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731.
Goscinny S Vandevijvere S Maleki M Van Overmeire I Windal I Hanot V Blaude MN Vleminckx C Van Loco J 《Chemosphere》2011,84(3):279-288
A study was performed to assess exposure of the Belgian population to HBCD diastereoisomers. Measurements of HBCD were performed by UPLC-MS/MS, on 45 composite samples from 5 major food groups: dairy (products), meat (products), eggs, fish (products) and a group of “other” products. The medium bound estimated average daily intake (EDI) of ΣHBCD in the Belgian population was 0.99 ng kg−1 bw d−1. The diastereoisomer contribution to the mean EDI showed a predominance of γ-HBCD at 67%, followed by α-HBCD at 25% and 8% for β-HBCD. These results are consistent with the pattern found in the two food groups contributing the most to the EDI: meat (products) and the group of “other” products. Anyway, it has to be noted that diastereomeric distribution of HBCD can change due to bioisomerisation in biological material. Levels of HBCD diastereoisomers found in Belgian food samples of animal origin were low in comparison with those found in other EU countries and the resulting EDI was substantially below the proposed thresholds. 相似文献
732.
Chemical oxidation of cable insulating oil contaminated soil 总被引:2,自引:0,他引:2
Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidation leads to partial removal of highly contaminated soil, therefore chemical oxidation was investigated and optimized aiming at a subsequent bioremediation treatment. Chemical oxidation of cable oil was studied with liquid H2O2 and solid CaO2 as well as permanganate at pH 1.8, 3.0 and 7.5. Liquid H2O2 most effectively removed cable oil at pH 7.5 (24%). At pH 7.5 poor oil removal of below 5% was observed with solid CaO2 and permanganate within 2 d contact time, whereas 18% and 29% was removed at pH 1.8, respectively. A prolonged contact time of 7 d showed an increased oil removal for permanganate to 19%, such improvement was not observed for CaO2.Liquid H2O2 treatment at pH 7.5 was most effective with a low acid use and was best fit to a subsequent bioremediation treatment. To further optimize in situ chemical oxidation with subsequent bioremediation the effect of the addition of the iron catalyst and a stepwise liquid H2O2 addition was performed. Optimization led to a maximum of 46% cable oil removal with 1469 mM of H2O2, and 6.98 mM Fe(II) chelated with citric acid (H2O2:FeSO4 = 210:1 (mol mol−1). The optimum delivery method was a one step addition of the iron catalyst followed by step wise addition of H2O2. 相似文献
733.
GDP与能源消费之间的关系研究 总被引:1,自引:0,他引:1
选取中国1985-2009年能源消费总量与GDP的年度数据作为研究样本,运用Eviews对时间序列的GDP和能源消费总量进行单位根检验、协整检验、Engle-Grange因果关系检验.结果发现,GDP、能源消费总量的二阶差分在5%的显著性水平下是平稳的;GDP、能源消费总量在5%的显著性水平下,存在协整关系;Engle-Grange因果检验结果显示,在5%的显著性水平下,GDP与能源消费的因果影响关系不明显,但长期能源消费对GDP存在单向因果关系.从研究的结论来看,GDP增长引起能源需求和消费内生性的增长,减少能源的消费不影响产出、就业、收入的增长.要解决我国目前经济发展过程中诸多矛盾,使经济持续发展,首先,必须积极开发新能源、提高能源利用效率、调整能源战略、实施能源保护和节能政策来弥补我国能源短缺,提供充足的能源供给作为保障.其次,要转变经济增长方式、调整产业结构,尤其是工业结构;加快技术创新、发展高新技术产业和知识密集型产业,使我国经济发展摆脱对能源的依赖. 相似文献
734.
农村居民能源消费涉及能源安全、环境效应、新农村建设等多个方面,从发展趋势来看,在未来相当长的时期内,秸秆、薪柴等传统生物质能仍是我国农村居民的主要生活能源.本文在分析了我国农村居民可再生能源生活消费现状的基础上,测算了1998 -2007年农村居民可再生能源生活消费的碳排放,评估了农村居民可再生能源生活消费的环境效应.得出结论:在我国农村居民能源生活消费的过程中,碳排放的主体是秸秆和薪柴等生物质能的传统利用,其次是商品性能源的使用.在未来的发展过程中,农村居民能源消费必须依靠农村丰富的可再生资源,优化物质循环过程,变生物质能的传统利用为清洁利用,减少温室气体排放,实现改善农村环境,减缓和适应气候变化的总体发展目标. 相似文献
735.
736.
737.
3种典型地区农村污水排放特征调查分析 总被引:4,自引:2,他引:2
目前,我国农村污水的处理率很低,农村污染问题日益受到关注。为了深入了解我国农村污水特征,在北京、浙江和云南等地分别选择水库水源地保护区、河网地区和风景旅游区内的村庄进行农村污水排放特征的调查研究,以期为农村污水治理提供准确的基础数据。调查方法包括资料调研、入户调查和现场采样监测。结果表明,生活污水和畜禽养殖污水与粪便是村落的主要点污染源,不同区域农村用水习惯不同,污水排放规律差异较大;河网地区的村落对河浜污染状况非常严重,成为隐性污染源;旅游风景区内村庄污水特征受季节影响显著。 相似文献
738.
739.
Two surface soils contaminated with polychlorinated biphenyls (PCBs) collected from Superfund sites in the New England region of the United States, Fletcher Paints and Merrimack Industrial Metals, were evaluated for field treatment at the bench level using catalyzed H2O2 propagations (CHP—modified Fenton’s reagent). The two soils were first evaluated for the potential for in situ treatment based on two criteria: (1) temperature (<40 °C after CHP reagent addition), and (2) hydrogen peroxide longevity (>24 h). In situ CHP remediation was more applicable to the Fletcher soil, while the Merrimack soil was better suited to ex situ treatment based on temperature increases and hydrogen peroxide lifetimes. Using the highest hydrogen peroxide concentrations appropriate for in situ treatment in each soil, PCB destruction was 94% in the Fletcher soil but only 48% in the Merrimack soil. However, 98% PCB destruction was achieved in the Merrimack soil using conditions more applicable to ex situ treatment (higher hydrogen peroxide concentrations with temperatures >40 °C). Analysis of degradation products by gas chromatography/mass spectroscopy showed no detectable chlorinated degradation products, suggesting that the products of PCB oxidation were rapidly dechlorinated and degraded. The results of this research document that the two PCB-contaminated soils studied can be effectively treated using aggressive CHP conditions, and that such a detailed bench study provides important information before implementing field treatment. 相似文献
740.