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11.
本文介绍在干旱地区建设的超临界间接空冷三塔合一大型散热设备的安装工艺,此工艺不仅提高散热设备吊装效率和安装质量而且缩短安装工期,达到降本增效的目的。 相似文献
12.
对于卷烟企业而言,生产环境的空气相对湿度是十分重要的参数之一,它直接影响着最终的产品质量。本文通过对等温、等焓加湿中几种常见加湿方式的优缺点进行比较分析,并结合卷烟厂车间生产工艺与负荷特点,提出了适合卷烟企业的加湿方式。 相似文献
13.
随着科技的不断发展,环境污染和能源损耗越来越严重,不利于我国的可持续发展。目前来说,国家大力倡导节能减排,减少资源浪费,而建筑环境设备会产生较大的能耗,不利于节能减排,因此有效控制建筑空调能耗和供暖能耗至关重要。研究表明,遮阳系数的大小对空调能耗产生较为明显的影响,而对供暖能耗产生的效果不是特别明显。因此,本文着重探讨遮阳系数对供暖与空调能耗影响存在的差异,希望能为同行提供一点参考。 相似文献
14.
Ioannis Karagiannis Panagiotis Vouros Antonis Skouloudis Konstantinos Evangelinos 《Business Strategy and the Environment》2019,28(7):1370-1405
Air travel is, nowadays, recognized as being one of the most popular modes of transport. Air transport is among the most significant contributors to the world gross domestic product and is accountable for a great environmental and social impact. Driven by the well‐established sustainability discourse and the vital role businesses can play in disseminating the sustainable development concept, this paper attempted to map airport industry's most material operational aspects and assess airport operators' accountability level on disclosing corporate information regarding airports' economic, environmental, and social performance. In this context, 33 reports and 903 material issues representing 193 international airports were reviewed and assessed, and a methodology for benchmarking the accountability level of best reporting airport operators was developed, showcasing materiality assessment as a useful management tool for strengthening airport operators' business strategy and enhancing their corporate performance. The paper indicated that (a) customer focus (i.e., health, safety and satisfaction), economic viability, and business continuity and preparedness are operational aspects of high materiality and (b) the disclosure level, especially concerning specific performance indicators, is still moderate. In conclusion, this study has shown that materiality assessment gains ground as a management tool among airports' management teams and the completeness of Sustainability reports is positively correlated with the “level” of adherence as described by the Global Reporting Initiative. 相似文献
15.
简要介绍了人防结构的设计特点,分析了关于等效静荷载的设计概念,并探讨几种人防结构构件上的荷载取值方法。 相似文献
16.
Matthew A. Cole 《Environmental and Resource Economics》2000,17(1):109-123
This paper examines the impact on air pollution ofchanges in the composition of manufacturing output indeveloped and developing countries. Pollutionemissions from manufacturing output are estimated ina manner which holds constant the effect of technologyand regulations allowing the impact of compositional changes alone on pollution to beestimated. The paper has three main findings; (1) theinverted-U estimated between per capita income and thepollution intensity of GDP arises due to both thecomposition of manufacturing becoming cleaner and theshare of manufacturing output in GDP falling.Compositional changes alone are not responsible forthe inverted-U between per capita income and percapita emissions; (2) changes to the composition ofmanufacturing output are consistent with the pollutionhaven hypothesis, however there is clear evidence thatrising per capita incomes are associated with afalling income elasticity of demand for `dirty'products. This fact may explain the compositionalchanges that occur with development; (3) in additionto the income elasticity effect, the analysis suggeststhat land prices and to a lesser extent the prices oflabour and capital, determine the proportion of dirtyindustry within a country's manufacturing sector. 相似文献
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汽车节能和排放环保的现状与发展趋势 总被引:4,自引:0,他引:4
文章介绍了由于计算机精确控制的、采用多气阀、高压直喷、稀薄燃烧等新技术的汽车发动机正在普及,现代电子控制装置在发动机上已全面应用,由此带来了油耗降低、排放污染下降显著的效果,并指出新型清洁能源车辆逐步走向实用,其相应的社会配套设施将形成一系列大有可为的全新行业。 相似文献
19.
The panel data analysis points to economic and social factors contributing to NOx, PM2.5, PM10, SO2, and VOCs in China’s 31 provinces. The spatial correlation analysis using Global and Local Moran’s I values indicates the existence of a significant and positive spatial autocorrelation with respect to environment, economy and energy, and the high spatial correlation is evident in the eastern region, covering the northern part of Yangtze River Delta, Huaihai Economic Zone, and the lower reaches of the Yellow River Economic Belt. The empirical estimation is performed through spatial lag and spatial Durbin models. All emitted air pollutants in 31 provinces have significant spatial dependence and strong spillover effects. There is an inverted U-shaped relationship between emitted air pollutants (NOx, PM10, VOCs, and PM2.5) and per capita GDP, which follows the EKC hypothesis. The relationship between SO2 and per capita GDP does not follow the EKC hypothesis. There is a positive relationship between pollutant emissions and coal consumption, which is consistent with current studies for various countries like Canada, Denmark, UK and US and regions like New York State. However, the effects of science and technology investment on air pollutants are mostly positive, which is not as policy expected. 相似文献
20.
射水抽气器影响汽轮机真空的原因及处理 总被引:1,自引:0,他引:1
针对一台25MW汽轮机组真空系统的特点,通过一次事故原因的查找,分析了因射水抽气器工作状况不良而引起的真空下降的原因,并提出了处理方法。 相似文献