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71.
Albeit indirectly, through its lending and investing, the financial sector can contribute substantially to achieve sustainable development. One of such practices concerns investment on or financing of entities that deal with environmentally or socially sensitive transactions (gambling, tobacco, alcohol, arms, etc.). Although there is a wealth of literature on banks’ CSR and its reporting, one can count on the fingers of one hand the studies mentioning explicitly these issue. What is more, this CSR practice gets treated only cursorily in these few studies. This study focuses on the communication of information on investment and financing of firms from controversial sectors in banks’ sustainability reports. We begin by examining whether financial institutions in our sample report having such policies or not. Then, we investigate what kind of policies are reported. In addition, this study seeks to capture the influence of national culture and firm-specific characteristics (type of property, listing status and multinationality) on the reporting of such issues. Ordinal regression analysis is used to analyse the relation of these factors with such reporting. Our findings suggest that the disclosure of information on policies regarding investment on and financing of firms from controversial sectors is not widespread, and the organizations reporting policies of total exclusion of some sectors or projects on ethical grounds are few. This study may encourage more detailed analyses of the type of CSR policies examined and of their impacts. It also may be of utility to banks by raising awareness about the need to consider these issues.  相似文献   
72.
In this study, sugar cane residue or bagasse was used for removal of toxic metal ions from wastewater of an electroplating factory located in northeast Brazil. Prior acid treatment increased the adsorption efficacies in batch wise experiments. The microstructure of the material before and after the treatment was investigated by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Column operations showed that removals of Cu2+, Ni2+ and Zn2+ from wastewater (in the absence of cyanide) were 95.5%, 96.3.0%, and 97.1%, respectively. Regeneration of the adsorbent obtained in acid indicated that the efficiencies decreased only after the fourth cycle of re-use. Acid-treated sugar cane bagasse can be considered a viable alternative to common methods to remove toxic metal ions from aqueous effluents of electroplating industries.  相似文献   
73.
Sixty-four surface sediment samples and seven cored samples were collected from the partially closed bay of Jurujuba Sound, an inlet of Guanabara Bay in Southeast Brazil. Analysis of metals, including Pb, Zn, Ni, Cu and Cr, shows levels consistent with those typically found in urbanised and industrialised estuarine environments. Metal enrichment is concentrated around the inshore margin of the Sound and is significantly in excess of background, geological concentrations observed in basal muds from the seven cores. In the absence of industrialisation within the steep, but limited catchment that feeds into the Sound, the metal enrichment, particularly of Pb, Zn and Cu, is ascribed to the uncontrolled discharge of untreated sewage waste and urban surface runoff. This has increased markedly since the beginning of rapid urbanisation following the linking of the area by bridge to Rio de Janeiro in 1974.  相似文献   
74.
The Senegal sole, Solea senegalensis, is a species of flatfish that has several distinct cohorts of 0-group juveniles which use estuarine nurseries in summer and winter. The early cohort is more abundant and grows faster than the late cohort that stays in the nurseries during winter; however, climate warming may have an impact on the dynamics of this species’ juveniles. This study aimed to compare mortality, metabolic response and growth of S. senegalensis juveniles at different temperatures, reflecting present-day temperature (winter—12 °C; summer—24 °C) and future temperature (plus 3 °C) conditions, in estuarine nurseries in the southern European population. Mortality was low at 12 °C, being only 10 %, increasing to 30 % at 15 °C, 40 % at 24 °C and at 27 °C it hit 70 %. Metabolic rate increased steadily with increasing temperatures, yet it increased steeply from 24 to 27 °C. Thermal sensitivity was high for the temperature interval between 24 and 27 °C. Growth was very slow at 12 °C, at a rate of 0.03 mm day?1, increasing to 0.22 mm day?1 at 15 °C, and to 0.60 mm day?1, at 24 °C. However, at 27 °C growth rapidly declined to 0.12 mm day?1. Warming will be beneficial for the late cohort, resulting in a major increase in growth. However, the early cohort will not benefit from warming, due to high mortality and arrested growth, which clearly indicates that this species is under severe thermal stress at 27 °C. Thus, here we show, for the first time, that climate change may induce contrasting seasonal impacts on fish bio-ecology and physiology, namely in species with several cohorts over the course of the year. Phenotypic and/or genotypic plasticity may limit the impacts of climate change.  相似文献   
75.
