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51.
文章从战略环境影响评价的概念和分类进行分析,结合我国战略环境影响评价的当前发展,对战略环境影响评价在我国经济发展中的意义和必要性进行研究。结合其对经济发展和地区规划的影响等多方面的分析,提出战略环境影响评价所遵循的原则和评价程序,并对其评价程序进行分析和论证,进一步论述了战略环境影响评价的意义。  相似文献   
52.
Sustainability issues in sheet metal forming processes: an overview   总被引:1,自引:0,他引:1  
Environmental sustainability in manufacturing is nowadays an urgent and remarkable issue and the main concerns are related to more efficient use of materials and energy.In sheet metal forming processes there is still a lack of knowledge in this field mainly due to the need of a proper modelling of sustainability issues and factors to be taken into account. The aim of this paper is mainly to underline the state of the art from a forming point of view about the sustainability contributions offered in any phase of a product life cycle. Actually, a lack in terms of comprehensive contributions is present in the technical literature, thus, the authors try to give a sort of holistic vision aimed to provide basic guidelines in order to help in identifying the possible solutions with regard to all the phases of a forming product life cycle. The main attention was paid to sheet metal forming technologies. The paper gives an overview of the main topics concerning sheet metal forming problems related to energy and resource efficiency with the aim to stress the principal contributions which may derive from such processes to environmental performances of manufacturing.  相似文献   
53.
Hazardous chemicals are pervasive in household disinfectant products. Many ingredients have established associations with acute and chronic human health conditions as well as with environmental damage. Although these associations are suggested but not proven, they are of great concern. This article describes the application of the precautionary principle to the selection of an anti-microbial active ingredient for a botanical disinfectant when significant uncertainty exists around the hazard and risk of traditional disinfectant active ingredients. We show that application of the precautionary principle does not stifle innovation and facilitates a responsible approach to product development.  相似文献   
54.
云贵高原湖区湖泊营养物生态分区技术方法研究   总被引:2,自引:1,他引:1  
提出一种基于主成分分析、聚类分析、判别分析和空间自相关的分区模型,用于对云贵高原湖区湖泊营养物生态分区的研究.首先运用主成分分析方法对众多指标进行了降维综合处理,产生彼此互补相关又能综合反映湖区情况的4个新指标,累计贡献率达到93.69%,具有充分的代表性,构建了云贵高原湖区湖泊营养物生态分区指标体系.在此基础上,根据各区域新指标值,结合聚类模型初步将湖泊流域分为5类,再利用判别分析完成非湖泊流域的类别判别,最后运用空间自相关分析方法,按聚类结果进行全局自相关分析,Moran’sI为0.320,且检验值Z值为68.2,远大于临界值(显著水平1%所对应的临界值2.58),表明聚类结果与空间位置具有显著相关性,之后运用局部自相关对区域各因素的主成分综合得分的空间分布格局进行了量化分析,揭示了零散分类区块在空间地域分布上的关联和差异,根据关联结果完成最终的分区.结果表明,利用此分区模型可以尽量避免人为因素,得到更为客观的分区结果,具有良好的适应性和可行性,可为探索适合我国湖泊营养物生态分区的指标体系和分区技术方法,完成全国湖泊营养物生态分区和科学地制定我国湖泊营养物基准和富营养化控制标准提供技术支持.  相似文献   
55.
概述了含油废水的来源、特点、分类及危害,介绍了含油废水的处理方法的原理、优势及存在的问题,同时简述了各种处理方法的最新研究成果,最后提出了含油废水发展趋势。  相似文献   
56.
The majority of the research activities in the area of warm forming are concentrated on demonstrating or simulating the improved formability associated with forming lightweight materials such as aluminum alloys at elevated temperatures. However, the ability to design the proper thermal management system within the forming tool is a critical aspect to delivering this technology as a viable, stable production alternative to traditional stamping. This work begins to address the thermal stability issues of this process by examining the impact of process cycle time on the parting surface temperature response. Cycle times of 10, 15, 30, and 300 s were evaluated using a reciprocating surface and a self-heated experimental block of 1020 steel fitted with resistance cartridge heaters. The presented results indicate that cycle time does not significantly impact the steady-state temperature response at the parting surface for a well-insulated die that has proper thermal management. Parting surface experimental results were compared to values obtained numerically and through the use of the novel thermal finite element analysis software PASSAGE/Forming®.  相似文献   
57.
