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991.
城市绿地降低空气中含菌量的生态效应研究 总被引:24,自引:0,他引:24
按照大气生物监测的方法和要求,选择了上海市区的交通干通。公园和居住区的主要类型的绿地,对绿地降低气挟菌数量的生态效应进行了初步研究,结果表明,绿地结构,植物种类配置和粉尘污染是影响绿地降低气挟菌数量效应的主要因素。 相似文献
992.
针对DASIBI 1000系列环境空气自动监测系统中常出现的一些故障进行了分析,并提出解决的方案和建议。 相似文献
993.
Xiaodong Zou Zhemin Shen Tao Yuan Shan Yin Jingping Cai Liping Chen Wenhua Wang 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):8068-8073
In this paper, a shifted power-law model, based on the wind profile model, had been supposed to simulate concentration gradient of nitrogen dioxide (NO2) with distance from a highway. Field experiments were performed for NO2 gradients from a highway in Shanghai by using passive samplers. The shifted power-law model was fitted well with experimental results of field experiments both in this study and in the literature. The results not only verified the validity of shifted power-law relationship between NO2 concentration and the distance from a highway, but also partially demonstrated that there were some significant similarities between wind profile and air pollutants concentration profile near highway. With known concentration of chosen reference point and appropriate value of the parameter k, the model could be practically applied for predicting the NO2 distributions near a highway. The methods of determining the parameter k were also discussed for further detailed studies. 相似文献
994.
结合工作实践,归纳了目前建设项目环保设施竣工验收监测报告中存在的几个突出问题,提出了完善竣工验收监测报告的几点建议。 相似文献
995.
Schmidt S 《Environmental science and pollution research international》2003,10(3):183-187
The efficiency of a water treatment program or a water monitoring program can be checked only if it is accompanied by water analysis procedures allowing meaningful statements on water quality. Meaningful statements do not only include high accuracy, but high precision as well. With high precision values, good repeatability and reproducibility is aimed for. Repeatability and reproducibility may either be monitored by regular inter-laboratory trials, without prescribing a distinct analytical method, or by applying a standardized method which has undergone thorough checks concerning its reliability and efficiency. The article presents the structure of the ISO, CEN and DIN standardization work in water analysis. 相似文献
996.
Zdenko Franić Gina Branica Branko Petrinec Gordana Marović 《Journal of environmental science and health. Part. B》2020,55(4):382-387
AbstractThis paper presents the results of long-term investigations of 137Cs activity concentrations in chicken meat and eggs from northwest Croatia for the period 1987–2018. The research has been done as a part of monitoring program of radioactive contamination in Croatia. The highest activity concentrations in both of these foodstuffs were measured in 1987 and have been decreasing exponentially ever since. The Fukushima-Daiichi accident in 2011 did not cause any increase of 137Cs activity concentrations. The ecological half-life for 137Cs was estimated to be 8.0 and 8.4?years for chicken meat and eggs respectively. The correlation between 137Cs in fallout and chicken meat as well as between 137Cs in fallout and eggs is very good, the respective correlation coefficients being 0.79 and 0.72, indicating that fallout was the main source of 137Cs contamination in both foodstuffs. The estimated effective doses received by adult members of the Croatian population due to the intake of radiocaesium by chicken meat and egg consumption for the overall observed period are very small, 2.0 and 0.6 µSv respectively. Therefore, chicken meat and chicken egg consumption was not a critical pathway for the transfer of radiocaesium to humans. 相似文献
997.
有毒化学品销毁设施的环境保护 总被引:2,自引:0,他引:2
销毁有毒化学品时最重要的是确保人员安全与健康,以及生态环境安全。因此,其销毁活动必须遵守严格的安全与环保规定。介绍了有毒化学品销毁设施的安全与环境设计标准、控制工艺废弃物,尤其是有毒废气的具体做法,以及销毁设施内部、作业区附近的环境监测方案。这些环境保护措施同样也适用于其他有毒化学品销毁设施。 相似文献
998.
通过对仪化涤纶厂乙醛废气污染源的调查及监测,分析了其源强、生产车间及厂区内外的分布规律,并进一步作了该厂乙醛废气对环境影响的预测评价。结果表明,周边地区乙醛废气的质量浓度分布均达到《工业企业设汁卫生标准》的要求。 相似文献
999.
空气自动监测系统的仪器仪表多样化,以及数据采集装置和数据格式的差异,给系统软硬件的集成,以及数据应用和管理带来了不便,也是构成空气自动监测信息化进程中的技术瓶颈之一,通过对空气自动监测系统软件开发和数据整合模式的对比分析,探讨了解决问题的途径。 相似文献
1000.
A Decision Framework for the Adaptive Management of an Exploited Species with Implications for Marine Reserves 总被引:1,自引:0,他引:1
Abstract: Marine reserves have both conservation and fishery benefits. Nevertheless, there are no general criteria about when and where to establish new reserves, how to evaluate their efficacy, and how to conduct adaptive management to achieve conservation goals. We applied a decision-theory framework to optimally allocate conservation resources between improving data on population status and establishing a reserve for species conservation. Our goal was to maximize reserve benefits given the constraints of a population growth rate that would permit sustainability of resources. We illustrate our decision framework with a retrospective analysis of a 7-year time series on abundance of the leopard grouper ( Mycteroperca rosacea ) in the Sea of Cortés, Mexico. We used the lower bound of the distribution of the population growth rate ( λ ) as a decision rule for determining how many years of monitoring are needed to detect reserve effects. We determined the minimum time frame needed to estimate λ based on a stated level of risk tolerance for four sites. As expected, the coefficient of variation for the λ declined with the number of years of data. This increased precision with additional years of data resulted from the high degree of annual variability in the system. Where populations were slow to respond to reserves, more data were needed to detect a positive λ value. For the leopard grouper case study, confidence in the estimate of λ increased with the number of years of data. Our decision framework may be used to identify the minimum number of years of data needed before a management decision about reserve establishment could be made that is reasonably likely to meet its management objectives. 相似文献