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排序方式: 共有648条查询结果,搜索用时 15 毫秒
641.
讨论现有标准对铁路两侧声环境功能区划分的适用性,概括与铁路两侧声环境功能区划分相关的研究成果,提出尽快制定铁路两侧声环境功能区划分标准的建议.  相似文献   
642.
价值工程在环境监测仪器设备建设中的应用   总被引:1,自引:0,他引:1  
在环境监测仪器设备建设中应用价值工程原理和方法,对仪器设备配置方案进行评估.结果表明,价值工程有利于合理地配置各类仪器设备,选择与其功能相适应的成本价位,充分发挥仪器设备建设资金的使用效益,提高环境监测总体能力.  相似文献   
643.
白洋淀水生态综合调控决策支持系统设计   总被引:1,自引:0,他引:1  
在充分挖掘白洋淀污染源控制、富营养化与沼泽化治理、长效生态节水及流域综合管理协调相关研究成果的基础上,以流域水生态系统健康和生态安全保障为目标,设计了集水生态系统健康诊断、水生态安全预警与应急、水量调控、污染物控制、淀区净化、综合调控、知识库子系统于一体的白洋淀水生态综合调控决策支持系统,为白洋淀流域的水生态安全保障提...  相似文献   
644.
Hydroelectricity has been rated to have a large water footprint (WF) on global average. We assessed the WF of hydroelectricity by three different methods using New Zealand as a case study. The first (WF-1) and second (WF-2) methods only consider the consumptive water use of the hydroelectricity generation system, while our third method (WF-3) accounts for the net water balance. Irrespective of the method, the WF of New Zealand’s hydroelectricity was found much smaller than the commonly cited international value of 22 m3 GJ−1. Depending on the method, the national WF ranged from 1.55 m3 GJ−1 (WF-3) to 6.05 m3 GJ−1 (WF-1). The WF- 3 considers the net water balance including rainfall, which is the key driver for replenishing water resources. It provides meaningful information that helps our understanding of the differences of the WF in locations, which are diverse in terms of water resource availability. We highlight the effects of local climatic differences and the structural specifics of a hydroelectricity scheme on the WF. The large variation in the WF of hydropower across New Zealand illustrates the inappropriateness of using global average values. Local values, calculated using our hydrologically rational method, must be used.  相似文献   
645.
The aim of this study is to contribute to the analysis of the environmental impacts deriving from common aspects of the service sector activity and to identify auxiliary actions and hot spots in order to improve the environmental performance of offices used for educational purposes. In that aspect, a screening life cycle assessment (LCA) for a university office-workstation of Democritus University of Thrace, Greece, was performed with the application of the SimaPro LCA software, and the Impact 2002+ method with fifteen impact categories for the interpretation of results. Findings from this research indicated that energy consumption for the powering electronic appliances was the key factor affecting most of the environmental impact categories examined. The impact categories most seriously affected by the office life cycle were the emissions of respiratory inorganics (39%), global warming (31%) and non-renewable energy use (27%). The saving of the energy consumed due to standby mode could lead to a reduction of 2.4% of the total energy consumption in the office in a yearly basis with proportional positive influence in all the respective impact categories. Additionally, utilization of solar energy through photovoltaic panels could lead to a reduction close to 90% for a number of impact categories. Therefore, actions and strategies for improving the environmental performance of academic offices should focus on the reduction of energy consumption.  相似文献   
646.
Land classification used to select abandoned hazardous waste study sites   总被引:2,自引:0,他引:2  
The biological effects of hazardous substances in the environment are influenced by climate, physiography, and biota. These factors interact to determine the transport and fate of chemicals, but are difficult to model accurately except for small areas with a large data base. The requirement for a large data base may be reduced locally if the regional influences of these factors were predetermined from existing data. Knowledge of the regional factors would also relax the restriction to considering only small areas. This paper advocates consideration of regional characteristics of the environment in the early stages of waste management strategy development. It presents as an example a procedure for selecting study sites from candidate-abandoned hazardous waste dumpsites in the southeastern United States. It uses small-scale maps of low resolution from the National Atlas to delineate the boundaries and to determine the environmental characteristics that prevail over units of land within the region. A computer map-overlay and graphic approach is used to facilitate the grouping of land types. Abandoned hazardous waste dumpsites found within land types that best represent the region are surveyed for selecting a study site. It is expected that environmental impact data obtained from a representative site would be useful for predicting impact potentials in similar remotely located areas within the same general region.  相似文献   
647.
综述了近年来我国大气、水、土壤环境和生态系统中多环芳烃(PAHs)污染状况研究进展,指出化石燃料及其衍生物的燃烧产物是PAHs的主要来源,虽然我国大部分地区生态环境中PAHs风险较低,但仍须关注其潜在的健康风险,提出多学科交叉研究典型PAHs在生态系统中的环境行为及原位修复技术等未来研究方向。  相似文献   
648.
Packaging waste collection systems are responsible to collect, within a geographic area, three types of packaging materials (paper, glass and plastic/metal) that are disposed by the final consumer into special bins. Those systems are often characterized by having a network with multiple depots that act as transfer and sorting stations, and where the vehicle fleet is based. However, each depot is often managed independently and not as a part of a unique system. In this work, four current tactical/operational practices that contribute to the independent management of each depot are analysed. The change of such practices is investigated and their impact assessed on the total collection cost. A solution methodology based on mathematical formulations is developed to plan service areas, vehicle routes and vehicle schedules taking into account new alternative solutions in managing the system as a whole. Such methodology is applied to a real case study of a company responsible for the collection of the packaging waste in 7 municipalities in mainland Portugal. New service areas, collection routes and vehicle schedules are defined and significant savings are obtained in terms of the total distance travelled as well as in terms of the number of required vehicles, resulting in a decreasing of the total system cost.  相似文献   
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