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A New PAA Sol-Gel Method to Synthesis the Spinel LiMn_2._4 Material for Li-ion Battery

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wuhan university Journal of Natural {2. 2002年第1期7卷 97-101页

作者： Zhan Hui, Zhou Yun-hong  college of chemistry and {2. sciences, wuhan university, wuhan 430072. hubei, China college of chemistry and Molec. Sci. Wuhan University Wuhan 430072 Hubei China

A PAA sol-gel method, which is based on the chelate effect of PAA polymer, was developed for the synthesis of the spinel LiMn 2. 4 material. The pyrolysis process of the PAA-nitrate mixture precursor was investigated by TG and DTA analysis. It is found that the structure and electrochemical properties of the material are sensitive to the atmosphere employed in the synthesis process. Preliminary results show that the material thus prepared has a good electrochemical performance even at high charge and discharge current.

关键词： sol-gel PAA spinel material

Electrochemical Studies of Glutathione Monolayer Assembled on A Polycrystalline Gold Electrode

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wuhan university Journal of Natural {2. 2002年第1期7卷 102-106页

作者： Fang Cheng, Zhou Xing-yao  college of chemistry and {2. sciences, wuhan university, wuhan 430072. hubei, China college of chemistry and {2. sciences Wuhan University Wuhan Hubei China

The glutathione (GSH) monolayer and complex monolayer of GSH-metallic ion on polycrystalline gold electrode were studied by using K3Fe(CN)6 as the redox probe. As for the GSH monolayer, it was found that the metallic ions could open the ion-gate in the monolayer dramatically in the order La3+> Pb2.>>Ba2.>Ca2. whereas Zn2. ion closed the ion-gate. The complexes of GSH-metallic ions were capable of self-assembling the different kind of monolayer. All the differences were related to the structural configuration of the anchored GSH molecule, which changed with different metallic ions or pH.

关键词： glutatione monolayer complex voltammetry and ac impedance

Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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wuhan university Journal of Natural {2. 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 {2. sciences, wuhan university, wuhan 430072. hubei, China 2. Department of Environmental Engineering, hubei Agricultural college, Jingzhou 43402., hubei, China college of chemistry and {2. 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 (2.2.502.) and the National Key Basic Research and Development Program (973 Program 2.02.B2.1800).Biography: Huang Jian-ping(1964-), male, Associate professor, research direction: bioanalysis.

关键词： resonance light scattering DNA metal ions

Infrared Spectroscopic and Theoretical Studies on Cobalt(Ⅱ) Complex of Maleinitriledithiolate and 4, 4′-Dimethyl-2. 2.-bipyridine

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wuhan university Journal of Natural {2. 2002年第1期7卷 87-96页

作者： Peng Zheng-he, Cai Ping, Fang Chen-jie, Wen Li-li college of chemistry and {2. sciences, wuhan university, wuhan 430072. hubei, China college of chemistry and {2. sciences Wuhan University Wuhan Hubei China

The complete experimental IR spectra and vibrational analysis of the title complex Co(mnt)(dmbpy) were reported in this paper. The results show that the complex molecule has a planar geometry belonging to point group C 2. and ground electronic state with spin quartet. A new method for analyzing vibrational spectra of complicated molecule is established. The essential of this method is to point out main fixed points and pivotal vibrational units in assignment for each fundamental band. Two new symbols η (heaving along the specified direction) and M (midpoint of a bond or unit) were defined for describing the vibrational modes accurately.

关键词： Cobalt(Ⅱ) complex infrared spectrum new method to analyze vibrational spectra quantum chemical calculation

MCM-41 Prepared with Ionic Liquid and Cethytrimethylammonium Bromide as Co-templates

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Journal of wuhan university of Technology(Materials Science) 2009年第1期24卷 25-29页

作者：张光旭 School of Chemical Engineering Wuhan University of Technology college of chemistry and {2. sciences Wuhan University

The mesoporous molecular sieves MCM-41 were prepared using room tempera-ture ionic liquid （RTIL） synthesized in laboratory and cethytrimethylammonium bromide （CTAB） as compound templates for the first time. They were prepared under low aging temperature and short aging time. Via characterizing by XRD and nitrogen adsorption instrument, MCM-41 synthesized by this new method exhibited good crystal structure and narrow pore distribution. The following pre-paratory conditions was optimal： the molar ratio of RTIL to CTAB was 1.0∶1.0, aging at 80 ℃, for 40 h and calcined at 540 ℃. It is found that the acidified MCM-41 improves its activity as catalyst over the unmodified ones.

