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841.
对品种繁多的应急物资进行分类是科学储备应急物资的前提和基础。以应急物资的自然属性和社会属性以及突发事件的应急需求为基础,从应急物资的有效使用期限、用途、生产周期、价格、市场流通量、社会集中拥有量、突发事件的预计需求量和需求层次8个方面建立应急物资的分类指标体系;采用模糊聚类的方法对应急物资进行分类,并用经验正交函数方法确定应急物资的最佳分类数量;最后探讨了每一类应急物资的储备模式,为应急物资的科学储备提供借鉴。 相似文献
842.
宁夏40年灾害性冰雹天气分析 总被引:5,自引:0,他引:5
利用1961-2000年5-9月常规地面观测资料及相应时段的NCEP/NCAR逐日全球再分析资料,分析了宁夏灾害性冰雹天气的时空分布和环流特征,然后对74次有灾情记录的冰雹天气过程的环流背景、影响系统等进行了合成对比分析。结果表明:宁夏冰雹主要分布在南部六盘山区和北部贺兰山区,集中出现在6-7月;冰雹发生于“西高东低”环流背景下;产生冰雹天气主要有平直气流、两槽一脊、一槽一脊和一脊一槽等4种环流形势;影响系统主要有切变线、低涡和冷槽,这几种系统往往是共同作用、共同影响的;同时也表明,在不同的环流背景下,不同影响系统造成的冰雹天气落区有较大的差异。 相似文献
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846.
促进循环经济发展的税收政策 总被引:3,自引:0,他引:3
循环经济是一种全新的经济模式,它关注的是资源减量、循环及再利用的问题。介绍了国外发展循环经济所采取的税收政策,指出我国目前在该领域所存在的问题,并根据我国的实际情况,提出了促进发展循环经济的税收政策,包括:完善现有税种,开征环境保护税,建立“绿色关税”体系,尽早开征燃油税,制定激励机制,开征社会保障税。 相似文献
847.
采用强化循环高效厌氧反应器(strengthen circulation anaerobic reactor,SCAR)处理实际印染废水,在HRT=13.5 h、平均容积负荷为4.1 kg COD/(m3·d)的条件下,研究回流强度对反应器运行效果的影响。在回流比R=3和4时,反应器对COD的平均去除率最高,而由于PVA难生物降解特性,回流比对PVA的去除效率影响不大。各回流比条件下,反应器出水pH值均较进水时高,系统中未出现VFA累积现象。不同回流比条件下,反应器中颗粒污泥均保持良好沉降性能,系统对COD的去除效果与脱氢酶活性、辅酶F420之间密切相关。 相似文献
848.
Brandie Fariss Nicole DeMello Kathryn A. Powlen Christopher E. Latimer Yuta Masuda Christina M. Kennedy 《Conservation biology》2023,37(1):e13973
Efforts to devolve rights and engage Indigenous Peoples and local communities in conservation have increased the demand for evidence of the efficacy of community-based conservation (CBC) and insights into what enables its success. We examined the human well-being and environmental outcomes of a diverse set of 128 CBC projects. Over 80% of CBC projects had some positive human well-being or environmental outcomes, although just 32% achieved positive outcomes for both (i.e., combined success). We coded 57 total national-, community-, and project-level variables and controls from this set, performed random forest classification to identify the variables most important to combined success, and calculated accumulated local effects to describe their individual influence on the probability of achieving it. The best predictors of combined success were 17 variables suggestive of various recommendations and opportunities for conservation practitioners related to national contexts, community characteristics, and the implementation of various strategies and interventions informed by existing CBC frameworks. Specifically, CBC projects had higher probabilities of combined success when they occurred in national contexts supportive of local governance, confronted challenges to collective action, promoted economic diversification, and invested in various capacity-building efforts. Our results provide important insights into how to encourage greater success in CBC. 相似文献
849.
Iain Dickson Stuart H. M. Butchart Allison Catalano David Gibbons Julia P. G. Jones Katie Lee-Brooks Thomasina Oldfield David Noble Stuart Paterson Sugoto Roy Julien Semelin Paul Tinsley-Marshall Rosie Trevelyan Hannah Wauchope Sylvia Wicander William J. Sutherland 《Conservation biology》2023,37(1):e13967
Although some sectors have made significant progress in learning from failure, there is currently limited consensus on how a similar transition could best be achieved in conservation and what is required to facilitate this. One of the key enabling conditions for other sectors is a widely accepted and standardized classification system for identifying and analyzing root causes of failure. We devised a comprehensive taxonomy of root causes of failure affecting conservation projects. To develop this, we solicited examples of real-life conservation efforts that were deemed to have failed in some way, identified their underlying root causes of failure, and used these to develop a generic, 3-tier taxonomy of the ways in which projects fail, at the top of which are 6 overarching cause categories that are further divided into midlevel cause categories and specific root causes. We tested the taxonomy by asking conservation practitioners to use it to classify the causes of failure for conservation efforts they had been involved in. No significant gaps or redundancies were identified during this testing phase. We then analyzed the frequency that particular root causes were encountered by projects within this test sample, which suggested that some root causes were more likely to be encountered than others and that a small number of root causes were more likely to be encountered by projects implementing particular types of conservation action. Our taxonomy could be used to improve identification, analysis, and subsequent learning from failed conservation efforts, address some of the barriers that currently limit the ability of conservation practitioners to learn from failure, and contribute to establishing an effective culture of learning from failure within conservation. 相似文献
850.
河西走廊临泽样区土壤系统分类研究 总被引:1,自引:0,他引:1
根据《中国土壤系统分类(修订方案)》(1995),对河西走廊临泽样区土壤进行了系统分类研究,提出了临泽样区土壤系统分类方案将土壤分为4个土纲(人为土、干旱土、潜育土和雏形土),4个亚纲,5个土类和8个亚类。同时探讨了样区土壤基层分类单元之土系的划分,初步拟定了12个土系。 相似文献