全文获取类型
收费全文 | 544篇 |
免费 | 22篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 18篇 |
环保管理 | 123篇 |
综合类 | 35篇 |
基础理论 | 160篇 |
环境理论 | 1篇 |
污染及防治 | 165篇 |
评价与监测 | 32篇 |
社会与环境 | 14篇 |
灾害及防治 | 5篇 |
出版年
2023年 | 6篇 |
2022年 | 5篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 5篇 |
2018年 | 12篇 |
2017年 | 16篇 |
2016年 | 11篇 |
2015年 | 12篇 |
2014年 | 11篇 |
2013年 | 42篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 20篇 |
2009年 | 15篇 |
2008年 | 23篇 |
2007年 | 29篇 |
2006年 | 38篇 |
2005年 | 14篇 |
2004年 | 15篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 10篇 |
1999年 | 12篇 |
1998年 | 8篇 |
1997年 | 14篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 11篇 |
1984年 | 9篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 5篇 |
1978年 | 6篇 |
1977年 | 7篇 |
1976年 | 10篇 |
1974年 | 5篇 |
1969年 | 3篇 |
1954年 | 2篇 |
排序方式: 共有568条查询结果,搜索用时 31 毫秒
151.
Joshua A. Vance Norse B. Angus James T. Anderson 《Environmental monitoring and assessment》2013,185(9):7739-7748
Construction of man-made objects such as roads and bridges may have impacts on wildlife depending on species or location. We investigated songbirds and small mammals along the Ohio River, WV, USA at a new bridge both before and after construction and at a bridge crossing that was present throughout the study. Comparisons were made at each site over three time periods (1985–1987 [Phase I] and 1998–2000 [Phase II] [pre-construction], 2007–2009 [Phase III] [post-construction]) and at three distances (0, 100, 300 m) from the bridge or proposed bridge location. Overall, 70 songbirds and 10 small mammals were detected during the study. Cliff swallows (Petrochelidon pyrrhonota) and rock pigeons (Columba livia) showed high affinity for bridges (P?<?0.05). Combined small mammal abundances increased between Phases I and II (P?<?0.05), but did not differ between Phases II and III (P?>?0.05). Species richness and diversity for songbirds and small mammals did not differ before and after bridge construction (P?>?0.05). We found that most species sampled did not respond to the bridge crossing, and believe that the bridge is not causing any measurable negative density impacts to the species we investigated. The new bridge does provide habitat for exotic rock pigeons that are adjusted to man-made structures for nesting. 相似文献
152.
Anderson Martins de Souza Braz Antonio Rodrigues Fernandes José Roberto Ferreira Luís Reynaldo Ferracciú Alleoni 《Environmental science and pollution research international》2013,20(10):7231-7242
The solid-solution distribution or partition coefficient (Kd) is a measure of affinity of potentially toxic elements (PTE) for soil colloids. Kd plays a key role in several models for defining PTE guideline values in soils and for assessing environmental risks, and its value depends on edaphic and climatic conditions of the sites where the soils occur. This study quantified Kd values for Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn from representative soil samples from Brazil’s eastern Amazon region, which measures 1.2 million km2. The Kd values obtained were lower than those set by both international and Brazilian environmental agencies and were correlated with the pH, Fe and Mn oxide content, and cationic exchange capacity of the soils. The following order of decreasing affinity was observed: Pb?>?Cu?>?Hg?>?Cr?>?Cd?≈?Co?>?Ni?>?Zn. 相似文献
153.
Bruce J. Eckholm Kirk E. Anderson Milagra Weiss Gloria DeGrandi-Hoffman 《Behavioral ecology and sociobiology》2011,65(5):1037-1044
Multiple mating by honeybee queens results in colonies of genotypically diverse workers. Recent studies have demonstrated
that increased genetic diversity within a honeybee colony increases the variation in the frequency of tasks performed by workers.
We show that genotypically diverse colonies, each composed of 20 subfamilies, collect more pollen than do genotypically similar
colonies, each composed of a single subfamily. However, genotypically similar colonies collect greater varieties of pollen
than do genotypically diverse colonies. Further, the composition of collected pollen types is less similar among genotypically
similar colonies than among genotypically diverse colonies. The response threshold model predicts that genotypic subsets of
workers vary in their response to task stimuli. Consistent with this model, our findings suggest that genotypically diverse
colonies likely send out fewer numbers of foragers that independently search for pollen sources (scouts) in response to protein
demand by the colony, resulting in a lower variety of collected pollen types. The cooperative foraging strategy of honeybees
involves a limited number of scouts monitoring the environment that then guide the majority of foragers to high quality food
sources. The genetic composition of the colony appears to play an important role in the efficiency of this behavior. 相似文献
154.
The increasing use of ozone in water disinfection processes has been the focus of considerable concern in regards to inorganic disinfection by product formation of bromate in waters containing bromide. Due to the public health risk caused by the presence of bromate as a suspected carcinogen, attention had been addressed to the conditions under which bromate is formed. In this study, photoanodic bromine generation and bromate (BrO(3)(-)) formation were investigated using a TiO(2) electrode in a photoelectrocatalytic (PEC) treatment process. The separation of anodic and cathodic reactions in the PEC system resulted in a pH decrease from 9.3 to 3.0 in the photoanode compartment and an increase to 11.0 in the cathode compartment. Under a photo-illumination intensity of 5.7 m W cm(-2) UV, a biasing potential of +1.0V vs SCE, a pH of 6.0 and at a NaBr concentration of 1.0 x 10(-2) M, active bromine formation increased over time with 2.4 x 10(-6) M min(-6) rate and reached a steady-state concentration of 1.44 x 10(-4) M in 60 min. Bromate formation was detected after a lag-period of 15 min and exhibited a continuous increasing trend with respect to irradiation time. No bromate formation was observed below pH 6.5 whereas an increasing bromate concentrations and pH up to pH=8.5 were noted. 相似文献
155.
156.
157.
158.
159.
160.
Performance of a combined anaerobic reactor for municipal wastewater treatment at ambient temperature 总被引:1,自引:0,他引:1
A bench-scale experimental study was carried out to investigate the overall performance of a combined anaerobic reactor for treating pre-settled municipal wastewater at ambient temperature (18–28°C) in terms of substrate removal efficiencies, biogas, methane production, volatile fatty acid (VFA) profiles and effluent suspended solids (SS) concentration, etc. The tested reactor was a modified anaerobic baffled reactor (ABR). The second and third compartments were partly packed with supporting media. The experimental results were similar to, or compared favourably with, other anaerobic reactor systems for municipal wastewater treatment at ambient temperature and proved the technical feasibility of this compartmentalised reactor. Considering its simple structure and operation, it could be considered a potential reactor system for treating municipal and domestic wastewaters in tropical and sub-tropical areas of developing countries. 相似文献