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371.
372.
基于调节聚焦理论的生物农药推广有效性研究 总被引:2,自引:0,他引:2
化学农药在提高单位耕地面积农产品产量和效益的同时,由于过量施用、利用效率低下等污染了生态环境、危害农产品安全和损害消费者健康等问题,而具有低残留、低污染和环境友好性优势的生物农药逐渐得到公共部门和业界的重视。但生物农药能否得到大范围推广和施用,关键在于能否改变农户的农药施用行为和农药生产企业的积极参与。由于生物农药施用涉及农户的当前利益和长期利益、个人利益和社会利益等相关因素,使农户的农药施用决策具有突出的心理距离属性。本文引入调节聚焦理论,建立了心理距离与农户农药施用决策和心理动机的关系,实证研究生物农药推广对农户农药施用决策、支付愿意(WTP)、农药生产企业态度和再次施用意愿的影响。结论如下:1施用生物农药给农户带来的收益是长期的、全社会的和不确定的,而多数农户农药施用决策所考虑的利益是当前的、私人的。因此,二者在心理距离、调节聚焦以及利益追求方面是不匹配的,这揭示了当前生物农药推广过程中出现的"叫好不叫座"的原因;2农药生产企业能够从生物农药推广中获利。如果生物农药推广得当,将会提高农户对生物农药以及农药生产企业的积极评价,其对生物农药的愿意支付价格和再次施用意愿也会提升;3调节聚集信息诉求和心理距离的匹配,对农户生物农药施用决策存在显著影响。当预防(或促进)聚焦信息诉求与近(或远)心理距离匹配时,农户对生物农药信息诉求的认同度较高,施用意愿也更高。因此,要提高生物农药的推广效果,针对农户农药施用决策具有近心理距离的特点,公共部门及农药生产企业在推广生物农药时应该强化预防聚焦信息,而弱化促进聚焦信息;此外,生物农药推广过程中,公共部门及农药生产企业也可以通过宣传策略,延长农户农药施用决策时的心理距离与改善生态环境的促进聚焦目标相匹配,从而提高农户施用生物农药的积极性。 相似文献
373.
实施工业污水排放的有效监管是水环境保护的重要环节。为借鉴国内外相关领域的理论和实践经验,促进我国监管制度的完善。从监管理论、委托-代理框架下激励监管理论以及工业水环境监管三方面的研究进展进行综述。 相似文献
374.
375.
Hypotheses relating the behavior of voles to their population cycles often assume that the rate of social interaction increases
with population density. To test this assumption, we examined the frequency of social interactions in a population of prairie
voles (Microtus ochrogaster) over a 7-year period. In addition, we characterized space use by resident animals, patterns of visitation by nonresidents
to nests, and participants in social interactions. Social groups within the population typically displayed little overlap
in their use of space, even at high population densities. Nevertheless, nonresidents, particularly wandering males, were captured
as visitors at nests. The number of visits per social group did not increase in a simple linear manner with population density
and was particularly variable when there were fewer than 100 animals/ha. At such times, more single females and fewer pairs
received visits from males than expected based on the frequency of occurrence of these groups in the population; a similar
pattern was noted during periods of high population density (≥100 animals/ha) but the comparisons failed to reach statistical
significance. Furthermore, at high population density, more communal groups received visits from females than expected. Patterns
of visitation to communal groups were influenced by the number of adult male residents (winter only), but not by the number
of adult female residents or presence of philopatric female offspring. These data indicate that the frequency of social contact
in prairie voles does not increase linearly with population density and is influenced by the spacing and possible mate-guarding
behavior of resident animals.
Received: 7 January 1998 / Accepted after revision: 16 May 1998 相似文献
376.
Human health is greatly affected by inadequate access to sufficient and safe drinking water, especially in low and middle-income countries. Drinking water governance improvements may be one way to better drinking water quality. Over the past decade, many projects and international organizations have been dedicated to water governance; however, water governance in the drinking water sector is understudied and how to improve water governance remains unclear. We analyze drinking water governance challenges in three countries – Brazil, Ecuador, and Malawi – as perceived by government, service providers, and civil society organizations. A mixed methods approach was used: a clustering model was used for country selection and qualitative semi-structured interviews were used with direct observation in data collection. The clustering model integrated political, economic, social and environmental variables that impact water sector performance, to group countries. Brazil, Ecuador and Malawi were selected with the model so as to represent the diversity of the clusters. This comparative case study is important because similar challenges are identified in the drinking water sectors of each country; while, the countries represent diverse socio-economic and political contexts, and the case selection process provides generalizability to our results. We find that access to safe water could be improved if certain water governance challenges were addressed: coordination and data sharing between ministries that deal with drinking water services; monitoring and enforcement of water quality laws; and sufficient technical capacity to improve administrative and technical management of water services at the local level. From an analysis of our field research, we also developed a conceptual framework that identifies policy levers that could be used to influence governance of drinking water quality on national and sub-national levels, and the relationships between these levers. 相似文献
377.
378.
在采场均压防灭火实验室模型模拟实验的基础上 ,总结了煤峪口矿现场实施火区的调压工艺技术。该技术包括利用调压气室平衡火区风压、提高工作面风压和堵塞地表裂隙 3项调压措施 ,其防灭火效果十分显著。在这 3项措施中 ,无论是工作面升压或气室调压失效 ,此时填堵裂隙工程则会发挥重要作用 相似文献
379.
环境保护与国际竞争力 总被引:7,自引:0,他引:7
赵细康 《中国人口.资源与环境》2001,11(4):12-16
本文在对环境保护与国际竞争力关系进行梳理的基础上,介绍了相关的研究思路与方法,总结和提出了环境保护与国际竞争力的三个基本理论,并对有关的理论进行了评述。 相似文献
380.
Hal T. Nelson 《Journal of Environmental Planning and Management》2008,51(4):581-596
Complex relationships exist between programs to reduce carbon dioxide (CO2) from the electricity sector and programs to promote renewable electricity generation. Simulation modeling of three scenarios in the UK electricity sector are used to identify potential interactions between these programs. A strict CO2 cap can result in a renewable electricity requirement being easily met. Conversely, the renewables quota could be required under low natural gas prices to keep electricity suppliers from switching from coal to gas. Similarly, CO2 trading can reduce renewables deployment levels because purchased CO2 allowances replace renewables. Therefore, both programs are required to ensure CO2 and renewables goals. The planning implications for administrative procedures and renewables subsidies are also discussed. 相似文献