全文获取类型
收费全文 | 226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 | 99篇 |
基础理论 | 28篇 |
污染及防治 | 49篇 |
评价与监测 | 13篇 |
社会与环境 | 8篇 |
出版年
2020年 | 2篇 |
2018年 | 6篇 |
2017年 | 3篇 |
2015年 | 3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 | 3篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1988年 | 2篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 2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 |
1955年 | 3篇 |
1954年 | 3篇 |
1952年 | 4篇 |
1950年 | 3篇 |
1948年 | 2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227条查询结果,搜索用时 15 毫秒
101.
Thullner M Mauclaire L Schroth MH Kinzelbach W Zeyer J 《Journal of contaminant hydrology》2002,58(3-4):169-189
Bacterial growth and its interaction with water flow was investigated in a two-dimensional flow field in a saturated porous medium. A flow cell (56 x 44 x 1 cm) was filled with glass beads and operated under a continuous flow of a mineral medium containing nitrate as electron acceptor. A glucose solution was injected through an injection port, simulating a point source contamination. Visible light transmission was used to observe the distribution of the growing biomass and water flow during the experiment. At the end of the experiment (on day 31), porous medium samples were destructively collected and analyzed for abundance of total and active bacterial cells, bacterial cell volume and concentration of polysaccharides and proteins. Microbial growth was observed in two stripes along the length of the flow cell, starting at the glucose injection port, where highest biomass concentrations were obtained. The spatial distribution of biomass indicated that microbial activity was limited by transverse mixing between glucose and nitrate media, as only in the mixing zone between the media high biological activities were achieved. The ability of the biomass to change the flow pattern in the flow cell was observed, indicating that the biomass was locally reducing the hydraulic conductivity of the porous medium. This bioclogging effect became evident when the injection of the glucose solution was turned off and water flow still bypassed the area around the glucose injection port, preserving the flow pattern as it was during the injection of the glucose solution. As flow bypass was possible in this system, the average hydraulic properties of the flow cell were not affected by the produced biomass. Even in the vicinity of the injection port, the total volume of the bacterial cells remained below 0.01% of the pore space and was unlikely to be responsible for the bioclogging. However, the bacteria produced large amounts of extracellular polymeric substances (EPS), which likely caused the observed bioclogging effects. 相似文献
102.
Josef Hoch 《Chemosphere》1983,12(11-12)
The development of eggs of brook trout (Salvelinus fontinalis) in water acidified with hydrochloric acid and sulfuric acid respectively is described. Weight and chloride concentration of the eggs and total length of the alevins are investigated too. 相似文献
103.
Jürgen Schnelle-Kreis Martin Sklorz Anette Peters Josef Cyrys Ralf Zimmermann 《Atmospheric environment (Oxford, England : 1994)》2005,39(40):7702-7714
PM2.5 Particle-associated semi-volatile organic compounds (SVOC) were determined in the city of Augsburg, Germany. Daily samples were collected at a central monitoring station from late summer to late autumn 2002. The concentrations of polycyclic aromatic hydrocarbons (PAH), oxidized PAH (O-PAH), n-alkanes, hopanes and long chain linear alkylbenzenes were determined by direct thermal desorption-gas chromatography-time of flight mass spectrometry (DTD-GC-TOFMS). Additionally, PM2.5 particle mass and number concentrations were measured. The sampling campaign can be divided into two parts, distinguished by a lower temperature level in the second part of the campaign. The particulate mass concentration showed no significant changes, whereas most of the SVOC had significant higher mean and peak concentrations in the colder period. The analysis of the data showed an increased influence of non-traffic sources in the colder period, reflected by a weak shift in the PAH profile and a significant shift in the hopane pattern. Statistical analysis of the inter-group correlations was carried out. Eight clusters partly representing different sources of the aerosol have been identified. 相似文献
104.
105.
