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951.
Waste polyethylene terephthalate (PET) flakes were depolymerized by using propylene glycol (PG) in the presence of zinc acetate as catalyst. Glycolysis reaction products of waste PET obtained by using PET/glycol molar ratio 1/2. Two short oil alkyd resins of high acid values (30-40mgKOH/g) were prepared from phthalic anhydride (PA), glycerin (G), coconut oil fatty acids (COFA) and glycolyzed products of waste PET (PET-based alkyd resins) or glycols (PG) (reference alkyd resins). These alkyd resins were blended with 30%, 40%, and 50% of a commercial urea-formaldehyde, melamine-formaldehyde and urea-formaldehyde/melamine-formaldehyde mixture (1/1 weight ratio) and heated at 140 degrees C. The physical and chemical properties such as drying time, hardness, abrasion resistance, adhesion strength, water resistance, alkaline resistance, acid resistance, gelation time, and thermal oxidative degradation resistance (with thermogravimetric analysis, TGA) of these alkyd-amino resins were investigated. The properties of the waste PET-based resins were found to be compatible with the properties of the reference resins. 相似文献
952.
Cíntia Melazo Dias Kristina Stenström Igor Luiz Bacelar Leão Roberto Ventura Santos Iêda Gomes Nícoli Göran Skog Peter Ekström Rosangela da Silveira Corrêa 《Journal of environmental radioactivity》2009
Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental 14C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3 M NaOH solution. The trapped CO2 was analyzed for 14C by using a single stage accelerator mass spectrometry (SSAMS). 相似文献
953.
Sopheak Net Laura Nieto-Gligorovski Sašo Gligorovski Brice Temime-Rousell Stephane Barbati Yannis G. Lazarou Henri Wortham 《Atmospheric environment (Oxford, England : 1994)》2009,43(9):1683-1692
Many of the more recent studies concerning heterogeneous reactions of atmospheric interest, carry, in some cases, much more details but still follow the basic philosophy of the first pioneering studies. Therefore, in this study the accent is put on the additional complexities that arise when the aerosols of interest have more complex compositions. Hence, it is attempted to identify the products following the simultaneous ozone processing and light irradiation on particles coated with 4-phenoxyphenol in the presence of 4-carboxybenzophenone as a photosensitizer. In order to reveal a more complete picture on the fate of these aromatic compounds under controlled experimental conditions, different analytical tools such as gas chromatography coupled to mass spectrometry (GC–MS) and proton transfer reaction-mass spectrometry (PTR-MS) have been applied.Several surface bound products were identified via GC–MS and some of them (phenol, hydroquinone, catechol, 4-hydroxybenzoic acid, benzoic acid, fumaric acid, terephthalic acid, maleic acid, 1,2,4-trihydroxybenzene and 4,4′-oxydiphenol) confirmed with standards. The main volatile secondary products as identified by PTR-MS in this study were formic acid, phenol and p-benzoquinone.A reaction mechanism was proposed and density functional theory calculations were performed in order to elucidate the initial steps of the ozonolysis reaction on 4-phenoxyphenol in the presence of 4-carboxybenzophenone. 相似文献
954.
José Pereira Tom H. Misselbrook David R. Chadwick João Coutinho Henrique Trindade 《Atmospheric environment (Oxford, England : 1994)》2010,44(28):3413-3421
There is a lack of information on ammonia (NH3) emissions from cattle housing systems in Mediterranean countries, with most published data deriving from NW Europe. An investigation was carried out in NW Portugal to quantify NH3 emissions for the main types of dairy cattle buildings in Portugal, i.e. naturally ventilated buildings and outdoor concrete yards, and to derive robust emission factors (EFs) for these conditions and compare with EFs used elsewhere in Europe. Measurements were made throughout a 12-month period using the passive flux sampling method in the livestock buildings and the equilibrium concentration technique in outdoor yards.The mean NH3 emission factor for the whole housing system (buildings + outdoor yards) was 43.7 g NH3–N LU?1 day?1 and for outdoor concrete yards used by dairy cattle was 26.6 g NH3–N LU?1 day?1. Expressing NH3 emission in terms of the quantity of liquid milk produced gave similar values across the three dairy farms studied (with a mean of 2.3 kg N ton-milk?1 produced) and may have advantages when comparing different farming systems. In dairy houses with outdoor yards, NH3 emissions from the yard area contributed to 69–92% of total emissions from this housing system. Emissions were particularly important during spring and summer seasons from outdoor yards with NH3 emitted in this period accounting for about 72% of annual emissions from outdoor yards. Mean NH3 emission factors derived for this freestall housing system and outdoor concrete yards used by dairy cattle in Portugal were higher than those measured in northern Europe. In addition, values of animal N excretion estimated in this study were greater than official National standard values. If these emissions are typical for Portuguese dairy systems, then the current National inventory underestimates emissions from this source in NW of Portugal, because of the use of lower standard values of N excretion by dairy cattle. 相似文献
955.
