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121.
Nowadays, the world faces unprecedented challenges in social, environmental and economical dimensions, in which the industrial design has showed an important contribution with solutions that provide positive answers regarding these problems. In particular, due to its relevance, the automotive industry confronts a moment of crises, and based on the ecodesign of products it has been transforming the challenges in opportunities. In this context, the use of natural fiber composites, produced in developing countries, have presented several social, environmental and economical advantages to design “green” automotive components. Thus, this work through LCA method demonstrates the possibility to use natural fibers through a case study design which investigates the environmental improvements related to the replacement of glass fibers for natural jute fibers, to produce a structural frontal bonnet of an off-road vehicle (Buggy). Results pointed out the advantages of applying jute fiber composites in Buggy enclosures.  相似文献   
122.
The Brazilian program of payment for environmental services (PES) is based on ranges of potential erosion decrease (ED) from soil and water conservation proposals estimated from the Universal Soil Loss Equation. Changes in land use and land cover (LULC) result in many alterations of the basin water balance. Therefore, to contribute to the methodological development of Brazilian PES, this paper proposes a quantification of hydrological benefits based on conservation measures. We propose basing the PES program on adding the potential water storage increase (WSI) parameter estimated from the runoff curve number model. Two LULC change scenarios were run considering conservation measures on degraded areas. We found that indicators of ED and WSI were compatible tools for driving the eligibility of soil and water conservation measures. However, the water storage parameter seems to be better at managing the PES mechanism because it is based on water prices and can contribute to appreciation of the efforts performed by the rural producers. The use of the SCS-CN method presents greater feasibility as a tool for the implementation of PES programs in ungauged basins. Thus, an analysis of the success of the innovation proposal of the Brazilian PES program allows inferences to be made about the quantification and financial valuation of hydrological benefits of the potential storage increase and current water price.  相似文献   
123.
This report briefly presents the aims and the fields of interest of the Environmental and Cultural Heritage Division (Italian Chemical Society) and the issues addressed during its national congress, held in Rimini in June 2013. The broad range of topics raised by different speakers, the variety of affiliations and institutions participating at the conference, the scientific organisations and private companies co-sponsoring the different sessions give a clear picture of the interdisciplinarity which is a hallmark of this division.  相似文献   
124.
Indoor air quality in elementary schools of Lisbon in spring   总被引:1,自引:0,他引:1  
Analysis of indoor air quality (IAQ) in schools usually reveals higher levels of pollutants than in outdoor environments. The aims of this study are to measure indoor and outdoor concentrations of NO2, speciated volatile organic compounds (VOCs) and carbonyls at 14 elementary schools in Lisbon, Portugal. The investigation was carried out in May–June 2009. Three of the schools were selected to also measure comfort parameters, such as temperature and relative humidity, carbon dioxide (CO2), carbon monoxide (CO), total VOCs, and bacterial and fungal colony-forming units per cubic metre. Indoor concentrations of CO2 in the three main schools indicated inadequate classroom air exchange rates. The indoor/outdoor (I/O) NO2 ratio ranged between 0.36 and 0.95. At the three main schools, the total bacterial and fungal colony-forming units (CFU) in both indoor and outdoor air were above the advised maximum value of 500 CFU/m3 defined by Portuguese legislation. The aromatic compounds benzene, toluene, ethylbenzene and xylenes, followed by ethers, alcohols and terpenes, were usually the most abundant classes of VOCs. In general, the indoor total VOC concentrations were markedly higher than those observed outdoors. At all locations, indoor aldehyde levels were higher than those observed outdoors, particularly for formaldehyde. The inadequate ventilation observed likely favours accumulation of pollutants with additional indoor sources.  相似文献   
125.
