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111.
Carbon-coated monoclinic Li3V2(PO4)3 (LVP/C) cathode material has been successfully prepared by a novel glycine-assisted sol–gel method. The product is investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM) and electrochemical method. In the range of 3.0–4.3 V, the LVP/C electrode presents excellent rate capability. It is 125.4 mAh g− 1 that can be delivered at 1 C charge–discharge rate and 99.5 mAh g− 1 is still obtained at 20 C charge–discharge rate. These results demonstrate that the carbon-coated LVP/C composite material prepared via a glycine-assisted sol–gel method has great potential for use in high-power lithium ion batteries. 相似文献
112.
The unique catalytic activity of vanadium nitrogenase suggests a new direction for the direct production of biofuels from CO with either synthetic catalysts or nitrogenase-containing bacteria. The reduction of CO by V?nitrogenase to light hydrocarbons shows striking similarities to the established Fischer-Tropsch process; however, the enzyme does not use H(2) directly for this reaction. ADP=adenosine diphosphate, ATP= adenosine triphosphate. 相似文献
113.
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115.
Manuel Caetano Leonardo Padrino T Hector Gutiérrez Alberto J. Fernández Jimmy Castillo 《Mikrochimica acta》1998,128(3-4):169-175
Trace level vanadium determination is reported using a dual beam thermal lens spectrometer. The thermal lens was generated using an argon ion beam laser (pump beam) which was focused into a sample cuvette. The thermal lens signal (TLs) was monitored with a He-Ne laser beam and a photodiode detector. Multichannel averager software was developed for processing the transient TLs. The optimal set up, ensuring maximum sensitivity and linear calibration graphs was obtained using experimental design techniques. Under optimized conditions, the detection limits for aqueous and ethanol-water (2+3 v/v) and (4+1 v/v) vanadium complex solutions were, respectively, 0.0071 mg/l, 0.0065 and 0.0039 mg/l. 相似文献
116.
简要论述雾化提钒工艺完善提高中的数学建模与系统优化工作.由错综复杂的生产数据建立提高钒氧化率的数学规划模型,应用多种优选方法寻求各项工艺参数的最优控制范围及多因素的优化组合以改善指标值.在优化结果反馈指导生产实践过程中,追踪生产数据应用小子样统计推断理论,从钒氧化率的显著性差异以及流体力学上进行分析,找到了未知的关键影响因素.工艺参数的成功优化使得雾化提钒工艺得以完善提高,项目攻关取得了突破. 相似文献
117.
Yu. M. Smirnov 《Journal of Applied Spectroscopy》1995,62(6):996-1000
Moscow Power Engineering Institute, 14 Krasnokazarmennaya Str., Moscow, 105835, Russia. Translated from Zhurnal Prikladnoi
Spektroskopii, Vol. 62, No. 6, pp. 16–21, November–December, 1995. 相似文献
118.
Kharlamov A. I. Kirillova N. V. Kharlamova A. A. 《Theoretical and Experimental Chemistry》2002,38(6):357-362
It was found for the first time that carbon nanotubes are formed during the mechanical treatment of V2O5 powder in the presence of an organic solvent. The carbon content in the V2O5 sample, dispersed in alcohol, varies during milling and amounts to 2.1 wt.%. The unusually large increase in the catalytic activity of mechanically activated V2O5 in the selective oxidation of n-butane and also of benzene and propane is due to the formation of new active centers containing carbon inserted into the V2O5 structure. 相似文献
119.
本文采用装有Jones柱的流动注射系统,研究了钒(Ⅱ)-光泽精体系的化学发光反应。在此基础上建立了痕量钒测定的新方法。方法的检出限3×10 ̄(-10)g·mL ̄(-1);对于1.0×10 ̄(-7)g·mL ̄(-1)钒标准溶液测定的相对标准偏差为2%(n=11);线性范围1.0×10 ̄(-9)~9.0×10 ̄(-5)g·mL ̄(-1),相关系数大于0.9980。该方法已用于水样中痕量钒的测定。对于反应机理,本文也进行了探讨。 相似文献
120.
Amara Sif Eddine Kesri Rafika Valignat Nicole Hamar-Thibault Sylvaine 《Mikrochimica acta》1994,114(1):157-164
The solidification behaviour of Fe-V-C alloys, was studied by differential thermal analysis. The composition and the nature of the phases were analysed by quantitative electron probe microanalysis and X-ray diffraction. Accurate microanalysis of carbon in vanadium carbides (VCx and V2C) were performed. A liquidus projection of the system Fe-V-C in the Fe-V rich region was proposed. 相似文献