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851.
Minghui Xie Li Li Qi Qiao Qihong Sun Tichang Sun 《Journal of Cleaner Production》2011,19(17-18):2100-2106
A Life Cycle Assessment (LCA) approach was used to compare the environmental impacts in the life cycle of two milk packaging systems, PA-PE-Al laminate—a laminated foil made from paper, polyethylene and aluminum foil—and polyethylene. The data for the mass, energy fluxes and environmental emissions were obtained from published literature and from site investigations, for the two systems being analyzed for environmental impacts. The application of LCA using Eco-Indicator 99 has made the comparison of the environmental impacts of the two milk packages possible. The results of this LCA study are discussed and the results reveal that the composite packaging has a slightly higher environmental impact than the plastic one. In addition, the environmental impact of raw material extraction is the highest in all of the life cycle stages except for disposal. The environmental impact of composite packaging mainly comes from the fossil fuels, land use and respiratory inorganics categories, while the plastic packaging mainly comes from the fossil fuels category. However, the composite packaging has a greater environmental impact because it has not been well recycled and reused. This environmental impact could be decreased by developing the technology to separate out polyethylene and aluminum from the packaging. 相似文献
852.
化工事故应急救援仿真演练系统的实施探讨 总被引:4,自引:1,他引:3
阐述了化工事故应急救援仿真的必要性及其国内外研究进展;提出整个系统的框架并设计系统开发过程的模型;分析了基于高层体系结构(HIA)的仿真系统的开发要点,给出参考开发工具,从而为整个系统开发提供思路. 相似文献
853.
核电厂核事故应急疏散研究 总被引:1,自引:1,他引:0
根据我国法规、标准与美国核管委对核电厂核事故应急疏散的要求,考虑我国核电厂特殊的厂址条件与社会环境,分析核事故应急疏散的可行性。通过应急疏散行为研究、厂区的交通需求估计和路网分析,对不同情境,考虑核事故应急疏散的特殊问题,分别采用人工容量分析与宏观仿真模拟得到应急疏散时间。针对某核电厂,给出核事故应急疏散分析的一般步骤、方法与计算结果。对宏观仿真模型的主要参数进行灵敏度分析,找出影响应急疏散时间的主要因素,提出缩短应急疏散时间的针对性措施。 相似文献
854.
本文论述了贵州省的野生生物资源概况,揭示了资源开发利用存在的问题,并对资源的开发利用与保护提出了建议。 相似文献
855.
856.
Land-cover change in upper Barataria Basin estuary,Louisiana, 1972-1992: increases in Wetland area 总被引:1,自引:0,他引:1
The Barataria Basin, Louisiana, USA, is an extensive wetland and coastal estuary system of great economic and intrinsic value.
Although high rates of wetland loss along the coastal margin of the Barataria Basin have been well documented, little information
exists on whether freshwater wetlands in the upper basin have changed. Our objectives were to quantify land-cover change in
the upper basin over 20 years from 1972–1992 and to determine land-cover transition rates among land-cover types. Using 80-m
resolution Landsat MSS data from the North American Landscape Characterization (NALC) data archive, we classified images from
three time steps (1972, 1985, 1992) into six land-cover types: agriculture, urban, bottomland hardwood forest, swamp forest,
freshwater marsh, and open water. Significant changes in land cover occurred within the upper Barataria Basin over the study
period. Urban land increased from 8% to 17% of the total upper basin area, primarily due to conversions from agricultural
land, and to a lesser degree, bottomland forest. Swamp forest increased from 30% to 41%, associated with conversions from
bottomland hardwood forest and freshwater marsh. Overall, bottomland forest decreased 38% and total wetland area increased
21%. Within the upper Barataria, increases in total wetland area may be due to land subsidence. Based on our results, if present
trends in the reduction of bottomland forest land cover were to continue, the upper Barataria Basin may have no bottomland
hardwood forests left by the year 2025, as it is subjected to multiple stressors both in the higher elevations (from urbanization)
and lower elevations (most likely from land subsidence). These results suggest that changes in the upper freshwater portions
of coastal estuaries can be large and quite different from patterns observed in the more saline coastal margins. 相似文献
857.
根据齐鲁石化公司局域电网谐波源的测试结果,并结合公司新区电网的特点,确定了谐波源治理方案,并在工程中实施。测试结果表明,治理效果达到了设计要求,电网的电压畸变率被控制在国家标准允许的范围之内。 相似文献
858.
859.
860.
2001年10-12月国内环境事件数据 总被引:4,自引:18,他引:4
简要统计了201年10-12月国内发生的各种污染事件和自然灾害.包括大气污染、水体污染、放射性物质污染以及地震、病虫害、山体滑坡、泥石流等灾害. 相似文献