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221.
物联网技术作为一项新兴的网络技术,在各领域都得到了广泛的应用,它的发展必将改变人们的生活方式,并推动社会的巨大变革。重点介绍了物联网技术在垃圾收运监管体系中的应用,为环卫信息化建设和环卫主管部门管理方式的改变提供借鉴。 相似文献
222.
采用自主研制的电磁辐射采集系统,深入研究受载复合煤岩变形破裂电磁辐射中频信号特性。在前置部分的天线和电缆之间加入巴伦,把从振子流过电缆屏蔽层外皮的高频电流截断,减小信号的传输损耗,提取电磁辐射信号,分析其在加载各个阶段的分布规律和特征。结果表明:复合煤岩受载破裂释放的电磁辐射能量主要集中于500 kHz~1 MHz中频段,电磁辐射信号整体与应力相关性较高,相关系数大于0.8。 相似文献
223.
Caroline Fukushima Rick West Thomas Pape Lyubomir Penev Leif Schulman Pedro Cardoso 《Conservation biology》2021,35(1):5-11
Illegal transfer of wildlife has 2 main purposes: trade and scientific research. Trade is the most common, whereas scientific research is much less common and unprofitable, yet still important. Biopiracy in science is often neglected despite that many researchers encounter it during their careers. The use of illegally acquired specimens is detected in different research fields, from scientists bioprospecting for new pharmacological substances, to taxonomists working on natural history collections, to researchers working in zoos, aquariums, and botanical gardens. The practice can be due to a lack of knowledge about the permit requirements in different countries or, probably most often, to the generally high level of bureaucracy associated with rule compliance. Significant regulatory filters to avoid biopiracy can be provided by different stakeholders. Natural history collection hosts should adopt strict codes of conduct; editors of scientific publications should require authors to declare that all studied specimens were acquired legally and to cite museum catalog numbers as guarantee of best practices. Scientific societies should actively encourage publication in peer-reviewed journals of work in which specimens collected from the wild were used. The International Commission on Zoological Nomenclature could require newly designated types based on recently collected specimens to be accompanied by statements of deposition in recognized scientific or educational institutions. We also propose the creation of an online platform that gathers information about environmental regulations and permits required for scientific activities in different countries and respective responsible governmental agencies and the simplification of the bureaucracy related to regulating scientific activities. This would make regulations more agile and easier to comply with. The global biodiversity crisis means data need to be collected ever faster, but biopiracy is not the answer and undermines the credibility of science and researchers. It is critical to find a modus vivendi that promotes compliance with regulations and scientific progress. 相似文献
224.
Bakir HA 《Journal of environmental management》2001,61(4):319-328
Accelerated expansion of wastewater services to small communities in the Middle East and North Africa (MENA) is essential in order to address serious concerns over water scarcity and pollution in addition to meeting the demand for convenience and protecting public health. Centralized and conventional wastewater systems are currently the preferred choice of planners and decision-makers in MENA. Water and funding are not available to provide these centralized conventional services to small communities. This paper presents an integrated approach to sustainable wastewater management for small communities in MENA under the severe water resources crisis. The approach calls for a paradigm shift from centralized conventional wastewater systems to decentralized wastewater systems. Management of wastewater in MENA should start at home. Wastewater generation should be reduced through a combination of domestic water conservation measures. On-site systems must be improved and monitored to control pollution and to recover water for non-potable water uses. Should the circumstances not allow the use of on-site systems, wastewater should be transported and managed through a community system applying the principles of decentralized wastewater management and using the settled sewers for wastewater transportation where appropriate. This approach will facilitate the accelerated and sustainable extension of environmentally responsible wastewater services to MENA's small communities. It offers great potential for cost reduction, accommodates the necessary domestic water conservation efforts, reduces freshwater inputs in wastewater transportation thus eliminating unnecessary demand on freshwater, reduces associated environmental risks and increases wastewater reuse opportunities. 相似文献
225.
