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61.
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
62.
The effect of pressure during thermal plasma chemical vapor deposition of diamond films has been investigated for a pressure range from 100 to 760 Torr. The maximum growth rate in our experiments occurs at 270 Torr for substrate temperatures around 1000°C. The existence of an optimum pressure for diamond deposition may he related to the balance between generation and recombination of atomic hydrogen and carbon-containing active species in front of the substrate. To estimate the concentrations of atomic hydrogen and methyl radicals under thermal plasma conditions, calculations based on thermodynamic equilibrium have been performed. This approximate evaluation provides useful guidelines because rapid diffusion results in a near frozen chemistry within the boundary layer. The effect of substrate pretreatment on diamond deposition depends on the type of substrate used. Two growth modes have been observed-layer growth and island growth of diamond crystals on various substrates. Screw dislocations have been observed in diamond deposition in thermal plasmas, and defects such as secondary nucleations are more concentrated along (III) directions than along (100) directions. 相似文献
63.
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
64.
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
65.
Yang J Bos R Belder GF Engel J Busscher HJ 《Journal of colloid and interface science》1999,220(2):410-418
The aim of this paper is to determine to what extent (i) deposition of oral bacteria and polystyrene particles, (ii) onto quartz and dental enamel with and without a salivary conditioning film, (iii) in a parallel plate (PP) and stagnation point (SP) flow chamber and at common Peclet numbers are comparable. All three bacterial strains showed different adhesion behaviors, and even Streptococcus mitis BMS, possessing a similar cell surface hydrophobicity as polystyrene particles, did not mimic polystyrene particles in its adhesion behavior, possibly as a result of the more negative ζ potentials of the polystyrene particles. The stationary endpoint adhesion of all strains, including polystyrene particles, was lower in the presence of a salivary conditioning film, while also desorption probabilities under flow were higher in the presence of a conditioning film than in its absence. Deposition onto quartz and enamel surfaces was different, but without a consistent trend valid for all strains and polystyrene particles. It is concluded that differences in experimental results exist, and the process of bacterial deposition to enamel surfaces cannot be modeled by using polystyrene particles and quartz collector surfaces. 相似文献
66.
单斜层状LiMnO2的球磨-离子交换法合成及其电化学性能研究 总被引:2,自引:0,他引:2
通过球磨促进固相反应法合成出了具有单斜层状结构的前驱物NaMnO2,随后通过离子交换得到了单斜层状LiMnO2。XRD测试结果显示产物为单相。扫描电镜(SEM)和透射电镜(TEM)观测结果显示LiMnO2的粒子尺寸为300~500 nm,HRTEM分析显示干扰条纹的间距为0.485 nm,基本对应于m-LiMnO2的(001)晶面间距。红外吸收光谱(IR)和X射线光电子能谱(XPS)被用来测量m-LiMnO2中Mn-O键的伸缩和弯曲振动吸收和Mn元素的价态。合成的m-LiMnO2在电化学充放电循环初期表现了较好的电化学性能,但其循环寿命仍需要进一步改善。 相似文献
67.
68.
69.
One novel complex [Co(p-MBA)2(2,2'-bipy)(H2O)]·(H2O) has been synthesized by the reaction of p-methylbenzoic acid with 2,2'-bipyridine in the solvent mixture of water and methanol. It crystallizes in triclinic, space group P-1 with a=0.70479(14), b=1.1211(2), c=1.6718(3) nm, α=103.806(3), β=90.795(3), γ=104.207(3)°, V=1.2399(4) nm3, Mr=512.41, Dc=1.373 g/cm3, Z=2, F(000)=532, μ=0.733 mm-1, R=0.0432 and wR=0.0957. The crystal structural analysis shows that the cobalt atom is coordinated with three oxygen atoms from two p-methylbenzoic acids and one water molecule and two nitrogen atoms from one 2,2'-bipyridine,forming a distorted square-pyramidal coordination geometry. The cyclic voltammetry behavior of the complex is also reported. 相似文献
70.
微乳液法合成LiFePO4 / C正极材料及其电化学性能 总被引:4,自引:0,他引:4
本文采用微乳液方法合成了纳米LiFePO4 / C正极材料。制备样品分别用XRD和SEM进行表征,充放电测试其电化学性能。600 ℃制备样品为单一物相,平均粒径90 nm,在室温2.0~4.0 V (vs Li) 放电电压范围和15 mA·g-1放电速率下,首次放电容量达到159 mAh·g-1。制备样品同样展现良好的循环性能。在15 mA·g-1速率下40次循环后,制备样品放电容量仍保持首次放电容量的98.9%。优异的电化学性能得益于样品颗粒的纳米尺寸、均匀分布以及表面碳层包覆提高了活性材料的电子电导率。 相似文献