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831.
汽车尾气对空气的污染越来越严重,影响人们的健康生活,破坏生态环境。机动车尾气中的氮氧化物是大气污染的主要污染物之一,采取有效措施减少机动车氮氧化物排放对于空气质量的改善具有重要意义。 相似文献
832.
中国以流域为单元实行的统一区域管理虽然已普遍被世界各国政府和学者接受,但在中国并没有形成一个具有统一职权和执行效力的跨区域水环境保护管理机构。以流域水资源管理为例,流域水资源保护机构名义上受水利部与环境保护部的双重领导,但在编制上却是水利部的派出事业单位,负责具体水污染管理事宜的环境保护部门的领导权在实际中并不容易落实。同时水利部和环保部门相应的受各级地方政府领导,其财政权和人事任免权由地方政府掌控,这种地位的不独立性容易使其行为受地方政府意志的支配。另外,在晋升激励和财政分税制的制度背景下,各流域地方政府有意愿和能力干涉环保部门的行为,使各种水环境保护事物让位和屈就于更实惠的地方经济发展。对于此种跨区域水环境保护行政管理体制现存的问题应当进行改善。 相似文献
833.
Identification of optimal strategies for improving eco-resilience to floods in ecologically vulnerable regions of a wetland 总被引:4,自引:0,他引:4
In this study, a mixed integer fuzzy interval-stochastic programming model was developed for supporting the improvement of eco-resilience to floods in wetlands. This method allows uncertainties that are associated with eco-resilience improvement and can be presented as both probability distributions and interval values to be incorporated within a general modeling framework. Also, capacity-expansion plans of eco-resilience can be addressed through introducing binary variables. Moreover, penalties due to ecological damages which are associated with the violation of predefined targets can be effectively incorporated within the modeling and decision process. Thus, complexities associated with flood resistance and eco-resilience planning in wetlands can be systematically reflected, highly enhancing robustness of the modeling process. The developed method was then applied to a case of eco-resilience enhancement planning in three ecologically vulnerable regions of a wetland. Interval solutions under different river flow levels and different ecological damages were generated. They could be used for generating decision alternatives and thus help decision makers identify desired eco-resilience schemes to resist floods without causing too much damages. The application indicates that the model is helpful for supporting: (a) adjustment or justification of allocation patterns of ecological flood-resisting capacities, (b) formulation of local policies regarding eco-resilience enhancement options and policy interventions, and (c) analysis of interactions among multiple administrative targets within a wetland. 相似文献
834.
835.
There is little information on the indoor environment in hotels. Analysis of fungal DNA by quantitative PCR (qPCR) is a new method which can detect general and specific sequences. Dust was collected through swab sampling of door frames in 69 hotel rooms in 20 countries in Europe and Asia (2007-2009). Five sequences were detected by qPCR: total fungal DNA, Aspergillus and Penicillium DNA (Asp/Pen DNA), Aspergillus versicolor (A. versicolor DNA), Stachybotrys chartarum (S. chartarum DNA) and Streptomyces spp. (Streptomyces DNA). Associations were analysed by multiple linear regression. Total fungal DNA (GM = 1.08 × 10(8) cell equivalents m(-2); GSD = 6.36) and Asp/Pen DNA (GM = 1.79 × 10(7) cell equivalents m(-2); GSD = 10.12) were detected in all rooms. A. versicolor DNA, S. chartarum DNA and Streptomyces DNA were detected in 84%, 28% and 47% of the samples. In total, 20% of the rooms had observed dampness/mould, and 30% had odour. Low latitude (range 1.5-64.2 degrees) was a predictor of Asp/Pen DNA. Seaside location, lack of mechanical ventilation, and dampness or mould were other predictors of total fungal DNA and Asp/Pen DNA. Hotel ranking (Trip Advisor) or self-rated quality of the interior of the hotel room was a predictor of total fungal DNA, A. versicolor DNA and Streptomyces DNA. Odour was a predictor of S. chartarum DNA. In conclusion, fungal DNA in swab samples from hotel rooms was related to latitude, seaside location, ventilation, visible dampness and indoor mould growth. Hotels in tropical areas may have 10-100 times higher levels of common moulds such as Aspergillus and Penicillium species, as compared to a temperate climate zone. 相似文献
836.
Jun Li Aimin Li Yan Li Minhui Cai Gan Luo Yaping Wu Yechao Tian Liqun Xing Quanxing Zhang 《Frontiers of Environmental Science & Engineering》2022,16(4):47
837.
Xu Chen Liu Zaohong Cai Guanjun Zhan Jian 《Environmental science and pollution research international》2022,29(23):34278-34287
Environmental Science and Pollution Research - Due to substrate layers with different substrate configurations, extensive green roofs (EGRs) exhibit different rainfall runoff retention and... 相似文献
838.
839.
蔡小平 《防灾科技学院学报》2013,15(3):99-105
荒政是明代社会经济发展和稳定的重要保障,也是明王朝的基本国策。明代洪武永乐时期是明朝荒政的初步形成和完善时期,对整个明代都有着重要的影响。从这一时期的荒政措施中归纳出三个重要方面:一、防灾减灾措施;二、救灾赈济政策;三、灾后抚恤安民政策。这些荒政措施的实施,使明王朝从元末明初的经济凋敝、社会混乱的局面中走出来,为"洪武之治"和"永乐盛世"局面的出现奠定了基础。 相似文献
840.
Tree species and temperature change arising from seasonal variation or global warming are two important factors influencing N2O and NO emissions from forest soils. However, few studies have examined the effects of temperatures(5–35℃) on the emissions of forest soil N2O and NO in typical subtropical region. A short-term laboratory experiment was carried out to investigate the influence of temperature changes(5–35℃) on soil N2O and NO emissions under aerobic conditions in two contrasting(broad-leaved and coniferous) subtropical acidic forest types in China. The results showed that the temporal pattern of N2O and NO emissions between the three lower temperatures(5℃, 15℃, and 25℃) and 35℃ was significantly different for both broad-leaved and coniferous forest soils. The effects of temperature on soil N2O and NO emission rates varied between broad-leaved and coniferous forest soils. Both N2O and NO emissions increased exponentially with an increase in temperature in the broad-leaved forest soil. However, N2O and NO emissions in the coniferous forest soil were not sensitive to temperature change between 5℃ and 25℃. N2O and NO emission rates were significantly higher in the broad-leaved forest soil as compared with the coniferous forest soil at all incubation temperatures except 5℃. These results suggest that the broad-leaved forest could contribute more N2O and NO emissions than the coniferous forest for most of the year in the subtropical region of China. 相似文献