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Aplicação da amostragem direta-GF AAS para a determinação de elementos traço em metérias-primas para a produção de poliuretanos
(Universidade Federal de Santa Maria, 2010-02-04)
Polymeric diphenylmethane diisocyanate (PMDI) and diphenylthane dianiline (MDA) are importante raw materials in the manufacture of polyurethanes. These products have wide application in various fields such as medicine, ...
Aplicação de métodos voltamétricos de análise na especiação de cromo, selênio e antimônio em matrizes salinas
(Universidade Federal de Santa Maria, 2010-02-04)
This work aimed to explore the speciation analysis of chromium, selenium and antimony, elements of clinical and geochemical relevance, in the saline samples seawater, hydrothermal fluid and hemodialysis fluid. These samples, ...
Reações entre ácidos β-cianocarboxílicos e nitrogênios nucleofílicos: uma eficiente estratégia para a síntese de succinimidas, pirrolidinonas e tetrazóis
(Universidade Federal de Santa Maria, 2011-02-25)
This work presents the synthesis of 41 succinimides, 24 pyrrolidinones and 8 tetrazoles, all presenting unprecedented chemical structure, except for the
succinimide 3-ethoxy-1-methylpyrrolidine-2,5-dione. These compounds ...
Estudo fitoquímico e biológico das espécies Schinus lentiscifolius, Schinus terebenhtifolius, Schinus molle e Schinus polygamus (Anacardiaceae) do RS
(Universidade Federal de Santa Maria, 2012-01-16)
The phytochemical and biological study of the species S. lentiscifolius,
S. terebinthifolius, S. molle and S. polygamus known as ―aroeiras‖ (Anacardeaceae)
distributed in Rio Grande do Sul, was carried out to establish the ...
Métodos individual e multirresidual para determinação de pesticidas em grãos e derivados por GC-PFPD, GC-ITD-MS e LC-MS/MS
(Universidade Federal de Santa Maria, 2011-08-29)
Due to the complexity of grains like soybean, corn and rice, and the very low
pesticide concentration expected for these samples, it is really necessary to develop
efficient and reliable analytical methods to identify and ...
Síntese de heteroarilazóis trialometilsubstituídos a partir de 2-acetilfurano e 2-acetiltiofeno
(Universidade Federal de Santa Maria, 2004-04-07)
The synthesis of 1,1,1-trihalo-4-methoxy-4-[2-thienyl]-3-buten-2-ones, 1,1,1-trihalo-4-methoxy-4-[2-furyl]-3-buten-2-ones and the respective trihalomethyl 1,3-butanone derivatives by trihaloacylation of dimethoxy acetals
derived ...
Determinação das constantes de estabilidade dos complexos formados entre os aminoácidos cisteína, N-acetilcisteína e lisina com chumbo em solução aquosa
(Universidade Federal de Santa Maria, 2011-01-18)
In this study we investigated the interaction between lead and the amino acid cysteine, lysine and N-acetylcysteine by testing long-term contact with ion exchanger resins and also the determination of stability constants. ...
Determinação de resíduos de compostos orgânicos em água por microextração líquido-líquido dispersiva (DLLME) E GC-(TQ)MS/MS
(Universidade Federal de Santa Maria, 2010-11-29)
The use of chemicals, which generates a lot off benefits, is responsible for the contamination of soil, water and foods. The concern about contamination of surface
and ground water systems by pesticides has grown in ...
Síntese e avaliação de arranjos supramoleculares de triazenos monocatenados e complexos com os cátions Co3+, Cu2+, Ag+ e Au+
(Universidade Federal de Santa Maria, 2010-08-31)
Triazenes ligands substituted by terminal aryl groups in the diazoamine chain [ N=N N(H) ] containing NO2 group substituted in different position and ortho C(O)NH2 on aryl ring was evaluated on the occurrence of intermolecular ...
Estudo do comportamento químico de heterociclos trifluormetil substituídos em reações com DAST
(Universidade Federal de Santa Maria, 2011-03-01)
This work describes the study of the chemical behavior of trifluoromethyl substituted heterocycles as 1H-pyrazoles, 2-pyrazolines, 2H-cromenones and isoxazolines in reactions with DAST, with the aim of evaluating possible ...