全文获取类型
收费全文 | 265篇 |
免费 | 0篇 |
国内免费 | 4篇 |
专业分类
安全科学 | 15篇 |
废物处理 | 20篇 |
环保管理 | 54篇 |
综合类 | 22篇 |
基础理论 | 56篇 |
污染及防治 | 73篇 |
评价与监测 | 19篇 |
社会与环境 | 10篇 |
出版年
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 8篇 |
2017年 | 2篇 |
2016年 | 5篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 26篇 |
2012年 | 15篇 |
2011年 | 10篇 |
2010年 | 15篇 |
2009年 | 8篇 |
2008年 | 6篇 |
2007年 | 9篇 |
2006年 | 21篇 |
2005年 | 10篇 |
2004年 | 7篇 |
2003年 | 7篇 |
2002年 | 11篇 |
2001年 | 7篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1984年 | 3篇 |
1982年 | 3篇 |
1981年 | 6篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1973年 | 2篇 |
1971年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1961年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有269条查询结果,搜索用时 15 毫秒
181.
Sabra L. Klein H. Ray Gamble Randy J. Nelson 《Behavioral ecology and sociobiology》1999,45(5):323-329
Females may choose mates based on secondary sex traits that reflect disease resistance. Accordingly, females should be able
to distinguish between unparasitized and parasitized males, and should prefer to mate with unparasitized individuals. Mate
and odor preferences for uninfected males or males infected with the nematode, Trichinella spiralis, were examined among prairie voles (Microtus ochrogaster) and meadow voles (M. pennsylvanicus). In a 15-min odor preference test, only female meadow voles distinguished between bedding from parasitized and unparasitized
conspecific males, and preferred to spend time with bedding from unparasitized males. Although T. spiralis infection influenced odor preference in female meadow voles, there was no effect of infection status on mate preference among
either species. Testosterone and corticosterone concentrations were not different between parasitized and unparasitized males.
However, among prairie voles, males that spent an increased amount of time with females during the mate preference test had
elevated testosterone concentrations. Taken together, these data suggest that (1) female meadow voles can discriminate between
unparasitized and parasitized males, (2) the effects of infection on steroid hormone concentrations may be masked by the effects
of social interactions, and (3) parasites may represent a selective constraint on partner preference in voles; however, the
life cycle of parasites may influence female preference and should be considered in studies of female preference.
Received: 23 April 1998 / Accepted after revision: 25 October 1998 相似文献
182.
J. O. Ivie M. D. Thomas O. C. Taylor C. Ray Thompson W. M. Dugger JR. B. L. Richards 《Journal of the Air & Waste Management Association (1995)》2013,63(8):355-359
A discussion of the methods used to determine the most economic design of chimney for a new thermal power station or large industrial plant is presented, with the objective that ground level concentration of pollutants will be kept at a minimum. Attention is paid to the geography and climatology of the site, with special reference to the frequency and height of inversions and the prevailing wind direction and speed. A method is illustrated in using a large thermal power station as an example. The maximum sulfur dioxide concentrations at ground level are computed for several chimney heights and gas exit velocities. The values of these sulfur dioxide concentrations, the capital cost of the chimney, the pumping costs, and the gas pressures within the chimney are considered in selecting a suitable chimney height and a gas exit velocity which will meet most economically the stated objective. The paper deals primarily with chimneys for industrial or power boiler plant of maximum continuous rating greater than 450 million Btu/hr (about 450,000 lbs of steam/hr), or to chimneys serving furnaces burning fuel at a maximum rate greater than 50,000 lbs/hr of coal, or 80,000 lbs/hr of oil. For chimneys serving plant with smaller heat inputs, chimney selection by reference to Clean Air Act 1956, Memorandum on Chimney Heights is suggested. 相似文献
183.
Kinetic assessment of the potassium ferrate(VI) oxidation of antibacterial drug sulfamethoxazole 总被引:1,自引:0,他引:1
Sulfamethoxazole (SMX), a worldwide-applied antibacterial drug, was recently found in surface waters and in secondary wastewater effluents, which may result in ecotoxical effects in the environment. Herein, removal of SMX by environmentally-friendly oxidant, potassium ferrate(VI) (K(2)FeO(4)), is sought by studying the kinetics of the reaction between Fe(VI) and SMX as a function of pH (6.93-9.50) and temperature (15-45 degrees C). The rate law for the oxidation of SMX by Fe(VI) is first-order with respect to each reactant. The observed second-order rate constant decreased non-linearly from 1.33+/-0.08 x 10(3) M(-1)s(-1) to 1.33+/-0.10 x 10(0) M(-1)s(-1) with an increase of pH from 7.00 to 9.50. This is related to protonation of Fe(VI) (HFeO(4)(-) <==> H(+) + FeO(4)(2-); pK(a,HFeO(4)) = 7.23) and sulfamethoxazole (SH <==> H(+) + S(-); pK(a,SH)=5.7). The estimated rate constants were k(11)(HFeO(4)(-) + SH) = 3.0 x 10(4) M(-1)s(-1), k(12)(HFeO(4)(-) + S(-)) = 1.7 x 10(2) M(-1)s(-1), and k(13) (FeO(4)(2-) + SH) = 1.2 x 10(0) M(-1)s(-1). The energy of activation at pH 7.0 was found to be 1.86+/-0.04 kJ mol(-1). If excess potassium ferrate(VI) concentration (10 microM) is used than the SMX in water, the half-life of the reaction using a rate constant obtained in our study would be approximately 2 min at pH 7. The reaction rates are pH dependent; thus, so are the half-lives of the reactions. The results suggest that K(2)FeO(4) has the potential to serve as an oxidative treatment chemical for removing SMX in water. 相似文献
184.
