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801.
Jan Deprest Marie-Paule Emonds Jute Richter Philip DeKoninck Tim Van Mieghem Dominique Van Schoubroeck Roland Devlieger Luc De Catte Liesbeth Lewi 《黑龙江环境通报》2011,31(7):661-666
With the increased use of invasive fetal procedures, the number of women facing post-procedure membrane rupture is increasing. Here we review the use of platelets and fresh frozen plasma for sealing iatrogenic fetal membrane defects by describing the mechanisms of action of the amniopatch procedure as well as published experience. In cases of iatrogenic preterm pre-labour rupture of the membranes, amniopatch effectively seals the fetal membranes in over two-thirds of cases. There is a risk of 16% of in utero fetal death, which may occur at varying intervals from the procedure and often for unknown reasons. Amniopatch has also been used as a treatment of chorionic membrane separation. In summary, current experience suggests that in cases of early onset but persistent amniotic fluid leakage following an invasive fetal procedure, amniopatch is an option. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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804.
Large-scale patterns of shell variation in Littorina striata, a planktonic developing periwinkle from Macaronesia (Mollusca: Prosobranchia) 总被引:2,自引:1,他引:1
Littorina striata King and Broderip, 1832 is a strictly Macaronesian, intertidal periwinkle with planktonic development. The species displays
a high degree of shell variation involving size and sculpture (nodulose vs smooth shells). The present work provides a preliminary
account of some aspects of this shell variation on wave-exposed shores over the entire geographical range of the species.
Based on morphological patterns observed among other prosobranchs it was predicted that southern specimens of L. littorina should on the average be larger, heavier, more nodulose, and should show more shell repair marks, than northern specimens.
These expectations were confirmed for shell size and weight. In contrast, there was no consistent pattern in nodulosity between
archipelagos, even though there were differences at much smaller scales. Shell repair marks were more prevalent in northern
populations, but this trend was only due to a significant N–S difference among nodulose shells. This is surprising as nodulose
shells displayed significantly fewer shell repair marks than smooth shells. These observations were tentatively interpreted
as a function of presumed differential N–S patterns of wave action and ambient temperatures. In this context, wave action
in Macaronesia seems to increase in the south (contrary to what current theories predict). This atypical situation may confound
the interpretation of morphological patterns in L. striata so that firm conclusions cannot be drawn without further experimental work at different spatial scales. Nevertheless, it
seems that generalisations about macrogeographic shell morphology patterns, based on interspecific comparisons, are not directly
applicable to intraspecific patterns, and may strongly depend on local conditions which make adequate sampling and data treatment
very difficult.
Received: 10 September 1997 / Accepted: 15 January 1998 相似文献
805.
A. C. Engels L. Joyeux C. Brantner B. De Keersmaecker L. De Catte D. Baud J. Deprest T. Van Mieghem 《黑龙江环境通报》2016,36(3):266-273
The fetal central nervous system can already be examined in the first trimester of pregnancy. Acrania, alobar holoprosencephaly, cephaloceles, and spina bifida can confidently be diagnosed at that stage and should actively be looked for in every fetus undergoing first-trimester ultrasound. For some other conditions, such as vermian anomalies and agenesis of the corpus callosum, markers have been identified, but the diagnosis can only be confirmed in the second trimester of gestation. For these conditions, data on sensitivity and more importantly specificity and false positives are lacking, and one should therefore be aware not to falsely reassure or scare expecting parents based on first-trimester findings. This review summarizes the current knowledge of first-trimester neurosonography in the normal and abnormal fetus and gives an overview of which diseases can be diagnosed. © 2016 John Wiley & Sons, Ltd. 相似文献
806.
807.
M. Demarcke J.-F. Müller N. Schoon H. Van Langenhove J. Dewulf E. Joó K. Steppe M. Šimpraga B. Heinesch M. Aubinet C. Amelynck 《Atmospheric environment (Oxford, England : 1994)》2010,44(27):3261-3268
Monoterpenoid emissions from Fagus sylvatica L. trees have been measured at light- and temperature-controlled conditions in a growth chamber, using Proton Transfer Reaction Mass Spectrometry (PTR-MS) and the dynamic branch enclosure technique.De novo synthesized monoterpenoid Standard Emission Factors, obtained by applying the G97 algorithm (Guenther, 1997), varied between 2 and 32 μg gDW?1 h?1 and showed a strong decline in late August and September, probably due to senescence.The response of monoterpenoid emissions to temperature variations at a constant daily light pattern could be well reproduced with a modified version of the MEGAN algorithm (Guenther et al., 2006), with a typical dependence on the average temperature over the past five days.The diurnal emissions at constant temperature showed a typical hysteretic behaviour, which could also be adequately described with the modified MEGAN algorithm by taking into account a dependence on the average light levels experienced by the trees during the past 10–13 h.The impact of the past light and temperature conditions on the monoterpenoid emissions from F. sylvatica L. was found to be much stronger than assumed in previous algorithms.Since our experiments were conducted under low light intensity, future studies should aim at confirming and completing the proposed algorithm updates in sunny conditions and natural environments. 相似文献
808.
809.
Atmospheric polycyclic aromatic hydrocarbons in remote European and Atlantic sites located above the boundary mixing layer 总被引:1,自引:1,他引:0
Barend Leendert Van Drooge Pilar Fernández Joan O. Grimalt Evzen Stuchlík Carlos J. Torres García Emilio Cuevas 《Environmental science and pollution research international》2010,17(6):1207-1216
Background, aim and scope
Ambient air concentrations of polycyclic aromatic hydrocarbons (PAH) were determined at five elevated mountain sites on the European continent and the Atlantic Ocean. All sites can be considered remote background areas since they are situated above the timberline and they lack local emission sources of these compounds. 相似文献810.
O. Sracek M. Mihaljevič B. Kříbek V. Majer J. Filip A. Vaněk V. Penížek V. Ettler B. Mapani 《Environmental monitoring and assessment》2014,186(8):4891-4903
The mine tailings at Kombat, in semiarid northeastern Namibia, were investigated by the combination of solid-phase analyses, mineralogical methods, leaching tests, and speciation modeling. Dissolution of the most abundant primary sulfides, chalcopyrite and galena, released copper and lead which were adsorbed onto ferric oxyhydroxides or precipitated in the form of malachite, Cu2CO3(OH)2, and cerussite, PbCO3, respectively. Arsenic released from arsenopyrite was incorporated into ferric oxyhydroxides. Based on sequential extraction and 57Fe Mössbauer spectroscopy, a large amount of ferric iron is present as low solubility hematite and goethite formed rapidly (<10 years) under warm semiarid climatic conditions, and arsenic in these phases is relatively tightly bound. It seems that Cu and especially Pb in carbonate minerals represent a more serious environmental risk. Immobilization of As in hematite has implications for other mining sites in regions with similar climatic conditions because this process results in long-term immobilization of As. 相似文献