全文获取类型
收费全文 | 1425篇 |
免费 | 6篇 |
国内免费 | 42篇 |
专业分类
安全科学 | 45篇 |
废物处理 | 86篇 |
环保管理 | 142篇 |
综合类 | 240篇 |
基础理论 | 340篇 |
环境理论 | 1篇 |
污染及防治 | 394篇 |
评价与监测 | 101篇 |
社会与环境 | 118篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 13篇 |
2022年 | 46篇 |
2021年 | 9篇 |
2020年 | 6篇 |
2019年 | 14篇 |
2018年 | 54篇 |
2017年 | 22篇 |
2016年 | 28篇 |
2015年 | 49篇 |
2014年 | 35篇 |
2013年 | 120篇 |
2012年 | 36篇 |
2011年 | 63篇 |
2010年 | 61篇 |
2009年 | 72篇 |
2008年 | 70篇 |
2007年 | 60篇 |
2006年 | 44篇 |
2005年 | 43篇 |
2004年 | 77篇 |
2003年 | 65篇 |
2002年 | 43篇 |
2001年 | 102篇 |
2000年 | 43篇 |
1999年 | 24篇 |
1998年 | 16篇 |
1997年 | 12篇 |
1996年 | 9篇 |
1995年 | 20篇 |
1994年 | 7篇 |
1993年 | 9篇 |
1992年 | 15篇 |
1991年 | 10篇 |
1990年 | 11篇 |
1989年 | 10篇 |
1988年 | 6篇 |
1987年 | 7篇 |
1985年 | 8篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1980年 | 6篇 |
1975年 | 8篇 |
1974年 | 10篇 |
1973年 | 7篇 |
1972年 | 12篇 |
1971年 | 5篇 |
1966年 | 5篇 |
1965年 | 5篇 |
1959年 | 5篇 |
1957年 | 5篇 |
排序方式: 共有1473条查询结果,搜索用时 125 毫秒
691.
Z. Hlgye 《Journal of environmental radioactivity》2008,99(10):1653
Monitoring of 239,240Pu in surface air of Prague started in 1986 in connection with the Chernobyl accident. Measurable activities of 10–28 μBq m−3 were found from 29 April 1986 to 5 May 1986. In the most of the monitoring periods of 1987–1996, activities of 239,240Pu in air were not measurable. Positive values for 239,240Pu and 238Pu in air could be obtained after installation of an aerosol sampler with higher flow-rate in 1997. Activity concentrations of 239,240Pu and 238Pu in Prague air in the most of quarters of 1997–2006 were in the range 0.53–5.06 and <0.16–1.10 nBq m−3, respectively. Seasonal fluctuations can be found in content of 239,240Pu in air. Activity ratios of 238Pu/239,240Pu in air are higher than those in top soil, so it can be supposed that 238Pu is coming to air of Prague also from other sources than resuspension of fallout from atmospheric nuclear tests. 相似文献
692.
693.
The populations of many North American landbirds are showing signs of declining. Gathering information on breeding productivity
allows critical assessment of population performance and helps identify good habitat-management practices. He (Biometrics
(2003) 59 962–973) proposed a Bayesian model to estimate the age-specific nest survival rates. The model allows irregular
visiting schedule under the assumption that the observed nests have homogeneous nest survival. Because nest survival studies
are often conducted in different sites and time periods, it is not realistic to assume homogeneous nest survival. In this
paper, we extend He’s model by incorporating these factors as categorical covariates. The simulation results show that the
Bayesian hierarchical model can produce satisfactory estimates on nest survival and capture different factor effects. Finally
the model is applied to a Missouri red-winged blackbird data set. 相似文献
694.
695.
S.Z. Cohen 《Journal of environmental science and health. Part. B》2013,48(3):345-352
Abstract Scientific and regulatory interest in ground water contamination by pesticides increased significantly in 1979. This was prompted by findings of the nematicide 1,2‐dibromo‐3‐chloropropane (DBCP) and the nematicide/insecticide aldicarb (Temik®) in ground water in several states. Since that time, at least 130 pesticides and pesticide metabolites have been detected in ground water in over 150 studies, but detection frequencies are 4–10% nationally. Detection frequencies of pesticides over Health Advisory Levels are generally lower. Screening‐level models and detailed computer simulation models are useful for risk assessments and regulatory decisions. Attenuation Factor, CMLS, PRZM2, GLEAMS, and LEACHM are all useful models. 相似文献
696.
