IR Radiometry Optical System View Factor and Its Application to Emissivity Investigations of Solid and Liquid Phases

An optical system for fast IR radiometry designed for investigations of thin film thermal properties and pulsed laser melting was analyzed in this work. A methodology for determination of the view factor from calibration measurements was developed. The view factor (0.0255) of the optical system containing two paraboloid mirrors was determined experimentally from calibration measurements on pure metals and metallic alloys. The knowledge of the view factor was then applied to normal emissivity investigations at IR wavelengths. The emissivity of tungsten films prepared by magnetron sputtering was determined for different deposition conditions, varying between 0.036 and 0.071. Liquid phase emissivities of Cu, Mo, Ni, Si, Sn, Ti, and steel were also determined and were found to be higher than solid-state emissivities as predicted from the literature. A knowledge of the liquid-state emissivity of silicon enabled recalculation of the IR signal evolution to the temperature evolution, during and after a nanosecond laser pulse. This was not possible by use of the usual calibration because of silicon’s semi-transparent behavior in the IR range (1–10 μm) in the solid-state phase.     

基于边缘吸引力场正则化的短程线主动轮廓模型

短程线主动轮廓模型是近几年提出的一种有效的多目标轮廓提取算法 .本文在详细分析其动力学过程的基础上 ,针对该模型中存在的局限性和不足 ,提出对边缘吸引力场进行正则化的方法 ,并采用多尺度模型 ,有效的改善了该模型不能对存在断裂轮廓的目标进行正确提取和凹边缘搜索能力弱的缺点 ,增强了抗噪声和虚假边缘干扰的能力 ,使该算法具有更好的鲁棒性和实用性 .     

红外加热节能技术的现状与发展前景

本文综述了国内外节能的现状与发展趋势,论述了远红外电加热领域的发展前景,强调了加强基础理论研究的重要性,介绍了我国红外加热应用的领域和国外新开发的红外产品。     

Spectral Feature Analysis of Semiconductor Thin Disk Laser

The semiconductor thin disk laser is a new type of semiconductor laser. This work gives the basic operation function of the semiconductor disk laser, and analyses the heat effect by the experimentally measured photoluminescence spectrum of the laser chip at different pump power and different temperatures. We can see that: with increasing pump power, the thermal effect of the gain material becomes seriously and causes the saturation of carrier lifetime, so the electron-hole pair created in the absorbtion lay...     

某接收机测试台系统设计

介绍某接收机测试台设计方案、主要技术特点及实现方法。     

活性炭中甲烷水合物的生成动力学

在温度275．75－279．95K和压力5．6－9．6MPa的静置条件下，测定了14组甲烷水合物在活性炭中的生成动力学数据（压力－时间关系），分析了甲烷水合物在活性炭中生成的物理过程，结合边界层理论和结晶学原理，提出了单液膜传质控制机理的生成动力学模型，并求得了解析解,使用Levenberg-Marquardt方法拟合模型参数，模型预测值与实验值符合良好。     

锅炉炉膛红外成像温度实时检测系统研究

说明电厂锅炉炉膛温度及结焦直接影响锅炉正常运行及安全；给出了基于多探测器的锅炉反应温度红外成像实时测温系统的系统结构、系统原理、系统标定和温度测定方法。     

体积-表面淬火中加热温度的自动控制

根据表面-体积淬火奥氏体规范的要求，分析了感应加热过程中温度控制的特点和方式，并介绍了采用红外线光导纤维测温和微机控温技术成功用于体积-表面淬火中透热温度的自动控制。     

基于目录服务的跨平台账户管理

讨论了多重帐户问题在计算机网络管理中诸多弊端。提出以目录服务（Novell NDS）为基础，实现跨平台（NetWare、WindowsNT和Solaris）的帐刻统一管理的方案及详细实施实例。     

Studies on Catalytic Side-Chain Oxidation of Nitroaromatics to Aldehydes with Oxygen

The side-chain oxidation of 2-nitrotoluene in liquid phase in the presence of catalytic amount of manganese sulfate and stoichiometric amount of potassium hydroxide with oxygen was studied. In the most favorable conditions, over 80% of conversion of 2-nitrotoluene and 50% of selectivity to 2-nitrobenzaldehyde was achieved. Effects of the reaction parameters on the conversion of the reactant and the selectivity of the product were examined. These results, together with EPR spectroscopic study, show that a benzyl anion was formed in the early stage of the reaction, which was then converted to the final product via a free radical mechanism.