全文获取类型
收费全文 | 220篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
废物处理 | 15篇 |
环保管理 | 15篇 |
综合类 | 93篇 |
基础理论 | 27篇 |
污染及防治 | 49篇 |
评价与监测 | 13篇 |
社会与环境 | 9篇 |
出版年
2020年 | 2篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2015年 | 4篇 |
2014年 | 8篇 |
2013年 | 6篇 |
2012年 | 6篇 |
2011年 | 7篇 |
2010年 | 8篇 |
2009年 | 6篇 |
2008年 | 14篇 |
2007年 | 13篇 |
2006年 | 9篇 |
2005年 | 5篇 |
2004年 | 13篇 |
2003年 | 4篇 |
2002年 | 9篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1988年 | 2篇 |
1983年 | 3篇 |
1978年 | 2篇 |
1966年 | 3篇 |
1965年 | 2篇 |
1964年 | 4篇 |
1961年 | 5篇 |
1960年 | 3篇 |
1959年 | 6篇 |
1957年 | 4篇 |
1956年 | 1篇 |
1955年 | 3篇 |
1954年 | 3篇 |
1953年 | 1篇 |
1952年 | 4篇 |
1950年 | 3篇 |
1948年 | 2篇 |
1942年 | 1篇 |
1941年 | 1篇 |
1933年 | 1篇 |
1931年 | 1篇 |
1920年 | 1篇 |
1915年 | 1篇 |
排序方式: 共有221条查询结果,搜索用时 31 毫秒
191.
Barel-Cohen K Shore LS Shemesh M Wenzel A Mueller J Kronfeld-Schor N 《Journal of environmental management》2006,78(1):16-23
Natural (estradiol, estrone, testosterone, estriol) and synthetic hormones (ethinylestradiol) are constantly excreted into the environment from human and animal sources but little is known of their transport. The purpose of this study was to determine how far along a 100 km river course that hormones could be detected after contamination with sewage effluent or fishpond effluent. Fourteen sites in the Lower Jordan River drainage were sampled (two sites above the sewage effluent contamination, eight sites below the contamination and four tributaries) before and after the dry season of 2002 (Spring and Fall). Samples were tested for testosterone, estrogen (estrone and estradiol combined), estriol, ethinylestradiol, ammonia and fecal coli. It was found that the fecal coli count dropped exponentially (from 250,000 to 60/100 ml3) and the ammonia dropped from 15 to less than 1mg/l over the initial 25 km stretch. Over the same stretch, the hormone values declined by half from their maximum values for testosterone (3.3 ng/l), estriol (8.8 ng/l), ethinylestradiol (6.1 ng/l), and estrogen (4.9 ng/l). From 67 to 100 km mark, testosterone (4.8 ng/l) and estrogen (2.4 ng/l) were still elevated while ethinylestradiol and estriol were >or=1.5 ng/l. The high level of testosterone and estrogen between 67 and 100 km marks was probably due to major discharge from fishponds between 23 and 27 km marks. Levels of ethinylestradiol above 1 ng/l, a level which can affect fish, was seen in 70% (12/16) of the samples tested. The data suggest that hormones in readily measured quantities can be transported considerable distances from the source of pollution. 相似文献
192.
Gutiérrez Miriam Molero Rafael Gaju Miquel van der Steen Josef Porrini Claudio Ruiz José Antonio 《Environmental science and pollution research international》2020,27(10):10436-10448
Environmental Science and Pollution Research - Nectar of honeybee colonies has been used in order to identify heavy metals and establish the benefit of this type of studies as a tool for... 相似文献
193.