João P. A. Fernandes N. Guiomar 《Journal of Agricultural and Environmental Ethics》2016,29(3):507-540
This paper tries to characterize the factors determining human relations with its environment and to identify the drives of those behavioral patterns and “praxis”. One scrutinizes the physiological and psychological factors that influence those drives, and tries to determine ways of overriding instinctive drives in favor of rational, sustainable ones. It focuses its attention on the way the different ecosystemic, economic and socio-cultural systems work, and pin-points the critical issues in view of the development of sustainable behavioral patterns. Also the values that must build the new behavioral paradigm, as well as the ways to ensure the evolutionary quantum-leap necessary to ensure this sustainable condition, and the fulfilment, at every level, the different needs of humans and human societies, are analyzed. In conclusion, it stresses the fact that any reliable and long lasting change towards a sustainable behavior must start at the individual and the close social groups levels, and of the development of new factors of self-fulfillment and gratification, able to support and foster that change. The proposed epistemological approach is particularly innovative, precisely because of this emphasis on the individual drives and the way they determine the global patterns of environmental use, as well as the way they can evolve into a more rational (human) character. In short, the paper focuses itself in the way man can evolve from its natural animal instincts and drives toward more rational ones, humanizing its behavior and turning, therefore, into an able actor of the process of sustainability building. 相似文献
956.
Valéria R. F. da Silva Sylvia F. Mitraud Maria L. C. P. Ferraz Eduardo H. S. M. Lima Maria Thereza D. Melo Armando J. B. Santos Augusto César C. D. da Silva Jaqueline C. de Castilhos Jamyle A. F. Batista Gustave G. Lopez Frederico Tognin João Carlos Thomé Cecília Baptistotte Berenice M. Gomes da Silva José Henrique Becker Juçara Wanderline Fernanda de Vasconcellos Pegas Gonzalo Róstan Guy Guagni dei Marcovaldi Maria Ângela G. dei Marcovaldi 《Environment, Development and Sustainability》2016,18(6):1541-1558
In the 35 years since its inception, the Brazilian National Program for the Conservation of Marine Turtles (TAMAR) has had great success in protecting the five species of sea turtles that occur in Brazil. It has also contributed significantly to worldwide scientific data and knowledge about these species’ biology, such as life cycles and migration patterns. TAMAR’s conservation strategies have always relied on a variety of environmental education and social inclusion (EESI) activities highly adapted to the socio-environmental evolving contexts of its 25 locations distributed across nine states. Diversity and flexibility are critical to enable timely and effective local responses to existing or potential threats to sea turtles. The intuitive, locally adapted, decentralized, and independent way EESI activities have been carried out have generated positive results in the resolution of specific and evolving local problems through the course of the project. This article brings EESI under the same conceptual framework that underlies its conservation approach by adopting an adaptive threat management framework to organize and qualify its educational and social inclusion interventions according to the main categories of threat addressed by TAMAR. 相似文献
957.
958.
