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51.
吴祖强 《四川环境》1997,16(3):56-60
环境问题和环境保护已日益深入到社会政治、经济、文化、生活各个领域。在呼吁公众参与的条件下,依靠谁去搞好环境保护?公众是如何看待自己在环境保护中的作用的呢?对这些问题的回答将有助于了解公众关于环境保护的心态,有助于环境保护公众参与政策更具有针对性的实施。本文就这一话题进行了城市居民的抽样调查。调查表明,公众普遍认为,政府和公众参与是搞好环保的主要依靠力量;而公众对环境宣传教育和污染企业的治理以及技术进步的期望较低。本文进一步分析了不同年龄、文化程度、职业和人均月收入带来的影响,以期把握不同层次公众的心态。在此基础上本文就环境宣传教育如何促进公众参与提出了一些思考。  相似文献   
52.
土壤水分是土地持续利用、水资源规划与管理、环境化学、节水农业技术研究的基础。介绍了时域反射仪(TDR)及其测定土壤水分的方法及应用,并利用时域反射仪结合土钻法测定土壤容重,与经典的环刀法测定土壤容重进行了比较,结果表明:两种测定结果存在一定的差异,TDR结合土钻法测定土壤容重能连续测定而且稳定性好。  相似文献   
53.
Conservation planners need reliable information on spatial patterns of biodiversity. However, existing data sets are skewed because some ecosystems, taxa, and locations are underrepresented. We determined how many articles have been published in recent decades on the biodiversity of different countries and their constituent provinces. We searched the Web of Science catalogues Science Citation Index (SCI) and Social Science Citation Index (SSCI) for biodiversity-related articles published from 1993 to 2016 that included country and province names. We combined data on research publication frequency with other provincial-scale factors hypothesized to affect the likelihood of research activity (i.e., economic development, human presence, infrastructure, and remoteness). Areas that appeared understudied relative to the biodiversity expected based on site climate likely have been inaccessible to researchers for reasons, notably armed conflict. Geographic publication bias is of most concern in the most remote areas of sub-Saharan Africa and South America. Our provincial-scale model may help compensate for publication biases in conservation planning by revealing the spatial extent of research needs and the low cost of redoing this analysis annually.  相似文献   
54.
Abstract: The links between species–environment relations and species’ responses to protection are unclear, but the objectives of marine protected areas (MPAs) are most likely to be achieved when those relations are known and inform MPA design. The components of a species’ habitat vary with the spatial resolution of the area considered. We characterized areas at two resolutions: 250 m2 (transect) and approximately 30,000 m2 (seascape). We considered three categories of environmental variables: substrate type, bottom complexity, and depth. We sought to determine at which resolution habitat characteristics were a better predictor of abundance and species composition of fishes and whether the relations with environmental variables at either resolution affected species’ responses to protection. Habitat features accounted for a larger proportion of spatial variation in species composition and abundances than differences in protection status. This spatial variation was explained best by habitat characteristics at the seascape level than at the transect level. Species’ responses to protected areas were specific to particular seascape characteristics, primarily depth, and bottom complexity. Our method may be useful for prioritizing marine areas for protection, designing MPAs, and monitoring their effectiveness. It identified areas that provided natural shelter, areas acting as buffer zones, and areas where fish species were most responsive to protection. The identification of such areas is necessary for cost‐effective establishment and monitoring of MPAs.  相似文献   
55.
