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571.
秦沈客运专线是我国内地第一条速度达到 2 0 0km/h的新建客运专线铁路。在技术上超越了我国现有铁路技术水平 ,因此 ,该专线的修建和管理是最具创新意义的项目 ,因此 ,在进行组织设计和施工中 ,充分利用现代化科学管理手段 ,努力实现系统安全工程。本文介绍了项目建设管理目标模式 ,讨论了安全管理过程中正确处理好的各方面关系 ,以及质量控制管理等内容  相似文献   
572.
Serious problems are faced in several parts of the world due to the presence of high concentration of fluoride in drinking water which causes dental and skeletal fluorosis to humans. Nalgonda district in Andhra Pradesh, India is one such region where high concentration of fluoride is present in groundwater. Since there are no major studies in the recent past, the present study was carried out to understand the present status of groundwater quality in Nalgonda and also to assess the possible causes for high concentration of fluoride in groundwater. Samples from 45 wells were collected once every 2 months and analyzed for fluoride concentration using an ion chromatograph. The fluoride concentration in groundwater of this region ranged from 0.1 to 8.8 mg/l with a mean of 1.3 mg/l. About 52% of the samples collected were suitable for human consumption. However, 18% of the samples were having less than the required limit of 0.6 mg/l, and 30% of the samples possessed high concentration of fluoride, i.e., above 1.5 mg/l. Weathering of rocks and evaporation of groundwater are responsible for high fluoride concentration in groundwater of this area apart from anthropogenic activities including irrigation which accelerates weathering of rocks.  相似文献   
573.
Wang  Xing  Wang  Bin  Xiao  Lili  Cui  Xiuqing  Cen  Xingzu  Yang  Shijie  Mu  Ge  Xu  Tao  Zhou  Min  Chen  Weihong 《Environmental science and pollution research international》2021,28(22):27555-27564
Environmental Science and Pollution Research - Atmospheric PM2.5-bound metals have been widely addressed, but research on the exposure levels and sources of personal PM2.5-bound metals among urban...  相似文献   
574.
为正确识别平原地区复合土地利用系统中氮磷流失敏感区,利用美国农业部水土保持局设计的水文模型中的〖WTBX〗CN〖WTBZ〗值描述地表状况,反映不同土地利用条件下下垫面对土壤氮、磷流失的影响;运用等标污染负荷计算方法评估不同类型污染源强度;建立了复合土地利用系统中土壤氮、磷流失敏感区的综合指数评价体系。构建的氮、磷流失评价方法在浙江大学华家池校区的应用评价结果表明,氮磷流失敏感性高的区块主要为研究区内的居民区、畜牧场和一些施肥量大的种植区,而敏感性最低的区块集中在具有良好植被覆盖的绿化区。高的污染源和高的迁移因子叠加区构成了高的流失敏感区.  相似文献   
575.
Li  Liubo  Li  Yanhui  Yang  Kai  Luan  Xinyu  Li  Meixiu  Cui  Mingfei  Sun  Yong  Wang  Huimin  Sun  Qinye  Tang  Kaili  Xu  Wenshuo  Zheng  Heng 《Journal of Polymers and the Environment》2021,29(6):1752-1762
Journal of Polymers and the Environment - In this study, novel composite aerogels of peach gum/activated carbon (PGAC) and peach gum/graphene oxide (PGGO) were synthesized by freeze-drying method...  相似文献   
576.
Environmental Science and Pollution Research - Dredged mud is a kind of construction material that can be reused as waste. It needs to be dehydrated before it is used. At present, plate and frame...  相似文献   
577.
578.
Tongwan City is one of the most famous and best-researched archaeological sites in China. By using palaeoclimatology proxy records from China over the last 2,000 years and archaeological/historical documents, we analyse the possible effect of climate on the collapse of Tongwan City, an ancient urban city of the Daxia state (AD 407–427). During Tongwan City’s existence (AD 413–994), two severe cold and drought stages were recorded by both natural proxy data and the synthesis compiled from the historical documents. The first cold and drought stage occurred at about AD 420–550, with the lowest point centred at about AD 500. The second cold and drought stage occurred at about AD 780–950. These periods correspond to the times of climate deterioration, especially weak summer monsoons, which eventually resulted in the intensive desertification and collapse of Tongwan City.  相似文献   
579.
•Considering evenness provides a more accurate assessment of sustainable development. •Water resource conservation drives industrial transformation. •Synergy between economic development and environmental protection is achieved. •Regional collaboration over water could promote sustainable development in drylands. Water resource availability is the major limiting factor for sustainable development in drylands. Climate change intensifies the conflicting water demands between people and the environment and highlights the importance of effective water resource management for achieving a balance between economic development and environmental protection. In 2008, Inner Mongolia, typical dryland in northern China, proposed strict regulations on water exploitation and utilization aimed at achieving sustainable development. Our study is the first to investigate the effectiveness and performance of these long-standing water conservation regulations. Our analyses found that the regulations drove industrial transformation, evidenced by the decreasing proportion of environmentally harmful industries such as coal and steel, and the increasing proportion of tertiary industries (especially tourism). Following industrial transformation, economic development decoupled from industrial water consumption and subsequently led to reduced negative environmental impacts. Based on these results, adaptive strategies were developed for 12 cities by revealing and integrating their development pathways and relative status in achieving sustainable development. Integration and cooperation between cities were proposed, e.g., a water trade agreement between eastern Inner Mongolia (an economically underdeveloped region with relatively abundant water resources) and central Inner Mongolia (an economically developed region with high water stress). Such an agreement may enable the holistic achievement of sustainable development across regions. By integrating the findings of our research, our study presents a reproducible framework for water-management-based sustainable development strategies in drylands.  相似文献   
580.
Environmental Science and Pollution Research - While intensive peach production has expanded rapidly in recent years, few studies have explored the environmental impacts associated with specific...  相似文献   
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