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SYNTHESIS OF PERFLUORO-1-OCTANESULFONATED FULLERENE AND THE FRICTION PROPERTIES OF ITS THIN FILM

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Chinese Journal of polymer science 2002年第5期20卷 397-400页

作者： Lan Huang Shuang Fan Fang Wei Xin-sheng Zhao Jin-xin Xiao Bu-yao Zhu college of chemistry and Molecular engineering {3. university beijing 100871, china peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China

A star-shaped compound of perfluoro-1-octanesulfonated fullerene was synthesized. The measurement of the friction for its spin-coating film by friction force microscopy (FFM) reveals that the films possess lower frict... 详细信息

关键词： perfluoro-1-octanesulfonated fullerene thin film friction force microscopy (FFM)

Oxidative Methylation of Toluene with Methane over Basic Zeolite Catalysts Promoted with Alkali Metal Bromides and Alkali Metal Oxides

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Chinese Chemical Letters 2000年第9期11卷 827-830页

作者： Ling Ping zhou Wei LI Ke Yi TAO Xuan Wen LI He Xuan LI college of chemistry and Molecular {3., peking university, beijing 100871 department of chemistry, Nankai university, Tianjin 3.0071 peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China Nankai Univ Dept Chem Tianjin 300071 Peoples R China

The catalytic effects for the oxidative methylation of toluene with methane over the basic zeolite catalysts prepared by promoting KY, KX, KM, KZSM-5 or KP with alkali-metal bromides and alkali-metal oxides have been investigated comparatively. The alkali-metal bromides promoted substrates are more effective than the alkali-metal oxides promoted systems. Moreover, the NaBr promoted systems are more active than KBr promoted systems. The most effective catalytic system (8wt%NaBr)/KZSM-5 gave a toluene conversion as high as 76.3. and a total C-8 selectivity of 76.4% (styrene/ethylbenzene=9.76) resulting in a total C-8 yield of 58.3..

关键词： styrene methane oxidative methylation alkali-metal oxides alkali-metal bromides

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, Guang{3. 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,{13., 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

AlkB recognition of a bulky DNA base adduct stabilized by chemical cross-linking

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science china chemistry 2010年第1期53卷 86-90页

作者： YI Chengqi1 & HE Chuan1,2 1department of chemistry,{3. of Chicago,Chicago,Illinois 6063.,USA 2department of Chemical Biology,college of chemistry and Molecular engineering,peking {3.,beijing 100871,china 1. department of chemistry University of Chicago Chicago Illinois 60637 USA2. Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

*** AlkB is a direct DNA/RNA repair protein that oxidatively reverses N1 alkylated purines and N3.alkylated pyrimidines to regular *** crystal structures have revealed N1-methyl adenine(1-meA) recognition by AlkB and a unique base flipping mechanism,but how the AlkB active site can accommodate bulky base adducts is largely *** a previously developed chemical cross-linking technique,we crystallized AlkB with a duplex DNA containing a caged thymine base(cagedT).The structure revealed a flexible hairpin lid and a reorganized substrate recognition loop used by AlkB to accommodate *** observations demonstrate,at the molecular level,how bulky DNA adducts may be recognized and processed by AlkB.

关键词： DNA/RNA repair AlkB caged thymine disulfide cross-linking bulky base adduct

FORMATION OF MESOPHASE MONO-DOMAINS AND MICRO-STRUCTURES IN THIN FILMS OF A SERIES OF COPOLYETHERS CONTAINING BOTH ODD-NUMBERED METHYLENE UNITS

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Chinese Journal of polymer science 2001年第4期19卷 391-397页

作者： feng-chao Xie Jie-ping Liu Dong-hang Yan Tian-bai He Ru-qing Zheng Er-qiang Chen State Key Laboratory of {3. Physics and chemistry, Changchun Institute of Applied chemistry, Chinese Academy of sciences, Changchun 13.022, china department of {3. science and engineering college of chemistry peking university beijing 100871, china Chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

The structural and morphological evolution of mono-domains in thin films has been investigated for a series of liquid crystalline (LC) copolyethers. The copolyethers studied were synthesized by the reaction of 1-(4-hydroxy-4 ' -biphenylyl)-2-(4-hydroxyl-phenyl)propane (TPP) with 1,7-dibromoheptane and 1,11-undecane at different compositions (coTPPs-7/11). In contrast to the solution-cast thin films without annealing, which exhibit the isotropic homogeneous molecular orientation, mono-domains with a homeotropic alignment were found in coTPP-7/11(5/5) after the thin films were annealed in the high-temperature columnar phase (Phi '). Similar to the nucleation process in polymer crystallization, transmission electron microscopic observations show that small mono-domains appear in the initial stage of annealing, where molecules form a uniaxial in-plane chain orientation. With increasing annealing time, the molecular orientation gradually became tilted with respect to the substrate surface, and finally, a uniaxial homeotropic molecular orientation was achieved after a prolonged annealing time. The lateral size of mono-domains was found to increase continuously with annealing time and grew into a circular shape, indicating an isotropic lateral growth scheme which implies a hexagonal molecular packing proved by the electron diffraction experiments.

