首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1735篇
  免费   148篇
  国内免费   247篇
安全科学   215篇
废物处理   70篇
环保管理   340篇
综合类   921篇
基础理论   135篇
环境理论   1篇
污染及防治   95篇
评价与监测   85篇
社会与环境   251篇
灾害及防治   17篇
  2024年   9篇
  2023年   26篇
  2022年   54篇
  2021年   77篇
  2020年   80篇
  2019年   71篇
  2018年   48篇
  2017年   78篇
  2016年   87篇
  2015年   84篇
  2014年   92篇
  2013年   151篇
  2012年   146篇
  2011年   170篇
  2010年   102篇
  2009年   104篇
  2008年   76篇
  2007年   98篇
  2006年   90篇
  2005年   86篇
  2004年   50篇
  2003年   62篇
  2002年   47篇
  2001年   41篇
  2000年   29篇
  1999年   34篇
  1998年   24篇
  1997年   21篇
  1996年   20篇
  1995年   12篇
  1994年   19篇
  1993年   10篇
  1992年   6篇
  1991年   2篇
  1990年   5篇
  1989年   2篇
  1988年   2篇
  1987年   3篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1981年   1篇
  1979年   3篇
  1978年   2篇
  1973年   1篇
  1970年   1篇
排序方式: 共有2130条查询结果,搜索用时 921 毫秒
471.
工业类项目因其自身特点而成为环境监理的重点,环境监理工作主要分为设计阶段、施工阶段和试生产阶段,鉴于项目设计阶段在工业类环境监理工作中的重要作用,论述了工业类项目设计阶段环境监理的依据和要点.通过环境监理单位在实际项目设计阶段环境监理过程中发现和解决问题的案例,对工业类项目设计阶段的环境监理工作的作用进行了分析和总结.同时,对小型项目单独开展设计阶段环境监理以及环境监理工作的及早介入等提出了展望.  相似文献   
472.
采用自身对照试验,利用个体噪声剂量系统检测海洋石油钻井平台作业人员在作业期间生产性噪声个体暴露水平(40 h等效声级),采用酶联免疫吸附试验(ELISA)分别检测噪声暴露作业前后血清皮质醇水平,并分析血清皮质醇水平变化与噪声暴露水平和暴露时间的关系。结果表明:噪声暴露作业后,全部作业人员血清皮质醇水平明显升高(p0.05,α=0.05);不同噪声暴露水平作业人员血清皮质醇水平差别没有统计学意义(p0.05);噪声暴露20 d的作业人员血清皮质醇水平明显高于噪声暴露≤20 d者(p0.05)。血清皮质醇水平变化与噪声暴露水平没有显著关联性,而与噪声暴露时间呈明显的正相关(p0.05)。研究表明,生产性噪声慢性暴露使血清皮质醇水平升高,且暴露时间是主要影响因素。  相似文献   
473.
Protected areas’ chief conservation objectives are to include species within their boundaries and protect them from negative external pressures. Many protected areas are not achieving these goals, perhaps in part due to land development inside and outside protected areas. We conducted spatial analyses to evaluate the ability of Canadian protected areas to mitigate the effects of nearby land development. We investigated correlations of national patterns of land development in and around protected areas and then examined national patterns of roads, urban area, and croplands in protected areas. We calculated the amount of developed land in protected areas and within 25–100 km of protected‐area borders, the density of roads, and extent of urban and cropland area in protected areas. We constructed logistic‐regression models to test whether development in a protected area was associated with landscape and protected‐area characteristics. Land development was far less extensive inside than outside protected areas. However, several protected areas, particularly small southern areas near small urban centers had substantial development inside their boundaries, and nearly half of protected areas had roads. The cumulative extent of development within 50 km of protected areas was the best predictor of the probability of land development in protected areas. Canadian First Nations, industries, government, and nongovernmental organizations are currently planning an unprecedented number of new protected areas. Careful management of areas beyond protected‐area boundaries may prove critical to meeting their long‐term conservation objectives. Desarrollo de Tierras Dentro y Alrededor de Áreas Protegidas en la Frontera Silvestre  相似文献   
474.
发展旅游业是扩大就业的重要渠道。森林公园旅游业是中国森林旅游业的主体。本文首先概述了中国森林公园建设与发展状况,并基于林业统计年鉴数据,分析中国森林公园旅游业发展及直接就业效应,进而采用投入产出法对森林公园旅游业的间接就业效应进行了测算,最后总结全文并提出相关政策建议。研究结果表明:森林公园旅游业持续发展的就业效应可观。测算数据显示,2011-2020年森林公园旅游业的总体就业量为512.1万人,其中直接和间接就业量分别为238.5万人和273.6万人。  相似文献   
475.
Purpose. In ergonomics and human factors investigations, pulling force (PF) estimation has usually been achieved using various types of biomechanical models, and independent approximation of PF was done with the help of upper extremity joints. Recently, multiple regression methods have gained importance for task-relevant inputs in predicting PF. Artificial neural networks (ANNs) also play a vital role in fitting the data; however, their use in work-related biomechanics and ergonomics is inadequate. Therefore, the current research aimed to accomplish comparative investigation of ANN and regression models by assessing their capacity to predict PF values. Methods. Multipositional PF data were acquired from 200 subjects at three different handle heights and body locations. ANN and regression models were formed using a random sample of three subsets (75% training, 15% selection, 10% validation) for proving the outcomes. Results. The comparison of ANN and regression models shows that the predictions of ANN models had a profoundly explained variance and lower root mean square difference values for the PF data at three handle heights. Conclusions. These outcomes advise that ANNs offer a precise and robust substitute for regression methods, and should be considered a useful method in biomechanics and ergonomics task assessments.  相似文献   
476.
