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641.
In the course of a 2-year predictive testing programme for Huntington's disease (HD), six couples from a total of 52 applicants requested prenatal testing. In each case, the pregnancy was in the first or second trimester when the couples were referred for DNA diagnosis. In five cases, exclusion testing was offered; in one case, a person at risk with an increased risk of being a gene carrier requested prenatal diagnosis. In all cases, informative markers for prenatal testing could be determined. Whenever possible, the newer technique of polymerase chain reaction (PCR) for D4S125 was applied to perform rapid prenatal diagnosis. Two couples withdrew before chorionic villus sampling was undertaken; prenatal diagnosis was completed in the remaining four cases. After exclusion testing, two pregnancies were determined to have an increased risk and two fetuses to have a low risk of being HD gene carriers. 相似文献
642.
The Environmental Auditing Roundtable (EAR) is the single largest professional organization in the world, representing over 900 members. Built on a tradition of promoting environmental auditing through openly sharing experiences in the field of safety, health, and environmental auditing, the organization in recent years has significantly expanded its influence on auditing practices both nationally and internationally by monitoring audit activities and participating in the development of audit policy, regulation, standardization, and the certification of environmental auditors. This article describes the origin and evolution of the organization from meeting the needs of the membership to addressing the needs of external national and international stakeholders. 相似文献
643.
Many organizations in environmental fields stand to benefit from the use of a geographic information system (GIS). Selecting
a GIS to implement within an organization can be a difficult task that is often required of people with little experience
using a GIS. A framework for evaluating competing GIS considers cost, functionality, ease of use, future stability, development
potential, support availability, and maintenance costs. Initial cost involves more than the actual purchase price of hardware
and software; it includes the cost of building the data base and training users within the organization. Functionality refers
to the depth and breadth of capabilities of a GIS. Issues involved in evaluating functionality include the appropriateness
of raster vs vector processing and the ability to add your own software. Ease of use is important, but there is generally
a trade-off with functionality. The degree of centralization of use of the GIS within the organization affects requirements
for ease of use. GIS are rapidly evolving, and as a result it is important to select a system with high potential for future
development. With the proliferation of companies offering GIS it is important to select one that is likely to survive and
prosper. Similarly, the ability to find support in the forms of technical help, advice, and possibly even skilled employees
can be significant. 相似文献
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Discussions about the potential role of academic and research institutions in regional sustainability initiatives (RSIs) inevitably raise the issue of the role of science in society in general. In democratic societies, it can be argued that science–society relationships should be based on establishing and institutionalizing mutual dialogues, making public concerns not only visible but the public as equal partner. In order to fulfil the social responsibilities of academic institutions involved in RSIs through establishing dialogues with diverse stakeholders, a possible methodology is conducting participatory action research (PAR) combined with the educational model of service learning. The PAR project reported here aims at facilitating a bottom-up, micro-region level sustainability planning and development process in one of the most socio-economically disadvantaged rural areas of north-east Hungary. Some of the main results of this university–community partnership were its contribution to sustainability, including the activation of local capabilities and networking across various local stakeholder groups through various small-scale projects and the co-production of a socially grounded and landscape-based rural development plan for the micro-region. 相似文献
647.
Francesca Romana Grati Denise Molina Gomes Jose Carlos Pinto B. Ferreira Celine Dupont Viola Alesi Laetitia Gouas Nina Horelli-Kuitunen Kwong Wai Choy Sandra García-Herrero Alberto Gonzalez de la Vega Krzysztof Piotrowski Rita Genesio Gloria Queipo Barbara Malvestiti Bérénice Hervé Brigitte Benzacken Antonio Novelli Philippe Vago Kirsi Piippo Tak Yeung Leung Federico Maggi Thibault Quibel Anne Claude Tabet Giuseppe Simoni François Vialard 《黑龙江环境通报》2015,35(8):801-809
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Judy Z. Drexier Barbara L. Bedford Arthur T DeGaetano Donald I. Siegel 《Journal of the American Water Resources Association》1999,35(4):753-769
ABSTRACT: Few water budgets exist for specific types of wetlands such as peatlands, even though such information provides the basis from which to investigate linkages between wetlands and upland ecosystems. In this study, we first determined the water budget and then estimated nutrient loading from an upland farm field into a 1.5 ha, kettle-block peatland. The wetland contains highly anisotropic peat and has no distinct, active layer of groundwater flow. We estimated the depth of the active layer using Fick's law of diffusion and quantified groundwater flow using a chemical mass balance model. Evapotranspiration was determined using MORECS, a semi-physical model based on the Penman-Monteith approach. Precipitation and surface outflow were measured using physical means. Groundwater provided the major inflow, 84 percent (44,418 m3) in 1993 and 88 percent (68,311 m3) in 1994. Surface outflow represented 54 percent (28,763 m3) of total outflows in 1993 and 48 percent (37,078 m3) in 1994. A comparison of several published water budgets for wetlands and lakes showed that error estimates for hydrologic components in this study are well within the range of error estimates calculated in other studies. Groundwater inflow estimates and nutrient concentrations of three springs were used to estimate agricultural nutrient loading to the site. During the study period, nutrient loading into the peatland via groundwater discharge averaged 24.74 kg K ha-1, 1.83 kg total inorganic P had, and 21.81 kg NO3-N ha-1. 相似文献