85 research outputs found

    USE OF GEOPHYSICAL TECHNIQUES FOR ANALYSIS OF TRACE METALS IN A CEMETERY UNSATURATED SOIL ZONE: Utilização de técnicas geofísicas para análise de metais traço em zona de solo não saturado de cemitério

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    The purpose of this research was to apply two geophysical methods [Resistivity Imaging Technique (RI) and Inductive Electromagnetic Technique (EM-31)] to verify this tool‚Äôs efficiency in locating in subsurface contamination plumes and/or metal ions released by decomposition of corpses and their shells at Necr√≥pole Nossa Senhora Aparecida, Piedade, SP. This research was carried out from October 2015 to September 2016. In the first phase, we used the Resistivity Imaging technique and later we applied the electromagnetic technique. This period between one investigation and another was useful to verify if anomalies changed during that period. Results showed that localized anomalies did not move and that results of both methodologies were similar, considering limitations of each technique.A pesquisa objetivou a aplica√ß√£o de dois m√©todos geof√≠sicos [T√©cnica de Caminhamento El√©trico (CE) e T√©cnica Eletromagn√©tica Indutiva (EM-31)] com intu√≠do de verificar a efici√™ncia dessa ferramenta na localiza√ß√£o em subsuperf√≠cie de plumas de contamina√ß√£o e/ou √≠ons met√°licos liberados pela decomposi√ß√£o de cad√°veres e seus inv√≥lucros na Necr√≥pole Nossa Senhora Aparecida, Piedade, SP. A pesquisa foi efetuada no per√≠odo de outubro/2015 a setembro/2016, onde utilizamos na primeira fase a t√©cnica do caminhamento el√©trico e posteriormente aplicamos a t√©cnica eletromagn√©tica; esse per√≠odo entre uma investiga√ß√£o e outra, serviu para verificarmos se houve movimenta√ß√£o das anomalias no decorrer do tempo. Os resultados demonstraram que n√£o houve movimenta√ß√£o das anomalias localizadas assim como os resultados das duas metodologias foram semelhantes, levando-se em considera√ß√£o as limita√ß√Ķes de cada t√©cnica

    Influence of the applied organic load (OLR) on textile wastewater treatment using submerged anaerobic membrane bioreactors (SAMBR) in the presence of redox mediator and powdered activated carbon (PAC).

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    This paper evaluated the treatment of textile wastewater in submerged anaerobic membrane bioreactors (SAMBR) operated on a bench scale. Particularly, the influence of operational conditions, such as the applied organic rate (OLR) and the dilution factor (for toxicity attenuation) of the textile wastewater, was evaluated on color and organic matter removal. In addition, the effect of powdered activated carbon (PAC) on SAMBR-1 and the addition of yeast extract (source of the redox mediator riboflavin) were also investigated. The results showed that reducing the textile wastewater dilution factor from 10? (phase 1) to 4? (phase 2) and 0? (no dilution) decreased the COD and color removal efficiencies in both SAMBRs, probably due to an increase in the toxic load. Nevertheless, PAC adsorbed toxic compounds found in the textile wastewater and helped biomass acclimatization, which led to higher COD and color removal efficiencies in SAMBR-1. The presence of yeast extract enhanced color removal efficiencies 3-fold in both SAMBRs when they were fed with undiluted textile wastewater

    Anaerobic digestion of hemicellulose hydrolysate produced after hydrothermal pretreatment of sugarcane bagasse in UASB reactor.

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    In the context of a sugarcane biorefinery, sugarcane bagasse produced may be pretreated generating a solid and liquid fraction. The solid fractionmay be used for 2G bioethanol production,while the liquid fraction may be used to produce biogas through anaerobic digestion. The aimof this study consisted in evaluating the anaerobic digestion performance of hemicellulose hydrolysate produced after hydrothermal pretreatment of sugarcane bagasse. For this, hydrothermal pretreatmentwas assessed in a continuous upflowanaerobic sludge blanket (UASB) reactor operated at a hydraulic retention time (HRT) of 18.4 h. Process performance was investigated by varying the dilution of sugarcane bagasse hydrolysate with a solution containing xylose and the inlet organic loading rate (OLR). Experimental data showed that an increase in the proportion of hydrolysate in the feed resulted in better process performance for steps using 50% and 100% of real substrate. The best performance condition was achieved when increasing the organic loading rate (OLR) from 1.2 to 2.4 g COD/L?d, with an organic matter removal of 85.7%. During this period, the methane yield estimated by the COD removal would be 270 L CH4/kg COD.Nonetheless,when further increasing the OLR to 4.8 g COD/L?d, the CODremoval decreased to 74%, together with an increase in effluent concentrations of VFA (0.80 g COD/L) and furans (115.3 mg/L), which might have inhibited the process performance. On the whole, the results showed that anaerobic digestion of sugarcane bagasse hydrolysate was feasible and may improve the net energy generation in a bioethanol plant, while enabling utilization of the surplus sugarcane bagasse in a sustainable manner

    Pharmaceuticals oxidation by chlorine and byproducts formation in aqueous matrices in bench scale.

