Surface solid-state interactions in copper-nickel-cement catalysts for hydrogenation of oxygen

The surface phase composition of alumocalcium cement-supported CuO and CuO-NiO catalysts prepared by chemical mixing has been studied using the method of thermo-vacuum curves of electric conductivity. The deactivation of these catalysts due to overheating to 800 °C under conditions of hydrogenation of oxygen is rationalized by the partial extraction of CuO (and NiO) from the stabilizing structure of the support solid solutions and by sintering of the extracted oxides and the reduced metallic phase. Complete regeneration of the CuO-NiO-talum catalysts can be achieved if a considerable amount (20%) of copper hydroxocarbonate is added.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1559–1562, September, 1994.     

微机控制离子色谱仪自动操作与数据处理系统

用转换器和ＩＢＭＰＣ／ＸＴ微机与Ｄｉｏｎｅｘ２０２０ｉ型离子色谱仪连接组成自动控制与数据处理系统，转换器由８０３１及８２５５等芯片组成，其功能是采集数据和转送数据，软件由汇编及Ｃ语言编制。这套新系统增加了注入／记录同步，分级梯度淋洗，自动连续进样等功能以及很强的数据处理能力。     

安培检测芯片毛细管电泳及其初步应用

An end-channel amperometric detector with a guide tube for working electrode was designed and integrated on a home-made glass microchip. The guide tube was directly patterned and fabricated at the end of the detection reservoir, which made the fixation and alignment of working electrode relatively easy. The fabrication was carried out in a two-step etching process. A 30 μm carbon fiber microdisk electrode and Pt cathode were also integrated onto the amperometric detector. The baseline separation of dopamine (DA), catechol (CA) and epinephrine (EP) was achieved within 80 s. Relative standard deviations of not more than 5.2% were obtained for both peak currents and migration times of DA and CA (n=5). Using standard adding method, DA in tLrine and plasma samples was detected. The recoveries were in the range of 83%—103%.     

Effect of Oxygen Redistribution on the Normal and Superconducting Properties of Yttrium High‐Temperature Superconductors

An anomaly is found in the vicinity of T_max 560$ K on electric resistance versus temperature curves for yttrium hightemperature superconductors of the 123 phase. Xray phase analysis suggests a structural phase transition in the vicinity of T_max due to oxygen redistribution in the mobile sublattice of this compound. Investigation of samples with Y partially replaced by Ca has shown that the structural phase transition does not depend on carrier concentration in the conduction band.     

碱性溶液中金电极上氧还原中间物研究

应用改进了的旋转全电极上的电势阶跃计时库仑法,分别测定了不同电极电势下氧还原过程中电极吸附中间物和溶解中间物氧化所需的电量,实验证明,在此过程中电极上确有吸附中间物存在,而且是电极电势的函数,但其分子属性尚需进一步鉴别。     

Electric parameters of photosystem II particles — electric light scattering study

Electric light scattering and microelectrophoresis were applied to investigate the electric moments (permanent dipole moment and electric polarizability and electrophoretic mobility of envelope-free chloroplasts and photosystem II (PS II particles. The effect of the removal of the extrinsic polypeptides (18, 24 and 33 kDa) on the electric moments was also studied. A significant difference was observed between the orientation behaviour of chloroplasts and PS II preparations. The data indicate that the permanent and induced dipole moments contribute to the orientation of the PS II particles, whereas chloroplasts possess induced dipole moment only.

NaCl and Tris treatments of PS II preparations influence both the transverse permanent dipole moment and the electric polarizability of PS II particles. The increase in the electrophoretic mobility of PS II particles on removal of the extrinsic proteins corresponds to an increase in the electric polarizability value, demonstrating its interfacial nature.     

Transport of glycine in systems with cation-exchange membranes in hydrochloric acid solutions: Effect of a heterogeneous protonation reaction

The electrical mass transfer of cations in electromembrane systems (EMS) with an MK-40 cation-exchange membrane and glycine in aqueous solutions of hydrochloric acid is studied using the method of a rotating membrane disk. Limiting current densities and limiting steps of the transport of cations in such systems are determined. Shown is the possibility of an increase in the electrical mass transfer of glycine as a consequence of the occurrence of a heterogeneous reaction of protonation of its zwitterions. The effect of the membrane surface state on the kinetic regularities of transport of cations in EMS with glycine in solutions of hydrochloric acid is exposed.     

W／O型微乳液活化能和导电机理研究

电导行为是微乳液的重要性质之一。自Lagourette和Lagues发现了W/O型微乳液电导渗透(Percolation)现象后,人们开始了微乳液导电机理的研究。较流行的观点认为,界面层中表面活性剂分子的阴离子在微乳颗粒碰撞时发生跃迁而使W/O型微乳液具有导电性。     

Structure and Electric Conductivity of (La,Sr)(Ga,Mg)O3-α Solid Electrolyte

Electric conductivity, Raman spectra, and thermal expansion of La_0.88Sr_0.12Ga_0.82Mg_0.18O_2.85 solid solution (LSGM1218) based on lanthanum gallate were studied at various temperatures, and Xray phase analysis was performed at room temperature. Dilatometric measurements showed that secondorder phase transitions occur at 775±10$ and 880± 20 K. The transition around 880 K is confirmed by Raman spectra and by a change in the conductivity activation energy in this temperature range. This transition is associated with a symmetry change in the oxygen sublattice.     

Moment characterization of localized orbitals

The parallel between orbital first and second electric moments and statistical first and second central moments is noted. Three measures of orbital spatial distribution in terms of their moments are proposed, and applied to the LMO's in a series of ten-electron hydrides. Consistent differences between bond and lone pair distributions are found. Using the statistical interpretation, for each LMO an effective solid angle around the central atom is postulated.