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1.
根据斯涅尔定律和菲涅尔公式阐述清水衬底法消除玻璃下界面手印或玻纹的影像,以及用偏振光,紫外线拍摄玻面痕迹的方法和机理。 相似文献
2.
The present paper will outline the main aspects of the design and construction of cooling towers in Germany in the last decade. As part of electricity generating power plants, cooling towers play a significant role for the availability of reliable energy supplies, in a manner compatible with environmental requirements. They definitely belong to the largest and thinnest concrete structures at present. Because of the combined action of wind, thermal and moisture effects, special care has to be taken with regard to fatigue, cracking and corrosion to ensure an adequate level of safety and durability. Such a design strategy has been employed for the world’s tallest cooling tower at the Niederaussem power plant in Germany, with an overall height of 200 m and thickness values of 22–24 cm. Special considerations included the realistic non-axisymmetric distribution of soil characteristics, wind action due to interference effects (as determined by wind-tunnel tests), optimisation of the shell shape to improve structural and dynamic behaviour, injection of the cleaned flue-gas into the cooling tower, and the use of high-performance concrete (85 MPa) to improve shell resistance against acid attack by the cleaned flue-gas. The paper will present some results of an actual research project on this problem, which was conducted at the University of Wuppertal, to explore the use of high-performance concrete on design, stability and durability of cooling tower shells. 相似文献
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4.
我国煤炭生产的环境问题及其对策研究 总被引:4,自引:1,他引:3
论文分析了我国煤炭生产中所存在的环境问题 ,并提出采取应用全面绿色管理、贯彻实施ISO14 0 0 0系列标准及推广应用清洁生产等对应措施和方法。其中全面绿色管理是作者首次提出的全新概念。 相似文献
5.
The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD&T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD&T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. 相似文献
6.
从烟(粉)尘排放总量控制、大气污染物排放标准、清洁生产、中水回用、环境绿化和加强环境法制观念等方面,提出强化水泥建设项目环保设计和建设、促进水泥工业可持续发展的想法和建议。 相似文献
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8.
S. Vigneswaran H. Prasanthi H. B. Dharmappa 《Korean Journal of Chemical Engineering》1996,13(6):565-572
This study was aimed at investigating the effect of particle size, mostly in the submicron range, on break-through stage of
filtration. Latex beads, with diameters ranging from 0.46- to 2.967-μm were filtered through filter grains of diameters 0.1-,
0.175- and 0.45-mm. Experimental conditions were chosen so as to obtain breakthrough curves. The experimental results showed
that the initial efficiency follows the pattern reported by previous experimental and theoretical studies, i.e., lower efficiency
for 0.825-μm particles which fall in the range of critical size. However, the particle removal during the transient stage
increased with an increase in particle size for the range of sizes studied. This pattern is qualitatively confirmed by the
theoretical predictions of Vigneswaran and Chang (1986) model. This study also provides experimental verification of the effect
of the ratio of particle size and grain size at different stages of filtration. 相似文献
9.
钢中夹杂物的数量、尺寸、分布规律对钢产品质量有较大影响,因此,控制钢中非金属夹杂物是冶炼高品质洁净钢、提升产品品质的关键。通过对钢中非金属夹杂物性质、来源入手,分析了夹杂物碰撞、聚合长大、上浮及去除机理,同时对气泡吸附、电磁净化、过滤分离等夹杂物控制技术进行了对比分析,并对氧化物冶金技术发展现状进行了介绍。研究表明,气泡法与过滤法是以气泡和过滤器为媒介对钢水中夹杂进行吸附、捕捉并促进其进入渣相;电磁净化法借助电磁场离心力增加夹杂物碰撞、聚集长大的几率,但设备较为复杂,其应用受电力资源供给限制;夹杂物改性技术是将高熔点夹杂变性生成低熔点夹杂,促进夹杂物上浮,其操作简单,但容易造成钢水的二次污染。氧化物冶金技术通过改变夹杂物大小、形状和分布来钉扎和抑制高温下奥氏体晶粒的长大,避免粗大晶粒的形成,从而实现细化组织、提高钢的强度和韧性的目的。氧化物冶金技术为夹杂物的控制提供了新思路,具有重要的应用前景。 相似文献
10.
以Philips的89LPC936单片机作为智能化软硬件平台,综合超声波清洗,臭氧消毒,负离子保健等手段进行面部美容的新方法.实际运用表明,该方法能深入一般方法难以涉及的皮肤深层.加快新陈代谢,用于面部美容,起到了很好的作用. 相似文献