996年第1期8卷 48-56页

作者： Ren Jiuchang Cai Xiaoming (Center of Environmental Sciences,Peking University, Beijing 100871,china)Chen Bin(college of Life Sciences, Peking University, Beijing 100871, china )Li Peng(college of chemistry and molecular engineering, Peking University, Bei Ctr of Envmtl Sci Peking Univ Beijing China China

The current situation of biotic communities in Meizhou Bay is presented in this *** species composition,seasonal variation,and distribution of phytoplankton,zooplankton, red tide organisms,fishes,and benthos in Meizhou Bay were investigated,and the content of chlorophyll a and primary production and their seasonal variation were also *** water quality of Meizhou Bay was monitored by measuring the density of Escherichia coli. Results reveal that there is a great variety of species in Meizhou Bay and the water in Meizhou Bay is *** the individual numbers of various organisms are very low, especially those of ***,there are more than 40 species of red tide organisms and there exist opportunities of red tides between May and *** these demand cautious be taken in the future development of this area although it has great environment capacity.

关键词： biotic community marine ecosystem Meizhou Bay.

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Preparation of polystyrene/silica nanocomposites by radical copolymerization of styrene with silica macromonomer

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Science china chemistry 2007年第3期50卷 385-391页

作者： OU BaoLi1,2 & LI DuXin2 1 college of chemistry and Chemical engineering, Hunan University of Science and Technology, Xiangtan 411201, china 2 State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, china college of chemistry and Chemical engineering Hunan University of Science and Technology Xiangtan China State Key Laboratory of Powder Metallurgy Central South University Changsha China

A two-stage process has been developed to generate the silica-based macromonomer through surface-modification of silica with polymerizable vinyl groups. The silica surfaces were treated with excess 2,4-toluene diisocynate (TDI), after which the residual isocyanate groups were converted into polymerizable vinyl groups by reaction with hydroxypropylacrylate (HPA). Thus, polystyrene/silica nanocomposites were prepared by conventional radical copolymerization of styrene with silica macromonomer. The main effecting factors, such as ratios of styrene to the macromonomer, together with polymerization time on the copolymerization were studied in detail. FTIR, DSC and TGA were utilized to characterize the nanocomposites. Experimental results revealed that the silica nanoparticles act as cross-linking points in the polystytene/silica nanocomposites, and the glass transition temperatures of the nanocomposites are higher than that of the corresponding pure polystyrene. The glass transition temperatures of nanocomposites increased with the increasing of silica contents, which were further ascertained by DSC.

关键词： silica nanoparticles surface modification styrene radical copolymerization nanocomposites

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