压制球形药包解决退模问题的技术措施

文中简要阐述了在制备球形药包过程中,为解决压装药件的退模问题所采取的技术措施,并提出了较佳的成型底座的设计方案。     

The determinants of heat-shock element-directed lacZ expression in Saccharomyces cerevisiae.

Heat-shock induction of heat-shock protein genes is due to a specific promoter element (the heat-shock element, HSE). This study used lacZ under HSE control (HSE-lacZ) to characterize HSE activity in Saccharomyces cerevisiae cells of different physiological states and differing genetic backgrounds. In batch fermentations HSE-lacZ induction by heat shock was maximal in exponential growth, and showed marked decline with the approach to stationary phase. Expression in the absence of heat shock was unaffected by growth phase, indicating that the growth-dependent expression of many yeast heat-shock genes uses promoter elements in addition to the HSE. Heat-induced expression was strongly influenced by the temperature at which cultures were grown. While basal, uninduced expression was constant during growth at different temperatures to 30 degrees C, induction by transfer to 39 degrees C was reduced by increases in growth temperature as low as 18-24 degrees C. Maximal HSE-lacZ induction (30- to 50-fold) was in cultures grown at low temperatures (18-24 degrees C), then heat shocked at 39 degrees C. Ethanol was a poor inducer. Mutations having little effect on HSE-lacZ expression included a respiratory petite; ubi4 (which inactivates the poly-ubiquitin gene); also ubc4 and ubc5 (which each inactivate one of the ubiquitin ligases involved in degradation of aberrant protein). pep4-3 increased both basal and induced beta-galactosidase about two-fold, probably because of slower turnover of this enzyme in pep4-3 strains.     

高梯度加速管的束流传输

对不同能量、不同质量数、不同初始条件的入射束和有无空间电荷效应的离子束流在高梯度加速管中的传输进行了计算，并讨论了一些影响加速管聚焦作用的主要因素，计算结果与实际情况相符。     

HIN2xxE系列RS-232收发器的原理及应用

HIN2xxE系列是由＋5V单电源供电的高速RS-232收发电路，符合EIARS-232C和V．28规范，以电源功耗低为显著特点，广泛应用于ISDN和高速调制解调器，尤其是电池供电系统中。文中主要介绍HIN2xxE系列电路的原理、特性和典型应用。     

微波感应式电力线防盗在线监测系统

研制了一种微波感应式配电线路防盗在线监测系统，简述了其系统构成、技术特点和应用效果。整个系统由监测分机、监控中心、巡检人员组成，借助该系统进行了一系列实验。结果表明，当有大型移动物体靠近或攀登杆塔时，安装在杆塔上10 m左右的微波感应监测分机感应到移动物体信号，一方面进行语音警示，另一方面通过短信服务及时向监控中心发送短信，监控中心及时通知巡检人员，赶到事故现场，以最大限度地保证输电线路的安全。     

a—Si：H TFT电流—电压特性研究

本文发展了一种研究ａ－Ｓｉ：Ｈ ＴＦＴ电流－电压特性的新方法。基于局域态电荷密度解析统一模型，提出并深入分析了沟道区有效温度参数的概念，并由此推导出了ａ－Ｓｉ：Ｈ ＴＦＴ电流－电压特性的解析表达式。其理论值与实验值符合很好。该模型可用于ａ－Ｓｉ：Ｈ ＴＦＴ静态特性分析及其电路优化。     

条形药包爆炸应力场试验研究

应用动态光弹性模型试验方法研究了条形药包的爆炸应力场分布特性。研究结果表明：起爆方式和位置影响着条形药包爆炸应力场的分布形态，并首次成功地记录了条形药包瞬间爆炸应力场的动光弹条纹，得到了理想成力场的分布形式。     

Modelling of induced aeration in turbine aerators by use of radial basis function neural networks

Gas induction in agitated vessels with turbine impellers can be modelled accurately by means of radial basis function neural nets. The results obtained with the radial basis neural net were significantly better than those obtained by multivariate regression models or standard back propagation neural nets. Moreover, by using the radial basis function neural net model, it was possible to conduct a sensitivity analysis of the variables affecting aeration. Increased medium density showed a strong adverse effect, while variation of the viscosity can cause an increase or a decrease in the rate of aeration, depending on the prevailing process conditions.     

A New Approach to Abstract Syntax with Variable Binding

The permutation model of set theory with atoms (FM-sets), devised by Fraenkel and Mostowski in the 1930s, supports notions of ‘name-abstraction’ and ‘fresh name’ that provide a new way to represent, compute with, and reason about the syntax of formal systems involving variable-binding operations. Inductively defined FM-sets involving the name-abstraction set former (together with Cartesian product and disjoint union) can correctly encode syntax modulo renaming of bound variables. In this way, the standard theory of algebraic data types can be extended to encompass signatures involving binding operators. In particular, there is an associated notion of structural recursion for defining syntax-manipulating functions (such as capture avoiding substitution, set of free variables, etc.) and a notion of proof by structural induction, both of which remain pleasingly close to informal practice in computer science. Received October 2000 / Accepted in revised form April 2001     

Simulating the Child's Acquisition of the Lexicon and Syntax—Experiences With Babel

This paper describes the theory and implementation ofBabel, a system which explores the hypothesis that much of the differences in the world's languages may be characterized by the inventory and properties of the lexical items and functional categories of those languages. The structure ofBabel assumes that functional categories are originally lacking in a child's syntax, and are acquired through a statistical induction process of lexical acquisition.Babel then uses information induced from the structure of the lexicon to create a model of syntax via a deductive, rule-based process. This model makes a number of predictions about the time course of language acquisition. These predictions are tested by runningBabel as a simulation of child language acquisition, using large samples of adult speech to children as input. The simulation results are shown to highly correlate to longitudinal studies of child language acquisition in English and Polish. Finally, the approach to handling noisy data withBabel is detailed.