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Item Propriedades elétricas de cadeias de poliacetileno fluoretadas(Universidade Federal de Goiás, 2015-08-02) Abreu, Leonardo Martins de; Fonseca, Tertius Lima da; http://lattes.cnpq.br/8193800922148980; Fonseca, Tertius Lima; Gargano, Ricardo; Braghin, Fábio LuisUsing Hartree-Fock (HF) and the second-order Møller-Plesset perturbation theory (MP2) methods with the 6-31G(d) basis set, we have investigated the chain length dependence of the dipole moment, linear polarizability, first and second hyperpolarizabilities of fluorinated polyacetylene chains (PFHA). Such properties were calculated using converged geometries obtained at the HF/6-31G(d) e MP2/6-31G(d) levels theory. The converged geometric parameters were obtained from equilibrium geometry of the oligomer with 40 carbon atoms. Our results show that the dipole moment and the first hyperpolarizability grow initially and exhibit a saturation pattern with the size of chain. In opposition, the linear polarizability and second hyperpolarizability present an increase with increasing chain length. It is found that the effects of electron correlation have an important role on the equilibrium geometry and on the electric properties. For the first hyperpolarizability, in particular, the asymptotic value including the electron correlation effects is 17 times larger than the uncorrelated one. These calculations were performed using the GAUSSIAN03, GAUSSIAN09 and Finito.f programs.Item Estudo teórico de propriedades elétricas de derivados de retinal em solução(Universidade Federal de Goiás, 2011-03-03) Adriano Júnior, Luizmar; Fonseca, Tertius Lima da; http://lattes.cnpq.br/8193800922148980; Fonseca, Tertius Lima da; Chaudhuri, Puspitapallab; Maia, Lauro June QueirozIn this work we study the dipole moment, linear polarizability and first hiperpolarizability of 09cis, 11cis, 13cis and all-trans retinal derivatives in the gaseous phase and in different solvents. The solvent effects were modelled using the sequential Quantum Mechanics/Molecular Mechanics – S-QM/MM – methodology and the electric properties were calculated numerically with the finite field method. We use an average solvent electrostatic configuration – ASEC – to obtain the same statistical average with just one quantum mechanics calculation, instead of performing several quantum mechanics calculations for each one of the configurations of liquid. The second-order Møller–Plesset perturbation theory – MP2 – were used to describe the electronic structure. Our results show that the presence of the solvent increases the first hyperpolarizability of molecules of retinal [retinoic acid] by 17%-120% [5%-65%] when compared with corresponding gas phase results. It is found, in addition, that the dipole moment and the first hyperpolarizability are particularly affected by changes in the polarity and nature of solvent. A comparative analysis between cis and trans retinal derivatives shows that the isomerization effects have a marked influence on both the dipole moment and the average first hyperpolarizability.Item Análise comparativa da eficiência fotodinâmica de fotossensibilizadores em sua forma base livre e formando complexados com zinco(Universidade Federal de Goiás, 2014-04-09) Alonso, Lais; Gonçalves, Pablo José; http://lattes.cnpq.br/0515343409614452; Gonçalves, Pablo José; Borissevitch, Iouri; Bakuzis, Andris FigueiroaPhotodynamic therapy (PDT) is a technique that has been increasingly used in cancer treatment. It consists in introduce a photosensitizer (PS) in cancerous tissue and irradiate it with light in the visible range. Targeting a more effective treatment of PDT, currently there are several studies on the efficacy of these PS. In this work, we studied the photodynamic efficiency seven PS: meso-tetrametilpiridil, meso-tetrasulfonatofenil and carboxiftalocianinas with their base free or metallated with zinc atom in its center ring and protoporphyrin IX. Erythrocytes suspended in 2 to 10% hematocrit were treated with or without 25 μM of PS were exposed to light from a halogen lamp, and measured the time required to obtain 50 % hemolysis (T1/2). To examine whether the photodynamic efficiency is related to the affinity of PS by membrane, we performed measurements of the octanol/water partition coefficient (PO/W) of each PS. Our results