全文获取类型
收费全文 | 622篇 |
免费 | 23篇 |
国内免费 | 43篇 |
专业分类
安全科学 | 39篇 |
废物处理 | 3篇 |
环保管理 | 175篇 |
综合类 | 270篇 |
基础理论 | 69篇 |
污染及防治 | 27篇 |
评价与监测 | 32篇 |
社会与环境 | 46篇 |
灾害及防治 | 27篇 |
出版年
2024年 | 2篇 |
2023年 | 9篇 |
2022年 | 7篇 |
2021年 | 24篇 |
2020年 | 25篇 |
2019年 | 10篇 |
2018年 | 15篇 |
2017年 | 19篇 |
2016年 | 26篇 |
2015年 | 24篇 |
2014年 | 26篇 |
2013年 | 53篇 |
2012年 | 38篇 |
2011年 | 31篇 |
2010年 | 36篇 |
2009年 | 28篇 |
2008年 | 25篇 |
2007年 | 34篇 |
2006年 | 30篇 |
2005年 | 30篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 20篇 |
2000年 | 18篇 |
1999年 | 15篇 |
1998年 | 11篇 |
1997年 | 10篇 |
1996年 | 6篇 |
1995年 | 8篇 |
1994年 | 5篇 |
1993年 | 4篇 |
1992年 | 5篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有688条查询结果,搜索用时 62 毫秒
271.
Introduced ungulates, e.g., deer and Himalayan tahr, are variously considered as both pests and resources in New Zealand. Much ecological research has occurred into these species and into the ecosystems in which they live. Concurrently, much has been done to develop ‘management’ plans for these species. We reviewed ecological research relevant to these ungulates and developed ecologically relevant criteria to assess the extent to which these have been considered in these plans. Nine criteria were developed within four thematic areas: ecological principles, objectives and outcomes, adaptive management, and use of science information. Four planning documents were then evaluated. All four poorly or at best marginally considered fundamental ecological principles: only the Himalayan thar control plan scored well in terms of having objectives and outcomes that were clearly ecologically based; the thar plan was very strong in terms of its commitment to implementing adaptive management; and, in terms of using the best available science both the thar plan and the deer issues and options paper scored well. Overall, ecological science and principles have not played major roles in the development of some of these plans, probably because ultimately they reflect political choices that are difficult to support with the available ecological research. 相似文献
272.
273.
汉江流域及丹江口库区水环境质量现状分析 总被引:12,自引:1,他引:12
江汉是南水北调中线工程的源头,文章对江汉流域丹江口库区水环境状况及中线工程动工之后可能出现的问题作了分析,提出了区域水环境的保护规划。 相似文献
274.
常州盘固水泥有限公司在新建4 500t·d-1水泥熟料生产线的同时,配套建设了低温余热发电,项目建成后,吨水泥能耗下降11%,窑头烟气粉尘削减量为2%,年增直接经济效益2 603万元,真正实现了节能减排增效的目标. 相似文献
275.
浦东新区生活垃圾焚烧厂工程实例 总被引:15,自引:1,他引:15
依据浦东新区生活垃圾产量,组分及热值等,1998年底动工兴建日处理垃圾1000t规模的焚烧厂,占地8hm^2,工程总建筑面积22197m^2,投资估算66915万元,主要焚烧设备采用SITY-2000倾斜往复阶梯式机械炉排等,配置有3条生产线,2套8500KW的化电机组。 相似文献
276.
某丝绒印染废水难生化降解,水质多变,CODcr,色度和SS分别为817-1930mg/L,229-800倍和542-1000mg/L.采用传统的生物接触氧化一气浮组合处理工艺系统,出水CODcr和色度分别在400mg/L和200位以上,远不能达国家污水排放标准,应用缺氧/二级好氧废水处理新工艺对原生化系统进行改造后,出水CODcr,色度和SS分别小于69mg/L,40倍和17mg/L.达国家太湖流 相似文献
277.
