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31.
Abstract

The presence of diethyl-phthalate (DEP), dibutyl-phthalate (DBP), butylbenzyl-phthalate (BBP), diethylhexyl-phthalate (DEHP) and diisononyl-phthalate (DINP) was determined in 295 tequila samples. They were grouped by age of maturation (white, aged, extra aged or ultra aged) and year of production (between 2013 and 2018). Gas Chromatography coupled with Mass Spectrometry was used for identification and quantification. The results showed that 65 samples (22% of the total) were phthalate free. DEP (0.13-0.27?mg/kg), BBP (0.05–2.91?mg/kg) and DINP (1.64–3.43?mg/kg) were detected in 11 (3.73%), 37 (12.54%) and 5 (1.69%) samples, respectively. But, these concentrations did not exceed the maximum permitted limits (MPL) of phthalates for alcoholic beverages. DBP (0.01–2.20?mg/kg) and DEHP (0.03–4.64?mg/kg) were detected in 96 (32.54%) and 224 (75.93%) samples, from them only 10 (3.39%) and 15 (5.08%) samples, respectively, exceeded the MPL for alcoholic beverages and they were few tequilas produced in the year 2014 or before. DEHP was the most frequent phthalate found in tequila and observed DEHP concentrations were 2-times higher in ultra aged tequilas compared to those in white tequilas. We concluded that all tequilas produced in 2015 and after, satisfied the international standards for these compounds.  相似文献   
32.
Identifying and characterising the factors that determine why a local authority opts for a particular way of managing its waste collection service is an important issue, warranting research interest in the field of municipal solid waste (MSW) management. This paper presents empirical evidence spanning a broad time horizon (2002–2010) showing that economic and political factors impact in different ways on the provision of waste management services. We examine five alternatives in this area, including public and private service delivery formulas and, within each field, individual and joint options. Our findings highlight the importance of the service cost and that of the various indicators of fiscal stress as determinant factors of management decisions regarding the provision of MSW management services.  相似文献   
33.
Thermotolerant coliform (TC) loadings were quantified for 49 catchments draining into the North and South Bays of Santa Catarina (SC, southeastern Brazil), an area known for its tourism and aquaculture. TC loadings were calculated based on flow measurements taken in 26 rivers. TC concentrations ere quantified based on surface water samples collected at 49 catchment outlets in 2012 and 2013. Median TC loads ranged from 3.7 × 103 to 6.8 × 108 MPN s?1. TC loadings in the catchments increased in proportion to increases in resident human population, population density and percentage of urbanised area. Catchments with more than 60% of area covered by wastewater collection and treatment systems had higher TC loads per person than catchments with less than 25%. Based on the study catchments, these results indicate that current sewerage infrastructure is ineffective in reducing contamination of faecal origin to surface waters. These findings have important implications for the management of microbiological health hazards in bathing, recreational and shellfish aquaculture waters in the North and South Bays of Santa Catarina Island.  相似文献   
34.
Activated (AC-PW) and non-activated (C-PW) carbonaceous materials were prepared from the Brazilian-pine fruit shell (Araucaria angustifolia) and tested as adsorbents for the removal of reactive orange 16 dye (RO-16) from aqueous effluents. The effects of shaking time, adsorbent dosage and pH on the adsorption capacity were studied. RO-16 uptake was favorable at pH values ranging from 2.0 to 3.0 and from 2.0 to 7.0 for C-PW and AC-PW, respectively. The contact time required to obtain the equilibrium using C-PW and AC-PW as adsorbents was 5 and 4 h at 298 K, respectively. The fractionary-order kinetic model provided the best fit to experimental data compared with other models. Equilibrium data were better fit to the Sips isotherm model using C-PW and AC-PW as adsorbents. The enthalpy and entropy of adsorption of RO-16 were obtained from adsorption experiments ranging from 298 to 323 K.  相似文献   
35.
This work is a part of a wider study involving the economic and environmental implications of managing construction and demolition waste (CDW), focused on the operation of a large scale CDW recycling plant. This plant, to be operated in the Lisbon Metropolitan Area (including the Setúbal peninsula), is analysed for a 60 year period, using primary energy consumption and CO2eq emission impact factors as environmental impact performance indicators.Simplified estimation methods are used to calculate industrial equipment incorporated, and the operation and transport related impacts. Material recycling – sorted materials sent to other industries, to act as input – is taken into account by discounting the impacts related to industrial processes no longer needed.This first part focuses on calculating the selected impact factors for a base case scenario (with a 350 tonnes/h installed capacity), while a sensitivity analysis is provided in part two. Overall, a 60 year global primary energy consumption of 71.4 thousand toe (tonne of oil equivalent) and a total CO2eq emission of 135.4 thousand tonnes are expected. Under this operating regime, around 563 thousand toe and 1465 thousand tonnes CO2eq could be prevented by replacing raw materials in several construction materials industries (e.g.: ferrous and non-ferrous metals, plastics, paper and cardboard).  相似文献   
36.
A considerable number of bird species carry feathers to their nests. Feathers’ presence in the nests has traditionally been explained by their insulating properties. Recently, however, it has been suggested that feathers carried to the nests by females of the spotted starling (Sturnus unicolor L.) could have an ornamental function based on their ultraviolet (300–400 nm) and human-visible longer wavelength (400–700 nm) coloration. In our population, 95.7% of feathers found inside next-boxes occupied by nesting starlings were rock dove fly feathers. Of these feathers, 82.7% were naturally positioned with their reverse side oriented toward the entrance hole and 42.4% of all found feathers were situated within the nest-cup. Here we experimentally assess the signaling function of ultraviolet coloration of feathers in nests of spotless starlings by providing nests with a number of pigeon flight feathers that were respectively treated on their obverse, reverse, both, or neither side with a UV blocker. Starlings placed 42.5% of the experimental feathers in the nest-cup irrespective of the UV block treatment. Orientation of feathers toward the entrance hole was not related with their ultraviolet radiation. However, feathers placed within the nest-cup were more likely found with their reverse side oriented toward the entrance hole confirming our correlative findings. These results suggest a minor role of ultraviolet coloration on feather location by spotless starlings.  相似文献   
37.
Environmental Science and Pollution Research - The order Odonata has been regularly used as an indicator of the ecosystem’s condition. The objective of this review was to analyze the...  相似文献   
38.
Environmental Science and Pollution Research - In this study, the photocatalytic degradation of four fungicides, myclobutanil, penconazole and difenoconazole (triazole compounds) and boscalid...  相似文献   
39.
Environmental Science and Pollution Research - In this work, the activated persulfate oxidation of ciprofloxacin (CIP) using a low-grade titanium ore under sunlight or simulated sunlight were...  相似文献   
40.
Environmental Science and Pollution Research - The process TiO2/PAC/UV-vis has been under study and compared with the isolated treatments of adsorption and photocatalysis determining possible...  相似文献   
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