全文获取类型
收费全文 | 15351篇 |
免费 | 29篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 144篇 |
废物处理 | 1055篇 |
环保管理 | 1705篇 |
综合类 | 1818篇 |
基础理论 | 4466篇 |
环境理论 | 2篇 |
污染及防治 | 3148篇 |
评价与监测 | 1394篇 |
社会与环境 | 1643篇 |
灾害及防治 | 32篇 |
出版年
2023年 | 44篇 |
2022年 | 78篇 |
2021年 | 66篇 |
2020年 | 30篇 |
2019年 | 49篇 |
2018年 | 1531篇 |
2017年 | 1450篇 |
2016年 | 1302篇 |
2015年 | 195篇 |
2014年 | 171篇 |
2013年 | 478篇 |
2012年 | 624篇 |
2011年 | 1572篇 |
2010年 | 908篇 |
2009年 | 824篇 |
2008年 | 1134篇 |
2007年 | 1478篇 |
2006年 | 252篇 |
2005年 | 245篇 |
2004年 | 232篇 |
2003年 | 284篇 |
2002年 | 281篇 |
2001年 | 273篇 |
2000年 | 175篇 |
1999年 | 106篇 |
1998年 | 54篇 |
1997年 | 65篇 |
1996年 | 65篇 |
1995年 | 67篇 |
1994年 | 71篇 |
1993年 | 65篇 |
1992年 | 64篇 |
1991年 | 63篇 |
1990年 | 67篇 |
1989年 | 55篇 |
1988年 | 57篇 |
1987年 | 59篇 |
1986年 | 58篇 |
1985年 | 45篇 |
1984年 | 63篇 |
1983年 | 66篇 |
1982年 | 53篇 |
1980年 | 33篇 |
1979年 | 35篇 |
1978年 | 31篇 |
1977年 | 30篇 |
1976年 | 29篇 |
1974年 | 31篇 |
1973年 | 31篇 |
1972年 | 27篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
Aysen Müezzinoğlu Tolga Elbir Abdurrahman Bayram 《Environmental Engineering and Policy》1998,1(2):109-116
In this study, an inventory of air pollutant emission estimates from major air polluting sources in Turkey for period between 1985 and 2005 with 5-year intervals were estimated. Inventory covers anthropogenic sources of five major air pollutants of particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides and non-methane volatile organic compounds. Their break-down with respect to main activity sectors were shown and their distribution by the largest industrial source categories were worked out as annual estimates. This inventory and its analysis point to serious environmental implications of air pollutants and a need to develop a policy plan for reducing these emissions. 相似文献
132.
In several branches of science and technology a gaseous phase is dispersed into a liquid in the form of bubbles, a gaseous
component then dissolves into the liquid and subsequently undergoes chemical reaction. The overall process performance can
be improved substantially when the area of gas–liquid contact is increased. By subjecting the liquid phase to low frequency
vibrations, the bubbles are shown to suffer significant breakage, induced by resonance. When the vibration is properly tuned,
the interfacial area is found to increase by a factor of 1.8–2.4, depending on the properties of the liquid. Resonance-induced
bubble breakage phenomena have a great potential for improving the rates of chemical processes involving fast reactions, with
minimal energy input.
Received: 7 July 2000 / Accepted in revised form: 28 August 2000 相似文献
133.
Urban Flood Damage and Greenhouse Scenarios - The Implications for Policy: An Example from Australia
Urban flooding is often used as an illustration of the potentially adverse effects of greenhouse-induced climate change on extreme events. There is however, a paucity of studies that convert climate scenarios into changes in flood damage. This account summarises the use of modelling techniques, for three flood prone urban catchments in south eastern Australia, to assess changes to urban flood losses for the 'most wet' and 'most dry' scenarios for the year 2070. The most wet scenario indicates that annual average flood damage could increase within the range of 2.5 to 10 times, under the most dry scenario flood regimes would be similar to those experienced at present. The socio-economic scenarios based on the changes to flood losses are used to consider policy responses. It is unlikely that many local government authorities will respond because of lack of interest and because of major changes to the climate scenarios proposed over the last decade. Any response is likely to be incremental and accord with the 'no regrets' and the precautionary principle'. 相似文献
134.
135.
The nature of the cosmic redshift is one of the most fundamental questions in modern science. Hubble's discovery of the apparent Expansion of the Universe is derived from observations on a small number of galaxies at very low redshifts. Today, quasar redshifts have a range more than 1000 times greater than those in Hubble's sample, and represent more than 100 times as many objects. A recent comprehensive compilation of published measurements provides the basis for a study indicating that quasar observations are not in good agreement with the original predictions of the Expanding Universe theory, but are well fit by the predictions of an alternative theory having fewer adjustable parameters. 相似文献
136.
Howard Cuckle Nicholas Wald Rossana Stone James Densem James Haddow George Knight 《黑龙江环境通报》1988,8(6):439-445
Thyroid antibodies were measured in mid-trimester antenatal serum samples from 77 pregnancies affected by fetal Down's syndrome and 385 unaffected control pregnancies. Using a haemagglutination technique, thyroglobulin antibodies were detected in 5·2 per cent of cases (4) and 2·9 per cent of controls (11), and thyroid microsomal antibodies were detected in 22 per cent (17) and 15 per cent (59), respectively. Using an enzyme-linked immunosorbent assay (ELISA) for thyroglobulin antibodies and a cut-off level of 50 KIU/1, positive results were found in 25 per cent of cases (19) and 22 per cent of controls (84). Using an ELISA for thyroid microsomal antibodies and the same cut-off level, the proportions were 52 per cent (40) and 39 per cent (149), respectively. While not statistically significant, the differences were consistent with the previously reported increased levels of thyroid antibody found in nonpregnant women who had had pregnancies associated with Down's syndrome. 相似文献
137.
138.
139.
140.