全文获取类型
收费全文 | 98283篇 |
免费 | 1257篇 |
国内免费 | 1150篇 |
专业分类
安全科学 | 3674篇 |
废物处理 | 3688篇 |
环保管理 | 14715篇 |
综合类 | 21836篇 |
基础理论 | 27591篇 |
环境理论 | 81篇 |
污染及防治 | 18147篇 |
评价与监测 | 6013篇 |
社会与环境 | 4344篇 |
灾害及防治 | 601篇 |
出版年
2022年 | 884篇 |
2021年 | 977篇 |
2020年 | 717篇 |
2019年 | 956篇 |
2018年 | 1407篇 |
2017年 | 1457篇 |
2016年 | 2457篇 |
2015年 | 1970篇 |
2014年 | 2806篇 |
2013年 | 9581篇 |
2012年 | 2631篇 |
2011年 | 3135篇 |
2010年 | 3568篇 |
2009年 | 3616篇 |
2008年 | 2649篇 |
2007年 | 2549篇 |
2006年 | 2769篇 |
2005年 | 2604篇 |
2004年 | 2915篇 |
2003年 | 2684篇 |
2002年 | 2248篇 |
2001年 | 2626篇 |
2000年 | 2100篇 |
1999年 | 1530篇 |
1998年 | 1359篇 |
1997年 | 1353篇 |
1996年 | 1472篇 |
1995年 | 1626篇 |
1994年 | 1519篇 |
1993年 | 1358篇 |
1992年 | 1363篇 |
1991年 | 1325篇 |
1990年 | 1265篇 |
1989年 | 1237篇 |
1988年 | 1080篇 |
1987年 | 1007篇 |
1986年 | 998篇 |
1985年 | 1071篇 |
1984年 | 1168篇 |
1983年 | 1178篇 |
1982年 | 1184篇 |
1981年 | 1101篇 |
1980年 | 949篇 |
1979年 | 934篇 |
1978年 | 832篇 |
1977年 | 724篇 |
1976年 | 648篇 |
1974年 | 620篇 |
1973年 | 653篇 |
1972年 | 665篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Charlotte R. Dromard Mathilde Guéné Yolande Bouchon-Navaro Soazig Lemoine Sébastien Cordonnier Claude Bouchon 《Environmental science and pollution research international》2018,25(15):14294-14301
Chlordecone is an organochlorine pesticide, used in the Lesser Antilles from 1972 to 1993 to fight against a banana weevil. That molecule is very persistent in the natural environment and ends up in the sea with runoff waters. The objective of the present study is to evaluate the level of contamination in several trophic groups of marine animals according to their distance from the source of pollution. Samples of suspended matter, macroalgae, herbivorous fishes, detrivorous crustaceans, zooplanktivorous fishes, first- and second-order of carnivorous fishes, and piscivorous fishes have been collected in two sites, located downstream the contaminated sites (Goyave and Petit-Bourg), in three marine habitats (coastal mangroves, seagrass beds located 1.5 km from the shoreline, and coral reefs at 3 km offshore). Animals collected in mangroves were the most contaminated (mean concentrations 193 μg kg?1 in Goyave and 213 μg kg?1 in Petit-Bourg). Samples from seagrass beds presented intermediate concentrations of chlordecone (85 μg kg?1 in Goyave and 107 μg kg?1 in Petit-Bourg). Finally, samples from coral reefs were the less contaminated (71 μg kg?1 in Goyave and 74 μg kg?1 in Petit-Bourg). Reef samples, collected 3 km offshore, were two to three times less contaminated than those collected in mangroves. 相似文献
62.
The influence of horizontal structure of spruce forest on the spatial distribution of acid-soluble Zn, Cd, Pb compounds and 137Cs in the litter and the humus horizon of soddy podzolic soil has been studied in the territory with the regional background level of industrial fallout. It has been found that the distribution pattern of Zn in the forest litter is a result of biogeochemical processes. The litter in fern–wood sorrel microplots contains increased amounts of Zn and Cd, while the contents of Pb and 137Cs are decreased. The distribution patterns of Pb and 137Cs in the litter are positively correlated with each other, since both elements are deposited from the atmosphere, and similar mechanisms account for their redistribution in the spruce forest ecosystem. 相似文献
63.
64.