indicated that the PS studied were very hydrophilic and showed a trend for greater photodynamic efficiency the PS with higher Log PO/W. To better understand the mechanism of action of the studied PS the degree of lipid peroxidation in erythrocyte membranes irradiated with PS was assessed by measuring the formation of malondialdehyde (MDA) and a correlation between the rate of peroxidation and hemolytic potential was found. The ability of PS to degrade proteins was assessed using bovine serum albumin (BSA), monitoring the fluorescent signal of this protein into solution and under irradiation in the presence of PS.Item Éxcitons em semicondutores magnéticos diluídos(Universidade Federal de Goiás, 2006-08-02) ALVES, Erivelton de Oliveira; SOUZA, Márcio Adriano Rodrigues; http://lattes.cnpq.br/2980610890056479We investigate the resonant tunneling of electrons and holes in an asymmetric double quantum bit CdTe / CdMnTe in the presence of electric and magnetic fields applied along the growth direction. We show that in this case it is possible to achieve a condition of simultaneous resonant tunneling of electrons and holes with spin set, ie, a resonant tunneling of excitons polarized. Then we calculated the excitonic binding energy as a function of applied fields, showing the strong dependence of the binding energy with the tunneling of carriers. The electronic structure was calculated using the k ~ ~ p multiband Kane model. The eigenstates were obtained by solving numerically the equations ° C ~ the effective mass using the method of inverse power. The effects of lattice strain were treated by the Bir-Pikus model. The energy calculation of excitonic Dial-Up was conducted using the variational method. We consider the perfectly abrupt interfaces of the heterostructures, ie effects of enlargement of the interfaces were neglected.Item Dinâmica populacional em sistemas atômicos de dois e três níveis de energia(Universidade Federal de Goiás, 2017-08-10) Alves, Eyber Domingos; Almeida, Norton Gomes de; http://lattes.cnpq.br/3182841849332242; Oliveira, Guilherme Colherinhas de; Almeida, Agnaldo Rosa deIn this work a description of the interaction between electromagnetic radiation and matter will be made. Two and three-level atomic systems will be addressed, which in turn is in the (Lambda) configuration.We will use the Dicke states to calculate the transition probability between the energetic levels for a 2-level ensemble of atoms interacting with a circularly polarized field. We will deduce the master equation for a two-level atom interacting with a thermal reservoir, observing the effects of irreversible spontaneous decay and loss of coherence between quantum states. Finally, we will study the phenomenon of Electromagnetically Induced Transparency (EIT) and Dark states.Item Landauer principle in the context of relativistic communication theory(Universidade Federal de Goiás, 2023-04-25) Alvim, Yuri de Jesus; Céleri, Lucas Chibebe; http://lattes.cnpq.br/6630683190018665; Céleri, Lucas Chibebe; Vanzela, Daniel Augusto Turolla; Pereira, Rômulo Cesar RougemontThis monograph aims to investigate Landauer's principle for a quantum system in a relativistic context. Specifically, we consider a communication channel described by a mode of a quantum field in a curved spacetime. In order to accomplish that, an introduction to Shannon's theorems, as well as some very important concepts in information theory, will be first presented. The relativistic spacetime structure will be described in the sequence, such that the quantum field theory can be used, in this context, to describe the communication channel. Lastly, the calculation of the channel capacity and the energy contributions for the transmission of information over such a channel will be done. Such calculations provide three different contributions to the total energy variation of the system: one due to the change in the spacetime, one associated with the work necessary to switch on or off the interaction between the detectors ---qubits employed to read and codify the information--- with the field and, finally, the last one which is due to the communication process itself. This third contribution vanishes for the considered communication channel, so that no extra energy cost is needed to transmit information once the states of the qubits are settled. The