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91.
Teresa Moura Carla Nunes Narcisa Bandarra Leonel Serrano Gordo Ivone Figueiredo 《Marine Biology》2011,158(2):401-412
The embryonic development and the level of dependency of the embryos from the maternal organism were investigated for Centroscymnus coelolepis. During the development, there is a 22–32% loss of organic matter and gains of 95–122% and 29–46% on moisture and inorganic
matter, respectively. Only 28–48% of the initial yolk energy is conserved in embryos, being the remaining used in catabolism.
In late pregnancy, the epithelium thickness of uterine villi decreases and vascularity increases. Results suggest that only
water and minerals are transferred from the mother to the embryos. Monounsaturated fatty acids are the main type of fatty
acids representing 48% of the total yolk fatty acid content, followed by polyunsaturated (30%) and saturated fatty acids (18–21%). 相似文献
92.
93.
Pegas PN Alves CA Evtyugina MG Nunes T Cerqueira M Franchi M Pio CA Almeida SM Verde SC Freitas MC 《Journal of environmental monitoring : JEM》2011,13(3):657-667
The aim of this study was to evaluate the indoor (I) and outdoor (O) levels of NO?, speciated volatile organic compounds (VOCs) and carbonyls at fourteen primary schools in Lisbon (Portugal) during spring, autumn and winter. Three of these schools were also selected to be monitored for comfort parameters, such as temperature and relative humidity, carbon dioxide (CO?), carbon monoxide (CO), total VOCs, and both bacterial and fungal colony-forming units per cubic metre. The concentration of CO? and bioaerosols greatly exceeded the acceptable maximum values of 1800 mg m?3 and 500 CFU m?3, respectively, in all seasons. Most of the assessed VOCs and carbonyls occurred at I/O ratios above unity in all seasons, thus showing the importance of indoor sources and building conditions in indoor air quality. However, it has been observed that higher indoor VOC concentrations occurred more often in the colder months, while carbonyl concentrations were higher in the warm months. In general, the I/O NO? ratios ranged between 0.35 and 1, never exceeding the unity. Some actions are suggested to improve the indoor air quality in Lisbon primary schools. 相似文献
94.
Marcos?R.?Moreira-Silva Carlos?A.?Tello?Sáenz Jo?o?O.?Rodrigues?Nunes Manoel?Godoy Marcos?F.?S.?TeixeiraEmail authorView authors OrcID profile 《Environmental Chemistry Letters》2017,15(3):481-488
The emission of radon gas in regions of geological faults, during the radioactive decay of uranium and thorium, results in the formation of lead isotopes 210Pb, 208Pb, 207Pb and 206Pb. As a consequence, the lead contamination in the soil poses a hazard to humans through ingestion of food, contaminated water, and even by direct contact with the soil contaminant. So far the relationship between the occurrence of geological faults and soil Pb contamination has not been established. Here, we studied lead in soils of regions with geological faults and their possible relationship with radon emissions. Soils were sampled from Presidente Prudente located in the far west of São Paulo State, Brazil. The region has strong evidence of the existence and direction of geological faults at depths of approximately 200 m. Soil sampling was done according to the USEPA 3050 method. Total lead was quantified by anodic stripping voltammetry. Results show that the total Pb concentration increases systematically with soil depth. This finding is explained by the fact that the lead originates from radon emissions. Pearson correlation analysis further proves a relationship of the nuclear track density obtained with CR-39 detectors, and mean Pb levels within each soil profile. Overall, our findings should improve risk evaluation of Pb contamination derived from radon emission and geological faults. 相似文献
95.
Fátima Lima Joana Portugal‐Pereira André F.P. Lucena Pedro Rochedo Jorge Cunha Manuel Lopes Nunes Alexandre Salem Szklo 《Natural resources forum》2015,39(3-4):175-190
This study estimated a series of indicators to assess the energy security of supply and global and local environmental impacts under different mitigation scenarios through 2050 in Brazil, designed with the integrated optimization energy system model MESSAGE‐BRAZIL. The assessment of interactions between environmental impacts and energy security dimensions was complemented through the application of life cycle assessment (LCA) methodology. Overall results imply energy security establishes more synergies than trade‐offs in increasingly stringent mitigation scenarios, especially patent within the sustainability dimension, which increases energy security and provides additional benefits regarding climate change mitigation and air pollution emissions. It is still necessary to extend analysis to other energy sectors in addition to the power supply sector and to promote a better understanding of repercussions of energy scenario expansion in energy security. 相似文献
96.
PCDD/Fs and dioxin-like PCBs in sediment and biota from the Mondego estuary (Portugal) 总被引:1,自引:0,他引:1
The concentrations of 17 polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in sediment and key species as an initial investigation on PCDD/Fs and dl-PCBs contamination in the Mondego estuary (Portugal). The results demonstrated that the values of the total PCDD/Fs (∑PCDD/Fs) concentrations were considerably lower than those of the sum of dl-PCBs (∑dl-PCBs) in all the studied samples. Regarding the contribution of individual congeners, OCDD was the predominant PCDD/F and the mono-ortho PCB 118 and PCB 105 were the dominant PCBs in the majority of the samples. Our results suggest that PCDD/Fs and PCBs behave quite differently along the aquatic food web: ∑PCDD/Fs concentrations were lower in higher trophic-level organisms with fish presenting a distinct PCDD/Fs congeners profile; on the contrary, the higher ∑dl-PCBs values were found in upper-level biota, although not exclusively, and quite similar dl-PCBs congener profiles were observed in nearly all the studied species. 相似文献
97.