Impact of sea-surface warming upon the fish assemblages of the Portuguese coast was assessed under two scenarios, the A2 and the B2 scenarios (Special Report on Emission Scenarios), which when coupled with a regional circulation model HadRM3 predict 1 and 2°C of sea-surface warming until the year 2100. Species richness increased in the Portuguese coast. In both scenarios, there was a latitudinal gradient in the amount of lost and gained species, increasing from north to south. An anomaly in the latitudinal gradient of species richness was detected in the southernmost area, which presented the lowest species richness of all areas, in the A2 scenario, and appears to be particularly vulnerable to climate change. Very few species were totally eliminated from Portuguese waters. For the Portuguese coast as a whole, there were more new than lost species, in both scenarios. Most of the new species were commercially important species, in the majority subtropical in the north and tropical in the south, mainly demersal and reef-associated. Reef-associated species also increased in relative importance. A commercial opportunity for fisheries may arise from climate warming, since most of the new species were commercial species and not many commercial species were lost. An increasing gradient from north to south was detected in the colonization of new species of herbivores, planktivores, and omnivores, as well as lower mean trophic level, which might have consequences for the future of trophic webs.  相似文献   
76.
Due to the current exploitation and consequent extinction of native medicinal plants around the world, new strategies have been proposed to address the sustainable use of this resource. Accordingly, the goal of this study is to assess the speed of bark regeneration of Myracrodruon urundeuva Allem?o and to compare the tannin content before and after tissue regeneration. Twenty individuals from an area of Caatinga in Caruaru, Pernambuco State (NE Brazil), were selected. To evaluate the speed of bark regeneration, four treatments were established, according to the area of bark removed (10 × 2, 6 × 5, 8 × 5 and 10 × 5 cm), with five replicates (five individuals of M. urundeuva Allem?o) and three treatments of tannin content (bark removed before damage, as regenerated tissue, and non-impacted bark or control). At the end of 23 months of monitoring the regeneration, we found that only seven of the 20 individuals analyzed did not fully heal. No significant correlation between the monthly percent regeneration and average monthly precipitation was found. The tannin content varied according to the quantified tissue (after damage, regenerated and control) as well as between damage classes (20 cm(2)-41.64 to 63.53 mg; 30 cm(2)-49.25 to 67.54 mg; 40 cm(2)-31.69 to 67.44 mg; 50 cm(2)-34.08 to 48.53 mg). Despite the variations found, there was no significant difference between the measurement periods (p > 0.05) or damage classes (p > 0.05). The results showed that the regeneration rate was higher in individuals belonging to the 10 × 2 and 10 × 5 cm groups and that there is no correlation between precipitation and regeneration speed. Tannin levels did not vary significantly in the tissues before damage and after regeneration.  相似文献   
77.
