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Sensitive Determination of DNA by RLS Enhancement of Metal Ions

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wuhan University Journal of Natural sciences 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 43.072. 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

Surface modification of γ-Al_2._3 by sodium ions

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Chinese Science Bulletin 2001年第3期46卷 188-193页

作者： DENG Feng, YUE Yong, DU Youru, YE Chaohui, KONG Yuhua, WANG Guoxing & LI Xiaoding1. Laboratory of Magnetic Resonance and Atomic and molecular Physics, wuhan Institute of Physics and Mathematics, Chinese Academy of {2., wuhan 430071, china 2. hubei Institute of chemistry, wuhan 430074, china Laboratory of Magnetic Resonance and Atomic and molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China hubei Institute of chemistry Wuhan China

1H/2.Na double resonance NMR techniques were employed to study the modification of surface hydroxyls on Y-Al2.3 by sodium ions. 1H-2.Na cross polarization (CP) experiment can resolve three kinds of sodium cations that are closely associated with surface hydroxyl groups, while the signal of deposited salt-Na2.O3, which is not connected to surface hydroxyl groups, is completely suppressed. 1H{2.Na} spin echo double resonance experiments reveal the surface modification in more detail. At low Na+ coverage (5%, 10%), the acidic hydroxyl groups are preferentially coordinated with sodium ions, while both the acidic and the basic hydroxyl groups are accessible for sodium ions at highcoordination that causes proton of the OH groups to be easily dissolved, which is evidenced by the fact that with calcination temperature of the catalysts increasing, the acidic hydroxyl groups are preferentially removed and only the basic hydroxyl groups remain when the calcination temperature is raised to 600℃.

关键词： surface modification γ-Al2.3 NMR hydrodesulfu-rization catalyst.

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 china Univ Geosci Fac Earth Sci Wuhan 430074 Peoples R China S Cent Univ National Coll Chem & Life Sci Wuhan 430074 Peoples R 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.

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

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 sciences 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 43.072. 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

Correlation between the Standard Formation Enth alpy and the Path Index of Pyridine Derivatives

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wuhan University Journal of Natural sciences 2000年第2期5卷 229-232页

作者： LI Liang chao 1 ,LIAO Gui ying 1,2.,JIANG Sheng bin 2.,WANG Ying xi 2.,SUN Ju tang 3 1. Departmnt of chemistry, Jingzhou Normal college, Jingzhou,{2., 434100 2. hubei, Research Institute of chemistry, wuhan,{2., 430074 Jingzhou Normal college Department of Chemistry Jingzhou China Jingzhou Normal college Department of Chemistry Jingzhou China hubei Research Institute of Chemistry Wuhan China hubei Research Institute of Chemistry Wuhan China wuhan University College of Chemistry Wuhan China (GRID:grid.49470.3e) (ISNI:***)

A formulated as △fH m ? (PPDs,g)=a+ΣbiPi + cifi is put forward for estimating standard formation enthalpies of pyridine-derivatives (PDDs), in which,P i is path index andc i f i is an amended term of interaction between substituent and N atom on pyridine ring. The Calculations based on the model were carried out for some pyridine-derivatives. The values of standard formation enthalpy calculated are consistent with those in literature.

关键词： Key words pyridine derivatives standard formation enthalpy path index

Electrochemical Studies of Glutathione Monolayer Assembled on A Polycrystalline Gold Electrode

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wuhan University Journal of Natural sciences 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 43.072. 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

A thin-layer spectroelectrochemical study of 3,3',5,5'-tetramethylbenzidine at SnO_2.F film optically transparent electrode

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Science china chemistry 2004年第4期47卷 267-275页

作者： JIAO Kui1, YANG Tao2.& NIU Shuyan1,2.1. college of chemistry and {2. Engineering, Qingdao University of Science and Technology, Qingdao 2.6042. china 2. college of chemistry and Chemical Engineering, Ocean University of china, Qingdao 2.6003, china Correspondence should be addressed to Jiao Kui 1. college of chemistry and {2. Engineering Qingdao University of Science and Technology 266042 Qingdao China 2. college of chemistry and Chemical Engineering Ocean University of China 266003 Qingdao China

The electrooxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) is dependent on the pH value of Britton-Robinson (B-R) buffer solution. In this work, the electrooxidation behavior of TMB was investigated with a SnO2.F film optically transparent thin-layer spectroelectrochemical cell. TMB underwent one two-electron electrooxidation process in the pH range from 2.0 to < 4.0, and two successive one-electron electrooxidation processes in the pH range from 4.0 to < 7.0 in the B-R buffer solution. At pH 6.5, the electrooxidative product of TMB generated a subsequent chemical reaction to yield an azo compound. Several spectroelectrochemical techniques, such as thin-layer cyclic voltammetry, thin-layer cyclic voltabsorptometry, thin-layer potential-controlled electrolysis absorptometry, thin-layer single-potential-step chronoabsorptometry, thin-layer dou-ble-potential-step chronoabsorptometry, thin-layer single-potential-step open-circuit relaxation chronoabsorptometry, were applied to this investigation. The formal potential E0’ and the electron transfer number corresponding to the electrooxidation of TMB in B-R buffer solution, and the reaction rate constant of the subsequent chemical reaction were determined.

关键词： 3,3′,5,5′-tetramethylbenzidine tin oxide film optically transparent electrode thin-layer spectroelectro-chemistry electrooxidation

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