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391.
基于水贫乏指数的长江流域水资源安全评价 总被引:1,自引:0,他引:1
针对长江流域水资源安全问题,选取水贫乏指数作为评估水资源安全的指标。综合考虑影响水资源安全的关键因素,选取了水资源状况、供水设施状况、利用能力、利用效率和水环境5个子系统共22个分指标,建立了水资源安全评价指标体系。采用改进的水贫乏指数计算方法,对长江流域各省级行政区的水资源安全现状进行了评估,并简要分析了导致水资源安全状况恶化的原因。研究结果表明,水贫乏指数能够较好的反映水资源安全所涉及到的社会、经济、资源、环境等诸多方面的状况,为水资源安全评估提供了有益借鉴。 相似文献
392.
实施长江经济带战略对推动我国经济发展具有重要的意义,而长江经济带创新能力的提升成为其发展的关键。基于标准差指数、变差系数、区位基尼系数和集中度指数的定量研究方法,研究长江经济带在城市群级、省级和市级多尺度上的区域创新差异及原因。研究表明:各尺度区域创新差异均呈现出持续增长趋势,并且区域创新差异随着区域尺度的增加而增加。影响长江经济带创新差异的各个区域尺度的主要原因各不相同,影响城市群创新差异的主要原因是社会环境因素,影响省域创新差异的主要原因是经济环境因素,影响城市创新差异的主要原因是对外开放因素。创新集聚随着区域尺度的增大而减小。长江中游和成渝城市群正处于创新活动向中心城市集聚阶段,而长江三角洲城市群进入创新活动的扩散阶段,并且长江三角洲城市群将形成巨大的创新集聚系统。 相似文献
393.
旅游发展能够有效匹配贫困人口的资源禀赋,是产业扶贫的重要支撑。为更好地发挥旅游的减贫效用,本文基于旅游波动和风险管理视角对旅游发展与贫困减缓的多样化关联进行了逻辑统一,在使用HP滤波方法测度旅游需求波动的基础上,使用门限面板模型对2000-2013年中国旅游发展的非线性减贫效应进行了实证检验。实证结果显示:旅游波动是影响旅游发展减贫效应的重要因素,但国内旅游波动和入境旅游波动的减贫效应存在异质性。国内旅游波动主要体现为上行波动,能够在增长的稳定预期下,有助于旅游企业和包括贫困人口在内的旅游从业者进行专业化供给,从而有助于减贫。旅游发展的减贫效应体现出双门限的非线性特征,在旅游发展的初始阶段,并未能体现出显著的减贫效果,越过第一个门限值后,旅游减贫效应开始凸显,但在第二门限值之后,处于第三阶段旅游发展减贫弹性递减。因此,旅游产业具备成为阶段性重要减贫动力来源的潜力,但在旅游扶贫政策的制定和实施中,应秉持辩证和动态视角,当意识到旅游减贫效应已经步入递减区间时,要进行主动、系统、综合的风险管理。理解外部环境变化对旅游发展冲击的潜在结果,通过旅游需求结构和产业结构的调整提升贫困人口应对风险冲击的韧性,并通过互助、保险等风险应对手段,促进资源在不同风险状态之间的转移,提升旅游减贫绩效。 相似文献
394.
Stefan Bouzarovski Sergio Tirado Herrero Saska Petrova Diana Ürge-Vorsatz 《Local Environment》2016,21(9):1151-1170
This paper focuses on the embeddedness of energy poverty – understood as the inability to secure a socially and materially necessitated level of energy services in the home – in the socio-technical legacies inherited from past development trajectories, as well as broader economic and institutional landscapes. Using Hungary as an example, we explore the recent expansion of energy poverty across different demographic and income groups. While much of the mainstream literature focuses on cases where energy poverty affects distinct social groups and issues, our analyses examine the systemic implications of a form of deprivation that involves a much wider range of social and spatial strata. We develop a framework that highlights the different ways in which inadequate access to energy services has resulted in the emergence of new political reconfigurations among a variety of actors, while prompting the articulation of household strategies with far-reaching structural consequences. 相似文献
395.
Margaret Wilder Diana Liverman Laurel Bellante Tracey Osborne 《Local Environment》2016,21(11):1332-1353
This article examines the “climate gap” in the Southwest US (Arizona and New Mexico), referring to the “disproportionate and unequal implications of climate change and climate change mitigation” for “people of color and the poor” [Shonkoff, S.B., et al., 2011. The climate gap: environmental health and equity implications of climate change mitigation policies in California. Climatic Change, 109 (Suppl. 1), S485–S503]. The climate and poverty relationship is examined using multi-scaled analysis across three indicators of climate vulnerability, focusing on connections to health, food, and energy during the period 2010–2012. We provide an overview of climate-related social vulnerability in the Southwest based on available federal, state, and county-level census data. We then summarise the results from a stakeholder workshop and in-depth interviews about climate vulnerabilities with social service providers in southern Arizona. We identify a significant Southwest climate gap based on census data and interview findings about climate vulnerability especially relating to high levels of poverty, health disparities, and increasing costs for energy, water, and food. We find that grassroots and community organisations have mobilised to respond to climate and social vulnerability, yet resources for mitigation and adaptation are insufficient given the high level of need. Confronting a changing climate that is projected to be hotter, drier, and with the potential to reach new thresholds, we suggest that more research needs to be done to understand the social and spatial characteristics of climate risk and how low-income populations embody and experience climate risk, and adapt to a changing climate. 相似文献
396.
圆盘式脱水机是近年来新发展的一种石膏脱水设备,以国内某2×660 MW机组电厂为例,针对新式的圆盘式脱水机和传统的皮带式脱水机从经济性和技术性进行了对比分析,结果发现圆盘式脱水机在长期运行后有着较大的经济和技术优势。 相似文献
397.
398.
399.
Thomas L. Traynor 《Journal of Safety Research》2009,40(6):421-426
Introduction
A state by year panel is analyzed to simultaneously explore the statistical correlation between state level traffic fatality rates and state level behavioral regulations regarding teen licensing, seat belt use, and driving under the influence (DUI) in a model that also controls for other correlates.Method
By including measures of all three of these policies, the estimated policy effects should not be overstated due to underspecification bias. The panel includes the 48 contiguous U.S. states for the time period from 1999 through 2003. State fatality rates are measured as fatalities per million miles traveled. Measures of state policies regarding traffic safety related behavior are based on information gathered by the Insurance Institute for Highway Safety. Estimates are calculated via a time fixed effects model that uses the double-log form to allow for interaction effects between the independent variables.Results
Least squares estimates indicate that, on average, more restrictive graduated teen licensing and DUI policies significantly reduce traffic fatality rates, while stricter seat belt enforcement policies have a statistically insignificant negative impact on fatality rates. 相似文献400.
全面分析了中国西南喀斯特地区的开发潜力和制约其发展的 6个因素 ,提出了开发西南喀斯特地区的 5大战略措施 相似文献