Zr（Y）O2衬底上大面积YBCO薄膜表面组织状态的研究

使用配备有ＥＤＳ和ＥＣＰ附件的ＳＥＭ、ＡＥＭ、和ＳＴＭ研究在７５０和８００℃的Ｚｒ（Ｙ）Ｏ２衬底上磁控溅射沉积的大面积ＹＢＣＯ超导薄膜的表面组织。ＹＢＣＯ薄膜为ｃ轴取向单晶，但衬底温度为８００℃时，膜表面的突出组织多为ＣｕＯ颗粒，小坑较多，表面粗糙；衬底温度为７５０℃时，突出组织多为棒状和多边形１２３结构，很少小坑，表面较平整。     

KINETICS OF DEPOSITION OF METAL IONS TO ACTIVATED CARBON FIBERS (ACFs) WITH FLUIDIZATION

1. INTRODUCTION Study on the deposition of metal ions on ACFs indicated that such a process consists of several consecutive steps [1]: (1) transfer of the solvated ions (metal ions) from the bulk solution to the proximity of the ACFs surface; (2) absorpt…     

Molecular dynamics simulation of room-temperature ionic liquid mixture of [bmim][BF4] and acetonitrile by a refined force field

1-Butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) is one of the promising room-temperature ionic liquids. To test the refined force field for [bmim][BF4] proposed in our previously work (J. Phys. Chem. B, 2004, 108, 12978-12989), thermodynamic properties of mixtures of [bmim][BF4](1)+ acetonitrile (2) are presented by using molecular dynamics over the whole concentration range. The calculated densities are in good agreement with the experimental data with deviations less than 2%, indicating the force field is applicable to the mixtures. In addition, the diffusion constants, viscosities, heats of vaporization, cohesive energy densities and excess properties of the mixtures are reported. The microscopic structures are discussed in detail, corresponding to the thermodynamic properties.     

A new poly(2-hydroxy-3-phenoxypropylacrylate, 4-hydroxybutyl acrylate, diethyl maleate) membrane controlled clonidine linear release in the transdermal drug delivery system

Oral clonidine, used as an antihypertensive, can result in some side effects such as dry mouth, drowsiness, dizziness and sedation; thus, clonidine transdermal drug delivery (TDD) was considered. Use of the controlled release membrane was one of the methods in TDD systems to regulate the permeation properties. A new type of copolymer membrane that controlled clonidine linear release in TDD system was synthesized by UV radiation. This membrane consisted of three monomers: 2-hydroxy-3-phenoxypropylacrylate, 4-hydroxybutyl acrylate and diethyl maleate. The membrane had both fine permeation properties and perfect physical properties when three monomers were in the weight ratio of 4:4:2; this type of membrane was chosen as an optimized membrane. It was found that the membrane controlled clonidine zero-order release, the permeation rates decreased with the thicknesses of membranes increasing, and the permeation rates were linearly dependent on the square root of the concentration of clonidine. Furthermore, the optimized membranes were characterized by FTIR, DSC and SEM.     

The thermal reaction of HNCO at moderate temperatures

The thermal reaction of HNCO has been studied in a static cell at temperatures between 873 and 1220 K and a constant pressure of 800 torr under highly diluted conditions. The reaction was measurable above 1000 K by FTIR spectrometry. The products detected include CO, CO₂, HCN, NH₃, and the unreacted HNCO. In this moderate temperature regime, the rates of product formation and HNCO decay cannot be accounted for by a previously established high-temperature mechanism, assuming HNCO → NH + CO (1) as the initiation process. Instead, a new bimolecular reaction, 2HNCO → CO₂ + HNCNH (2), has been invoked to interpret the disappearance of HNCO as well as the formation of various products, most importantly CO₂. The concentration profiles of all measured species can be quantitatively modeled, throughout the temperature range analyzed, by varying k₂ using a modified mechanism. The kinetically modeled values of k₂ can be effectively represented by This result agrees closely with that computed with the conventional transition-state theory using the TST parameters predicted by the BAC-MP4 method: The bimolecular reaction takes place via a stable 4-membered ring intermediate which is isoelectronic with diketene; viz.      

