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841.
842.
A. Garcia-Maraver D. Salvachúa M.J. Martínez L.F. Diaz M. Zamorano 《Waste management (New York, N.Y.)》2013,33(11):2245-2249
The heterogeneity of biomass makes it difficult if not impossible to make sweeping generalizations concerning thermochemical treatment systems and the optimal equipment to be used in them. Chemical differences in the structural components of the biomass (cellulose, hemicellulose, and lignin) have a direct impact on its chemical reactivity. The aim of this research was to study the influence of the organic components of the raw material from olive trees (leaves, pruning residues, and wood) in the combustion behavior of this biomass, as well as to find the component responsible for the higher ash content of olive leaves. Accordingly, the study used a thermogravimetric analyzer to monitor the different states and complex transitions that occurred in the biomass as the temperature varied. The decomposition rates of the different samples were analyzed in order to establish a link between each combustion phase and the composition of the raw materials. Two methods were used to determine the hemicellulose and cellulose contents of biomass from olive trees. Significant differences among the results obtained by the different methods were observed, as well as important variations regarding the chemical composition and consequently the thermal behavior of the raw materials tested. 相似文献
843.
R. del Valle-Zermeño J. Formosa J.M. Chimenos M. Martínez A.I. Fernández 《Waste management (New York, N.Y.)》2013,33(3):621-627
The main goal of this paper is to obtain a granular material formulated with Municipal Solid Waste Incineration (MSWI) bottom ash (BA) and air pollution control (APC) fly ash to be used as secondary building material. Previously, an optimum concrete mixture using both MSWI residues as aggregates was formulated. A compromise between the environmental behavior whilst maximizing the reuse of APC fly ash was considered and assessed. Unconfined compressive strength and abrasion resistance values were measured in order to evaluate the mechanical properties. From these results, the granular mixture was not suited for certain applications owing to the high BA/APC fly ash content and low cement percentages used to reduce the costs of the final product. Nevertheless, the leaching test performed showed that the concentrations of all heavy metals were below the limits established by the current Catalan legislation for their reutilization. Therefore, the material studied might be mainly used in embankments, where high mechanical properties are not needed and environmental safety is assured. 相似文献
844.
Matías Salvo Andrés Lizasoain Matías Castells Viviana Bortagaray Sebastián Castro Rodney Colina Fernando Lopez Tort Matías Victoria 《Food and environmental virology》2018,10(2):193-200
Human bocavirus (HBoV) infections are related to respiratory and gastroenteric diseases. The aim of this study was to investigate the presence of HBoV in both sewage and surface waters in Uruguay. Sixty-eight sewage samples from the cities of Salto, Paysandú, Bella Unión, Fray Bentos, Treinta y Tres and Melo and 36 surface water samples from the cities of Salto, Florida and Santa Lucía were studied. HBoV was screened by multiplex qPCR for the detection of the four subtypes, followed by monoplex qPCRs for the independent quantification of each subtype. A qualitative PCR followed by DNA sequencing and phylogenetic analysis was carried out for molecular characterization of HBoV strains. HBoV was present in a high frequency (69%) in sewage and only one positive sample (3%) was found in surface water. Concerning sewage samples, HBoV1 was detected in 11 (23%) out of the 47 positives samples, with a mean concentration of 8.2 × 104 genomic copies/Liter (gc/L), HBoV3 was detected in 35 (74%) of the positive samples with a mean concentration of 4.1 × 106 gc/L and subtypes 2 and/or 4 were detected in 39 (83%) of the positive samples with a mean concentration of 7.8 × 106 gc/L. After the phylogenetic analysis performed by a Bayesian approach, the four HBoV subtypes were confirmed. This is the first study determining a high frequency of HBoV and the presence of the four HBoV subtypes in aquatic matrices in Latin America, mainly in sewage. Although HBoV was scarcely detected in surface water, a waterborne transmission is likely to occur if people enter in contact with polluted surface waters for recreational activities such as fishing or swimming since an elevated frequency of HBoV was detected in raw sewage which is usually directly discharged into surface waters. 相似文献
845.