Abstract: Most protected areas are too small to sustain populations of wide‐ranging mammals; thus, identification and conservation of high‐quality habitat for those animals outside parks is often a high priority, particularly for regions where extensive land conversion is occurring. This is the case in the vicinity of Emas National Park, a small protected area in the Brazilian Cerrado. Over the last 40 years the native vegetation surrounding the park has been converted to agriculture, but the region still supports virtually all of the animals native to the area. We determined the effectiveness of scat‐detection dogs in detecting presence of five species of mammals threatened with extinction by habitat loss: maned wolf (Chrysocyon brachyurus), puma (Puma concolor), jaguar (Panthera onca), giant anteater (Myrmecophaga tridactyla), and giant armadillo (Priodontes maximus). The probability of scat detection varied among the five species and among survey quadrats of different size, but was consistent across team, season, and year. The probability of occurrence, determined from the presence of scat, in a randomly selected site within the study area ranged from 0.14 for jaguars, which occur primarily in the forested areas of the park, to 0.91 for maned wolves, the most widely distributed species in our study area. Most occurrences of giant armadillos in the park were in open grasslands, but in the agricultural matrix they tended to occur in riparian woodlands. At least one target species occurred in every survey quadrat, and giant armadillos, jaguars, and maned wolves were more likely to be present in quadrats located inside than outside the park. The effort required for detection of scats was highest for the two felids. We were able to detect the presence for each of five wide‐ranging species inside and outside the park and to assign occurrence probabilities to specific survey sites. Thus, scat dogs provide an effective survey tool for rare species even when accurate detection likelihoods are required. We believe the way we used scat‐detection dogs to determine the presence of species can be applied to the detection of other mammalian species in other ecosystems.  相似文献   
56.
对当前国内生活垃圾焚烧废气中二噁英监测相关标准和技术规范的解读和实践操作后,认识到生活垃圾焚烧废气中二噁英监测采样的现状及不足.针对不同类型烟道,不同采样时间和不同采样时间间隔分别进行了研究.实验结果表明,同一稳定气流的排放源中,水平烟道和垂直烟道测试二噁英毒性当量排放浓度水平相当;满足监测采样量要求下,不同采样时间和采样时间间隔对二噁英监测结果并无显著差异,对此给出几点相应采样建议.  相似文献   
57.
研究了珠江三角洲地区大气中多氯联苯的含量与分布.利用大气被动采样装置,共设立了包括香港在内的珠江三角洲21个大气被动采样点,样品采样时间为2005-08-15~2005-10-14.结果表明,珠三角内地的佛山(2000pg·m-3)是PCBs的高污染地区,内地采样点PCBs含量范围260~2000pg·m-3,平均值670pg·m-3.香港PCBs含量范围170~470pg·m-3,平均值300pg·m-3.香港每个采样点的PCBs含量都接近平均值,含量比较低.珠三角大气中PCBs含量与世界其它地区相比属中度污染区域.结果也表明,PUF大气被动采样器可很好地运用于区域大气PCBs污染分布与特征的对比研究.  相似文献   
58.
临安区域大气本底站CO_2浓度特征及其碳源汇变化研究   总被引:1,自引:1,他引:0  
通过分析2006年8月~2009年7月临安区域大气本底站Flask瓶采样获得的CO2浓度特征,结合碳追踪模式的模拟结果,研究了长三角地区碳源汇变化对CO2浓度的影响.结果表明,临安区域大气本底站的CO2浓度分布在368.3×10-6~414.8×10-6之间,具有较明显的季节波动变化特征,冬季高、夏季低,浓度年较差接近...  相似文献   
59.
根据国家环境质量监测网络,对“十二五”地表水环境质量监测断面调整工作要求,吉林省在辖区内所有水环境质量监测断面及采样点基础上,完成了松花江流域和辽河流域国控监测断面的优化调整工作。在此过程中,如何从国家尺度上,既能充分反映吉林省水环境质量状况,又能满足国家对地表水环境管理需求进行了深入思考。本文以吉林省为例,在确定国控监测断面及采样点的布设中.提出了自己的构想和建议。  相似文献   
60.
基于相关性分析的PCBA热力学模型修正   总被引:1,自引:0,他引:1       下载免费PDF全文
目的精确且高效地对印制电路板组件热力学模型进行修正。方法采用基于拉丁超立方抽样试验设计和Speraman等级相关系数计算公式的相关性分析方法,找出电子产品热仿真试验中对元器件表面温度值影响较大的输入参数,然后进一步分析得出输入与输出之间的函数关系。在此基础上给出印制电路板组件(PCBA)热力学模型修正的一般方法流程。最后利用该方法对某航空电子产品中一块PCBA的热力学模型进行修正。结果修正结果较精确且只调用2次有限元软件。结论该热模型修正方法具有较高的精确性和高效性,可推广用于工程实践。  相似文献   
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