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Disertaciones |
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1
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VAGNER OLIVEIRA SANTOS
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PRODUCTION AND CHARACTERIZATION OF FINE MOVIES SnO2: F PER SPRAY PYROLYSIS
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Líder : DENIS GILBERT FRANCIS DAVID
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MIEMBROS DE LA BANCA :
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ANTONIO FERREIRA DA SILVA
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DENIS GILBERT FRANCIS DAVID
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GIOVANNA MACHADO
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Data: 19-feb-2019
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Resumen Espectáculo
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In recent years, interest in the production of transparent oxide films has grown because of the many technological applications of theses oxides in the industrial production of electronic devices that use visualization display, gas sensors and electrodes in solar cells. Among the transparent oxides, indium oxide is the most widely employed because of its excellent optical and electrical properties. However, the large-scale use of indium oxide has been increasingly limited by the high cost of Indium ores. Due to its improved optical and electrical properties, low cost, high thermal and mechanical stability, fluorine doped oxides (SnO2: F) have proved to be one of the most promising materials as an alternative to indium oxides. Therefore, in the present work it is reported the construction of an experimental workbench that allows the production of SnO2: F films with thickness controlled by the spray pyrolysis deposition method. The control of the film thickness was achieved by the simple adjustment of the spray nozzle height, showing a strong linear correlation (R = 0.999) between this adjustment and the film thickness. The SnO2 films produced in the experimental setup had thicknesses in the range of 520 to 1240 nm and their morphological, textural, structural, optical and electrical properties. were characterized. In the morphological and textural characterizations, from the images obtained with MEV and AFM, the films were homogeneous and with granular appearance, presenting values of average roughness (Ra) and average grain size in the range of 92.1 to 121.6
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2
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Antonio Carlos Gonçalves da Silva
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A Study on the Principle of Weiss in General Relativity
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Líder : MARIO CEZAR FERREIRA GOMES BERTIN
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MIEMBROS DE LA BANCA :
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CARLOS ENRIQUE VALCARCEL FLORES
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HUMBERTO DE ALMEIDA BORGES
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JULIO MARNY HOFF DA SILVA
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MARIO CEZAR FERREIRA GOMES BERTIN
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Data: 29-mar-2019
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Resumen Espectáculo
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This dissertation addresses the Theory of General Relativity as field theory, from the point of view of the Weiss Variational Principle. It is presented and used highlighting the fact that it defines the field equations and the boundary terms of the variational problem. From it, we will examine information encoded in terms of boundary, such as the quantities conserved by symmetries. Our objective is to analyze the General Relativity in the formalism in terms of the metric and of Palatini in the light of this variational principle, applying the same to the case of the Topologically Massive Gravity in three dimensions.
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3
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ALINE GRAMACHO FAVERO
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Hadronic spectroscopy via QCD no gauge of Coulomb
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Líder : LUCIANO MELO ABREU
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MIEMBROS DE LA BANCA :
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LUCIANO MELO ABREU
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MARIO CEZAR FERREIRA GOMES BERTIN
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FERNANDO SILVEIRA NAVARRA
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Data: 16-may-2019
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Resumen Espectáculo
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The objective of this work is the analysis of axial resonances and exotic states in sectors of the foreigner, botomônio and charmônio. We use a method that the exact QCD Hamiltonian in the Coulomb gauge by an effective Hamiltonian with a confining potential and a transverse hyperfine interaction. A transformation of similarity (BCS) is applied, diagonalizing the Hamiltonian in a new base of quasiparticles. We apply, then, variational calculations to obtain the equation of the quasiparticle mass gap, and we used the RPA and the TDA to represent the excited.
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4
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ADSON SOARES DE SOUZA
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Analytical Advances about the apex Field Enhancement Factor of a Hemisphere on a Post Model
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Líder : THIAGO ALBUQUERQUE DE ASSIS
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MIEMBROS DE LA BANCA :
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RICHARD GORDON FORBES
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ROBERTO RIVELINO DE MELO MORENO
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THIAGO ALBUQUERQUE DE ASSIS
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Data: 05-jul-2019
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Resumen Espectáculo
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I’d like to thank a couple people, which, in a way or another, helped me arrive where I am right now. Jehovah, the God of the Bible, for everything He has done for me. Professor Thierry Jacques Lemaire, whose lectures (besides really awesome) were the primary reason why I decided to choose the physics course when I was an undergraduate student, still in engineering. Professors Mario Cezar Ferreira Gomes Bertin, Newton Barros de Oliveira,
Gildemar Carneiro dos Santos, Thiago Albuquerque de Assis, and Diego Cata- lano Ferraioli, for the great lectures when I was an undergraduate student.