Elizabeth Vega Isidoro García David Apam M. Esther Ruíz Martha Barbiaux 《Journal of the Air & Waste Management Association (1995)》2013,63(4):524-529
Mexico City frequently experiences high levels of air pollution. This is due mainly to its topography and meteorology that suppress pollutant diffusion and dispersion. The atmospheric mixing is extremely poor, especially during the dry winter months. The levels of certain pollutants, such as particulate matter, are of concern since they have severe effects on public health. Visibility deterioration is one of the most noticeable effects in large cities. Biological effects of particulate matter on man and animals, ranging from mild eye irritation to death, have been reported. The effects depend on the size of the particles, their solubility, and toxicity. The main objective of this paper is to present the results of a chemical mass balance receptor model applied to a well-characterized data set of particulate matter collected in the Mexico City Metropolitan Area (MCMA). Samples of particulate matter were collected using a denuder and a Hi-Vol system for the respi-rable fraction and total suspended particles, respectively. In this paper the analysis of a database consisting of the chemical composition of 33 samples of respirable particulate matter (aerosols with diameter less than 2.5 µm) is presented. The 12-hour samples were acquired during day and night periods in a typical medium-income neighborhood from December 19, 1989 through February 5, 1990. 相似文献
846.
Anderson Martins de Souza Braz Antonio Rodrigues Fernandes José Roberto Ferreira Luís Reynaldo Ferracciú Alleoni 《Environmental science and pollution research international》2013,20(10):7231-7242
The solid-solution distribution or partition coefficient (Kd) is a measure of affinity of potentially toxic elements (PTE) for soil colloids. Kd plays a key role in several models for defining PTE guideline values in soils and for assessing environmental risks, and its value depends on edaphic and climatic conditions of the sites where the soils occur. This study quantified Kd values for Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn from representative soil samples from Brazil’s eastern Amazon region, which measures 1.2 million km2. The Kd values obtained were lower than those set by both international and Brazilian environmental agencies and were correlated with the pH, Fe and Mn oxide content, and cationic exchange capacity of the soils. The following order of decreasing affinity was observed: Pb?>?Cu?>?Hg?>?Cr?>?Cd?≈?Co?>?Ni?>?Zn. 相似文献
847.
S. Martínez-Lera J. Torrico J. Pallarés A. Gil 《Waste management (New York, N.Y.)》2013,33(7):1640-1647
The use of plastic bags and film packaging is very frequent in manifold sectors and film waste is usually present in different sources of municipal and industrial wastes. A significant part of it is not suitable for mechanical recycling but could be safely transformed into a valuable gas by means of thermal valorization. In this research, the gasification of film wastes has been experimentally investigated through experiments in a fluidized bed reactor of two reference polymers, polyethylene and polypropylene, and actual post-consumer film waste. After a complete experimental characterization of the three materials, several gasification experiments have been performed to analyze the influence of the fuel and of equivalence ratio on gas production and composition, on tar generation and on efficiency. The experiments prove that film waste and analogue polymer derived wastes can be successfully gasified in a fluidized bed reactor, yielding a gas with a higher heating value in a range from 3.6 to 5.6 MJ/m3 and cold gas efficiencies up to 60%. 相似文献
848.
Miroslava Kacániová Katarína Fatrcová-Sramková Janka Nozková Martin Melich Miriam Kadasi-Horáková Vladimíra Knazovická 《Journal of environmental science and health. Part. B》2013,48(1):92-96
The purpose of the study was to examine the antiradical activity of 11 natural honeys and to evaluate the antifungal properties of honey. Honey samples (10) were collected from different locations of Slovak Republic. Honeys were native to different plant species of Robinia pseudoacaccia, Brassica napus subs. napus, Castanea sativa Mill. Thymus serpyllum vulgaris and the other samples had multifloral origin. The low antiradical activitity in honey samples was determined. The best results were found in thyme honey from Rhodos (11.84 %) and Castanea honey from Nitra (10.61 %). The lowest antiradical activity was found in Acacia honey and determined to be 7.62 %. Statistically significant differences (P< 0.001) were found among thyme/Rhodos and Castanea/Nitra. The antifungal activities of honey samples were tested by 10 %, 25 % and 50 % (by mass per volume) concentration against fungi Penicillium crustosum, P. expansum, P. griseofulvum, P. raistrickii and P. verrucosum and by the agar well diffusion method. The solutions containing 10 % (by mass per volume) of honey did not have any effect on the growth of fungi. The strongest antifungal effect was shown by 50 % honey concentration against P. raistrickii. 相似文献
849.
de Medeiros Engelmann Pâmela dos Santos Victor Hugo Jacks Mendes Moser Letícia Isabela do Canto Bruzza Eduardo Barbieri Cristina Barazzetti Barela Pâmela Susin de Moraes Diogo Pompéu Augustin Adolpho Herbert Goudinho Flávio Soares Melo Clarissa Lovato Ketzer João Marcelo Medina Rodrigues Luiz Frederico 《Environmental science and pollution research international》2017,24(26):21398-21411
Environmental Science and Pollution Research - In Brazil, landfills are commonly used as a method for the final disposal of waste that is compliant with the legislation. This technique, however,... 相似文献
850.