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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,{3. University of Petroleum (East{3.), 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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Drag reduction of flow boiling with polymer additives

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Journal of Central South University of Technology 2001年第2期8卷 143-146页

作者： QIU Yun ren 1,CHEN Wei ping 2,SI Qin 3.(1.college of Chemistry and chemical engineering, Central South University, Changsha 4.0083.{3. 2.Editorial Office of Journal of Central South University, Changsha 4.0083.{3. 3.college of chemical E college of Chemistry and chemical engineering Central South University Changsha China Editorial Office of Journal of Central South University Changsha China college of chemical engineering Tianjin University Tianjin China

The drag reducing effect of polymer additive aqueous solution was investigated in flow boiling, and the polymer additives were two kinds of polyacrylamide (PAM) with relative molecular mass about 2.56×10 6 and 8.55×10 6. The frictional pressure drop was calculated according to the measured total pressure drop. The results show that the flow drag of flow boiling is reduced by adding a small amount of PAM to water when heat flux is in the range of 15.1 kW·m -2 to 4..0 kW·m -2 , when the mass fraction of PAM is higher than 2.0×10 -5 , the drag reducing effect is obvious. Drag reducing effect of PAM, whose relative molecular mass is 8.55×10 6, is slightly better than that of 2.56×10 6 at the same mass fraction, and the greater the flow rate of the additive solution, the better the effect of the drag reduction.

关键词： polymer additive flow boiling drag reduction pressure drop

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Mesoporous Si-MCM-4. membrane prepared by pore-filling method

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Science china(Technological Sciences) 2010年第4期53卷 1064-1068页

作者： XU DeKan & FAN YiQun State Key Laboratory of Materials-Oriented chemical engineering,college of Chemistry and chemical engineering,Nanjing University of Technology,Nanjing 210009,china State Key Laboratory of Materials-Oriented chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology

Mesoporous MCM-4. membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal *** support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support *** SEM showed that the MCM-4. membrane was composed of tightly-connected spherical *** single gas N2 and H2 permeation experiments confirm that crack-free membrane could be prepared by pore-filling method.N2 permeance of MCM-4. membrane,synthesized by secondary growth,can reach 5.66×10-7 mol/Pa·s·m2,and the H2/N2 separation factor was 3.4. under trans-membrane pressure of 0.05 MPa.

关键词： MCM-4. mesoporous membrane pore-filling

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SYNTHESIS OF NOVEL THIOPHENEDIMETHYLENE BRIDGED HOMOBINUCLEAR METALLOCENES AND THEIR CATALYTIC PROPERTIES FOR ETHYLENE POLYMERIZATION

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Chinese Journal of Polymer Science 2006年第1期24卷 21-27页

作者： Xi-jie Liu Jun-quan Sun Hai-ying Zhang Xiao-hui Xiao and Feng Lin Department of chemical engineering,college of Material and chemical engineering,Zhejiang University,Hangzhou 3.0027,china Department of chemical engineering College of Material and Chemical Engineering Zhejiang University Hangzhou 310027

By treating disodium（thiophenedimethylene）dicyclopentadienide C4.2S（CH2C5H4.a）2 with two equivalent of CpTiCl3.or CpZrC13.DME at 0℃ in THF, two new thiophenedimethylene bridged binuclear metallocenes [Cl2MC5H5][C5H4.H2C4.2SCH2C5H4.[C5H5MCl2] （M = Ti 3. M = Zr 4. were synthesized in high yield and their structures were characterized by ^1H-NMR. These complexes were used as catalysts for ethylene polymerization in the presence of methylaluminoxane （MAO）. The effects of polymerization temperature, time, concentration of catalyst, molar ratio of MAO/Cat on polymerization were studied in detail. The catalytic activities of thiophenedimethylene bridged binuclear metallocene catalysts （3. 4. reached 2.4. × 10^5 g PE mol^-1 cat^-1· h^-1, 9.61 × 10^5 g PE mol^-1 · cat^-1· h^-1 respectively, which are higher than that of pheneyldimethylene bridged binuclear metallocene catalysts and much higher than that of corresponding mononuclear metallocenes （Cp2TiCl2 and Cp2ZrCl2）. The molecular weight distribution curves of polyethylenes produced by binuclear metallocene catalysts （3. 4. and by mononuclear metallocene catalyst have only single peak, but the former （MWD = 3.5-4.7） is obviously broader than the latter （MWD = 2.0-2.2）.

