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Tatiana Loureiro Rocio Macarena Moyano Dip Elizabete Lucas Luciana Spinelli 《Journal of Polymers and the Environment》2018,26(2):555-566
Cashew nut shell liquid (CNSL) is a byproduct of the cashew nut industry and consists predominantly of phenolic compounds that have an side chain with different degrees of unsaturation. Cardanol, one of these components, is biodegradable and widely available. Studies have revealed several polymerization reactions involving cardanol. However, the mechanisms and detailed structures of polymerization reactions have not been explored, although the final product shows different applications. In this work, we evaluated the mechanism and the products structure of the reaction of cardanol with: (i) boron trifluoride diethyl etherate (BF3O(CH2CH3)2), and (ii) formaldehyde. The characterizations were performed by FTIR, 1H NMR, SEC and TGA. The results show that the reaction of cardanol with aldehyde produces the expected like-comb structure with a long hydrocarbon pendent chain. Nevertheless, the reaction of cardanol with BF3O(CH2CH3)2 can exhibits a more complex structure since it was identified aromatic ring linkages, besides the expected polymerization through C=C. 相似文献
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Phytotoxicity to and uptake of enrofloxacin in crop plants 总被引:34,自引:0,他引:34
Phytotoxicity of enrofloxacin on crop plants Cucumis sativus, Lactuca sativa, Phaseolus vulgaris and Raphanus sativus was determined in a laboratory model: the effect of 50, 100 and 5000 microgl(-1) were evaluated after 30 days exposure by measuring post-germinative growth of primary root, hypocotyl, cotyledons and leaves. Concentrations between 50 and 5000 microgl(-1) induced both toxic effect and hormesis in plants, by significantly modifying both length of primary root, hypocotyl, cotyledons and the number/length of leaves. A toxic effect is induced by high concentration (5000 microgl(-1)), while hormesis occurs at low concentrations (50 and 100 microgl(-1)). A continuum between toxic effect and hormesis is found in the four plant species. Both toxic effect and hormesis can be related to an efficient plant drug uptake, in the order of microgg(-1). Plants are able to metabolize enrofloxacin into ciprofloxacin, as also happens in animals; Cucumis, Lactuca and Phaseolus biologically convert about one quarter of stored enrofloxacin. The ecological implication of enrofloxacin contamination in terrestrial environments is discussed. 相似文献
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F. Veloso-Gomes F. Taveira-Pinto Luciana das Neves Joaquim Pais Barbosa Carlos Coelho 《Journal of Coastal Conservation》2004,10(1):43-52
The entire northwestern coast of Portugal is undergoing severe erosion and there are several areas at high risk of erosion.
Commonly considered as a problem—because it jeopardizes human development along the coast—erosion is indeed a natural process
of sediment redistribution. This paper presents a brief analysis of erosion driving forces and the subsequent state of vulnerability
that coastal segments between the mouth of the River Douro and Cape Mondego are facing. The paper also discusses erosion risk
levels, low or high, and the subsequent questions whether there are populations, economical assets or natural habitats at
risk and/or areas prone to coastal flooding. Main challenges and future trends along the study area are identified in the
light of understanding the underlying causes of conflicts and what realistically can be achieved given the morphodynamics
and hydrodynamic processes, human development established along this coastal segment and the existing policies. 相似文献
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Sanders CJ Smoak JM Cable PH Patchineelam SR Sanders LM 《Journal of environmental radioactivity》2011,102(12):1122-1125
Total 210Pb and 7Be fallout rates were measured on the coastal region of Niteroi, Brazil. The monthly depositional flux of 210Pb and 7Be varied by a factor of 26, from 1.7 to 43.3 mBq cm−2 year−1 and ∼27, from 7.5 to 203.5 mBq cm−2 year−1, respectively. The relatively large oscillations in the depositional flux of 210Pb at this study site were likely due to variations in air mass sources, while the 7Be fluctuations may be driven by a combination of weather conditions. Local geology could support the periodic high fluxes of 210Pb from continental air masses, as shifting oceanic wind sources were affirmed by the uncorrelated 210Pb and 7Be fallout activities and 7Be/210Pb ratios. The 210Pb atmospheric deposition was found to be in agreement with local sediment inventories, an important consideration in geochemical studies that estimate sedimentation processes. 相似文献
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The net ecosystem carbon exchange of human-modified environments in the Australian Capital Region 总被引:2,自引:0,他引:2
Luciana Laura Porfirio Will Steffen Damian J. Barrett Sandra L. Berry 《Regional Environmental Change》2010,10(1):1-12
As part of a larger study to quantify and map ecosystem services in southeast Australia, we estimated carbon stored in biomass
and soils and the net ecosystem carbon exchange between the land surface and the atmosphere in the Australian Capital Region
(ACR). Our aim was to understand and quantify how different human-modified landscapes provide an essential ecosystem service:
the exchange and storage of carbon in the landscape. Using a remote sensing based modelling methodology, we obtained values
of Net Primary Productivity (NPP), total carbon in soil and biomass and carbon turnover from meteorological and terrain inputs
and vegetation attributes. We obtained a set of maps of NPP, total carbon (C) storage and C-turnover for the ACR. We superimposed
