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头孢噻肟钠在多壁碳纳米管修饰电极上的电化学行为及分析应用

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武汉大学学报（理学版） 2003年第2期49卷 157-161页

作者：吕少仿费俊杰孝感学院化学系湖北孝感432100 武汉大学化学与分子科学学院湖北武汉430072

提出了一种多壁碳纳米管化学修饰电极的制备方法 ,研究了头孢噻肟钠在该电极上的电化学行为及其测定 .头孢噻肟钠在多壁碳纳米管修饰电极上于 - 0 .85V处有一灵敏的还原峰 .将多壁碳纳米管修饰电极在 pH2..2.柠檬酸磷酸氢二钠缓冲溶... 详细信息

提出了一种多壁碳纳米管化学修饰电极的制备方法 ,研究了头孢噻肟钠在该电极上的电化学行为及其测定 .头孢噻肟钠在多壁碳纳米管修饰电极上于 - 0 .85V处有一灵敏的还原峰 .将多壁碳纳米管修饰电极在 pH2..2.柠檬酸磷酸氢二钠缓冲溶液中开路富集 2.in后 ,以 10 0mV·s-1的扫描速度从 - 0 .3～ - 1.1V进行阴极化扫描并测定 - 0 .85V处的还原峰电流 .该电流与头孢噻肟钠在 2..0× 10 -7～ 2..0× 10 -5mol·L-1浓度范围内呈良好的线性关系 ,检出限达 6.0× 10 -8mol·L-1(信噪比为 3 ) .

关键词：头孢噻肟钠化学修饰电极多壁碳纳米管电化学行为 β-内酰胺类抗生素测定方法

尖晶石锂锰氧化物中氧缺陷对材料电化学性能的影响

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武汉大学学报（理学版） 2003年第3期49卷 345-349页

作者：戴忠旭詹晖周运鸿桂嘉年王仁卉武汉大学物理科学与技术学院湖北武汉430072 武汉大学化学与分子科学学院湖北武汉430072

研究了富锂锂锰氧化物中氧缺陷对材料电化学性能的影响 .X射线衍射谱表明有氧缺陷的锂锰氧化物仍可保持尖晶石结构 ,当氧缺陷浓度达到一定程度时 ,高角度区的衍射峰出现分裂 ,说明其微观结构发生了变化 .充放电实验结果表明氧缺陷使 4V... 详细信息

研究了富锂锂锰氧化物中氧缺陷对材料电化学性能的影响 .X射线衍射谱表明有氧缺陷的锂锰氧化物仍可保持尖晶石结构 ,当氧缺陷浓度达到一定程度时 ,高角度区的衍射峰出现分裂 ,说明其微观结构发生了变化 .充放电实验结果表明氧缺陷使 4V区的锂离子嵌脱变成了多步 ,模拟电池的容量微分曲线有 3对清晰的氧化还原峰 ,低电位的氧化还原峰被一分为二 .氧缺陷降低了材料的放电容量 ,同时引起低电位区的放电容量向更低电位区转移 ,使电化学性能恶化 .锂锰氧化物中氧缺陷对电化学性能的影响对此类材料的合成提供了理论和实践依据 .

关键词：锂离子电池正极材料锂锰氧化物尖晶石结构氧缺陷电化学性能放电容量

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硫酸锰铵结晶水的测定及热分析

武汉大学学报（理学版） 2003年第6期49卷 685-688页

作者：宋力胡付欣李苹张克立信阳师范学院化学化工学院河南信阳464000 武汉大学化学与分子科学学院湖北武汉430072

合成了复盐硫酸锰铵,利用热重分析法(TG)、差示扫描量热法(DSC)、微商热重法(DTG)研究了它在氮气气氛中的热分解过程,确定了其结晶水的数目为7个,并通过Kay West方法确定了化合物热分解反应的活化能(E)、反应级数(n)和频率因子(A)等动... 详细信息

合成了复盐硫酸锰铵,利用热重分析法(TG)、差示扫描量热法(DSC)、微商热重法(DTG)研究了它在氮气气氛中的热分解过程,确定了其结晶水的数目为7个,并通过Kay West方法确定了化合物热分解反应的活化能(E)、反应级数(n)和频率因子(A)等动力学参数,用线性拟合的方法得到其相关系数均大于0.99,具有良好的动力学一致性,并运用等转化率法对热分析动力学参数进行了验证.

关键词：硫酸锰铵结晶水热分析动力学参数测定热重分析法差示扫描量热法微商热重法

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 wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

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

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

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 430072,{2. college of chemistry and molecular sciences, wuhan university, wuhan 430072,{2. wuhan Univ Coll Chem & Mol Sci Wuhan 430072 Peoples R China wuhan Univ Sch Med Electron Microscope Lab Wuhan 430072 Peoples R China

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

SOLUTION PROPERTIES OF ANTITUMOR CARBOXYMETHYLATED DERIVATIVES OF α-(1→3)-D-GLUCAN FROM GANODERMA LUCIDUM

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Chinese Journal of Polymer Science 2001年第3期19卷 283-289页

作者： Li-na Zhang Mei Zhang Jing-hua Chen Fan-bo Zeng Department of chemistry wuhan university,{2., china Pharmacy college, Tongji Medical university,{2., china wuhan Univ Dept Chem Wuhan 430072 Peoples R China Tongji Med Univ Coll Pharm Wuhan 430072 Peoples R China

Fractions of a water insoluble α-(1→3)-D-glucan (GL) extracted from Ganoderma lucidum were carboxy-methylated (CM) to obtain water-soluble carboxymethylated derivatives (CM-GL) having a degree of substitution (DS) of0.38～0.51. Weight-average molecular weight M_w and intrinsic viscosity [η] of the samples CM-GL were measured by gelpermeation chromatography combined with laser light scattering (GPC-LLS) and viscometry. The CM-GL exhibits a stifferchain in aqueous solution at 2.℃ than the original glucan, The antitumor activities against Ehrlich ascites carcinoma (EAC,5×10~6) of the carboxymethylated derivatives from the α-glucan and curdlan, a β-glucan, are significantly higher than thoseof the original glucans. The effects of the relatively low molecular weight, expanded chains and better water-solubility of theCM-GL on the enhancement of antitumor activity could not be neglected. The chain stiffness decreased speedily withincrease of temperature from 40 to 60℃ or NaOH concentration from 0.1 to 0.4 in the solution, respectively, and the changeof the chain stiffness is reversible.

关键词： Solution properties Antitumor activity Carboxymethylated derivative α-D-glucan Ganoderma lucidum

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 wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) hubei Agricultural college Department of Environmental Engineering Jingzhou Hubei China (GRID:grid.49470.3e) wuhan university College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

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