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The Brazilian shift from a primarily rural to a more urban society has created major challenges that public policies must address. One of the most relevant challenges is deep social exclusion in urban areas, especially in terms of adequate housing and access to urban opportunities (e.g., jobs, housing, and services). In this context, land use and transport planning play a critical role in the sustainable development agenda. The work presented here analyses the accessibility of low‐income dwellings licenced under the Brazilian housing programme to the low‐income population. To evaluate the accessibility of the programme's target population, a case study was conducted in the city of Rio de Janeiro, where 58,000 homes licensed under the programme were analysed using GIS tools in terms of the present public transport network and the location of the homes. The amount of time it takes to access public transport on foot and the homes’ locations in relation to major urban opportunities were also analysed. Finally, the same analysis was performed for the future transport network, and the results of the two analyses were compared to identify the scope of the legacy generated by investments in preparation for the 2016 network.  相似文献   
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The Bio-oil was produced from the pyrolysis of agricultural wastes (Eucalyptus sawdust) and discarded soybean frying oil. The temperature of the pyrolysis system was initiated at 28°C and increased to 850°C. Atmospheric distillation of crude bio-oil was performed and a fraction at a temperature range 160–240°C (pyrolysis oil) was separated and subjected to GC-MS, 1H-NMR, TGA and FTIR analysis to identify the different properties and compounds present in pyrolysis oil. It was noticed that there was an abundance of oxygen and nitrogen containing compounds as well as other reactive species in pyrolysis oil. To reduce the amount of these species, the pyrolysis oil was subjected to hydrogenation in the presence of NiMo as a catalyst. After hydrogenation, the atmospheric distillation of hydrogenated bio-oil was performed and another fraction at temperature range 160–240°C (hydrogenated bio-oil) was separated and analyzed by the same techniques. It was noticed that during hydrogenation, more than 60% oxygenated and other reactive species were converted into hydrocarbons. Hydrogenated bio-oil showed very similar physico-chemical properties such as distillation curve, density, viscosity, freezing point, flash point, the presence of hydrocarbons and enthalpy of combustion as aviation kerosene also known as QAV-1.  相似文献   
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This paper describes the quantitative determination of F, Cl, Br, Cd and Pb in plastic materials. The concentration of the elements Cl, Br, Cd and Pb is first semiquantitatively measured by X‐ray fluorescence spectrometry (XRF) directly in the solid sample with a detection limit of approximately 10 μg/g. Afterwards, F and any of the other elements which exceed the limit values for materials which are disposable without special precautions are measured after the digestion of the material. The samples are digested either under pressure in an oxygen atmosphere for F, Cl and Br or under pressure with nitric acid for Cd and Pb. The digestion converts the halides to the anions which are measured potentiometrically (F, Br) or with ion chromatography (Cl). Cd and Pb are measured by graphite furnace atomic absorption spectrometry (GF‐AAS). The determination limits achieved are 20 μg/g for F and Br, 250 μg/g for Cl, 0.01 μg/g for Cd and 0.2 μg/g for Pb, all below the limit values set by current regulations in Switzerland.  相似文献   
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Vermetid reefs are among the most important bioconstructions in the Mediterranean Sea, with a distribution restricted to the warmest part of the basin. Their structure, and vertical and geographical distribution make them good biological indicators of changes in sea level and sea-surface temperature over the last two millennia.  相似文献   
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Italy is a country highly vulnerable to floods and landslides. The present study aims to investigate disaster preparedness and perception of flood risk in a group of people living in an alpine valley in the north of Italy. Four hundred seven adult residents in nine communities exposed to hydrogeological risk were interviewed by using a structured questionnaire. Participants were asked about the adoption of a set of protective behaviors that can prevent negative consequences of floods. Perception of flood risk was assessed by means of a one-dimensional scale that was developed and validated by the authors. Items included in this scale asked participants to estimate likelihood of occurrence of different flood consequences and to express feelings of worry associated to them. Socio-demographic and experiential information on respondents were also collected. Overall, results showed that most of respondents were fairly well prepared to deal with a future flood disaster. Correlational and regression analyses indicated that disaster preparedness was positively associated with risk perception. In accordance with literature, there was not a significant relation between likelihood judgments and adoption of protective behaviors, while feelings of worry were associated with disaster preparedness. Authors interpret their results in relation to the socio-environmental characteristics of the studied communities. Theoretical, empirical and practical implications of the findings are also discussed.  相似文献   
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Tire debris (TD) and its organic components were identified as a main source of PM10 atmospheric and water pollution. Because few data are available on the embryotoxic effects of TD organic components, the lethal and teratogenic potential of tire debris organic extract (TDOE) was evaluated using the frog embryo teratogenesis assay-Xenopus (FETAX), coupled with a histopathological screening of the survived larvae. From stage 8 to stage 47, Xenopus laevis embryos were exposed to TDOE at concentrations of 50, 80, 100, 120 and 140 mg/L. The results showed 50 mg/L TDOE to be the non-observable effect concentration (NOEC). TDOE mortality at 80 mg/L was significantly higher than the control, but did not increase further with higher concentrations. A good concentration-response was observed for percentages of malformed larva and from 80 mg/L on these percentages were significantly higher than the control. Therefore, probit analysis gave a 144.6 mg/L TC50. At 120 and 140 mg/L, many larvae were plurimalformed. The most frequent alterations observed were abnormal gut coiling, microphthalmia, monolateral anophthalmia, and narrowing eyes. The histological screening mainly revealed ocular malformations such as double retina, retina nervous cell layer coiling, and altered lens. Moreover severe vacuolisation and necrosis were scored in liver and axial musculature. These results strongly support the assumption that TDOE is a powerful teratogen for X. laevis.  相似文献   
50.
On February 27, 2010, the world’s sixth strongest earthquake on record (8.8 M w) and tsunami hit central Chile. We assess the response of the epibenthic macrofaunal community following this event in Coliumo Bay, one of the areas most affected by this mega-perturbation. The indicators of aggregate and compositional variability show that 3 years after this event, the community appears to have undergone the following dynamics: (1) At an inter-annual timescale, the community (both in density and biomass) shifted through different structures with apparent directionality; (2) Oceanographic and biological seasonality had a strong cyclical influence on the inter-annual community response; (3) There was spatial homogenization of the community over time (i.e., recovery of diversity), probably promoted by the ecological functionality of scavenger species (i.e., crab Cancer coronatus and snail Nassarius spp.) and by the proportional increase in non-dominant species; (4) Bathymetry and bottom dissolved oxygen also played significant roles in the spatial structure of this community; (5) Three years after the perturbation, total density and total community biomass were still considerably below those described under unperturbed conditions, mainly associated with the decrease in density and biomass of dominant species. Therefore, in spite of this apparent community compositional recovery, the aggregate variability currently remains below the levels reported prior to the effect of the mega-earthquake and tsunami. These results provide evidence that supports both the Cross-Scale Resilience Hypothesis and the Response Diversity Hypothesis.  相似文献   
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