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441.
在收集和分析对生态工业发展研究的文献基础上,将影响生态化工产业发展的因素归纳为3大因素:直接因素、间接因素和机制性因素,6个二级指标,分别是自然因素、经济因素、技术因素、产业因素、社会因素、政策法规,同时针对全国第一化工大省山东省不同类型、不同地域的11家化工企业进行了实地调研,并对问卷调研数据进行了基于SPSS软件的克朗巴哈α系数的信度分析以及主成分分析,结果表明问卷具有良好的信度,并按各二级指标中所含因素的重要程度确定了影响生态化工产业发展的12个主要因素,在此基础上提出了化工产业生态化发展的建议,为化工产业生态化建设提供相应的理论支撑。 相似文献
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环保能力建设是环境规划的重要组成部分。物联网作为信息技术的深度拓展应用,在国家和山西省的环境保护“十二五”规划中都提出要推进物联网技术在环保领域的应用,加强环保监管能力建设。本文研究分析了山西省环保监管能力建设现状与需求,围绕环保物联网的三层技术架构和三条业务主线构建了山西省环保物联网建设的总体框架,实现了三个方面的环境管理创新。环保物联网建设对于进一步推动我省环保能力建设向科学化、精细化和智能化转变,实现“十二五”乃至“十三五”环境规划战略目标具有重要意义。 相似文献
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Fossil record of Phanerozoic non-spicular sponges, beside of being important with respect to the lineage evolution per se, could provide valuable references for the investigation of Precambrian ancestral animal fossils. However, although modern phylogenomic studies resolve non-spicular demosponges as the sister group of the remaining spiculate demosponges, the fossil record of the former is extremely sparse or unexplored compared to that of the latter; the Middle Cambrian Vauxiidae Walcott 1920, is the only confirmed fossil taxon of non-spicular demosponges. Here, we describe carbonate materials from Devonian (Upper Givetian to Lower Frasnian) bioherms of northern France and Triassic (Anisian) microbialites of Poland that most likely represent fossil remnants of keratose demosponges. These putative fossils of keratose demosponges are preserved as automicritic clumps. They are morphologically distinguishable from microbial fabrics but similar to other spiculate sponge fossils, except that the skeletal elements consist of fibrous networks instead of assembled spicules. Consistent with the immunological behavior of sponges, these fibrous skeletons often form a rim at the edge of the automicritic aggregate, separating the inner part of the aggregate from foreign objects. To confirm the architecture of these fibrous networks, two fossil specimens and a modern thorectid sponge for comparison were processed for three-dimensional (3-D) reconstruction using serial grinding tomography. The resulting fossil reconstructions are three-dimensionally anastomosing, like modern keratose demosponges, but their irregular and nonhierarchical meshes indicate a likely verongid affinity, although a precise taxonomic conclusion cannot be made based on the skeletal architecture alone. This study is a preliminary effort, but an important start to identify fossil non-spicular demosponges in carbonates and to re-evaluate their fossilization potential. 相似文献
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This paper presents a methodology for quantifying the effectiveness of water-trading under uncertainty, by developing an optimization model based on the interval-parameter two-stage stochastic program (TSP) technique. In the study, the effectiveness of a water-trading program is measured by the water volume that can be released through trading from a statistical point of view. The methodology can also deal with recourse water allocation problems generated by randomness in water availability and, at the same time, tackle uncertainties expressed as intervals in the trading system. The developed methodology was tested with a hypothetical water-trading program in an agricultural system in the Swift Current Creek watershed, Canada. Study results indicate that the methodology can effectively measure the effectiveness of a trading program through estimating the water volume being released through trading in a long-term view. A sensitivity analysis was also conducted to analyze the effects of different trading costs on the trading program. It shows that the trading efforts would become ineffective when the trading costs are too high. The case study also demonstrates that the trading program is more effective in a dry season when total water availability is in shortage. 相似文献