Oceanographic processes play a significant role in shaping the genetic structure of marine populations, but it is less clear whether they affect genetic differentiation of highly mobile vertebrates. We used microsatellite markers and mtDNA control region sequences to investigate the spatial genetic structure of short-beaked common dolphins (Delphinus delphis) in southeastern Australia, a region characterised by complex oceanographic conditions associated with the East Australian Current (EAC). A total of 115 biopsy samples of dolphins were collected from six localities spanning approximately 1,000 km of the New South Wales (NSW) coastline. We found evidence for contrasting genetic diversity and fine-scale genetic structure, characterised by three genetically differentiated populations with varying levels of admixture. Spatial genetic structure was not explained by a model of isolation by distance, instead it coincides with main patterns of oceanographic variation along the EAC. We propose that common dolphins along the EAC may be adapted to three water masses recently characterised in this region.  相似文献   
126.
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.  相似文献   
127.
Little attention has been given to the behavioural and physiological effects of dredging on clams. The response of the clam Spisula solida under stress imposed by dredging activity is analysed in terms of reburial time and two acute indices: AEC (adenylic energetic charge) and ATP per milligram dry weight. Stress on undersized (<25 mm) S. solida, due to habitat disturbance by dredging itself and subsequent aerial exposure was measured with in situ studies during September 1999 at Vilamoura, a bivalve sandy ground, off the southern coast of Portugal. The study showed significant increases in reburial time and a decrease in adenylic-derived indices of stressed bivalves compared with in situ control bivalves monitored by SCUBA divers. It was concluded that the stress caused by dredging affects the behavioural and physiological responses of S. solida. Moreover, the reburial time is an easy and valuable indicator of stress levels in the studied clam.  相似文献   
128.
129.
Three blends formed by: (i) food processing waste (CP(FP)), (ii) waste water sewage sludge (CP(WW)), and (iii) their mixture (CP(FP+WW)), blended with tree pruning as bulking agent, were composted over 3 months. During composting the blends were monitored for the main physical-chemical characteristics: temperature, oxygen saturation level (O(2)%), pH, total and volatile solids, total organic carbon, and organic nitrogen (N(org)). In addition to the main parameters, the dissolved organic carbon (DOC), the inorganic nitrogen and the Oxygen Uptake Rate (OUR) were monitored. All the mixtures easily reached a peak temperature around 70°C, related to the lowest O(2)%. After 90 d, CP(FP), CP(FP+WW), and CP(WW) showed an organic matter mineralization of 43%, 35% and 33%, respectively; CP(FP) fitted an exponential model while both CP(FP+WW), and CP(WW) fitted a logistic model. During composting an OUR reduction of 79%, 78% and 73% was registered in CP(FP), CP(FP+WW), and CP(WW), respectively; the OUR successfully fitted the adopted exponential model and well reflected the stabilization process in time. The N(org) recovery at the end of the process was positive only in CP(WW) (11.6%). The DOC significantly decreased during the composting process but did not successfully fit any model. The mineral nitrogen did not follow the typical pattern with NH(4)(+) disappearance and NO(3)(-) accumulation. Strong NO(3)(-) losses were evident in all blends, while NH(4)(+) accumulations were detectable only in CP(FP), and CP(FP+WW). The NH(4)(+)/NO(3)(-) ratio did not satisfactorily reflect the composting process over time. The comparison of the first order (exponential) and logistic (sigmoidal) models applied to the OUR and OM course highlights the role of mineral nitrogen as limiting factor during composting of the more stabilized sludge.  相似文献   
130.
This study investigates the effects of several blends of gasoline and anhydrous ethanol on exhaust emission concentrations of carbon monoxide (CO), total hydrocarbons (HCs), and nitrogen oxides (NOx) from a small spark-ignited non-road engine (SSINRE). Tests were carried out for different air/fuel equivalence ratios as measured by lambda (λ). A 196 cm3 single-cylinder four-stroke engine-generator operating at a constant load of 2.0 kW was used; pollutant gas concentrations were measured with an automatic analyzer similar to those typically used in vehicle inspections. The results showed that as the ethanol content of the mixture increased the concentrations of CO, HCs, and NOx reduced by 15, 53, and 34%, respectively, for values of λ < 1 (rich mixture) and by 52, 31, and 16% for values of λ > 1 (lean mixture). Overall, addition of anhydrous ethanol to the gasoline helped to reduce emissions of the pollutant gases investigated, what contributes to photochemical smog reduction and quality of life in urban areas.  相似文献   
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