Methanotrophic activity in a diffusive methane/oxygen counter-gradient in an unsaturated porous medium 总被引:1,自引:0,他引:1
Microbial methane (CH4) oxidation is a main control on emissions of this important greenhouse gas from ecosystems such as contaminated aquifers or wetlands under aerobic onditions. Due to a lack of suitable model systems, we designed a laboratory column to study this process in diffusional CH4/O2 counter-gradients in unsaturated porous media. Analysis and simulations of the steady-state CH4, CO2 and O2 gas profiles showed that in a 15-cm-deep active zone, CH4 oxidation followed first-order kinetics with respect to CH4 with a high apparent first-order rate constant of approximately 30 h(-1). Total cell counts obtained using DAPI-staining suggested growth of methanotrophic bacteria, resulting in a high capacity for CH4 oxidation. This together with apparent tolerance to anoxic conditions enabled a rapid response of the methanotrophic community to changing substrate availability, which was induced by changes in O2 concentrations at the top of the column. Microbial oxidation was confirmed by a approximately 7 per thousand enrichment in CH4 stable carbon isotope ratios along profiles. Using a fractionation factor of 1.025+/-0.0005 for microbial oxidation estimated from this shift and the fractionation factor for diffusion, simulations of isotope profiles agreed well with measured data confirming large fractionation associated with microbial oxidation. The designed column should be valuable for investigating response of methanotrophic bacteria to environmental parameters in future studies. 相似文献
194.
195.
196.
Josef Brechler 《Environmental monitoring and assessment》2000,65(1-2):269-275
Results of relatively simple gaussian dispersion model are presented. This model, developed in the beginning of this decade, is suitable mainly for determination of spatial distributions of annual mean concentrations of such kinds of air-pollution as sulphur dioxide (SO2), mixture of nitrogen oxides (NOx) or suspended particulate matter (SPM) from all types of emission sources located within the city - point sources, line sources and area sources. Model has been used in years 1994, 1996 and 1998 to assess the air-pollution distributions of the above mentioned kinds in the Prague area and the development of the air quality state. It contributed to the decision making process when possible impact of some changes in traffic system or in system of domestic heating, for example, has been investigated. In this contribution, behaviour of sulphur dioxide (SO2) and mixture of nitrogen oxides (NOx) ground concentration distributions are analyzed with respect to changing emission situation in Prague in recent years. Results show that SO2 ground concentration level decreases mainly due to changes in local heating methods and type of fuel used. Different trend can be seen in NOx ground concentrations thanks to rapid increase in the traffic density. 相似文献
197.
198.
199.
Rebeka Fisseha Matthias Saurer Maya Jäggi Rolf T.W. Siegwolf Josef Dommen Sönke Szidat Vera Samburova Urs Baltensperger 《Atmospheric environment (Oxford, England : 1994)》2009,43(2):431-437
Stable carbon isotope ratio (δ13C) data can provide important information regarding the sources and the processing of atmospheric organic carbon species. Formic, acetic and oxalic acid were collected from Zurich city in August–September 2002 and March 2003 in the gas and aerosol phase, and the corresponding δ13C analysis was performed using a wet oxidation method followed by isotope ratio mass spectrometry. In August, the δ13C values of gas phase formic acid showed a significant correlation with ozone (coefficient of determination (r2) = 0.63) due to the kinetic isotope effect (KIE). This indicates the presence of secondary sources (i.e. production of organic acids in the atmosphere) in addition to direct emission. In March, both gaseous formic and acetic acid exhibited similar δ13C values and did not show any correlation with ozone, indicating a predominantly primary origin. Even though oxalic acid is mainly produced by secondary processes, the δ13C value of particulate oxalic acid was not depleted and did not show any correlation with ozone, which may be due to the enrichment of 13C during the gas - aerosol partitioning.The concentrations and δ13C values of the different aerosol fractions (water soluble organic carbon, water insoluble organic carbon, carbonate and black carbon) collected during the same period were also determined. Water soluble organic carbon (WSOC) contributed about 60% to the total carbon and was enriched in 13C compared to other fractions indicating a possible effect of gas - aerosol partitioning on δ13C of carbonaceous aerosols. The carbonate fraction in general was very low (3% of the total carbon). 相似文献
200.
Roberto Delogu Andrea Battistone Gabriele Buttinelli Stefano Fiore Stefano Fontana Concetta Amato Karen Cristiano Sabine Gamper Josef Simeoni Rita Frate Laura Pellegrinelli Sandro Binda Licia Veronesi Roberta Zoni Paolo Castiglia Andrea Cossu Maria Triassi Francesca Pennino Cinzia Germinario Viviana Balena Antonella Cicala Pietro Mercurio Lucia Fiore Carlo Pini Paola Stefanelli 《Food and environmental virology》2018,10(4):333-342
Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the ‘WHO global polio eradication program’, is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population. 相似文献