These were really enjoyable classes. Professor Diego Catalano Ferraioli for encouraging me and giving me the initial kick, in a matter of speaking, for me to start the master program in the first place. Professors Julien Chopin and Denis Gilbert Francis David for the awesome lectures while I was in the graduate program, full of really interesting math, calculations, and interesting topics outside the main books. My supervisor, Thiago Albuquerque de Assis, for exposing me to scientific literature and some open problems, for showing me how things work in the scientific world, for showing me some aspects about what it takes to be a good scientist, for the (almost always) weekly meetings with insightful talks, and especially for always being motivating.
My dad, for his support and encouragement to write and finish this disser- tation and the research.
Also, I’d like to thank CNPq for finantial support.
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5
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Eduardo Cerqueira Ribeiro
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OPTIMIZATION OF ATOMIC BASIS OF DOUBLE-ZETA TYPE FOR THE
BORON ATOM USING ALGORITHM HF Gauss - GSA
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Líder : MICAEL DIAS DE ANDRADE
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MIEMBROS DE LA BANCA :
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FREDERICO VASCONCELOS PRUDENTE
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KLEBER CARLOS MUNDIM
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MICAEL DIAS DE ANDRADE
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Data: 05-jul-2019
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Resumen Espectáculo
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In this work, we present a new Double Zeta (DZ) atomic basis set for the boron atom. This atomic basis set was obtained using the HFGauss-GSA algorithm, which is a direct minimization procedure of the Hartree-Fock functional. This algorithm is based on the Generalized Simulated Annealing method. This algorithm does not solve necessary condition equations nor does it use orbital occupation rules, guaranteeing, in principle, obtaining the absolute minimum of the electronic energy functional. The HFGauss-GSA algorithm considers as arguments of this functional the coecients and exponents of the Gaussian functions, that dene the functions of the atomic base, and the coecients of the LCAO expansion. We analyze the convergence characteristics of the HFGauss-GSA algorithm as a function of the parameters qV and qT , responsible for the behavior of the probability of visitation and "temperature"functions, respectively; and we realize that there is no ideal value for the pair (qV , qT ) that will ensure that the algorithm always converges. We performed HF calculations for the BH molecule with dierent spin multiplicities using the DZ atomic basis set presented here and the traditional DZ atomic basis set. With the obtained results, we constructed curves of the total energy versus the interatomic distance for this molecule. Calculations were also made to obtain multiple HF solutions for the BH system in order to analyze the possible changes introduced in the energy hypersurface.
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6
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CARLOS PIETRO CARDOSO LEAL GONÇALVES REBOUÇAS
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Singing in Time and Space: A Computational Model of the Evolutionary Dynamics of Passerines
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Líder : FLORA SOUZA BACELAR
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MIEMBROS DE LA BANCA :
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JOSE GARCIA VIVAS MIRANDA
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FLORA SOUZA BACELAR
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BRUNO VILELA DE MORAES E SILVA
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ELAINE CRISTINA CAMBUI BARBOSA
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Data: 23-jul-2019
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Resumen Espectáculo
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The songs of Passeriformes are long complex vocalisations produced by males in breeding season that have two mainly functions: attract a mate and defend the territory. This order are composed by two suborders, the Suboscines, that don’t have so much learning effect, and the Oscines, that exhibit socially mediated learning. The evolution of song in Passeriformes is a case of sexual selection by
female choice, however in the Oscines the social component of learning also influences the evolutio- nary process. On this work we make a model where the fitness isn’t explicitly calculated and depends
only of the own social dynamics, in a homogeneous environment with no geographical barriers. We consider three aspects of social dynamics: i) the process of selection of mate by female through song,
ii) the socially mediated learning of song by Oscines male offsprings and iii) the intraspecific compe- tition. For evaluate the results we build recognition networks, where the nodes represent the male and
female Passeriformes, and the edges represent the possible matings. We evaluated differences in the networks generated by Oscines and Suboscines in relation to the number of components, related to the phenomenon of speciation, and modularity, which we relate to the formation of common dialects to birds of the same community.
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7
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RUBICELY FRANCISCO DO NASCIMENTO
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STUDY OF SOLITONIC SOLUTIONS OF NONLINEAR PARTIAL DIFFERENTIAL EQUATIONS WITH THE USE OF THE HYROT METHOD
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Líder : GENILSON RIBEIRO DE MELO
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MIEMBROS DE LA BANCA :
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GENILSON RIBEIRO DE MELO
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HUMBERTO DE ALMEIDA BORGES
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LEANDRO HAYATO YMAI
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Data: 02-ago-2019
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Resumen Espectáculo
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The current work presents a study of the soliton solutions using the Bilinear Hirota Method for the integrable models of the non-linear equations of Korteweg and de Vries (KdV), modi ed Korteweg and Vries (mKdV) and Non-Linear Schrödinger (NLS ) in (1+ 1) - dimensions. We extend the KdV equations for (2 + 1) - dimensional models and and their soliton solutions. Also with the use of the Bilinear Hirota Method, we studied the dromions solutions of the KdV equation in (2 + 1) - dimensions and a graphical analysis was made from the obtained results, using the software MAPLE18.
