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31.
低共熔混合锂盐相图的绘制及应用 总被引:3,自引:0,他引:3
采用热分析法对不同组成的混合锂盐二元体系进行研究, 绘制了混合锂盐体系的步冷曲线和T-x相图, 结果表明体系均为具有最低共熔点的二元体系. LiOH-LiNO3、LiOH-LiCl、LiOH-Li2CO3及LiNO3-LiCl体系的最低共熔点分别为175.7、294.5、418.2及221.6 ℃. 利用低共熔混合物LiNO3-LiOH为锂盐与不同前驱体反应, 制备出了层状结构良好的锂离子电池正极材料LiNiO2、LiNi0.8Co0.2O2及LiNi1/3Co1/3Mn1/3O2. X射线衍射分析表明, 合成的材料具有规整的层状NaFeO2结构, 且XRD衍射峰强度之比I(003)/I(104)>2.0, 电性能测试表明, 在2.7-4.3 V(vs Li/Li+)的电压范围内进行0.1C倍率充放电, LiNiO2、LiNi0.8Co0.2O2、LiNi1/3Co1/3Mn1/3O2首次充电比容量分别达168.0、225.4、194.0 mAh·g-1, 放电比容量分别为138.4、165.8、157.7 mAh·g-1. 相似文献
32.
A. V. Kazakova N. D. Kushch L. I. Buravov E. B. Yagubskii S. V. Simonov L. V. Zorina S. S. Khasanov R. P. Shibaeva E. Canadell J. Yamada M. Umemiya 《Russian Chemical Bulletin》2007,56(1):49-55
New radical cation salts based on 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP) with copper(II) metal complex anions, β-(BDA-TTP)4Cu2Cl6 and (BDA-TTP)2CuCl4, were synthesized and structurally characterized. Single crystals were prepared by electrochemical oxidation of BDA-TTP under
galvanostatic conditions. X-ray diffraction study demonstrated that the salts have a layered structure, in which the conducting
BDA-TTP layers alternate with the [Cu2Cl6]2− or [CuCl4]2− anions. Both salts show the semiconductor-type temperature dependence of the conductivity.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 48–54, January, 2007. 相似文献
33.
Tadatomi Nishikubo Atsushi Kameyama Jun Yamashita Masao Tomoi Wakichi Fukuda 《Journal of polymer science. Part A, Polymer chemistry》1993,31(4):939-947
The addition reaction of oxiranes ( 26a—e ) with carbon dioxide (CO2) was performed using insoluble polystyrene beads containing pendant quaternary ammonium or phosphonium salts as catalysts under atmospheric pressure. The reaction of 26a—e with CO2 proceeded smoothly catalyzed by 1–2 mol % of the polymer-supported quaternary onium salts to give the corresponding cyclic carbonates ( 27a—e ) in high yields at 80–90°C. In this reaction system, the catalytic activity of the polymer-supported quaternary onium salts was strongly affected by the following factors: degree of ring substitution (DRS) of the onium salt residues to the polymer, degree of crosslinking (DC) of the polystyrene beads, chain length of the alkylene spacer between the polymer back-bone and the onium salt, hydrophobicity of the alkyl group on the onium salts, and kind of onium salts. That is, the polymer-supported quaternary phosphonium salts with low DRS and DC and with long alkylene spacer chain were found to have higher catalytic activity than low molecualr weight quaternary onium salts. The above polymer-supported catalysts can easily be separated at the end of a reaction by filtration and can be reused for at least seven runs. It was also found that the rate of reaction was proportional to the products of catalyst concentration and oxirane concentration. © 1993 John Wiley & Sons, Inc. 相似文献
34.
S.V. Devyatkin 《Journal of solid state chemistry》2004,177(2):407-409
Powder and coatings of metal-like refractory compounds (MLRC) can be produced by electrochemical synthesis from molten salts. The stoichiometry of the deposited MLRC was found to correlate with the molar ratio of MLRC component ions in the melts. The system Ti-Si-B is of particular interest in terms of electrochemical synthesis since the titanium, silicon and boron potentials in the melt are close together. The electrochemical synthesis has been investigated in the system NaCl-KCl-NaF-K2TiF6-K2SiF6-KBF4 at 700°C. The opportunity of deposition of new ternary compound in the system Ti-Si-B is shown by the electrochemical synthesis from molten salts. 相似文献
35.
