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721.
将耐盐脱氮复合菌剂投加到序批式生物反应器中,构建生物强化高盐废水处理系统(SBR1),以未投加复合菌剂系统(SBR2)作为对照,分析典型周期中氮素和溶解氧的变化趋势以及盐度冲击对脱氮效果的影响.实验表明,在曝气时间为6h时,生物强化系统脱氮率可稳定在96%以上,出水总氮浓度为3.8 mg/L左右.反应中始终无硝氮、亚硝氮积累,生物强化系统具有同步硝化好氧反硝化能力.当受到5%和7%较高盐度冲击时,生物强化系统表现出优于对照系统的抗盐度冲击能力,能够快速恢复原有活性,且出水总氮低于15 mg/L;当受到0%盐度的淡水冲击时,对照系统中耐盐污泥失活且无法恢复,而生物强化系统只需投加少量(3%)耐盐脱氮复合菌剂,即可快速恢复活性,出水总氮低于15 mg/L.本研究能够为生物强化高盐废水脱氮系统的构建和运行提供技术支持. 相似文献
722.
Xi C. Wang Ming Bao Fu H. Li Hai X. Fan Han S. Li Yu Li 《Journal of environmental science and health. Part. B》2016,51(2):107-112
Fumonisin B1 (FB1) is a secondary metabolite produced by Fusarium verticillioides or Fusarium proliferatum, which present in food and feed. It causes hazardous effects on human and animal health. A monoclonal antibody (mAb) against FB1 was produced and a simple, reliable and sensitive, competitive, indirect enzyme-linked immunosorbent assay (ci-ELISA) for detection of FB1 was developed and the experiment conditions were optimized. The coating concentration of FB1-ovalbumin (FB1-OVA) was 500 ng mL?1, the action concentrations of anti-FB1 mAb and goat anti-mouse IgG were 1.28 × 104 and 1:5000, respectively. The 50% inhibitory concentration (IC50) was 11 ng mL?1, with a detectable range of 1.25–250 ng mL?1, and a limit of determination (LOD) of 1.15 ng mL?1. The cross-reactivity (CR) of the antibody against fumonisin B2 (FB2) was 60.4, and <1% against deoxynivalenol (DON), aflatoxin B1 (AFB1), ochratoxin A (OTA) or zearalenone (ZEN). In spiked samples (250 ng g?1, 500 ng g?1, 1000 ng g?1), the mean recoveries ranged from 86.7 ± 5% to 102 ± 4%, and the coefficient of variation (CV) ranged from 3% to 10%. A survey of 96 corn samples from Bozhou, Fuyang, Bengbu, and Hefei, in Anhui province, China, was performed. Frequencies of FB1 contamination were 83.3%, 95.8%, 20.8% and 91.7%, and the mean concentrations of positive samples were 0.702 μg kg?1, 0.883 μg kg?1, 0.074 μg kg?1, and 0.276 μg kg?1, respectively. The results of this study suggest that the ci-ELISA developed in this study can be used to identify FB1 in corn, furthermore, further study is needed to investigate FB1 contamination in food and feed to prevent its harmful health effects. 相似文献
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725.
基于MapInfo的矿山通风安全信息系统开发 总被引:1,自引:0,他引:1
根据现代矿山通风系统对人机交互的要求,利用OLE技术和VisualBasic编程语言,对MapInfo进行二次开发,形成了矿山通风安全信息系统。所开发的系统集成了MapInfo强大的地图、信息、数据库等的管理功能,实现了电子地图与数据库的自动连接和双向查询,完成了信息的可视化管理,并可与生产监控、调度系统集成,用于指导煤矿安全生产,防止重大事故发生。该系统具有修改通风图、生成通风管理报表、备份数据等功能,同时还可以对通风系统中的防瓦斯突出、防尘、防火、安全管理、风机等日常管理数据进行处理,在实际应用中取得了良好的效果。 相似文献
726.
