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811.
Policies that arise out of conflict or collaboration between specific interest groups and government agencies are often explained
by theoretical constructs that fall under the umbrella of group theory. Triangulation theory is one of these constructs and
serves to explain the mutuality of interests that exist between government agencies and interest groups expressed as points
linking geometric forms. Conflict tends to occur when competing interest groups are excluded from the linkage, in this case
between the opponents and proponents of hormone herbicides in the Tala area in Natal, South Africa. In opposition to the use
of hormone herbicides were vegetable farmers and their supporters: in linked support were agricultural interest groups who
used hormone herbicides, the manufacturers of the herbicides, and the government agency responsible for agriculture. Because
of the influence exerted through mutual support by the proponents of hormone herbicides, the formulation of policy decisions
directed towards the resolution of the conflict was delayed. When the minister of agriculture finally intervened, the policy
decisions were designed to secure the support of those opposing the use of hormone herbicides by introducing issues that cut
across those maintaining the discord. 相似文献
812.
Mark Moody-Stuart 《生态毒理学报》2003,25(2):12-15
商业已经为可持续性发展进程建立了伙伴关系的基础 .通过确立目标和公开报告为实现这些目标应做的准备,可以保证建立工作伙伴关系愿望的实现 .在目前还没有可持续发展经济活动的地区,引进大大小小的商业企业 .市场是重要的,但是结构的调整也同样重要 .志愿的努力推动着事物向前发展 .为了全球的贸易、金融和环境的发展,有必要形成国际构架,商业界就需要与其他各界共同奋斗,确保对每一个单独的国家和企业的管理符合<全球契约>订立的基本标准 . 相似文献
813.
814.
Remediation results depend on thorough consideration of all the forces that influence contaminant behavior, including how the contaminant is distributed and the site's hydrogeology, as well as the physical, chemical, and biological factors involved in contaminant mobility and persistence. This information supports a cleanup project's initial investigation, helping decide the goals of the later remediation method, the usefulness of specific technologies, and the method's ultimate performance. This article discusses how the principal environmental and chemical processes influence contaminant fate and transport and explores four case histories that illustrate how that influence can help predict whether a project's goals are achievable, whether the project is needed at all, and whether those goals were actually achieved. 相似文献
815.
Analytical procedures for the determination of nine organic booster biocides which are currently licensed for use in marine antifouling paints, and are thought likely to occur at concentrations in the ng 1−1 range in estuarine water samples, are reviewed. A robust multiresidue method for the determination of four compounds (chlorothalonil, dichlofluanid, diuron and Irgarol 1051) is suggested. A route for the development of a method for the analysis of zinc pyrithione is outlined, based on an extraction method and subsequent derivatisation prior to determination by HPLC with fluorescence detection. Methodology for Zineb, Kathon 5287, TCMS pyridine and TCMTB is less clearly defined. 相似文献
816.
Mark Pyron 《Behavioral ecology and sociobiology》1995,37(6):407-412
Neither size nor breeding color correlated with spawning success of male orangethroat darters, Etheostoma spectabile (Pisces, Percidae), under natural field conditions. When females were presented experimentally with a simultaneous choice they spent no more time in proximity to large than small males, and were subsequently no more likely to spawn with large than with small males. Females also displayed no preference for bright versus dull males. Males and females did not differ significantly in size. Etheostoma spectabile may lack sexual size dimorphism as a result of the lack of female choice for size and the ineffectiveness of male attempts to monopolize females, or selection may be for increased size of females. Males are not dwarfs because of sperm competition. Contest competition among males appeared to be important in initiating spawnings but many males obtained spawnings by participating in ongoing spawning events. Etheostoma spectabile is an example of a sexually dimorphic species with no evident female preference for male size or color. 相似文献
817.
An experiment was performed on six species of trees to determine the feasibility of remediating groundwater contaminated with an agricultural herbicide, bentazon, at a site in southern Louisiana. Fate studies on bentazon support that it is translocated to the plant leaves where it is degraded by photolysis to lower-order derivative compounds within short periods of time. Both transpiration observations and dosing tests suggest that the most favorable phreatophyte and tolerant specie of tree to bentazon exposure was the black willow (Salix nigra). 相似文献
818.
The former Nebraska Ordnance Plant site in east-central Nebraska was included on the National Priorities List because of explosives and trichloroethene contamination. The preferred groundwater remedy includes hydraulic containment of the contaminated groundwater and focused extraction of the more highly contaminated groundwater as components of the remedial action. The purpose of hydraulic containment is to stop the spread of contamination, while the more aggressive focused extraction will be used to speed up the remediation and reduce total cleanup costs. This case study illustrates how straightforward groundwater models were combined with uncertainty analysis to select a precise definition of the focused extraction areas. The purpose of the analysis was to reduce ultimate remediation costs, given the significant uncertainty associated with the estimated remediation times. The selected definition provides a basis for more sophisticated groundwater modeling, the goal of which was to locate extraction wells and define their flow rates. The batch flushing model provided the governing equations, and Monte Carlo analysis was used for the uncertainty analysis. All of the analysis was performed on a personal computer using commercially available software. 相似文献
819.
820.
Mark Weinblatt M.D. Boris Petrikovsky Martin Bialer Joseph Kochen Rita Harper 《黑龙江环境通报》1994,14(9):892-896
A fetus with absent radii in both forearms was discovered on routine ultrasound examination performed at 18 weeks of pregnancy. No other significant abnormalities were found, and no signs of haemorrhage were detected. Serial ultrasound examinations revealed no evidence of fetal internal bleeding. At 37 weeks of pregnancy, a CBC obtained by cordocentesis under ultrasound guidance confirmed the diagnosis of thrombocytopenia absent radii (TAR) syndrome. Apheresis platelets were transfused into the umbilical vein to correct the thrombocytopenia and was followed by an uncomplicated delivery. No bleeding was encountered during the remainder of the baby's neonatal course. We conclude that TAR syndrome can be readily identified prenatally on sonogram, and if severe thrombocytopenia is confirmed by cordocentesis, platelets should be transfused to diminish the risk of serious internal bleeding during and immediately after delivery. 相似文献