Alkyd-amino resins based on waste PET for coating applications

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.     

CO2 dispersion around two PWR nuclear power plants in Brazil

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).     

Heterogeneous light-induced ozone processing on the organic coatings in the atmosphere

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.     

Ammonia emissions from naturally ventilated dairy cattle buildings and outdoor concrete yards in Portugal

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.     

Air pollution impacts of speed limitation measures in large cities: The need for improving traffic data in a metropolitan area

Assessing the effects of air quality management strategies in urban areas is a major concern worldwide because of the large impacts on health caused by the exposure to air pollution. In this sense, this work analyses the changes in urban air quality due to the introduction of a maximum speed limit to 80 km h^?1 on motorways in a large city by using a novel methodology combining traffic assimilation data and modelling systems implemented in a supercomputing facility. Albeit the methodology has been non-specifically developed and can be extrapolated to any large city or megacity, the case study of Barcelona is presented here. Hourly simulations take into account the entire year 2008 (when the 80 km h^?1 limit has been introduced) vs. the traffic conditions for the year 2007. The data has been assimilated in an emission model, which considers hourly variable speeds and hourly traffic intensity in the affected area, taken from long-term measurement campaigns for the aforementioned years; it also permits to take into account the traffic congestion effect. Overall, the emissions are reduced up to 4%; however the local effects of this reduction achieve an important impact for the adjacent area to the roadways, reaching 11%. In this sense, the speed limitation effects assessed represent enhancements in air quality levels (5–7%) of primary pollutants over the area, directly improving the welfare of 1.35 million inhabitants (over 41% of the population of the Metropolitan Area) and affecting 3.29 million dwellers who are potentially benefited from this strategy for air quality management (reducing 0.6% the mortality rates in the area).     

Bushmeat consumption and its implications for wildlife conservation in the semi-arid region of Brazil

Hunting plays an important socioeconomic role in the semi-arid region of Brazil, by supplying meat and other products. Nevertheless, there is a lack of information on which species are most used by the local populations and what are the implications for conservation of exploited animals. This paper explores the bushmeat consumption in the Brazilian Caatinga region, where wild animals comprise an important protein source. A questionnaire was used to gather information from hunters, and the consumption of bushmeat by their families was monitored. Interviews revealed that 58 vertebrate species could potentially be consumed as bushmeat, but the samples provided by the monitored families comprised only 28 species. Birds were the animals most consumed, followed by mammals, although the biomass of both groups was similar. The consumption of bushmeat was not correlated with hunters’ socioeconomic data (income, age or schooling). Hunters recognized that the populations of some game species appeared to be declining, showing that bushmeat consumption, together with the cultural, economic and social aspects of the human populations involved in hunting, should be considered when discussing the conservation of animal resources in the Caatinga region.     

Soil carbon stocks after conversion of Amazonian tropical forest to grazed pasture: importance of deep soil layers

Recent studies suggest that carbon (C) is stored in the topsoil of pastures established after deforestation. However, little is known about the long-term capacity of tropical pastures to sequester C in different soil layers after deforestation. Deep soil layers are generally not taken into consideration or are underestimated when C storage is calculated. Here we show that in French Guiana, the C stored in the deep soil layers contributes significantly to C stocks down to a depth of 100 cm and that C is sequestered in recalcitrant soil organic matter in the soil below a depth of 20 cm. The contribution of the 50–100 cm soil layer increased from 22 to 31 % with the age of the pasture. We show that long-term C sequestration in C4 tropical pastures is linked to the development of C3 species (legumes and shrubs), which increase both inputs of N into the ecosystem and the C:N ratio of soil organic matter. The deep soil under old pastures contained more C3 carbon than the native forest. If C sequestration in the deep soil is taken into account, our results suggest that the soil C stock in pastures in Amazonia would be higher with sustainable pasture management, in particular by promoting the development of legumes already in place and by introducing new species.     

Environmental Ethics: Driving Factors Beneath Behavior,Discourse and Decision-Making

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.