Development of effective PCDD/F (polychlorinated dibenzo-p-dioxin and dibenzofuran) control technologies is essential for environmental engineers and researchers. In this study, a PCDD/F-containing gas stream generating system was developed to investigate the efficiency and effectiveness of innovative PCDD/F control technologies. The system designed and constructed can stably generate the gas stream with the PCDD/F concentration ranging from 1.0 to 100ng TEQ Nm(-3) while reproducibility test indicates that the PCDD/F recovery efficiencies are between 93% and 112%. This new PCDD/F-containing gas stream generating device is first applied in the investigation of the catalytic PCDD/F control technology. The catalytic decomposition of PCDD/Fs was evaluated with two types of commercial V(2)O(5)-WO(3)/TiO(2)-based catalysts (catalyst A and catalyst B) at controlled temperature, water vapor content, and space velocity. 84% and 91% PCDD/F destruction efficiencies are achieved with catalysts A and B, respectively, at 280 degrees C with the space velocity of 5000h(-1). The results also indicate that the presence of water vapor inhibits PCDD/F decomposition due to its competition with PCDD/F molecules for adsorption on the active vanadia sites for both catalysts. In addition, this study combined integral reaction and Mars-Van Krevelen model to calculate the activation energies of OCDD and OCDF decomposition. The activation energies of OCDD and OCDF decomposition via catalysis are calculated as 24.8kJmol(-1) and 25.2kJmol(-1), respectively. 相似文献
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728.
关于完善“大气污染防治法”的探讨 总被引:1,自引:0,他引:1
大气是人类和其他生物赖以生存和发展的基本环境要素之一。而自工业革命以来,大气受到了人类活动的影响,污染状况急剧恶化。例如著名的伦敦烟雾事件,而在中国情况也不容乐观,中国是一个在环境上回旋余地极小的大国,没有任何可能像某些先行国家那样,等到环境恶劣到极点后再来治理。但中国又是一个发展中国家,别人走过的先发展经济、再治理污染的道路,中国不可避免地也会走一遭。因此,本文通过介绍中国大气污染和大气污染立法的现状,对《大气污染防治法》存在的几点不足进行分析,并提出相应的完善建议。 相似文献
729.
为研究全氟辛烷磺酸盐(PFOS)暴露对胎鼠肺部损伤的诱导作用,孕期SD大鼠在5~20mg·kg-1剂量范围内的PFOS中处理7d,取胎鼠全肺并分析其发育所受的影响。通过形态学比较,发现随着PFOS浓度的增加,胎鼠体长和体重均显著降低,高剂量暴露会导致胎鼠死亡。通过组织学检测,发现胎鼠肺的发育受到PFOS暴露的抑制。通过WesternBlot检测肺泡Ⅰ/Ⅱ型细胞的发育,发现肺泡Ⅰ型细胞特异蛋白Podoplanin表达显著减少(p<0.05),肺泡Ⅱ型细胞特异蛋白SP-C表达减少但未出现显著差异,此外,与对照组相比高剂量暴露会引起血管内皮生长因子(VEGF)表达显著减少(p<0.01)。实验结果说明,PFOS暴露会导致胎鼠肺部发育出现损伤,这种损伤可能是肺泡Ⅰ型细胞及肺部血管发育受抑制引起胎鼠肺部气体交换功能破坏。 相似文献
730.
This study explores the current implementation challenges of the Policy Environmental Assessment (PEA), including the implementation of a far richer, more diverse (at macro level), and better understanding of PEA and integration with decision making. The results contribute to the analysis of PEA through different hierarchies of assessment. Stemming from the theory and practice of policy, a concept of PEA hierarchies is proposed including the uppermost PEA, upper-lower PEA, and lowermost PEA. Afterward, the differences of the three hierarchies are interpreted, in terms of aims, principles, processes, and methods. The evaluation of the policy environmental impacts from different lens helps solve the complexities of policies and identify opportunities for improvement of PEA. 相似文献