共查询到20条相似文献,搜索用时 390 毫秒
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苯并二氧杂环类化合物存在于天然产物中,具有很好的生物活性,文献报道苯并二氧杂环类化合物可作为医药应用(CA,1990,113:52534);另有文献报道苯并二氧杂环类化合物具有很好杀虫活性(Bull.Soc.Chim.France,1964,1892).专利EP1048664报道了以4-羟基苯基乙基酮为原料,制备5-丙基苯并1,3-二氧杂环的方法. 相似文献
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介绍脱盐水站的扩能改造.为提高脱盐水站的水质和处理能力,将一级制水工艺改为二级制水工艺,并将固定床离子交换器改为双室固定床离子交换器.出水达到二级处理质量指标,并可满足废热锅炉及HRS系统的用水要求.对运行中存在的问题进行了分析并提出改进建议. 相似文献
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火电厂石灰石粉/石膏法脱硫需要高质量的石灰石粉并产生脱硫石膏副产品;水泥厂能生产石灰石粉并消耗大量石膏.电厂和水泥企业可互通有无.水泥企业生产生料的立磨,完全可以生产符合电厂脱硫吸附剂质量要求的石灰石粉,并达到节能目的. 相似文献
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阐述了项目管理已经应用于现代管理的各个领域,并向全球化、多元化、专业化发展.并对我国项目管理的发展提出建议. 相似文献
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为了提高通用聚丙烯的刚性和热变形温度,通过剖析市场上深受用户欢迎的一种进口南韩的高刚性高结晶聚丙烯(PP)的产品,对照茂名石化现有PP产品,找到性能相近的一种PP产品进行改性,改性产品V30K与进口大韩油化均聚HJ4012性能相当,产品V30K顶替进口产品HJ4012顺利进入市场,深受用户好评. 相似文献
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介绍了一种以新型高温混合材料作为铠装热电偶的绝缘材料,通过大量试验验证了封装后的热电偶传感器具有较高的测量精度、长期热电势稳定性、高绝缘性和较短的热响应时间,能够满足高温、高响应性测量要求。在1 000℃的情况下测量,其性能不亚于以氧化镁作为绝缘材料的产品,因此可应用于工业生产和科学研究中。 相似文献
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A variant of the Vienna DMA (Winklmayr et al. 1991; Reischl et al. 1997) with inner and outer electrode radii of 25 and 33 mm, and a conventional trumpet inlet diameter of 97 mm has been tested. It incorporates a reduced pressure drop sheath gas exhaust system that enables reaching flow rates approaching 4000 L/min. Several new additional flow features are included to delay the transition to turbulent conditions. A cylindrical geometry with a DMA length L of 97 mm (distance between the aerosol inlet and outlet slits) is seen to keep the flow laminar up to the highest Reynolds number achieved, though showing slight signs of flow quality deterioration at about Re = 20,000. An equally long DMA with an inner electrode shaped as a 5° cone caped by a spherical dome remains stable up to the highest Reynolds number achieved. It is expected to continue this trend to considerably higher flow rates. Both these long configurations exhibit line widths close to the ideal Brownian diffusion limit, reaching FWHH of 4% for a particle mass diameter of 1 nm. A short DMA with an axial length L of 18 mm and an inner electrode shaped as a 5° cone caped by an ellipse of 3/2 aspect ratio remains also laminar at the highest speeds attained, and exhibits FWHH as small as 2.4%. It departs moderately from ideal behaviour at small flow rates, presumably due to its non-cylindrical geometry. More serious departures observed at high Reynolds numbers may perhaps be due to flow unsteadiness radiated into the working section by sound waves from the turbulent exhaust region. This is the first report of a DMA capable of excellent resolution at 1 nm, yet with a sufficiently wide and long working section to enable (in principle) covering the size range up to 100 nm. 相似文献