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71.
本文通过对立式旋风水膜除尘器除尘性能的模型试验,揭示了几个主要参数对其除尘性能的影响,确定了合理的取值范围,对该种除尘器的设计和应用提供了依据。 相似文献
72.
Venezuela's vast natural resource base has largely shaped the nation's economic and energy-use patterns. Major opportunities exist for improving the efficiency of energy use in Venezuela and, consequently, restraining the growth of energy-related carbon emissions. This paper presents a detailed report of one potential development path for Venezuela and estimates the ensuing levels of energy demand and CO2 emissions associated with pursuing this path through the year 2025. The results indicate that by adopting a development strategy that incorporates structural changes in the economy, fuel-switching measures and improved end-use efficiencies, Venezuela can introduce energy efficiency and carbon restraints as part of its economic development process. 相似文献
73.
火电厂实施废水零排放的可行性探讨 总被引:1,自引:0,他引:1
对合肥发电厂的用排水现状进行了介绍,并提出了实施废水零排放的可行性方案。 相似文献
74.
Myers Mark G.; MacPherson Laura; McCarthy Denis M.; Brown Sandra A. 《Canadian Metallurgical Quarterly》2003,15(2):163
The goal of the present studies was to construct and validate a short form of the 50-item Smoking Consequences Questionnaire (SCQ; T. H. Brandon & T. B. Baker, 1991), a measure of smoking outcome expectancies. In Study 1, a 21-item short form (S-SCQ) was derived from a sample of 107 young adults previously treated for substance abuse. In Study 2, the measure was cross-validated on 125 adolescents in treatment for substance abuse. Confirmatory factor analyses revealed good model fit and factorial invariance for the 4 S-SCQ subscales across both samples. Validation analyses on each sample found that subscale scores generally correlated significantly with smoking-related variables. The present studies provide initial evidence for the utility of the S-SCQ when used with young adults and adolescents. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Gerald Leach 《Energy Policy》1991,19(10):918-925
The UK differs from may other industrialized nations in that its carbon dioxide (CO2) emissions from energy use have declined in recent years despite relatively rapid economic growth. In all sectors but transport, substantial reductions have already occurred in the level of carbon emissions per unit of GDP output. At the same time, a number of official and unofficial studies have pointed out that the UK has one of the largest remaining potentials amongst comparable industrialized countries for achieving further CO2 reductions through the implementation of cost-effective energy efficiency and fuel switching measures. This paper discusses past and present patterns of energy use and carbons emissions in the UK. The analysis then examines historical trends in UK energy policy and presents policy options for further reducing the UK's energy-use and carbon emissions in the future. 相似文献
76.
77.
中国冷库的现状与发展趋势 总被引:8,自引:0,他引:8
张保生 《制冷与空调(四川)》2003,(2):21-24
本文从的设计建造、制冷工艺和管理维护这三个方面,介绍了近三年来中国冷库的现状,说明中国冷库正朝着灵活、自动化、节能和环保的方向进一步发展。 相似文献
78.
79.
The State of the Art in Text Filtering 总被引:1,自引:0,他引:1
This paper develops a conceptual framework for text filtering practice and research, and reviews present practice in the field.
Text filtering is an information seeking process in which documents are selected from a dynamic text stream to satisfy a relatively
stable and specific information need. A model of the information seeking process is introduced and specialized to define text
filtering. The historical development of text filtering is then reviewed and case studies of recent work are used to highlight
important design characteristics of modern text filtering systems. User modeling techniques drawn from information retrieval,
recommender systems, machine learning and other fields are described. The paper concludes with observations on the present
state of the art and implications for future research on text filtering.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
80.
针对UO_3的N_2还原反应建立了多孔挡板流化床反应器模型。将多孔挡板床的每一级视为具有相似的流动状态,每一级的上、下段称为稀、密相段,分别用鼓泡床和活塞流模型描述。该模型的计算值与¢63mm的多孔挡板床H_2还原UO_3的热态实验值能较好的吻合。还预计了还原温度、操作气速和挡板结构参数对固相转化率的影响,为该类反应器的工业设计、放大和优化提供了依据。 相似文献