Evans CD Caporn SJ Carroll JA Pilkington MG Wilson DB Ray N Cresswell N 《Environmental pollution (Barking, Essex : 1987)》2006,143(3):468-478
A simple model of nitrogen (N) saturation, based on an extension of the biogeochemical model MAGIC, has been tested at two long-running heathland N manipulation experiments. The model simulates N immobilisation as a function of organic soil C/N ratio, but permits a proportion of immobilised N to be accompanied by accumulation of soil carbon (C), slowing the rate of C/N ratio change and subsequent N saturation. The model successfully reproduced observed treatment effects on soil C and N, and inorganic N leaching, for both sites. At the C-rich upland site, N addition led to relatively small reductions in soil C/N, low inorganic N leaching, and a substantial increase in organic soil C. At the C-poor lowland site, soil C/N ratio decreases and N leaching increases were much more dramatic, and soil C accumulation predicted to be smaller. The study suggests that (i) a simple model can effectively simulate observed changes in soil and leachate N; (ii) previous model predictions based on a constant soil C pool may overpredict future N leaching; (iii) N saturation may develop most rapidly in dry, organic-poor, high-decomposition systems; and (iv) N deposition may lead to significantly enhanced soil C sequestration, particularly in wet, nutrient-poor, organic-rich systems. 相似文献
185.
Byung Kyu Kim Jamie Krams Erin Krug Mark Leaseburge Justin Lemley Ammar Alkhawaldeh Ray A. Mentzer M. Sam Mannan 《Journal of Loss Prevention in the Process Industries》2012,25(5):780-787
Several catastrophic events in the process industry have caused extensive damage to life and property and have forever changed the process safety landscape. Despite the commitment from the industry, incidents still occur with similar root causes, impacting major companies in various ways. This work examines the financial impact of such incidents on the stability and future of affected companies in different industries. Several devastating incidents were analyzed to evaluate the direct impact in the short- and long-term and to discuss factors influencing the ability of affected companies to withstand the consequence of catastrophic events. 相似文献
186.
187.
Wen‐Cheng Liu Ming‐Hsi Hsu Shu‐Yi Chen Chi‐Ray Wu Albert Y. Kuo 《Journal of the American Water Resources Association》2005,41(2):425-436
ABSTRACT: The penetration of sunlight into the water column plays a critical role in the aquatic ecosystem. This study investigates light attenuation through the water column of the Danshuei River estuary and explores the models for quantifying it. The measurement of photosynthetically active radiation (PAR) indicates that the conventional exponential attenuation of light with depth is a very good model. A light attenuation coefficient may be derived from the PAR measurements at each location. The simpler measurements of Secchi depth (SD) provide an approximate estimate of the attenuation coefficients through an inverse linear relationship. The results also reveal that the amount and kinds of materials, which are either dissolved or suspended in the water, control light attenuation through the water column. However, the linear regression with such a model results in very poor correlation, and a relatively large constant term for the Danshuei River estuary. The regression with salinity yields a good correlation, indicating that the fraction of sea water might be a good parameter for estimating light attenuation coefficient for practical application in the Danshuei River estuary. 相似文献
188.
Hansford GM Freshwater RA Bosch RA Cox RA Jones RL Pratt KF Williams DE 《Journal of environmental monitoring : JEM》2005,7(2):158-162
The design of an instrument based on a solid state tungsten oxide sensor for making profile measurements of atmospheric ozone from balloon platforms is described. The sensor is operated at a constant temperature, typically 530 [degree]C. The importance of a detailed consideration of the electronic design is demonstrated, with particular reference to the circuit to control the sensor heater. Calibration methods which are straightforward to implement are illustrated, and the results of a test flight alongside an electrochemical ozonesonde are shown. Quantitative agreement within 25% for most of the profile demonstrates the potential of this type of sensor for ozone sounding. Future improvements from manufacture to analysis are expected to improve on this. 相似文献
189.
190.