original contribution of this work enters here by considering the cyclical conversion of the transmitted information into work. Since no energy is transferred from the sender to the receiver, this engine apparently violates the second law of thermodynamics. By employing Landauer principle we find the energy contribution which allows the receiver to convert information into work without contradictions with thermodynamics.Item Estudos da sinterização de Bi12TiO20 (BTO) visando obter cerâmicas transparentes(Universidade Federal de Goiás, 2011-02-16) AMARAL, Thiago Martins; CARVALHO, Jesiel Freitas; http://lattes.cnpq.br/5841291496427516This work presents the systematic results of studies concerning the sintering of the Bi12TiO20 (BTO) aiming the production of transparent ceramic samples. All that because the BTO is a material that has great scientific and technologic visibility due to its optical, electro and electro-optical properties, but still little explored as ceramic. The sintering starting material was obtained by solid state reaction between Bi2O3 e TiO2; the synthesized BTO was grinded in ball milling until sub micrometric sizes. The conditions for preparing green samples were also investigated, allowing samples with green relative density between 58% and 62%, with uniaxial and isostatic pressing techniques. The study of the sintering process involved different sintering programs, under different atmospheres conditions and additive utilization. Optimized conditions were established and the limiting factors discussed. The quality of the obtained ceramics was assessed by their final relative density, phase homogeneity, microstructure and optical properties (transmission, optical activity and electro-optical performance). Samples with relative density above 99,9% and 50% of the monocrystal´s optical transmission in the 633 nm wavelength and equal optical activity were obtained. Nevertheless, the ceramics still show scattering centers and none liquid electro-optical effect was observed.Item Efeitos de terpenos nas membranas de estrato córneo estudados por ressonância paramagnética eletrônica(Universidade Federal de Goiás, 2008-02-18) Anjos, Jorge Luiz Vieira dos; Alonso, Antônio; http://lattes.cnpq.br/5013069863616789The interaction of the skin penetration enhancers DL-menthol, -terpineol, 1,8-cineole and (+)-limonene with membranes of the uppermost skin layer, the stratum corneum (SC) and with multilamellar vesicles from 1,2-dipalmitoyl-sn-glycero-3-phosphaticylcholine (DPPC)is investigated by electron paramagnetic resonance (EPR) spectroscopy using spin-labeled analogs of androstanol ASL),stearic acid (5-DSA), methyl stearate (5-DMS) and a small spin label 2,2,6,6-tetramethylpiperedine-1-oxyl (TEMPO). The terpenes were added to SC samples using ethanol as a co-solvent (20% ethanol in the buffer), the effect of ethanol on the SC also was investigated. The spectra of spin labels ASL, 5-DSA and 5-DMS in the membranes of SC are characterized by the presence of two spectral components differing in mobility.Component 1 was attributed to the spin labels H-bonded to the headgroups, while component 2 was assigned to the spin labels H-bonded to water molecules or temporally non-hydrogen-bonded. EPR results showed that ethanol in the range 0-70% did not alter the fluidity in SC membranes or the relative fractions of these two components. Instead, ethanol only caused a selective extraction of spin labels, indicating that ethanol acts as extractor and not as fluidizer when facilitates molecular permeation in the skin. Addition of 1% DLmenthol to the solvent containing 20% ethanol increases both the mobility and the fraction of spin labels in the component 2 (more mobile spectral component). Similarly, with the addition of 1,8-cineole, the spin probes were gradually transferred from the motionally more restricted component 1 to the more mobile component 2. The spectrum of the spin label TEMPO in the membranes of SC allows for the determination of the actual partition coefficient and rotational diffusion rates of the spin probe in the aqueous and hydrocarbon environments. The enthalpy changes,H°,to transfer the spin probe from the aqueous to the hydrocarbon phase, as well as the activation energies associated to its rotational motion, were considerably smaller for SC when compared to DPPC, indicating less