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161.
着色型珠光颜料涂布纸的研制 总被引:1,自引:1,他引:0
本文论述了着色型珠光颜料涂布纸的研制工作,并对影响珠光涂料制备的几个因素进行探讨.优化结果表明,瓷土0~30%,珠光颜料70%~100%,胶粘剂25%~30%,固含量23%~25%,涂布量10~15g/m2时,其纸面呈现强烈的珠光光泽,适用于胶印. 相似文献
162.
Measurements of the thermal diffusivity of thin films on substrate have been performed by the photoacoustic method. In order to examine the method we have built a new apparatus and proposed (1) a system calibration procedure using optically and thermally thick reference samples and (2) a data analysis procedure based on the RG (Rosencwaig and Gersho) theory. As a result of using a transparent photoacoustic cell, the systematic errors which are caused by stray light have been reduced. With this apparatus, measurements have been performed on platinum, titanium, and stainless steel (SUS304) thin foils (thickness form 50 to 100 µm) with three different liquid backing materials (water, glycerol, and ethyl alcohol). The reproducibility was within ±7% regardless of film thickness and substrate materials. 相似文献
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164.
热力系统节能技术改造方案介绍 总被引:3,自引:0,他引:3
针对热电厂热力系统存在的浪费能源和设计不合理现象作了浅析 ,介绍了几种对热力系统进行改造的方案 ,并对取得的经济效益进行了计算。 相似文献
165.
Four epoxy film adhesives used in aircraft manufacture and repair have been examined to establish the effect of deviation from the cure cycle specified by the manufacturer. In addition to the variation of the cure cycle, two surface preparations of the aluminium adherends (chromic acid etch or grit blast followed by silane treatment) were evaluated. Thermal analysis was used to examine the cure envelope of the adhesive, and its extent of cure and glass transition temperature. The adhesive properties were assessed by shear strength (in both single lap joints and in Iosipescu configuration), durability (Boeing wedge test) and chemical resistance to selected aggressive fluids. The sensitivity of the performance of a particular adhesive to offoptimum cure conditions depends on its composition and needs to be determined, not predicted. 相似文献
166.
为了研究压水堆因“直接安注”冷水注入压力容器下降环腔而导致的承压热冲击(PTS)热工水力问题,基于1:10比例模型,应用计算流体力学软件FLUENT5.4进行了紊流流动换热的数值模拟分析,同时进行了常压瞬态传热实验研究。针对下降环腔折算流速0.5 m/s,安注流速10m/s的典型工况,研究了安注水开启后下降环腔内的瞬态流动换热特性,数值模拟与实验结果吻合良好。考察了压力容器安注接管出口区环形焊缝区及堆芯段筒体中子强辐照区所承受的热冲击状况,基于稳态流动研究了下降环腔内流体混合特性及流动机理,为热冲击分析提供参考。 相似文献
167.
Optical measurements of thermal diffusivity of a material 总被引:2,自引:0,他引:2
The measurement of thermal diffusivity of a material (in particular, a thin film) is important for various reasons, e.g., to predict the heat transfer in the solid subjected to a thermal process, to monitor surface composition or morphology, or to detect invisible subsurface defects like delaminations. This measurement can be done in a noncontact manner using various photothermal methods. Such methods typically involve pulsed heating of the surface by small amounts using a laser source; the decay of the surface temperature after this pulsed photothermal heating is then probed to provide the thermal diffusivity. Various probing methods have been developed in the literature, including the probing of reflection, refraction, and diffraction from the pulsed heated area, infrared thermal radiometry, and surface deformation. This paper provides an overview of such techniques and some examples of their applications. 相似文献
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170.
L.J. Webb 《Water research》1985,19(8):969-974
Wastewaters from the manufacture of pulp and paper have given rise to problems of excessive microbial growth in rivers over a number of years. This paper is the first in a series of four articles describing research undertaken by PIRA at four U.K. paper/board mills (one integrated with pulp production) over the period 1978–1980. This first paper briefly reviews the published literature on sewage fungus growth from pulp and paper mill discharges up to 1978, but mainly describes previously unpublished work undertaken by PIRA over the period 1965–1975. This introductory paper thus provides a state-of-the-art review of methods to control sewage fungus growth from pulp and paper mill effluents prior to commencement of the research described in the following three articles. 相似文献