Udo Muster Tom Schilling Harald Schobesberger Hertha Luttenberger Rolf Marr Josef Draxler 《Environmental Sciences Europe》1997,9(1):25-32
Waste and process gases from thermal power and metallurgical plants or such products from alkali-chloride industries contain metallic, inorganic and organic mercury. Widespread processes applied to remove the greatest amount of mercury are absorption and adsorption. Caused by the lowering of the emission limit from 200 to 50 µg/m3 [STP] by national and European legislators, considerable efforts have been made to enhance the efficiency of the main separation units of flue gas cleaning plants by applying the appropriate technological measures. This article is focused on the removal of mercury from waste gases. The state of engineering is described, especially with regard to enhancing the efficiency of separation in the raw gas, in wet, dry and quasi-dry processes as well as in tail-end process units. Specially impregnated ceramic carriers can be used for the selective separation of metallic, inorganic and organic mercury. Amalgamation has been investigated as a possible separation mechanism both experimentally and in theory. Using the ceramic reactor, removal rates for gaseous mercury and its compounds can be achieved which are even lower than 50 µg/m3 [STP]. The technology, the separation mechanisms and the ecological advantages through the use of ceramic reactors are presented in the article as well. 相似文献
106.
107.
108.
Untersuchungen zum Vorkommen polycyclischer Moschus-Duftstoffe in verschiedenen Umweltkompartimenten
Hans -Dietrich Eschke Heinz -Jürgen Dibowski Josef Traud 《Environmental Sciences Europe》1995,7(3):131-138
In addition to the three compounds discussed in our first communication (UWSF 6/4, 183–189, 1994) this paper mentions another four substances from the group of the polycyclic musk flavors analysed in a number of detergents and cosmetics, in surface waters, in waste waters from municipal sewage treatment plants and in fish. These four substances are: 6-acetyl-1,1,2,3,3,5-hexamethylindane (AHMI, known for instance under the trade name Phantolide®), 6,7-dihydro-1,1,2,3,3-pentamethyl-4 (5H)-indanone (DPMI, known for instance under the trade name Cashmeran®), 7-acetyl-1,1,4,4-tetramethyl-6-ethyltetraline (ATTN, known for instance under the trade name Versalide®) and 5-acetyl-1,1,2,6-tetramethyl-3-isopropylindane (ATII, known for instance under the trade name Traseolide®). The results of these analyses show that except for ATTN, the manufacture of which was discontinued some ten years ago, these substances are considered to have an ubiquitous distribution in surface waters. This pollution evidently comes from the use of these flavors in various detergents and cosmetics, from where they enter surface waters via the waste waters from municipal sewage treatment plants. Choosing the Ruhr river as an example, the authors demonstrate that the pollution level is constant and that — due to their lipophilic nature — the compounds accumulate in fish leading to concentrations which markedly exceed those known, e.g., for nitromusk flavors in environmental samples. Two of the main contaminants are HHCB and AHTN, which have the highest concentrations both in the detergents analyzed and in environmental samples. 相似文献
109.
Ultrastructural and chemical characterization of egg surface of honeybee worker and queen-laid eggs 总被引:3,自引:0,他引:3
Tamar?Katzav-GozanskyEmail author Victoria?Soroker Josef?Kamer Claudia?M.?Schulz Wittko?Francke Abraham?Hefetz 《Chemoecology》2003,13(3):129-134
Summary. Worker policing in honeybees predicts the
evolution of a mechanism to discriminate between queenand
worker-born eggs. Although it has been postulated that
this discrimination is based on an egg recognition
pheromone, neither the chemistry nor the glandular source
were elucidated. To verify whether egg discrimination might
be based on structural differences, we compared the ultrastructure
surface of queen-laid diploid and haploid eggs to
that of worker-laid eggs using SEM. Only small differences
between the different types of eggs were found. Thus, at
least based on the fine structure of the egg surface, queen
eggs are indistinguishable from worker-laid eggs.To explore the chemosensory hypothesis for egg discrimination,
we conducted a detailed comparative chemical
analysis of the different egg types. The coating of all egg
types was dominated by linear alkanes, but queen eggs,
diploid and haploid, differed from those of workers on two
accounts: 1. The diversity of compounds found on queenlaid
eggs was much greater than found on worker-laid eggs,
mainly due to the number of hydrocarbons. 2. Acetates of
some fatty alcohols, alkenes and especially monomethylalkanes
were characteristic to queen eggs. The origin of the
two latter substances and the acetates is still unknown.
Whether these compounds constitute the signal that enables
police workers to discriminate between queen- and workerborn
eggs remains to be investigated. 相似文献
110.