洁净系统中激光诱导颗粒污染物的分析与评估

高功率激光系统要求在洁净环境中运行,若光学元件表面在工作过程中附着污染物,将导致光学元件的损伤及整个系统负载能力的下降。针对洁净系统中激光与材料作用而产生的颗粒物,分析其作用机制,探讨用于评估的理论依据,讨论测量的需求和方法,并对系统表面存在的颗粒污染物进行了实际测量分析,提出了深入开展高功率激光系统中颗粒污染物测量与评估的技术途径。     

DEVELOPMENT OF SURROGATE LUNG SYSTEMS WITH CONTROLLED THERMODYNAMIC ENVIRONMENTS TO STUDY HYGROSCOPIC PARTICLES: AIR POLLUTANTS AND PHARMACOLOGIC DRUGS

An objective of this text is to demonstrate advantages of interdisciplinary efforts, specifically, applications of engineering technology to health effects issues. The work describes the development of surrogate systems of the human lung for use in studies of hygroscopic growth kinetics and related deposition of inhaled particles. The models have become increasingly more physiologically realistic. Notable accomplishments are the successful simulations of in vivo environmental conditions, namely: (1)temperature and relative humidity atmospheres;(2)airstream profiles and thermodynamic processes; and,(3)lung morphology. Measurements of hygroscopic characteristics of a laboratory aerosol (NaCl) and bronchodilator drugs used in aerosol therapy were made using one of the models and are reported herein. The data clearly demonstrate the respective effects of respiratory tract geometry and particle chemical composition upon the behavior of inhaled substances. The surrogate lungs, offering unique research opportunities detailed within, are intended for experimental investigations that are complementary to inhalation exposures with human subjects.     

高频脉冲管制冷机交变蓄冷器流动阻力特性实验研究——第一部分：研究现状及进展

总结了高频微型脉冲管制冷机蓄冷器交变流动阻力特性的研究现状.针对高频脉冲管制冷机设计过程中引用不同的流动阻力系数使得流动压力降结果相差很大的实际情况,系统总结了已有的研究成果,明确了不同经验公式和图表的适用范围,有利于提高高频脉冲管制冷机设计的可靠性.     

高频脉冲管制冷机交变蓄冷器流动阻力特性实验研究——第三部分：理论分析与实验结果

从基本方程人手分析交变流动蓄冷器,得到了不同于稳态流动的交变流动阻力系数定义,并在动态实验台的基础上,研究高频交变流动蓄冷器的阻力特性.实验中发现交变流动与稳态流动阻力系数的关系不能用简单的倍数关系表示,finst/fst比例因子随着瞬态雷诺数而变化;交变流动阻力系数随瞬时Re变化存在非对称性.所得实验结果对于高频脉冲管制冷机的整机数值模拟有重要的参考价值.     

RTNCSU: A COMPUTER PROGRAM FOR CALCULATING THE PARAMETERS OF THE CROSS FLOW FINITE STAGE MODEL FOR THE RESIDENCE TIME DISTRIBUTION IN TUMBLING MILLS FROM TRACER DATA

Based on a least squares method which searches for the best value of the parameters of the cross-flow finite stage model for residence time distributions in tumbling mills, a computer program package is presented for treating either open-circuit or closed-circuit tracer test data taken under various test conditions. The test conditions that are treated include the one and two detector approaches to closed-circuit tracer transient tests with optional perfectly mixed counting sumps in the mill input and/or mill discharge streams. The parameter search technique requires good initial estimates of the parameter values which are provided by the moments of the experimental data. This approach makes the program relatively straightforward to use. Simulated results demonstrating the use of the program are presented.     

高频脉冲管制冷机交变蓄冷器流动阻力特性实验研究——第二部分：实验装置和数据处理系统

鉴于目前高频脉冲管制冷机中蓄冷器交变流动阻力特性的设计数据十分缺乏,作者建立高频脉冲管制冷机蓄冷器的稳定流动和交变流动动态参数测量实验台,介绍了实验系统的组成、测试装置和数据采集与处理方法.实验台采用测控领域广为流行的LabVIEW图形化开发平台,将实验段两端的动态压力、流速数据等通过采集系统,送入计算机进行数据处理,并实时绘制图形曲线.通过测量蓄冷器两端的动态压力、流速,得到高频(30～60 Hz)交变流动情况下动态压力与质量流量之间振幅和相位关系,从而得到所测蓄冷器的交变流动阻力特性.