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201.
Carlisle in northwest England suffered its worse floods for more than 180 years in 2005. A study, reported here, was undertaken to assess the health and social impacts of these floods via in‐depth, taped individual and focus‐group interviews with people whose homes had been flooded and with agency workers who helped them. Respondents spoke of physical health ailments, psychological stress, water health‐and‐safety issues related to the floods, and disputes with insurance and construction companies, which they felt had caused and exacerbated psychological health problems. Support workers also suffered from psychological stress. Furthermore, it was found that people had low expectations of a flood and were not prepared. The findings are presented in five sections covering flood risk awareness, water contamination issues, physical health, mental health, and impact on frontline support workers. The discussion focuses on the implications of the findings for policy and practice vis‐à‐vis psychological health provision, contamination issues, training and support for frontline support workers, matters relating to restoration, and preparation for flooding.  相似文献   
202.
为探明软岩大断面隧道开挖后围岩的变形与支护时机的相关关系,利用监控测量数据反演分析中获得的蠕变参数,校正ABAQUS的D-P蠕变模型;在此基础上建立数值计算模型,对具有代表性的围岩进口浅埋段、出口浅埋段和洞身段进行了相关的数值分析,研究软岩大断面隧道岩体的变形规律和支护时机之间的关系;通过埋设现场监控量测点对二衬支护时机的结果进行了验证。研究结果表明:出口和进口浅埋段的V级围岩,开挖后岩体的变形速率大、时间短,选择以最终位移量的80%为最佳支护时机,二衬的最佳支护时机为隧道开挖支护后的15 d左右;洞身段IV级围岩具有变形速率小、时间长,以最终位移量的90%为最佳支护时机,洞身段二衬的最佳支护时机为隧道开挖支护后的30 d左右。现场验证表明,选择的二次衬砌支护的时机是可行的。  相似文献   
203.
为了揭示煤巷顶板围岩承载能力的弱化机理,结合已有的研究成果,建立巷道顶板三向承载梁结构承载弹塑流弱化分析模型,确定三向承载梁结构承载状态的分析方法,提出用围岩塑性区深度、宽度、长度作为评价巷道围岩承载的弱化分析指标,研究围岩性质、支护强度、采动应用等诱导因子对煤巷顶板结构承载能力弱化分析指标的影响规律。研究结果表明:随着围岩强度的提高、支护强度的增加、扰动应力的减小,弱化分析指标呈似线性减小的变化规律,且减幅由大到小排序为塑性区长度Sy,宽度Sx和深度Sz,同时提高围岩强度、支护强度,减小采动作用应力,煤巷顶板弱化分析指标的减小程度显著高于单因子的改善。  相似文献   
204.
Abstract

A number of tools and software systems have been developed in order to reduce the time for the design and manufacturing of industrial products. Nowadays, virtual modelling by Computer Aided Design (CAD) systems and process simulation by the application of Finite Element Method (FEM) software is a standard routine in order to compress product design activities and to achieve the optimal solution before producing any real components. These developments provided not only a reduction in the time to market but a higher complexity of the project and an improved quality of the industrial products. With the aim to further improve the sustainability of this activity, the implementation of a tool that adds automatic operations into the design activity is demonstrated. This software can interact with any CAD and helps designers when the object dimension and shape can be affected by limits and constraints deriving from different features and targets, such as the spatial collocation of the component and the interaction with other limiting items, for examples the material and the manufacturing issues. The concept was developed into the software SFIDA (Sailplane Fuselage Integrated Design Application) that is a first attempt to automatically manage multiple relations and optimise their combination.  相似文献   
205.
Claims of environmental injustice, human neglect, and racism dominated the popular and academic literature after Hurricane Katrina struck the United States in August 2005. A systematic analysis of environmental injustice from the perspective of the survivors remains scanty or nonexistent. This paper presents, therefore, a systematic empirical analysis of the key determinants of Katrina‐induced environmental injustice attitudes among survivors in severely affected parishes (counties) in Louisiana and Mississippi three years into the recovery process. Statistical models based on a random sample of survivors were estimated, with the results revealing significant predictors such as age, children in household under 18, education, homeownership, and race. The results further indicate that African‐Americans were more likely to perceive environmental injustice following Katrina than their white counterparts. Indeed, the investigation reveals that there are substantial racial gaps in measures of environmental injustice. The theoretical, methodological, and applied policy implications of these findings are discussed.  相似文献   
206.
