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Estudo da influência de modificadores químicos para a determinação de chumbo por GF AAS na presença de sulfatos
(Universidade Federal de Santa Maria, 2005-03-03)
Lead determination by graphite furnace atomic absorption spectrometry may be affected by some interferences. Several authors have reported that lead determination may be affected in the presence of some salts (carbonates ...
Determinação de cádmio e manganês com pré-concentração por FI-FAAS e aplicação em aditivo alimentar à base de fosfatos
(Universidade Federal de Santa Maria, 2005-09-02)
Cadmium is a toxic element even at low concentration and is no essential for human metabolism, while Mn is essential and no toxic at low concentration. For that reason, it is important to have sensitive and accurate methods ...
Síntese de 4-(fur-2-il)- e 4-(tien-2-il)-pirimidinas a partir de β-Alcoxivinil trifluormetil cetonas
(Universidade Federal de Santa Maria, 2005-08-01)
The cyclocondensation of the 1,1,1-trifluoro-4-methoxy-4-(2-heteroaryl)-3-buten-2-ones (heteroaryl = furyl and thienyl) with urea and amidines (acetamidine, benzamidine, guanidine, 1H-pyrazole-1-carboxamidine and ...
Síntese de 1h-1,2,3-triazol-4-il-1,3,4-oxadiazóis a partir de 4-alcóxi-1,1,1-tricloro-3-alquen-2-onas
(Universidade Federal de Santa Maria, 2014-09-12)
This work describes the synthesis and the characterization of series of substituted trichloroacetyl 1H-1,2,3-triazoles (10 12), 1H-1,2,3-triazol-4-yl-carbohydrazides (14 16) and 1H-1,2,3-triazol-4-yl-1,3,4-oxadiazoles ...
Obtenção quimiosseletiva de trialometil-β-dicetonas via reações de acilação de acetais
(Universidade Federal de Santa Maria, 2009-02-27)
This work presents an Acylation Method of Acetals applied to the quimioseletive obtention of trifluormethyl-β-diketones, incluing acetals derived from not symmetrical ketones and functionalized substituents. Five known ...
Obtenção regiosseletiva de 5-alquil(aril/heteroaril)-3- (carboxil/trifluormetil)-1h-1-fenilpirazóis
(Universidade Federal de Santa Maria, 2011-05-19)
This paper presents a new synthetic route for obtain regioselective 5-alkyl(aryl/heteroaryl)-3-trifluoromethyl-1H-1-phenylpyrazoles (3a-e) (50-85% yields) and 5-alkyl(aryl/heteroaryl)-3-carboxialkyl-1H-1-phenylpyrazoles ...
Desenvolvimento de sistema para piroidrólise para o preparo de papelão hidráulico visando a determinação de halogênios
(Universidade Federal de Santa Maria, 2014-08-14)
A pyrohydrolysis system was developed for sample preparation for halogen
determination in hydraulic cardboard. These materials are used for sealings,
mainly engines and nuclear reactors. Because of the contact of the ...
5-trialometil-4,5-diidro-1h-1-(carbonilpiridil)pirazóis: síntese e atividade biológica frente ao Mycobacterium tuberculosis
(Universidade Federal de Santa Maria, 2008-08-06)
This work describes the synthesis of series of 5-hydroxy-3-[alkyl(aryl/heteroaryl)]-5-trifluoro[chloro]methyl-4,5-dihydro-1H-1(carbonylpyridyl)pyrazoles, obtained from the
reactions of 1,1,1-trihalo-4-[alkyl(aryl/hetero ...
Validação de procedimento analítico empregando SPE e GC-ECD para determinação de pesticidas organoclorados em água e avaliação da permeabilidade destes nos dialisadores utilizados em hemodiálise
(Universidade Federal de Santa Maria, 2004-08-27)
The dialysis of the blood, within which the most applied modality is the haemodialysis, is a method thoroughly used for the treatment of the renal inadequacy. With this treatment, toxic substances accumulated in the patient´s ...
Decomposição de coque, resíduo de vácuo e petróleo extrapesado por piroidrólise para a determinação de cloro
(Universidade Federal de Santa Maria, 2007-10-26)
In this work, a method for chlorine determination in petroleum coke, vacuum and atmospheric residues and heavy petroleum was developed. The pyrohydrolysis sample decomposition method was used, which consists of sample ...