活性炭纤维吸附-催化燃烧装置处理有机废气 总被引:6,自引:1,他引:6
介绍一种处理有机废气的吸附-催化燃烧新型装置,以活性炭纤维为吸附剂,结合多单元分流组合式中附床,采用PLC电脑来实现整个系统的连续运行。实验运行结果表明,对于处理大风量,低浓度的有机废气,该技术与其他技术相比具有净化效率高,节能降耗,自动化水平高等优点。 相似文献
278.
Eggshell colour does not predict measures of maternal investment in eggs of <Emphasis Type="Italic">Turdus</Emphasis> thrushes 总被引:1,自引:0,他引:1
Cassey P Ewen JG Blackburn TM Hauber ME Vorobyev M Marshall NJ 《Die Naturwissenschaften》2008,95(8):713-721
The striking diversity of avian eggshell colour has long fascinated biologists. Recently, it has been proposed that the blue-green colour of some eggs may function as a post-mating sexually selected signal of female phenotypic quality to their mates to induce higher allocation of paternal care. It has been suggested that maternally deposited yolk carotenoids may be the specific aspect of reproductive quality that the female is signalling via eggshell colour. We use the known properties of the thrush visual system (Turdus sp.) to calculate photon capture for the four single cone photoreceptors, and the principal member of the double cone class for eggs in clutches of two introduced European thrush species (Turdus merula and Turdus philomelos) in New Zealand. We show that differences in the avian-perceived colours of individual eggs are not consistently correlated with different measures of maternal investment in the egg. Given the growing extent of the knowledge between maternal quality, parental investment and eggshell pigmentation across avian taxa, we encourage the use of avian perceptual modelling for testing alternative non-signalling explanations for the structural and physiological basis of these relationships. 相似文献
279.
The theoretical framework of a risk assessment scheme is applied to air quality assessment in a developing region in Australia, the Hunter Valley in the state of New South Wales. It is found that the application of such a scheme high-lights a number of inadequacies in the air quality management. New modeling methodologies are found to be necessary to assess some air quality impacts, as existing knowledge is inadequate. The importance of extensive data bases is underlined as is the need for social surveys to supplement air pollution monitoring when gauging aesthetic effects of air pollutants.A visiting fellow on leave from the School of Australian Environmental Studies, Griffith University, Brisbane, Queensland, Australia. 相似文献
280.
Yuping Chen Hui Yan Yijuan Yao Chunling Zeng Ping Gao Liyue Zhuang Liya Fan Daiqi Ye 《环境科学学报(英文版)》2020,32(8):1-13
Due to the influences of precursors emissions, meteorology, geography and other factors, ozone formation sensitivity (OFS) is generally spatially and temporally heterogeneous. This study characterized detailed spatial and temporal variations of OFS in Guangdong-Hong Kong-Macao Greater Bay Area (GBA) from 2012 to 2016 based on OMI satellite data, and analyzed the relationships of OFS with precursors emissions, meteorology and land use types (LUTs). From 2012 to 2016, the OFS tended to be NOx-limited in GBA, with the value of FNR (HCHO/NO2) increasing from 2.04 to 2.22. According to the total annual emission statistics of precursors, NOx emissions decreased by 33.1% and VOCs emissions increased by 35.2% from 2012 to 2016, directly resulting in OFS tending to be NOx-limited. The Grey Relation Analysis results show that total column water (TCW), surface net solar radiation (SSR), air temperature at 2 m (T2) and surface pressure (SP) are the top four meteorological factors with the greatest influences on OFS. There are significant positive correlations between FNR and T2, SSR, TCW, and significant negative correlations between FNR and SP. In GBA, the OFS tends to be NOx-limited regime in wet season (higher T2, SSR, TCW and lower SP) and VOCs-limited regime in dry season (lower T2, SSR, TCW and higher SP). The FNR displays obvious gradient variations on different LUTs, with the highest in “Rural areas”, second in “Suburban areas” and lowest in “Urban areas”. 相似文献