全文获取类型
收费全文 | 522篇 |
免费 | 3篇 |
国内免费 | 7篇 |
专业分类
安全科学 | 18篇 |
废物处理 | 18篇 |
环保管理 | 28篇 |
综合类 | 121篇 |
基础理论 | 122篇 |
环境理论 | 1篇 |
污染及防治 | 201篇 |
评价与监测 | 11篇 |
社会与环境 | 11篇 |
灾害及防治 | 1篇 |
出版年
2021年 | 3篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 11篇 |
2015年 | 10篇 |
2014年 | 7篇 |
2013年 | 21篇 |
2012年 | 25篇 |
2011年 | 17篇 |
2010年 | 17篇 |
2009年 | 25篇 |
2008年 | 23篇 |
2007年 | 29篇 |
2006年 | 17篇 |
2005年 | 18篇 |
2004年 | 14篇 |
2003年 | 19篇 |
2002年 | 13篇 |
2001年 | 20篇 |
2000年 | 28篇 |
1999年 | 27篇 |
1998年 | 19篇 |
1997年 | 17篇 |
1996年 | 7篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 10篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1990年 | 9篇 |
1988年 | 3篇 |
1981年 | 2篇 |
1979年 | 3篇 |
1972年 | 2篇 |
1970年 | 2篇 |
1969年 | 3篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1966年 | 5篇 |
1965年 | 5篇 |
1964年 | 3篇 |
1963年 | 4篇 |
1962年 | 5篇 |
1961年 | 2篇 |
1960年 | 8篇 |
1959年 | 4篇 |
1958年 | 2篇 |
1957年 | 2篇 |
1955年 | 5篇 |
排序方式: 共有532条查询结果,搜索用时 359 毫秒
121.
122.
Udo Muster Tom Schilling Harald Schobesberger Hertha Luttenberger Rolf Marr und Josef Draxler 《Umweltwissenschaften und Schadstoff-Forschung》1997,9(1):25-32
Zusammenfassung Bei einer genauen Kenntnis der vorliegenden Quecksilberverbindungen und ihrem Verhalten im Rauchgaspfad thermischer Anlagen
k?nnen durch entsprechende technische Ma?nahmen die Abscheideeffizienzen in trockenen, quasitrockenen und nassen Rauchgasreinigungsanlagen
erheblich gesteigert werden, so da? der derzeit gesetzlich vorgeschriebene Emissionsgrenzwert von 50 μg/m3 [i.N.tr.] eingehalten und unterschritten wird. Die in den letzten Jahren unternommenen Aktivit?ten und Fortschritte bei der
Reduzierung des Quecksilberaussto?es von thermischen Anlagen werden zusammenfassend dargestellt. Am Beispiel von tr?gerimmobilisierten
metall- und/oder metallsalzpartikelbelegten Tr?germaterialien (G/S-Reaktoren) wird die selektive Entfernung des Quecksilbers
bzw. dessen Verbindungen experimentell und theoretisch im Rauchgaspfad verdeutlicht. Aus der selektiven Abtrennung von Quecksilber
und seinen Verbindungen in der Gasphase resultieren auch entsprechende ?kologische und ?konomische Vorteile, die den allgemein
erkennbaren Trend der artspezifischen Abtrennung von Schadstoffen mit einer m?glichen Rückführung des Wertstoffes Quecksilber
in den Wirtschaftskreislauf unterstützen.
相似文献
123.
124.
Strategic investment in reputation 总被引:1,自引:0,他引:1
Dirk?SemmannEmail author Hans-Jürgen?Krambeck Manfred?Milinski 《Behavioral ecology and sociobiology》2004,56(3):248-252
Although collective efforts are common in both animal and human societies, many human and probably animal social dilemmas have no obvious cooperative solution, which is a challenge for evolutionary biologists. In public goods games, i.e. the experimental paradigm for studying the sustainability of a public resource with human subjects, initial cooperation usually declines quickly. Recently, it has been shown that the interaction with another social game in which good reputation attracts help, can maintain a high level of cooperation in the public goods game. Here we show experimentally that humans use different strategies in the public goods game conditional on whether the player knows that his decisions will be either known or unknown in another social game. The knowledge of being recognized as the same individual in both scenarios motivates players to invest in their reputation and thus sustain the public resource. However, cooperation declines immediately when individual identities switch from being recognizable to being unrecognizable between the two interacting games.Communicated by M. Borgerhoff-Mulder 相似文献
125.
