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311.
This work analyses the separate collection systems used in Spanish towns with between 5000 and 50,000 inhabitants. The study looks at the systems and their efficiency by means of the indicators fractioning rate, quality in container rate and separation rate. The results obtained are compared with those from a similar study conducted earlier that was applied to towns and cities with populations over 50,000. It can be concluded that the most widely implemented system in Spain involves the collection of mixed waste from kerbside bins and picking up paper/cardboard, glass and lightweight packaging from drop-off points. Findings show that the best system is the one that collects mixed waste, organic material and multiproduct waste door-to-door, and glass from drop-off points. The indicator separation rate made it possible to establish beta regression models to analyse the influence of the following logistic variables: inhabitants per point (people/pt), time (years) and frequency of collection (freq). From these models it can be seen that people/pt has a negative effect on all the fractions, while freq and years have a positive effect in the case of paper.  相似文献   
312.
In the present work, selected agroindustrial solid residues from Brazil – biosolids from meat processing wastewater treatment and mixture of sawdust with these biosolids; residues from apple and orange juice industries; sugarcane bagasse; açaí kernels (Euterpe oleracea) and rice husk – were characterised as solid fuels and an evaluation of their properties, including proximate and ultimate composition, energy content, thermal behaviour, composition and fusibility of the ashes was performed. The lower heating value of the biomasses ranged from 14.31 MJ kg?1 to 29.14 MJ kg?1, on a dry and ash free basis (daf), all presenting high volatile matter content, varying between 70.57 wt.% and 85.36 wt.% (daf) what improves the thermochemical conversion of the solids. The fouling and slagging tendency of the ashes was predicted based on the fuel ash composition and on the ash fusibility correlations proposed in the literature, which is important to the project and operation of biomass conversion systems. The potential for application of the Brazilian agroindustrial solid residues studied as alternative energy sources in thermochemical processes has been identified, especially concerning direct combustion for steam generation.  相似文献   
313.
314.
The economic success of feedstock recycling procedures for plastic wastes is increasingly demanding the conversion of the starting residue into more valuable chemicals. Thermal cracking of polyethylenes leads to the preparation of equimolar mixtures of n-paraffins and 1-alkenes within the C2–C100 range. These 1-olefins can be catalytically upgraded by selective oxidation processes to more valuable products (e.g., ketones and fatty acids) with different uses such as polar waxes, cetane improvers, varnishes, and printer inks. The results obtained on oxidation in a modified Wacker system of a model 1-olefin (1-dodecene) as well as of a distillate cut (C10–C25) of the product from the thermal cracking of urban polyethylene waste are described.  相似文献   
315.
Influence of lipid content of mussel on levels of organochlorine compounds (polychlorinated biphenyls [PCBs] and OC pesticides) has been studied. Mussel samples coming from three sites in Galicia coast (Northwestern, Spain), Moa?a and Cangas C from Ría de Vigo and Barallobre from Ría de Ferrol, collected monthly in the period from November 2000 to October 2001, have been analysed. Organochlorine compounds, PCBs (IUPAC nos. 31, 28, 52, 101, 118, 153, 105, 138, 156 and 180) and OC pesticides (pp'-DDE, op'-DDT, pp'-DDT, aldrin, isodrin and endrin) have been extracted by means of Soxhlet and determined by using gas chromatography (electron capture detector [ECD]) and gas chromatography-mass spectrometry. Statistical analysis has been performed using the SPSS statistical package. Few compounds were correlated with lipid content (Pearson product-moment correlation); for samples coming from Barallobre, only the individual PCBs 31, 28, 52 (tri- and tetrachlorinated biphenyls) and 180 (heptachlorinated biphenyl) presented a significant correlation; for Moa?a samples, two cyclodiene pesticides, endrin and isodrin, presented a slight significant correlation with lipid content. From these results, it is deduced that the normalization of the concentration of organochlorine compounds to the lipid content is not necessary, in this way, avoiding possible error sources associated to the analytical determination of the lipid contentor reproductive status of mussel. Multivariate techniques (PCA) have been employed in order to study spatial and temporal distribution patterns of organochlorine compounds. The great differences found in studied samples are mainly related to spatial distribution: separations between estuarine bays (samples coming from Ría de Vigo and Ría de Ferrol) and between rural and urban zones (samples coming from Moa?a and Cangas C and samples from Barallobre, respectively).  相似文献   
316.
Air Pollution Potential: Regional Study in Argentina   总被引:4,自引:0,他引:4  
