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71.
In this paper, the life span of hydro and nuclear energy generations and the relationship between hydro and nuclear energy generations, environmental pollution, and economic growth were investigated for Japan covering the period of 1960–2018 by employing the Bathtub-Weibull curve and Markov switching-vector error correcting (MSVEC) method, respectively. According to the Bathtub-Weibull curve analysis, a rising failure rate for nuclear energy was found, indicating that the life of nuclear energy has expired, but a decreasing failure rate for hydroelectric energy has been detected. Then two different MSVEC models were used. The MSVEC method, unlike traditional approaches, determines the relationship between variables under different regimes. The results of MSVEC methods indicate three important points. First, regime-dependent asymmetry and regime changes are crucial for policy recommendations. Second, the shocks to hydropower and nuclear energy generations cause temporary deviations from the long-run growth path in both regimes. Lastly, the increase in hydropower generation leads to a decrease in environmental pollution and an increase in GDP, and an increase in nuclear power generation increases pollution and growth in both regimes.  相似文献   
72.
林业是重要的碳汇资源,在减缓全球气候变化、改善自然生态环境、促进经济可持续发展等方面有着至关重要的作用。作为林业碳汇的重要实现形式,碳汇造林项目兼具生态保护、促进经济发展与贫困减缓等重要功能,其实施成效究竟如何需要进一步验证。为此,本文从理论上分析了碳汇造林项目对县域经济发展的影响机理,利用2000—2016年四川47个县域的面板数据,采用PSM-DID模型估计了碳汇造林项目对县域经济发展的平均效应和动态效应,并对其影响机理进行了验证。结果显示:①碳汇造林项目的实施显著地促进了地区实际GDP和人均实际GDP的增长,这一结论在进行稳健性检验后依然成立;②囿于项目周期较长,此促进作用在短期内尚不能立竿见影,具有明显的滞后效应,且实施的时间越长,对当地经济发展的促进作用越大;③碳汇造林项目主要通过优化当地产业结构、提高居民储蓄率、提升地区政府财政收支水平等途径促进当地经济发展。因此,为更好地发挥碳汇造林项目对县域经济发展的促进作用,应继续拓展碳汇造林项目的覆盖区域,加大专项投资力度,引导碳汇造林项目向生态脆弱的深度贫困地区倾斜;在更加注重碳汇造林项目的长期效应的同时,应建立完善项目运行的长效稳定机制,防范潜在的自然与市场风险,保障项目对地区经济发展的长期驱动力;加快改善地区的融资环境,鼓励居民和企业将储蓄和融资能力有效转化为投资能力,充分依托碳汇造林项目促进当地经济可持续发展。  相似文献   
73.
Landslides are a natural hazard that presents a major threat to human life and infrastructure. Although they are a very common phenomenon in Colombia, there is a lack of analysis that entails national and comprehensive spatial, temporal, and socioeconomic evaluations of such events based on historical records. This study provides a detailed assessment of the spatial and temporal patterns and the socioeconomic impacts associated with landslides that occurred in the country between 1900 and 2018. Two national landslide databases were consulted and this information was complemented by local and regional landslide catalogues. A total of 30,730 landslides were recorded in the 118-year period. Rainfall is the most common trigger of landslides, responsible for 92 per cent of those registered, but most fatalities (68 per cent) are due to landslides caused by volcanic activity and earthquakes. An ‘fN curve’ revealed a very high frequency of small and moderate fatal landslides in the time frame.  相似文献   
74.
Rapid industrialization and urbanization in Turkey, especially over the last twenty five years, has provided better living standards to its residents, but it also caused a decrease in environmental quality. In late 1970's, air quality monitoring activities were started in some major cities by individual researchers in Turkey. It was just around the 1990's that a countrywide program on continuous air pollution monitoring in major province centers and selected large towns was launched. The impact of air pollution on people depend on various factors, such as existence and magnitude of coal powered energy generation plants, type of urban heating and their efficiency, and the numbers and specifications of vehicles. In this study, current Turkish urban air quality over the turn of the Millennium (1992–2001) is studied in the light of the country's worst cities in terms of outdoor air quality, the number of upper respiratory diseases, sinusitis, bronchitis, and pneumonia cases in these provinces reported by the state medical treatment facilities in 2001. The population that is under outdoor urban air pollution hazard was computed. A comparative analysis between the provinces that use natural gas and others that use fossil fuels was also completed in order to project monetary gains if the studied provinces will transform their indoor heating and industrial operations to be run by natural gas or other cleaner energy sources. If natural gas use in air polluted urban centers could be realized in the near future, approximately 212 to 350 million US dollars per annum could to be saved just by reducing health related problems caused by outdoor air pollution.  相似文献   
75.
首先根据安全经济开采的内涵,建立以人员安全、设施设备安全、开采环境安全、安全投资和安全管理为主要制约因素的安全经济开采评价模型,并运用改进的层次分析法确定人员可靠度对安全经济开采水平影响最大,开采环境可靠度影响最小。其次,采用函数拟合法、专家打分法、标准化打分法量化安全经济开采水平指标,并将安全经济开采水平划分为3个等级。最后,运用可拓物元模型方法,得出某铁矿安全经济开采水平为二级,无重大经济损失,与实际吻合。  相似文献   
76.
