首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   717篇
  免费   3篇
  国内免费   8篇
安全科学   19篇
废物处理   37篇
环保管理   78篇
综合类   128篇
基础理论   101篇
污染及防治   258篇
评价与监测   62篇
社会与环境   42篇
灾害及防治   3篇
  2023年   9篇
  2022年   22篇
  2021年   17篇
  2020年   13篇
  2019年   7篇
  2018年   19篇
  2017年   24篇
  2016年   30篇
  2015年   24篇
  2014年   44篇
  2013年   77篇
  2012年   51篇
  2011年   57篇
  2010年   31篇
  2009年   34篇
  2008年   53篇
  2007年   37篇
  2006年   35篇
  2005年   37篇
  2004年   21篇
  2003年   23篇
  2002年   13篇
  2001年   8篇
  2000年   3篇
  1999年   2篇
  1998年   4篇
  1997年   3篇
  1996年   4篇
  1995年   2篇
  1994年   6篇
  1993年   2篇
  1992年   2篇
  1991年   1篇
  1990年   2篇
  1989年   1篇
  1988年   4篇
  1986年   2篇
  1982年   1篇
  1978年   1篇
  1973年   1篇
  1954年   1篇
排序方式: 共有728条查询结果,搜索用时 453 毫秒
241.
Food and Environmental Virology - Kinetics of hepatitis A virus (HAV) accumulation and depuration from mussels (Mytilus galloprovincialis) was studied in an experimental depuration system....  相似文献   
242.
Food and Environmental Virology - The experience of COVID19 pandemic has demonstrated the real concern of biological agents dispersed in the air and surfaces environments. Therefore, the need of a...  相似文献   
243.
This paper examines human factors associated with piloting a totally enclosed motor propelled survival craft (TEMPSC or lifeboat) in ice. The first section of the paper describes the use of a usability assessment scale to evaluate the coxswain’s (TEMPSC captain) control panel. The second portion examines environmental conditions (habitability) inside the lifeboat during evacuation. All testing was completed in conditions that were consistent with those that might be experienced by ship or offshore oil and gas crewmembers in the event of abandonment due to an onboard emergency. Results indicated that the lifeboat test configuration presented considerable challenges to usability/functionality as well as habitability. These findings suggest that further research should be conducted to evaluate the safety of all existing lifeboat designs. Finally, it is recommended that the international maritime organization (IMO) and safety of life at sea (SOLAS) Convention should mandate user-centered design evaluations for future lifeboat manufacturing.  相似文献   
244.
The environmental problem caused by the effluents from the four main agrifood industries in Extremadura (W Spain) is evaluated in the present work. In particular, attention is paid to the management of wastes from slaughterhouse operations. Pollution is quantified in terms of equivalent population and biological oxygen demand, for which very high values are reported.Efforts are also focused on the search of viable technical solutions for the treatment of those residues and their energetic valuation. In this sense, anaerobic digestion techniques are proposed, not only because they lead to a drastic decrease in their pollution potential, but also because significant volumes of biogas are obtained. This biogas might be used to produce electricity to be transferred to the electrical network. This way, anaerobic digestion plants would allow depreciation within a relatively short period.In particular, an analysis of the economics of a plant for the codigestion of solid and liquid effluents from meat industry is carried out, and a payback time between 7 and 8 years was achieved.  相似文献   
245.
Numerical and experimental analysis of wind erosion on a sinusoidal pile   总被引:1,自引:0,他引:1  
Erosion is a common phenomenon in nature, and it may cause a wide range of problems such as air pollution, and destruction of agricultural land, shelters and stockpiles. The present work deals with stockpiles, which have their profiles described by a sinus function or by similar trigonometric functions. Analysis of the erosion by air flow over these piles will provide for further understanding of the erosion underlying mechanisms and, moreover, how to control them and eventually to prevent them. To this purpose, different experimental tests are conducted for a pile with a sinuous profile, and particular attention is given to the time development of the profile due to the erosion process; the effect of the air velocity is also studied by selecting different velocities. In addition, the flow over several deformed piles is numerically predicted using the CFX software; the results clearly show the erosion process is strongly dependent upon time, velocity field and surface disturbances. A correlation between the erosion rate and the velocity is proposed.  相似文献   
246.