pronounced thermal reorganizations for SC samples. For DPPC,all terpenes increased both the partition coefficient and the rotational diffusion rate of the spin label in the membrane, except in the liquid-crystalline phase. These results suggest that the terpenes,effectively acting as spacers in the membrane,fluidize the lipids and cause ruptures in the hydrogen-bonded network of the membrane-water interface, with consequent displacements of spin probes towards the hydrophobic core. The EPR spectra of maleimide derivative spin label (6-MSL)covalently attached to stratum corneum proteins indicate that 1,8-cineole does not alter the dynamics of protein backbones.Instead, this terpene only increases the solvent s ability to dissolve and mobilize the nitroxide side chain, which is in agreement with its low irritation response.Item Tratamento de sistemas abertos via reservatórios térmicos bosônico e fermiônico(Universidade Federal de Goiás, 2019-04-15) Araújo, Dannilo Iágor Evangelista de; Almeida, Norton Gomes de; http://lattes.cnpq.br/3182841849332242; Almeida, Norton Gomes de; Colherinhas, Guilherme; Almeida, Agnaldo Rosa de; Cardoso, Wesley Bueno; Sales, José de SousaWe developed this work at the moment with the objective to resolver the master equation for both thermal reservoir: bosonic and fermionic, as well as the master equation in reservoirs of vacuum and of Fock compressed . the bosonic thermal reservoir is modeled by a collection of coupled harmonic oscillators and the fermionic reservoir by a collection of two-level atoms. We made use of the Jaynes-Cummings model and the Bohr, Bohr-Markov and Markov approaches. In the end we discussed the application to the master equation for two distinct phenomena, Cooling by Heating (CBH) analyzing average energy graphs to the atomic system versus number of photons, and the average energy of the bosonic system as a function of the mean number of phonons, we observed the negative temperature in the absolute scale due to the inversion of population of states in function of cooperativity, we also analyzed a signature of negative response in a three level system interacting in a optical cavity, that comes as a result of decrease in the output field intensity when the input field intensity is increased.Item Síntese, caracterização e magnetohipertermia de ferritas de manganês Mn1-xAxFe2O4 dopadas com cobre, magnésio ou cobalto(Universidade Federal de Goiás, 2017-07-12) Araújo, Marcus Vinicíus; Bakuzis, Andris Figueirôa; http://lattes.cnpq.br/3477269475651042; Bakuzis, Andris Figueirôa; Coaquira, José Antônio Huamaní; Santos, Marcus Carrião dos; Silva, Sebastião Willian da; Bufaiçal, Leandro Félix de SousaNanoparticles based on Mn-ferrite, Mn1−xAxFe2O4, doped with copper, magnesium and cobalt (A = Cu, Mg ou Co) were synthesized by hydrothermal method under pressure, with X varying from 0 to 0, 5. Magnetic fluids stable in physiological conditions were obtained surface-coating the nanoparticle with citric acid. X-ray diffraction confirmed the spinel structure. Energy dispersive spectroscopy (EDS) confirmed the success of the synthesis of the mixed ferrite, where the element composition agreed with the value expected within an error of 10%. Transmission electron microscopy showed sphericalshaped nanoparticles, while magnetization data at room temperature allowed the analysis of the coercivity field (Hc) and the saturation magnetization (Ms). Ms decreased with the increase of X for the Cu and Mg doped samples, while the opposite effect was observed for Co doped nanoparticles. Hc increased the higher the X value for all the samples. The effect on the Cu and Mg-doped ferrites are explained by the increase in particle size. However, the Co-doped samples, showed a diameter increasing the higher X, but Hc also increased. In this case the Hc behavior is explained by the increase concentration of Co and its effect on the magnetic anisotropy which increases for higher Co content. The magnetic hyperthermia efficiency of the magnetic fluids, for all samples, were investigated in a field amplitude ranging from 50 Oe to 170 Oe and frequencies from 110 kHz up to 990 kHz. The hyperthermia efficiency decreased with X increasing, considering the case of 130Oe and 333 kHz, which indicates that at this experimental condition undoped Mnferrite nanoparticles are better for