关键词： Binuclear metallocene Thiophenedimethylene bridged Ethylene polymerization.

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Interface-directed sol-gel:direct fabrication of the covalently attached ultraflat inorganic oxide pattern on functionalized plastics

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Science china Chemistry 2010年第1期53卷 173-182,287-288页

作者： GAN ShengHua,YANG Peng & YANG WanTai State Key Laboratory of chemical Resource engineering college of Materials Science and engineering,Beijing University of chemical Technology,Beijing 100029,china State Key Laboratory of chemical Resource engineering college of Materials Science and engineering Beijing University of Chemical Technology Beijing China

For plastic electronics and optics,the fabrication of smooth,transparent and stable crack-free inorganic oxide films(and patterning) on flexible polymeric substrates with strong bonding strength and controllable thickness from nanometers to micrometers is a key but still remains a *** versatile inorganic oxides,silica oxide film as SiOx is especially important because this semiconductor material could provide crucial properties in devices or serve as a base layer for further multilayer *** this paper,we describe a new interface-directed sol-gel method to fabricate flexible high quality silicon oxide film onto commodity *** resulting crack-free silica film has strong covalent bonding with polymer substrates,homogeneous morphology with ultralow roughness,highly optical transparency,tunable thickness from nm to μm,and easy patterning *** fabrication strategy relies on a novel photocatalytic oxidation reaction by photosensitive ammonium persulfate(APS),which is able to fabricate highly reactive hydroxyl monolayer surface on inert polymeric *** kind of hydroxylated surface could serve as nucleation and growth sites to initiate surface sol-gel *** a result,well-defined SiOx film deposition(gelation) occurs,and patterned hydroxylation regions could be easily utilized to induce the formation of patterned oxide film *** strategy also excludes the requirements of clean room and vacuum devices so as to fulfill low-cost and fast fabrication *** application examples from such high quality SiOx layer onto plastics are given but should not be limited within *** is that oxygen permeation rate of SiOx deposited polymer film decreases 25 times than pristine polymer substrate,which is good for the potential packaging *** other one is that silanization monolayer,for example,3.aminopropyltriethoxysilane(APTES),could be successfully constructed onto silica layer through classical silanization reac

关键词： surface patterning silicon oxide sol-gel polymer surface modification functional coatings

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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.{3. 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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Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science china Chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3.& YI JianMin1,2 1 Department of Chemistry and chemical engineering, Hunan Institute of Science and Technology, Yueyang 4.4.00, china 2 {3. of Chemistry and chemical engineering, Central South University, Changsha 4.0083. china 3.{3. of Pharmaceutical Science, Central South University, Changsha 4.0078, china Department of Chemistry and chemical engineering Hunan Institute of Science and Technology Yueyang China college of Chemistry and chemical engineering Central South University Changsha China college of Pharmaceutical Science Central South University Changsha China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.4.,0.89 and 2.4.,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

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Cycloaddition mechanism for the resin-OsO_4.catalyzed of styrene: A DFT study

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Science china Chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2 1 college of chemical engineering, Gansu Unite University, Lanzhou 73.000,{3. 2 college of Chemistry and chemical engineering, Sun Yat-sen University, Guangzhou 510275,{3. college of chemical engineering Gansu Unite University Lanzhou China college of Chemistry and chemical engineering Sun Yat-sen University Guangzhou China

The postulated intermediates in the base-free and base-assisted addition of OsO4.to styrene have been investigated at the B3.YP/6-3.1G** level of the theory. N(CH3.2(Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2+3. addition was found to be favorable with an activation of 4..00 kJ/mol. In contract, the reaction barriers for the [2+2] cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