Cheryl M. E. McCrindle Marianna Siegmund-Schultze Alexander W. Heeb Anne Valle Zárate Shashi Ramrajh 《Environment, Development and Sustainability》2013,15(5):1245-1257
Game harvesting in South Africa generally leaves behind edible by-products, which could be a low-cost source of protein for poor people in rural areas. Seven professional and nine recreational hunters were interviewed, a game harvest and trophy hunt attended and literature reviewed, in order to describe the food value chain for game and ways in which edible by-products could be legally channelled into the human food chain, rather than being left in the field for scavengers. Practices of informal vendors (n = 51) were assessed using structured interviews, observation and microbiological analysis. In an experiment, inspected game by-products (shinbones from impala and springbok) were provided to eight informal traders for cooking at an informal market and microbiological analysis was done before and after preparation. The results showed that providing edible by-products to poor consumers appears to be culturally acceptable, affordable, accessible and safe. A crossover from formal to informal marketing is recommended as it would enhance traceability and safety of the product and minimise the risk of poaching. It is suggested that methods should be developed which make the distribution of edible by-products to vulnerable rural communities feasible. 相似文献
697.
K. Lebecki J.
li K. Cybulski Z. Dyduch 《Journal of Loss Prevention in the Process Industries》2001,14(6):489-494
The paper describes large-scale tests of triggered barriers of different design. Main stress was put on examining suitability of the flame detector developed in US Bureau of Mines to work as a trigger for the barriers. It was found that the detector works satisfactorily with the barriers of different design providing a suitable mean to suppress explosions in galleries, either in mines or in other industries. 相似文献
698.
This study uses DAYCENT model to investigate the sensitivity of soil organic carbon (SOC) at an intensely cultivated site in the U.S. Midwest under an ensemble of scenario climates predicted by IPCC models. The model ensemble includes three IPCC models (Canadian, French, German), three emission scenarios (B1, A1B, A2) and three time periods (late 20th, mid-21st, late 21st century). DAYCENT shows that SOC at the site would decline by 0.3-2.6 kg m−2 (5-35%) depending on the models and scenarios from late 20th to mid-21st century despite a larger increase of future net primary production (NPP) than respiration. The future SOC decrease is mostly attributable to harvest loss. The wide spread in future SOC decline rates are in part because SOC decrease (by respiration) is directly proportional to SOC itself. Any uncertainty in absolute SOC in DAYCENT would translate directly into its trend, unlike other variables such as temperature whose trends are independent of their values themselves, contrasting the reliability of SOC trend with temperature change. 相似文献
699.
S. A. Murzina N. N. Nemova Z. A. Nefedova S. Falk-Petersen 《Russian Journal of Ecology》2010,41(1):51-54
A comparative study on the lipid composition of the liver and muscles has been performed in daubed shanny caught in summer
(July) in Arctic waters at three different sites (biotopes) along the north-western coast of Spitsbergen. In marine organisms
living at high latitudes, lipids play an especially important role, primarily as reserve substances and as a factor influencing
adaptation to severe environmental conditions. Since the ecology of daubed shanny is poorly known, the data obtained may be
considered novel. 相似文献
700.
It is well recognised that local ecological knowledge is an important facet of natural resource management in rural regions of the developing world. However, techniques to assess levels and to integrate it into formal or informal management approaches require further development. In particular, quantitative tools are missing, which would allow more robust analysis of the factors that positively or negatively affect local ecological knowledge and vice versa. This paper reports on a quick assessment approach that provides a quantitative score of generalist local ecological knowledge at the household level. It does so by comparing responses to the knowledge of local people identified as experts within the community. In this way it is both locally constructed and contextualized, and thereby avoids pitfalls of trying to score local ecological knowledge relative to conventional scientific knowledge which frequently cannot account for local constructs. The approach is applied at eight villages throughout the savanna biome in South Africa. 相似文献