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51.
2007年11-12月国内环境事件   总被引:18,自引:18,他引:0  
简要统计了2007年11-12月国内发生的各种环境事件47起,包括沙尘天气2起,污染事件15起,地震22起,山体滑坡和泥石流6起,以及旱灾2起.对自然灾害进行了讨论.  相似文献   
52.
Interactive modes of knowledge production offer a strategy for seeking solutions to complex environmental problems. The outcome of such knowledge production is socially robust knowledge. Social robustness refers to knowledge that is relevant and accepted by actors in the context of its application. This is achieved when knowledge is credible, salient and produced in a legitimate way. To date, only limited research has focused on how social robustness is achieved. As coastal problems are characterised by conflicting interests and major uncertainties, the coastal zone represents a relevant domain for studying socially robust knowledge. This paper analyses and presents three conditions that need to be in place if one is to achieve socially robust knowledge in coastal projects. The conditions are based on theories related to socially robust knowledge, boundary spanning, project arrangements and knowledge arrangements. The conditions specify how social robustness can be achieved through knowledge testing by boundary spanners, the involvement of diverse actors and a close connection between knowledge production and the evolving project. In a case study, these conditions are compared to developments in a Dutch coastal project involving spatial developments near the Ems estuary. The comparison highlights the relevance of the three conditions in achieving socially robust knowledge. In addition, a fourth aspect is empirically uncovered: the role of boundary spanning among project partners prior to producing knowledge. These four conditions clarify how social robustness may be achieved in coastal solutions. As such, this paper contributes to the theoretical and empirical understanding of socially robust knowledge.  相似文献   
53.
简要统计了2014年11-12月国内发生的各种环境事件63起,包括沙尘天气2起,污染事件16起,地震30起,山体滑坡和泥石流6起,以及其他自然灾害9起.  相似文献   
54.
为分析当今反恐新形势下的危险品运输网络优化设计问题的研究现状,系统总结国内外关于一般场景和恐怖袭击威胁2种情况下危险品运输网络优化设计研究的主要模型和方法,梳理两者现有的研究内容,并讨论其共性及恐怖袭击威胁情景下的研究的新特点。结果发现:目前关于解决危险品运输网络优化设计问题模型的鲁棒性研究较为缺乏,尤其是模型在更为复杂和不确定性更强的恐怖袭击情景中适用性不强;危险品运输的鲁棒优化模型即使在突发事件条件下,也可以使决策者能够作出相对满意的决策;鲁棒性危险品运输网络能够规避风险扰动,可用来防止在恐怖袭击中因危险品车辆爆炸等造成更大的危害。  相似文献   
55.
以环境统计信息化管理为背景,研究了国内外信息分类与编码发展情况,系统分析了中国环境统计报告制度中统计指标的编码现状及不足,并结合工作现状及管理需求,提出了环境统计分类编码的需求,确立了环境统计分类编码的目标及原则,研究制定了以层次分类法为主、结合面分类法的环境统计分类编码方法,形成能为中国环境统计信息化管理服务的分类标准及编码体系.  相似文献   
56.
为最大程度降低溢油事故造成的不利影响,提出充分考虑海上油膜漂移特性及溢油点和漂移点对救援物资需求不确定等特点,基于鲁棒优化思想,建立救援应急成本最小、应急时间最短的双目标规划模型,并基于NSGA-Ⅱ算法设计求解方法.结果 表明:决策者可根据自身对溢油事故规模的判断,得到不同应急物资调度方案,为应急出救点的选择和物资调度...  相似文献   
57.
应用基于生理的药代动力学(PBPK)模型预测苯并(α)芘(BaP)暴露的人体内部剂量,基于贝叶斯的马尔科夫链蒙特卡洛模拟(MCMC)方法对模型参数进行校准和优化,最后运用已优化的模型对BaP内暴露基准值进行推导.研究发现,基于贝叶斯的MCMC方法对模型后验参数校准后,模型精度明显提高,两个数据集验证结果显示残差平方和分别降低了72%和94%.PBPK模型以BaP和子代谢物3-羟基苯并(α)芘(3-OHBaP)的体内动力学过程为结构基础,模拟BaP体内浓度分布大小为脂肪>肾脏>皮肤>缓慢灌注组织>快速灌注组织>静脉血>肝脏;3-OHBaP体内浓度分布大小为肾脏>快速灌注组织>脂肪>肺>静脉血>缓慢灌注组织>肝脏>皮肤.敏感性分析显示,快速灌注组织-血分配系数对模型输出影响最大,灵敏度系数超过了200%;排泄系数影响最小,只有肾小球过滤率KBR的灵敏度系数超过了1%.以美国国家环境保护局推荐的参考浓度2.0×10-6mg/m3为外暴露安全基准值,基于PBPK模型推导了职业暴露的BaP生物监测当量(BE),结果显示BE值为0.405pmol/mol肌酐(尿液3-OHBaP平均浓度),为基于人体内暴露剂量水平进行定量健康风险评估奠定了基础.  相似文献   
58.