Variations in embryo size and fatty acid (FA) dynamics during embryogenesis were evaluated in deep-sea pandalids and portunid
swimming crabs from the Portuguese continental margin and Madeira Island slope and compared with previous data on neritic
and deep-sea lobsters and shrimps (collected between February 2001 and March 2004). Inter-specific variations in embryo size
seem to be dictated primarily by phylogeny rather than by differences in reproductive or early life history traits. FA reserves
were significantly correlated with embryo size (P < 0.001). Principal component analysis revealed differences among three groups (1—neritic caridean shrimps, 2—deep-sea pandalids
of the genus Plesionika, and lobsters, 3—portunid crabs and the deep-sea pandalid Chlorotocus crassicornis, Costa 1871). Group 1 was clearly separated by PC1 mainly due to the higher percentage of essential C18 (linoleic and linolenic acids) and C20 (namely eicosapentaenoic) polyunsaturated FA (specific markers of primary producers). PC2 separated Group 2 from Group 3
due to differences in the percentage of several saturated FA (including odd-numbered FA—bacterial markers) and C18 monounsaturated FA (namely 18:1n − 9, a general marker of carnivory). Therefore, these differences among groups seem to result from distinctions in diet and
ecological niche. Intra-specific differences in FA composition between western and southern Plesionika martia martia (A. Milne-Edwards, 1883) populations may reflect higher water temperatures on the south sub-tropical coast. Lobster embryonic
development was more demanding of lipid energy than that of the other decapod species, which may reflect an evolutionary trend
in decapod taxa related to an increasing degree of lecithotrophy. However, a lower FA catabolism can be interpreted as an
enhanced independence of the newly hatched larvae from external energy sources. Higher FA content at hatching and, as a consequence,
a greater independence from the external environment should increase the chances of larval survival.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
98.
Landscape-fragmentation change due to recent agricultural expansion in the Brazilian Savanna,Western Bahia,Brazil 总被引:1,自引:0,他引:1
99.
Malacarne Ingra Tais De Souza Daniel Vitor Rosario Barbara Dos Anjos Viana Milena De Barros Pereira Camilo Dias Seabra Estadella Debora dos Santos Jean Nunes Ribeiro Daniel Araki 《Environmental science and pollution research international》2021,28(12):14285-14292
Environmental Science and Pollution Research - Crack-cocaine is a cocaine by-product widely consumed by general population in developing countries. The drug is low cost and is associated with more... 相似文献
100.
Fabíola Maria N. Nunes M.C.C. Veloso P.A. de P. Pereira J.B. de Andrade 《Atmospheric environment (Oxford, England : 1994)》2005,39(40):927
Biogenic emissions of volatile organic compounds (VOCs) play a fundamental role in atmospheric chemistry. Vegetation is the most abundant natural source of VOCs, while terpenoids, as limonene, α and β pinene and mircene, top the plants emission list. Much interest has been demonstrated in oxidation and photooxidation reactions of VOCs, particularly of monoterpenoids, owing to their diversity and to uncertainties regarding their mechanism of reaction. Quantification of primary carbonylic compounds, as well as of biradical reaction components, is highly relevant to the understanding of the major reactions. In this context, taking into account both structural factors and the fact that these compounds are found in the essential oils of plants typically found in Brazil and that they may be present in the atmosphere from emission by the plants, the monoterpenoids (S)-(+)-carvone, (R)-(−)-carvone, (−)-carveol, geraniol and citral (a mixture of the isomers geranial and neral) were selected for this study.The ozonolysis reactions of the monoterpenoids were carried out under dark conditions for all experiments, due to their photochemical reactivity. The analysis of the results lets us propose a mechanism by which these reactions occur. The observed results of the ozonolysis of S and R carvone suggest that the stereochemistry of asymmetric carbon does not affect either in the yields of both formaldehyde and of OH radicals produced in the reaction, or in the reactivity of these compounds, for which the rate constants were in the scale of 10−6 s−1.We found that, in the (−)-carveol's cis and trans mixture, even though the hydroxyl in the axial position—in the case of trans-(C) and cis-(D′) isomers—favors the attack by the ozone molecule on the external double bond, thus increasing the mixture's reactivity , it affects the average production of formaldehyde. The presence of geraniol and citral led to the production of formaldehyde, propanone, glyoxal, methyl–glyoxal and cyclohexanone (OH radicals) as reaction products. The influence of an electron attractor group bonded to the carbon of the double bond, on the reactivity of the double bond, could not be observed in the case of citral, due to strong interference occurring in the instrument in all experiments with this monoterpenoid. For this reason, only the kinetics of geraniol was monitored . 相似文献