含硫原子簇化合物的三阶非线性光学性质

总结近年来Mo(W，V)／S／Cu(Ag，Au)含硫原子簇化合物的三阶非线性吸收与非线性折射等光学性质的研究状况，Mo(W，V)／S／Cu(Ag，Au)含硫原子簇化合物的结构与光学性质之间的关系。     

Cu-Sn-P-LiMn2O4纳米复合材料镀层的XPS和AES研究

采用化学复合镀技术，在Q₂₃₅碳钢片表面制备了Cu-Sn-P-LiMn₂O₄纳米复合材料镀层。用扫描电子显微镜(SEM)观察外貌；称重法测定厚度；通过5% NaCl溶液、1% H₂S气体加速腐蚀试验、抗粘性试验及室温氧化试验等多种手段测定其性能。用X-射线光电子能谱(XPS)及俄歇电子能谱(AES)测定其价态及组成。结果表明:Cu-Sn-P-LiMn₂O₄纳米复合材料镀层的性     

纳米尺寸材料的结构和性质III：铁纳米粒子的结构和性质

Molecular dynamics computer simulation has been carded out to study the structure and physical properties of iron nanoparticles with 331 to 2133 Fe atoms or with diameter from 2.3 to 4.3 nm. The core of liquid nanodroplets has the similar structure of the bulk molten iron liquid that has an average coordination number around 10.5 and the packing density around 0.45, although the closest Fe-Fe distance is slightly longer in the bulk liquid. Most of the iron nanoparticles formed from the cooling of molten nanodroplets have the same body center cubic crystal structure as it was observed in the bulk under the normal temperature and pressure. Lattice contraction was observed for iron nanoparticles. An amorphous solid and an HCP like solid were obtained accidentally during the quenching runs on Fe331 nanoparticles. The physical properties of iron nanoparticles such as molar volume, density, thermal expansion coefficient, melting point, heat of fusion, heat capacity and diffusion coefficient were estimated based on the results obtained from this simulation. The dependence of physical properties on the nanoparticle sizes was addressed.     

普利沙星与Co(phen)_3~(2+)及DNA间结合作用的电化学和光谱

利用电化学和紫外光谱法研究了邻菲咯啉合钴(Co(phen)32+)与普利沙星(PLFX)及DNA间在pH=7.4的三羟甲基氨基甲烷-盐酸缓冲溶液中的结合作用。紫外光谱测量结果表明,普利沙星与Co(phen)32+发生了结合作用形成二元络合物,结合常数为2.0×104L/mol。电化学测量表明,在Co(phen)32+-普利沙星络合物中加入DNA后,Co(phen)32+-普利沙星络合物的峰电流下降,峰电位差增大了17 mV,式电位负移了3.5 mV,推断络合物与DNA作用方式主要为静电作用。     

电位溶出法同时测定粮食中镉铅铜

应用正交试验设计,通过实验综合考察了各种影响因素,选出了最佳分析条件,用于粮食中镉、铜、铅的测定。试剂与仪器见文献[1]。一、实验方法取Cd~(2+)、Pb~(2+)、Cu~(2+)标准各0.5μg置于10mL刻度管中,加入2.50mL 4.0mol/LKCl溶液和一定量的Hg(Ⅱ),用0.1mol/L HCl调至pH为2,用水稀至10.00mL,转入电解池中,插入预处理过的电极(三电极体系),搅拌,通氮5min,在-0,9V富集一定时间,在氮气氛下记录电位对时间的曲线,用标准加入法计算Cd、Pb、Cu的含量。     

Molecular Dynamics Studies of the Kinetics of Phase Changes in Clusters IV： Crystal Nucleation from Molten （NaCl）256 and （NaCl）500 Clusters

Molecular dynamics computer simulation based on the Born-Mayer-Huggins potential function has been carried out to study the effects of duster size and temperature on the nucleation rate of sodium chloride dusters in the temperature range of 580 K to 630 K. Clusters with 256 and 500 NaCl molecules have been studied and the results have been compared with those obtained from 108 molecule dusters. The melting point (MP) of the clusters were observed to increase with the size of the clusters and can be well described by a linear equation MP =1107(37)-1229(23)N^-1/3(N is the number of molecules in the duster).The nucleation rate was found to decrease with increasing the duster size or temperature. Various nucleation theories have been used to interpret the nucleation rates obtained from this molecular dynamics simulation. It is possible to use a constant diffuse interface thickness to interpret the nucleation rate from the diffuse interface theory in the temperature range of this study. However, the interfacinl free energy estimated from classical nucleation theory and diffuse interface theory increases too fast with increasing the temperature while that from Gran-Gunton theory does not change with changing temperatures.The sizes of critical nuclei estimated from all the theories are smaller than those estimated from our simulations.     

J/ψ→γγ测量的蒙特卡罗研究

J/ψ→γγ是朗道-杨定理禁戒的过程，对该过程的研究能够为寻找新物理提供重要的信息。精确测量该过程的分支比，进而限制理论预期值的范围，能够用于检验C宇称守恒及寻找新物理。本研究将利用106Mψ（3686）单举蒙特卡罗样本研究在北京谱仪-Ⅲ上测量该过程能够达到的精度。本研究在90％置设定了该过程观测事例数的上限，并计算得到其分支比的上限为5．6×10^-7，此研究结果为在BESIII上进行相关实验提供了依据。     

N—苯磺酰基甲基苯胺与芳醛的缩合反应

由Ｎ－苯磺酰基甲基苯胺与芳醛反应得到了７种缩合产物，其结构经元素分析，ＨＮＭＲ，ＭＳ和ＩＲ所确证。     

基于折叠势的两势方法系统研究质子放射性(英文)

基于两势方法系统地研究了质子数51 ≤ Z ≤ 83质子放射性核素的衰变半衰期。总的质子-子核相互作用势包括:通过单折叠子核密度和DDM3Y有效相互作用得到的微观核势,通过单折叠子核电荷密度和质子-质子库仑相互作用得到的真实库仑势以及离心势。同时,预测了同一区域16个核的质子放射性半衰期,并且预测的质子放射性半衰期在4.11倍的范围内。此外,还研究了质子放射性的Geiger-Nuttall定律。结果表明,Geiger-Nuttall定律可以用来描述角动量相同的同位素的质子放射性。In the present work, we systematically study the half-lives of proton radioactivity for 51 ≤ Z ≤ 83 nuclei within the two-potential approach. The total emitted proton-daughter nucleus interaction potential is composed of the microscopic nuclear potential obtained by single folding the density of the daughter nucleus with the DDM3Y effective interaction, the realistic Coulomb potential obtained by single folding the charge density of the daughter nucleus with the proton-proton Coulomb interaction and the centrifugal potential. We extend our study to predict proton radioactivity half-lives of 16 nuclei in the same region within a factor of 4.11. In addition, the Geiger-Nuttall law for proton radioactivity is researched. The results indicate that the Geiger-Nuttall law can be used to describe the proton radioactivity isotopes with same angular momentum.