2012 American National Election Study data supplemented with monthly temperature data from the United States Historical Climatology Network are used to examine how religion, politics, and weather and climate affect views of global warming. Evangelical fundamentalism is the most consistent factor among all religion-related variables in determining perceptions of global warming, those more oriented toward evangelical fundamentalism being less likely than others to believe in the existence, anthropogenic cause, and adverse impact of global warming. Controlling for the effects of traditional political predisposition variables, including party identification and political ideology, support for the Tea Party plays a dominant role in determining views of global warming; support for the Tea Party leading to higher likelihood of disbelief in the existence, anthropogenic cause, and negative impact of global warming. Warming winters coupled with cooling springs of the past decade are positively related with belief in the existence of global warming.  相似文献   
207.
The European Union Water Framework Directive (WFD) has created a demand for comparing the benefits and costs of the remedial measures. A major part of the benefits from improved water quality relate to the increased recreational value. However, there is a lack of easily operative and widely applicable quantitative methods to assess the benefits of improved water quality for recreational use. We present a new model to link physical indicators of water quality, water feasibility indicators for different recreational uses, individuals’ perceptions concerning the current feasibility of water for recreational purposes and monetary measures of water-related recreation benefits. The model has been applied to nine lakes, three rivers and one large coastal area in Finland. In this paper, we present the principles of the method and the results from one case study. In Finland, the method has been applied for the economic analysis required in the WFD.  相似文献   
208.
Climate change raises concern that risks of hydrological drought may be increasing. We estimate hydrological drought probabilities for rivers and streams in the United States (U.S.) using maximum likelihood logistic regression (MLLR). Streamflow data from winter months are used to estimate the chance of hydrological drought during summer months. Daily streamflow data collected from 9,144 stream gages from January 1, 1884 through January 9, 2014 provide hydrological drought streamflow probabilities for July, August, and September as functions of streamflows during October, November, December, January, and February, estimating outcomes 5‐11 months ahead of their occurrence. Few drought prediction methods exploit temporal links among streamflows. We find MLLR modeling of drought streamflow probabilities exploits the explanatory power of temporally linked water flows. MLLR models with strong correct classification rates were produced for streams throughout the U.S. One ad hoc test of correct prediction rates of September 2013 hydrological droughts exceeded 90% correct classification. Some of the best‐performing models coincide with areas of high concern including the West, the Midwest, Texas, the Southeast, and the Mid‐Atlantic. Using hydrological drought MLLR probability estimates in a water management context can inform understanding of drought streamflow conditions, provide warning of future drought conditions, and aid water management decision making.  相似文献   
209.
Economic costs, water quantity/quality benefits, and cost effectiveness of agricultural best management practices (BMPs) at a watershed scale are increasingly examined using integrated economic‐hydrologic models. However, these models are typically complex and not user‐friendly for examining the effects of various BMP scenarios. In this study, an open source geographic information system (GIS)‐based decision support system (DSS), named the watershed evaluation of BMPs (WEBs), was developed for creating BMP scenarios and simulating economic costs and water quantity/quality benefits at farm field, subbasin, and watershed scales. This DSS or WEBs interface integrated a farm economic model, the Soil and Water Assessment Tool (SWAT), and an optimization model within Whitebox Geospatial Analysis Tools (GAT), an open source GIS software. The DSS was applied to the 14.3‐km2 Gully Creek watershed, a coastal watershed in southern Ontario, Canada that drains directly into Lake Huron. BMPs that were evaluated included conservation tillage, nutrient management, cover crop, and water and sediment control basins. In addition to assessing economic costs, water quantity/quality benefits, and cost effectiveness of BMPs, the DSS can be also used to examine prioritized BMP types/locations and corresponding economic and water quantity/quality tradeoffs in the study watershed based on environmental targets or budget constraints. Further developments of the DSS including interface transfer to other watersheds are also discussed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
210.
传统锅炉承压预警技术主要依靠人工巡查发现问题,在检测过程中受工作人员自身操作不稳定因素影响,存在故障预警实时性差、盲点多等问题,达不到相应的预警要求.针对此问题,提出基于改进采用水平集算法的锅炉承压预警技术.利用图像处理技术从图像中分割出锅炉承压关键部件,统计关键部件灰度值,并利用灰度值设定特征图像及初始轮廓,设计采用...  相似文献   
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