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551.
地下大型商场火灾时期人员疏散计算机模型 总被引:24,自引:2,他引:22
地下商场的火灾危险性决定了地下商场的防火设计应以保护人员的生命安全为首要目标。为此,开发了火灾时期人员疏散计算机模型FEgress,该模型可以计算在建筑物内不同位置处发生火灾时,从火灾发生到人员疏散结束所需的时间,与火灾模拟软件相结合,可以评价火灾时期人员生命的安全性。本文详细阐述了模型的有关概念及计算原理,并简单介绍FEgress的应用。 相似文献
552.
The present article, based on a study of five village ecosystems, assesses the energy efficiency of rain-fed agriculture in
a dry tropical environment and the impact of agricultural activity on the surrounding natural ecosystems. Agronomic yield
is insufficient to meet the food requirement of the human population, hence 11.5%–49.7% of the required amount of food grains
are imported from the market. Energy requirements of five studied agroecosystems are subsidized considerably by the surrounding
forest in the form of fodder and firewood. Natural ecosystems supply about 80%–95% of fodder needs and 81%–100% of fuelwood
needs. The output-input ratio of agriculture indicated that, on average, 4.1 units of energy are expended to obtain one unit
of agronomic energy. Of this, 3.9 units are supplied by the natural ecosystem. In addition, 38% of the extracted firewood
is marketed. The illegal felling and lopping of trees result in ever-increasing concentric circles of forest destruction around
the villages and together with excessive grazing results in savannization. The forests can be conserved by encouraging fuelwood
plantations (0.7 ha/ha cultivated land) and developing village pastures (1.6 ha/ha cultivated land) and reducing the livestock
numbers. Agricultural production in the region can be stabilized by introducing improved dry farming techniques such as intercropping,
planned rainwater management, and adequate use of fertilizers. 相似文献
553.
F.E. Trainer 《Resources Policy》1983,9(1):43-53
Available estimates of potentially recoverable world mineral and fuel resources are examined with a view to determining whether everyone likely to be living on earth next century could be raised to the material living standards people in developed countries now have. It is concluded that this goal is impossible. A number of fundamentally important implications follow, especially regarding the inappropriateness of growth strategies in general, goals for Third World development, and the need for ‘de-development’ of developed countries to much more frugal, self-sufficient and cooperative social systems. 相似文献
554.
生态工业园区建设理论探讨 总被引:4,自引:1,他引:3
资源和环境问题是我国面临的严重的生态安全和环境安全问题 ,也是制约我国经济可持续发展的问题。生态工业是与环境协调发展的环境友好的工业体系。生态工业园是实现生态工业的理想的生态系统 ,通过工业园区内物质流、能量流、信息流和正确设计来模拟自然生态系统 ,形成企业间的共生网络 ,从而解决工业发展与资源和环境保护之间的相互制约的关系。随着我国工业化进程的推进 ,生态工业园区的建设步伐也在加快。笔者对生态工业园区建设的总体思路、建设指标以及建设过程中存在的主要问题等内容进行了理论探讨。以期抛砖引玉 ,促进生态工业园区的理论研究 ,推动生态工业园区在我国的实践。 相似文献
555.
CITYgreen® software has become a commonly used tool to quantify the benefits of urban shade trees. Despite its frequent use, little research has been conducted to validate results of the CITYgreen energy conservation module. The first objective of this study is to perform a familiar application of CITYgreen software to predict the potential energy savings contribution of existing tree canopies in residential neighborhoods during peak cooling summer months. Unlike previous studies utilizing CITYgreen, this study also seeks to assess the software’s performance by comparing model results (i.e., predicted energy savings) with actual savings (i.e., savings derived directly from energy consumption data provided by the electric utility provider). Homeowners in an older neighborhood with established trees were found to use less energy for air-conditioning than homeowners in a recently developed site. Results from the assessment of model performance indicated that CITYgreen more accurately estimated the energy savings in the highly vegetated, older neighborhood. 相似文献
556.
A.N.M. Peeters A.P.C. Faaij W.C. Turkenburg 《International Journal of Greenhouse Gas Control》2007,1(4):396-417
We performed a detailed analysis of the potential future costs and performance of post-combustion CO2 absorption in combination with a natural gas combined cycle (NGCC). After researching state-of-the-art technology, an Excel model was created to analyze possible developments in the performance of energy conversion, CO2 capture, and CO2 compression. The input variables for the three time frames we used were based on literature data, product information, expert opinions, and our own analysis. Using a natural gas price of 4.7 €/GJ, we calculated a potential decrease in the costs of electricity from 5.6 €ct/kWh in the short term to 4.8 €ct/kWh in the medium term and 4.5 €ct/kWh in the long term. The efficiency penalty is calculated to decline from 7.9%-points LHV in the short term to 4.9%-points and 3.7%-points in the medium and long terms, respectively. In combination with NGCC improvements, this may cause an improvement in the net efficiency, including CO2 capture, from 49% in the short term to 55% and 58% in the medium and long terms, respectively. The total capital costs including capital costs of the NGCC ware calculated to decline from 880 in the short term to 750 and 690 €/kW in the medium and long terms, respectively, with a decline in the incremental capital costs due to capture from 350 in the short term to 270 and 240 €/kW in the medium and long terms, respectively. Finally, the avoidance costs may decline from 45 €/tCO2 in the short term to 33 €/tCO2 in the medium term and 28 €/tCO2 in the long term. 相似文献
557.
