全文获取类型
收费全文 | 675篇 |
免费 | 10篇 |
国内免费 | 5篇 |
专业分类
安全科学 | 37篇 |
废物处理 | 31篇 |
环保管理 | 106篇 |
综合类 | 101篇 |
基础理论 | 150篇 |
污染及防治 | 182篇 |
评价与监测 | 50篇 |
社会与环境 | 27篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 12篇 |
2020年 | 3篇 |
2019年 | 8篇 |
2018年 | 12篇 |
2017年 | 21篇 |
2016年 | 15篇 |
2015年 | 23篇 |
2014年 | 25篇 |
2013年 | 50篇 |
2012年 | 25篇 |
2011年 | 42篇 |
2010年 | 28篇 |
2009年 | 31篇 |
2008年 | 36篇 |
2007年 | 44篇 |
2006年 | 40篇 |
2005年 | 30篇 |
2004年 | 23篇 |
2003年 | 24篇 |
2002年 | 24篇 |
2001年 | 10篇 |
2000年 | 20篇 |
1999年 | 8篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 8篇 |
1995年 | 10篇 |
1994年 | 9篇 |
1993年 | 14篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 9篇 |
1983年 | 7篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1961年 | 2篇 |
1959年 | 2篇 |
1957年 | 2篇 |
1953年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有690条查询结果,搜索用时 531 毫秒
121.
122.
In multiphase systems capillary pressures play a significant role on fluid movement and retention. The facility to predict
the effect of different thermal remediation strategies requires the knowledge of the effect of temperature on capillary pressure-saturation
relationships in the soils.
The objective of recent study was (a) to develop a technique for routinely measuring the pressure-saturation curves of soil
samples saturated with a nonpolar liquid at different regulated temperatures (b) to build a database using the measured pressure-saturation
curves and the physical, chemical properties of the model soils (c) to establish the dependence of nonaqueous phase liquid
retention on the soil properties and the temperature.
The retention curves (extraction isotherms) with nonaqueous phase liquid were determined using a modified
pressure plate extractor. The wetting phase was a non-aromatic hydrocarbon distillation product. Pressure plates were designed and constructed in
the laboratory of our department. The temperature was held constant at 20, 40 and 60 ∘C.
Statistical analysis was performed involving selected soil parameters and the measured nonaqueous phase liquid retention data.
The results show that knowing some easily measurable soil parameters (bulk density, particle size distribution, humus and
lime content) we can estimate the nonaqueous phase liquid retention of the soils. The measured “extraction isotherms” provide
essential information about the temperature-dependency of pressure-saturation curves. 相似文献
123.
Ewelina Wawryk-Gawda Michał K. Zarobkiewicz Katarzyna Chłapek Patrycja Chylińska-Wrzos Barbara Jodłowska-Jędrych 《毒物与环境化学》2019,101(7-8):404-419
AbstractThe use of electronic cigarettes increases as a supposedly healthier form of nicotine consumption, but safety of vaping remains uncertain. In this study, we assessed whether the use of electronic cigarettes increases the risk of infertility in male rats. Malformations of sperm morphology were more frequent in nicotine-exposed groups than in the control group. Vacuolization of seminiferous epithelium, reduction of spermatogenesis, increased apoptosis of spermatogonia and spermatocytes, and acceleration of degeneration of testes were observed. The male reproductive organs are slightly less affected by vaping than by smoking. Nevertheless, in consequence both may lead to the reduction of fertility. 相似文献
124.
Steven L. H. Teo Andre Boustany Heidi Dewar Michael J. W. Stokesbury Kevin C. Weng Shana Beemer Andrew C. Seitz Charles J. Farwell Eric D. Prince Barbara A. Block 《Marine Biology》2007,151(1):1-18
Electronic tags were used to examine the biology of Atlantic bluefin tuna (Thunnus thynnus L.) on their breeding grounds in the Gulf of Mexico (GOM). The hypothesis that movement patterns, diving behavior, and thermal
biology change during different stages of the breeding migration was tested. Mature Atlantic bluefin tuna tagged in the western
Atlantic and the GOM, were on their breeding grounds from February to June for an average of 39 ± 11 days. The bluefin tuna
experienced significantly warmer mean sea surface temperatures (SSTs) within the GOM (26.4 ± 1.6°C) than outside the GOM (20.2 ± 1.9°C).
As the bluefin tuna entered and exited the GOM, the fish dove to daily maximum depths of 568 ± 50 and 580 ± 144 m, respectively,
and exhibited directed movement paths to and from the localized breeding areas. During the putative breeding phase, the bluefin
tuna had significantly shallower daily maximum depths (203 ± 76 m), and exhibited shallow oscillatory dives during the night.
The movement paths of the bluefin tuna during the breeding phase were significantly more residential and sinuous. The heat
transfer coefficients (K) were calculated for a bluefin tuna in the GOM using the recorded ambient and body temperatures. The K for this fish increased rapidly at the high ambient temperatures encountered in the GOM, and was significantly higher at
night in the breeding phase when the fish was exhibiting shallow oscillatory dives. This suggests that the fish were behaviorally
and physiologically thermoregulating in the Gulf of Mexico. This study demonstrates that the movement patterns, diving behavior,
and thermal biology of Atlantic bluefin tuna change significantly at different stages of the breeding migration and can be
used to define spawning location and timing.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
125.
Athlua B. Attygalle Karla Jessen Hans-Jürgen Bestmann Alfred Buschinger Ulrich Maschwitz 《Chemoecology》1996,7(1):8-12
Summary Gas chromatographic analyses of volatizable material from gaster intersegmental complex glands ofP. tridentata revealed the presence of linoleic acid, palmitic acid, methyl oleate, and several long-chain hydrocarbons as major constituents, which form an oily fluid mixture. The nest relocation communication ofP. tridentata is tandem running. Tandem following is mediated by pheromones as demonstrated by dummy experiments with isolated gasters and thoraces and with glass balls. The secretions of all gaster complex glands, as well as hind gut contents and metapleural gland secretions, were unable to evoke tandem following. Morphology and position of the glands, lack of pheromonal function, oily properties, low volatility, and lack of antibiotic effects of these secretions strongly suggest a function as lubricants for the ants' gastral segments. 相似文献
126.
Barbara Demmig-Adams 《Die Naturwissenschaften》1989,76(6):262-267
Mein Dank gilt Prof. O. Björkman für einen außerordentlich anregenden und lehrreichen Aufenthalt an der Carnegie Institution in Stanford (Californien) sowie Prof. O. L. Lange, Prof. K. Winter und Prof. F.-C. Czygan für die Möglichkeit, die anschließenden Untersuchungen in Würzburg durchzuführen. Für finanzielle Unterstützung danke ich der McKnight Foundation, der Carnegie Corporation und ganz besonders der Deutschen Forschungsgemeinschaft. 相似文献
127.
128.
129.
130.