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8
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LUAN ORION DE OLIVEIRA BARAUNA FERREIRA
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Testing Cosmologies with Dark Sector Interaction Using Redshift Space Distortion Data
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Líder : HUMBERTO DE ALMEIDA BORGES
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MIEMBROS DE LA BANCA :
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CARLOS ENRIQUE VALCARCEL FLORES
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CASSIO BRUNO MAGALHAES PIGOZZO
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FARINALDO DA SILVA QUEIROZ
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HUMBERTO DE ALMEIDA BORGES
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Data: 23-ago-2019
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Resumen Espectáculo
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Here we use the Chaplygin gas model decomposed in matter without pressure and vacuum energy to study the distortion in redshift space caused by the peculiar velocity of galaxies. Introducing baryonic matter into the equations that describe dynamics, we get the theoretical prediction of the fσ8 combination and show that its evolution depends on the vacuum energy density clustering model. Using the observational data for the redshift space distortion measurements fσ8, we performed a statistical test using the Monte Carlo Chain operating the Python MultiNest algorithm. Assuming that the vacuum density is homogeneous we find the best fit parameter set σ8(0) = 0.80 {+0.14 −0.11}, Ωm0 = {0.31+0.19 −0.17} and α = −0.05 {+0.64 −0.58}. By setting some values for the α parameter we find that such models are able to describe fσ8 data with the best fit Ωm0−σ8(0) growing to α < 0 and descending to α > 0.
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9
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JOSÉ RODRIGO BLANCO PELETEIRO
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DYNAMIC INVARIANTS, SCHWINGER FORMALISM AND A NEW VISION ON QUANTITIES CONSERVED IN QUANTIC MECHANICS
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Líder : MARIO CEZAR FERREIRA GOMES BERTIN
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MIEMBROS DE LA BANCA :
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CÁSSIUS ANDERSON MIQUELE DE MELO
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FREDERICO VASCONCELOS PRUDENTE
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MARIO CEZAR FERREIRA GOMES BERTIN
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Data: 13-sep-2019
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Resumen Espectáculo
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In this work we calculate dynamical invariants using the equations of motion of a quantum mechanical system and the Schwinger formalism. Both approaches turn out
to be complementary, the second being more fundamental than the first one. The cal- culations of the invariants are, initially, for the harmonic oscillator with time-dependent
frequency, for oscillators with higher dimension and, at the end, for the one dimensional
time-dependent, damped, driven harmonic oscillator. With the linear invariants associa- ted with the equations of motion and under the existence condition of solutions for the
diferencial equations of the parameters, it is possible to obtain a new way of canonical
quantization for the one-dimensional oscillator-type systems. This new procedure requi- res the identification of the linear invariants with ladder operators, which makes possible
to obtain the Hilbert space of the system.
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10
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ADEMIR DE JESUS SANTOS
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OBTAINING THE SHANNON ENTROPY FOR THE ATOM OF HYDROGEN CONFINED USING THE METHOD OF FINITE ELEMENT
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Líder : FREDERICO VASCONCELOS PRUDENTE
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MIEMBROS DE LA BANCA :
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ANA CARLA PEIXOTO BITENCOURT
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ELSO DRIGO FILHO
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FREDERICO VASCONCELOS PRUDENTE
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MARCILIO NUNES GUIMARAES
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Data: 30-sep-2019
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Resumen Espectáculo
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The present work implements computationally efficient numerical procedures to obtain Shannon Entropy for the Confined Hydrogen Atom . The procedures are based on the boundary variational formalism that uses the Finite Element Method (FEM) for the
expansion of the wavefunction in terms of base functions. Specifically, we use the p- version of the MEF which has as characteristic the ease of imposing the proper
boundary condition for the confined system. The conection of Information Theory and Quantum Theory was made possible through Shannon entropies in both position and moment spaces, as well as Entropic Sum . In particular, we make an analysis of these quantities, together with the eigenvalues of Energy, with the confinement radius for the confined hydrogen atom . A comparison between the confined hydrogen atom and a particle confined in a cage is made, especially for the quantity
, in order to analyze what happens in the rigorous confinement regime.
Results are compared with those in the literature, when available.
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11
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RAÍSSA SILVA FERNANDES
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Magnetic Fluid Hyperthermia: A Model of Temperature Diffusion Agents in Neoplastic Tissues
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Líder : JOSE GARCIA VIVAS MIRANDA
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MIEMBROS DE LA BANCA :
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JOSE GARCIA VIVAS MIRANDA
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ROBERTO LUIZ SOUZA MONTEIRO
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SUANI TAVARES RUBIM DE PINHO
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Data: 23-oct-2019
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Resumen Espectáculo
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Magnetic fluid hyperthermia (MFH) is a recent cancer treatment technique that has gained recognition for its effectiveness in preserving healthy cells. Its use is broad and advisable for tumors of low accessibility, as is the case of glioblastoma multiforme (GBM), the most frequent and aggressive brain tumor. Despite the studies done on MFH and GBM, the presented approaches have limitations, be they ethical, economic or technological. Therefore, the objective of this paper is to develop an agent-based computational model to emulate the diffusion of temperature in the neoplastic tissue medium submitted to the treatment of MFH, which may indicate new directions for treatment optimization.
