全文获取类型
收费全文 | 163篇 |
免费 | 1篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 3篇 |
环保管理 | 25篇 |
综合类 | 33篇 |
基础理论 | 43篇 |
污染及防治 | 36篇 |
评价与监测 | 8篇 |
社会与环境 | 7篇 |
灾害及防治 | 2篇 |
出版年
2023年 | 4篇 |
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 3篇 |
2018年 | 2篇 |
2017年 | 3篇 |
2016年 | 12篇 |
2015年 | 7篇 |
2014年 | 8篇 |
2013年 | 19篇 |
2012年 | 8篇 |
2011年 | 12篇 |
2010年 | 7篇 |
2009年 | 10篇 |
2008年 | 12篇 |
2007年 | 6篇 |
2006年 | 8篇 |
2005年 | 7篇 |
2004年 | 7篇 |
2002年 | 2篇 |
2001年 | 2篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1981年 | 2篇 |
1958年 | 1篇 |
排序方式: 共有168条查询结果,搜索用时 31 毫秒
11.
注浆法治理公路黄土暗穴病害的试验研究 总被引:1,自引:1,他引:0
注浆法是公路工程中治理暗穴的一种新方法.针对湿陷性黄土地区公路工程中大量发育的暗穴病害,通过室内浆液材料物理力学性能试验与工程现场模拟注浆效果试验,分析了以水泥为主剂的注浆材料在不同配合比情况下治理公路工程中暗穴的效果.室内外试验结果分析表明:浆液水灰比在2.5∶1~1.5∶1之间较为适宜;在不影响路基路面的正常压力下有效的加固半径是1.0 m~1.5 m;在特殊情况下为了使浆液快速凝结可以加入一定量的水玻璃作为速凝剂;可以采用二次注浆加强治理的效果. 相似文献
12.
Nina Y. Ileva Hideaki Shibata Fuyuki Satoh Kaichiro Sasa Hiroshi Ueda 《Sustainability Science》2009,4(2):189-198
The present research investigated the relationship between nitrate–nitrogen (NO3–N) in river water and the land use/land cover (hereafter, land use) in the Teshio River watershed located in northern Hokkaido
island to understand the effect of human activities such as agriculture, forestry, industry, and urbanization in the drainage
basin on the river ecosystem quality and services. River water was sampled at nine points seasonally during a 2-year period
and the nutrients concentration was measured. Land use profiles were estimated at two spatial scales, riparian and sub-catchment,
for each sampling station. The spatial pattern of water quality in the Teshio River showed increased NO3–N levels associated with agriculture and urban expansion, and forest reduction in the watershed. Land use at the riparian
scale closely reflected that at the sub-catchment scale, which masked the unique riparian buffer effect on the river water
condition. The increased agricultural and reduced forest area in the riparian zone, especially in the upper middle reach,
could be a possible reason for a decline of ecosystem service for the provisioning of clean water and habitat for aquatic
organisms. Measures towards sustainable and more nature-friendly agricultural management are necessary in the area to protect
the Teshio River ecosystem and its ecosystem services. 相似文献
13.
Franck L. B. Meijboom Nina Cohen Elsbeth N. Stassen Frans W. A. Brom 《Journal of Agricultural and Environmental Ethics》2009,22(6):559-571
European animal disease policy seems to find its justification in a “harm to other” principle. Limiting the freedom of animal
keepers—e.g., by culling their animals—is justified by the aim to prevent harm, i.e., the spreading of the disease. The picture,
however, is more complicated. Both during the control of outbreaks and in the prevention of notifiable, animal diseases the
government is confronted with conflicting claims of stakeholders who anticipate running a risk to be harmed by each other, and who ask for government intervention. In this paper, we first argue that in a policy that
aims to prevent animal diseases, the focus shifts from limiting “harm” to weighing conflicting claims with respect to “risks
of harm.” Therefore, we claim that the harm principle is no longer a sufficient justification for governmental intervention
in animal disease prevention. A policy that has to deal with and distribute conflicting risks of harm needs additional value
assumptions that guide this process of assessment and distribution. We show that currently, policies are based on assumptions
that are mainly economic considerations. In order to show the limitations of these considerations, we use the interests and
position of keepers of backyard animals as an example. Based on the problems they faced during and after the recent outbreaks,
we defend the thesis that in order to develop a sustainable animal disease policy other than economic assumptions need to
be taken into account. 相似文献
14.
