直观教学法在化学理论课教学中的巧妙运用

针对理论性知识的特点,本文提出理科理论课教学中运用直观教学手段的基本指导思想,即宏观化、形象化、外显化；并举例阐释在这种理念的指导下,选择恰当时机运用最传统的直观手段,实现理论性知识教学价值的具体做法.     

同城高校联合模式资源共建共享的设想

同城高校联合模式是指分布在同一城市内的各大学之间建立的教学联合体,这种区域内校际间优势资源的共建与共享的实现,可以有效促进同城高校的共同发展和城市文化的进步,适应了提高城市建设现代化水平的需要.本文对同城高校联合模式资源共建共享的意义及实现途径进行了探讨.     

High-Current Multi-Finger Mesa InGaAs/InP DHBTs

Characteristics of single- and multi-finger mesa InGaAs/InP double heterojunction bipolar transistors （DHBTs） are compared. The current gain decreases with the increasing number nf of the emitter fingers due to the mutual thermal interaction between the fingers. The Kirk current can be as high as 150mA for four-finger DHBT. No degradation of the peak of the current gain cutoff frequency ft is found for multi-finger DHBTs. The peak of the maximum oscillation frequency fmax decreases with an increase of nf due to the increasing parasitic resistance of the base. The results are very helpful for applications of the common-base DHBTs in power amplifiers operating at very high frequencies.     

某轻钢厂房老基础再利用工程的设计与施工

文章介绍了某雪后重建钢结构厂房利用老基础进行设计、施工,对厂房老基础埋深、混凝土强度、配筋及基础截面尺寸进行检测,对原基础柱头水平、竖向承载力进行试验,对上部钢结构进行整体计算分析使其满足现行规范及利用原基础的要求,并对基础柱头与上部钢结构连接进行处理,给雪后及震后重建工程建设一定的启示.     

面向制造系统的多级物流配送模型及算法

针对制造系统供应链管理中多级配送运输存在的问题,采用仿真的方法进行模拟,设计一种合理算法,分析了供应链中物料沿着从最初的供应商流向其下游不同的生产商、装配商,完成整个制造形成产品的过程,揭示了生产商流向其下游批发商、零售商,最终到达用户手中实现其价值的规律.研究结果表明,这种多级配送模型和优化调度算法,对解决大规模配送决策问题具有可行性.     

小卫星星载计算机系统可靠性设计与分析

小卫星要求星载计算机系统可靠性高，重量轻，体积小，功耗低，针对“探索－1”立体测绘微小卫星（SMMS）的特殊性，设计了将集中控制与分布控制集于一身的星载计算机系统，并基于马尔可夫模型对其可靠性进行了分析。     

中外优秀男排选手扣球高度、速度的比较

针对排球扣球高度、速度是影响扣球效果的主要因素这一问题，利用三维摄像方法，对古巴、中国、波兰、加拿大四周男子排球队员的扣球高度、速度进行了研究。结果表明：古巴和中国等世界优秀男排选手扣球高度平均在3.00m以上，最高达3.31m；中国男排同古巴、波兰、加拿大男排相比，扣球高度偏低，特别是快球击球点低；古巴队选手挥臂速度快，击球力量大。     

一种交通需求级别预测法探讨

针对现行交通量预测方法存在的不足,提出了一种交通需求级别预测法,并认为在交通走廊拥堵区间可采用分级规划方式编制高速公路网长远规划.     

Determination of the Dominant Species and Reactions in Non-equilibrium CO<Subscript>2</Subscript> Thermal Plasmas with a Two-Temperature Chemical Kinetic Model

It has become increasingly clear that deviations from local thermodynamic equilibrium occur in thermal plasmas. This paper is devoted to investigating the non-equilibrium characteristics of CO₂ thermal plasmas, which have wide application in industry. A two-temperature chemical kinetic model with a comprehensive chemical system is developed to calculate the non-equilibrium characteristics of CO₂ thermal plasmas for a wide temperature range, from 12,000 to 500 K, at atmospheric pressure. The non-equilibrium results are compared to the equilibrium composition obtained by Gibbs free energy minimization, and significant deviations are found at lower temperatures. Based on the dependence of molar fractions on temperature, the dominant species are determined in three temperature ranges. The dominant reactions are then obtained by considering their contribution to the generation and loss of the dominant species. Using the dominant species and reactions, the full model is simplified into three simpler models and the accuracy of the simplified models is evaluated. It is shown that this approach greatly reduces the number of species and reactions considered, while showing good agreement with the full model, with a root-mean-square error of no more than 4 %. Thus, the complicated physicochemical processes in non-equilibrium CO₂ thermal plasmas can be characterized by relatively few species and reactions. It is suggested that the two-temperature chemical kinetic model developed in this paper can be applied to the full range of pressures that occur in arc welding, arc quenching and other industrial applications. In addition, the simplified methods can be applied in multi-dimensional models to reduce the chemical complexity and computing time while capturing the main physicochemical processes in non-equilibrium CO₂ thermal plasmas.