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81.
简述了我国燃煤电厂电除尘器的现状,概述了我国燃煤电厂电除尘器改造的一些主要技术路线,并重点分析了宝钢自备电厂电除尘采用高频电源结合本体扩容的改造案例。  相似文献   
82.
通过选取能够反映和体现泥石流危险性的8项重要参数指标作为泥石流危险性评价指标,运用物元可拓理论和熵值确定权重法,建立泥石流危险性评价的物元可拓模型。应用建立的物元可拓模型,对舟曲县15条典型泥石流沟的危险性进行评价,得到的评价结果与实际情况相符合,同时也说明基于物元可拓的熵值法能较真实地反映实际泥石流沟的危险性等级,证明该方法应用于泥石流危险性评价的有效性和可行性。  相似文献   
83.
Abstract: Modern global temperature and land cover and projected future temperatures suggest that tropical forest species will be particularly sensitive to global warming. Given a moderate greenhouse gas emissions scenario, fully 75% of the tropical forests present in 2000 will experience mean annual temperatures in 2100 that are greater than the highest mean annual temperature that supports closed‐canopy forest today. Temperature‐sensitive species might extend their ranges to cool refuges, defined here as areas where temperatures projected for 2100 match 1960s temperatures in the modern range. Distances to such cool refuges are greatest for equatorial species and are particularly large for key tropical forest areas including the Amazon and Congo River Basins, West Africa, and the upper elevations of many tropical mountains. In sum, tropical species are likely to be particularly sensitive to global warming because they are adapted to limited geographic and seasonal variation in temperature, already lived at or near the highest temperatures on Earth before global warming began, and are often isolated from cool refuges. To illustrate these three points, we examined the distributions and habitat associations of all extant mammal species. The distance to the nearest cool refuge exceeded 1000 km for more than 20% of the tropical and less than 4% of the extratropical species with small ranges. The biological impact of global warming is likely to be as severe in the tropics as at temperate and boreal latitudes.  相似文献   
84.
目的解决卫星伸展机构参数表现形式多样且不确定的问题。方法运用图示评审技术,构建MU-GERT网络模型,并将参数统一用广义灰数表征。考虑解析算法的复杂性,提出针对该网络模型的矩阵式表征方法,并设计出矩阵式求解算法,便于运用计算机编程进行准确快速的求解。结果用MU-GERT网络模型计算概率不确定时制作一个合格卫星伸展机构需要的时间,仿真模拟出制作出一个合格卫星伸展机构的期望与机会。结论为图示评审技术在卫星伸展机构研制中的应用提供了研究思路和经验借鉴。  相似文献   
85.
目的更为真实地反映自然贮存环境对某型导弹冲压发动机寿命的影响,研究综合环境应力加速贮存试验方法。方法为了符合自然环境的年变化规律,设计1个周期的综合环境应力加速贮存试验能够等效产品自然贮存1年,每个周期的加速贮存试验包括低温冷冻、高低温交变加速、高温高湿加速、高温老化4部分。采用加速模型估计出每段加速试验的加速因子,进而依据自然贮存环境测试数据折算出加速试验谱。结果所提方法提高了冲压发动机加速贮存试验的科学性与准确性。结论研究工作为高效完成导弹冲压发动机贮存延寿任务提供了可行的工程方法。  相似文献   
86.
可以从定性、定量两个角度解决问题的物元可拓法已被广泛应用于各个领域。选取具有代表性的BOD5、NH3-N、石油类、CODcr、粪大肠菌群五项指标为待评物元,取Ⅰ至Ⅴ类水质标准对应的取值范围构造经典域物元矩阵,按照污染贡献率法确定各特征的权重,应用建立的水质评价物元模型计算出关联度0.10,得出该污水处理厂出水环境质量属于Ⅲ级。研究表明,运用物元可拓集模型评价水环境质量具有可信性和实用性。  相似文献   
87.
Abstract

Lubei General Company of Enterprise Group, Shangdong Province, set up joint enterprises industrial ecosystem by sharing resources, symbiosis industry and compact structure. As an ecological Industry park, the industrial ecosystem has been operated successfully with rich experiment and has become one of ecological industry examples in the world. Based on the case study of Lubei ecological Industry project, components of industrial chains, matter recycle and conversion, energy cycle and multilevel utilization, systematic structure and impact factor identification are analyzed and summarized in this paper. The possible extension and development of Lubei ecological industry project in future is brought forward as well.  相似文献   
88.
利用“油田钻井废弃物无害化处理技术”,在塔里木盆地油田井区开展该项技术的适用性评估与示范推广,以实现油田钻井资源化、减量化及清洁化生产的目的。  相似文献   
89.
ABSTRACT: Providing adequate wastewater treatment facilities for the citizens in small rural communities in the United States can cost millions of dollars. An educational program has been developed and conducted in Ohio to teach local officials about wastewater treatment alternatives. The five-session workshop covers wastewater treatment principles, needs assessment, system management, and resource gathering. The knowledge and skills gained by the 96 community leaders who participated in six workshops were measured using a pretest/pest test and surveys conducted during the workshops. From 25 percent to 100 percent of the participants increased their knowledge of treatment systems, alternatives, and relative costs. From 23 percent to 84 percent applied new skills, such as conducting a sanitary survey or examining treatment systems. The pretest also revealed previous knowledge of the participants in the areas of system maintenance and consultant qualifications.  相似文献   
90.
Lubei General Company of Enterprise Group, Shangdong Province, set up joint enterprises industrial ecosystem by sharing resources, symbiosis industry and compact structure. As an ecological industry park, the industrial ecosystem has been operated successfully with rich experiment and has become one of ecological industry examples in the world. Based on the case study of Lubei ecological industry project, components of industrial chains, matter recycle and conversion, energy cycle and multilevel utilization, systematic structure and impact factor identification are analyzed and summarized in this paper. The possible extension and development of Lubei ecological industry project in future is brought forward as well.  相似文献   
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