Nina E. Cohen Frans W. A. Brom Elsbeth N. Stassen 《Journal of Agricultural and Environmental Ethics》2009,22(4):341-359
In this paper, we present and defend the theoretical framework of an empirical model to describe people’s fundamental moral
attitudes (FMAs) to animals, the stratification of FMAs in society and the role of FMAs in judgment on the culling of healthy
animals in an animal disease epidemic. We used philosophical animal ethics theories to understand the moral basis of FMA convictions.
Moreover, these theories provide us with a moral language for communication between animal ethics, FMAs, and public debates.
We defend that FMA is a two-layered concept. The first layer consists of deeply felt convictions about animals. The second
layer consists of convictions derived from the first layer to serve as arguments in a debate on animal issues. In a debate,
the latter convictions are variable, depending on the animal issue in a specific context, time, and place. This variability
facilitates finding common ground in an animal issue between actors with opposing convictions. 相似文献
15.
The antimicrobial activity of Cu2O, ZnO and NiO nanoparticles supported onto natural clinoptilolite was investigated in the secondary effluent under dark conditions. After 24 h of contact the Cu2O and ZnO nanoparticles reduced the numbers of viable bacterial cells of Escherichia coli and Staphylococcus aureus in pure culture for four to six orders of magnitude and showed consistent 100% of antibacterial activity against native E. coli after 1 h of contact during 48 exposures. The antibacterial activity of NiO nanoparticles was less efficient. The Cu2O and NiO nanoparticles showed 100% of antiprotozoan activity against Paramecium caudatum and Euplotes affinis after 1 h of contact, while ZnO nanoparticles were less efficient. The morphology and crystallinity of the nanoparticles were not affected by microorganisms. The metal oxide nanoparticles could find a novel application in the disinfection of secondary effluent and removal of pathogenic microorganisms in the tertiary stage of wastewater treatment. 相似文献
16.
Effects of riparian forest buffers on in-stream nutrient retention in agricultural catchments 总被引:6,自引:0,他引:6
Weigelhofer G Fuchsberger J Teufl B Welti N Hein T 《Journal of environmental quality》2012,41(2):373-379
In northeastern Austria, marshlands have been turned into the most productive arable land of the country. As a result, most headwater streams show structurally degraded channels, lacking riparian buffer zones, which are heavily loaded with nutrients from the surrounding crop fields. The present study examines whether longitudinally restricted riparian forest buffers can enhance the in-stream nutrient retention in nutrient-enriched headwater streams. We estimated nutrient uptake from pairwise, short-term addition experiments with NH, NH, PO, and NaCl within reaches with riparian forest buffers (RFB) and degraded reaches (DEG) of the same streams. Riparian forest buffers originated from the conservation of the pristine vegetation or from restoration measures. Hydrologic retention was calculated with the model OTIS-P on the basis of conductivity break-through curves from the salt injections. A significant increase in surface transient storage was revealed in pristine and restored RFB reaches compared with DEG reaches due to the longitudinal step-pool pattern and the frequent occurrence of woody debris on the channel bed. Ammonium uptake lengths were significantly shorter in RFB reaches than in DEG reaches, resulting from the higher hydrologic retention. Uptake velocities did not differ significantly between RFB and DEG reaches, indicating that riparian forest buffers did not affect the biochemical nutrient demand. Uptake of NH was mainly driven by autotrophs. Net PO uptake was not affected by riparian forest buffers. The study shows that the physical and biogeochemical effects of riparian forest buffers on the in-stream nutrient retention are limited in the case of highly eutrophic streams. 相似文献
17.