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    F?rmacos e desreguladores end?crinos s?o encontrados em ?guas naturais brasileiras, incluindo alguns mananciais de abastecimento, tamb?m em fun??o da baixa cobertura de coleta e tratamento de esgotos no Brasil. Nesse cen?rio, o presente trabalho intentou avaliar a remo??o de tr?s f?rmacos - sulfametoxazol (SMX), diclofenaco (DCF) e 17?-estradiol (E2) - em ?gua destilada por meio da oxida??o com cloro (hipoclorito de s?dio), variando-se a dose de cloro e o tempo de contato em ensaios de batelada. As solu??es cloradas foram analisadas, ainda, por cromatografia acoplada ? espectrometria de massas para identifica??o de eventuais subprodutos de oxida??o. Para tempo de contato de 10 min e dose de cloro de 1,5 mg.L-1, foi observada remo??o m?dia de 61% para DCF, 36% para E2 e 33% para SMX. Apenas para o DCF verificou-se diferen?a estatisticamente significativa (?=0,05) para dose de cloro de 3,0 mg.L-1. A oxida??o seguiu modelo cin?tico de pseudossegunda ordem, com valores de k2 de 0,0168 L.?g.min-1 para SMX (para ambas doses testadas), de 0,0133 e 0,0798 L.?g.min-1 para DCF, e de 0,0326 e 0,0289 L.?g.min-1 para E2, para doses de cloro de 1,5 e 3,0 mg.L-1, respectivamente. Por fim, verificou-se que o aumento do tempo de contato favoreceu a oxida??o dos f?rmacos, ainda que com a perspectiva de forma??o de subprodutos para SMX e E2.Pharmaceuticals and endocrine disrupting compounds are found in Brazilian natural waters, including some water sources for public supply, also due to the low coverage of sewage collection and treatment in Brazil. This study investigated the removal of three pharmaceutical compounds - sulfamethoxazole (SMX), diclofenac (DCF) and 17?-estradiol (E2) - from aqueous solutions by means of chlorine oxidation (sodium hypochlorite) by varying the dose of chlorine and contact time in batch tests. The chlorine solutions were examined by chromatography attached to the mass spectrometry in order to identify the oxidation by-products. For 10 min contact time, mean removal values of 61% were observed for DCF; 36% for E2; and 33% for SMX, when the chlorine dose was 1.5 mg L-1. Just for DCF there was a statistically significant difference (?=0.05) in the removal efficiency when increasing the chlorine dose to 3.0 mg.L-1. The oxidation followed the kinetic model of pseudo-second order, with k2 values of 0.0168 L.?g.min-1 for SMX (at both chlorine doses tested); 0.0133 and 0.0798 L.?g.min-1 to DCF; and 0.0326 and 0.0289 L.?g.min-1 to the E2 at chlorine doses of 1.5 and 3.0 mg L-1, respectively. Finally, it was verified that an increase of the contact time favored the oxidation of all pharmaceuticals tested, although with the perspective of by-products formation for SMX and E2

    High resolution mass spectrometry elucidation of captopril?s ozonation and chlorination by-products.

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    The article evaluated the degradation of the captopril in aqueous solution after ozonation and chlorination. The process was continuously monitored focusing on the identification, mass spectrometry and elucidation of its by-products by applying direct infusion and high performance liquid chromatography, electrospray ionization high resolution mass spectrometry, in the negative ion mode. The cytotoxicity of its by-products solutions were evaluated with 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. It was observed through that after 30 min of ozonation and chlorination, there was complete oxidation of captopril, i .e ., 100% removal efficiency. At these conditions, the rate of mineralization, by total organic carbon, was only 7.63% for ozonation and 6.40% for chlorination, evidencing the formation of degradation by-products. Ten captopril by-products were identified and their respective chemical structures elucidations are proposed. The treated samples and their by-products were nontoxic to HepG2 cells by MTT assay

    Use of aqueous two-phase PEG-salt systems for the removal of anionic surfactant from effluents.

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    Linear alkylbenzene sulfonates (LAS) are synthetic anionic surfactants that are extensively used in many industries. As a result, large volumes of effluents containing high levels of these compounds are discharged into water bodies, causing risks to aquatic flora and fauna. Then, there is a need for environmentally safe and economically viable technologies for the removal of LAS from aqueous matrices. The present work evaluates the use of aqueous two-phase systems (ATPS) composed of PEG and sulfate salts for this purpose, considering the effects of tie line length (TLL), molar mass of polymer, and type of cation-forming salt on the partitioning behavior of LAS. All the LAS partition coefficient (KLAS) values were greater than unity, and the LAS extraction efficiencies (%ELAS) were higher than 97%. The system consisting of PEG 1500 ? (NH4)2SO4 ? H2O provided the highest KLAS (1083.34) and %ELAS (99.9%), indicating that the method provided good extraction of LAS to the top phase. This system was applied using a real effluent sample in laboratory-scale experiments as well as in bench-scale batch trials. The results obtained at the laboratory scale showed %ELAS values greater than 98%, while the best KLAS value obtained in the batch experiments was 8.50 (?1.75) (%ELAS ? 78.17%). These values demonstrated the potential of ATPS for the removal of LAS from industrial effluents

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    Sloan Digital Sky Survey IV: mapping the Milky Way, nearby galaxies, and the distant universe

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    We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median ). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July

    Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe

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    We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratios in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially resolved spectroscopy for thousands of nearby galaxies (median z‚ąľ0.03z\sim 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between z‚ąľ0.6z\sim 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGNs and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5 m Sloan Foundation Telescope at the Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5 m du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in 2016 July
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