镧系金属一氢化物有效芯势研究

采用Cundari和Stevens等推导的有效芯势对镧系金属一氢化物进行了理论计算，以探讨镧系金属元素与氢的相互作用。结果表明所有镧系金属一氢化物基态时理论上是稳定的，最稳定的是SmH,最不稳定的是DyH;键长计算结果显示，基态时镧系金属一招兵买马花物有独立王国 收缩现象发生；红外振动频率理论计算值与实验结果一致；成键轨道中，金属原子轨道的贡献主要是s轨道和d轨道：从CeH至ErH(GdH)例外）随着外层电子的增加s轨道成分逐渐增大d轨道成分逐渐减小；从TmH和LuH（包括GdH)，成键轨道中金属原子轨道的贡献主要是d轨道，约为90％；约大多数镧系金属一氧化物的成键轨道中金属原子轨道f成分小于1％。     

微波消解-氢化物发生-原子荧光光谱法测定7种中草药中砷

利用原子荧光光谱法测定7种驱虫类中草药中的砷.实验采用微波消解样品,以盐酸为测定介质,硫脲-抗坏血酸为预还原剂,硼氢化钾为氢化剂,用氢化物发生-原子荧光光谱法测定砷含量.砷含量在10-100ng/mL浓度范围内线性关系好(r2=0.9924).回收率为93.83%-110.94%之间.方法简便、快速、灵敏、准确,可用于中草药中砷的测定.     

车前子中多糖含量的测定

采用蒽酮-硫酸法比色测定，用精制车前子多糖测得车前子多糖对葡萄糖的换算因子，对我国同属不同品种的车前子不同采集时间及炮制前后其多糖含量进行了比较研究。结果表明：此测定方法简便可行。供试液在8h内显色稳定，重现性较好，平均回收率为97．8％，RSD=1．41％(n=5)。江西吉安产大粒车前子生品多糖含量在9．15％～9．83％之间，炮制后其多糖含量在6．29％～6.81％之间；南昌新祺周车前GAP标准基地的大粒车前子生品多糖含量为7.85％～8．38％，炮制后其多糖含量为6．01％～6．64％；东北产的小粒车前子生品多糖含量为6．61％，炮制后其多糖含量为6．45％。     

基于MATLAB的异步电动机线性化控制系统的仿真

从异步电动机在同步旋转坐标系下的状态方程出发，在一定的条件下，对其系数矩阵简化．推出异步电动机的线性化控制模型．并基于该模型得出异步电动机的线性化控制系统．以给定电机为例，对该模型的有效性、响应用MATLAB进行仿真分析．验证的结果说明上述模型具有实用价值．     

二元液态金属Cu-Ni和Ag-Cu凝固过程的分子动力学模拟研究

用Quantum Sutton-Chen多体势对Ag6Cu4和CuNi液态金属凝固过程进行了分子动力学模拟研究.在冷却速率2×1012到2×1014K/s范围内,CuNi总是形成fcc晶体结构,而Ag6Cu4总是形成非晶态结构.考虑到CuNi及AgCu中原子半径之比分别为1.025和1.13,那么模拟结果证实了原子的尺寸差别是非晶态合金形成的一个主要影响因素.此外采用键对及原子多面体类型指数法对凝固过程中微观结构组态变化的分析,不但能说明二十面体结构在非晶态合金形成和稳定性中所起的关键作用,又有助于对液态金属的凝固过程、非晶态结构特征的深入理解.     

新型二硫纶·菲咯啉-5，6-二酮合铜(Ⅱ)配合物的磁性研究

报道了新合成的二氰基二硫纶·菲咯啉-5，6-二酮合铜(Ⅱ)配合物CuLL′(L=mnt^2-, 1,2-dicyano-1,2-ethylenedithiolate; L′=phen-5，6-dione, 1,10-phenanthroline-5,6-dione)的变温磁化率和电子顺磁共振波谱表征结果. 发现微晶粉体型的标题配合物CuLL′具有一定的顺磁性，形成四配位的近似于方形的结构. 探讨了这种配合物磁学特性与结构的关系.     

