Atom Surface Interaction
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. First-principles study of carbon chemisorption on γ-Fe(111) surface
In order to study the interaction between γ-Fe and carbon, the geometry structures, surface relaxations, adsorption energies and electronic structures for carbon chemisorption at four different adsorption sites on γ-Fe(111) surface at a monolayer coverage of 1 were studied using density functional theory. The electronic structures were compared with the ch
Brazilian Journal of Physics. Publicado em: 2010-12
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2. SELECTIVE DETERMINATION OF FLUORQUINOLONES FOR CELLULOSE SURFACE ROOMTEMPERATURE PHOSPHORIMETRY WHITH THORIUM NITRATE / DETERMINAÇÃO SELETIVA DE FLUOROQUINOLONAS POR FOSFORIMETRIA NA TEMPERATURA AMBIENTE SUPORTADA EM SUBSTRATO DE CELULOSE COM NITRATO DE TÓRIO
In this work, analytical methods based on solid surface room-temperature phosphorimetry were developed aiming the selective determination of fluorquinolones. More spectilly, thorium nitrate was evaluated as phosphorescence inducer aiming the sequential determination of norfloxacin (NOR) and levofloxacin (LEV), selective determination of NOR in presence of ci
Publicado em: 2007
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3. Análise teórica da superfície Si(111)-(7x7)
In this work, wecarry out theoretical study of the silicon surface reconstruction (7x7) grown in the [111] direction, denoted by Si(111)(7x7), using the Density Functional Theory formalism, within the Local Density Approximation (LDA) for the exchange correlation term. The interaction with the valence electrons and the core ion (nucleus more core electrons)
Publicado em: 2007
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4. Sintese , caracterizaÃÃo e eletroatividade de sams formadas com compostos catiÃnicos de tetraaminas de rutÃnio / Synthesis, characterization and eletroatividade of sams formed with composites catiÃnicos of tetraaminas of rutÃnio
Trans-[Ru(CNpy)(NH3)4(L)]2+ type complexes, where CNpy (4- Cyanopyridine), L= 1,4-dt (1,4-dithiane), pyS (4-mercaptopyridine), and Tio (thionicotinamide), were synthesized and characterized by HPLC, microanalysis, eletrochemistry and vibrational and eletronic spectroscopies. The eletrochemical and eletronic absorption results are indicative of a π back-
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 08/09/2006
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5. Dinâmica crítica de modelos de spin, autômatos celulares e polipeptídeos. / Critical dynamics of spin models, cellular automata and polypeptides.
In this work we investigated dynamic properties of statistical mechanical models at criticality. At first, using the concepts of global persistence and anomalous dimension of initial magnetization, we showed that the Baxter-Wu model does not belong to the same universality class as 4-state Potts model and Ising with multispin interaction in one direction. In
Publicado em: 2005
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6. Átomos próximos à superfície: interação de van der Waals. E diodo laser acoplado à transição atômica: realimentação incoerente
Interações dos átomos com superfícies modificam os graus de liberdade internos e externos desses átomos quando próximos a elas. A interação dominante de longo alcance (até a ordem do comprimento de onda das transições atômicas) é a interação de van derWaals, geralmente atrativa. Nesta tese é abordado o coeficiente C3, característico dessa in
Publicado em: 2005
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7. Um modelo para a superfície líquida no estudo da dinâmica do espalhamento de Xe e Ne pelo esqualano
In this work we present a theoretical model to investigate the scattering of Xe and Ne by a liquid squalane surface. The liquid surface is modeled as a grid of harmonic oscillators with frequencies adjusted to experimental vibration as frequencies of the liquid squalane and the atom-surface interaction potential is modeled by a Lennard-Jones function. The th
Química Nova. Publicado em: 2004-06
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8. Preparação, caracterização e avaliação de catalisadores heterogeneos a base de Pt na hidrogenação enantiosseletiva do piruvato de metila em presença de cinconidina
Platinum based catalysts were prepared by impregnation on different supports, namely C, Al303, TiO2 and La203. The commercial activated carbon was oxidized by different methods in order to modify its surface. The main surface groups identified were carboxylic acid, when HN03 is the oxidizing agent, and carbonyl, phenol and quinone, when the oxidation is made
Publicado em: 2000
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9. Computation of the sticking probability of a incident atom on metallic surface. / Cálculo da probabilidade de adesão de átomo incidente em superfície metálica.
A new procedure that calculates sticking coefficients for atomic beams incident upon metallic surfaces is discussed. A model Hamiltonian describing the normal incidence of an ad-atom and its interaction with the conduction electrons of the adsorbate is introduced. The Hamiltonian accounts for two couplings: (1) the overlap between the atomic orbital and the
Publicado em: 1986
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10. Friction traced to the single atom
Friction is caused by dissipative lateral forces that act between macroscopic objects. An improved understanding of friction is therefore expected from measurements of dissipative lateral forces acting between individual atoms. Here we establish atomic resolution of both conservative and dissipative forces by lateral force microscopy, presenting the resoluti
National Academy of Sciences.
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11. Probing the molecular mechanism of action of co-repressor in the E. coli methionine repressor-operator complex using surface plasmon resonance (SPR).
We have studied quantitatively the effect of the corepressor, S-adenosylmethionine (SAM), on the interaction between the E. coli methionine repressor, MetJ, and an idealised operator fragment, by recording measurements of surface plasmon resonance using a BIAcore instrument. We have recorded kinetic binding data in the presence of SAM, which carries a net po
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12. Crystallographic refinement of interleukin 1 beta at 2.0 A resolution.
The structure of human recombinant interleukin 1 beta (IL-1 beta) has been refined by a restrained least-squares method to a crystallographic R factor of 17.2% to 2.0 A resolution. One-hundred sixty-eight solvent molecules have been located, and isotropic temperature factors for each atom have been refined. The overall structure is composed of 12 beta-strand