126.
127.
128.
Many studies have examined differences in avian community composition between urban and rural habitats, but few, if any, have looked at nesting success of urban shrubland birds in a replicated fashion while controlling for habitat. We tested factors affecting nest survival, parasitism by the Brown-headed Cowbird (Molothrus ater), and species abundance in shrubland habitat in rural and urban landscapes. We found no support for our hypothesis that nest survival was lower in urban landscapes, but strong support for the hypothesis that survival increased with nest height. We found strong support for our hypothesis that cowbird parasitism was greater in urban than rural landscapes; parasitism in urban sites was at least twice that of rural sites. We found strong support for an urban landscape effect on abundance for several species; Northern Cardinal (Cardinalis cardinalis) and Brown-headed Cowbirds were more abundant in urban landscapes, whereas Field Sparrow (Spizella pusilla) and Blue-winged Warbler (Vermivora pinus) were more abundant in rural sites. There was support for lower abundances of Blue-gray Gnatcatcher (Polioptila caerulea) and Indigo Bunting (Passerina cyanea) with increased housing density. For six other species, edge and trail density or vegetation parameters best explained abundance. Lower abundances and greater parasitism in habitat patches in urban landscapes are evidence that, for some species, these urban landscapes do not fulfill the same role as comparable habitats in rural landscapes. Regional bird conservation planning and local habitat management in urban landscapes may need to consider these effects in efforts to sustain bird populations at regional and local scales. 相似文献
129.
Nataliya Voloshchuk Mona Knop Thomas Colby Erich Kombrink Lothar Hennig Diana Hofmann Dieter Sicker Andrej Gryganski Margot Schulz 《Chemoecology》2007,17(1):1-12
Summary. Doratomyces stemonitis (Hyphomycetales, Dematiaceae) is a saprotrophic fungus belonging to the mycobiota of the cereal rhizosphere. The fungus is
able to metabolize benzoxazolin-2-(3H)-one and a variety of its derivatives including higher plant detoxification products, microbial degradation products and
the chemically rather stable 2-amino-(3H)-phenoxazin-3-one. D. stemonitis can use all of these compounds as sole C-sources but their utilization, especially that of microbial degradation products
and 2-amino-(3H)-phenoxazin-3-one, seems to be highly energy consuming, resulting in slow mycelium growth and a change of colony morphology.
Benzoxazolin-2-(3H)-one derived compounds induce the synthesis of different isoforms of a glycosylated protein with sequence homologies to the
endo-1,3-β-glucanase Asp f2, an allergen from Aspergillus fumigatus and other Asp f2-like proteins e.g., from Verticillium dahliae or PRA1 antigen from Candida albicans. The induction of the protein is regarded as a stress response. 相似文献
130.
Nonribosomal peptides and polyketides represent a large class of natural products that show an extreme structural diversity and broad pharmacological relevance. They are synthesized from simple building blocks such as amino or carboxy acids and malonate derivatives on multimodular enzymes called nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), respectively. Although utilizing different substrates, NRPSs and PKSs show striking similarities in the modular architecture of their catalytic domains and product assembly-line mechanism. Among these compounds are well known antibiotics (penicillin, vancomycin and erythromycin) as well as potent immunosuppressive agents (cyclosporin, rapamycin and FK 506). This review focuses on the modular organization of NRPSs, PKSs and mixed NRPS/PKS systems and how modules and domains that build up the biosynthetic templates can be exploited for the rational design of recombinant enzymes capable of synthesizing novel compounds. 相似文献