REDUCTION OF C=C DOUBLE BOND WITH BOROHYDRIDE EXCHANGE RESIN-TRANSITION METAL COMPOUND SYSTEMS

Borohydride exchange resin-transition metal(Co,Ni,Cu,)compoundsystems reduced C=C double to C-C single bond in ethanol.     

室温下非极性溶剂中氧鎓盐的定域激发

氧鎓盐类化合物因具有较强的亲电性，在有机合成[1]及电照相体系[2]中存在着广泛的应用前景．由于它们还表现出较强的荧光发射能力［3］，因而在作为激光工作材料［4，5］方面也受到重视．正因如此，这类化合物的光物理和光谱特性引起了许多化学家的兴趣．氧钠盐化合物溶液的荧     

流通池介质交换差示脉冲阳极溶出伏安法用于多元素重叠峰的分离及其同时测定

本文用流通池介质交换差示脉冲阳极溶出伏安法在盐酸介质中富集,而以碳酸钠-碳酸氢钠缓冲溶液为溶出介质,有效地分离了酸性介质中Cu(Ⅱ)、Sb(Ⅲ)、Pb(Ⅱ)、Tl(Ⅰ)、Cd(Ⅱ)、In(Ⅲ)的重叠溶出峰,实现了多离子的同时测定。     

毛细管离子交换电色谱的分离行为

在离子交换毛细管色谱柱上实施电色谱，并对其分离行为进行了研究，采用７５μｍ（ｉ．ｄ．）２０ｃｍ的毛细管强阳离子交换柱（３μｍ）以ＮａＨ２ＰＯ４－Ｈ３ＰＯ４缓冲液为淋洗剂，紫外柱上检测（２１４ｎｍ）考察了流动相的ｐＨ值，有机改性剂及分离电压等因素对分离的影响，研究表明，不同的ｐＨ溶质的流出次序发生改变，随着有机改性剂含量增加，溶质的保留时间减小，而电渗流却增大，同时，对分离的柱效和方法的重现性进行了     

Synthesis of monodisperse poly(chloromethylstyrene-co-divinylbenzene) beads and their application in separation of biopolymers

The monodisperse, porous poly(chloromethylstyrene-co-divinylbenzene) beads of 7.9 microm were prepared by a single-step swelling and polymerization method. The seed particles prepared by dispersion polymerization exhibited good absorption of the monomer phase. Based on this media, a weak cation-exchange (WCX) stationary phase for HPLC was synthesized by a new chemically modified method. The prepared resin has advantages of biopolymer separation, high column efficiency, low column backpressure, high protein mass recovery, and good resolution for proteins. The dynamic protein-loading capacity of the synthesized WCX packings was 18.2 mg/g. Five proteins were separated in 3.0 min using the synthesized WCX stationary phase. The experimental results show that the obtained WCX resin has very weak hydrophobicity. The WCX resin was also used for the rapid separation and purification of lysozyme from egg white in 5.0 min with only one step. The purity and specific bioactivity of the purified lysozyme were found to be more than 93% and 70 245 U/mg, respectively.     

Spectral studies of bridged bisindenylmetallocenes and products of their reactions with polymethylalumoxane in toluene and dichloromethane in the visible region

Quantitative characteristics of changes in the energy of charge transfer from -bonded ligands to metal are presented for the series of structurally similar ansa-metallocene complexes of IVB Group elements. The changes are caused by the solvation effect, replacement of -bonded chlorine ligands by methyl groups and of bridging ethylene groups by dimethylsilylene moieties, introduction of the methyl substituent into position 2 and phenyl substituent into position 4 of the indenyl system, variation of the transition metal in metallocene, and formation of complexes with polymethylalumoxane (MAO) at different Al_MAO/Zr ratios. These effects are found to be additive.     

Case for projectile kinetic energy gain in stopping power studies

Under certain collision conditions, a swift ion projectile colliding with a target will gain rather than lose kinetic energy, contrary to the standard conception of stopping power. In this work, we consider the conditions for such a collision such that the energy loss is negative, that is, that there will be projectile kinetic energy gain. In particular, for a target initially in the ground state we find that the projectile gains kinetic energy only when charge exchange and de‐excitation processes are involved. This occurs when the electron affinity of the projectile is larger than the ionization potential of the target. Consequences of this effect are analyzed. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 94: 215–221, 2003     

甲烷部分氧化制合成气 Ⅰ．甲烷在过渡金属上的活化

文中用同位素交换（Ｄ_２─ＣＨ_４）反应来测量四种过渡金属负载型催化剂对甲烷的活化能力，并与Ｓｖｅｎｓｓｏｎ等从头算的计算结果作了比较，表明最有效活化甲烷分子的Ｃ─Ｈ键的金属是铑（Ｒｈ）．文中还测定了在甲烷部分氧化制合成气反应中，四个不同催化剂的催化活性与选择性，并与它们对甲烷的活化能力进行对比，可以看出甲烷部分氧化反应中，反应活性高的催化剂有效地活化甲烷，断裂Ｃ─Ｈ键，而且氘代甲烷产物分布以形成ＣＤ_４产物为主要成份．     

Mn位掺杂钙钛矿结构化合物LaSr2Mn2-xNixO7的磁性和电性的研究

The effect of Ni substitution for Mn on magnetic and transport properties has been investigated for layered manganese oxides LaSr₂Mn_2-xNi_xO₇. Nickel doping hampered the canted antiferromagnetic (AFM) exchange at low temperature and their Neel temperature (T_N) decreased from 138 K (x=0) to 102 K (x=0.3). Meanwhile, spin glass, charge ordering and metal-insulator transition are suppressed by Ni addition. The resistivity increases obviously with increasing x due to double exchange interaction channel broken by Ni²⁺ addition. The resistivity of all samples in low temperature range fits to the Mott′s variable rang hopping (VRH) model, while it fits to nearest neighbor hopping of small polarons model in high temperature range.     

The relative reactivities of various unsaturated compounds towards diisopropyloxy(η-cyclopentene)titanium

Competition experiments were performed by adding pre-formed solutions of diisopropyloxy(η²-cyclopentene)titanium in diethyl ether to various mixtures of unsaturated compounds at low temperature, establishing the following reactivity scale: aldehyde > nitrile > ketone > terminal alkyne > internal alkyne > terminal alkene > ester, carbonate.