Tina Elersek Sara Milavec Maša Korošec Polona Brezovsek Noelia Negreira Bozo Zonja Miren López de Alda Damià Barceló Ester Heath Janez Ščančar Metka Filipič 《Environmental science and pollution research international》2016,23(15):14780-14790
The residues of antineoplastic drugs are considered as new and emerging pollutants in aquatic environments. Recent experiments showed relatively high toxicity of 5-fluorouracil (5-FU), imatinib mesylate (IM), etoposide (ET) and cisplatin (CP) that are currently among most widely used antineoplastic drugs, against phytoplankton species. In this study, we investigated the toxic potential of the mixture of 5-FU?+?IM?+?ET against green alga Pseudokirchneriella subcapitata and cyanobacterium Synechococcus leopoliensis, and the stability and sorption of these drugs to algal cells. Toxic potential of the mixture was predicted by the concepts of ‘concentration addition’ and ‘independent action’ and compared to the experimentally determined toxicity. In both test species, the measured toxicity of the mixture was at effects concentrations EC10–EC50 higher than the predicted, whereas at higher effect concentration (EC90), it was lower. In general, P. subcapitata was more sensitive than S. leopoliensis. The stability studies of the tested drugs during the experiment showed that 5-FU, IM and CP are relatively stable, whereas in the cultures exposed to ET, two transformation products with the same mass as ET but different retention time were detected. The measurements of the cell-linked concentrations of the tested compounds after 72 h exposure indicated that except for CP (1.9 % of the initial concentration), these drugs are not adsorbed or absorbed by algal cells. The results of this study showed that in alga and cyanobacteria exposure to the mixture of 5-FU?+?ET?+?IM, in particular at low effect concentration range, caused additive or synergistic effect on growth inhibition, and they suggest that single compound toxicity data are not sufficient for the proper toxicity prediction for aquatic primary producers. 相似文献
959.
Annabel Fernandes João Coelho Lurdes Ciríaco Maria José Pacheco Ana Lopes 《Environmental science and pollution research international》2016,23(24):24614-24623
Boron-doped diamond (BDD) and Ti/Pt/PbO2 anodes were utilized to perform the electrodegradation of synthetic samples containing humic acid in the presence of different organic and inorganic carbon-containing and nitrogen-containing compounds. The influence of the chloride ion in the degradation process of the different synthetic samples was also assessed. The results showed that the anodic oxidation process can efficiently degrade recalcitrant compounds such as humic acid. The presence of carbonate in solution enhances the nitrogen removal, whereas it hinders the oxidation of the organic compounds. When organic nitrogen is present, it is converted to NH4 +, which in turn is oxidized to nitrate and to volatile nitrogen compounds. Hydroxyl radicals are more prone to oxidize the organic nitrogen than the ammonium nitrogen. The presence of chloride enhances the organic matter and nitrogen removal rates, BDD being the anode material that yields the highest removals. 相似文献
960.
Stephen G. Perz Liliana Cabrera Lucas Araújo Carvalho Jorge Castillo Rosmery Chacacanta Rosa E. Cossio Yeni Franco Solano Jeffrey Hoelle Leonor Mercedes Perales Israel Puerta Daniel Rojas Céspedes Ioav Rojas Camacho Ad?o Costa Silva 《Regional Environmental Change》2012,12(1):35-53
Initiatives for global economic integration increasingly prioritize new infrastructure in relatively remote regions. Such regions have relatively intact ecosystems and provide valuable ecosystem services, which has stimulated debates over the wisdom of new infrastructure. Most prior research on infrastructure impacts highlights economic benefits, ecological damage, or social conflicts. We suggest a more integrative approach to regional integration by appropriating the concepts of connectivity from transport geography and social?Cecological resilience from systems ecology. Connectivity offers a means of observing the degree of integration between locations, and social?Cecological resilience provides a framework to simultaneously consider multiple consequences of regional integration. Together, they offer a spatial analysis of resilience that considers multiple dimensions of infrastructure impacts. Our study case is the southwestern Amazon, a highly biodiverse region which is experiencing integration via paving of the Inter-Oceanic Highway. Specifically, we focus on the ??MAP?? region, a tri-national frontier where Bolivia, Brazil, and Peru meet and which differs in the extent of highway paving. We draw on a tri-national survey of more than 100 resource-dependent rural communities across the MAP frontier and employ indicators for multiple dimensions of connectivity and social?Cecological resilience. We pursue a comparative analysis among regions and subregions with differing degrees of community connectivity to markets in order to evaluate their social?Cecological resilience. The findings indicate that connectivity and resilience have a multifaceted relationship, such that greater community connectivity corresponds to greater resilience in some respects but not others. We conclude by noting how our findings integrate those from heretofore largely disparate literatures on infrastructure. The integration of transport geography with resilience thought thus stands to advance the study of infrastructure impacts. 相似文献