托卡马克等离子体杂质密度的光谱法测量研究

本文介绍了基于托卡马克等离子体被动光谱诊断获得杂质密度的方法。通过被动光谱诊断测量获得杂质线辐射的空间多道弦积分强度分布,利用强度标定系数转换为绝对光亮度分布;通过测量弦与等离子体位形,将弦积分的强度分布反演变换为径向体发射率。根据线辐射强度激发截面求出对应电离态的离子密度,最后采用杂质输运程序模拟计算得出总密度分布。以东方超环(Experimental Advanced Superconducting Tokamak,EAST)托卡马克装置上软X射线-极紫外光谱(Soft X-ray and Extreme Ultraviolet Spectrometers,XEUV)诊断测量到的Mo XXIX-Mo XXXII为例,描叙了获得Mo杂质密度分布的过程,获得的总误差小于10%。     

基于前置反射器的多波长铸坯表面测温方法

钢铁冶金现场的连铸铸坯表面温度是重要的工艺参数,针对铸坯表面温度难以测量,研究一种前置反射器与多波长结合红外辐射测温方法,该方法分别建立有反射器和无反射器的多波长辐射能量方程,在线求解被测铸坯表面的发射率和铸坯表面温度。利用蒙特卡洛方法建立铸坯表面的多层模型和光波的多次反射-吸收的仿真模型,模型分析表明该方法可实现准确的铸坯表面温度测量。     

Variable emissivity infrared electrochromic device based on polyaniline conducting polymer

The use of polyaniline (PANI) as active layer in the electrochromic (EC) devices operating in the mid-infrared (mid-IR) ranges (3–5 μm, 8–12 μm) was investigated. The optical properties of the device were characterized by spectrophotometry in the wavelength range from 0.4 μm to 15 μm. Results show that upon reversible doping and undoping, the devices yield an average emissivity dynamic range of ca. 0.24 in the 8–12 μm region. The lowest emissivity of the devices in this region can be adjusted from 0.4 to 0.68 according to the preparation conditions. The average reflectance dynamic range is 18% in the 3–5 μm and 34% in the 8–12 μm regions.     

Investigation about the effects of exterior surface paint color on temperature development in aboveground pipeline

A practical analytical model for predicting temperature development of incompressible flow inside an aboveground pipeline has been constructed and presented in this research work. The outer surface of the pipeline is exposed to solar radiation and wind stream. The radiation heat exchange with ambient is also taken into account. The effects of exterior surface paint color represented by emissivity and absorptivity, have been studied. The model has been developed to study crude oil flow temperature development through a specific pipeline. The results obtained by the model show that the bulk temperature inclined to a limiting value in some distance which affected mainly by Reynolds numbers. It is found that emissivity and absorptivity of surface are predominant parameters in temperature development in an aboveground pipeline flow which can increase or decrease pipe surface and fluid temperature especially for low Reynolds number flow. Based on the results which indicated significantly of exterior surface paint color, one should choose the paint color by considering its effects on temperature development.     

Nano-thermal transport array: An instrument for combinatorial measurements of heat transfer in nanoscale films

The nano-Thermal Transport Array is a silicon-based micromachined device for measuring the thermal properties of nanoscale materials in a high-throughput methodology. The device contains an array of thermal sensors, each one of which consists of a silicon nitride membrane and a tungsten heating element that also serves as a temperature gauge. The thermal behavior of the sensors is described with an analytical model. The assumptions underlying this model and its accuracy are checked using the finite element method. The analytical model is used in a data reduction scheme that relates experimental quantities to materials properties. Measured properties include thermal effusivity, thermal conductivity, and heat capacity. While the array is specifically designed for combinatorial analysis, here we demonstrate the capabilities of the device with a high-throughput study of copper multi-layer films as a function of film thickness, ranging from 15 to 470 nm. Thermal conductivity results show good agreement with earlier models predicting the conductivity based on electron scattering at interfaces.     

High emissivity coatings for high temperature application: Progress and prospect

High emissivity coatings are widely used in many cases where heat transfers through electromagnetic radiation that arises due to the temperature of a body. Extensive theoretical and experimental efforts have been made to synthesize and investigate high emissivity coatings. The emissivity can be improved through various or combined mechanisms. The characterization of the emissivity is still a fully open problem. In this paper, we review the various mechanisms associated with the emissivity enhancement and emissivity characterization techniques. Based on these literature reviews, the prospect will be presented in the concluding remarks.     

星载微波辐射计定标热源研究

介绍了应用频率在10~90 GHz波段的星载微波辐射计定标热源的结构及其功能;论述了定标热源微波吸收材料选择、吸收体结构设计、热设计及温度测控等技术与方法;给出了定标热源吸收率和温度特性测试结果。地面和在轨运行均表明,该定标热源满足星载微波辐射计设计要求。     

一种在8—12μm波段高发射率涂料的研制

影响目标红外辐射亮度有两个因素：表面温度和发射率。运用涂料是改变发射率的一种简单可行的方法，使用不同发射率的涂料能够灵活有效地使目标热变形，达到隐身的目的。我们研制的一种高发射率涂料（ＦＨ９４－１型）由粘合剂、着色染料、填加剂配制而成。用红外光谱仪测得该涂料在８￣１２μｍ波段有较强吸收特性，这种吸收特性主要来自填加剂。使用ＡＧＥＭＡ９００热像仪，测得８￣１２μｍ波段法向平均发射率εｎ等于０．９２。     

改进测量方法目标真温的测试

本文进一步指出在利用红外测温仪测量低温物体的温度时,除进行目标的比辐射率修正外,还必须进行等效环境辐射温度的修正,并给出了更为客观的实验验证。同时,本文也给出了一种实验室评估测温仪性能新方法。     

典型地表对长沙主城区地表温度的影响分析

城市热岛是一种城市地区温度比郊区温度高的现象,它可改变城市的自然和社会过程,引发一系列环境问题.利用Landsat 8 TIRS10波段的单通道算法(TIRS10_SC算法)反演了长沙主城区2013年7月、2016年3月、7月和11月4景Landsat 8影像的地表温度,并进一步分析了地表温度的时空分布特征,建设用地、...