/ Air pollution potential is a measure of the atmospheric conditions that are unable to transport and dilute pollutants into the air, independently of the existence of sources. This potential can be determined from two atmospheric parameters: mixing height and transport wind. In this paper a statistical analysis of the mixing height and transport wind, in order to determine the areas with high or poor atmospheric ventilation in Argentina, is presented. In order to achieve this, meteorological data registered during 1979-1982 at eight meteorological stations were used. Daily values of the maximum mixing height were calculated from observations of daily temperatures at different heights and maximum surface temperature. At the same time as the maximum mixing height, the values of the transport wind were determined from the surface windspeed and the characteristics of the ground in the surroundings of each meteorological station. The mean seasonal values for both parameters were obtained. Isopleths of the mean seasonal of the maximum mixing heights were drawn. The percentage of seasonal frequencies of poor ventilation conditions were calculated and the frequency isopleths were also drawn to determine areas with minor and major relative frequencies. It was found that the northeastern and central-eastern regions of Argentina had a high air pollution potential during the whole year. Unfavorable atmospheric ventilation conditions were also found in the central-western side of the country during the cold seasons (37.5% in autumn and 56.9% in winter). The region with the greatest atmospheric ventilation is located south of 40 degrees S, where the frequency of poor ventilation varies between 8.0% in summer and 10.8% in winter.  相似文献   
317.
While the literature over the last ten years has dealt with the implementation of quality, environmental and other management systems in terms of the interest aroused and results obtained, little has been written about organisational behaviour and the extent to which such standards have been adopted in the service sector. The present article explores these variables in the hotel industry, based on information collected from 403 hotels. The empirical analysis conducted evinces significant differences in behaviour and penetration between the service and manufacturing sectors, as well as between the implementation of management systems and the introduction of other business practices in the hotel industry. The results shed light on the importance of implementing certified management systems for conducting the hotel business.  相似文献   
318.
Methylmercury is an important source of environmental contamination and the central nervous system (CNS) is one of the main target organs. Methylmercury genotoxicity was already demonstrated in peripherical tissues but was never detected in the brain. Thus, the objective of this work was to verify its genotoxic effect using brain cell lines. Glioblastoma (U373) and neuroblastoma (B103) human cell lines were exposed to methylmercury (0-10 microM). By measuring cellular viability, concentrations inducing <20% of cellular death (P<0.05) were selected: 1 and 0.1 microM. To detect micronuclei, 200,000 cells were treated with methylmercury for 24 h, and then incubated with cytochalasin B (2 microg/ml) for 72 h (U373) or 48 h (B103). The binucleation index, frequency of micronucleated cells, micronucleation index, metaphasic index and index of nucleoplasmic bridges were determined. Statistical analysis showed indices and percentages significantly higher (P<0.05) in methylmercury-treated cells. Each cell line was shown to be differently sensitive to each biomarker of genotoxic damage, which seems to indicate the existence of different mechanisms of toxicity. This work demonstrates, for the first time, MeHg ability to provoke genotoxicity in cells of brain origin with relatively low levels of exposure.  相似文献   
319.
Objective: We investigate the use of the Functional Capacity Index (FCI) as a tool for establishing vehicle safety priorities by comparing the life year burden of injuries to the burden of fatality in frontal and side automotive crashes. We demonstrate FCI’s utility by investigating in detail the resulting disabling injuries and their life year costs.

Methods: We selected occupants in the 2000–2013 NASS-CDS database involved in frontal and side crashes, merged their injuries with FCI, and then used the merged data to estimate each occupant’s overall functional loss. Lifetime functional loss was assessed by combining this measure of impairment with the occupants’ expected future life spans, estimated from the Social Security Administration’s Actuarial Life Table.

Results: Frontal crashes produce a large number of disabling injuries, particularly to the lower extremities. In our population, these crashes are estimated to account for approximately 400,000 life years lost to disability in comparison with 500,000 life years lost to fatality. Victims of side crashes experienced a higher rate of fatality but a significantly lower rate of disabling injury (0.3 vs. 1.0%), resulting in approximately 370,000 life years lost to fatality versus 50,000 life years lost to disability.

Conclusions: The burden of disabling injuries to car crash survivors should be considered when setting vehicle safety design priorities. In frontal crashes this burden in life years is similar to the burden attributable to fatality.  相似文献   
320.
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