Troldborg M Lemming G Binning PJ Tuxen N Bjerg PL 《Journal of contaminant hydrology》2008,101(1-4):14-28
Contaminated sites pose a significant threat to groundwater resources worldwide. Due to limited available resources a risk-based prioritisation of the remediation efforts is essential. Existing risk assessment tools are unsuitable for this purpose, because they consider each contaminated site separately and on a local scale, which makes it difficult to compare the impact from different sites. Hence a modelling tool for risk assessment of contaminated sites on the catchment scale has been developed. The CatchRisk screening tool evaluates the risk associated with each site in terms of its ability to contaminate abstracted groundwater in the catchment. The tool considers both the local scale and the catchment scale. At the local scale, a flexible, site specific leaching model that can be adjusted to the actual data availability is used to estimate the mass flux over time from identified sites. At the catchment scale, a transport model that utilises the source flux and a groundwater model covering the catchment is used to estimate the transient impact on the supply well. The CatchRisk model was tested on a groundwater catchment for a waterworks north of Copenhagen, Denmark. Even though data scarcity limited the application of the model, the sites that most likely caused the observed contamination at the waterworks were identified. The method was found to be valuable as a basis for prioritising point sources according to their impact on groundwater quality. The tool can also be used as a framework for testing hypotheses on the origin of contamination in the catchment and for identification of unknown contaminant sources. 相似文献
18.
One of the major consequences of global warming is a rise in sea surface temperature which may affect the survival of marine
organisms including phytoplankton. Here, we provide experimental evidence for heat-induced cell death in a symbiotic microalga.
Shifting Symbiodinium microadriaticum from 27 to 32°C resulted in an increase in mortality, an increase in caspase 3-like activity, and an increase in nitric oxide
(NO) production. The caspase-like activity was strongly correlated with the production of NO in thermally challenged microalgae.
For this experiment, the application of Ac-DEVD-CHO, a mammalian caspase 3-specific inhibitor, partly prevented (by 65%) the
increase in caspase-like activity. To verify the relationship between NO and the caspase-like activity, S. microadriaticum were subsequently incubated with 1.0 mM of the following chemical NO donors: sodium nitroprusside (SNP), S-nitrosoglutathione (GSNO), S-nitroso-N-acetylpenicillamine (SNAP) and 3,3bis(Aminoethyl)-1-hydroxy-2-oxo-1-triazene (NOC-18). The supplementation of both SNP and
NOC-18 caused a significant increase in caspase-like activity compared to the control treatment. Pre-treatment of the microalgae
with the inhibitor Ac-DEVD-CHO before the supplementation of the different NO donors completely prevented the increase in
caspase-like activity. These results suggest that NO could play a role in the induction of cell death in heat-stressed S. microadriaticum by mediating an increase in caspase-like activity. 相似文献
19.
Nina Peuhkuri 《Behavioral ecology and sociobiology》1998,43(4-5):333-337
Individuals which deviate from the majority in groups are likely to be most vulnerable to predation. This oddity effect,
by definition, is frequency dependent, eventually fading at equal frequencies of the phenotypes in a group. It has been hypothesized
that the increased predation risk of odd individuals may play an important role in the formation of phenotypically uniform
shoals of fish. However, recent work has indicated that individuals may experience, or value, their predation hazard differently
depending on their own size in relation to that of other group members: single large fish, but not small ones, appear concerned
about their oddity in a shoal. Here I show that the apparent wariness of large fish is also expressed in a frequency-dependent
manner, closely conforming to what is predicted if the oddity effect is responsible for their behavior. Using foraging activity
of individuals as a means to evaluate their predation risk, I demonstrate with shoals comprising 12 threespine sticklebacks
(Gasterosteus aculeatus) that large fish forage least actively when in a shoal consisting of 2 large and 10 small fish. An increase in the number
of large fish to 4 among 8 small individuals clearly results in an increase in their foraging activity. However, having reached
an equal frequency with small fish in a shoal, large fish do not seem to change their foraging activity much even when their
number in a shoal increases further. In contrast, foraging activity of small sticklebacks remains fairly constant throughout
the entire range of tested shoal compositions, providing further evidence that small and large fish respond to their oddity
differently.
Received: 12 February 1998 / Accepted after revision: 7 May 1998 相似文献
20.
Katrine Banke Nørgaard Nina Cedergreen 《Environmental science and pollution research international》2010,17(4):957-967