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12
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RODRIGO NEVES DOS SANTOS
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“Magnetic Properties of KNaMSi 4 O 10 (M = Fe, Cu, Mn) Molecular Magneto under Hydrostatic Pressure Using First Principle Calculation”,
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Líder : JAILTON SOUZA DE ALMEIDA
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MIEMBROS DE LA BANCA :
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JAILTON SOUZA DE ALMEIDA
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ROBERTO RIVELINO DE MELO MORENO
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ALVARO SANTOS ALVES
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PEDRO PAULO DE MELLO VENEZUELA
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Data: 28-nov-2019
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Resumen Espectáculo
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Molecular magnets are materials with interesting properties: high magnetization, high remanence, among others. It has applications in areas such as magnetic recording, optical magneto, magnetic cooling, information and quantum computing. In this work we investigate the structural, electronic and magnetic properties of 3 molecular magnets that have the structural formula KNaMSi4O10 (M = Fe, Cu, Mn) using the theory of the exchange rate and correlation generalized gradient approximation (GGA) in the approximation of Perdew-Burke-Ernzerhof (PBE) with the electron-ion interaction given by PAW (projector augmented wave). The net parameters of the equilibrium are close to the experimental values with errors less than or equal to 1.7%. In addition, we obtained the derivative and bulk modulus of these materials - not yet calculated or measured for the manganese and iron compounds. In addition, we conclude that the copper compound is a metal, while the other materials are semiconductor. The magnetic nature of these materials has been correctly described. The magnetic coupling value was very close to the experimental with error less than 0.1% for manganese. Other coupling values gave errors around 20%. Investigation of the magnetic transition when the system is subjected to hydrostatic pressure has shown that manganese compound does not transition to the ferromagnetic state, while iron does not transition to the application of approximately 40 GPa and copper undergoes a transition in around 8 GPa.
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13
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HILDESON PAULO LESSA VIEIRA
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The interaction of bottomonium with a hadronic medium
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Líder : LUCIANO MELO ABREU
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MIEMBROS DE LA BANCA :
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LUCIANO MELO ABREU
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JORGE MARIO CARVALHO MALBOUISSON
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FERNANDO SILVEIRA NAVARRA
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Data: 05-dic-2019
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Resumen Espectáculo
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Heavy mesons play an important role in understanding strongly interacting matter. Quarkonia (such as charmonia and bottomonia) that survived the plasma phase of quarks and gluons are expected to collide with other particles that make up hadronic matter. In this paper, we present a study on the interactions of the Upsilon meson with a hadronic medium. The meson-meson interactions are described by an effective lagrangian that is based on a theory of chiral perturbation extended to SU (4) symmetry, which gives the amplitudes of unitarized coupled channels projected in s-waves. The symmetry is explicitly broken for SU (3) by suppressing the meson-driven interactions consisting of quark b. We calculate the shock sections for scattering by pseudo-scalar and vector mesons, as well as their inverse processes. Maintaining the validity of this current approach in the low energy CM range, the most relevant channels are evaluated.
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Tesis |
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1
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THIAGO DA CRUZ FIGUEIREDO
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Complexity in control and planning of human movement
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Líder : JOSE GARCIA VIVAS MIRANDA
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MIEMBROS DE LA BANCA :
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CLEBER LUZ SANTOS
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ELEN BEATRIZ CARNEIRO PINTO
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JOSE GARCIA VIVAS MIRANDA
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RAPHAEL SILVA DO ROSARIO
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ROBERTO FERNANDES SILVA ANDRADE
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Data: 08-mar-2019
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Resumen Espectáculo
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Abstract: Several studies have shown evidence of complex behavior in the human nervous system. Despite the complex and highly variable architecture of the nervous system, humans present motor behaviors that are consistent across subjects and even across tasks. This indicates that underlying optimization principles are at work, which are responsible for dealing with many degrees of freedom and with the intrinsically non stationary nature of sensory inputs. In this study a control model for upper-limb trajectories is presented, which is based on the segmentation of complex movements in movement elements that maximize smoothness and minimize movement duration. It is shown that such a model can account for the movement patterns of several arm reaching and drawing tasks in healthy subjects, as well as for the strategies of optimization involved in learning a new motor task. Furthermore, experimental evidence indicates that the complex properties that characterize the model are an effect of the motor planning process, as opposed to a trivial consequence of the biomechanical constraints involved in the movement. The results open new possibilities for monitoring the evolution of subjects along the rehabilitation and motor learning process.
