全文获取类型
收费全文 | 968篇 |
免费 | 98篇 |
国内免费 | 299篇 |
专业分类
安全科学 | 111篇 |
废物处理 | 64篇 |
环保管理 | 89篇 |
综合类 | 552篇 |
基础理论 | 154篇 |
污染及防治 | 249篇 |
评价与监测 | 53篇 |
社会与环境 | 52篇 |
灾害及防治 | 41篇 |
出版年
2024年 | 4篇 |
2023年 | 29篇 |
2022年 | 68篇 |
2021年 | 59篇 |
2020年 | 48篇 |
2019年 | 40篇 |
2018年 | 55篇 |
2017年 | 52篇 |
2016年 | 43篇 |
2015年 | 58篇 |
2014年 | 80篇 |
2013年 | 102篇 |
2012年 | 74篇 |
2011年 | 79篇 |
2010年 | 68篇 |
2009年 | 77篇 |
2008年 | 45篇 |
2007年 | 50篇 |
2006年 | 42篇 |
2005年 | 44篇 |
2004年 | 30篇 |
2003年 | 28篇 |
2002年 | 30篇 |
2001年 | 26篇 |
2000年 | 26篇 |
1999年 | 16篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 9篇 |
1993年 | 7篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1365条查询结果,搜索用时 484 毫秒
881.
研究并建立了清洁地表水中的铅的氢化物发生-原子荧光光谱法.通过对样品酸度、还原剂浓度和仪器工作条件的探讨,并对标准曲线线性范围、方法检出限、精密度和准确度进行了测定.结果表明,以1.0%的硼氢化钾-1.0%铁氰化钾混合溶液为还原剂,1.0%的盐酸为载流液,标准曲线线性范围为0~50 μg/L,相关系数为0.999 9,方法检出限为0.05 μg/L,精密度为1.52%~2.79%,实际样品加标回收率为97.2%~107%.此方法灵敏度高、检出限低、操作简便、成本低廉,是一种较为理想的分析方法. 相似文献
882.
城市烂尾楼拆除有助于提升城市总体形象,但拆除后的建筑废弃物又会对城市环境造成严重的污染,为此提出一种针对烂尾楼建筑废弃物有效处理及二次利用的方法研究.基于循环经济理论及废弃物破损理论,设计了一种建筑废弃物再生利用工艺方法,利用建筑废弃物再生设备将废弃物破碎后再进行筛分处理,详尽分析了影响废弃物再生的各项工艺因素,提高废弃物再生骨料的性能,实现对烂尾楼建筑废弃物的二次有效利用.结果表明,提出的方法研究性能稳定、可靠、可以降低烂尾楼拆除成本,具有一定的推广价值. 相似文献
883.
Effect of deposit age on adsorption and desorption behaviors of ammonia nitrogen on municipal solid waste 总被引:1,自引:0,他引:1
Yan Liao Yu-Qiang Yang Dong-Sheng Shen Yu-Yang Long 《Environmental science and pollution research international》2013,20(3):1546-1555
Ammonia nitrogen pollution control is an urgent issue of landfill. This research aims to select an optimal refuse for ammonia nitrogen removal in landfill from the point of view of adsorption and desorption behavior. MSW (municipal solid waste) samples which deposit ages were in the range of 5 to 15 years (named as R15, R11, R7, and R5) were collected from real landfill site. The ammonia nitrogen adsorption behaviors of MSW including equilibrium time, adsorption isotherms, and desorption behaviors including equilibrium time were determined. Furthermore, the effects of pH, OM, Cu(II), Zn(II), and Pb(II) on adsorption and desorption behavior of ammonia nitrogen were conducted by orthogonal experiment. The equilibrium time of ammonia nitrogen adsorption by each tested MSW was very short, i.e., 20 min, whereas desorption process needed 24 h and the ammonia nitrogen released from refuses was much lesser than that adsorbed, i.e., accounted for 3.20 % (R15), 14.32 % (R11), 20.59 % (R7), and 20.50 % (R5) of each adsorption quantity, respectively. The maximum adsorption capacity estimated from Langmuir isotherm appeared in R15-KCl, i.e., 25,000 mg kg?1. The best condition for ammonia nitrogen removal from leachate was pH >7.5, OM 23.58 %, Cu(II) <5 mg L?1, Zn(II) <10 mg L?1, and Pb(II) <1 mg L?1. Ammonia nitrogen in landfill leachate could be quickly and largely absorbed by MSW but slowly and infrequently released. The refuse deposited for 15 years could be a suitable material for ammonia nitrogen removal. 相似文献
884.
