ZnO压敏陶瓷最佳掺杂含量的理论计算

从对电子薄膜材料研究中得到的最佳掺杂含量定量理论推广到ZnO陶瓷材料。该理论建立了电子薄膜材料的某一物理性能与晶体结构、制备方法和掺杂剂含量之间的联系，给出了一个能够拟合实验曲线的具有确定物理意义的抛物线方程。该方程的极值点确定了最佳掺杂含量与晶体结构和制备方法之间的定量关系，进而得到了一个掺杂最佳含量的表达式。系统地分析了ZnO压敏陶瓷的掺杂改性的实验结果，应用此表达式定量计算了ZnO压敏陶瓷的最佳掺杂含量，定量计算的结果与实验数据相符合。该理论也适用于其他薄膜材料最佳掺杂含量的理论计算。     

碘量法测铜中物质性质和分析操作

本文讨论了碘量法测定铜量中一些有关物质的特性,以及这些性质对分析条件和操作的要求。     

降低氧化铝生产中熟料折合比的探讨

在氧化铝生产过程中，熟料折合比是烧结法一项重要的综合性指标，本文通过对熟料折合比的定义、计算公式的剖析，分析了生产过程中影响熟料折合比的主要因素，对有效降低熟料折合比的措施进行了探讨。     

无差拍控制提高变速异步风力发电系统的故障承受能力

变速风力发电机对于电网扰动、故障以及电网电压跌落非常敏感，当上述情况发生时风力发电机将从电网切除，直到电网恢复正常才能重新投入运行。如何在电网发生扰动时保持风力发电机的正常运行是一个有挑战性的课题。未来的电网规范甚至要求在电网发生故障时风力机组仍能保持运行，这就要求必须安装保证风电机组低电压运行的控制装置。文中针对采用全载换流器与电网进行连接的异步风力发电机组提出了相应的风电机组低电压控制器及控制策略，无须进行硬件改造即可实现电网故障情况下风电机组不退出运行。其中，风电机组电气子系统控制器基于无差拍控制策略进行设计。算例给出了300 kW的风电机组在30%电压跌落情况下的暂态过程，没有加入控制器之前风电机组将停机，加入之后则可以保持运行，验证了所提方法的正确性。     

Necessary optimality conditions in a nonsmooth control problem with variable structure

An optimal control problem with nonsmooth performance criterion described by a system of ordinary differential equations is considered. Necessary first-order optimality conditions are obtained.     

Trypsin inhibitor activity of soybean as affected by genotype and fertilisation

The presence of protease inhibitors in soybean prohibits the utilisation of the raw beans for food and feed. However, little information is available about environmental influences and the effects of nitrogen and sulphur supply on the antinutritional constituents of soybean. As these factors may influence protease inhibitors, soybean genotypes segregated according to the presence or absence of the Kunitz trypsin inhibitor have been evaluated for trypsin inhibitor activity (TIA) in field trials. TIA was affected significantly by environment (geographical location), fertilisation treatment and genotype. Environmental means of TIA were between 69.5 and 104.8 mg g^?1. Nitrogen application, which caused an increase in seed protein content, resulted in a reduction in TIA by about 15% as compared with the control. Remarkably, simultaneous application of nitrogen and sulphur in the form of ammonium sulphate had a similar reductive effect on TIA to that of nitrogen application alone, although soybean protease inhibitors are rich in sulphur amino acids. Significant genetic variation in TIA was found both within the genotype class with the Kunitz inhibitor present as well as within the class lacking this inhibitor. The results suggest that TIA of soybean may be modified considerably by genetic improvement and appropriate agronomic management. Copyright © 2003 Society of Chemical Industry     

Empirical Evaluations of Usage-Based Reading and Fault Content Estimation for Software Inspections

This thesis describes six empirical investigations of two techniques applied to software inspections, namely reading techniques and fault content estimation techniques. The first part of the thesis presents a series of experiments of a novel reading technique called usage-based reading. The second part investigates fault content estimation applied to the software inspection process. The estimation methods used are capture-recapture and curve fitting.     

谈电视教材节奏的处理

电视教材的节奏包含两个方面的内容:其一是内容情节节奏,其类型选择要根据教学内容、教学目标、教学对象、教学组织形式、电视教材类型而定;其二是表现形式节奏,主要包括画面的视觉节奏、摄像机镜头的运动节奏、景别变化节奏、镜头长度节奏、镜头组接节奏、应用电子特技产生的节奏、声音节奏等。     

ICP-AES法测定硅铝钡合金中的钡

介绍ICP—AES法测定硅铝钡中的钡的分析方法，用氢氟酸一硝酸一高氯酸混合酸溶解试样，用钡的233．527nm谱线测定钡．该方法简便快速，精密度好，准确度高，加标试验回收率为99％～100％，相对标准偏差为0．25％～0．56％．     

集团变分法(CVM)及其在合金相图计算中的应用

介绍了集团变分法的集团概率变量、配置熵等统计分析的理论基础及Helmholtz自由能的描述模型.提出了巨势及相对化学势的几何分析理论.讨论了应用集团变分法和巨势分析理论进行相平衡计算的过程,并分析了同结构平衡相图计算的若干实例.