Kazuhiro Kobayashi Atsushi Takanohashi Kenichi Hashimoto Osamu Morikawa Hisatoshi Konishi 《Tetrahedron》2006,62(44):10379-10382
A facile synthetic method for 4,5-diaminopyrrolo[1,2-a]quinoline derivatives has been developed. Treatment of 2-(pyrrol-1-yl)benzaldehydes with secondary amine hydrochloride/NaI/TMSCl/Et3N in the presence of an isocyano compound leads to the formation of 4-alkyl(or aryl)amino-5-dialkylaminopyrrolo[1,2-a]quinolines. 相似文献
36.
37.
氯化1-乙基-3-甲基烷基咪唑分子结构及其氢键作用能的密度泛函研究 总被引:1,自引:0,他引:1
采用量子化学密度范函方法计算研究了氯化1-乙基-3-甲基咪唑盐([EMIM]C1)正负离子间相互作用的平衡构型和Cl^-离子从不同方位与咪唑阳离子的结合能.计算发现Cl^-可在咪唑环平面上结合形成离子键,其结合能为.368.97kJ/mol,还可与环上的三个H原子形成氢键,其氢键键长和结合能分别为0.2000nm/-378.03kJ/mol、0.2339nm/-344,69kJ/mol和0.2301nm/-346,01kJ/mol.结合能包括氢键作用能和正负离子的静电作用能,后者为主要贡献.从理论上展示了该离子液体的氢键结构. 相似文献
38.
Sofiane Ben Hamouda Quang Trong Nguyen Pierre Schaetzel 《European Polymer Journal》2006,42(11):2994-3005
Ethylene/ethane sorption characteristics were determined for dry Pebax™ (poly(amide 12-block-tetramethylenoxide) copolymer)/AgBF4 membranes by using an electronic microbalance. The membranes containing 0.7 and 22 wt.% AgBF4 showed a dual-mode sorption isotherm. The ethane isotherms for all the membranes were of the Henry-type, which is the normal sorption for gases in rubbery polymers. The abnormal presence of Langmuir sorption sites only for ethylene in the rubbery copolymer, never reported sofar, is attributed to the silver-based specific complexation sites. The silver salt which dissolved in limited amounts in the rubbery copolymer had a much smaller Langmuir sorption capacity than the salt that crystallized in the copolymer. The sorption kinetics indicate that the crystallized salt did adsorb slowly ethylene according to a zeroth-order kinetics, but not ethane. The gas uptake kinetics resulting from a step of the pressure surrounding the copolymer exhibited one stage for ethane but two stages for ethylene. For the latter, there was first a fast Fickian sorption stage, then a drift of the zeroth-order sorption of ethylene on salt crystals, which contributes for a large part to the total uptake. The zeroth-order sorption suggests that the sorbed ethylene amount in the second-stage is independent of the crystal-surface coverage. The value of the Fickian diffusion coefficient calculated by fitting the kinetics with a solution of the second Fick’s law was 5 × 10−12 m2/s for both ethylene (the first stage) and ethane, and is typical for small organic compounds in a rubbery material. 相似文献
39.
40.
环氧丙烯酸酯的紫外光固化 总被引:8,自引:0,他引:8
制备了适于配制紫外光固化涂料的环氧丙烯酸酯,研究了反应温度、阻聚剂、催化剂等因素对环氧树脂与丙烯酸反应的影响;讨论了反应机理和动力学;并利用红外光谱观察了产物的紫外光固化行为。季铵盐能有效地催化环氧树脂和丙烯酸的反应,当其用量为0.6%~1.2%时,在90~110℃反应4.5~8小时后,环氧基转化率大于97%。由此配制的光固化涂料经紫外光辐照能快速固化。 相似文献