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Síntese regiosseletiva de 2-metiltiopirimidin-4(3h)-onas N3-substituídas, uracilas derivadas e bromacil análogos
(Universidade Federal de Santa Maria, 2014-01-31)
A series of twenty-seven 3,6-disubstituted 2-methylthiopyrimidin-4(3H)-ones that have as substituents at 6 position of the pyrimidine ring the groups Me, Ph, 4-Me-C6H4, 4-OMe-C6H4, 4-F-C6H4, 4-Br-C6H4 and at 3 position the ...
Síntese de Seleno-Isoxazóis e Seleno-Indóis via Reações de Ciclização Intramolecular mediadas por Cloreto Férrico
(Universidade Federal de Santa Maria, 2013-03-05)
This work reports the synthesis of a series of 4-organoselenyl-isoxazoles (19 examples), prepared via FeCl3/diorganyl diselenides-promoted intramolecular cyclization of alkynone O-metyloximas. In general, the selenyl-isoxazoles ...
Síntese de Calcogenofenos e Isoquinolinas via Reações de Ciclização Intramolecular
(Universidade Federal de Santa Maria, 2013-11-26)
In the first part of this work, a series of selenophenes and tellurophenes were prepared starting from of (Z)-chalcogenoenynes, by employing FeCl3 diorganyl dichalcogenide-mediated intramolecular cyclization. In general, ...
Desenvolvimento de método para a determinação simultânea de resíduos de agrotóxicos e medicamentos veterinários em solo por UHPLC-MS/MS
(Universidade Federal de Santa Maria, 2013-08-30)
Typically, soil is the final destination of pesticides applied in agriculture and of veterinary drugs employed in animal production. The global concern about the possible consequences of the increased use of these compounds ...
Síntese, propriedades e investigação estrutural de 1,3-diariltriazenos e complexos com Ni(II), Pd(II), Pt(II) e Hg(II)
(Universidade Federal de Santa Maria, 2006-08-04)
Although transition metal complexes with nitrogen coordination spheres involving monocatenated 1,3-diarylsubstituted triazenido ligands (ArNNNAr)−, have been investigated in the last decades, the structure of such compounds ...
Biorremediação de herbicidas em água do cultivo de arroz irrigado visando minimizar o impacto ambiental
(Universidade Federal de Santa Maria, 2008-12-22)
Irrigated rice production depends on the pesticides application, among other factors. Herbicides could be highlighted as the most used ones, which may be transported into natural water sources, generating pollution and ...
Determinação de cádmio, cobre e chumbo por F AAS e GF AAS em plantas medicinais empregando amostragem direta de sólidos
(Universidade Federal de Santa Maria, 2005-07-29)
The main objective of this study was to use alternative systems for the analysis of solids by graphite furnace atomic absorption spectrometry (DSS-GF AAS) and with flame (SS-F AAS) for cadmium, copper and lead in determination ...
Determinação de contaminantes orgânicos em matrizes complexas utilizando método QuEChERS e cromatografia líquida acoplada à espectrometria de massas de alta resolução
(Universidade Federal de Santa Maria, 2016-03-04)
The presence of organic contaminants in the environment and in food have become a major concern due to the harmful effects to living organisms. Such contaminants may be pesticides used in agriculture for the control of ...
Determinação de tiocompostos por voltametria e coulometria em matrizes salinas
(Universidade Federal de Santa Maria, 2006-08-11)
The Laboratory of Support to Hemodialysis Clinics (LACHEM) has been investigating for many years the behaviour of many species in saline matrices as hemodialysis salts. In this work, the determination of the five thiocompounds ...
Estudo fitoquímico da raiz da espécie Melochia chamaedrys St. Hil
(Universidade Federal de Santa Maria, 2005-11-04)
Melochia chamaedrys St.Hil. is a plant that is locally known as douradinha , it is found in South America, more exactly in the south of Brazil, Argentina, and Uruguay. In the state of Rio Grande do Sul , the species M. ...