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621.
The effects of hydrogen sulfide (H2S) diffusion into activated sludge (AS) on odor and volatile organic compound (VOC) concentrations in offgas were studied over an 8-week period. Most VOCs detected in the offgas of both aeration tanks were aromatic hydrocarbons. The VOC concentrations generally decreased when H2S was introduced to the AS compared with the control, indicating a negative effect of H2S on VOC removal. Two volatile organic sulfur compounds present in the test AS offgas showed an increase followed by a decrease during H2S peak loads. Six VOCs and odor concentration increased during the introduction of an H2S peak; however no correlation was observed between H2S and odor concentration. The increase in odor concentration resulted from the increase in the concentration of six aromatic VOCs, which had their removal slowed down during a 100-ppmv H2S peak. Activated sludge diffusion provides effective H2S removal with minimal affect on odor emissions.  相似文献   
622.
623.
This paper analyses the impact of the 2003 European heatwave on excessive human mortality in Portugal, a country that presents a relatively high level of exposure to heatwave events. A total of 2399 excessive deaths are estimated in continental Portugal, which implies an increase of 58% over the expected deaths. When these values are split by gender, it is seen that women increase (79%), was considerably higher than that recorded for men (41%). The increment of mortality due to this heatwave was detected for all the 18 districts of the country, but its magnitude was significantly higher in the inner districts close to the Spanish border. When we split by gender all districts reveal significant mortality increments for women, while the impact in men's excess deaths is not significant over 3 districts. Several temperature derived indices were used and evaluated in their capacity to explain, at the regional level, the excessive mortality (ratio between observed and expected deaths) by gender. It is shown that the best relationship is found for the total exceedance of extreme days, an index combining the length of the heatwave and its intensity. Both variables hold a linear relationship with r = 0.79 for women and a poorer adjustment (r = 0.50) for men. Additionally, availability of mortality data split by age also allowed obtaining detailed information on the structure of the population in risk, namely by showing that statistically significant increments are concentrated in the last three age classes (45–64, 65–74 and 75 or more). The use of air conditioning systems in some Portuguese hospitals had a major impact on the decrease (up to 40%) in excessive mortality values. A finer approach is relevant for prevention strategies, since it allows to identify better the target population of any preventive strategy regional and national authorities may be interested to implement.  相似文献   
624.
Having the objective of minimizing costs and improving their image in the consumer and export market, car battery industries began to seek environmental alternatives geared towards sustainable development. Reverse logistics flow represents an unprecedented tool for the economic and operational development of company activities, as well as a differential in the search for competitive advantages through environmentally correct practices. The aim of this paper is to describe the reverse logistics chain adopted by automotive battery industries in the midwest of the state of São Paulo, proposing a reverse logistics framework for small manufacturers that creates actions aimed at not harming the environment.  相似文献   
625.
The study looks into the occupational safety and working conditions among bus drivers in Metro Manila, the Philippines. Quantitative data were collected through survey interviews of 95 bus drivers using the stratified sampling technique. Results showed that bus drivers worked an average of 16?h/day and were engaged in risky driving behaviors such as over-speeding and road racing in order to reach their quota for the day. Fifty-nine percent experienced work-related accidents, with a mean of three accidents. The most common accident was hitting another vehicle followed by side swipe. The accidents were blamed on other drivers, followed by vehicle defect, inattentiveness and tiredness/micro-sleep or sudden involuntary sleep while driving. The most common health symptoms experienced by the bus drivers were fatigue, back pain, and cough and colds. This study underlines the need for an occupational health and safety program for bus drivers in the Philippines.  相似文献   
626.
Environment, Development and Sustainability - This paper evaluates compliance with environmental laws in the municipality of Sorriso and the impact of changing legislation on vegetation. To verify...  相似文献   
627.
Juvenile Dicentrarchus labrax L. (sea bass) were exposed to water diluted 17beta-estradiol (E2) (200 ng/L and 2000 ng/L) and treated with intraperitoneal (i.p) injection E2 (0.5 mg/kg and 5 mg/kg) during 10 days in order to study its genotoxicity and peroxidative damage, measured as gill, blood, liver and kidney DNA integrity decrease using DNA strand breaks assay as well as liver, gill and kidney lipid peroxidation (LPO) respectively. Juvenile sea bass gill DNA integrity was significantly decreased for all E2 exposure conditions. However, no differences were detected either between different exposure routes or tested concentrations. Blood DNA integrity was significantly decreased by E2 5 mg/kg as well as by both water diluted E2 exposure conditions. The highest E2 dose (5 mg/kg) also promoted liver DNA integrity decrease. Liver and gill LPO significantly increased at the highest E2 i.p treatment. An increasing trend of gill and liver LPO, though statistically insignificant, was observed in D. labrax exposed to water diluted E2 in both tested concentrations. The current results demonstrated that DNA damage in juvenile sea bass is affected by the E2 exposure conditions, such as water diluted E2 versus i.p E2 injection since i.p E2 injection promoted higher genotoxicity effect, in terms of affected organs than water diluted E2. Moreover, the organ sensitivity to E2 was different, since gill showed more susceptibility than blood, liver and kidney. Concerning kidney LPO and DNA integrity no differences were found between treated and controls juvenile sea bass groups.  相似文献   
628.
Current studies indicate a need to integrate environmental management with manufacturing strategy, including topics like cross-functional integration, environmental impact, and waste reduction. Nevertheless, such studies are relatively rare, existing still a need for research in specific regional contexts. At the same time, the results found are not unanimous. Due to these gaps, the objective of this article is to analyze if environmental management can be considered a new competitive priority for manufacturing enterprises located in Brazil. A cross-sectional survey was conducted with Brazilian companies certified by ISO 14001. Sixty-five valid questionnaires were analyzed through Structural Equation Modelling (SEM). The first conclusion is that environmental management presents a preventive approach in the sample analyzed, focused on eco-efficiency, what potentially do not to create a competitive advantage. This preventive approach inhibits environmental management from being regarded as a new competitive manufacturing priority, in the full sense as defined by the literature. Another important result is that environmental management, although following a preventive focus, may influence positively the four manufacturing priorities: cost, quality, flexibility and delivery.  相似文献   
629.
Guideline values are used to identify polluted or contaminated areas based on background values. Brazilian law establishes three guideline values for pollutants: a quality reference value (QRV), a prevention value, and an intervention value. Reference values refer to the natural concentration of an element or a substance in soils that have not been modified by anthropogenic impacts. These values inform assessments of soil quality and are used to establish maximum permissible limits. The objective of this study was to determine the natural levels and reference values for Cd, Co, Cr, Cu, Ni, Pb, and Zn in samples from the surface layer (0–20 cm) of 19 representative soils of the states of Mato Grosso and Rondônia, on Brazil’s agricultural frontier. Pseudo-total metal concentrations were obtained following microwave-assisted digestion using the aqua regia and EPA3051 methods. QRVs were calculated for each element as the 75th and 90th percentiles of the frequency distribution of the data. Natural levels of heavy metals in the soil samples followed the order: Cr?>?Zn?>?Cu?>?Co?>?Pb?>?Ni?>?and Cd (aqua regia) and Cr?>?Co?>?Cu?>?Pb?>?Zn?>?Ni?>?Cd (EPA3051). These values are generally lower than those reported in the Brazilian and international literature, which highlights the importance of establishing reference values for each state or for each soil type, taking into account the geomorphological, pedological, and geological diversity of the region under study.  相似文献   
630.
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