Simulating Historical Variability in the Amount of Old Forests in the Oregon Coast Range 总被引:3,自引:0,他引:3
Michael C. Wimberly § Thomas A. Spies † Colin J. Long ‡ and Cathy Whitlock‡ 《Conservation biology》2000,14(1):167-180
Abstract: We developed the landscape age-class demographics simulator ( LADS) to model historical variability in the amount of old-growth and late-successional forest in the Oregon Coast Range over the past 3,000 years. The model simulated temporal and spatial patterns of forest fires along with the resulting fluctuations in the distribution of forest age classes across the landscape. Parameters describing historical fire regimes were derived from data from a number of existing dendroecological and paleoecological studies. Our results indicated that the historical age-class distribution was highly variable and that variability increased with decreasing landscape size. Simulated old-growth percentages were generally between 25% and 75% at the province scale (2,250,000 ha) and never fell below 5%. In comparison, old-growth percentages varied from 0 to 100% at the late-successional reserve scale (40,000 ha). Province-scale estimates of current old-growth (5%) and late-successional forest (11%) in the Oregon Coast Range were lower than expected under the simulated historical fire regime, even when potential errors in our parameter estimates were considered. These uncertainties do, however, limit our ability to precisely define ranges of historical variability. Our results suggest that in areas where historical disturbance regimes were characterized by large, infrequent fires, management of forest age classes based on a range of historical variability may be feasible only at relatively large spatial scales. Comprehensive landscape management strategies will need to consider other factors besides the percentage of old forests on the landscape, including the spatial pattern of stands and the rates and pathways of landscape change. 相似文献
885.
Quan-Ying Wang Dong-Mei Zhou Long Cang Lian-Zhen Li Peng Wang 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2203-2208
The aim of this study was to investigate the detailed metal speciation/fractionations of a Cu contaminated soil before and after electrokinetic remediation as well as their relationships with the soil microbial and enzyme activities. Significant changes in the exchangeable and adsorbed-Cu fractionations occurred after electrokinetic treatment, while labile soil Cu in the solution had a tendency to decrease from the anode to the cathode, and the soil free Cu2+ ions were mainly accumulated in the sections close to the cathode. The results of regression analyses revealed that both the soil Cu speciation in solution phase and the Cu fractionations in solid phase could play important roles in the changes of the soil microbial and enzyme activities. Our findings suggest that the bioavailability of soil heavy metals and their ecotoxicological effects on the soil biota before and after electroremediation can be better understood in terms of their chemical speciation and fractionations. 相似文献
886.
887.
Antimony speciation in the environment: Recent advances in understanding the biogeochemical processes and ecological effects 总被引:2,自引:0,他引:2
Mengchang He Ningning Wang Xiaojing Long Chengjun Zhang Congli M Qianyun Zhong Aihua Wang Ying Wang Aneesa Pervaiz Jun Shan 《环境科学学报(英文版)》2019,31(1):14-39
Antimony(Sb) is a toxic metalloid, and its pollution has become a global environmental problem as a result of its extensive use and corresponding Sb-mining activities. The toxicity and mobility of Sb strongly depend on its chemical speciation. In this review, we summarize the current knowledge on the biogeochemical processes(including emission, distribution,speciation, redox, metabolism and toxicity) that trigger the mobilization and transformation of Sb from pollution sources to the surrounding environment. Natural phenomena such as weathering, biological activity and volcanic activity, together with anthropogenic inputs, are responsible for the emission of Sb into the environment. Sb emitted in the environment can adsorb and undergo redox reactions on organic or inorganic environmental media, thus changing its existing form and exerting toxic effects on the ecosystem. This review is based on a careful and systematic collection of the latest papers during 2010–2017 and our research results, and it illustrates the fate and ecological effects of Sb in the environment. 相似文献
888.
含有害金属废水溶液的中和沉淀净化过程受诸多因素的影响,其中,最重要的有溶液中金属的价态和形态,溶液的离子强度,沉淀物的组成,结构和表面效应等,本文对上述问题作了较全面的理论分析。 相似文献
889.
亚硝化厌氧氨氧化生物脱氮技术 总被引:6,自引:0,他引:6
回顾了传统废水生物脱氮技术的一般原理,介绍了废水生物脱氮领域近年出现的新技术——亚硝化和厌氧氨氧化生物脱氮技术的基本原理、工艺特点及研究应用状况,展望了生物脱氮新技术的应用前景并指出了今后的研究方向。 相似文献
890.
Corinne Lampin-Maillet Marielle Jappiot Marlène Long Christophe Bouillon Denis Morge Jean-Paul Ferrier 《Journal of environmental management》2010,91(3):732-741
Every year, more than 50,000 wildland fires affect about 500,000 ha of vegetation in southern European countries, particularly in wildland-urban interfaces (WUI). This paper presents a method to characterize and map WUIs at large scales and over large areas for wildland fire prevention in the South of France. Based on the combination of four types of building configuration and three classes of vegetation structure, 12 interface types were classified. Through spatial analysis, fire ignition density and burned area ratio were linked with the different types of WUI. Among WUI types, isolated WUIs with the lowest housing density represent the highest level of fire risk. 相似文献