hyperthermia. In most of the samples it was observed that the efficiency scaled with the square of the field amplitude, which is in accordance with Linear Response Theory (LRT). In addition, the hyperthermia frequency dependence study showed a saturation effect, for some samples, at a frequency higher than 600 kHz. The experimental data as function of frequency were susccessfully curve fitted with the LRT model using 2 free parameters related to the effective relaxation time ( ef ) and the equilibrium susceptibility ( 0). In particular, for theMn-ferrite sample for a field of 130Oe it is found ef = 5, 2 · 10−7s and 0 = 0, 028. The value of ef can be explained using an effective magnetic anisotropy value of 2·105 erg/cm3. The value is one order of magnitude higher than the bulk value, and allowed one to estimate the surface anisotropy contribution to in the order of 0, 04 erg/cm2. On the other hand, a linear chain formation model, for this sample consisted of a trimer (3 nanoparticles), can also explain the increase of the effective anisotropy. Moreover, we found a 0 value lower than the estimated Langevin susceptibility. In order to explain this, a new model, valid in the linear regime, was developed considering the contribution from blocked nanoparticles. Indeed, the analysis of hyperthermia data using this model indicates that the contribution to heat generation spans from 34.7% of the nanoparticles for a field of 110 Oe up to 52.5% at 170 Oe.Item POVM no contexto de eletrodinâmica quântica de cavidades(Universidade Federal de Goiás, 2017-03-13) Assis, Rogério Jorge de; Almeida, Norton Gomes de; http://lattes.cnpq.br/3182841849332242; Almeida, Norton Gomes de; Villas-Boas, Celso Jorge; Almeida, Agnaldo Rosa deIn this work it is proposed a simplified scheme to unambiguously discriminate between one of two nonorthogonal cavity field states. This scheme, which is based on POVM - positive operator valued measure, uses one three-level atom as the ancilla to obtain information on the cavity field state, the target. The efficiency of this scheme in discriminating the two quantum states is analy zed by comparing the maximum theoretical success probability with the maximum success probability possible to our case.Item Troca de Emaranhamento e Teletransporte Controlado no contexto de rotações de Faraday fotônicas(Universidade Federal de Goiás, 2011-03-04) Bastos, Wellison Peixoto; Cardoso, Wesley Bueno; Baseia, Basilio; http://lattes.cnpq.br/5804506385505435; Baseia, Basilio; Cardoso, Wesley Bueno; Mizrahi, Salomon Sylvain; Fonseca, Tertius Lima daTaking advantage of the Faraday rotations that occur in a photonic cristal placed in an optical cavity with low quality factor, we proposed two schemes to obtain the swapping of entanglement of atomic states, useful in quantum communication and quantum computation. They employ three-level atoms in a -configuration, a linearly polarized photon source, a single detector, and a quarter wave plate. Three (four) cavities are used in the first (second) scheme. An additional scheme was also proposed to obtain controlled teleportation of superposition states, partial controlled teleportation of entangled states and controlled teleportation of entanglement. In all schemes we have included the imperfections that affect the system, such as transmission and coupling of photons in optical components, the fraction of photons with a desired polarization, the quantum efficiency of single photon detection, the effective solid angle where the photon are collected, and the rate of emitted photons by the source. Under these realistic conditions we estimate the success probability of each proccess, including the time spent for its realization.Item Investigação da influência da estrutura cristalina no efeito exchange bias espontâneo da série La1,5(Sr0,5-xBax)CoMnO6(Universidade Federal de Goiás, 2021-03-18) Belluzi, Marlon Boldrin; Bufaiçal, Leandro Felix de Sousa; http://lattes.cnpq.br/1392206843733548; Bufaiçal, Leandro Felix de Sousa; Ferreira, Letície Mendonça; Franco Júnior, AdolfoThe exchange bias (EB) effect is of great academic interest due to its potential applications in spintronics. Recently there were discovered some material exhibiting the EB effect spontaneously, i.e., even after being cooled in the absence of an external magnetic field. The main focus of this work