全文获取类型
收费全文 | 24006篇 |
免费 | 2467篇 |
国内免费 | 7264篇 |
专业分类
安全科学 | 3914篇 |
废物处理 | 488篇 |
环保管理 | 4008篇 |
综合类 | 16446篇 |
基础理论 | 3358篇 |
环境理论 | 49篇 |
污染及防治 | 1967篇 |
评价与监测 | 1570篇 |
社会与环境 | 1325篇 |
灾害及防治 | 612篇 |
出版年
2024年 | 125篇 |
2023年 | 617篇 |
2022年 | 859篇 |
2021年 | 1040篇 |
2020年 | 1077篇 |
2019年 | 1094篇 |
2018年 | 928篇 |
2017年 | 1161篇 |
2016年 | 1259篇 |
2015年 | 1418篇 |
2014年 | 1308篇 |
2013年 | 2031篇 |
2012年 | 2116篇 |
2011年 | 2220篇 |
2010年 | 1546篇 |
2009年 | 1690篇 |
2008年 | 1316篇 |
2007年 | 1761篇 |
2006年 | 1711篇 |
2005年 | 1366篇 |
2004年 | 1126篇 |
2003年 | 1032篇 |
2002年 | 793篇 |
2001年 | 726篇 |
2000年 | 681篇 |
1999年 | 514篇 |
1998年 | 385篇 |
1997年 | 359篇 |
1996年 | 258篇 |
1995年 | 286篇 |
1994年 | 170篇 |
1993年 | 184篇 |
1992年 | 112篇 |
1991年 | 63篇 |
1990年 | 53篇 |
1989年 | 45篇 |
1988年 | 33篇 |
1987年 | 19篇 |
1986年 | 26篇 |
1985年 | 14篇 |
1984年 | 21篇 |
1983年 | 18篇 |
1982年 | 27篇 |
1981年 | 24篇 |
1980年 | 14篇 |
1979年 | 14篇 |
1978年 | 11篇 |
1973年 | 11篇 |
1972年 | 10篇 |
1971年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
131.
Ambient Air Quality Monitoring Network Design for Assessing Human Health Impacts from Exposures to Airborne Contaminants 总被引:1,自引:0,他引:1
Existing methods of establishing ambientair quality monitoring networks typically evaluateonly parameters related to ambient concentrations ofthe contaminant(s) of interest such as emissionsource characteristics, atmospheric transport anddispersion, secondary reactions, depositioncharacteristics, and local topography. However,adverse health risks from exposures to airbornecontaminants are a function of the contaminant andthe anatomic and physiologic characteristics of theexposed population. Thus, ambient air qualitymonitoring networks designed for the protection ofpublic health or for epidemiological studiesevaluating adverse health impacts from exposures toambient air contaminants should account for bothcontaminant characteristics and human healthparameters. A methodology has been establishedwhich optimizes ambient air quality monitoringnetworks for assessments of adverse human healthimpacts from exposures to airborne contaminants byincorporating human health risk assessmenttechniques. The use of risk assessment techniquesas the basis for designing ambient air qualitymonitoring networks will help to target limitedfinancial and human resources to evaluate humanhealth risks from exposures to airbornecontaminants. 相似文献
132.
Osowski SL Swick JD Carney GR Pena HB Danielson JE Parrish DA 《Environmental monitoring and assessment》2001,66(2):159-185
Swine Concentrated Animal Feeding Operations (CAFOs) have received much attention in recent years. As a result, a watershed-based screening tool, the Cumulative Risk Index Analysis (CRIA), was developed to assess the cumulative impacts of multiple CAFO facilities in a watershedsubunit. The CRIA formula calculates an index number based on: 1) the area of one or more facilities compared to the area of the watershed subunit, 2) the average of the environmental vulnerability criteria, and 3) the average of the industry-specific impact criteria. Each vulnerability or impact criterion is ranked on a 1 to 5 scale, with a low rank indicating low environmental vulnerability or impact and a high rank indicating high environmental vulnerability or impact. The individual criterion ranks, as well as the total CRIA score, can be used to focus the environmental analysis and facilitate discussions with industry, public, and other stakeholders in the Agency decision-making process. 相似文献
133.
