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51.
The United States Department of Health and Human Services through Wayne State University (WSU) has completed a study of hazardous waste education and training in the United States. The study documents university course work and degrees as well as non-degree continuing education short courses. Major portions of the study are based on a WSU sponsored survey in which 1469 four-year degree granting institutions were contacted. Of the 732 institutions responding, 113 were identified as offering course work of some kind in hazardous waste. Information on 499 distinct non-degree short courses was also gathered and evaluated. The purpose, methodology and results of the study are summarized in this article.  相似文献   
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Prenatal diagnosis of del(11)(p13p15) was made on cultured amniotic fluid cells and confirmed on fetal skin fibroblasts after termination of pregnancy. Both irides appeared behind schedule in development by 2–3 weeks in reference to the gestational age of the fetus. It is suggested that the aniridia of the aniridia-Wilms tumour association is due to developmental arrest. Confirmation of this complex is difficult at mid-gestation without critical pathological study of the eyes.  相似文献   
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Advocates of sustainable urban development often privilege the region as a scale for coordinated action and investment. However, discourses of sustainability institutionalised through regional planning, and conflated with notions of liveability, lend themselves to recruitment by competing, and opposing, development interests. To be regionally sustainable, an individual land development should, both on-site and through its connections to other sites, contribute to overall sustainability of the region. Using examples of industrial waterfront redevelopment in metropolitan Vancouver, we show how particular urban spaces are misrepresented as lynchpins of regional sustainability. In a plan for residential redevelopment, it is claimed that sustainable redevelopment will reunite citizens with “their waterfront”, reframed as liveable, pure, clean, ecologically vital and non-industrial. At an adjacent site, it is claimed that waterfront industrial land should be protected to combat industrial sprawl. Yet, in both cases the developers have lobbied for the expansion of road transportation making the claims of regional sustainability doubtful.  相似文献   
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为揭示不同比例作物秸秆和蔬菜尾菜堆肥过程中种子毒性变化及其影响机理,开展了为期55 d的以玉米(Zea mays L.)秸秆为辅料,绿花菜(Brassica oleracea L.var.botrytis L.)尾菜为主料的工厂化条垛堆肥,分别设置加入高(湿重比4∶12)和低(湿重比1∶12)比例秸秆与尾菜的堆肥处理.测定了不同时期堆肥p H、电导率(EC)、可溶性有机碳(DOC)、硝氮(NO3--N)、氨氮(NH4+-N)、碳氮比(C/N)、大白菜种子(Brassica rapa L.)的发芽指数(Germination Index,GI)、相对生长指数(Relative Growth Index,RGI)和α-淀粉酶、蛋白酶、脂肪酶的变化.结果表明,高比例秸秆堆肥处理的高温(>55℃)持续期显著高于低比例处理.堆肥结束时两个处理的堆肥均呈碱性,且EC、DOC、NH4+-N和NO3--N含量均降低,C/N...  相似文献   
56.
The natural resource management literature documents many reasons for pursuing collaborative processes, offering useful insights on how to manage conflict and facilitate productive deliberation in complex multistakeholder collaborative efforts. Moral foundations theory and self-affirmation theory can further help collaborative efforts mitigate conflicts caused by identity threats and the identity-protective reasoning these threats provoke. Moral foundations theory suggests an approach to increase collaboration by minimizing triggering language and helping people appreciate opposing viewpoints. Self-affirmation theory suggests a practical intervention that could be used to increase collaboration by desensitizing people to identity threats and reducing defensiveness. Taken together, these theories can contribute substantially to the understanding and practice of collaboration and conflict management for conservation.  相似文献   
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A purview of waste management evolution: special emphasis on USA   总被引:4,自引:0,他引:4  
The generation of waste in urban regions over time is seen to impact the balance of anthropogenic and natural resources. Various national and international initiatives to manage urban solid waste are in place and has thus have evolved at present to form an assortment of different subcomponents involving environmental, administrative, regulatory, scientific, market, technology, and socio-economic factors, which has increasing bearing on the US due to its volume and nature of discards. This paper draws together the various aspects of municipal solid waste (MSW) management as it evolved, particularly in the American society through reviewing works and findings. In many parts of the country, waste management at present, primarily involves landfilling, incineration with and without energy recovery, recycling and composting. Legislation, nature of wastes and market trends continue to redefine management operations and its responsibilities and impacts. Complexities are added to it by the nature of urban development as well. New studies and concepts like 3Rs, cradle-to-cradle, industrial ecology, and integrated waste management are adding new dimensions for solving waste problems towards achieving sustainable resource use. Local initiatives, both public and private are in the forefront of adopting alternate waste management procedures. The assistance from various government and private bodies, supporting shifts in waste management approaches, have immense value, as according to the new paradigms, nothing goes to waste.  相似文献   
60.
Recently several regional air quality projects were carried out to support the negotiation under the Clean Air For Europe (CAFE) programme by predicting the impact of emission control policies with an ensemble of models. Within these projects, CITYDELTA and EURODELTA, the fate of air quality at the scale of European cities or that of the European continent was studied using several models. In this article we focus on the results of EURODELTA. The predictive skill of the ensemble of models is described for ozone, nitrogen dioxide and secondary inorganic compounds, and the uncertainty in air quality modelling is examined through the model ensemble spread of concentrations.For ozone daily maxima the ensemble spread origin differs from one region to another. In the neighbourhood of cities or in mountainous areas the spread of predicted values does not span the range of observed data, due to poorly resolved emissions or complex-terrain meteorology. By contrast in Atlantic and North Sea coastal areas the spread of predicted values is found to be larger than the observations. This is attributed to large differences in the boundary conditions used in the different models. For NO2 daily averages the ensemble spread is generally too small compared with observations. This is because models miss highest values occurring in stagnant meteorology in stable boundary layers near cities. For secondary particulate matter compounds the simulated concentration spread is more balanced, observations falling nearly equiprobably within the ensemble, and the spread originates both from meteorology and aerosol chemistry and thermodynamics.  相似文献   
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