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571.
在对食物生产系统进行环境相关的系统分析中,消费者阶段(家庭运输、烹制、储存和损耗)是整个食物生命周期中对环境产生影响的一个重要因素.然而,家庭是食物链中调查最少的部分.对家庭信息的收集有很多困难,因为家庭数量庞大,同时与食物相关的活动通常会与其它家务劳动活动混合在一起.环境系统分析和消费者研究两领域研究人员相互合作,通过用问卷、日记和采访面谈的方式调查瑞典的家庭,收集了关于家庭食物运输和损耗的数据.每户每周的平均运输距离是28~63km不等,而这主要依靠怎样分配和其它差事相搭配的运输任务.调制食品时的损耗变化范围是0~34%,而不同类型的食品会有所不同.储存的损耗率为0~164%(因为有更多的食物被扔掉,如对食橱的清理,而不是消费).在调制和储存两阶段中奶制品因损耗少而得分最高.  相似文献   
572.
ABSTRACT .Inherent in every decision process is a certain amount of uncertainty, which is reduced with information. Perfect knowledge yields no uncertainty for a process, but perfect knowledge for hydrologic and water resource systems would require a highly excessive investment. Therefore, it is the aim of this paper to delineate a procedure that places a value on this uncertainty so that it may be compared to a cost of further investment, which would provide a basis for deciding the time at which the value of additional data does not exceed the cost of that data. A decision theory approach is employed on a hydrologic problem to formalize the steps in making a decision. Examples are given.  相似文献   
573.
574.
In Brazil, artisanal and small-scale gold mining (ASGM) produces in the range of 6 tonnes of gold (Au) per annum, and employs approximately 200,000 people. Most of this mining activity is in the Amazon region, where miners have been extracting gold for more than 40 years. In the Tapajos River Basin, assessments indicate that around 99% of miners operate without the environmental and mining permits required by law. This is a result of a combination of unrealistic or lack of proper policies and regulations, lack of political will, lack of infra-structure to enforce the existing regulations and lack of incentives to miners to comply with legal requirements.In this article, we analyze a group of 20 laws, decrees and resolutions in Brazil, focusing on how idiosyncrasies in these regulations reveal gaps between policy and reality in ASGM areas. Artisanal miners operate in vast and remote areas and the government lacks the resources (personnel, vehicles, information and materials) to enforce the laws. Our analysis emphasizes the need for creating new government commitments and identifying priority areas where government agents can focus their efforts.There is no single solution for the environmental, health, technical and socio-economic problems associated with ASGM. However, a realistic approach should consider improving the level of education of miners, creating government programs to provide technical assistance in the field, simplifying administrative procedures and ensuring adequate measures for enforcement.  相似文献   
575.
This paper describes techniques which provide for both qualitative and quantitative identification of major components in a process stream. The techniques and instrumentation have been deliberately chosen so as to be within the technical and financial reach of all but the smallecompany laboratory. The sample preparation steps consist of an initial series of extractions which isolate compounds into organic acid, base, and neutral compounds and a totally water soluble phase. Each fraction is then concentrated and subjected to thin-layer chromatography, gas chromatography, infrared spectroscopy or ultraviolet spectroscopy as appropriate. Results are given for laboratory samples, one a mixture of aniline, phenol, benzoic acid, m-nitrobenzaldehyde, 1-butanol, 2-hexanone, nonane, and cyclohexane, and the other a mixture of benzene, ethylbenzene, and styrene. Also, a qualitative analysis of a petroleum refinery desalter water is presented.  相似文献   
576.
