用改进嵌入原子法计算Cu晶体的表面能

用改进嵌入原子法(MEAM)计算了Cu晶体12个晶面的表面能.结果表明，密排面(111)的表面能最小.其他晶面的表面能随其晶面与(111)晶面夹角的增加而增加，据此可以粗略地估计各晶面表面能的相对大小.给出的几何结构因子的确定方法及结果可以直接用于计算其他面心立方晶体的表面能及其他特性.在Cu,Ag等面心立方薄膜中出现(111)择优取向或织构的机理是表面能的最小化. 关键词： 改进嵌入原子法 铜 表面能 计算     

Study of the pulsed laser vapor doping of Si(1 0 0) with KrF excimer laser and BCl3 gas

The properties of pulsed laser vapor doping on p-Si(1 0 0) with a KrF (248 nm) excimer pulsed laser (248 nm) and BCl₃ gas are reported in this paper. The doped samples are characterized by the resistance measured using a four-probe method, since the sheet resistance changes with the carrier concentration of the sample. The doping effects with the variation of laser energy density, pulse number, and the pressure of BCl₃ were investigated in terms of the sheet resistance. In this way, the optimized parameters were obtained and used for the positive heavy doping on p-Si(1 0 0) and p-Si(1 1 1). Then, using a square mesh under the above conditions, an image doping was completed. Finally, the metal–semiconductor Ohmic contacts were realized by plating Ag and Cu films on the doped surface.     

Lower-dimensional linear complementarity problem approaches to the solution of a bi-obstacle problem

A globally convergent Broyden-like method for solving a bi-obstacle problem is proposed based on its equivalent lower-dimensional linear complementarity problem. A suitable line search technique is introduced here. The global and superlinear convergence of the method is verified under appropriate assumptions.     

High performance 1689-nm quantum well diode lasers

1689-nm diode lasers used in medical apparatus have been fabricated and characterized. The lasers had pnpn InP current confinement structure, and the active region consisted of 5 pairs of InGaAs quantum wells and InGaAsP barriers.     

CAS based approach for discussing subset construction

This paper continues the discussion of teaching nondeterminism (see [6]) where we presented a didactic approach introducing the notion of nondeterministic automata. Although in this paper we use the same methodology we have to face up to new didactic challenges. Namely, teaching the subset construction requires answers to the question how can CAS be used in teaching the different phases of mathematical problem solving so that we can reach higher cognitive efficiency.     

A multifractal decomposition according to rate of returns

For one‐dimensional simple symmetric random walk, the Hausdorff and packing dimensions of sets of sample paths with prescribed rate of returns to the origin are determined. This gives a multifractal decomposition of the underlying sample space. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

析氢反应动力学的交流阻抗法研究

利用交流阻抗法测定析氢电化学动力学参数，得到与极化曲线法一致的结果，为确定复杂析氢过程速率的决定步骤提供了判据。     

五羟色胺分子选择性电极研究

本应用自己合成的联萘２０－冠－６作为活性载体，进行了五羟色胺分子选择性电极研究。电极在１０＾－＾５－１０＾－＾２ｍｏｌ／Ｌ浓度范围内对五羟色胺具有稳定的线性响应，平均斜率为６３ｍＶ／ＰＣ，检测下限为２．７×１０＾－＾６ｍｏｌ／Ｌ。