E. B. Preud'homme H. G. Stefan 《Journal of the American Water Resources Association》1992,28(6):1077-1082
ABSTRACT: Records of hourly water temperatures for two streams in the Upper Mississippi River basin were used to find the error between instantaneous measurements of stream water temperatures and true daily averages. The instantaneous summer water temperature measurements were assumed to be collected during daylight hours, and measurement times were selected randomly. The absolute error at the 95 percent confidence level of randomly collected stream water temperatures was less than 0.9°C for a 1 to 5m deep large river, but as large as 3.6°C for a 0.3 to lm deep small stream. Temperature readings of morning samples were usually below daily average values, and afternoon readings were usually above. Daily mean water temperatures were obtained with less than 0.23°C standard deviation from true daily averages if the daily maximum and minimum water temperatures were averaged. Sample results were obtained for the open water (summer) season only, since diurnal water temperature fluctuations in ice covered streams are usually negligible. 相似文献
226.
Jean E. Weber Chester C. Kisiel Lucien Ducksteiri 《Journal of the American Water Resources Association》1973,9(6):1075-1088
ABSTRACT: Many difficulties exist in the matching of models with data. This paper identifies elements of this problem and discusses considerations involved in model evaluation. The well known multivariate linear regression model is used to illustrate the distinctions between accuracy and precision and between estimation and prediction (because the model is commonly misused.) No amount of additional data will improve the accuracy of a poor model. A high R2, while indicative of a good matching between the observed data and model estimates, is a poor criterion for judging adequacy of the model to make good predictions of future events. Model evaluation also includes the problem of introducing secondary data and proxy variables into a model. Secondary data frequently enter, for example, the mass, energy and water budget equations because of difficulties in measuring the primary variables. Proxy variables arise because of a desire to collapse a vector of incomparable values, say, of water quality into a single number. Review of the above issues indicates that model evaluation is a multi-criterion problem, often imbedded in a larger framework where models are intended to meet multiple objectives. The mismatch of models and data has increasing legal and social consequences. 相似文献
227.
Il-Chung Kim 《Journal of Material Cycles and Waste Management》2002,4(1):12-22
This paper considers the current status of waste generation and waste treatment trends, and introduces a wide variety of policy
instruments for waste minimization at every stage of economic activity in Korea, i.e., production, distribution, and consumption.
At each stage, the Korean government has imposed a policy mix of direct regulations and economic incentives. These policy
instruments have made definite contributions to a reduction of waste generation and an increase in the recycling rate. Despite
these fruitful outcomes, there are still some shortcomings with respect to efficiency and equity. Among other aspects, this
paper examines three representative economic incentives – the charge system, the volume-based-collection fee system, and the
deposit–refund system – and identifies shortcomings in each. Some suggestions are made for the creation of better systems
of economic incentives. However, many experts insist that this kind of piecemeal change in each policy instrument is not enough
to achieve the ultimate goal of resource circulation and an environmentally friendly society, especially in Korea, which is
a country with little land, a high population density, and a high economic growth rate. Among experts, special emphasis is
placed on the activation of recycling industries to achieve these goals.
Received: April 2, 2001 / Accepted: September 10, 2001 相似文献
228.
M. Fehr 《The Environmentalist》2002,22(4):319-324
This study reports on experimentation with municipal and industrial solid waste in Brazil, on mutual inspection of municipal sanitation models in selected Spanish and Brazilian towns, and on observations of municipal solid waste (MSW) management models effective in Argentina, Great Britain, Sweden, and Germany. The diversity of management strategies inhibits technology transfer. Judging by the models inspected, Sweden and Germany appear to be best prepared for stricter European landfill diversion targets in the near future. Experimentation in Brazil has resulted in a proactive MSW management model based on divided collection, which achieves 80 percent landfill diversion. This result, surprisingly, meets and exceeds European diversion targets in a South American context. As the gap in strategy and target narrows between South America and Europe, both technology and management methods may gain intercontinental mobility and thus enhance commercial ties between the two markets in the specific branch of MSW management. 相似文献
229.
230.