Summary This overview paper examines past Australian conservation controversies and experiences to identify prospective means of ameliorating environmental conflict in the future. Since all community disputes should be resolved by means of political and administrative actions, emphasis is placed on federalism and intergovernmental relations, and measures are suggested which might improve environmental policy and practices in the future.Dr Bruce W. Davis is currently Head of the Department of Political Science, Dean of the Faculty of Arts, and member of the Council of the University of Tasmania. He possesses qualifications and professional experience in engineering, economics and administration. He has numerous publications within the fields of public sector planning and natural resources management, and acts in an advisory and consulting capacity to State and Federal agencies involved in national parks administration, heritage conservation and land-use planning.In addition to University commitments, Dr Davis holds the following appointments: Commissioner, Australian Heritage Commission; Member, Australian National Commission for UNESCO, Man and Biosphere Program; Trustee, World Wildlife Fund Australia; Councillor, Australian Conservation Foundation; and Consultant to IUCN, Gland, Switzerland.  相似文献   
577.
The SIRO‐Plan method was evolved in the CSIRO Division of Water and Land Resources, Canberra, in response to what was seen as an absence in literature of a procedural theory calling for the use of both systematically acquired resource inventory data and expressions of community demands. The paper records a selection of insights accumulated and lessons learned during six years of effort to improve the usefulness of the method.  相似文献   
578.
ABSTRACT: The U.S. Army Corps of Engineers has broad, nationwide water resources planning and management responsibilities. In response to the needs of Corps professionals, the Hydrologic Engineering Center (HEC) has developed and supports a family of computer programs designed to aid them in their work. These programs include catchment, channel, alluvial, and statistical process models, system operation models, plan evaluation models, and data management programs. These models individually and collectively have been used throughout the Corps in a wide range of water resources planning studies.  相似文献   
579.
ABSTRACT The role of water resources in the urban economic and social environment, particularly in the inner city, has never been established to the degree necessary for making informed decisions on investments in urban waterway and shoreline improvements. The basic tools for measuring psychological and social impacts of waterway and shoreline developments in the inner city have not been fully developed and utilized to date. However, through a detailed analysis of the water resources in the urban core area of Cleveland, it appears that deliberate development of water-based recreation and other environmental resources can lead to improvement in some of the social problems of the inner city. In recreation analysis, there is currently a great gap between methodologies that are conceptually sound and those that have been applied by urban and water-resources planning agencies. New tools and methodologies can only be used successfully when public agencies are given the institutional and policy means for using them equitably in light of social needs. Present urban-water planning practices have been found to be biased against the inner city, often unintentionally.  相似文献   
580.
ABSTRACT Coal ash effluent effects including particulates, acidic pH excursions, elemental concentrations and bioconcentration in selected organisms have been studied as changes in water quality and densities of benthic macroinvertebrate and mosquitofish (Gambusia affinis) populations in a swamp drainage system over an eight-year period. Three changes in the ash basin settling system were made between mid- 1973 and January 1982. Initial density of the aquatic biota was altered severely by heavy ash siltation, followed by acidic pH excursions and perhaps overall by elemental concentrations and bioaccumulation. Heavy ash siltation, followed by acidic Ph excursions (mean of 5.5, extreme of 3.5) after the addition of fly ash to the original settling basin system, had the most profound effect on biota. Dipterans (chironomids) and some odonates (Plathemis lydia and Libellula spp.) were resistant to heavy ash siltation, while mosquitofish, which showed no discernible responses to ash siltation, were absent at acidic pH, along with the few previously surviving invertebrate populations. Elemental concentrations of arsenic, cadmium, chromium, copper, selenium, and zinc did not appear to limit aquatic flora and fauna on a short-term, acute basis. Long, chronic elemental exposures may have been instrumental in retarding the recovery of all forms of aquatic life in the receiving system. Elemental concentrations (except for arsenic and selenium) in the receiving system were generally one to two orders of magnitude higher than the Water Quality Criteria set by the U.S. Environmental Protection Agency (1980) for protection of aquatic life for the minimum and 24-hour mean values. From collective elemental exposures in the receiving system, bioconcentration factors in macrophytes, invertebrates and fish were generally lower than those reported in the literature for laboratory, single elemental concentrations. By 1978, when the new settling basin systems were operating effectively, invertebrate populations were largely recovered, and mosquitofish populations recovered within one year afterward.  相似文献   
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