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Study on Syntheses and Characterizations of Polymethylphenethylsilane, Polymethylcyclohexylsilane and their Copolymers

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Journal of central south {2. 2000年第2期12卷 92-96页

作者： HU Hui ping 1,HUANG Ke long 1,PAN Chun yue 1,CHEN De ben 2.(1 college of chemistry and Chemical Engineering, {2. south university of Technology, Changsha 410083, china 2.Department of chemistry, Sichuan university, Chengdu 610064, china 1. college of chemistry and Chemical Engineering Central South University of Technology 410083 Changsha China 2. Department of chemistry Sichuan University 610064 Chengdu China

The effects of adding cosolvents of diglyme and 15-crown-5 to the reaction mixture of Wurtz-type coupling of dichlorosilanes on the yield and relative molecular mass dispersity of polymethylphenethylsilane(PMPES) were discussed. The results show that addition of 10%(volume ratio of diglyme to toluene) diglyme as a cosolvent to the reaction mixture leads to the yield increase of PMPES with a monomodal distribution of relative molecular masses. Adding 10%diglyme to the reaction mixtures, the yields of polymethylcyclohexylsilane(PMCS) and copolymers (polymethylphenethylsilane-co-methylcyclohexylsilane), (the molar ratios of methylphenethyldichlorosilane to methylcyclohexyldichlorosilane were 2.0, 1.0 and 0.5, and the copolymers were abbreviated by Copolymers I, II, III, respectively) are 47%, 52., 54%, 53%, respectively. Their relative molecular masses ([`(M)]w )(\bar M_w ) almost reach 105. These polysilanes were characterized by 1H-NMR, IR and UV absorption spectrum.

关键词： polysilane cosolvent synthesis characterization

A Nickel-Manganese-Modified Low Zinc Phosphate Solution for Cathode-Electrophoretic Painting of Steel Substrates

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材料热处理学报 2004年第5B期25卷 1159-1162页

作者： LIBao-song LINAn GANFu-xing ZHANGXu-jian collegeofResource＆EnvironmentScience WuhanUniversityWuhanChina wuhanBoxinPaintingMaterials＆InstrumentsCorporation WuhanChina

Phosphate coatings are partially dissolved in the cathodic area during the cathode-electrophoretic painting processes causing the result that the coatings adhesion, corrosion protection, alkaline resistance are decreased. Furthermore, the service life of the coated production will be shortened. The addition of Ni2., Mn2. to the phosphating bath to improve the corrosion stability, alkaline resistance, as well as the adhesion of coating layers is studied in the article. These heavy metals do not only catalyse the surface reactions but generate a more corrosion resistant surface. We perfected the trecation phosphate solution by reducing the sludge, accelerating the phosphating reactions, improving corrosion protection and alkaline resistance. More even and finer grain structures, excellent corrosion resistance were obtained compared to the traditional phosphating technique.

关键词：磷化处理电泳涂镀耐蚀性抗碱性钢

The toxicity of Cu^(2.) to Microcystis aeruginosa using dielectric spectroscopy

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Science china chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2.1college of chemistry,Beijing Normal {2.,Beijing 100875,china 2.0} of life Science,Beijing Normal {2.,Beijing 100875,china 1. college of chemistry Beijing Normal University Beijing 100875 China2. College of Life Science Beijing Normal University Beijing 100875 China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2. solution to Microcystis *** was found that 0.04 mM Cu2. had no effect on dielectric increment,whereas the Cu2. concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2. on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2. at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2. or Mg2. did not protect *** cells from 1 mM Cu2. *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

Identification of one peptide which inhibited infectivity of avian infectious bronchitis virus in vitro

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Science china(life Sciences) 2006年第2期49卷 158-163页

作者： PENG Bo1, CHEN Hanyang1, TAN Yadi1,2. JIN Meilin1,2. CHEN Huanchun1,2.& GUO Aizhen1,2.1. Laboratory of Animal Virology, college of Veterinary Medicine, Huazhong Agricultural university, {2. 430070, china 2. National Key Laboratory of Agricultural Microbiology, Huazhong Agricultural university, {2. 430070, china 1. Laboratory of Animal Virology College of Veterinary Medicine Huazhong Agricultural University Wuhan 430070 China 2. National Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan 430070 China

Purified avian infectious bronchitis virus (IBV) was used to screen a random phage dis-play peptide library. After the fourth panning, 10 positive phages were sequenced and characterized. The phages specifically inhibited IBV infectivity in HeLa cells and blocked IBV haemagglutination. One linear peptide “GSH HRH VHS PFV” from the positive phages with the highest neutralization titer was synthesized and this peptide inhibited IBV infection in HeLa as well. The results may contribute to development of antiviral therapeutics for IBV and studying the determinants for viral and cell interac-tion.

