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Piezoelectric transmission spectroelectrochemistry with a normal piezoelectric quartz crystal as an optically-transparent electrode

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Chinese Journal of chemistry 1994年第5期12卷 425-431页

作者： XIE, Qing-Ji PANG, Xiao-Yong NIE, Li-Hua YAO, Shou-Zhuo Department of chemistry and chemical Engineering,{2., changsha, hunan 410082. China Department of chemistry and chemical Engineering Hunan University Changsha Hunan 410082 China

Piezoelectric transmission spectroelectrochemistry (PTSEC), i.e., the combination of electrochemistry and spectroelectrochemistry (SEC) with electrochemical quartz crystal microbalance (EQCM) technique is reported by using a normal piezoelectric quartz crystal (PQC) as an optically-transparent electrode (OTE). A theoretical relationship between the PQC response and the spectroelectrochemical response is derived and used to estimate the apparent molar absorptivity of the absorbing species deposited on the OTE on the PQC surface. The complex of copper with aspartic acid is used to test this new PQC-SEC technique. Results show that the combination of three such diverse techniques provides a very useful methodology for studying electrode processes and electrode surface characteristics in situ.

关键词： Piezoelectronic transimission spectroelectrochemistry optically-transparent electrode electrochemical quartz crystal microbalance copper aspartic acid.

Electrochemical characteristics of amorphous MgTi_xNi(x = 0,0.1,and 0.2. hydrogen storage alloys

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Rare Metals 2010年第5期29卷 486-490页

作者： LIU Suqin,ZHAO Wenjuan,HUANG Kelong,and HUANG Hongxia college of chemistry and {2. Engineering,Central South university,changsha 410083,China college of chemistry and {2. Engineering Central South University Changsha China

MgTixNi （x = 0, 0.1, and 0.2. alloys were successfully prepared by mechanical alloying （MA）, and the influence of milling time on the electrochemical characteristics of the electrodes was discussed. MgTixNi alloys after 90 h milling displayed the best electrochemical performance The X-ray diffraction patterns showed that the alloy ball-milled for 90 h was amorphous with a widened diffraction peak. The charge-discharge tests indicated that these alloys had good electrochemical activation properties, and the MgTi0.2.i alloy electrode exhibited the best cycle performance. The initial discharge capacity of the MgTi0.2.i alloy reached up to 401.1 mAh·g^-1, and the retention rate of capacity was 31.0% after 30 cycles, much higher than that of MgNi （17.3%）. The Tafel polarization curves revealed that Ti addition could enhance the anticorrosion performance of these alloys in alkali solution, which was responsible for the ameliorated cyclic stability of these alloy electrodes.

关键词： hydrogen storage alloys titanium electrochemical properties mechanical alloying

Preparation of Core-shell Cu-Ag Bimetallic Powder via Electroless Coating

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 637-639页

作者：徐锐 college of Metallurgy Science and Engineering Central South University college of chemical and Pharmaceutical Engineering Henan Universityof Science and Technology

A novel method of electroless silver coating on copper powders was reported, in which hydrazine was used as the reducing agent, and had some advantages such was used as inhibiting the substitution reaction and reducing consumption of copper powders. In the processes of sensitization and activation, AgNO3 replaces the conventional PdCl2. which solves the impurity of bath. Oxide film on the surface of copper powders was tested by chemical analysis. Ag element tested by XRD and XRF is in the form of Ago and exists on the surface of copper powders, which acts as catalyzer in reduction reaction. Morphology and composition of the coating were characterized by SEM and XRD respectively.

关键词： core-shell bimetallic powders electroless coating

Cell-SELEX-based aptamer-conjugated nanomaterials for enhanced targeting of cancer cells

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Science China chemistry 2011年第8期54卷 1218-1226页

作者： KONG RongMei, CHEN Zhuo, YE Mao, ZHANG XiaoBing & TAN WeiHong State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and {2. Engineering, hunan university, changsha 410082. China State Key Laboratory for Chemo/Biosensing and Chemometrics college of chemistry and {2. Engineering Hunan University Changsha China

Early detection and treatment of cancer depends on developing highly sensitive and specific methods for targeting cancer cells. To do this, aptamers, which are generated by a novel technique caUed ceU-SELEX （systematic evolution of ligands by exponential enrichment）, have been widely applied in cancer cell targeting based on such merits as high target affinity and specificity, small size, minimal immunogenicity, and ease of chemical modification. Furthermore, aptamers can gain more flexibility as cancer cell targeting tools when conjugated to nanomaterials, including metallic nanoparticles, quantum dots, silica nanoparticles, and carbon nanomaterials, among others. In this review, we discuss the use of cell-SELEX-based aptamer-nanomaterials conjugates as novel molecular tools for enhanced targeting of cancer cells.

