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1.
我国4个大城市空气PM_(2.5)、PM_(10)污染及其化学组成   总被引:51,自引:3,他引:48  
报告了 1 995~ 1 996年在中国的广州、武汉、兰州、重庆 4大城市 8个采样点 PM2 .5 、PM2 .5~ 1 0 和 PM1 0 的监测结果。结果表明 ,1 995年 PM2 .5 年均值浓度为 57~ 1 60 μg/m3,比美国 1 997年颁布的标准值 (1 5μg/m3)高 2 .8~ 9.7倍。PM1 0 年日均值为 95~ 2 73μg/m3。除武汉市 1个对照点外 ,其余 7个监测点的 PM1 0 均超过我国空气质量二极标准 (1 0 0μg/m3)2 8%~ 1 73 % ,比美国标准 (50μg/m3)超过更多 ,说明污染是相当严重的。用 XRF分析了 PM2 .5 、PM2 .5~ 1 0 中 4 2种化学元素 ,结果表明 ,燃煤、燃油和其它工业污染的元素 As、Pb、Se、Zn、Cu、Cl、Br、S在这些颗粒物中有明显富集 ,特别是在PM2 .5 中的富集倍数达数十倍至数万倍 ,对人体健康有很大危害  相似文献
2.
We define regional sustainability as the continuous support of human quality of life within a region's ecological carrying capacity. To achieve regional sustainability, one must first assess the current situation. That is, indicators of status and progress are required. The ecological footprint is an area-based indicator which quantifies the intensity of human resource use and waste discharge activity in relation to a region's ecological carrying capacity. If the ecological footprint of a human population is greater than the area which it occupies, the population must be doing at least one of the following: receiving resources from elsewhere, disposing of some of its waste outside of the area, or depleting the area's natural capital stocks. To achieve global sustainability, the sum of all regional footprints must not exceed the total area of the biosphere. This paper explains the mechanics of a footprint calculation method for nations and regions. As the method is standardized, the relative ecological load imposed by nations and regions can be compared. Further, a nation's or region's consumption can be contrasted with its local ecological production, providing an indicator of potential vulnerability and contribution to ecological decline.  相似文献
3.
不同绿地类型在城市中的滞尘作用研究   总被引:26,自引:0,他引:26  
通过对在城市各种适宜的不同绿地类型对空气尘的阻滞作用研究,从而提供在城市绿化中不同功能区所采有各种不同绿地搭配,使之发挥出更好的作用。  相似文献
4.
突发环境事件应急处置中的监测支持   总被引:23,自引:5,他引:18       下载免费PDF全文
阐述了突发环境事件与环境应急监测的定义与分类,详细介绍了环境应急监测中事前的技术贮备、事中的处理处置及事后的评估3个环节。指出环境监测在突发环境事件的应急处置中发挥着重要的决策支持和技术保障作用。  相似文献
5.
The farming and grazing interlocked transitional zone along theGreat Wall in northern Shaanxi Province is particularly vulnerable to desertification due to its fragile ecosystem and intensive human activity. Studies reveal that desertification isboth a natural and anthropogenic process. Four desertificationindicators (vegetative cover, proportion of drifting sand area, desertification rate, and population pressure) were used to assess the severity of desertification in a GIS. The first threefactors were derived from multitemporal remote sensing and landinventory data. The last factor was calculated from census data.It was found that the overall severity of land degradation in thestudy area has worsened during the last two decades with severely, highly and moderately degraded land accounting for 84.2% of the total area in 1998. While the area affected by desertification has increased, the rate of desertification has also accelerated from 0.74 to 0.87%. Risk of land degradation in the study area has increased, on an average, by 155% since 1985. Incorporation of both natural and anthropogenic factors inthe analysis provides realistic assessment of risk of desertification.  相似文献
6.
化学物质对室内空气的污染   总被引:21,自引:0,他引:21       下载免费PDF全文
随着国内人民生活水平的提高,百姓对居室内标准的要求越来越高。装修材料含有一定的有害化学物质,可使室内不同程度地受其污染,直接影响居民的身体健康,这已引起各发达国家和国内有关部门的重视。文章主要就室内化学物质的来源、种类、污染现状和对人体健康的影响作了简要概述,同时还介绍了室内空气中化学物质的简易测试方法。  相似文献
7.
天津市臭氧污染现状与污染特征分析   总被引:21,自引:17,他引:4  
通过臭氧监测实验,系统研究了天津市城区的臭氧污染现状、污染特征和时空分布规律,并从空间上确定了城市城区易发生光化学污染的敏感区域、高发区域.  相似文献
8.
南京环境污染事故应急监测地理信息系统利用南京电子地图的地理信息,将环境污染事故应急监测数据库与GIS结合,并通过GIS技术综合分析环境污染事故中风险源要素。该系统采用支持面向对象技术的程序语言,MapObjects控件,构成面向最终用户的可执行应用程序。系统由软件平台和硬件平台组成;系统在运行环境和系统网络结构上采用客户端和服务器架构,以满足应急监测与地理信息系统相结合的目的;系统分析对GIS在环境污染应急监测中的应用作了具体分析。  相似文献
9.
Effect of fertilizer application on soil heavy metal concentration   总被引:19,自引:0,他引:19  
A large amount of chemicals is annually applied at the agricultural soils as fertilizers and pesticides. Such applications may result in the increase of heavy metals particularly Cd, Pb, and As. The objective of this study was to investigate the variability of chemical applications on Cd, Pb, and As concentrations of wheat-cultivated soils. Consequently, a study area was designed and was divided into four subareas (A, B, C, and D). The soil sampling was carried out in 40 points of cultivated durum wheat during the 2006–2007 periods. The samples were taken to the laboratory to measure their heavy metal concentration, soil texture, pH, electrical conductivity, cationic exchange capacity, organic matter, and carbonate contents. The result indicated that Cd, Pb, and As concentrations were increased in the cultivated soils due to fertilizer application. Although the statistical analysis indicates that these heavy metals increased significantly (P value < 0.05), the lead and arsenic concentrations were increased dramatically compared to Cd concentration. This can be related to overapplication of fertilizers as well as the pesticides that are used to replant plant pests, herbs, and rats.  相似文献
10.
Mathematical models are utilized to approximate various highly complex engineering, physical, environmental, social, and economic phenomena. Model parameters exerting the most influence on model results are identified through a sensitivity analysis. A comprehensive review is presented of more than a dozen sensitivity analysis methods. This review is intended for those not intimately familiar with statistics or the techniques utilized for sensitivity analysis of computer models. The most fundamental of sensitivity techniques utilizes partial differentiation whereas the simplest approach requires varying parameter values one-at-a-time. Correlation analysis is used to determine relationships between independent and dependent variables. Regression analysis provides the most comprehensive sensitivity measure and is commonly utilized to build response surfaces that approximate complex models.  相似文献
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