Patricia Blanco-Piñeiro M. Pino Díaz-Pereira Aurora Martínez Vidal 《International journal of occupational safety and ergonomics》2018,24(2):316-323
Objective. Bad posture increases the risk that a musician may suffer from musculoskeletal disorders. This study compared posture quality required by different instruments or families of instruments. Methods. Using an ad-hoc postural observation instrument embracing 11 postural variables, four experts evaluated the postures of 100 students attending a Spanish higher conservatory of music. Results. The agreement of the experts’ evaluations was statistically confirmed by a Cohen's κ value between 0.855 and 1.000 and a Kendall value between 0.709 and 1.000 (p?0.001 in all cases). Moreover, χ2 tests revealed significant association between instrument families and seated posture with respect to pelvic attitude, dorsal curvature and head alignment in both sagittal and frontal planes. This analysis also showed an association between instrument families and standing posture with respect to the frontal plane of the axis of gravity, pelvic attitude, head alignment in the frontal plane, the sagittal plane of the shoulders and overall posture. Conclusions. While certain postural defects appear to be common to all families of instruments, others are more characteristic of some families than others. The instrument associated with the best posture quality was the bagpipe, followed by percussion and strings. 相似文献
65.
Mary L. Smiley C. Raymond Bingham Peter D. Jacobson Michelle L. Macy 《Traffic injury prevention》2018,19(3):326-331
Objectives: In this study, we sought to accomplish the following objectives: to (1) calculate the percentage of children considered appropriately restrained across 8 criteria of increasing restrictiveness; (2) examine agreement between age- and size-based appropriateness criteria; (3) assess for changes in the percentage of children considered appropriately restrained by the 8 criteria between 2011 (shortly after updates to U.S. guidelines) and 2015.Methods: Data from 2 cross-sectional surveys of 928 parents of children younger than 12 years old (n = 591 in 2011, n = 337 in 2015) were analyzed in 2017. Child age, weight, and height were measured at an emergency department visit and used to determine whether the parent-reported child passenger restraint was considered appropriate according to 8 criteria. Age-based criteria were derived from Michigan law and U.S. guidelines. Weight, height, and size-based criteria were derived from typical restraints available in the United States in 2007 and 2011. The percentage appropriate restraint use was calculated for each criterion. The kappa statistic was used to measure agreement between criteria. Change in appropriateness from 2011 to 2015 was assessed with chi-square statistics.Results: Percentage appropriate restraint use varied from a low of 19% for higher weight limits in 2011 to a high of 91% for Michigan law in 2015. Agreement between criteria was slight to moderate. The lowest kappa was for Michigan law and higher weight limits in 2011 (κ = 0.06) and highest for U.S. guidelines and lower weight limits in 2011 (κ = 0.60). Percentage appropriate restraint use was higher in 2015 than 2011 for the following criteria: U.S. guidelines (74 vs. 58%, P < .001), lower weight (57 vs. 47%, P = .005), higher weight (25 vs. 19%, P = .03), greater height (39 vs. 26%, P < .001), and greater size (42 vs. 30%, P = .001).Conclusions: The percentage of children considered to be using an appropriate restraint varied substantially across criteria. Aligning the definition of appropriate restraint use with current U.S. guidelines would increase consistency in reporting results from studies of child passenger safety in the United States. Potential explanations for the increased percentage of children considered appropriately restrained between 2011 and 2015 include adoption of the updated U.S. guidelines and the use of child passenger restraints with higher weight and height limits. 相似文献
66.
In this paper, we assert and test the proposition that environmental disclosure (ED) is structured by institutionalised myths and that is why ED is decoupled from environmental performance and media pressures. Focusing on firms from Canada, France and Germany, findings show that ED mimetic isomorphism for different topics varies among countries and by industry sensitiveness to the environment. The results corroborate the institutional presumption that institutionalised myths vary among different contexts. Our findings also suggest that institutionalised ED structures may not reflect environmental performance, mimetic patterns being affected by environmental performance. However, the decoupling between ED mimetic isomorphism and environmental performance decrease when firms’ ED credibility is questioned by the media. 相似文献
67.
Cattle vaccination records question the impact of recent zero-deforestation agreements in the Amazon
Regional Environmental Change - In the late 2000s, slaughterhouses across the Amazon entered into a series of agreements designed to reduce the environmental impact of the local cattle sector. In... 相似文献
68.
del Mar Delgado-Serrano Maria Oteros-Rozas Elisa Ruiz-Mallén Isabel Calvo-Boyero Diana Ortiz-Guerrero Cesar Enrique Escalante-Semerena Roberto Ivan Corbera Esteve 《Regional Environmental Change》2018,18(2):593-593
Regional Environmental Change - The published online version contains mistake. Author name was incorrectly captured. Instead of Maria del Mar Delgado-Serrano was incorrectly captured as Ma del Mar... 相似文献
69.
Regional Environmental Change - The rapid environmental changes currently underway in many dry regions of the world, and the deep uncertainty about their consequences, underscore a critical... 相似文献
70.
Smith Erin F. Lieske Scott N. Keys Noni Smith Timothy F. 《Regional Environmental Change》2018,18(4):1185-1199
Regional Environmental Change - Research that projects biophysical changes under climate change is more advanced than research that projects socio-economic changes. There is a need in adaptation... 相似文献