Land managers need better techniques to assess exoticplant invasions. We used the cross-correlationstatistic, I YZ, to test for the presence ofspatial cross-correlation between pair-wisecombinations of soil characteristics, topographicvariables, plant species richness, and cover ofvascular plants in a 754 ha study site in RockyMountain National Park, Colorado, U.S.A. Using 25 largeplots (1000 m2) in five vegetation types, 8 of 12variables showed significant spatial cross-correlationwith at least one other variable, while 6 of 12variables showed significant spatial auto-correlation. Elevation and slope showed significant spatialcross-correlation with all variables except percentcover of native and exotic species. Percent cover ofnative species had significant spatialcross-correlations with soil variables, but not withexotic species. This was probably because of thepatchy distributions of vegetation types in the studyarea. At a finer resolution, using data from ten1 m2 subplots within each of the 1000 m2 plots, allvariables showed significant spatial auto- andcross-correlation. Large-plot sampling was moreaffected by topographic factors than speciesdistribution patterns, while with finer resolutionsampling, the opposite was true. However, thestatistically and biologically significant spatialcorrelation of native and exotic species could only bedetected with finer resolution sampling. We foundexotic plant species invading areas with high nativeplant richness and cover, and in fertile soils high innitrogen, silt, and clay. Spatial auto- andcross-correlation statistics, along with theintegration of remotely sensed data and geographicinformation systems, are powerful new tools forevaluating the patterns and distribution of native andexotic plant species in relation to landscape structure.  相似文献   
59.
House-Peters, Lily, Bethany Pratt, and Heejun Chang, 2010. Effects of Urban Spatial Structure, Sociodemographics, and Climate on Residential Water Consumption in Hillsboro, Oregon. Journal of the American Water Resources Association (JAWRA) 46(3):461-472. DOI: 10.1111/j.1752-1688.2009.00415.x Abstract: In the Portland metropolitan area, suburban growth in cities such as Hillsboro is projected to increase as people seek affordable housing near a burgeoning metropolis. The most significant determinants for increases in water demand are population growth, climate change, and the type of urban development that occurs. This study analyzes the spatial patterns of single family residential (SFR) water consumption in Hillsboro, Oregon, at the census block scale. The following research questions are addressed: (1) What are the significant determinants of SFR water consumption in Hillsboro, Oregon? (2) Is SFR water demand sensitive to drought conditions and interannual climate variation? (3) To what magnitude do particular census blocks react to drought conditions and interannual climate variation? Using ordinary least squares multiple regression and spatial regression methods, we found that base use, representing indoor water use, is dependent on household size and that seasonal use, representing external water use is dependent on both education level and the size of the property’s outdoor space. Spatial analysis techniques determined that although the water demand of the study area as a whole is not sensitive to drought conditions, certain individual census blocks do respond with a higher magnitude of water use. The most climate-sensitive census blocks tend to contain newer and larger homes, and have higher property values and more affluent and well-educated residents.  相似文献   
60.
ABSTRACT: Aquatic communities in the Boise River were examined from October 1987 to March 1988 to determine whether they were adversely affected by trace elements in effluents from two Boise wastewater treatment facilities. Trace-element concentrations in the Boise River were less than or near analytical-detection levels and were less than chronic toxicity criteria when detectable. Insect communities colonizing artificial substrates upstream and downstream from the wastewater treatment facilities were strongly associated, and coefficients of community loss indicated that effluents had benign enriching effects. The distributions of trace-element-intolerant mayflies indicated that trace-element concentrations in effluents did not adversely affect intolerant organisms in the Boise River. Condition factor of whitefish was significantly increased downstream from the Lander Street wastewater treatment facility and was significantly decreased downstream from the West Boise wastewater treatment facility.  相似文献   
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