Ion Molecule Reactions
Mostrando 1-12 de 26 artigos, teses e dissertações.
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1. A espectrometria de massas e as bio-moleculas : relação estrutura/reatividade de peptideos por reações ion/molecula e mobilidade de ions e busca de novos biomarcadores em clinica medica por imageamento quimio-seletivo de tecidos / Mass spectrometry and bio-molecules : structure-reactivity relation of peptides by ion/molecule reactions and ion mobility and search for new biomarkers in clinical medicini for chemo-selective imaging of tissues
The aim of this doctoral project was to study new applications of mass spectrometry (MS) to bio-molecules by using new techniques and recent approaches room pressure, with the goal of obtaining a more rapid and selective identification of an AA in a peptide sequence. Three-dimensional forms of the peptides and their fragment ions formed (a, b and y), were al
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/06/2010
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2. Solvolysis reactions of cation +SiCl3: Experiment and Theory / Reações de solvólise em fase gasosa do cátion +SiCl3: experimento e teoria
Polyhalogenated silicenium ions, X3Si+ (X = F, Cl), are common fragment ions in the mass spectra of polyhalogenated silanes obtained by electron ionization. These ions are powerful electrophiles and are believed to play a role in plasma enhanced corrosion processes and plasma enhanced chemical vapour deposition processes. In this dissertation, we present som
Publicado em: 2010
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3. Estudo da desativação do agente VX usando o MgO por cálculos ab initio
The organophosphates are used in industry, in the fields of dyes, varnishes, artificial leather, electrical insulation, waterproofing, plastics, oil additives and solvents, are also used in medicine to treat diseases such as glaucoma, in the household and in agriculture are applied as insecticides and pesticides. Besides these various civilian facilities, th
Publicado em: 2009
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4. New catalysts based on oxovanadium (IV) and cucurbit[6]uril. / Novos catalisadores à base de oxovanádio (IV) e Cucurbit[6]urila
Cucurbiturils are versatile molecules used in several branches of chemistry. These molecular cages form a family of homologues from the condensation of glycoluril and formaldehyde in acidic medium. Their applications range from catalysis, photochemistry, organic and inorganic synthesis, materials and supramolecular chemistry. Particularly cucurbit[6]uril, or
Publicado em: 2009
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5. Energética e mecanismos de processos iônicos em fase gasosa / Energetics and mechanisms of gas-phase ionic processes
The study of ionic reactivity in the gas-phase has been widely explored with mass spectrometry techniques. This thesis reports experimental and theoretical results in three different areas of gas-phase ion chemistry. The ionic processes were experimentally studied by Fourier transform mass spectrometry (FTMS or FT-ICR), a high resolution method that allows f
Publicado em: 2007
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6. Caracterização das reações do nitroprussiato de sodio com tiois e oxihemoglobina
Nitric oxide (NO) is a messenger molecule synthesized by mammals and plays a large number of biological roles, including the control of arterial pressure, neurotransmission and the inhibition of platelet aggregation. Sodium nitroprusside ([Na2[Fe (CN)5(NO)], SNP) is an NO donor metal complex used clinically for over 70 years in the control of hypertension cr
Publicado em: 2003
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7. Gas-phase ion chemistry of silyl cations obtained from hexamethyldisilazane
The gas-phase ion-molecule reactions of the Me3SiN(H)SiMe2+ ion, obtained by electron ionization from Me3SiN(H)SiMe3, have been studied in a Fourier transform ion cyclotron resonance spectrometer in order to understand the mechanistic details of an important chemical system presently used in film formation. This silyl cation has been observed to undergo addi
Química Nova. Publicado em: 2002-09
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8. Aplicações de tecnicas modernas de espectometria de massas em quimica analitica e em estudos de mecanismos de reações na fase gasosa
In this work techniques of mass spectrometry were used to quantify semivolatile compounds in pharmaceutical preparations, for fingerprint of samples of national and imported beers and in the reactions monitoring in aqueous media and in gaseous phase. These studies had been divided in six parts. The biocatalisys reactions monitoring were carried in order to v
Publicado em: 2002
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9. Hidrogenofosfato de titânio lamelar: síntese, troca iônica e intercalação
The development associated with the research field involving crystalline inorganic lamellar titanium hydrogenphosphate, Ti(HPO4).H2O, synthesized as alpha or gamma forms, is directly linked to the huge number of reactions, that occur inside the free interlamellar space. Two distinguishable well-characterized features such as ion-exchange and intercalation re
Química Nova. Publicado em: 2001-12
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10. Estudo da reatividade de ions e moleculas por colisões dissociativas e reações ion-molecula em fase gasosa via espectrometria de massas pentaquadeupolar
To study the gas phase chemistry of ions and molecules, some enaminones, two heterocumulene C2NO2 isomers and several isomers of pyridinium, pyrimidinium, furanyl and thiophenyl ions were chosen as systems of interest. Enaminones, were chosen because they have been extensively studied in solution by our research group. Firstly, the eletrophilic addition of m
Publicado em: 1998
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11. Estudo de reações ion/molecula na fase gasosa por espectrometria de massa de estagios multiplos (MS2 e MS3) em um espectrometro pentaquadrupolar
This work presents the results of four distinct projects which have been focused on combined studies of ion/molecule reactions, collision-induced dissociation of ions and ab initio calculations. In the first project it was verified the occurrence in the gas phase of novel ionic 1,3-dipolar cycloaddition reactions between carbonyl compounds and the simplest c
Publicado em: 1996
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12. Determinação do volume de ativação de reações de hidrolise acida de complexos de alfa-diiminas não simetricas com ferro (II)
The dissociation of Iron (II) complexes with diimines can be visualized presently by two different mechanisms. Basolo´s mechanism considers the nucleophilic attack on the metallic central ion. Gillard´s suggestion supposes the attack on the molecule of the ligand. To contribute for a better understanding of this kind of reaction we did a comparative study
Publicado em: 1990