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2
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RICARDO MARTINHO LIMA SANTIAGO PEREIRA
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Supersymmetric Relativistic Simplistic Quantum Mechanics.
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Líder : JOSE DAVID MANGUEIRA VIANA
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MIEMBROS DE LA BANCA :
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LOURIVAL MANOEL DA SILVA FILHO
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MILTON SOUZA RIBEIRO
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RONNI GERALDO GOMES DE AMORIM
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MARCO ANTONIO SILVA TRINDADE
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JOSE DAVID MANGUEIRA VIANA
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Data: 28-mar-2019
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Resumen Espectáculo
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Relativistic symplectic quantum mechanics (RSQM) considers a noncommutative algebra of functions on a phase space G=(q,p) and an associated Hilbert space H_{G} to construct a unitary representation of the Poincaré group Lie algebra. Then, Klein-Gordon and Dirac equations are obtained in terms of phase space variables, and the Wigner function can be derived directly from the solutions of these equations. In this formulation, the operators Q and P are given by Q=q*=q + (ih/2)(d/dp) and P=p*=p - (ih/2)(d/dq). Solutions for the Klein-Gordon and Dirac equations with potentials required special treatment: for that, we extend in this work the method of supersymmetric quantum mechanics (SUSYQM) to RSQM. Using a hierarchy of Hamiltonians, we obtain exact solutions for some potentials. By taking a general expression for vector and scalar potentials in terms of appropriate parameters, we analyze a potential (-A/Q), the Dirac harmonic oscillator, and a potential added to mass term. Spectra of eigenvalues, the correspondent eigenfunctions (quasi-probability amplitude in phase space) and Wigner functions are derived and discussed.
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3
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BALBINO JOSE DA SILVA POMPONET FILHO
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Study of Bäcklund Transformations for Hierarchies KdV and mKdV
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Líder : GENILSON RIBEIRO DE MELO
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MIEMBROS DE LA BANCA :
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ADEMIR EUGENIO DE SANTANA
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CARLOS ENRIQUE VALCARCEL FLORES
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ESDRAS SANTANA DOS SANTOS
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GENILSON RIBEIRO DE MELO
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HUMBERTO DE ALMEIDA BORGES
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JOAO DE AZEVEDO CARDEAL
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Data: 28-jun-2019
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Resumen Espectáculo
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In this thesis we present a study of the Bäcklund transformations for the hierarchies Korteweg - de Vries (KdV) and modied Korteweg - de Vries (mKdV). We show that it is possible to obtain a auto-Bäcklund transformation valid for all the equations that make up the KdV and mKdV hierarchies. For this, we use the Riccati system associated with each hierarchy and demonstrate, by mathematical induction, that it remains invariant under a given transformation. In addition, we use the auto-Bäcklund transformation to obtain the soliton solutions and the non-linear superposition formulas of each hierarchy.
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4
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JOSENILTON DO NASCIMENTO SOUSA
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Theoretical-Experimental Study of Selection of Photoionization Shock and Photoabsorption of Heterocyclic Organic Molecules in Vacuum Ultraviolet Region
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Líder : FREDERICO VASCONCELOS PRUDENTE
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MIEMBROS DE LA BANCA :
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FREDERICO VASCONCELOS PRUDENTE
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LUIZ ANTONIO VIEIRA MENDES
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VICTOR MANCIR DA SILVA SANTANA
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MILTON MASSUMI FUJIMOTO
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ANA LUCIA FERREIRA DE BARROS
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Data: 29-ago-2019
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Resumen Espectáculo
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nderstanding the evolutionary process of the universe, from the formation of simple molecules to more complex molecules, has been a topic widely discussed in the scientific community. In astrobiology it is believed that cyclic organic compounds may have played an important role in the evolution of life on earth, having important prebiotic functions. One way to quantify photochemical processes is by determining of the photoabsorption shock section. Particularly, the knowledge of the absolute absorption shock section for complex polyatomic species generally permeates a certain experimental action. In this context, we performed an experimental investigation of photoabsorption and photoionization processes through the interaction of synchrotron radiation in the vacuum ultraviolet region in heterocyclic organic molecules in the gas phase. Specifically, we are interested in studying the simplest 6- and 5-membered fundamental molecules, namely Pyridine, Pirrol, Furano and Thiophene, for their importance in understanding the synthesis of more complex cyclic species in the interstellar medium. The measures Experimental experiments were performed at the National Synchrotron Light Laboratory, Campinas-SP, using the technique of the Dual Ionization Chamber. With this technique it was possible to measure the photoabsorption shock sections from the first ionization threshold up to 21.5 eV, and the quantum photoionization efficiency. Photoionization and decay shock sections neutral scale were then derived from this data. In addition, a theoretical study was performed using Schwinger's Iterative Variational Method (SVIM) and the PolyScat computational package to calculate Pirrol's photoionization shock section. Additionally, the absolute partial photoionization shock (PICS) section was determined for each fragment of Pyridine, from the product of the photoionization shock section (oi) with the respective relative productions of the different ions. The sum rule was also used to calculate the static polarization value of electric dipole for these molecules. Comparisons are made with experimental and theoretical data available in the literature.
