Sulfite Determination
Mostrando 1-8 de 8 artigos, teses e dissertações.
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1. A Fast, Low-Cost, and Environmental Friendly Micro-Flow-Batch Analyzer for Photometric Determination of Sulfites in Beverages
An automated microsystem for sulfite determination in beverages was developed. It presents higher sampling throughput, lower chemical consumption and less waste generation than previous flow methods, while using the same p-rosaniline-formaldehyde-sulfite reaction. The sampling rate, limit of detection (LOD), and relative standard deviation (RSD) were estimat
J. Braz. Chem. Soc.. Publicado em: 08/04/2019
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2. Sulfites in beer: reviewing regulation, analysis and role
ABSTRACT Beer is an extremely complex mixture of more than 3,000 different compounds in an aqueous environment. Thus, it is perhaps not surprising that the maintenance of beer quality throughout its lifetime has been a considerable challenge for brewers. Whilst it is inevitable that chemical changes will occur in beer with the passage of time, it is the form
Sci. agric. (Piracicaba, Braz.). Publicado em: 2016-04
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3. Sulfite induced autoxidation of Ni(II), Co(II) and Cu(II) / tetra, penta and hexaglycine complexes. Chemiluminescent determination of S(IV) and acetaldehyde / Autoxidação dos complexos de tetra, penta e hexaglicina de Ni(II), Co(II) e Cu(II) induzida por S(IV). Determinação de S(IV) e aldeídos por quimiluminescência
The autoxidation of Ni(lI) and Co(lI) complexes with tetra, penta and hexaglycine, in borate medium, is accelerated by sulfur (IV) species (H2S03, HS03- and SO32-). The formation of Ni(llI) and Co(lIl) complexes was followed spectrophotometrically at 325 and 265 nm, respectively. The autoxidation rate of Ni(II)/Gn complex increases with S(IV) concentration a
Publicado em: 2007
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4. Estudo da transmissão da imunidade passiva e da mortalidade em cordeiros mestiços de Santa Inês, na região norte de Minas Gerais
The transferring of passive immunity and the causes of mortality lambs breed and crossbreed Santa Inês were studied this work developed in north of Minas Gerais. The transferring of passive immunity was determined by laboratory and field tests. The main causes of neonatal mortality up to 90 days of age were identified by necropsies. Sixty-nine Santa Inês e
Publicado em: 2006
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5. Avaliação e síntese de corantes fenotiazínicos para determinação espectrofotométrica de sulfeto e sulfito empregando sistemas de análise em fluxo.
In this work seven aromatic amines O e N-substituted were evaluated at optimized reaction conditions for symmetrics phenothiazinic dyes. DMPD, DEPD, PPD, PAP e PAA were the start reagent, where the yield for phenothiazinic dyes varying from 10% to 43% for different oxidizing (Fe3+ or ClO-), acids (H2SO4 or HBF4) and precipitant agent (ClO4 - or BF4 -). The l
Publicado em: 2004
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6. Spectrophotometric and chemiluminescence studies of S(IV) induced autoxidation of Ni(II) or Cu(II)/tetraglycine complexes. Analytical applications. / Estudos espectrofotométricos e por quimiluminescência da autoxidação de complexos de Ni(II) ou Cu(II)/tetraglicina induzida por S(IV). Aplicações analíticas
The current work shows studies concerning the sulfite induced Ni(II)/tetraglycine (NiIIG4) and Cu(II)/tetraglycine (CuIIG4) autoxidation reaction in aqueous medium. Spectrophotometric studies focused on the formation of the correspondent metallic ion in the 3+ oxidation state. It was found that S(IV) accelerates NiIIG4 autoxidation at pH = 9.2 (borate buffer
Publicado em: 2004
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7. Determination of Escherichia coli Contamination with Chromocult Coliform Agar Showed a High Level of Discrimination Efficiency for Differing Fecal Pollution Levels in Tropical Waters of Kampala, Uganda
Escherichia coli, total coliforms, fecal coliforms, and sulfite-reducing anaerobic spore formers from different polluted sites in a tropical environment were determined in order to test for their indication ability for fecal contamination. Quantification of E. coli contamination with Chromocult coliform agar proved to be efficient and feasible for determinin
American Society for Microbiology.
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8. Redox Potentials of Certain Vitamins K: Implications for a Role in Sulfite Reduction by Obligately Anaerobic Bacteria
Redox potentials of a menaquinone (MK-6), isolated in earlier researches from two species of the obligately anaerobic genus, Desulfovibrio, as well as two other vitamins K2—menaquinones (MK-5) and (MK-9)— have been determined polarographically. The measurements have been validated by determination of redox potentials of 1,4-naphthoquinone and vitamin K1