关键词： main-chain liquid crystalline polymer structure morphology

FABRICATION AND AFM/FFM STUDIES OF C_(60)-CONTAINING POLYELECTROLYTE SELF-ASSEMBLED FILMS

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Chinese Journal of polymer science 2002年第3期20卷 197-203页

作者： Lan Huang Xiao-rong Hou Yuan-kang He Xiao-liang Zheng Fang Wei Xin-sheng Zhao Wei-xiao Cao college of chemistry & Molecular engineering {3. university beijing 100871, china peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China

An initial investigation on the roughness and frictional properties of the self-assembled thin films from polyelectrolytes is presented. Star-shaped C-60-Poly(styrene-maleic anhydride) was successful prepared. The multilayer thin films have been fabricated on mica with diazoresin as the cationic polyelectrolyte and hydrolyzed star-shaped C-60-poly(styrene-maleic anhydride) as the anionic polyelectrolyte via self-assembly technique. The crosslinking structure of the films is formed from the conversion of ionic bond to covalent bond after UV irradiation. AFM/FFM investigations provide insights into the roughness and frictional properties on a microscale. The roughness depends strongly on the number of film layers in the case of C-60-containing films. The frictional forces of the films exhibited a well behaved non-linear relationship in response to the change of applied load. It supports the prediction of enhanced load-bearing property Of C60-containing thin films.

关键词： star-shaped C-60-poly(styrene-maleic anhydride) self-assembly film AFM/FFM roughness frictional properties

Photorefractive Effect in Poly(N-vinylcarbazole)-Based Composite Sensitised by C_(60)

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Chinese Chemical Letters 1997年第9期8卷 807-810页

作者： Zhi Jie ZHANG Yi Wang CHEN Yuan Kang HE and Hui Ying CHEN(Institute of polymer science, college of {3., peking university, beijing, 100871)Zhi Jian CHEN Shu feng WANG and qi Huang GONG(department of Physics, Mesoscopic Physics Laboratory, peking U Institute of polymer science College of Chemistry Peking University Beijing 100871 China department of Physics Mesoscopic Physics Laboratory Peking University Beijing 100871 China

A new PVK-based photorefractive polymer composite sensitized by C60 and doped with a higher content of EO chromophore was prepared. The high optical quality thin-film was formed between two ITOcovered glass electrodes. Two-beam-coupling (2BC) experiment was performed by using a He-Ne laser (at wavelength 63..8nm), and an obvious photorefractive performance was observed. The dependence of two-beamcoupling gain coefficient on the applied poling dc electric field was measured.

关键词： Photorefractive Effect in Poly Based Composite Sensitised by C N-vinylcarbazole Rev

Thermodynamic evaluation and hydrothermal preparation of K_xNa_(1-x)NbO_3

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Rare Metals 2008年第4期27卷 371-377页

作者： ZHANG Ci LV Haijun GUO Min ZHANG Mei WANG Xidong department of Physical chemistry University of Science and Technology Beijing Beijing 100083 China college of engineering. peking {3. Beijing 100871 China

The Gibbs free energies of reaction △rGτ of KNbO3.and NaNbO3.were calculated and then that of KxNa1-xNbO3.was estimated. On the basis of the thermodynamic calculation results, the hydrothermal temperatures were designed at 100, 160, and 23.℃ respectively. However, NaNbO3.was prepared when the heating temperature was higher than 160℃, and KNbO3.and KxNa1-xNbO3.were obtained at 23.℃, suggesting that only at a higher temperature the kinetic requirement is satisfied. According to the X-ray diffraction results, both the solid solutions, NaNbO3.based solid solution, Na1-xKxNbO3. and KNbO3.based solid solution, K1-xNaxNbO3. were hydrothermally synthesized in 6 mol/L alkali （NaOH and KOH） solution at 23.℃.

关键词： KNbO3 NaNbO3 thermodynamic calculation hydrothermal synthesis Gibbs free energy

Syntheses, structures and magnetic properties of a family of one-dimensional M(Ⅱ)-lanthanide(Ⅲ) (M = Ni(Ⅱ) and Zn(Ⅱ)) coordination polymers

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science china chemistry 2007年第3期50卷 308-317页

作者： ZHANG Wen, ZHAO Fei, LIU Tao & GAO Song beijing National Laboratory for Molecular sciences, State Key Laboratory of Rare Earth Materials chemistry and Applications, {3. of chemistry and Molecular engineering, peking university, beijing 100871, china 1. beijing National Laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A series of 1D nickel(II)/zinc(II)-lanthanide(III) coordination polymers, [M(μ-L)2Ln(NO3.3.n·solvents (HL = bis(2-pyridylcarbonyl)amine; M = Ni, Ln = Gd (1·NiGd), Tb (2·NiTb), Dy (3.NiDy), Ho (4·NiHo), Y (5·NiY); M = Zn, Ln = Gd (6·ZnGd), Tb (7·ZnTb), Dy (8·ZnDy), Ho (9·ZnHo); solvents = H2O or H2O-ethanol), was synthesized and characterized. All of the complexes are isostructural at 293.K and crystallize in the orthorhombic space group Fddd. Magnetic measurements were performed on 1―9, where weak ferromagnetic interaction is found in 1·NiGd, ferromagnetic interaction in 2·NiTb and 3.NiDy, and antiferromagnetic interaction in 4·NiHo. A remarkable dc magnetic field dependence of ac susceptibilities was found in this series of complexes.

关键词： nickel lanthanide 3.-4f coordination polymer magnetic property