关键词： celI-SELEX aptamer nanomaterial cancer cells targeting

^(99)Ru and ^(13)C-NMR Spectra for the Tris Chelates of 5-Substituted 1,10-Phenanthrolines with Ruthenium (Ⅱ)

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Chinese chemical Letters 1998年第8期9卷 765-766页

作者： Xiao Ming XIAO and Takeko MATSUMURA-INO UE2.Department of chemistry, hunan Normal {2., changsha, 410081)(Department of chemistry, Nara {2. of Education, Nara 63O, Japan) Department of chemistry Hunan Normal University Changsha 410081 China Department of chemistry Nara University of Education Nara 630 Japan

13C and 99Ru-NMR chendcal shifts are reported for the ruthenium(II) tris complexes of5-substitUted 1,10-phenanthrolines. It has been found that both of them are affected by the substituents on the phenanthrolines in a... 详细信息

关键词： NMR spectrum ruthenium(Ⅱ) complex substituent effect

Applying flexible molecular docking to simulate protein retention behavior in hydrophobic interaction chromatography

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Science China chemistry 2007年第5期50卷 675-682页

作者： ZHOU Peng1, TIAN FeiFei1 & LI ZhiLiang1,2.1 college of chemistry and {2. Engineering, Chongqing university, Chongqing 400044, China 2.State Key Laboratory of Chemo/Biosensing and Chemometrics, changsha 410082. China college of chemistry and {2. Engineering Chongqing University Chongqing China State Key Laboratory of Chemo/Biosensing and Chemometrics Changsha China

Interaction between proteins and stationary phase in hydrophobic interaction chromatography (HIC) is differentiated into two thermodynamic processes involving direct nonbonding/conformation interac- tion and surface hydrophobic effect of proteins, hence quantitatively giving rise to a binary linear rela- tion between HIC retention time (RT) at concentrated salting liquid and ligand-protein binding free en- ergy. Then, possible binding manners for 2. proteins of known crystal structures with hydrophobic ligands are simulated and analyzed via ICM flexible molecular docking and genetic algorithm, with re- sults greatly consistent with experimental values. By investigation, it is confirmed local hydrophobic effects of proteins and nonbinding/conformation interaction between ligand and protein both notably influence HIC chromatogram retention behaviors, mainly focusing on exposed portions on the protein surface.

关键词： hydrophobic interaction chromatography, flexible molecular docking, genetic algorithm, protein, salting-in factor

Cycloaddition mechanism for the resin-OsO_4-catalyzed of styrene: A DFT study

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Science China chemistry 2008年第1期51卷 19-24页

作者： ZHANG XingHui1, WANG KeTai1 & FANG Ran2.1 college of chemical Engineering, Gansu Unite {2., Lanzhou 730000, China 2.college of chemistry and chemical Engineering, Sun Yat-sen {2., Guangzhou 5102.5, China college of chemical Engineering Gansu Unite University Lanzhou China college of chemistry and {2. Engineering Sun Yat-sen University Guangzhou China

The postulated intermediates in the base-free and base-assisted addition of OsO4 to styrene have been investigated at the B3LYP/6-311G** level of the theory. N(CH3)2.Ph) was chosen as the base of the resin-OsO4. According to our model calculations the [2.3] addition was found to be favorable with an activation of 2.2. cycloaddition remain high (>155.00 kJ/mol). In addition, the electronic structure analysis of the molecules was carried out by na- ture bond orbital (NBO). The computational results were in reasonable agreement with experimental results.

关键词： cycloaddition resin-OsO4 density functional theory

Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science China chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. college of chemistry & Environment Protection Engineering, Southwest {2. for Nationalities, Chengdu 610041, China 2. TH-UNIS Insight Co., Ltd., Beijing 100085, China 3. Key Laboratory of Bioorganic Phosphorus chemistry & chemical Biology, Ministry of Education, Department of chemistry, Tsinghua {2., Beijing 100084, China college of chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu China TH-UNIS Insight Co. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus chemistry & chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Development of novel and sensitive sensors based on microcantilever of atomic force microscope

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Progress in Natural Science:Materials International 2006年第5期16卷 445-451页

作者： JIN Yan, WANG Kemin and JIN Rong (State Key Laboratory of Chemo/Biosensing and Chernometrics, Institute of Biological Technology, college of chemistry and {2. Engineering, hunan university, changsha 410082. China) State Key Laboratory of Chemo/Biosensing and Chemometrics Institute of Biological Technology College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

Recently, the development of sensors based on microfabricated cantilevers of atomic force microscope (AFM) has attracted considerable attention from the designers of novel physical, chemical, and biological sensors. Many kinds of sensors have been developed taking the advantages of its high-resolution imaging, force measurement and force sensitivity, such as immunosensor and DNA biosensor and the sensors for detection of intermolecular interaction. This paper reviews the progress made in this field and discusses the signal transfer principles by which the design of the sensors is achieved.

关键词： atomic force microscopy microcantilever sensor.