is to investigate the influence of crystalline and electronic structures on the spontaneous EB effect. Therefore, here we describe the synthesis and structural, electronic and magnetic characterizations of polycrystalline samples of the La1.5(Sr0.5-xBax)CoMnO6 series. The main objective was to investigate the evolution of the magnetization of the system when Sr is gradually substituted by Ba. Polycrystalline samples were synthesized by conventional solid state reaction, and their structural properties were characterized by powder X-ray diffraction and the Rietveld Refinement. The magnetic properties were investigated by means of magnetization as a function of temperature [M(T)] and magnetization as a function of magnetic field [M(H)] measurements. The compounds were formed in a single phase, in the rhombohedral space group 𝑅3̅c. In addition, it was observed that the lattice parameters increase as the Ba concentration increases. The M(T) measurements indicate that all compounds have ferromagnetic (FM) and antiferromagnetic (AFM) ordering, where an increase in the proportion of the AFM phase was observed as the Ba concentration increases. Also, a trend of change is observed in the average spin state of the Co3+ ions, which varies from the low spin (LS) configuration to the high spin (HS) configuration as the Ba concentration increases. The M(H) measurements performed after cooling the samples in zero field showed a robust spontaneous EB effect, with the concentration x = 0.25 having the greatest effect ever observed. M(H) measurements taken after cooling the materials in the presence of an external field showed a qualitative behavior similar to those taken after cooling in zero field. The variations in the exchange bias effect observed throughout the series can be explained by the variations in the AFM phase and in the spin state of Co3+.Item Estudo das interações de moléculas orgânicas com imunoglobulinas G(Universidade Federal de Goiás, 2015-04-30) Bezerra, Fabio de Castro; Gonçalves, Pablo José; http://lattes.cnpq.br/0515343409614452; Gonçalves, Pablo José; Hioka, Noboru; Souza, Márcio Adriano Rodrigues(Sem resumo em outra língua)Item Relativistic symmetry in quantum information theory(Universidade Federal de Goiás, 2022-04-04) Bidinotto, Alexandre Borges; Taillebois, Emile Raymond Ferreira; Avelar, Ardiley Torres; http://lattes.cnpq.br/5732286631137637; Avelar, Ardiley Torres; Santana, Ademir Eugênio de; Cardoso, Wesley BuenoThis dissertation begins with a succinct introduction to group theory to enable the understanding of special relativity theory from a symmetrical point of view. From this perspective, the notion of hierarchy of dynamical variables, which is present in relativity, is introduced to quantum mechanical formalism in order to construct the irreducible unitary representations of the Poincaré group for secondary variables. Given this discussion, the questions regarding the existence of a subset of transformations in which the Wigner rotations associated do not depend on the momenta. In sequence, the relativistic Stern-Gerlach observable is presented. This observable also depends on the momenta, so the initial problem on the density matrices for spin remains unsolved. The open question on the Stern-Gerlach observable is what is the minimum number of measurements in order to fully determine a relativistic density matrix. Both questionings on this dissertation can lead to the determination of the quantum state tomography of relativistic particles, which is the further goal of this document.Item Thermodynamics and the Unruh effect(Universidade Federal de Goiás, 2020-04-13) Borges, Lucas Aurélio de Oliveira; Céleri, Lucas Chibebe; http://lattes.cnpq.br/6630683190018665; Céleri, Lucas Chibebe; Braghin, Fábio Luis; Vanzela, Daniel Augusto TurollaA uniformly accelerated detector perceives the Minkowski vacuum as a thermal state. In particular, for a massless scalar field, one cannot distinguish these two scenarios -accelerated detector in the vacuum and an inertial detector in contact with a thermal reservoir- just by using a point-like detector. In this work we show that one can probe the existence of acceleration by using an extended detector with dimension perpendicular to the acceleration direction. Also, we verify that the internal degrees of freedom of the detector may get