Trace transition metals (Fe3?+?, Mn, Cu, Cd, Co, Zn, Ni) in environmental samples were analyzed by chelation ion chromatography using a mixed bed ion-exchange column with pyridine-2,6-dicarboxylic acid (PDCA) and oxalic acid as eluent and large volume direct injection (1,000 ??l). The two eluents, PDCA and oxalic acid, were tested, and repeatability and detection limits were compared. The total analysis time was ~15 min. The separation with PDCA was more successful than that obtained with acid oxalic. It was observed that utilizing PDCA resulted in lower detection limits, higher repeatability, and a quantitative detection of Cd and Mn, which coelute as a single peak when using the oxalic acid. At last, the PDCA calibration graphs resulted linear (r 2?>?0.999) in the range 0.4?C1,000 ??g/L. The procedure was applied to the analysis of metals in soils and in water samples. The results obtained from the analysis of natural waters have demonstrated that the method is simple and efficient, therefore, can be used for the determination of metals in natural waters using a continuous and automatic monitoring system.  相似文献   
247.
Human factors deal with issues related to humans, their behavior and the physical aspect of the environment in which they work. A control room is a complex system where operators perform plant operation using control systems and carry out monitoring and administrative responsibilities. For safe operation of industrial installation, the performance of the control room crew plays an important role. In this respect, a well designed control room is crucial for safe and efficient operation. The aim of this paper is to propose a methodological framework applied to nuclear control room evaluation, through participatory ergonomics, using operator activity analysis and human factors questionnaire as aid tools. We describe a case study in which the methodology framework was used in the evaluation process of a nuclear control room. The information gathered made possible a series of recommendation for the adequacy of the control room design, assisting in the safety assessment of the nuclear plant operation and justifying the alarm panel modernization.  相似文献   
248.
The benefits and drawbacks consequent to the widespread use of chemicals are inextricably interwoven. According to recent estimates, more than 8 million substances are presently known, 70,000 of which are in common use as industrial compounds, pesticides, Pharmaceuticals, food additives, cosmetics and the like. It is estimated that substances used as such will increase annually by 1000 in number. The deleterious consequences deriving from their exploitation pose tremendous challenges to the scientific community for the protection of human health and the environment. Therefore it is of utmost priority to appropriately select valid information generated in this investigation area and to convey it correctly to users. Here, the adoption of the principles of good laboratory practice in experimental activities is essential, as well as the creation of global networks for data exchange on the safe use of chemicals. The structure and goals of the International Register of Potentially Toxic Chemicals (IRPTC, the database of the United Nations Environment Programme) are detailed to give an example of such an undertaking. Seventeen fields are covered,i.e. identifiers, properties and classification, production/trade, production processes, use, pathways into the environment, concentrations, environmental fate tests, environmental fate, chemobiokinetics, mammalian toxicity, special toxicity studies, effects on organisms in the environment, sampling/preparation/analysis, spills, treatment of poisoning, waste management and recommendations/legal mechanisms.  相似文献   
249.
250.
Summary The depletion of the world's natural resources continues relentlessly. Plants and animals alike are being trapped into ever more numerous shrinking pockets, as man advances to incorporate virgin estates into areas of productivity. The immediate consequence of such an all-out attack in the tropical areas of under-developed countries is the destruction of habitats and the likely break-up of food webs. The attendant disastrous effects on the reproduction of species, hence, puts natural selection at a premium. This scenario has distinctly impressed different people in different places. This suggests diverse sensitivity even for causes voiced in public as matters of sheer truism. The study concentrates on the examination of the dialectic nature/nurture controversy to see whether this may account for the state of disharmony recorded between man and nature. Conversion of nature is traditionally considered a realm of the scientific establishment. The study tries to suggest that the humanities cannot be left out in any debate on the interpretation of the environment. The synthesis reveals a blatant refusal of social determinism as causal agent and, with some reservation, projects biological determinism into sharp focus for pertinent consideration. The cautious reconciliation with parts of sociobiological tenets was regarded as inevitable once grasped that will, knowledge, and sensitivity, were interpreted as the foundation of the main teleological argument.Dr Antonio Allem is trained as a plant taxonomist. His research has focused on the collection of plant genetic resources germ plasm. He has recently written (with J.F.M. Valls) a book entitledRecursos Forrageiros Nativos do Pantanal Mato-Grossense, published by the Departamento de Difusão de Tecnologia, EMBRAPA, Brasilia. He has an interest in the taxonomy of cultivated plants and has recently solved the origin of the cassava plant (Manihot esculenta, Euphorbiaceae). Dr Allem is a member of staff of thein situ conservation unit at Centro Nacional de Recursos Genéticos e Biotecnologia da Empresa Brasileira de Pesquisa Agropecuária.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号