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5
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EDUARDO MOREIRA DAMASCENO
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STUDY OF CYANACEACETILEN RADIOLYSIS AND ITS MIXTURES WITH CARBON MONOXIDE, CARBON AND METHANE, INDUCED BY IONS IN THE ME V.
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Líder : LUIZ ANTONIO VIEIRA MENDES
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MIEMBROS DE LA BANCA :
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DENIS GILBERT FRANCIS DAVID
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ENIO FROTA DA SILVEIRA
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LUIZ ANTONIO VIEIRA MENDES
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MARIA LUIZA ROCCO DUARTE PEREIRA
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ZENIS NOVAIS DA ROCHA
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Data: 02-sep-2019
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Resumen Espectáculo
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The present work aims at study the cyanoacetylene condensed gas radiolysis (HC3N), and their respective mixtures with carbon monoxide (CO), carbon dioxide (CO2) and methane (CH4), also evaluate the mixtures interacting with energetic ions (MeV). This analysis intent to simulate and study the physico-chemical properties of interactions similar to those induced by energetic cosmic rays in dense and cold astrophysical environments, for this we use FTIR
and PMDS-TOF techniques. Measurements were performed using an electrostatic accelera- tor of the Van de Graaff type, situated found Pontifical Catholic University at Rio de Janeiro
(PUC-Rio). This accelerator is capable of generating electrical potentials up to 4 MeV and pro- duce ionic beams with a current range between nano to microampère. For this investigation we
used the infrared technique with Fourier Transform, where through the generated spectra we determined the sections of apparent shock of creation and destruction, stopping power, medium intensity fluency, among other physical quantities of interest. The samples were also analyzed
by the PDMS-TOF plasma desorption time-of-mass spectrometry technique using a mass spec- trometer also belonging to the Van de Graaff Accelerator Laboratory of PUC-Rio, using this
technique we analyzed the spectra obtained from desorption produced on the surfaces of the cyanoacetylene condensate sample (HC3N), and its respective mixtures with (CO), (CO2) and (CH4), obtained through the fission fragments of 252Cf.
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6
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WANDERSON SILVA DE JESUS
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ION–RARE-GAS MICROSOLVATION STUDIES BY EMPLOYING AN EVOLUTIONARY ALGORITHM
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Líder : FREDERICO VASCONCELOS PRUDENTE
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MIEMBROS DE LA BANCA :
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FEDERICO PALAZZETTI
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FREDERICO VASCONCELOS PRUDENTE
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JADSON CLAUDIO BELCHIOR
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JORGE MANUEL CAMPOS MARQUES
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MANUELA SOUZA ARRUDA
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TIAGO VINICIUS ALVES
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Data: 20-sep-2019
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Resumen Espectáculo
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The microsolvation has been subject of intense theoretical and experimental study
with implications in diverse areas such as atmospheric chemistry, biological processes, per- meation and transport membrane, among others. Therefore, this thesis aimed to develop a
study of the microsolvatation of ions through noble gases. One of our specific goals is to survey the microsolvatation of ion Li+by argon, kripton and mixture of these atoms. For this
construction, analyses involving the interaction construction of two and three-bodies metal- alkaline ions with noble gases, from the fitting of potential functions ab initios on the eletronic
energy using the methodology CCSD(T). The determination of stable clusters structures will be given by the application of the evolutionary algorithm (EA). The evolutionary algorithm will search of these low energy structures, both in global and local minima. In order to strengthen this study, pos-optimization calculations using the ab initios CCSD(T) and MP2 methods are also performed. Treatment of clusters with noble gases of higher numbers, a DFT methodology is also used in the stage of pos-optimization, with the goal to perform a
Benchmark analysis of these systems. Lastly, from diverse local minima generated by evo- lutionary algorithm we applied a Machine Learning technique to enable the determination
of choose rules of the better EA minima that present an efficient description of the energy landscape from the clusters length.