entangled by a process of spontaneous emission, and as such is dependent on the initial state of the detector. It is found that the entropy production and entropy fluxes from out the detector also allow one to tell the two scenarios apart: more internal entangled detectors produce less entropy and vice-versa; the wavelength of the sought particle is the critical length at which the behavior of the two system is inverted.Item A possible inadequacy of a recent proposal for redefining heat and work in quantum thermodynamics(Universidade Federal de Goiás, 2021-03-15) Bottosso, Eduardo Borges; Almeida, Norton Gomes de; http://lattes.cnpq.br/3182841849332242; Moussa, Miled Hassan Youssef; Céleri, Lucas Chibebe; Almeida, Norton Gomes deA primeira identificação de um sistema quântico aberto como um modelo para um motor térmico quântico data de 1959. Desde então, a física não tem um conjunto concreto de fórmulas para definir, com precisão, como lidar com o calor e trabalhar no contexto de conjuntos quânticos . Uma das propostas mais proeminentes, que foi afirmada pelo artigo de R. Alicki de 1979, tem um regime de validade limitado e pode levar a algumas inconsistências com relação à primeira lei da termodinâmica. Várias abordagens para o problema foram propostas, levando a um novo conjunto de definições para calor e trabalho em termodinâmica quântica. Particularmente, novas redefinições para calor e trabalho foram introduzidas, as quais são baseadas na entropia de von Neumann. Nosso objetivo aqui é apresentar essa nova formulação, bem como sua motivação e investigar as consequências dessas fórmulas. Estudamos alguns modelos simples que empregam esse novo conjunto de definições. Nossa análise mostra um comportamento peculiar dos sistemas quânticos quando esse novo formalismo é dado como certo, possivelmente indicando uma inadequação dessas novas definições.Item Estudo de encapsulação de nanopartículas magnéticas em nanoporos de alumina.(Universidade Federal de Goiás, 2010-05-26) BRANQUINHO, Luis Cesar; BAKUZIS, Andris Figueiroa; http://lattes.cnpq.br/3477269475651042In this work we investigated the encapsulation of magnetite nanoparticles into the nanopores of anodic alumina membranes using atomic force microscopy (AFM), vibrating sample magnetometer (VSM) and electron magnetic resonance (EMR). Three biocompatible magnetic fluids, with different nanoparticle diameters, stably dispersed in water at physiological conditions, were used. The nanoparticles were obtained through the coprecipitation method and characterized by X-ray diffraction, from which we obtained the nanoparticle size and confirmed the crystal structure. The Scherrer´s relation revealed a nanoparticle diameter of 10.1nm, 12.3nm and 13.8nm. The alumina membrane were prepared through anodization process. The nanopores were arranged on a hexagonal lattice with an alumina thickness of 4 μm, a distance between pores (center to center) of 105 nm, and samples containing nanopores with diameter of 35 nm or 80 nm. The method of encapsulation of nanoparticles consisted of depositing a drop of magnetic fluid into the surface of alumina. The fluid enters the nanopores through capillarity carrying the nanoparticles into it. AFM images prove that we had success in encapsulating nanoparticles only for the alumina samples with nanopores with a size of 80 nm. Magnetization data of the alumina sample containing nanoparticles with a diameter of 13.8nm encapsulated into nanopores of 80 nm, revealed an increase, with respect to the first procedure of encapsulation, of 48 % of the nanoparticles internalized into the nanopore after the second process of encapsulation. Further, different from all the samples investigated, EMR data for the alumina containing nanopores of 80 nm and nanoparticles of 13.8 nm, after the first procedure of encapsulation, had shown perpendicular magnetization with respect to the alumina surface. The EMR spetra were curve fitted using two Gaussian lines, one representing the nanoparticles with magnetization parallel to the surface and the other perpendicular. AFM images suggest, in our sample, that residues on the alumina surface are responsible for the parallel component. The magnetic resonance field data, for the perpendicular contribution, were analyzed taking into account in the energy density terms with uniaxial and cubic symmetry. The