Singlet-Triplet Transition in Quantum Dots Confined by Triangular and Bowl-Like Potentials： the Effect of Electric Fields

We theoretically investigate the energy spectra of two-electron two-dimensional （2e 2D） quantum dots （QDs） confined by triangular potentials and bowl-like potentials in a magnetic field by exact diagonalization in the framework of effective mass theory. An in-plane electric field is found to contribute to the singlet-triplet transition of the ground state of the 2e 2D QDs confined by triangular or bowl-like potentials in a perpendicular magnetic field. The stronger the in-plane electric field, the smaller the magnetic field for the total spin of the ground states in the dot systems to change from S = 0 to S = 1. However, the influence of an in-plane electric field on the singlettriplet transition of the ground state of two electrons in a triangular QD modulated by a perpendicular magnetic field is quite small because the triangular potential just deviates from the harmonic potential well slightly. We find that the strength of the perpendicular magnetic field needed for the spin singlet-triplet transition of the ground state of the QD confined by a bowl-like potential is reduced drastically by applying an in-plane electric field.     

一维粗糙表面散射特征的数值分析

使用Monte Carlo模拟的方法得出了随机粗糙表面，在Kirchhoff近似的基础上，利用数值分析的方法分析了一维随机粗糙表面的散射特征，得出了一维随机粗糙表面散射分布曲线，我们还考虑了遮蔽效应的影响，并且讨论了Kirchhoff近似的有效性。     

Dissociative Chemisorption of an H2（v,j） Molecule on Rigid Ni （100） Surface： Dependence on Surface Topologies and Initial Rovibrational States of the Molecules

The H2(v,j) Ni(100) collision system has been studied to understand the effects of the surface sites and initial rovibrational states of the molecule on molecule-surface interactions, by a quasiclassical molecular dynamic simulation method. Dissociative adsorption of an H2 molecule on the rigid Ni(100) surface is investigated at topologically different three sites of the surface. Interaction between the molecule and Ni surface was described by a London-Eyring-Polani-Sato (LEPS) potential. Dissociative chemisorption probabilities of the H2(v, j) molecule on various sites of the surface are presented as a function of the translation energies between 0.001-1.0eV. The probabilities obtained at each collision site have unique behaviour. At lower collision energies, indirect processes enhance the reactivity, effects of the rotational excitations and impact sites on the reactivity are more pronounced. The results are compared with the available studies. The physical mechanisms underlying the results and quantum effects are discussed.     

Effects of External Electric Field on Ferroelectric Superlattice with Two Alternating Layers

The effects of the external electric field on the ferroelectric superlattice with two alternating layers have been studied using the transverse Ising model based on the effective-field theory with the differential technique. The hysteresis loops and susceptibility of the system have been given. The stronger the external electric field, the smaller the susceptibility, reflecting that the polarization is weaker.     

电场对水结构的影响—电场处理水的应用机理研究

水经电场作用后，能使其内部结构发生变化，造成它的理化特性出现一系列改变，根据所提供的实验数据，提出电场可引起部分水分子的氢氧键断裂，使水中出现过量的超氧阴离子自由基，过氧化氢及自由质子，这一结论可满意地解释如下现象：用电处理水喂养纤毛虫，其分裂速度加快；受电场刺激的鱼胚胎，其孵化率，存活率明显提高，其后期生长速度加快等。     

冲击波对结晶MgO晶体结构,表面性质和催化剂性能的影响

用ＸＲＤ，ＥＳＲ和ＴＰＤ等技术研究冲击波处理的结晶ＭｇＯ后发现，ＭｇＯ的晶格发生畸变，微应力值ε１／２Ｄ显著增大，有大量缺陷产生并形成Ｆ心，晶体的平均晶粒减小，且表现出各向异性，从而引起了催化剂表面碱中心强度增大，数目变化，在对乙烷氧化脱氢反应中表现出较高的活性和对乙烯的选择性，初步讨论了可能的结构模型和催化机理。     

电场喷射活细胞

一般人使用喷墨打印机来打印文件和图片＋这种技术将细小的彩色墨滴从喷嘴中挤压出来．然而，在电子学和医学中正越来越多地用这种技术产生小体积的液滴．例如，使用压电晶体从一根针头中挤压出含有细胞的溶液，产生活细胞的二维和三维图像．但是细胞液滴的大小受到针头直径大小的限制＋因而这种方法不能产生小于100μm同左右的液滴．这意味着很难制成带有细微特征的小的生物组织．     

氧碘化学激光气固相化学反应体系热力学分析

氧碘化学激光器（COIL）的发展已经到了提高系统安全性和工作环境适应性、降低系统复杂性阶段，而改进O2（^1△g）的产生方式和方法正是这个阶段的重要工作内容之一。近期，美国空军研究实验室运用气-固相反应方式产生O2（^1△g）。采用碱金属过氧化物或碱土金属过氧化物与卤化氢反应，生成O2（^1△g）。通常气一固相反应有着反应速度慢，接触面积小，反应产物难以脱出固体表面的缺陷，使得产出率低，而不被广泛采用。但随着表面化学研究的突飞猛进，借助表面活化分子，特殊性质的表面构造，大表面的构造，都为气一固相反应的进行提供了可行途径。如果此方法能用在氧碘激光器上，将克服传统方法的诸多不足。     

Deformation Morphology underneath the Vickers Indent in Bulk Metallic Glasses

Plastic deformation behaviour of Zr52.5Al10Ni10Cu15Be12.5 and Mg65Cu25Gd10 bulk metallic glasses (BMGs) is studied by using the depth-sensing nanoindentation and microindentation. The subsurface plastic deformation zone of the BMGs is investigated using the bonded interface technique. Both the BMGs exhibit the serrated flow depending on the loading rate in the loading process of indentation. Slow indentation rates promote more conspicuous serrations, and rapid indentations suppress the serrated flow. Mg-based BMG shows a much higher critical loading rate for the disappearance of the serration than that in Zr-based BMG. The significant difference in the shear band pattern in the subsurface plastic deformation zone is responsible for the different deformation behaviour between the two BMGs. Increase of the loading rate can lead to the increase of the density of shear bands. However, there is no distinct change in the character of shear bands at the loading rate of as high as1000 nm/s.