随着全球环境问题日趋严重,企业和消费者日益认识到减缓气候变化的紧迫性。作为经济活动的主要参与者,减少温室气体排放已经成为任何单个企业及其供应链的巨大挑战。供应链的所有参与者都需要为气候减缓做出努力。现有的碳排放责任核算大多从企业的生产方面入手。最终消费者作为供应链的重要参与者,是所有生产者的最终服务对象,同样具有不可忽视的碳减排作用以及应承担的碳减排责任。本文提出以产品为导向,考虑产品生产过程中的直接碳排放和间接碳排放,建立产品碳排放基准值,对基于供应链的所有参与主体进行责任分配,进而建立基于供应链的碳责任账户。本文构建的责任体系框架具有更广泛、更有前景的应用潜力。  相似文献   
58.
沟谷泥石流运动过程模型试验   总被引:2,自引:0,他引:2  
泥石流运动过程是泥石流运动力学核心内容之一.以新疆天山公路K630泥石流为原型,选取几何相似比1:650,推导了泥石流质量、固液两相流速和泥石流冲击力相似比,以流通区为核心,建造了沟谷泥石流试验模型.试验结果表明,泥石流运动具有显著的阵流特性,阵流间隔时间为10s左右,其间嵌套2~3次弱阵现象;阵流期间,泥石流流速和冲击力均较大;从流通区的源头至沟口,流速呈现非线性增大趋势,且泥石流体中固液两相流速变化趋势相似,弯道处泥石流超高现象显著;泥石流运动初期由于泥石流体中固相和液相混和搅拌不均匀而呈现稀性泥石流特征,随后粘性特性增强.这些现象与现场观测结果基本一致.  相似文献   
59.
Irnazaquin applied in legume crops has a long residual time in soil, which often impacts safety of the susceptible crops. To increase safety of imazaquin application, two composted litters, bovine manure (BM) and chicken manure (CM), were used to determine their effects on imazaquin environmental behavior by incorporating each kind of manure into the tested sandy loam soil at 10% (w/w). The degradation of imazaquin in BM- and CM-amended soil was about 2.4 and 1.5 times, respectively, faster than that in unamended soil. The half-lives of imazaquin in BM-amended soil varied between 6.7 and 15.4 d over the temperature range of 20 to 40℃, and the degradation rate constant (k) increased by a factor of about 1.5 for every 10℃ change. Higher mix ratio did not significantly increase the degradation, and the optimal active degradation of imazaquin was observed approximately at the mix ratio of 10:1 of soil to BM. The different moisture levels had negligible effect on imazaquin degradation. In both unamended and BM-amended treatments, two metabolites were observed at 5, 10 and 30 d after treatment. One metabolite at retention time (RT) of 8.4 rain was identified as 2-(4- hydroxyl-5-oxo-2-imidazolin-2-yl) quinoline acid, originating from the loss of isopropyl group and hydroxylation at the 4-position of imidazolinone ring. The other at RT of 12.9 rain was identified as quinoline-2,3-dicarboxylic anhydride, resulting from detachment of imidazolinone ring and the forming of dicarboxylic anhydride. This finding suggested that the addition of farm litters into soil might be a good management option since it can not only increase soil fertility but also contribute to increase safety of imazaquin application to the following susceptible crops.  相似文献   
60.
Building a community that is resilient to disasters has become one of the main goals of disaster management. Communities that are more disaster resilient often experience less impact from the disaster and reduced recovery periods afterwards. This study develops a methodology for constructing a set of indicators measuring Community Disaster Resilience Index (CDRI) in terms of human, social, economic, environmental, and institutional factors. In this study, the degree of community resilience to natural disasters was measured for 229 local municipalities in Korea, followed by an examination of the relationship between the aggregated CDRI and disaster losses, using an ordinary least squares (OLS) regression method and a geographically weighted regression (GWR) method. Identifying the extent of community resilience to natural disasters would provide emergency managers and decision-makers with strategic directions for improving local communities' resilience to natural disasters while reducing the negative impacts of disasters.  相似文献   
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