Cultural heritage does not have direct economic benefits. However, if properly managed it can stimulate social cohesions, improving the environment and have beneficial economic spin offs for the local communities. This paper discusses the role of communities in the formulation of the policies concerning their local environment. It argues that community engagement by policy makers is important in giving legitimacy and ownership of the policies. Furthermore, this paper discusses the potential of cultural heritage in diversifying the economy in Botswana. This paper recommends for the re-assessment of the relationship between the state and local communities which is critical in resuscitating the seemingly ailing community business organizations. In conclusion, it argues for the sustainable management of cultural heritage as a social and economic resource in the next 50 years of Botswana’s independence.  相似文献   
77.
The current work deals with multi-objective optimisations including financial merit factors in the multi-disciplinary conceptual design of a commercial aircraft with a specific focus on noise social cost. The results of optimisations using financial and performance-oriented objective functions have been analysed and combined in a multi-objective optimisation problem using a three-dimensional objective vector. The main novelty of the present work is the analysis of social cost noise fees effectiveness integrated in financial models embracing a wider group of stakeholders’ interests. The foundations of this research lie on the air traffic increase envisaged in the next decades and the contextual growth of the urban areas nearby airport facilities. This scenario requires the aeronautical industry to handle the environment challenge taking into account all the social and economic effects. Indeed, the consolidated technology has approached a saturation point, therefore breakthrough concepts and configurations are mandatory. This matter is addressed as a highly multi-disciplinary problem within conceptual design framework. The financial model proposed is shown to highlight the need of appropriate noise fees as instruments to push all stakeholders towards a technology radical renewal and encourage the aeronautical industry towards a shared strategy in the development of an eco-friendly commercial aviation system.  相似文献   
78.
以全国地级及以上城市中的273个样本城市为研究对象,分别从全国、沿海地区、内陆地区三个层次考察了样本城市城镇建设用地经济密度的区位差异。根据柯布-道格拉斯生产函数的理论与分析方法建立模型,分析了资本、劳动力、土地三大投入要素和城市全要素生产率等对城镇建设用地的影响,并在控制以上变量的条件下侧重考察了城市区位差异的影响。发现我国城镇建设用地经济密度的区位差异明显,具有区位优势的城市土地效益平均高于缺乏区位优势的城市;沿海水陆口岸的区位优势十分显著,建设用地经济密度相对较高,而内陆地区水陆口岸的区位优势有待发掘;航空口岸对提高城镇建设用地经济密度未发挥积极作用。分析结果表明,生产要素投入、科技水平、市场环境和城市发展阶段是影响土地效益的主要因素,但不同区位条件下城镇建设用地经济密度的影响因素有所不同,为提高城镇建设用地经济密度,不同区位条件的城市着力点应各有侧重。  相似文献   
79.
1949年以来中国环境与发展关系的演变   总被引:2,自引:0,他引:2  
从IPAT方程出发,发现了环境影响随着经济发展或时间的演变依次遵循三个"倒U型"曲线规律,即环境影响强度的倒U型曲线、人均环境影响的倒U型曲线和环境影响总量的倒U型曲线。根据此规律,可以将该演化过程划分为四个阶段即:环境影响强度高峰前阶段、环境影响强度高峰到人均环境影响量高峰阶段、人均环境影响量高峰到环境影响总量高峰阶段以及环境影响总量稳定下降阶段。在环境演变的不同阶段,主要驱动力存在着明显的差异。在环境影响强度高峰前阶段,资源消耗或污染物排放增长更多地由资源或污染密集型技术进步驱动;在资源消耗或污染物强度高峰到人均资源消耗或污染物排放高峰阶段,主要由经济增长驱动;而在人均资源消耗或污染物排放高峰到资源消耗或污染物排放总量高峰阶段以及总量高峰以后的发展阶段,则主要由节约高效技术或污染减排技术进步来驱动。实证分析表明,中国目前环境与发展关系基本上处于经济增长主要驱动的环境影响强度高峰向人均环境影响高峰过渡阶段,这同时意味着中国要在短期内实现人均环境影响和环境影响总量高峰的跨越是异常困难的。  相似文献   
80.
京津地区区域一体化程度分析   总被引:2,自引:0,他引:2  
20世纪50年代以来,全球化背景下世界各国间经济依存度加强,与之相伴生的区域集团化趋势日益显著。北京和天津作为京津冀地区经济实力最强的两个城市,两市的一体化程度研究可以在一定程度反映京津冀一体化的程度,也能对规划京津冀发展提供依据。本文从对区域经济一体化的概念和发展过程的讨论出发,并以京津地区为研究对象,从市场一体化、产业一体化和空间一体化三个方面探讨其一体化整合程度。采用"价格法",利用两市的商品零售价格指数对相对平均价格方差进行分析,得出市场较早具备了一体化的优势条件,近年来发展却不大;分析工业和第三产业各行业的区位商,了解到产业互补潜力尚未充分发挥;同时以京津冀地区的城市分布情况为研究对象,根据费里德曼空间结构的演变阶段理论将其空间一体化程度划分为初级阶段。未来通过政策引导、合理布局和整体规划,京津一体化的发展将成为区域经济发展的主要推动力之一。  相似文献   
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