全文获取类型
收费全文 | 714篇 |
免费 | 5篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 10篇 |
废物处理 | 31篇 |
环保管理 | 62篇 |
综合类 | 150篇 |
基础理论 | 168篇 |
环境理论 | 4篇 |
污染及防治 | 230篇 |
评价与监测 | 38篇 |
社会与环境 | 35篇 |
出版年
2023年 | 7篇 |
2022年 | 8篇 |
2021年 | 10篇 |
2020年 | 10篇 |
2019年 | 4篇 |
2018年 | 24篇 |
2017年 | 14篇 |
2016年 | 13篇 |
2015年 | 17篇 |
2014年 | 23篇 |
2013年 | 52篇 |
2012年 | 25篇 |
2011年 | 54篇 |
2010年 | 31篇 |
2009年 | 43篇 |
2008年 | 34篇 |
2007年 | 44篇 |
2006年 | 33篇 |
2005年 | 22篇 |
2004年 | 35篇 |
2003年 | 23篇 |
2002年 | 27篇 |
2001年 | 15篇 |
2000年 | 11篇 |
1999年 | 6篇 |
1998年 | 16篇 |
1997年 | 3篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 6篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1981年 | 4篇 |
1978年 | 3篇 |
1974年 | 3篇 |
1965年 | 3篇 |
1963年 | 3篇 |
1962年 | 2篇 |
1961年 | 2篇 |
1960年 | 3篇 |
1959年 | 2篇 |
1958年 | 4篇 |
1957年 | 6篇 |
1956年 | 5篇 |
1955年 | 8篇 |
1943年 | 3篇 |
1922年 | 3篇 |
排序方式: 共有728条查询结果,搜索用时 15 毫秒
541.
542.
Andreas Horn 《Umweltwissenschaften und Schadstoff-Forschung》2005,17(3):189
VG?D Corner (Verband für Geo?kologie in Deutschland)
Von Mitgliedern für Mitglieder 2. Workshop-Tagung und Jahreshauptversammlung am 5./6.11.05 in Tübingen 相似文献543.
Manfred Niecke Andreas Krüger Peter Hauff Hermann Ellenberg Ralph Labes und Susanne Niecke 《Umweltwissenschaften und Schadstoff-Forschung》1998,10(1):3-14
Zusammenfassung Mit der Hamburger Protonenmikrosonde untersuchen wir den Quecksilbergehalt in Seeadlerfedern, die in Mecklenburg-Vorpommern
über Jahrzehnte gesammelt wurden. Anhand der Fundorte und Funddaten ist es m?glich, ein zeitliches und regional differenziertes
Bild der Quecksilberbelastung, die vorwiegend durch Hg-halrige Saargutbeizen in der Landwirtschaft verursacht wurden, zu erstellen.
Wir vergleichen die gefundenen Konzentrationen mit der ‘geogenen’ Grundbelastung, die an Federproben des vorigen Jahrhunderts
von Museumstieren ermittelt wurde.
相似文献
544.
Gerd Bauer Manfred Deistler Andreas Gleiß Emmanuel Glenck Thomas Matyus 《Environmental science and pollution research international》1997,4(2):105-112
Material Flow Analysis (MFA) has become an important instrument in environmental science and pollution research. In this paper, we look at the MFA problem as a particularly structured system identification problem. Special emphasis is given to the linear, static case, where we describe a procedure for reconciliating the flow measurements and for estimating the unmeasured flows and the transfer coefficients by taking into account a priori restrictions such as balance equations. 相似文献
545.
The concentrations of selected pesticides, of some of their degradation products and nitrophenols in rain were measured at two stations in Denmark in the period January 2000-July 2001. Forty compounds were quantified at least at one station during at least one sampling period. Additionally 17 compounds could be detected but not quantified, and 22 compounds could not be detected at all. The highest depositions of pesticides were observed for pendimethalin and desethylterbuthylazine, which is a degradation product of terbuthylazine. The deposition of the nitrophenols 2,4-dinitrophenol, DNOC, 3-methyl-4-nitrophenol was much higher than that of pesticides. The deposition of 2,4-dinitrophenol was e.g. up to a factor of 40 higher than that of pendimethalin. Atrazine, chloridazon, 2,4-D, dieldrin, disulfoton, fenitrothion, isoproturon, lenacil, metazachlor and propachlor were found in precipitation, although these pesticides are not allowed in Denmark. It can therefore be concluded that they came from abroad and have been transported over at least 60-80 km. For some of these compounds the transport distance is much longer. 相似文献
546.