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7
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BELIATO SANTANA CAMPOS
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STUDY BY INFRARED TECHNIQUE OF CONDENSED CO2 RADIOLYSIS AT DIFFERENT TEMPERATURES, INDUCED BY ENERGY IONS OF H +, HE + AND N +
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Líder : LUIZ ANTONIO VIEIRA MENDES
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MIEMBROS DE LA BANCA :
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ANTONIO FERREIRA DA SILVA
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CARLOS EDUARDO FELLOWS
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CLAUDIO HANASHIRO BARBOSA SILVA
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DIANA PAULA DE PINHO ANDRADE
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LUIZ ANTONIO VIEIRA MENDES
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Data: 28-nov-2019
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Resumen Espectáculo
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The research developed in this doctoral work describes the study of CO2 molecule radiolysis by energetic ions, whose results present contributions to works performed with astrophysical ice. For this, experiments were carried out, which can be observed in light of simulations of interactions that occur in astrophysical environments, once the CO2 molecule was irradiated in condensed phase (at different temperatures, between 10 K and 75 K), with different projectiles (H +, He + and N + ions), whose energies ranged from 1.7 to 2.0 MeV. The in situ analysis was made possible by the infrared absorption technique using a Fourier transformed spectrometer. From the analysis of infrared absorption curves, shock sections were assigned from a radiolysis process (destruction - σd and creation - σc). For 2 MeV at 10 K, σd = 5.0 x 10-14 cm2, while for H + with the same energy at 75 K, σd = 8.7 x 10-14 cm2. The other ions (He + and N +) followed the same trend: the higher the temperature, the greater the apparent destruction section of the molecule, obeying an empirical function of the kind. It was also observed that the destruction of CO2 causes the formation of new species in the ice condensate CO2, being CO, CO3 and O3, having 75 K as the most efficient temperature for radiolysis processes. This trend was also repeated for the heavier ions (He + and N +). From the shock section values in relation to the Stopping Power (Se) it was obtained its variation with the temperature, according to the power law, with parameter values between 0.73 and 1.9. In addition, a study of the band displacement of the CO2 molecule and its fragments was performed. Another result was the determination of Sputtering dependence (Y) as a function of temperature (T) and energy transferred by the projectile, Stopping Power (Se), Y = Yo + A. Se (0.1 + B.T). exp (T / C). Another issue analyzed was the medium intensity flux. Through this flux, it is possible to estimate the speed of processes induced by these energetic beams in different regions of the MI.
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8
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ALEXSANDRO RICARDO DA SILVA
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PREPARATION OF THIN AMINO ACIDS FILMS BY WPS AND EFFECTIVE CELL, WITH CHARACTERIZATION VIA FTIR AND MEV, FOR DETERMINATION OF THE OPTICAL CONSTANT.
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Líder : ROBERTO RIVELINO DE MELO MORENO
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MIEMBROS DE LA BANCA :
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FERNANDO DE BRITO MOTA
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JAILTON SOUZA DE ALMEIDA
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JOSE DAVID MANGUEIRA VIANA
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ROBERTO RIVELINO DE MELO MORENO
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SERGIO ANDRE FONTES AZEVEDO
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TIAGO VINICIUS ALVES
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Data: 04-dic-2019
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Resumen Espectáculo
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In this work, we have theoretically proposed Creutz-Taube coordination complexes, with formulae [(HN 3 ) 5 -Co-py-X-py-Ru-(NH 3 ) 5 ] q+ , assuming different ionic charges, q, and spin multiplicities, compatible with the metal ions involved and with X = C≡C and C 60 . The main aim was to replace the central part of the bridge ligand between Co and Ru ions with a C 60 molecule. From electronic structure calculations within the scope of the Density Functional Theory (DFT), we have performed a systematic computational- theoretical investigation to examine the new coordination complexes. It is of both theoretical and experimental interest to investigate the electronic properties of coordination complexes containing mixed valence, aiming at potential technological applications. In this context, we have also investigated the feasibility of using fullerene- containing ligands in the coordination complexes to control electronic excitations and transfer between metal centers with different oxidation states. Our calculations allowed us to assess whether fullerene can facilitate or hinder electron relocation between two metal centers. In order to make our computational simulations possible, we use start with a typical geometry occurring for these types of complexes, with crystallographic data available in the literature. In addition, we have performed a study of a standard complex (containing -C≡C- in the bridge ligand) to compare our results with the new proposal containing C 60 . In this sense, as generally as possible, we investigated several theoretically acceptable possibilities for the C 60 fullerene-mediated coordination complexes (Creutz-Taube-type) and Co n+ and Ru m+ metal ions in their different oxidation states and spin multiplicities. In summary, our main model systems were described by the formulae [(NH 3 ) 5 Co-py-C 60 -py-Ru(NH 3 ) 5 ] q+ (q = 4, 5 and 6; q = n + m). As is known, such complexes constitute a motivating theoretical challenge, since the investigation of their electronic properties allows a detailed analysis of the essential properties for the electronic transport between the metallic centers, as well as for the understanding of the electronic spectroscopy of these complexes. Thus, we could infer about the valence tautomery mechanism in the case of the [(NH 3 ) 5 Co-py-C 60 -py-Ru(NH 3 ) 5 ] 5+ complex. Finally, we have established a systematic analysis of the electronic properties as well as the influence of C 60 on the valence tautomerism and electronic properties in general.