Synthesis and Photochemical Properties of a New Substituted Phenol Covalently Linked to Ruthenium （Ⅱ） Tris-bipyridine Containing Four Ester Groups as Sensitizer

As photosensitizer for solar cell, a new ruthenium (Ⅱ) complex with four ester groups had been synthesized, in which a phenol substituted by {[(2-hydroxy-5-tert-butylbenzyl)(pyridyl-2-methyl)amino]methyl} is covalently linked to ruthenium (Ⅱ) tris-bipyridine. The structures of the new compounds were confirmed by NMR and ESI-MS spectra. The electrochemical and photochemical properties were also studied.     

Studies on the Adsorption of Asymmetrical Triblock Copolymers by Scheutjens-Fleer Theory and Monte Carlo Simulation

The adsorption of asymmetrical triblock copolymers from a non-selective solvent on solid surface has been studied by using Scheutjens-Fleer mean-field theory and Monte Carlo simulation method on lattice model. The main aim of this paper is to provide detailed computer simulation data, taking A8-kB20Ak as a key example, to study the influence of the structure of copolymer on adsorption behavior and make a comparison between MC and SF results. The simulated results show that the size distribution of various configurations and density-profile are dependent on molecular structure and adsorption energy. The molecular structure will lead to diversity of adsorption behavior. This discrepancy between different structures would be enlarged for the surface coverage and adsorption amount with increasing of the adsorption energy. The surface coverage and the adsorption amount as well as the bound fraction will become larger as symmetry of the molecular structure becomes gradually worse. The adsorption layer becomes thicker with increasing of symmetry of the molecule when adsorption energy is smaller but it becomes thinner when adsorption energy is higher. It is shown that SF theory can reproduce the adsorption behavior of asymmetrical triblock copolymers. However, systematic discrepancy between the theory and simulation still exists.The approximations inherited in the mean-filed theory such as random mixing and the allowance of direct back folding may be responsible for those deviations.     

Production,Purification and Characterization of the Hen Egg-White Lysozyme Inhibitor from Enterobacter cloacae M-1002

Three hen egg-white lysozyme inhibitor producing strains, Enterobacter cloacae M-1002, E. sakazakii M-1204, and Erwinia rhapontici H-55, were isolated from the soils of Taiwan. E. cloacae M-1002 appeared to be a promising inhibitor producing strain. One inhibitor was isolated from the culture broth of this strain. Maximum lysozyme inhibitory activity was obtained when the bacterium was grown aerobically in a medium consisting of 0.75% glucose, 0.25% beef extract, 1.0% polypeptone, and 0.25% sodium L-glutamate (pH 70) at 37 °C after 36–48 hrs. A hen egg-white lysozyme inhibitor was isolated from the culture broth of this strain. The inhibitor was purified from the culture supernatant of E. cloacae M-1002 by ammonium sulfate fractionation, DEAE-Sepharose CL-6B column chromatography and Fractogel TSK HW-55 (S) gel chromatography. Molecular weight of the purified lysozyme inhibitor was estimated to be 18, 000–20, 000 by SDS-PAGE and HPLC, and was composed of 71% amino acid and 23% total sugar. Serine, glycine, and alanine in a 3:2:1 molar ratio were the major amino acids, calculated to be 32.8, 20.3, and 11.4% (mol%), respectively. Glucose and mannose were the major sugar components of the inhibitor. The inhibitor was stable at pH 5 to 8 and was stable under 50 °C. Only hen egg-white lysozyme was inhibited by the purified inhibitor but not the other tested enzymes such as lysozyme of celery, turnip; lytic enzyme of Pseudomonas aeruginosa M-1001; chitinase/lysozyme of P. aeruginosa K-187; or cellulase and xylanase of Streptomyces actuosus A-151 and Aspergillus sp. G-393. The inhibition of lysozyme to the bacterial cell lytic activity by the purified inhibitor was 100%.     

广义的一维Fibonacci结构

本文提出一维k组元的Fibonacci结构,它包含k个无公度的基本长度,是具有两个基本长度的标准Fibonacci结构的自然推广,投影理论被用来处理它的X射线衍射花样及其指标化问题,理论模拟被用于验证投影理论的结果,值得注意的是,对于有限的链长,当k足够大时,它的衍射谱将趋于混沌。 关键词：