Burger J Gochfeld M Kosson DS Powers CW Friedlander B Eichelberger J Barnes D Duffy LK Jewett SC Volz CD 《Environmental management》2005,35(5):557-568
With the ending of the Cold War, the US Department of Energy is responsible for the remediation of radioactive waste and disposal of land no longer needed for nuclear material production or related national security missions. The task of characterizing the hazards and risks from radionuclides is necessary for assuring the protection of health of humans and the environment. This is a particularly daunting task for those sites that had underground testing of nuclear weapons, where the radioactive contamination is currently inaccessible. Herein we report on the development of a Science Plan to characterize the physical and biological marine environment around Amchitka Island in the Aleutian chain of Alaska, where three underground nuclear tests were conducted (1965–1971). Information on the ecology, geology, and current radionuclide levels in biota, water, and sediment is necessary for evaluating possible current contamination and to serve as a baseline for developing a plan to ensure human and ecosystem health in perpetuity. Other information required includes identifying the location of the salt water/fresh water interface where migration to the ocean might occur in the future and determining groundwater recharge balances, as well as assessing other physical/geological features of Amchitka near the test sites. The Science Plan is needed to address the confusing and conflicting information available to the public about radionuclide risks from underground nuclear blasts in the late 1960s and early 1970s, as well as the potential for volcanic or seismic activity to disrupt shot cavities or accelerate migration of radionuclides into the sea. Developing a Science Plan involved agreement among regulators and other stakeholders, assignment of the task to the Consortium for Risk Evaluation with Stakeholder Participation, and development of a consensus Science Plan that dealt with contentious scientific issues. Involvement of the regulators (State of Alaska), resource trustees (U S Fish and Wildlife Service), representatives of the Aleut and Pribilof Island communities, and other stakeholders was essential for plan development and approval, although this created tensions because of the different objectives of each group. The complicated process of developing a Science Plan involved iterations and interactions with multiple agencies and organizations, scientists in several disciplines, regulators, and the participation of Aleut people in their home communities, as well as the general public. The importance of including all parties in all phases of the development of the Science Plan was critical to its acceptance by a broad range of regulators, agencies, resource trustees, Aleutian/Pribilof communities, and other stakeholders. 相似文献
558.
Indicators for sustainable energy development: An initiative by the International Atomic Energy Agency 总被引:1,自引:0,他引:1
I. A. Vera L. M. Langlois H. H. Rogner A. I. Jalal F. L. Toth 《Natural resources forum》2005,29(4):274-283
Since 1999, the International Atomic Energy Agency (IAEA) has been leading a multinational, multi‐agency effort to develop a set of energy indicators useful for measuring progress on sustainable development at the national level. This effort has included the identification of major relevant energy indicators, the development of a framework for implementation and the testing of the applicability of this tool in a number of countries. To achieve these goals, the IAEA has worked closely with other international organizations, leaders in energy and environmental statistics and analysis including the United Nations Department of Economic and Social Affairs (DESA), the International Energy Agency (IEA), Eurostat and the European Environment Agency (EEA). Also, the IAEA completed a three‐year coordinated research project for the implementation and testing of the original set of indicators in seven countries — Brazil, Cuba, Lithuania, Mexico, the Russian Federation, the Slovak Republic and Thailand. This article provides an overview of the IAEA programme on Indicators for Sustainable Energy Development (ISED) and highlights its experiences and accomplishments. 相似文献
559.
This article examines energy priorities for Thailand from the economic, social and environmental perspectives of sustainable development. The article uses a set of indicators devised by the International Atomic Energy Agency in partnership with other international agencies and research institutes in seven countries. Thailand's energy efficiency in the 1980s and 1990s are analysed using energy intensity indicators, and possible impacts on sustainable energy development are highlighted. The early 1990s in particular was an important period for Thailand, as the country was at the height of its economic growth, and a number of energy efficiency and conservation programmes were launched. Energy intensity indicators show continuing and faster growth in energy consumption relative to economic activity. The financial crisis in the late 1990s did halt growth in energy consumption, with positive consequences on environmental emissions, but only temporarily as Thailand's economy quickly started to recover in 2000. Notwithstanding the financial crisis, the other indicators show significant progress in economic and social dimensions. 相似文献
560.
The European Environment Agency (EEA) is the European Union body dedicated to providing sound, independent information on the environment. It is a major information source for those involved in developing, adopting, implementing and evaluating environmental policy in Europe, and also for the general public. In line with its mandate, the EEA has developed — focused around a set of policy relevant questions — a set of indicators to assess progress in Europe in integrating environmental considerations into the energy sector. Each question is answered through one or more indicators describing the development of the sector in Europe, implications for the environment and links to policy actions. The indicators cover not only the current situation, but also trends and prospects and, most importantly, point to the conditions for change that are needed for progress towards a more sustainable energy policy that benefits the environment. The results of the most recent assessment are presented in this article and show that in many areas of environmental integration there have been some successes, but overall progress to date has been insufficient. Substantial additional action will therefore be required in the future if the European Union is going to move towards a more environmentally sustainable energy system. 相似文献