Wierrani F Kubin A Loew HG Henry M Spängler B Bodner K Grünberger W Ebermann R Alth G 《Die Naturwissenschaften》2002,89(10):466-469
We report the development of a novel simple experimental method which allows the comparison of new photosensitizers based on their production of reactive oxygen species. A high-performance liquid chromatography (HPLC) assay permits the monitoring of several substances (sensitizer, reactant and oxidized end product) simultaneously on a single chromatogram. Photoreactions were monitored throughout their course by the HPLC assay surveying the sensitizers' efficiency of singlet oxygen production by the oxidative decomposition of luminol. Several photosensitizers were tested: Rose Bengal, Methylene Blue, Protoporphyrin IX, Photosan III, Photofrin, Hypericin and Pseudohypericin. Additionally, photoreactions were monitored by a standard pO2 detection system. The measurements of the two detection methods were strongly correlated. Rose Bengal proved to be the most efficient photosensitizer, clearly decreasing the luminol concentration and causing a corresponding increase in aminophthalic acid. Our experiments show that when factors necessary for photochemical reactions are absent or are blocked (antioxidants), no reaction can be detected. 相似文献
547.
548.
549.
Andreas H. W. Claass Dr. Wim J. Kleijer Otto P. Van Diggelen Eveline Van Der Veer Herman J. Sips 《黑龙江环境通报》1986,6(6):419-427
The potential value of microvillar enzymes in the prenatal diagnosis of cystic fibrosis (CF) has previously been demonstrated and is corroborated in the present comparative study. Maltase and alkaline phosphatase (ALP) activities were studied in the amniotic fluids of 57 pregnancies with a 1 in 4 risk for CF or with a known CF outcome and in 489 controls. A simple assay for maltase activity (MU-maltase) with the fluorogenic substate 4-methylumbelliferyl α-glucoside, offers great technical advantages and an at least equal detection rate of CF, when compared to the previously used test with maltose as substrate. Intestinal ALP was estimated either as phenylalanine inhibitable activity (PI-ALP) or as the proportions of residual activity in the presence of the inhibitors phenylalanine or homoarginine. MU-maltase and PI-ALP appeared the most successful methods: both tests were able to detect 14 of the 16 (88 per cent) pregnancies with fetal CF. Each of the two tests alone also allowed a correct prediction in 24 of the 25 pregnancies at risk but with normal outcome; however all 25 cases could be correctly predicted by a combined evaluation. It is suggested that more than one intestinal enzyme activity should be evaluated to allow optimal results in the prenatal monitoring of pregnancies at high risk for CF. 相似文献
550.
As hyperparasitoids may have a considerable influence on the control of herbivorous arthropods, analyzing the host-mediated impact of Bacillus thuringiensis-plants (Bt-plants) on hyperparasitoids is of interest. Laboratory-scale experiments were conducted in order to assess the potential effect of Bt-corn leaf material on the facultative hyperparasitoid Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae), mediated through the herbivore Chilo partellus Swinhoe (Lepidoptera: Crambidae) and its primary parasitoid Cotesia flavipes (Cameron) (Hymenoptera: Braconidae). In the Bt-group, significantly less C. flavipes larvae per host spun cocoons and pupated than in the control, and the mean fresh weight of a single C. flavipes cocoon was significantly reduced compared to the control. All C. flavipes cocoons of one host formed cocoon clusters. T. howardi females of the Bt-group parasitized significantly less cocoon clusters than in the control. Moreover, significantly fewer C. flavipes cocoons per cocoon cluster were successfully parasitized as compared to the control. As a consequence, T. howardi females of the control had more offspring than in the Bt-group. Adult female T. howardi offspring of the Bt-group weighed significantly less than in the control, but there was no significant weight difference between males of both groups. Our results suggest that transgenic insect-resistant plants could affect hyperparasitoids indirectly. However, it remains to be determined whether facultative hyperparasitoids prefer to develop as primary or secondary parasitoids under field conditions. 相似文献