a land use/cover map to assign the uptake, storage and release of carbon to different land use/cover types. Our results support
the hypothesis that human-intensive land uses significantly affect the ability of terrestrial ecosystems to provide an important
ecosystem service in the form of carbon storage. 相似文献
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Luciana Migliore Stefania Paola De Filippis Davide Barchi Nicolino Rubattu 《Environmental pollution (Barking, Essex : 1987)》2010,158(1):129-134
Animal wastes from intensive pig farming as fertilizers may expose crops to antimicrobials. Zea mays cultivations were carried out on a virgin field, subjected to dressing with pig slurries contaminated at 15 mg L−1 of Oxy- and 5 mg L−1 of Chlor-tetracycline, and at 8 mg L−1 of Oxy and 3 mg L−1 of Chlor, respectively. Pot cultivation was performed outdoor (Oxy in the range 62.5-1000 ng g−1 dry soil) and plants harvested after 45 days. Tetracyclines analyses on soils and on field plants (roots, stalks, and leaves) did not determine the appreciable presence of tetracyclines. Residues were found in the 45-day pot corn only, in the range of 1-50 ng g−1 for Oxy in roots, accounting for a 5% carry-over rate, on average. Although no detectable residues in plants from on land cultivations, both experimental batches showed the same biphasic growth form corresponding to a dose/response hormetic curve. 相似文献
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Sergio Machado Corrêa Graciela Arbilla Eduardo Monteiro Martins Simone Lorena Quitério Claudinei de Souza Guimarães Luciana Vanni Gatti 《Atmospheric environment (Oxford, England : 1994)》2010,44(19):2302-2308
The fuel matrix used in Brazil is unique around the world. The intensive use of hydrated ethanol, gasohol (gasoline with 25% v/v of ethanol), compressed natural gas (CNG), and biodiesel leads to a peculiar composition of the urban atmosphere. From 1998 to 2002 an increase in formaldehyde levels was observed and since then, a reduction. This work presents a monitoring campaign that was executed from March 2004 to February 2009 by sampling at early morning on every sunny Wednesday for a total of 183 samples. The results indicate a strong reduction in formaldehyde levels from 2004 (average of 135.8 μg m?3 with SD 28.4 μg m?3) to 2009 (average of 49.3 μg m?3 with SD 27.4 μg m?3). The levels of acetaldehyde showed a slight reduction from 2004 (average of 34.9 μg m?3 with SD 8.0 μg m?3) to 2009 (average of 26.8 μg m?3 with SD 11.5 μg m?3). Comparing the results with the concurrent evolution of the fleet and of fuel composition indicates that the observed formaldehyde levels could be associated with the increase in ethanol use and in CNG use by engines with improved technology over the first converted CNG engines. Modelling studies using the OZIPR trajectory model and the SAPRC chemical mechanism indicate that formaldehyde is the main ozone precursor in Rio de Janeiro and acetaldehyde is the forth one. 相似文献
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Simões Marta Filipa Maiorano Alfredo Eduardo dos Santos Jonas Gomes Peixoto Luciana de Souza Rodrigo Fernando Brambilla Neto Almir Oliveira Brito António Guerreiro Ottoni Cristiane Angélica 《Environmental Chemistry Letters》2019,17(3):1413-1420
Environmental Chemistry Letters - The anthraquinone dye Remazol Brilliant Blue R is largely used in the textile industry. However, its removal from wastewaters is costly and complex. Many methods... 相似文献
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Beatriz Jabour Figueiraujo Vescovi Rosa Luciana Falci Theza Rodrigues Gilmar Simões de Oliveira Roberto da Gama Alves 《Environmental monitoring and assessment》2014,186(11):7771-7779
Considering the importance of benthic macroinvertebrates for diagnosis of variations in the ecological conditions of aquatic habitats, the aim of this study was to investigate the structure of the Chironomidae and Oligochaeta assemblages along an organic pollution gradient. The fauna specimens were obtained with the use of artificial substrates, and the environmental variables were recorded at five sites of the São Lourenço River, during 12 months. Metrics of the assemblage and detrended correspondence analysis were used to verify the response of the fauna to the pollution gradient. Procrustes analysis was used to verify whether the data on the Chironomidae and Oligochaeta assemblages, as well as the taxonomic and numerical resolution of these groups, provide similar results in relation to the pollution gradient. The richness, evenness, and taxonomic composition of the Chironomidae and Oligochaeta assemblages varied significantly among the collection sites, with distinct conservation conditions. Genera of the subfamilies Orthocladiinae and Tanypodinae were associated with the sites upstream of the urban area, where the dissolved oxygen levels are higher. Species of Oligochaeta and the genus Chironomus were associated with more organically polluted sites. No concordance was observed in the response of the Chironomidae and Oligochaeta assemblages in relation to the environmental variables, indicating the need to use both groups in biomonitoring studies. On the other hand, both the data on composition (presence or absence) and those on the lowest taxonomic resolution (abundance of subfamilies) were effective to diagnose the pollution gradient in the river studied. Therefore, when the environmental conditions along a river’s gradient are contrasting, we suggest the use of the lowest taxonomic resolution of Chironomidae and Oligochaeta in biomonitoring. That procedure considerably reduces the assessment time, besides being a method that can be used by people not specializing in the taxonomy of groups. 相似文献