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831.
ABSTRACT: In May 1993, a single-family home and adjoining information center opened to the public at the Desert Botanical Garden in Phoenix, Arizona. Desert House is designed as an example of what can be achieved today using available technology to improve residential water and energy efficiency. The home is expected to reduce water and energy use by 40 percent compared with that for the typical three-bedroom, single-family residence in the Phoenix area. Water-conserving features include: landscape design employing low-water use plants, minimum turf area, mulch around plants to reduce evaporation, and drip irrigation system; spa cover for evaporation reduction; rainwater harvesting; low-flow shower heads, faucets, and toilets; and graywater reuse system. The home will be occupied by a family and monitored for water and energy use by computer. Visitors are able to access real time water and energy use data about the home, as well as tour the information center, technical exhibits, surrounding landscape, and the home when it is open (one afternoon a week).  相似文献   
832.
ABSTRACT: This paper summarizes key provisions of the Clinton Administration's proposals for change in the Clean Water Act. Two of the important themes for change are tougher controls for non-point source pollution and the use of market-based instruments. A detailed analysis of market-based abatement suggests limited potential for reducing costs. The keys to nonpoint source pollution control are clearer definition of property rights combined with changes in government programs that encourage polluting activities.  相似文献   
833.
834.
No one remedial technology is best suited to treat every groundwater contaminant plume. This article describes how pilot testing and analytical evaluation targeted selection of two treatment technologies, UV peroxidation and air stripping, to be used in series to create a synergistic, cost-effective pump-and-treat system for the removal of VOCs from groundwater. Pilot plant size equipment was employed to treat the VOC-contaminated groundwater in order to obtain site-specific reaction rates and to develop full-scale design parameters. It was found that by using the two treatment technologies in combination, the influent concentration of 2,000 ppb total VOCs could be reduced to less than 1 ppb, thus meeting drinking water standards.  相似文献   
835.
ABSTRACT: The development of a nondegradation policy for high quality waters is a complex and often controversial process. This paper discusses the development of a nondegradation policy for two components of the National Wild and Scenic Rivers System. Water quality in these reaches of the Delaware River is threatened by rapid growth and development and the cumulative impacts from numerous wastewater discharges and nonpoint sources of pollution. The Delaware River Basin Commission, with assistance from its member states and the National Park Service, conducted a highly public, six-year planning process to develop a nondegradation policy that protected existing water quality without impinging upon local and state economic development objectives. The resulting non-degradation policy includes such features as numeric definitions of existing water quality and measurable change; stringent point source requirements; nonpoint source requirements including watershed planning requirements; and other water quality management policies.  相似文献   
836.
ABSTRACT: A streamflow duration curve illustrates the relationship between the frequency and magnitude of streamflow. Flow duration curves have a long history in the field of water-resource engineering and have been used to solve problems in water-quality management, hydropower, instream flow methodologies, water-use planning, flood control, and river and reservoir sedimentation, and for scientific comparisons of streamflow characteristics across watersheds. This paper reviews traditional applications and provides extensions to some new applications, including water allocation, wasteload allocation, river and wetland inundation mapping, and the economic selection of a water-resource project.  相似文献   
837.
Transformational leadership theory was examined in 89 schools in Singapore using a split sample technique (N = 846 teachers). The study sought to examine the influence of transformational leader behavior by school principals as it related to organizational commitment, organizational citizenship behavior, teacher satisfaction with leader, and student academic performance. Attitudinal and behavioral data were collected from both teachers and principals; student academic performance was collected from school records. School level analyses showed that transformational leadership had significant add-on effects to transactional leadership in the prediction of organizational commitment, organizational citizenship behavior, and teacher satisfaction. Moreover, transformational leadership was found to have indirect effects on student academic achievement. Finally, it was found that transactional leadership had little add-on effect on transformational leadership in predicting outcomes. Implications and directions for future research are discussed.  相似文献   
838.
The international conference on The African Experience with River Basin Development challenged participants to pursue a critical discussion of the record to date on approaches to river basin development and to propose appropriate strategies for the future. During the conference, special focus was given to the institutional requirements for planning, implementing and evaluating those strategies which benefit large numbers of people through increased production, enterprise development and employment generations in an environmentally sound fashion. It was noted that serious negative environmental and socio-economic effects have followed in the wake of African dam construction and the creation of large man-made lakes. The conference produced a short-list of general priorities for improving river basin development in Africa.  相似文献   
839.
Empirical tests have indicated that following the Vroom-Yetton Normative Model of leadership predicts reliably to successful managerial decision-making. However, it does not consider the kind of social interaction among decision makers. Recent experiments have demonstrated that controversy constructively discussed can facilitate decision-making. To see whether constructive controversy can supplement the Vroom-Yetton model, 58 managers enrolled in an executive-level MBA programme described a successful and unsuccessful decision-making experience by answering the Vroom-Yetton questions and by indicating the extent those involved in making the decision experienced constructive controversy. Results indicate that both the Vroom-Yetton model and constructive controversy are significantly related to successful decision-making. A regression analysis indicated that constructive controversy accounted for 45 per cent of the variance of decision success whereas the Vroom-Yetton model accounted for 5 per cent. While the Vroom-Yetton model is useful at the preplanning stage for choosing a decision style, much greater contribution is provided by constructive discussions of opposing opinions when actually generating the decision.  相似文献   
840.
Ten streams in the eastern Sierra Nevada, California, were classified into six geomorphic valley types and sampled to determine environmental and riparian vegetation conditions. The geomorphic valley types were relatively uniform geologically and hydrologically, collectively representing the range of stream environments in the region. There were significant associations between the geomorphic valley types and riparian community composition. These geomorphic-vegetation units are landscape elements which comprise the riparian ecosystems in the region. They differ in their ecological charactersitics and sensitivity to management. The system of landscape elements can be used to classify streams for the purposes of resource inventory, detailed ecological studies, and impact prediction.  相似文献   
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