L－B膜修饰电极循环伏安行为模拟──（Ⅰ）电荷转移速度常数对循环伏安性能的影响

本文用计算机数字模拟方法研究了电活性分子多层Ｚ型Ｌ－Ｂ膜修饰电极的循环伏安行为。计算了电极与修饰Ｌ－Ｂ膜分子第一层之间的电荷转移速度常数Ｋ_ｏ，Ｌ－Ｂ膜分子层间的电荷转移速度常数ｋ_ｉ；对峰电位差△Ｅ_ｐ及阳极峰面积Ｑ的影响，以及在不同条件下各层分子的氧化态分数随扫描时间的变化。为研究和设计电活性分子修饰电极的实际体系提供了大量数据和信息。     

Electrode Evaporation Effects on Air Arc Behavior

A numerical study of the effects of copper and silver vapours on the air arc behavior is performed. The commercial software FLUENT is adapted and modified to develop a twodimensional magneto-hydrodynamic （MHD） models of arc with the thermodynamic properties and transport coefficients, net emission coefficient for the radiation model of 99% ai-1% Cu, 99% air-1% Ag, and pure air, respectively. The simulation result demonstrates that vaporization of the electrode material may cool the arc center region and reduce the arc velocity. The effects of Ag vapour are stronger compared to those of Cu vapour.     

Numerical investigation of fracture behavior of tunnel by excavation loading

A rock failure process analysis model, RFPA2D code, a two-dimensional numerical code, were proposed. The code not only satisfied the global equilibrium, strain consistent and nonlinear constitutive relationship of rock and soil materials but also took into account the heterogeneous characteristics of rock materials at macroscopic and microscopically level. The failure behavior of tunnel could be simulated by this numerical model. The model could realistically simulate the fracture behavior of tunnel by excavation loading, strength limits, and post peak response for both tension and compression. As the proposed method was used to conduct the stability analysis of tunnel, the safety factor of tunnel was defined as the ratio of actual shear strength parameter to critical failure shear strength parameter. Not only the safety factor of tunnel with specific physics meaning can be obtained, but also the overall failure process and the location of failure surface may also be determined at the same time.     

烟火剂的激光二极管点火第一部分：数字模拟

创立了一个在激光光束作用下,反应国体的变热和点火过程的数字模型。采用一种显示模式（explicit scheme),对瞬态的、二维热方程进行了数字式求解。一个非线性的源项（source term,指Arrhenius方程）使得对这类问题的分析求解变得复杂化。激光束的吸收深度被认为只有几个微米深。研究了吸收深度系数的作用。用这种模型测定了激光能量密度、激光照射时间和热扩散率对点火的效应。这种数字模型已经被用到了对炸药类的激光点火系统的设计当中。证明了用纤维光导输出为0．6W的激光二极管进行点火是最合适不过的。     

欧胜推出音效数字模拟转换器产品

欧胜微电子有限公司日前宣布：公司推出针对高端音频应用的新型超高性能立体声数字模拟转换器（DAC）WM8741。这款独具创新的WM8741不仅巩固了欧胜在高性能音频方面的领导地位，而且为欧胜AudioPlus增长策略进一步奠定了基础。该战略集成了新增的混合信号技术和音频信号链所包含的关键部分，为最终用户提供全新的升级体验。     

欧胜推出WM9081

欧胜微电子宣布推出一款产品编号为WM9081的新型单芯片单声道数字模拟转换器（DAC）和扬声器放大器,它是让低成本扬声器提供最佳声压级（SPL）和最大解析度的理想之选,这类扬声器通常用在各种便携导航设备、移动电话、数字收音机和会议电话等设备中。     

竖向切缝在高大冷却塔拆除爆破中的作用

介绍了广东省茂名市某热电厂1座123.2m高冷却塔的爆破拆除。通过竖向切缝,用以减弱塔身的整体刚性,加大其失稳条件,促使塔体倾倒和加强解体破碎效果。对冷却塔爆破切口和竖向切缝进行了爆破设计,对冷却塔的倒塌过程进行了数值模拟与结果分析。工程实践表明,切口上部的竖向切缝对冷却塔的加速倒塌、减小振动和控制爆堆范围等方面都有一定的作用。本工程提供的经验可供类似工程参考。