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Quantitative detection of ING1 mRNA under different gene regulation based on molecular beacon

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Chinese Science Bulletin 2006年第17期51卷 2059-2064页

作者： LIU Bin1,2,3.4. WANG Kemin1,2,3.4. XIAO Zhiqiang5,6, WANG Wei1,3.4. TAN Weihong1,2,3.4. SUN Yi5,6, TANG Hongxing1,3.4.& YANG Xiaohai1,3.4.. State Key Laboratory of Chemo/Biosensing and Chemometrics, Hu- nan University, Changsha 4.0082, china 2. Life Science and Biotechnology Institute, Hunan University, Chang- sha 4.0082, china 3. Chemistry and chemical Engineer {3., Hunan University, Changsha 4.0082, china 4. Hunan engineering Research Center for Bio-Nanotechnology, Hunan University, Changsha 4.0082, china 5. Medical Experiment Research Center, Xiangya Hospital, Central South University, Changsha 4.0008, china 6. Key Laboratory of Cancer Proteomics of Chinese Ministry of Health, Changsha 4.0008, china State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan University Changsha China Life Science and Biotechnology Institute Hunan University Changsha China Chemistry and chemical Engineer college Hunan University Changsha China Hunan engineering Research Center for Bio-Nanotechnology Hunan University Changsha China Medical Experiment Research Center Xiangya Hospital Central South University Changsha China Key Laboratory of Cancer Proteomics of Chinese Ministry of Health Changsha China

The effects of drug treatment, gene transfection, and p53.RNA interference (RNAi) on level of ING1 mRNA in tumor cells were quantitatively detected with the help of ING1 molecular beacon (MB)/cRNA standard curve based on MB detection technology. Results showed that the level of ING1 mRNA could be upregulated by 5-FU treatment or ING1 transfection in low expression cell line of MCF-7 and be inhibited by silencing p53.with RNAi technology in normal expression cell line of CNE2. The level of ING1 varied from 7.7×10?16 to 53.4. 10?16 mol/μg total RNA of tumor cells. The results not only provided evidence for the regulation effects of gene expression but also were applied to investigat- ing the interaction of multigenes on signal transduc- tion pathway.

关键词： ING1 RT-PCR 定量分析分子信号 mRNA

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Characterzation and separation of Al_(13. species using gel-filtration chromatography

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Science china Chemistry 2006年第4期49卷 326-331页

作者： CHU Yongbao1,2, GAO Baoyu1, YUE Qinyan1, WANG Yan1 & WANG Shuguang1 1. School of Environmental Science and engineering, shandong University, jinan 250100,{3. 2. {4. of Material and Environment, Qingdao University of Science and Technology, Qingdao 26604.,{3. School of Environmental Science and engineering Shandong University Jinan China college of Material and Environment Qingdao University of Science and Technology Qingdao China

A polyaluminum chloride (PAC) sample was prepared using a slow alkalinetitration method. The Bio-Gel P-100 gel column chromatographic technique was used to separate andcharacterize the various forms of aluminum present in the prepared PAC solution. The effluents froma gel column were monitored using online chemical method: AI-Ferron timed complexationspectropho-tometry and by ^(27)Al nuclear magnetic resonance (NMR) spectroscopy. Effects ofdifferent experimental conditions such as eluent flow rate, ionic strength and pH on separation ofAl_(13. were investigated. Experimental results indicated that molecule size exclusion was not theonly parameter affecting the column chromatographic separation efficiency of Al_(13. but moleculecharge as well. Reducing the eluent flow rate, increasing the ionic strength and suitable pHresulted in increase in the separation efficiency. Experimental results clearly indicated that byvarying the experimental conditions, it is possible to produce pure Al_(13. species using a gelcolumn chromatographic technique.

关键词： Al13 species, column chromatography, polyaluminum chloride (PAC), separation and purification.

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