关键词： mesoporous molecular sieve hydrothermal crystallization co-templates ionicliquid MCM-41

CHARACTERIZATION OF REGENERATED CELLULOSE MEMBRANES HYDROLYZED FROM CELLULOSE ACETATE

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Chinese Journal of Polymer Science 2002年第4期20卷 369-375页

作者： Yun Chen Xiao-peng Xiong Guang Yang Li-na Zhang Sen-lin Lei Hui Liang Electron Microscope Lab of Medical School, wuhan university wuhan {2. China college of chemistry and molecular sciences, wuhan university, wuhan {2. China Electron Microscope Lab of Medical School Wuhan University Wuhan 430072 college of chemistry and {2. sciences Wuhan University Wuhan 430072

A series of cellulose acetate membranes were prepared by using formamide as additive, and then were hydrolyzed in 4 wt% aqueous NaOH solution for 8 h to obtain regenerated cellulose membranes. The dependence of degree of substitution, structure, porous properties, solubility and thermal stability on hydrolysis time was studied by chemical titration, Fourier transform infrared spectroscopy, scanning electron microscopy, wide-angle X-ray diffraction, and differential scanning calorimetry, respectively. The results indicated that the pore size of the regenerated cellulose membranes was slightly smaller than that of cellulose acetate membrane, while solvent-resistance, crystallinity and thermostability were significantly improved. This work provides a simple way to prepare the porous cellulose membranes, which not only kept the good pore characteristics of cellulose acetate membranes, but also possessed solvent-resistance, high crystallinity and thermostability. Therefore, the application range of cellulose acetate membranes can be expanded.

关键词： hydrolysis cellulose acetate thermal stability regenerated cellulose membrane pore size solvent-resistance SEM

Surface Films Formed on SnO_2.Anode in Lithium Secondary Batteries by FTIR Spectroscopy

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Journal of wuhan university of Technology(Materials Science) 2008年第5期23卷 662-665页

作者：黄峰 hubei Refractories and High-temperature Ceramics Key Laboratory Wuhan University of Science and Technology

The chemical composition of the passivating layer formed on nano SnO2.anodes in 1 M LiClO4＋（ethylene carbonate）EC ＋（dimethyl carbonate）DMC at different charge/discharge states in lithium secondary batteries was studied using extra reflectance FTIR spectra. Results show that solvent decomposition reaction that generally occurs on the surface of carbon and alkali metal electrodes also takes place on nano-SnO2.anode, and the major constituent of the passivating layer is Li2.O3 and ROCO2.i. Formation of the passivating layer would certainly lead to the irreversible capacity loss.

关键词： nano-SnO2.anode lithium rechargeable batteries FTIR passivating layer

Permian carbonates of Baoshan block, Western Yunnan and their paleoclimatic implications

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Science China Earth sciences 2004年第5期47卷 385-392页

作者： YAN Jiaxin1, LIANG Dingyi1 & WU Ming2.1. Faculty of Earth sciences, China university of Geosciences, wuhan 430074, China 2. college of chemistry and Life sciences, South-Central university for Nationalities, wuhan 430074, China Faculty of Earth sciences China University of Geosciences Wuhan 430074 China college of chemistry/Life {2. South-Central Univ./Nationalities Wuhan 430074 China

Recently, much attention has been paid to the climatic significance of carbonates originating in shallow water. Permian carbonates of shallow shelf origin are present in the upper part of the Dingjiazhai Formation, the upper part of the Yongde Formation, and the Shazipo Formation on the Baoshan block of Western Yunnan. Their skeleton and non-skeleton grain as-sociations have been investigated in this study. The carbonates of the Dingjiazhai Formation indicate a Bryonoderm (bryozoans-echinoderm) association without non-skeleton grains. The carbonates of Yongde and Shazipo formations show Chloroforam (green algae-foraminifers) association with peloids. Oolites develop in the Shazipo Formation. Based on the comparisons of grain association with coeval carbonates formed in different paleolatitudes (i.e. various paleo-climatic zones), the carbonates of the Dingjiazhai Formation were thought to have been accu-mulated in shelf environments of warm-temperate zone, and those of the Yongde and Shazipo formations in shelf environments of warm-water.

关键词： Early Permian, carbonate, paleoclimate, Western Yunnan.

Spectrofluorimetric Method for the Determination of Triamcinolone Acetonide

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wuhan university Journal of Natural {2. 2004年第3期9卷 353-358页

作者： PanZu-ting YuJun-ping collegeofchemistryand{2.sciences WuhanUniversityWuhan430072HubeiChina

A simple and highly sensitive method for the determination of triamcinolone acetonide in pharmaceutical formulations is presented. The approach is based on the fluorescence of production of triamcinolone acetonide oxidized by concentrated sulfuric acid. The effect of H2.O4, β-cyclodextrin (β-CD), solvent and cetyltrimethylammonium bromide (CTMAB) were discussed. And two analytical systems were established. One is CTMAB system, the linear range is 0–4.6×10?6 mol/L, and the detection limit is 3.59×10?8 mol/L. The other is β-CD and ethanol system, the linear range is 0–2.3×10?6 mol/L and the detection limit is 1.91×10?8 mol/L. The selectivity of analysis, the analytical figures of optimization, and the accuracy of the method are demonstrated with the determination of triamcinolone acetonide in pharmaceutical preparations. Key words triamcinolone acetonide - fluorimetry - CTMAB - β-cyclodextrin - pharmaceutical analysis CLC number O 657.39 Foundation item: Supported by the National Natural Science Foundation of China (2.2.502.)Biography: Pan Zu-ting (1945-), male, Professor, research direction: analytical chemistry.

关键词： triamcinolone acetonide fluorimetry CTMAB β-cyclodextrin pharmaceutical analysis