Optimization algorithm for the pump structure of diode side-pumped solid-state lasers

The pump structure greatly influences the characteristics of a diode side-pumped solid-state laser (DSPSSL). To achieve high absorption efficiency and a homogeneous pump-beam distribution simultaneously, a systemic algorithm has been established to optimize the pump structure, where multiple reflections occur on the internal wall of the reflector inside the pump chamber. The absorption efficiency and the deviation of the absorption distribution are both evaluated for a typical solid-state laser medium. A scheme for identifying an ideal pump configuration was finally obtained from several determination procedures, in which all pump structure parameters were taken into account. The experimental results demonstrate that the approach described in this paper is effective for the design of DSPSSL systems with both high output power and good beam quality.     

Some new examples of Markov processes which enjoy the time-inversion property

In this paper we give a sufficient condition on the semi group densities of an homogeneous Markov process taking values in ⁿ which ensures that it enjoys the time-inversion property. Our condition covers all previously known examples of Markov processes satisfying this property. As new examples we present a class of Markov processes with jumps, the Dunkl processes and their radial parts.Mathematics Subject Classification (2000): 60J25, 60J60, 60J65, 60J99     

Simulation on the response of new phosphate glass RPC for <Emphasis Type="Italic">γ</Emphasis>-rays and e<Superscript>+</Superscript>/e<Superscript>−</Superscript> particles using GEANT3

The influence of phosphate glass electrode in the configuration of resistive plate chamber has been studied using GEANT3.21 Monte Carlo code. Bakelite electrodes were replaced by phosphate glass electrodes, as these glass materials have low bulk resistivity, are portable and easy to handle. These types of RPCs in their compact form of all materials are suitable for high rate background environment. We find that these new types of RPCs give little higher response to γ-rays and e⁺/e⁻ particles, both for single-and double gap RPCs. The results of simulation are discussed.      

Resistive plate chambers for muon detection at LHC

One resistive plate chamber made of Chinese materials and one Italian resistive plate chamber have been tested in the Gamma Irradiation Facility (GIF) at CERN on a high intensity muon beam together with a¹³⁷Cs source to give a uniform photon background, and simulating conditions close to those expected for an LHC muon detector. The results are analyzed. Good space and time resolutions are obtained which satisfy the future CMS experiment requirements. The detection efficiency is different between two RPCs against a high irradiation background. The reason is discussed.     

上海同步辐射装置储存环注入冲击磁铁的设计

 开展了上海同步辐射装置储存环注入冲击磁铁的结构和脉冲电源的技术设计,并进行了磁场分布和励磁电流波形的模拟计算。还给出了陶瓷真空盒镀膜的设计参数,提出了计算陶瓷真空盒镀膜接受同步光功率的公式,研究了防止镀膜和波纹管受到同步光照射的机械布局设计。     

水平井蒸汽辅助重力驱油藏模拟方法

研究了油藏与水平井段耦合的蒸汽辅助重力驱整体模拟的数学模型及其求解方法.将研制的沿水平井井筒方向有质量、能量损失的一维多相管流模块与油藏模拟主体软件集成,能预测水平井蒸汽辅助重力驱蒸汽腔室的大小及形状的动态变化.通过模拟计算分析了毛管力、蒸汽干度、地层深度等对蒸汽腔室发育程度的影响,并取得了结果.     

ITER中子通量监测器原型的研制

研制的用于国际热核实验堆(ITER)的中子通量监测器由裂变室探测器组合构成,包括两只不同     

Dynamic Vapour Generation and Head Space Determination of m-XYLENE for Pharmacokinetic Studies

Abstract

A custom designed vapour generation-exposure chamber assembly and head space analysis method were evaluated for use in pharmacokinetic investigations. The predicted m-xylene concentration was within 1% of the average value measured by gas chromatography-flame ionization detection (GC-FID) in the glass exposure chamber during controlled vapourization of m-xylene. The concentration variability was ± 13% and 4% respectively, with and without rats in the chamber. Blood and tissue samples from male, Sprague Dawley rats exposed to 1100 ppm of xylene, were analyzed by means of a static head space (HS)-GC analysis method. The average m-xylene level in the blood of exposed animals was ca. 5000 ng/mL. m-Xylene was detected in brain, kidney, skin, fat and liver. The analytical precision for duplicate samples was < ± 5% for all tissues, except liver and skin. The feasibility of detection of m-xylene in unhomogenized tissue by HS-GC analysis was demonstrated.     

Multi-purpose explosion chamber with sound muffling and vibration cutting means

Abstract

An explosion chamber is operating for more than 13 years successfully. The chamber is used for procucing wBN powder and various dynamic high pressure experiments. The capacity of the chamber is 200 cubic meter by volume and 10 kg by the quantity of the explosives to be exploded. Safety means are equipped sequentially, transmitted sound level is less than 65 db at 60 m point from the chamber and earth vibrations cannot be detected at its periphery. The strength of the chamber was designed by simple static gas pressure model.     

新型光离子化检测器的设计与应用

将自行研制的PID光离子化检测器安装于气相色谱仪上,无需复杂的样品前处理,便可快速分析环境中的苯系物、醛类等物质.概述了此检测器的基本原理,详细介绍了其结构、电路系统的设计及性能测试结果.采用喷嘴与电极一体化的设计理念,使电离室的体积缩小到30 μ L,灵敏度提高,同时易于加工；微电流放大器的设计选用低噪声、低温漂的精...