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9
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EDWIN EDGAR MOZO LUIS
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Determination of local roughness exponent in nonlinear molecular beam epitaxy class models
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Líder : THIAGO ALBUQUERQUE DE ASSIS
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MIEMBROS DE LA BANCA :
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ERNESTO PINHEIRO BORGES
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FERNANDO ALBUQUERQUE DE OLIVEIRA
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FERNANDO DE BRITO MOTA
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SUKARNO OLAVO FERREIRA
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THIAGO ALBUQUERQUE DE ASSIS
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Data: 06-dic-2019
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Resumen Espectáculo
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The growth of out-of-equilibrium interfaces via computer simulation is of high relevance for investigating microscopic phenomena, for example, the role of atom diffusion in terraces and cluster perimeters. In addition, finding a set of scaling exponents allows us to classify interfaces within a universality class. If a normal surface roughness scale is observed, determining the global roughness exponent is equivalent to finding the local roughness exponent. Some results reported in the literature, obtained using computer simulations on models that are said to belong to the Villain-Lai-Das Sarma class (VLDS), suggest that the global roughness exponent is distinct from the local roughness exponent, which may lead to conclusions on which asymptotic anomalous scale exists in the VLDS class. Such feature may be justified by the global roughness exponents larger than the unit. In this thesis, we introduce a method for measuring local height fluctuations in interface, based on calculating the shortest distance from a profile point to a polynomial of degree adjustment n. The method is named the Optimal Fluctuations Analysis. (ODFAn ). We make a comparison with the method based on Detrended Fluctuations Analysis (DFAn ) and the standard local roughness method (DFA 0 ). The goal is to extract the local roughness exponent about profiles/surfaces generated by network models deposition, namely: Growth in a Restricted Solid-on-Solid model (CRSOS), (Das Sarma and Tamborenea-DT) and (Clarke Vvedensky-CV), believed to belong the VLDS class. We observe that these models present a transient regime in which profiles/surfaces have characteristic length (hill structures). For estimate the average lateral length of the hills, the value of the first zero or minimum of the normalized height-height auto-correlation function was used. Our results for the local roughness exponent extracted with the ODFA n method are compatible with the calculated exponent, using the group renormalization theory with first and second loop corrections for the VLDS class. For the CRSOS and DT models, the latter considering a situation where the noise reduction technique is applied in d = 1 dimensions and for the CV model, with d = 1.2 dimensions, we will use a polynomial adjustment with n = 1.2. A better scaling is observed for n = 2, where the effective local roughness exponents were extracted to scale lengths of the same order as the average lateral length of the hills. In the CV model at d = 2, an anomalous scale transient was investigated for small scales, calculating local roughness. Because it is a more realistic model for thin film growth simulation, we also study the distribution of the average number of steps, Np , of surface adsorbed atoms with the CV model, as a function of the parameters R and ε, where R is the ratio between the diffusion rate, D0 (considering atoms without side neighbors) is the deposition rate F, and ε is the parameter associated with the probability of detachment of atoms with their lateral neighbors. Our results show distributions in the form of extended exponentials under the low temperature regime. In the high temperature regime our results indicate that the average number of steps scales with Rε² , suggesting that when detachment from kink sites becomes possible, there is a large amount of displacement of atoms that control Np.
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10
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VINÍCIUS NONATO ALVES LULA ROCHA
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An Algebraic Formulation of Relative Quantum Mechanics and Quantum Field Theory
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Líder : JOSE DAVID MANGUEIRA VIANA
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MIEMBROS DE LA BANCA :
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JOSE DAVID MANGUEIRA VIANA
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MARIO CEZAR FERREIRA GOMES BERTIN
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MARCO ANTONIO SILVA TRINDADE
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JOSE ABDALLA HELAYEL NETO
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ADEMIR EUGENIO DE SANTANA
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Data: 19-dic-2019
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Resumen Espectáculo
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We present in this dissertation some new results for the development of the relativistic quantum theory within the algebraic approach proposed by Schönberg and developed latter by Bohm, Hiley, Fernandes and Vianna and other autors. Firstly, by exploring the DKP equation in the Bohm, Hiley, Fernandes and Vianna’s approach we have shown its equivalence with the Klein-Gordon-Fock equation and the Proca equation; we also have shown this algebraic formalism extend naturally the Kruglov approach of the non-massive DKP equation including the 0-spin case. In the sequence we extend Schönberg’s formalism to obtain DKP algebra by introducing a method, via equivalence class, to extract the ParaDKP algebra (PDKP algebra) of the symplectic Clifford algebra of phase space; in consequence of this methodology we have found symplectic versions of Klein-Gordon-Fock like, Dirac like and DKP like equations. We also have developed a superalgebra in which bosons and fermions are handled in a unified way and we have shown how to extract from this algebra the Clifford superalgebra and the DKP superalgebra. In this approach we proposed Klein-Gordon-Fock like, Dirac like and DKP like superequations. Finally we have shown how the quantum field theory could be included in this formalism by using the distributions and algebra bundles mathematical structures.
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