共查询到20条相似文献,搜索用时 46 毫秒
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柴油车凭借其高燃油比,经济耐用和高安全性具有广泛的发展空间,但柴油车尾气中高含量的碳烟颗粒,极大的危害了环境和人体健康。催化再生过滤技术能有效去除柴油车尾气中碳烟颗粒,其核心是开发高性能碳烟燃烧催化剂。碳烟燃烧催化剂可有效降低碳烟燃烧温度,实现柴油机尾气中碳烟颗粒物的去除。文章介绍了尾气中碳烟颗粒物的形成与控制技术等概况,综述了不同种类碳烟燃烧催化剂的主要研究现状。 相似文献
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采用羟基铂酸为前驱体,通过沉淀转化工艺制备了铂担载量为20%(质量分数)的碳载铂催化剂。通过该方法制备得到的催化剂中纳米铂颗粒的粒度细小均一(约2~9 nm)、在载体上分布均匀、杂质Cl-含量少。质子交换膜燃料电池(PEMFC)单电池测试表明,该方法制备的催化剂对H2氧化的催化性能与E-TEK商品催化剂相当,最高输出功率密度达到1.34W/cm2。 相似文献
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电脑数显碳硫分析仪型号为HV -4B ,采用MCS— 5 1系列单片微机完成化学流程的控制以及模拟滴定分析过程 ,8只防腐电磁阀作为仪器的气路和液路通断开关 ,碳的测定采用气体容量法 ,由高灵敏度的气压传感器检测结果 ,微机自动进行数据处理 ,硫的测定采用碘量法注射式滴定。与仪器配套使用的有高速自动引燃炉、电子天平。整个设备操作方便 ,分析速度快、精度高 ,读数自动化。故障描述 :设备正常使用时 ,一般先做 3个废样 ,再做标样 ,最后做试样。 2 0 0 3年 3月在做前 3个废样试验时 ,碳含量有数据显示 ,硫含量一直没有数据显示。由于设备不… 相似文献
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三氯氢硅的合成过程中会引入碳杂质,在多晶硅和作为硅源的硅外延片生产中很容易发生沉积,形成晶格点缺陷,从而影响半导体材料的性能。高纯三氯氢硅中碳杂质主要以甲基二氯硅烷形式存在,而甲基二氯硅烷沸点与三氯氢硅接近,依靠单纯的精馏法很难去除。文章重点介绍普通精馏法、吸附法、反应精馏法等几种三氯氢硅除碳方法,经过对比分析,精馏与树脂吸附相结合是目前比较有效的三氯氢硅除碳工艺。 相似文献
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Vidosav Tričković 《Food Policy》1976,1(4):320-332
Nutrition should be seen as an integral part of the national planning effort. The author examines longterm determinants of food consumption in developing countries and shows that progress in improving nutrition is closely related to raising productivity and efficiency in the national economy. Optimum programmes in nutrition should be part of the design of appropriate social and economic development. This should be done at national and regional levels, with particular emphasis on the regional level. 相似文献
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1997年5月,笔者受当时的冶金部部长刘淇的委托,带领扭亏调查组到舞阳钢铁公司(以下简称舞阳),参加企业扭亏工作。当时,舞阳已经连续4年严重亏损,虽然1995年6月,冶金部调整了舞阳的领导班子,生产经营形势有了一定好转,但并没能扭转亏损局面。1996年,全国工业企业超亿元的亏损大户共14个,冶金系统占了6个,舞阳就是其中之一。在调查工作的后期,刘淇部长也来到舞阳,听取了调查组的汇报,对舞阳下一步的工作提出了明确要求,并且宣布了部党组的决定,调邯钢总经理助理顾强圻为舞阳钢铁公司的副总经理,协助林承模总经理负责全面工作。同年9月,舞阳实行改制,并入邯钢集团,顾强圻出任舞阳的总经理。目前,顾强圻担任舞阳代理董事长、党委书记。 相似文献
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Roger N Payne Mike D. Bramhall J. Steve Lawson Ian Robinson Chris Short 《International Journal of Technology and Design Education》1993,3(3):37-42
Summary A portfolio assessment scheme, introduced for one course in 1990 in the School of Engineering, Sheffield Hallam University is proving to be both a stimulus and support for change. The scheme is described and its impact discussed in terms of staff development, the student experience and curriculum development. 相似文献
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Gregory Schmid 《Food Policy》1976,1(3):220-231
The potential food deficit in many developing countries creates opportunities for foreign commercial investment in food production. The factors influencing the profitability of such investment — agricultural, economic, social, political and investment factors — are examined in this article. Dr Schmid has used these five factors to identify a number of countries where the potential for profitable investment is high. He illustrates the range of good investment opportunities by describing the potential of eight countries — Argentina, Brazil, Columbia, Pakistan, Thailand, Kenya, the Malagasy Republic and the Sudan. 相似文献
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Suppliers in business markets are increasingly providing complex offerings, which is reflected in concepts like hybrid offerings, servitization and solution business. Such complex offerings are characterized by value propositions in which the value that emerges throughout the entire customer usage cycle builds the core element. To secure and increase this value in use, as perceived by the customers, suppliers need to establish activities of value-in-use management. This value-in-use management comprises monitoring the delivery of the promised value, and enhancing customer value in use throughout the entire lifecycle of a complex offering. This article investigates which value-in-use management activities are currently implemented by suppliers, how these activities are linked to other business processes, and what differences in value-in-use management activities exist between various types of complex offerings. By addressing these questions, this research contributes to literature by exploring post-deployment processes that affect value in use customer experience when using complex offerings. Moreover, from a managerial perspective, it reveals in which constellations measures of value-in-use management are currently implemented in practice and therefore are of particular importance. Furthermore, the results of the study may serve as a starting point to elucidate how measures of value-in-use management can be implemented successfully. 相似文献
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我国生物柴油产业发展应注意几大问题.第一,在预测生物柴油产业的发展前景时,应对我国现有的和可适度种植的生物柴油资源进行实事求是的分析和科学的统计.对于植物原料,应全面发展油料树木,兼顾生物多样性,科学统计原料数量.对于废弃油脂,应建立法规体系,把废弃油脂的产生、收集、处理流程统管起来,形成一个完整的产业链,同时推广一批新技术.第二,应协调处理好三大石油公司之间,三大石油公司与民营企业、其他国有企业和外资企业之间的竞争与合作关系.第三,应尽快出台生物柴油国家标准.此外,应将生物柴油作为资源性产品,限制出口;利用三大石油公司在炼油和石油设备制造方面的有利条件,尽快形成我国生物柴油的技术优势和设备制造优势;坚持国家对生物柴油产业实行的非直接补贴的财政扶持方式;正确看待油价波动对我国生物柴油产业的影响,兼顾生物柴油的设备制造业和技术服务,从而使生物柴油这个横跨一、二、三产业的行业健康发展. 相似文献