The impact of nanoparticles on fish health is still a matter of debate, since nanotechnology is quite recent. In this study, freshwater benthonic juvenile fish Prochilodus lineatus were exposed through water to three concentrations of TiO2 (0.1, 1, and 10 μg l?1) and ZnO (7, 70, and 700 μg l?1) nanoparticles, as well as to a mixture of both (TiO2 1 μg l?1?+?ZnO 70 μg l?1) for 5 and 30 days. Nanoparticle characterization revealed an increase of aggregate size in the function of concentration, but suspensions were generally stable. Fish mortality was high at subchronic exposure to 70 and 700 μg l?1 of ZnO. Nanoparticle exposure led to decreased acetylcholinesterase activity either in the muscle or in the brain, depending on particle composition (muscle—TiO2 10 μg l?1; brain—ZnO 7 and 700 μg l?1), and protein oxidative damage increased in the brain (ZnO 70 μg l?1) and gills (ZnO 70 μg l?1 and mixture) but not in the liver. Exposed fish had more frequent alterations in the liver (necrosis, vascular congestion, leukocyte infiltration, and basophilic foci) and gills (hyperplasia and epithelial damages, e.g., epithelial disorganization and epithelial loss) than the control fish. Thus, predicted concentrations of TiO2 and ZnO nanoparticles caused detectable effects on P. lineatus that may have important consequences to fish health. But, these effects are much more subtle than those usually reported in the scientific literature for high concentrations or doses of metal nanoparticles.  相似文献   
78.
Life Cycle Assessment (LCA) has been used to assess the environmental impacts associated with an activity or product life cycle. It has also been applied to assess the environmental performance related to waste management activities. This study analyses the packaging waste management system of a local public authority in Portugal. The operations of selective and refuse collection, sorting, recycling, landfilling and incineration of packaging waste were considered. The packaging waste management system in operation in 2010, which we called “Baseline” scenario, was compared with two hypothetical scenarios where all the packaging waste that was selectively collected in 2010 would undergo the refuse collection system and would be sent directly to incineration (called “Incineration” scenario) or to landfill (“Landfill” scenario). Overall, the results show that the “Baseline” scenario is more environmentally sound than the hypothetical scenarios.  相似文献   
79.
Automotive catalyst deactivation can be promoted by thermal and poisoning mechanisms. Catalyst efficiency is reduced by thermal degradation resulting in the agglomeration of precious metals and the reduction of the washcoat surface area. In this paper, the temperature influence on the commercial Pd/Rh-based automotive catalyst performance was studied. Textural and physicochemical characterisation techniques were employed, such as X-ray fluorescence (XRF), atomic absorption spectrometry (AAS), N2 physisorption, X-ray diffraction (XRD), temperature programmed reduction (TPR) and scanning electron microscopy coupled with energy-dispersive X-ray analysis (SEM–EDX). The catalysts were evaluated for CO and propane oxidation with a stoichiometric gas mixture similar to engine exhaust gas. The results indicated the transformation of alumina into high temperature phases and the formation of new mixed oxide phases. Evidence of sintered particles and several spots of palladium agglomerates was seen by SEM–EDX analysis. The activity results showed the effects of thermal deactivation on the conversion of the pollutants. In spite of exposure to extreme temperature conditions (72 h at 1200 °C), significant activity was still observed for carbon monoxide and propane oxidation reactions.  相似文献   
80.
Deinking by-products (DBP) have been used as alternative cover material for landfills and mine tailings. Since DBP is biodegradable because of its high cellulose and hemicellulose content, a laboratory experimental program was performed to monitor the evolution of biodegradation and changes in the physico-chemical and geotechnical properties of DBP samples submitted to accelerated biodegradation for 1460 days at 38 degrees C. The evolution of gas and leachate production was monitored in terms of both quality and quantity, which allowed for the calculation of mass loss with time. Under the conditions of the tests (no load applied), 19.6% of the mass was lost as gas, whereas 6.1% was leached out. The results show that biodegradation did not significantly alter the compaction behavior of DBP. The void ratio and water content increased significantly, while the volume of the samples slightly decreased. This seem to indicate that the porous structure of the samples was no longer the same after 1460 d of accelerated biodegradation. A slight increase in the relative density indicates that the organic/inorganic matter ratio increased. The results of permeability tests performed with samples at various stages of biodegradation and at various confining stresses show that the saturated hydraulic conductivity of recompacted biodegraded DBP decreased from 7 x 10(-7)cm/s to approximately 2 x 10(-7)cm/s, as biodegradation advanced.  相似文献   
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