uniaxial energy contribution had a term due to magnetic dipolar interaction, between nanoparticles forming a linear chain, a magnetostatic term, due to the nanostructures self-organization, and also a magnetoelastic contribution, which came from the stress generated by the packing of nanoparticles, whose origin were related to the dipolar interaction between nanoparticles forming the linear chain. Indeed, the theoretical analysis allowed us to conclude that the mean size of the chain could vary from 4 to 9.5 nanoparticles. Finally, after heating the alumina, at 300°C for one hour, which contained nanoparticles with a size of 10.1 nm, and dissolving it in NaOH aqueous solution, AFM data were obtained. The AFM images confirmed the existence of nanowires. The diameter distribution, obtained from the AFM images, were curve fitted with a lognormal distribution revealing a modal diameter for the nanowires of 25,8 0, ± 4nm and diameter dispersity of 0,30 ± 0,02nm .Item Dinâmica molecular e particionamento do marcador de spin di-terc-butil nitróxido em membranas de estrato córneo. Efeito de Terpenos(Universidade Federal de Goiás, 2009-03-31) CAMARGOS, Heverton Silva de; ALONSO, Antônio; http://lattes.cnpq.br/5013069863616789Terpenes are a very promising class of skin penetration enhancers especially due to their low potential of irritation in the skin. In this work, we have used the electron paramagnetic resonance (EPR) spectroscopy of the small spin label di-tert-butyl nitroxide (DTBN), which partitions the aqueous and hydrocarbon phases, to study the interaction of the terpenes ®-terpineol, 1,8-cineole, L(-)-carvone and (+)-limonene with the uppermost skin layer, the stratum corneum, and the membrane models of 1,2-dipalmitoyl-sn-glycero- 3-phosphatidylcholine (DPPC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). The EPR spectra indicated that the terpenes increase both the partition coe±cient and the rotational di®usion rate of the spin labels in the stratum corneum membranes whereas for DMPC and DPPC bilayers were observed similar e®ects only at temperatures below the liquid-crystalline phase. The EPR parameter associated to probe polarity inside the membranes showed thermotropic induced changes, suggesting relocations of spin probe, which were dependent of the membrane phases. While DMPC and DPPC bilayers showed abrupt changes in the partitioning and rotational correlation time parameters at the phase transitions, the SC membranes were characterized by slights changes in whole interval of measured temperatures, presenting the greatest changes or membranes reorganizations in the temperature range of v50 to v74±C. The results suggest that the terpenes act as spacers that weaken the hydrogen-bonded network at the polar interface thus °uidizing the stratum corneum lipids and, in consequence, increase the permeation of small polar molecules across the membranes. 2Item Propriedades estatísticas de fótons de micro-ondas gerados por uma junção túnel(Universidade Federal de Goiás, 2022-10-30) Campos, Maikon Bruno Alves; Mendes, Udson Cabral; https://lattes.cnpq.br/2549501479254454; Mendes, Udson Cabral; Almeida, Norton Gomes de; Silva, Cláudio José daIn this dissertation, we investigate the statistical properties of microwave photons generated by a tunnel junction coupled to a microwave resonator. For that, we developed the master equation formalism to calculate the statistical properties of (i) an electromagnetic field mode coupled to a thermal reservoir and (ii) to a squeezed vacuum reservoir. Furthermore, we derived the Hamiltonian of the tunnel junction coupled to a microwave resonator. This allows us to derive the master equation for the tunnel junction coupled to a microwave resonator and Confirm that (i) in the absence of ac voltage, the junction behaves as a thermal reservoir and (ii) in the presence of an ac voltage oscillating at a frequency equal to twice the frequency of the resonator, the junction behaves as a squeezed reservoir. Also we studied the tunnel junction coupled to a microwave resonator subjected to ac voltage with a frequency equal to three times the resonator frequency, theoretically demonstrating the possibility of generating photon trios, which has already been explored experimentally, but which has yet to be has no theoretical explanation for these experiments.