关键词： avian infectious bronchitis virus, phage display, peptides.

Effects of dragon’s blood resin and its component loureirin B on tetrodotoxin-sensitive voltage-gated sodium currents in rat dorsal root ganglion neurons

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Science china(life Sciences) 2004年第4期47卷 340-348页

作者： LIU Xiangming1, CHEN Su1, YIN Shijin1 & MEI Zhinan2.1. Department of Biological & Medical Engineering, south-central university for nationalities, wuhan 4.0074,{2. 2. college of chemistry & Biological Technology, south-central university for nationalities, wuhan 4.0074,{2. 1. Department of Biological & Medical Engineering South-Central University for Nationalities 430074 Wuhan China 2. college of chemistry & Biological Technology South-Central University for Nationalities 430074 Wuhan China

Using whole-cell patch clamp technique on the membrane of freshly isolated dorsal root ganglion (DRG) neurons, the effects of dragons blood resin and its important component loureirin B on tetrodotoxin-sensitive (TTX-S) voltage-gated sodium currents were observed. The results show that both blood resin and loureirin B could suppress TTX-S voltage-gated sodium currents in a dose-dependent way. The peak current amplitudes and the steady-state activation and inactivation curves are also made to shift by 0.05% blood resin and 0.2.mmol/L loureirin B. These results demonstrate that the effects of blood resin on TTX-S sodium current may contrib-ute to loureirin B in blood resin. Perhaps the analgesic effect of blood resin is caused partly by loureirin B directly interfering with the nociceptive transmission of primary sensory neurons.

关键词： blood resin,loureirin B,dorsal root ganglion neurons,tetrodotoxin -sensitive sodium channel.

Characterization and Electrochemical Properties of LiMn_2._4 Thin Films Prepared by Solution Deposition

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Journal of wuhan university of Technology(Materials Science) 2006年第3期21卷 54-56页

作者：吴显明 college of chemistry and Chemical Engineering Jishou UniversityJishou 416000China

LiMn2.4 thin films were prepared by solution deposition using lithium acetate and manganese acetate us raw materials. The phase constitution and surface morphalogy were observed by X-ray diffraction and scanning electron microscopy. The electrochemical properties of the thin films were studied by cycilc voltammetry, charge- discharge experiments and impedance spectroscopy in 1 mol· L^-1 LiPF6 / EC- DMC solution using lithium metal as both the counter and reference electrodes. The films prepared by this method are of spinel phase. The lattice parameter increases with the annealing temperature aud annealing time. The film annealed at 750 ℃ for 30 minutes has the highest capacity of 34.5 μAh ·cm^- 2.μm^-1 , and its capacity loss per cycle is 0. 05% afrer being cycled 100 times.

关键词： thin films lithium manganese oxide lithium-ion battery solution deposition

Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of wuhan university of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 college of Resources & Environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 35 nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

Properties of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin liquid crystal Co and Ni complexes

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Science china chemistry 2007年第4期50卷 488-493页

作者： LIU Wei1,2.& SHI TongShun2.1 college of Materials Science and Engineering, Shandong university of Technology, Zibo 2.5049,{2. 2.Department of chemistry, Jilin university, Changchun 13002.,{2. 1. college of Materials Science and Engineering Shandong University of Technology Zibo 255049 China 2. Department of chemistry Jilin University Changchun 130023 China

Six series of meso-tetrakis (4-n-alkanoyloxyphenyl) porphyrin Co and Ni complexes (12.kinds) were reported. Nine of the compounds were found to exhibit liquid crystal properties and display a hexagonal columnar discotic columnar (Colh) phase. Molecular structure of all synthesized compounds was confirmed by IR, UV, MS, 1H NIVR, and elemental analysis. These liquid crystalline compounds have been studied by cyclic voltammetry, luminescence, and surface photovoltage spectroscopy.

关键词： porphyrin liquid crystal cyclic voltammetry luminescence surface photovoltage spectroscopy

Topological chirality and achirality of the closed circular DNAs

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Chinese Science Bulletin 1997年第20期42卷 1705-1708页

作者： QIU Wenyuan and XIN Houwen1. Department of Chemical Physics, university of Science and Technology of china, Hefei 2.002., china 2. Department of chemistry, Lanzhou university, Lanzhou 730000, china Depaitment of Chemical Physics University of Science and Technology of China Hefei 230026 China

THE study of the relations between the topological structure and its function is one of the focus-es in modern chemistry and life science. In this note we set up a topological model to de-scribe the ccDNAs on the basis of Seifert construction in knot theory. Our model for theccDNAs helps to determine whether a structure is topologically chiral or achiral. This is one ofthe fundamental biological problems.

关键词： DNA topology knot theory topologiesl chirality topological achirality.