Malcolm S. Field 《Environmental monitoring and assessment》1997,47(1):23-37
Ground-water flow and solute-transport simulation modeling are major components of most exposure and risk assessments of contaminated aquifers. Model simulations provide information on the spatial and temporal distributions of contaminants in subsurface media but are difficult to apply to karst aquifers in which conduit flow is important. Ground-water flow and solute transport in karst conduits typically display rapid-flow velocities, turbulent-flow regimes, concentrated pollutant-mass discharge, and exhibit open-channel or closed-conduit flow. Conventional ground-water models, dependent on the applicability of Darcy`s law, are inappropriate when applied to karst aquifers because of the (1) nonapplicability of Darcian-flow parameters, (2) typically nonlaminar flow regime, and (3) inability to locate the karst conduits through which most flow and contaminant transport occurs. Surface-water flow and solute-transport models conditioned on a set of parameters determined empirically from quantitative ground-water tracing studies may be effectively used to render fate-and-transport values of contaminants in karst conduits. Hydraulic-flow and geometric parameters developed in a companion paper were used in the surface-water model, TOXI5, to simulate hypothetical slug and continuous-source releases of ethylbenzene in a karst conduit. TOXI5 simulation results showed considerable improvement for predicted ethylbenzene-transport rates and concentrations over qualitative tracing and analytical ground-water model results. Ethylbenzene concentrations predicted by TOXI5 simulations were evaluated in exposure and risk assessment models. 相似文献
134.
用工业废水排放量预测地面水CODMn灰色方法研究 总被引:2,自引:0,他引:2
GPM(1)灰色生长曲线常被用于等距时序环境系统的分析建模、非等距摆动空间序列方面的应用尚未报道。本文研究提出了将非等距摆动空间序列经过等距化处理的GPM(1)线性回归优化建模方法采用该方法所建的非等距GPM(1)模型用于工业废水量预测地面水CODMn的实例表明,该方法简捷,方便、精度高于回归分析,有较大实用价值。 相似文献
135.
将有时序多目标决策方法应用于地面水环境质量优势的比较,介绍了决策方法的原理和评价步骤。实例分析表明该方法计算过程简便,分辨率高,排序结果与实际环境质量状况相符合。 相似文献
136.
博斯腾湖富营养化状态水平调查 总被引:1,自引:0,他引:1
通过水质特征和生物学特征的一个水文年规范化实地调查,采用Scirgesew参数分类标准和相关加权综合营养状态指数,对博斯腾湖水体富营养化状态水平进行了调查和评价。 相似文献
137.
运用灰色系统理论,结合实例详细介绍了GM(1,1)模型在大气环境浓度预测中的应用。 相似文献
138.
对GAM水环境预测模型提出了四点不同看法,与有关作者商榷,指出GM(1,1)模型与GAM模型二者并无优劣之差,精度亦相当。 相似文献
139.
John Boland Olena Kravchuk Wasim Saman Rowan Kilsby 《Environmental Modeling and Assessment》2003,8(2):101-113
The provision of energy for households is a major contributor to greenhouse gas emissions in the domestic sector. There is significant scope for energy savings and thus emission reduction in this sector. This paper constructs a bridge between thermal analysis and environmental assessment in the occupancy stage of the dwelling life cycle, approaching both methods as being on a common system Environment–Dwelling–Inhabitant. The importance of the local level in the thermal analysis and assessment of either a dwelling or an inhabitant's behaviour is demonstrated. It is shown that the researcher can choose between natural experiment, computer experiment and mathematical modelling to analyze the system. Such a choice is discussed for two particular methods of thermal analysis. Thermal Nomograms are the result of mathematical modelling, and the Energy Score Sheet is the result of a computer experiment in energy rating. Despite being developed for the purpose of thermal analysis, these methods can also be utilized for environmental assessment at the local level. The discussion centres on Australian conditions where the majority of the population resides in a relatively benign climate wherein behavioural alterations have significant potential for energy savings and environmental impact. The purpose of the paper is to emphasise benefits apart from energy minimisation to promote the use of energy efficient housing strategies. 相似文献
140.
分析了模糊综合评判在水质评价中的缺陷,将模糊数学中的贴近度与经典的Euclidean距离结合,提出Euclidean贴近度水质评价法。结果表明,该评价方法具有科学性、合理性,并且精度高,简单实用。 相似文献