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251.
当前循环经济的研究工作在中国深入展开,与此相适应的循环经济规划的编制和实施工作紧密进行。文章围绕规划的理论基础、现实意义,以及基本元素构成进行介绍。就开展规划编制工作的现状展开综述,归纳所取得的成绩与存在的缺陷、待解决或完善的内容。从我国实际并行的若干规划出发.初步阐释其与循环经济规划协调的原理。现阶段的循环经济探索主要还是基于环境。其可能的经济属性的严重探完不足。试行循环经济规划之后增加的再生成本等其他相关问题在后一阶段的规划推进中需深入考虑。 相似文献
252.
253.
当前生态文明指标体系研究和实践中,一方面生态文明指标体系和生态文明指数构建方法不尽相同,另一方面刻意追求统一的指标体系而忽视了不同行政层级间的差异性,对层级间指标衔接等问题缺乏考虑。依照生态文明内涵以及十八大尤其是十八届三中全会关于生态文明建设尤其是生态文明考核指标要求,提出各行政层级构建“橄榄型”生态文明建设指标框架体系。该指标体系强调国家的顶层宏观引导作用,并以市县级生态文明建设指标体系为基础,向上构建省级生态文明建设指标体系,向下构建乡镇级生态文明建设指标体系,体现“国家—省—市县—乡镇”之间的整体性、衔接性、协调性,真正反映生态文明建设是“自上而下引导力”和“自下而上推动力”的合力作用的结果,服务于我国生态文明建设的持续开展和长效管理。 相似文献
254.
为研究套箍加固RC轴压中长柱的承载力理论计算分析方法,采用切线模量理论,根据材料本构关系和内外力平衡条件,推导了套箍加固RC轴压中长柱的弹塑性稳定承载力计算方法。将理论计算结果与试验结果进行了对比分析,结果表明:理论计算值均低于实测值,且二者的偏差在15%以内。根据所推导的计算分析方法,研究了核心柱初始荷载水平β、柱子长细比l0/b、套箍层混凝土强度、套箍层配筋量四种参数对加固柱承载力Nu的影响规律,结果表明:Nu总体上随β增大而减小,当β<0.7时,减小趋势不够明显,β>0.7后,减小趋势变得明显;l0/b对Nu有明显影响,Nu随l0/b的增大而减小,但二者不是线性关系;Nu随套箍层混凝土强度提高而增大,随套箍层配筋量增大而增大。 相似文献
255.
Linked river basin and coastal water models were applied to analyse the effects of an optimal nitrogen management scenario
in the Oder/Odra river basin on water quality in the Oder (Szczecin) Lagoon and the Pomeranian Bay (Baltic Sea). This scenario
would reduce nitrogen loads into the coastal waters by about 35%, a level which is similar to the load of the late 1960’s.
During summer the primary production and algae biomass in the Oder estuary is limited by nitrogen, which makes a nitrogen
management reasonable. The comparison of the late 1960’s and the mid 1990’s shows that an optimal nitrogen management has
positive effects on coastal water quality and algae biomass. However, this realistic nitrogen reduction scenario would not
ensure a good coastal water quality according to the European Water Framework Directive. A good water quality in the river
will not be sufficient to ensure a good water quality in the lagoon. Nitrogen load reductions bear the risk of increased potentially
toxic, blue-green algae blooms, especially in the Baltic coastal sea. However, to reach water quality improvements in lagoons
and inner coastal waters, nitrogen cuts are necessary. A mere focus on phosphorus is not sufficient. 相似文献
256.
Illegal dumping of solid waste is a matter of recent concern because of its numerous impacts. The regulatory framework of the European Union and Italy is disclosed. Degradation of air, bodies of water, groundwater, and soil can occur in the illegal landfill and surrounding sites causing e.g. acidification, eutrophication global warming and photochemical smog. Animals and plants are subjected to landfill borne pollutants that can damage them seriously. Landfill pollutants have also harmful effects on human beings raising the risk of illness such as cancer and cardiorespiratory disease. Finally illegal landfilling practices lead to economical, aesthetic impacts, and sociological discomfort that lead to multiple collective actions, blockages, and information campaigns, rising sense of belonging. 相似文献
257.
采用溶剂热法合成了金属有机骨架材料UiO-66。通过XRD、SEM、FTIR对其进行了表征。考察了UiO-66对溶液中NO_3~-的吸附性能。实验结果表明,加入冰乙酸作调节剂后,得到的UiO-66晶体形貌均匀,直径在100nm左右,结晶度更好。在初始溶液pH为5、反应温度为30℃的条件下,UiO-66吸附NO_3~-反应90 min后,吸附达到平衡,平衡吸附量为39.67 mg/g。UiO-66吸附NO_3~-的吸附行为符合Freundlich等温线和准二级动力学吸附模型。吸附作用主要是材料中金属位点Zr对NO_3~-的静电吸附。UiO-66材料具有良好的再生性能,可重复使用。 相似文献
258.
This paper presents the results of an analysis of deliberative norms in the framework for Environmental Impact Assessment (EIA) in roads planning in Sweden. The more specific question is how this framework has responded to the shift towards more deliberative approaches to planning and decision making, advocated in planning theory and policy literature over the last decade. The analysis, which compares the current framework and guidance with an earlier iteration, identifies a shift towards deliberation; deliberative norms are present, and even dominate recent guidance. However, an instrumental norm permeates both the former and the current guidance, suggesting that even as a language of consultation is replaced by one of deliberation, the intention remains to secure and legitimise a smooth development pathway. Evidence from interviews with professionals working in the Swedish EIA system highlights the difficulties of navigating these uncertainties in practice. By opening up critical analysis of deliberative norms as they shape the conditions for practice, this study contributes to the continuous development of planning practice, by supporting a more normatively reflexive approach to framework-design. 相似文献
259.
Anoxic biodegradation of dimethyl phthalate (DMP) by activated sludge cultures under nitrate-reducing conditions 总被引:3,自引:0,他引:3
Worldwide extensive use of plasticized plastics has resulted in phthalates pollution in different environment. Nitrates from industry and agriculture are also widely disseminated in the soils, natural waters and wastewaters. Dimethyl phthalate (DMP) biodegradation by activated sludge cultures under nitrate-reducing conditions was investigated. Under one optimized condition, DMP was biodegraded from 102.20 mg/L to undetectable level in 56 h under anoxic conditions and its reaction fitted well with the first-order kinetics. Using the high-performance liquid chromatography (HPLC) and liquid chromatography mass spectrometry (LC-MS) analysis, mono-methyl phthalate (MMP) and phthalic acid (PA) were detected as the major intermediates of DMP biodegradation. When combined with the determination of chemical oxygen demand (CODCr) removal capacity and pH, DMP was found to be mineralized completely under anoxic conditions. The biodegradation pathway was proposed as DMP → MMP → PA → … → CO2 H2O.The molar ratio of DMP to nitrate consumed was found to be 9.0:1, which agrees well with the theoretical stoichiometric values of DMP biodegradation by nitrate-reducing bacteria. The results of the non-linear simulation showed that the optimum pH and temperature for the degradation were 7.56 and 31.4℃, respectively. 相似文献
260.