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71.
对NO生理作用的新认识及其电化学实时检测 总被引:8,自引:0,他引:8
本文综述了近年来学术界对NO生理作用的新认识,并介绍了现场实时检测生物活体中释放的NO浓度的电化学方法. 相似文献
72.
73.
尖晶石锂锰氧化物锂离子嵌脱过程的交流阻抗谱研究 总被引:18,自引:1,他引:18
用粉末微电极研究了尖晶石锂锰氧化物在不同嵌锂状态下嵌脱锂过程的交流阻 抗图谱,提出了新的等效电路模型。描述锂离子在固体中扩散的Warburg阻抗与累 积或消耗的嵌入电容在Lix MnO4中的x≤0.5时串联,0.5<x≤1时并联。用提出 的等效电路模型分阶段拟合了实验所得的交流阻抗谱,拟合值与实验值相当吻合, 由拟合结果得到不同电位下锂离子在表面膜中的迁移电阻和电容,界面电荷传递电 阻,双层电容,锂离子在固体中扩散系数和累积或消耗的嵌入电容。 相似文献
74.
75.
Kinetic equations for a multistage electrode process complicated by the transfer of intermediates between the near-electrode layer and bulk solution are derived and analyzed. Computer-aided modeling of the kinetics of processes of this kind is performed. Conditions under which the share of diffused intermediates is no longer vanishingly small are determined. Effect of various factors on the individual stages is established. Techniques of processing experimental data for determining kinetic parameters of separate stages are suggested. 相似文献
76.
Summary This paper reports the results of a study on the use of a new polymer-based, strong anion-exchange, stationary phase for rapid
and selective separation of carbohydrates and related compounds by high-pH, anion-exchange chromatography with pulsed amperometric
detection. The new adsorbent has been obtained by direct nitration of 2.8 μm, spherical non-porous highly cross-linked, styrene-divinylbenzene
copolymer beads, followed by reduction of superficially introduced nitro groups with nascent hydrogen and quaternization of
the resultant amino groups with iodomethane. It is reported that by optimizing the ionic strength of the mobile phase, columns
packed with the new anion-exchanger can be successfully employed to separate, either in isocratic or gradient elution mode,
oligosaccharides, positional isomers of gluco-disaccharides, as well as uronic acids and sugar monophosphates. 相似文献
77.
R. D. Rakhimov E. R. Milaeva O. V. Polyakova K. P. Butin 《Russian Chemical Bulletin》1994,43(2):289-292
A procedure for the alkylation of metallic mercury by (dimethylglyoximato)butylcobalt(III) electrochemically generated in the presence of butyl bromide is proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 309–312, February, 1994. 相似文献
78.
Titanium dioxide (TiO2) thin films have been prepared on indium doped tin oxide (ITO) glass by sol-gel dip-coating method. Properties of the films
were determined as a function of heat-treatment by X-ray diffraction, scanning electron microscopy and photoelectrochemical
tests. The films heat-treated at higher temperatures show better crystallinity and photoresponse. The microscopic structure
on the film after heat-treatment is attributed to the incorporation of organic polymer into the precursor solution. The performance
of the electrodes treated at different temperature on photoelectrocatalytic degradation of methyl orange was investigated.
The effect of applied potential and the ability of the electrode to be repeatedly used in photoelectrocatalytic degradation
were also evaluated. 相似文献
79.
Summary Four different techniques to quantify unresolved chromatographic peaks with known spectral features combined with photodiode array detection, are investigated as regards their efficiency for the accurate and precise determination of drugs in the low g-range. The comparison includes peak suppression utilising difference chromatograms, first-order derivative chromatograms, selective chromatograms, generated by the calculation of orthogonal polynomial shares, and the powerful least-squares multicomponent analysis approach. Each of these methods uses UV-spectra taken throughout, the peak. The results presented and conclusions reached should enable the chromatographer to come to a decision about the reasonable use of these options now provided by multichannel detection in HPLC. 相似文献
80.
M. V. Reddy B. Pecquenard P. Vinatier A. Levasseur 《Surface and interface analysis : SIA》2007,39(8):653-659
We prepared stoichiometric lithium nickel vanadate amorphous thin films by using r.f. magnetron sputtering under controlled oxygen partial pressure. The amorphous films were heated at various temperatures, 300–600 °C, for 8 h. The as‐deposited and annealed thin films were characterized by Rutherford backscattering spectroscopy, nuclear reaction analysis, Auger electron spectroscopy, X‐ray diffraction, scanning electron microscopy and atomic force microscopy. The electrochemical behavior of the various films was studied by the galvanostatic method. The cells were tested in a liquid electrolyte at room temperature, with lithium metal used as the counter and reference electrode. The best electrochemical storage value was obtained with the thin film annealed at 300 °C, which showed superior capacity and small capacity loss during cycling. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献