In industrialized countries, large amounts of mineral wastes are produced. They are re-used in various ways, particularly in road and earth constructions, substituting primary resources such as gravel. However, they may also contain pollutants, such as heavy metals, which may be leached to the groundwater. The toxic impacts of these emissions are so far often neglected within Life Cycle Assessments (LCA) of products or waste treatment services and thus, potentially large environmental impacts are currently missed. This study aims at closing this gap by assessing the ecotoxic impacts of heavy metal leaching from industrial mineral wastes in road and earth constructions. The flows of metals such as Sb, As, Pb, Cd, Cr, Cu, Mo, Ni, V and Zn originating from three typical constructions to the environment are quantified, their fate in the environment is assessed and potential ecotoxic effects evaluated. For our reference country, Germany, the industrial wastes that are applied as Granular Secondary Construction Material (GSCM) carry more than 45,000 t of diverse heavy metals per year. Depending on the material quality and construction type applied, up to 150 t of heavy metals may leach to the environment within the first 100 years after construction. Heavy metal retardation in subsoil can potentially reduce the fate to groundwater by up to 100%. One major challenge of integrating leaching from constructions into macro-scale LCA frameworks is the high variability in micro-scale technical and geographical factors, such as material qualities, construction types and soil types. In our work, we consider a broad range of parameter values in the modeling of leaching and fate. This allows distinguishing between the impacts of various road constructions, as well as sites with different soil properties. The findings of this study promote the quantitative consideration of environmental impacts of long-term leaching in Life Cycle Assessment, complementing site-specific risk assessment, for the design of waste management strategies, particularly in the construction sector.  相似文献   
477.
ABSTRACT

The large share of carbon emitted by energy-intensive industries in the extraction and processing of basic materials must be limited to decarbonise society and the economy. Ways in which the state can govern industrial decarbonisation and contributes to green state theory are explored by addressing a largely ignored issue: the green state’s industrial relations and its role in industrial governance. With insights from a Swedish case study, the tension between the state’s economic imperative and ecological concerns in greening industry are shown to persist. However, as the energy-intensive industry’s previously privileged position in the economy is weakening, industry is opened to decarbonisation strategies. While the case exposes a number of governance challenges, it also suggests potential areas where the state can pursue decarbonisation in energy-intensive industry and points the way to an active role of the green state in governing industrial decarbonisation and greening industry.  相似文献   
478.
This study involves a meta-analytical review of several articles, using the closest assumptions for the independent variable (renewable energy consumption), to determine the relationship with its environmental impacts. Furthermore, Sustainable Development Goal (SDG) in 2015 pays attention to related problems in both developing and developed countries. The effects of carbon emissions, natural resources, renewable energy consumption, and non-renewable energy on the environment are also reviewed. Following the separation of studies, the closest assumption was observed for the independent variable (energy source applications) of renewable energy. The meta-analysis was obtained using OpenMEE and JASP, and the results show the observed outcome, which was expressed in percentage. Based on the analysis, the Renewable Energy model has a value of 0.15, with the largest forest plots of 0.73, 0.69, and 0.80, recorded for studies 13, 19, and 23, respectively, while the least forest plots were recorded for studies 6, 11, 12, 15, 20, 22, 24, 25, 26, and 28. Therefore, renewable energy consumption, specifically in the mining industry, has the capacity to influence global warming. The respective industry has a unique influence on the processes that require renewable energy, for instance, the coal mining industry produces a smaller forest plot value, compared to oil and gas, or other mineral industries.  相似文献   
479.
为确保公众与化工园区之间的和谐相处,分析化工园区综合风险评价中公众参与的现状,提出公众参与实施中所应遵循的原则、方法和形式,采用社会问卷调查的形式,验证了这一工作的必要性。阐述化工园区综合风险评价中公众参与应分为三个阶段,即早期公众参与、中期公众参与及持续公众参与,针对不同时期的具体情况,指出基本的工作程序。在公众参与调查中建立评价因素集的体系框架,并采用熵权法分析评价各因素的权重,结合公众"幅值"评分,综合得出公众对于化工园区建设、规划、准入项目及正常生产时带来影响的意见和建议的倾向性。首次提出在化工园区综合风险评价中增加公众参与这一内容,有利于增加政府机构办事的透明度,同时也确保公众的利益得到足够的重视。  相似文献   
480.
哈大齐工业走廊承接产业转移水环境风险评价   总被引:1,自引:0,他引:1  
为了分析承接产业转移对水环境的影响,以哈大齐工业走廊为研究对象,在分析风险源、胁迫因子、生境、评价终点之间相互作用关系的基础上构建承接产业转移的水环境相对风险评价模型,并将研究区按照行政界线划分为3个风险评价单元,选取哈大齐地区重点承接的污染产业为风险源,选择水域作为风险受体,农田、林地、草地3种生境作为传播胁迫因子的媒介或载体,水质、水量、水生态为评价终点,对哈大齐承接产业转移水环境风险进行了定量评价.结果表明,哈尔滨市为最高风险区,其次是大庆市、齐齐哈尔市,相对风险分别为146.40、110.70和41.16.不同风险小区的最主要风险源不同,哈大齐3个城市主要风险源分别为医药制造业、化学原料与化学制品制造业及食品制造业.相反,各风险小区的主要胁迫因子大致相同,主要有需氧有机污染物、营养物质、生境破坏等.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号