全文获取类型
收费全文 | 14338篇 |
免费 | 100篇 |
国内免费 | 154篇 |
专业分类
安全科学 | 349篇 |
废物处理 | 595篇 |
环保管理 | 1559篇 |
综合类 | 3238篇 |
基础理论 | 3338篇 |
环境理论 | 6篇 |
污染及防治 | 3571篇 |
评价与监测 | 1103篇 |
社会与环境 | 762篇 |
灾害及防治 | 71篇 |
出版年
2022年 | 127篇 |
2021年 | 107篇 |
2019年 | 100篇 |
2018年 | 195篇 |
2017年 | 202篇 |
2016年 | 299篇 |
2015年 | 226篇 |
2014年 | 399篇 |
2013年 | 1023篇 |
2012年 | 448篇 |
2011年 | 584篇 |
2010年 | 471篇 |
2009年 | 525篇 |
2008年 | 564篇 |
2007年 | 577篇 |
2006年 | 537篇 |
2005年 | 495篇 |
2004年 | 451篇 |
2003年 | 455篇 |
2002年 | 430篇 |
2001年 | 595篇 |
2000年 | 372篇 |
1999年 | 260篇 |
1998年 | 147篇 |
1997年 | 164篇 |
1996年 | 171篇 |
1995年 | 188篇 |
1994年 | 179篇 |
1993年 | 131篇 |
1992年 | 164篇 |
1991年 | 172篇 |
1990年 | 168篇 |
1989年 | 141篇 |
1988年 | 156篇 |
1987年 | 96篇 |
1986年 | 128篇 |
1985年 | 127篇 |
1984年 | 122篇 |
1983年 | 114篇 |
1982年 | 120篇 |
1981年 | 120篇 |
1980年 | 87篇 |
1979年 | 99篇 |
1978年 | 101篇 |
1976年 | 92篇 |
1974年 | 104篇 |
1972年 | 87篇 |
1971年 | 85篇 |
1967年 | 100篇 |
1964年 | 92篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
K S Liu S B Hayward J R Girman B A Moed F Y Huang 《Journal of the Air & Waste Management Association》1991,41(9):1207-1212
A study was conducted to determine the annual average radon concentrations in California residences, to determine the approximate fraction of the California population regularly exposed to radon concentrations of 4 pCi/l or greater, and to the extent possible, to identify regions of differing risk for high radon concentrations within the state. Annual average indoor radon concentrations were measured with passive (alpha track) samplers sent by mail and deployed by home occupants, who also completed questionnaires on building and occupant characteristics. For the 310 residences surveyed, concentrations ranged from 0.10 to 16 pCi/l, with a geometric mean of whole-house (bedroom and living room) average concentrations of 0.85 pCi/l and a geometric standard deviation of 1.91. A total of 88,000 California residences (0.8 percent) were estimated to have radon concentrations exceeding 4 pCi/l. When the state was divided into six zones based on geology, significant differences in geometric mean radon concentrations were found between several of the zones. Zones with high geometric means were the Sierra Nevada mountains, the valleys east of the Sierra Nevada, the central valley (especially the southern portion), and Ventura and Santa Barbara Counties. Zones with low geometric means included most coastal counties and the portion of the state from Los Angeles and San Bernardino Counties south. 相似文献
972.
973.
974.
W. G. K. Taylor 《组织行为杂志》1989,10(4):297-307
Although the Kirton Adaption - Innovation Inventory (KAI) has almost always been used as a single scale purporting to measure a dimension of cognitive style, the KAI Manual characterizes three factors. This paper provides further confirmatory evidence of the structure of the three-factor model and of the high reliability coefficients of the three subscales. However, it questions whether three factors are sufficient and examines four- and five-factor models. Evidence is provided that the ‘O’ subscale in the orthodox three-factor model contains two conceptual elements, a major component concerned with idea generation and a minor component concerned with preference for stability/change. A four-factor model of KAI is proposed and an argument is advanced which leads to concern about the idea generation element of the ‘O’ subscale as a measure purely of cognitive style. Some implications for the development of the KAI are outlined. 相似文献
975.
M. K. Agarwal 《Die Naturwissenschaften》1990,77(4):170-175
Recent advances have challenged classical notions regarding the nature of steroid hormone receptors in the cell including localization, activation, configuration, and stability. Molecular biology has revealed a remarkable similarity in the primary structure of a wide variety of receptor classes that goes beyond steroid action. Post-translational modification of a primary unit, expressed in response to genetic conservatism, would appear to assure receptor dynamics specific to hormone-, organ-, and tissue-dependent processes, and may even lead to toxicity and oncogenicity. 相似文献
976.
977.
978.
A. Milunsky C. Konialis S. H. Shim T. A. Maher K. Spengos M. Ito C. Pangalos 《黑龙江环境通报》2005,25(11):1057-1058
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an important cause of hereditary stroke. Mutations in the Notch3 gene are clearly causally linked to this progressive vascular disorder. Cerebral ischemic attacks, cognitive decline, strokes, and vascular dementia constitute the major manifestations of this disorder. This report details the prenatal detection of a Notch3 mutation in the fetus of a couple where the father had a known mutation in this gene. This is the first report of a prenatal diagnosis of CADASIL, and another example of a serious, highly penetrant, and relentlessly progressive degenerative genetic disorder presenting decades after birth and for which prenatal diagnosis is an option. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
979.
Kishore K Krishnani V Parimala B P Gupta I S Azad Xiaoguang Meng M Abraham 《Water environment research》2006,78(9):938-950
Development of new economically feasible ecofriendly products from agricultural wastes or byproducts for shrimp farm wastewater treatment is the objective of our continued research. Ammonia is a nitrogenous toxicant, which is commonly found in wastewater from shrimp farms. In the present study, we explored the possibility of the use of simply and inexpensively prepared bagasse products so that this abundant crop byproduct could be used to remove ammonia from shrimp farm wastewater. Bagasse, a natural highly fibrous lignocellulosic byproduct of sugarcane, was converted into five different products. Experimental results have shown that ammonia is efficiently removed from wastewater by four bagasse products with a dose of 1 to 6 g/L within 24 hours. The effect of bagasse products on other water quality parameters and growth kinetics of biofilm bacteria onto bagasse fiber have also been studied. Efficacies of products were compared by using statistical analysis. Products developed from bagasse are useful and economical. 相似文献
980.
Assessment of Soil Cover Degradation and Desertification in Northern Lowland Dagestan 总被引:2,自引:0,他引:2
Stasyuk N. V. Dobrovol'skii G. V. Zalibekov Z. G. Saidov A. K. Dobrynin D. V. 《Russian Journal of Ecology》2004,35(3):144-149
New principles of the assessment of soil cover degradation and desertification, the scale and intensity of destructive processes manifestation are determined. 相似文献