全文获取类型
收费全文 | 237篇 |
免费 | 5篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 12篇 |
废物处理 | 14篇 |
环保管理 | 13篇 |
综合类 | 75篇 |
基础理论 | 55篇 |
污染及防治 | 55篇 |
评价与监测 | 16篇 |
社会与环境 | 5篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 11篇 |
2019年 | 5篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 12篇 |
2015年 | 16篇 |
2014年 | 11篇 |
2013年 | 16篇 |
2012年 | 16篇 |
2011年 | 13篇 |
2010年 | 12篇 |
2009年 | 10篇 |
2008年 | 15篇 |
2007年 | 20篇 |
2006年 | 13篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 11篇 |
2002年 | 7篇 |
2001年 | 2篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1978年 | 1篇 |
排序方式: 共有246条查询结果,搜索用时 15 毫秒
241.
Maeva Judith Orliac Pierre-Olivier Antoine Grégoire Métais Laurent Marivaux Jean-Yves Crochet Jean-Loup Welcomme Syed Rafiqul Hassan Baqri Ghazala Roohi 《Die Naturwissenschaften》2009,96(8):911-920
New dental remains of listriodont suids are described from the lower member of the early to middle Miocene Vihowa Formation
of the Bugti Hills, Pakistan. The material is homogeneous in terms of morphology and dimensions and referred as a whole to
Listriodon guptai Pilgrim, 1926. This species is also mentioned in coeval deposits of the Zinda Pir Dome, Pakistan, dating back to ca. 19 Ma.
The early occurrence of an advanced listriodont in Pakistan constrains the age of acquisition of several characters correlated
to lophodonty within Listriodontini, and raises major questions about the early history of the Old World Listriodontinae.
Strong morphological similarity between Listriodon guptai and the African species Listriodon akatikubas found in the late early Miocene of Maboko (Kenya, ca. 16.5 Ma) suggests that this latter is most probably a migrant originating
from Asia. 相似文献
242.
Dental microwear in relation to changes in the direction of mastication during the evolution of Myodonta (Rodentia,Mammalia) 总被引:2,自引:1,他引:1
Observations of dental microwear are used to analyse the correlation between changes in molar tooth crown morphology and the
direction of masticatory movement during the evolution of Myodonta (Rodentia, Mammalia). The studied sample includes 36 specimens
representing both superfamilies of Myodonta (Muroidea and Dipodoidea) spanning 16 dipodoid and 9 muroid species. Microscopic
scratches on occlusal surfaces resulting from contact between opposite teeth during mastication are analysed. Using these
features, we determine the direction of masticatory movements. Microwear patterns display diverse orientations among Dipodoidea:
oblique in Sicistinae, Euchoreutinae and Zapodinae, propalinal in Dipodinae and intermediary in Allactaginae. Similarly, Muroidea
exhibit the following orientations: oblique in Cricetinae and propalinal in Arvicolinae, Cricetomyinae, Gerbillinae and Murinae.
These various chewing types illustrate different evolutionary grades within the superfamilies. Acquisition of the antero-posterior
masticatory movement in Dipodoidea is related to flattening of the molar occlusal surface. However, in some muroid subfamilies,
this direction of mastication is associated with low-crowned and cuspidate molars (Cricetomyinae, Murinae). 相似文献
243.
Vigneron V Ponthieu M Barina G Audic JM Duquennoi C Mazéas L Bernet N Bouchez T 《Waste management (New York, N.Y.)》2007,27(6):778-791
Nitrified leachate recirculation has been proposed as a promising strategy for sustainable landfill management. In four test reactors, nitrate or nitrite was added (250 mg N-NO(x)(-)L(-1)) during municipal solid waste biodegradation. Nitrogen-oxides reduction reactions were monitored. Denitrification was the main nitrogen reducing reaction observed. On one hand, during the acidogenic waste degradation phase, as high amounts of volatile fatty acids (VFA) were present, nitrogen-oxides reductions were interpreted as heterotrophic denitrifications. On the other hand, denitrification reactions occurring during the late methanogenic phase were accompanied by sulphate productions and, as VFA were not detected, it was probably an autotrophic reaction. Denitrification inhibition was observed once. Ammonium concentration increased suggesting the occurrence of a dissimilatory nitrate reduction to ammonium (DNRA). Statistical treatment of analytical data revealed that only H(2)S concentration had a significant negative effect on N(2) production in our system. NO production was observed once when nitrite was injected during the acidogenic phase resulting in a total waste degradation inhibition. These results indicate that the consequences of nitrified leachate recirculation in full-scale landfills need to be carefully examined especially during the acidogenic phase or in the presence of waste containing high quantities of sulphur. 相似文献
244.
Factors affecting trace element content in periurban market garden subsoil in Yunnan Province, China 总被引:1,自引:0,他引:1
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County,Yunnan Province,South-West China.The area was divided into three different geomorphological units:specifically,mountain (M),transition (T) and lacustrine (L).Mean trace element content in subsoil were determined for Pb (58.2 mg/kg),Cd (0.89 mg/kg),Cu (129.2 mg/kg),and Zn (97.0 mg/kg).Strong significant relationships between trace element con... 相似文献
245.
The degradation of bitertanol by ozone treatment is investigated. Solutions of bitertanol (8.4 μg mL?1) were prepared either by dissolution of the standard or by dilution of Gaucho Blé seed loading solution and then ozonated under different conditions. Evolution of the concentrations of bitertanol and its ozonation by-products in both solutions was monitored by HPLC–UV as a function of the treatment time for a concentration of 100 g m?3 of ozone in the inlet gas. Bitertanol degradation was found to follow a pseudo-first order reaction in both cases. However, the rate of the reaction in diluted seed loading solution was much lower (0.19 vs. 0.27 min?1 in standard solution) and was close to the reaction rate observed in the presence of a radical scavenger, tert-butanol (0.11 min?1). Thus, it may be suggested that additives present in the seed loading solution may play the role of radical scavengers. Study of ozone concentration in the inlet gas (from 25 to 100 g m?3) showed that ozone degradation is also a first-order reaction with respect to ozone. Four ozonation by-products were highlighted, collected and identified by HPLC coupled with an ion trap mass spectrometer using positive electrospray ionization mode. A degradation pathway of bitertanol was finally proposed. 相似文献
246.
Denant-Boemont Laurent Faulin Javier Hammiche Sabrina Serrano-Hernandez Adrian 《Environmental Modeling and Assessment》2022,27(1):155-170
Environmental Modeling & Assessment - We designed a survey that aims at estimating individual willingness-to-pay to reduce noise and air pollution arising from transportation activity near the... 相似文献