Buscar
Itens para a visualização no momento 61-70 of 467
Nanotubos de carbono interagindo com vitaminaS B3 e C: um estudo de primeiros princípios
(Universidade Federal de Santa Maria, 2008-03-18)
This work presents a theoretical study about the interaction between pristine or functionalized B3 and C vitamins with semiconducting carbon nanotubes (8,0) through first principles simulations. We evaluate the structural ...
Vidro de spin e antiferromagnetismo com interacão de pareamento BCS local
(Universidade Federal de Santa Maria, 2005-07-12)
In this work the competition among spin glass(SG), antiferromagnetism (AF) and BCS pairs formation (PAIR) in real space is investigated. The model consists of an Ising spin glass term and a local BCS term that favors double ...
Estudo de primeiros princípios da interacão de monóxido de carbono com nanotubos de carbono semicondutores
(Universidade Federal de Santa Maria, 2004-10-08)
In this work we study the interaction of carbon monoxide with semiconducting (8,0)carbon nanotube through a first principles theoretical approach. Using density functional theory based methods, we show that radial ...
Estudo de propriedades estruturais, eletrônicas e magnéticas de clusters de Rh13, Pd13 E Pt13
(Universidade Federal de Santa Maria, 2009-08-11)
This work shows a theoretical study of Rh13, Pd13, and Pt13 clusters, using first principles methods. We sought to understand aspects of stability and magnetic moment for these systems. The employed methodology was tested ...
Pirólise lenta de serragem de eucalipto para obtenção de bioóleo e carvão
(Universidade Federal de Santa Maria, 2004-07-26)
This dissertation presents the slow pyrolysis of eucalyptus sawdust as an alternative, thermal process of treatment of forestry residues for the obtainment of gaseous, liquid and solid products. With the aid of a pyrolysis ...
Avaliação de procedimentos de digestão para determinação voltamétrica de traços metálicos em aminoácidos usados em nutrição parenteral aplicação na determinação de cádmio e chumbo
(Universidade Federal de Santa Maria, 2004-09-17)
In this work, the interaction of all the amino acids that compose the parenteral nutrition solutions, was investigated with the cadmium and lead metals, with the objective of determining the levels of contamination and if ...
Especiação de mercúrio em cogumelos por LC-CVG-ICP-MS: avaliação de procedimentos de extração
(Universidade Federal de Santa Maria, 2009-07-31)
In this work, different sample preparation procedures for determining inorganic (in Hg2+ form) and organic mercury (in methylmercury form CH3Hg+) in edible mushrooms were evaluated. Conventional, microwave (MW) and ...
Determinação de cloridrato de propranolol em medicamentos por espectroscopia no infravermelho com calibração multivariada (PLS)
(Universidade Federal de Santa Maria, 2005-07-21)
In this work calibration multivariate models were developed with the use of the technique of partial least scores (PLS) for the dosage of tablets of propranolol hydrochloride using infrared spectroscopy. Samples were ground ...
Determinação de cádmio, cobre e chumbo em catalisadores por espectrometria de absorção atômica com forno de grafite e amostragem direta de sólidos
(Universidade Federal de Santa Maria, 2006-07-26)
Trace impurities of Cd, Cu and Pb were determined in alumina-based catalysts using direct solid sampling graphite furnace atomic absorption spectrometry (DSS-GF AAS). The analyzed catalysts are widely used in petrochemical ...
Síntese e cristaloquímica de complexos de mercúrio(ii) com o ligante 1-(3-trifluorometilfenil)-3-(3-nitrofenil)triazeno
(Universidade Federal de Santa Maria, 2005-08-01)
This work shows the crystaline/molecular structure of two mercury(II) complexes with a same monocateneted triazene ligand previolsly deprotonated. The reaction between mercury(II) acetate, 1-(3-nitrophenyl)-3-(3-trifluor ...