线性变位极谱法研究 ⅩⅥ.铀(Ⅵ)-5-Br-PADAP-磺基水杨酸的配位吸附波

本文提出了铀(Ⅵ)-5-Br-PADAP-磺基水杨酸三元配合物的极谱配位吸附波。在pH为7.5-8.2的醋酸、三乙醇胺、乙醇底液中,该波的峰电位在-0.6855V(vs.SCE)。在1.00×10^-7-1.00×10^-5mol·dm^-3范围内,铀(Ⅵ)浓度与峰电流呈线性关系。对极谱波的电流、电位性质进行了研究,测定了配合物的组成、表观稳定常数和离解及生成速率常数。     

锗的市场结构变化与光纤通信

介绍了锗在光纤通信中的作用，分析了世界光纤市场的变化及其对锗的市场结构的影响，预测近期国内锗的市场结构不会有大的变化。     

Chiral organometallic triangles with Rh-Rh bonds. 2. Compounds prepared from enantiopure cis-Rh2(C6H4PPh2)2(OAc)2(HOAc)2 and their catalytic potentials

Enantiomers of the orthometalated dirhodium compound cis-Rh2(C6H4PPh2)2(OAc)2(HOAc)2 (R-1 and S-1) were prepared from carboxylate exchange reactions of the resolved diasteroisomers of cis-Rh2(C6H4PPh2)2(protos)2(H2O)2 (protos = N-4-methylphenylsulfonyl-l-proline anion) and acetic acid. These compounds react with excess Me3OBF4 in CH3CN, producing the enantiomers of [cis-Rh2(C6H4PPh2)2(CH3CN)6](BF4)2 (R-2 and S-2) which have six labile and replaceable CH3CN ligands in equatorial and axial positions. Reactions of R-2 and S-2 with tetraethylammonium salts of the linear dicarboxylic acids, terephthalic acid (HO2CC6H4CO2H), oxalic acid (HO2CCO2H), and 4,4'-diphenyl-dicarboxylic acid (HO2CC6H4C6H4CO2H) afford the enantiopure triangular supramolecules [cis-Rh2(C6H4PPh2)2(O2CC6H4CO2)(py)2]3, RRR-3 and SSS-3, Rh6(cis-C6H4PPh2)6(O2CCO2)3(py)5(CH2Cl2), RRR-4 and SSS-4, and Rh6(cis-C6H4PPh2)6(O2CC6H4C6H4CO2)3(py)4(CH2Cl2)2, RRR-5 and SSS-5, respectively. The absolute structures of each of the enantiomers of 1, 3, 4, and 5 were determined by X-ray diffraction analyses. The enantiomers of 3, 4, and 5 were found to be enantiomorphically isostructural, whereas R-1 and S-1 crystallized in different space groups. In 4 and 5, CH2Cl2 molecules coordinate to rhodium atoms in the axial positions. The 1H and 31P[1H] NMR spectra of all compounds are reported. The triangular compounds are redox-active, and their electrochemistry is also discussed. An assay of the catalytic activity/selectivity performance of the triangles for typical metal carbene transformation, using the model intermolecular cyclopropanation of styrene with ethyl diazoacetate in both homogeneous and heterogeneous phases, show that these chiral triangles are very active and have remarkable selectivity when compared with simple Rh2 paddle-wheel catalysts with chiral amidate ligands.     

Synthesis and near infrared luminescence of a tetrametallic Zn2Yb2 architecture from a trinuclear Zn3L2 Schiff base complex

Near infrared luminescence is observed in tetrametallic [Zn2Yb2L2(mu-OH)2Cl4].2MeCN which is obtained from the Zn3 Schiff-base complex [Zn3L2(NO3)2].MeOH, (H2L =N,N'-bis(5-bromo-3-methoxysalicylidene)propylene-1,3-diamine).     

Novel method for bulk resistance evaluation in conductivity measurement for high-purity water

A major issue with the electrolytic conductivity measurement for pure water is the lack of standard or reference methods. A primary method traceable to SI and suitable for pure-water conductivity measurement was developed at the Physikalisch-Technische Bundesanstalt (PTB), Germany, as the base for the calibration method for the conductivity measuring devices at the low conductivity level. This paper provides a novel method to calculate the bulk resistance of pure water using impedance measured at a single frequency, which is one of the key procedures for the primary methods.