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Síntese esteresseletiva de bis-calcogenetos vinílicos catalisada por FeCL3
(Universidade Federal de Santa Maria, 2012-06-29)
Não foi possível inserir o abstract.
Síntese de Penta-2,4-dienonitrilas e 2-Cianometileno-but-3-enoatos de Etila via Olefinação de Horner-Wadsworth-Emmons e sua Aplicação na Obtenção de 4-Trifluormetil-piridin-2(1H)-iminas Substituídas e 2H-Piran-2-onas Análogas .
(Universidade Federal de Santa Maria, 2013-03-26)
This paper presents the Horner-Wadsworth-Emmons olefination applied
to preparing 22 new 5-alkoxy-3-trifluoromethyl-penta-2,4-dienenitriles (5), 5-
phenylthio-3-trifluoromethyl-penta-2,4-dienenitriles (6) and ethyl ...
Aproveitamento da casca de arroz para a produção de xilitol e sílica xerogel
(Universidade Federal de Santa Maria, 2009-12-01)
The generation of residual materials and its unavoidable disposal in the environment has been a reason of great concern, not only environmentally but also economically. The use of these renewable residual feedstocks, not ...
Determinação de impurezas elementares em fármacos e estudo de interferências em ICP-MS após decomposição em sistema de alta pressão e por combustão iniciada por micro-ondas
(Universidade Federal de Santa Maria, 2014-05-15)
In this work a wet microwave assisted digestion procedure using Multiwave® and UltraWave® systems, microwave induced combustion (MIC) and dry ashing decomposition method were evaluated for the digestion of levodope (LEVO), ...
Aspectos inorgânicos e físico-químicos na determinação espectrofotométrica do radical 1,1-difenil-2-picrilhidrazil.
(Universidade Federal de Santa Maria, 2020-11-06)
The DPPH method has been reported with misconceptions in a large number of studies,
precluding the direct comparison of results. Attention is drawn to a common mistake in the unit
used to express the IC50 value of ascorbic ...
Degradação de nonilfenol polietoxilado e de efluente têxtil por meio de eletrocoagulação e processos Fenton
(Universidade Federal de Santa Maria, 2004-07-29)
Nonylphenol polyethoxylates are nonionic surfactants widely
employed on textile industry. Submitted to inadequate effluent treatment processes, these compounds can be eventually biodegraded to metabolites with estrogenic ...
Combustão iniciada por microondas em sistema fechado para a decomposição de amostras biológicas
(Universidade Federal de Santa Maria, 2004-05-24)
A procedure for sample decomposition was proposed in this study based on sample combustion assisted by microwave radiation. Combustion is started by microwave radiation in the presence of oxygen under pressure using ammonium ...
Estudo sobre a versatilidade do caráter metálico do elemento telúrio contido em sistemas moleculares
(Universidade Federal de Santa Maria, 2019-07-26)
This work presents the synthesis and detailed structural analysis of a series of new complex salts of organotellurium halides with an emphasis on exploring the versatility of the metallic character of the tellurium atom, ...
Estudo multivariado de algumas propriedades termodinâmicas dos elementos terras raras
(Universidade Federal de Santa Maria, 2019-02-22)
Lanthanides (La-Lu), Yttrium and Scandium form the group of rare earth elements (REE) are classified as light (LREE) and heavy (HREE). These elements are gaining prominence in surveys due to their economic potential as ...
Sistemas emulsionados para análise de amostras com alto teor lipídico por espectrometria de absorção atômica
(Universidade Federal de Santa Maria, 2010-06-04)
The attention to the knowledge of nutritional and toxicological profiles of foodstuffs is increasing. Therefore, methods that allow for the determination of components desirable or necessary, as ...