Atomic Vapor
Mostrando 1-12 de 88 artigos, teses e dissertações.
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1. Mercury Concentration in Liver Tissues of South American Fur Seals (Arctocephalus australis) from Southwestern Atlantic Ocean
Mercury (Hg) contamination of oceans is rapidly increasing, however Hg bioaccumulation in pinnipeds has been understudied. Here, we report for the first time Hg concentration in liver tissues of South American fur seals (Arctocephalus australis) in South and Southeast Brazil. Hg concentration was determined in twenty-five fur seals’ specimens found strande
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. DETERMINAÇÃO DE MERCÚRIO EM FÍGADO DE TETRÁPODES MARINHOS POR ESPECTROMETRIA DE FLUORESCÊNCIA ATÔMICA ACOPLADA A GERAÇÃO DE VAPOR FRIO (CV-AFS) E ESPECTROMETRIA DE MASSA COM FONTE DE PLASMA INDUTIVAMENTE ACOPLADO (ICP-MS): UMA COMPARAÇÃO SISTEMÁTICA ENTRE AS DUAS TÉCNICAS
This study compares the techniques cold vapour atomic fluorescence spectrometry (CV-AFS) and inductively coupled plasma mass spectrometry (ICP-MS) for the determination of Hg in biological samples (hepatic tissue from marine tetrapods). Acid digestions were performed for the samples and aliquots of them were analysed by ICP-MS and CV-AFS. To minimize the Hg
Quím. Nova. Publicado em: 2021-01
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3. Determining Mercury in Sediment Samples by Extraction Using a Novel-Chelating Reagent Dithiothreitol (DTT) Followed by Cold Vapor Atomic Fluorescence Spectrometry (CV-AFS)
A new analytical protocol has been developed for the determination of mercury in surface sediments using dithiothreitol (DTT) as a new chelating reagent for the extraction. This protocol requires a small sample mass (250 mg), 4.0 mL of a 0.1 M (pH = 9.0) aqueous DTT solution, and sonication for 30 min, followed by cold vapor atomic fluorescence spectrometry
J. Braz. Chem. Soc.. Publicado em: 2020-12
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4. On the Effect of Aluminum on the Microstructure and Mechanical Properties of CrN Coatings deposited by HiPIMS
Hard coatings are a suitable solution for increasing the lifetime of tools and components employed in different industrial applications. Coatings of transition metal nitrides have great use for tribological applications due to due to their unique mechanical properties. Although widely employed, current deposition methods such as cathodic arc evaporation prod
Mat. Res.. Publicado em: 12/04/2018
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5. Determination of Hg in Biological Samples and Ethanol Fuel by Photochemical Vapor Generation after Pre-Concentration in a Gold Trap
In this work, the photochemical vapor generation (PVG) coupled with atomic absorption spectrometry and a pre-concentration step with an Au column was used for the determination of Hg in biological samples and ethanol fuel. PVG with pre-concentration showed an up to 250-fold higher sensitivity compared to the approach without pre-concentration. The accuracy o
J. Braz. Chem. Soc.. Publicado em: 2017-09
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6. The correlation between tribological properties of nanostructure TiN coatings and deposition process parameters in PACVD system
ABSTRACT Titanium base coatings are being used extensively for improving wear characteristics at the surface of different parts. Titanium nitride was deposited by Plasma Assisted Chemical Vapor Deposition (PACVD) techniques with purpose improve interface with substrate, as this can increase wearing of the entire part in spite of desirable wear behavior of Ti
Matéria (Rio J.). Publicado em: 22/06/2017
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7. Study of the Adsorption of Arsenic (III and V) by Magnetite Nanoparticles Synthetized via AACVD
Globally, water pollution is mainly caused by the presence of heavy metals and metalloids such as arsenic. The majority of the techniques employed in the removal are of low efficiency and high cost. Therefore, in this work it is presented the adsorption processes of arsenic (As III and V) ions employing magnetite nanoparticles (MNPs) synthesized by the aeros
Mat. Res.. Publicado em: 08/12/2016
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8. Evaluation of Major and Trace Elements in Medicinal Plants
This study presents the elemental concentration results obtained from 59 medicinal plants used in Brazil, determined by instrumental neutron activation analysis (INAA), inductively coupled plasma-optical emission spectrometry (ICP OES) and cold vapor atomic absorption spectrometry (CV AAS). The selected plant species were chosen from the Brazilian National A
J. Braz. Chem. Soc.. Publicado em: 2016-12
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9. Feasibility of Using AAS for the Characterization of a Tuna Fish Candidate Reference Material for Total Hg and Methyl-Hg Measurement
This work describes the evaluation of several parameters for preparing a tuna fish candidate reference material (RM) in order to measure its total Hg and methyl-Hg mass fractions by cold vapor atomic absorption spectrometry (CV-AAS) and solid sampling graphite furnace atomic absorption spectrometry (SS-GF AAS). Best results were acquired after extraction wit
J. Braz. Chem. Soc.. Publicado em: 2016-04
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10. Supramolecular Architecture and Electrical Properties of a Perylene Derivative in Physical Vapor Deposited Films
The supramolecular structure of organic thin films is a key factor in their optical and electrical properties and, consequently, in the technological applications involving organic electronic. Here, thin films of a perylene derivative, the bis butylimido perylene (BuPTCD), were produced by vacuum thermal evaporation (PVD, physical vapor deposition). The main
Mat. Res.. Publicado em: 17/11/2015
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11. Total Mercury Determination in Petroleum Green Coke and Oily Sludge Samples by Cold Vapor Atomic Fluorescence Spectrometry
A fast, simple and reliable method for Hg determination in green coke and oily sludge samples by atomic fluorescence spectrometry is described. Microwave digestion and extraction procedures were evaluated for highly complex samples of coke and oily sludge. The concentrations of SnCl2 and HCl to promote Hg vapor, were optimized, as well as the concentration o
J. Braz. Chem. Soc.. Publicado em: 2015-10
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12. Syntesis of Carbon Nanostructures Near Room Temperature Using Microwave PECVD
Carbon nanostructures (nanotubes, nanofibers and nanosponges) were synthesized onto Si (001) substrates using a microwave assisted plasma enhanced chemical vapor deposition (PECVD) from C2H2-Ar mixtures at low substrate temperatures (120 °C). Catalytic films (Ni and Cu) 3 nm thick were used. Different structures were formed, depending on the C2H2 partial pr
Mat. Res.. Publicado em: 2015-08