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Nomenclatura Unesco > (22) Física

Mostrando recursos 181 - 200 de 70,739

181. Las calizas microcristalinas como material de construcción: el caso del Gris Pulpis - García del Cura, M. Ángeles; Benavente, David; Bernabéu, A.; Fort González, Rafael; La Iglesia, A.; Ordóñez, S.
[ES] En este trabajo se analizan las propiedades físicas y la durabilidad de una caliza microcristalina.El Gris Pulpis es una caliza microcristalina del Jurásico de la Cordillera Ibérica (Maestrazgo), cuyas características mineralógicas, petrográficas, cromáticas y alterabilidad se determinan detalladamente. Su aptitud para el pulido hace que sea un mármol comercial. Se establece la influencia de sus características estructurales (estilolitos, vénulas...) en sus propiedades físicas. Su resistencia a flexión supera los valores que cabría esperar en función de la estructura de esta roca que, a veces, presenta abundantes estilolitos y vénulas. Esto es debido a las características estructurales y mineralógicas de...

182. Estudio del efecto de los acabados superficiales en granitos y calizas para su aplicación en pavimentos exteriores de baldosas de piedra - García del Cura, M. Ángeles; Benavente, David; Bernabéu, A.; Martínez-Martínez, J.
Se han estudiado, para su utilización como baldosas de pavimentos, granito (Blanco Rafaela o Granito de Zarzalejo) y caliza microcristalina (mármol comercial Gris Pulpis) con diferentes acabados. Estos acabados son: pulido, apomazado, abujardado y flameado en ambas rocas y además acabado al ácido y amolado en la caliza. Se han determinado mediante ensayos estandarizados las tres propiedades físicas de mayor interés para el uso de la piedra natural como baldosa en pavimentos de exteriores: resistencia a la flexión bajo carga concentrada, a la abrasión y al deslizamiento. Se han realizado ensayos de durabilidad por ciclos de hielo-deshielo con posterior evaluación mediante...

183. Interacción entre los radio-jets y el material interestelar en radiogalaxias - Reynaldi, María Victoria
En este trabajo se estudian los sistemas nebulares (gas ionizado) localizados en las regiones más externas de potentes radiogalaxias y conocidos como Regiones Extendidas con Emisión de Líneas (EELR). Fueron descubiertos en forma sistemática mediante observaciones con el Telescopio Espacial Hubble (HST). Las propiedades que las definen desde su propio nombre son las grandes distancias hasta las cuales es posible localizarlas, superando el alcance de la componente estelar en las mismas imágenes del HST, y el tipo de líneas de emisión que componen su espectro. El estudio consta de la determinación del proceso de ionización dominante en la zona, mediante la...

184. Escola de Educação Física - Relação de alunos formados na ESEF de 1959 a 1963 - sem registro
Relação de alunos(as) formados(as) na Escola de Educação Física de 1959 a 1963, nos cursos: Superior em Educação Física, Educação Física Infantil, Medicina Aplicada à Educação Física e aos Desportos.

185. Escola de Educação Física - Relação de alunos que fizeram o Curso de Técnica Desportiva na ESEF de 1941 a 1968 - sem registro
Relação de alunos que fizeram o Curso de Técnica Desportiva na ESEF entre 1941 e 1968. O levantamento foi feito em 1974. A assinatura do documento é ilegível. Na frente do nome de cada aluno(a) há a indicação de uma ou duas modalidades esportivas, provavelmente indicando a especialidade de cada um(a).

186. Lenea Gaelzer, Certificado de participação ao Seminário de Dirigentes da Atividade Física Curricular - Escola Superior de Educação Física, ESEF
Certificado à Lenea Gaelzer, pela participação no Seminário da Atividade Física Curricular, patrocinado pela Secretaria de Educação Física e Desportos do Ministério da Educação e Cultura e realizado pela Escola Superior de Educação Física da Universidade Federal do Rio Grande do Sul, ocorrido nos dias 14,15 e 16 de Setembro de 1981.

187. «Viejismo » y prácticas profesionales : cuáles son las consecuencias para la persona mayor con discapacidad intelectual? - Clesse, Audrey; Missotten, Pierre; Richard, Ulrich
En Europa, tenemos una imagen negativa del envejecimiento : la edad (mayor de 55 anos) aparece como el factor de discriminación más importante, antes del sexo, origen étnico o religión (Eurobarometro, 2012). « Viejismo » – el hecho de transmitir estereotipos negativos relacionados con la edad mayor – influye de forma negativa la salud mental y física de la persona discriminada (Levy, 2003; Levy et al., 2009), pero también sus interacciones con los demás (Williams et al., 2003; 2009). Hoy en día, una persona con el síndrome de Down vive en promedio hasta los 55 años, mientras vivía hasta los...

188. Altius, citius, fortius...ditius? lógicas e estratégias do Comitê Oliímpico Internacional, comitê de candidatura e governo brasileiro na candidatura e escolha dos jogos olímpicos e paralímpicos Rio 2016 - Almeida, Bárbara Schausteck de
Orientador : Prof. Dr. Wanderley Marchi Júnior

189. Hawking radiation as perceived by different observers: an analytic expression for the effective-temperature function - Barbado, L. C.; Barceló, Carlos; Garay Elizondo, Luis Javier
Given a field vacuum state in a black hole spacetime, this state can be analysed in terms of how it is perceived (in terms of particle content) by different observers. This can be done by means of the effective-temperature function introduced by Barcelo et al (2011 Phys. Rev. D 83 041501). In Barbado et al (2011 Class. Quantum Grav. 28 125021), this function was analysed in a case-by-case basis for a number of interesting situations. In this work, we find a general analytic expression for the effective-temperature function which, apart from the vacuum state choice, depends on the position, the...

190. Electromagnetic effects in the pion dispersion relation at finite temperature - Gómez Nicola, Ángel; Torres Andrés, R.
We investigate the charged-neutral difference in the pion self-energy at finite temperature T. Within chiral perturbation theory (ChPT) we extend a previous analysis performed in the chiral and soft pion limits. Our analysis with physical pion masses leads to additional non-negligible contributions for temperatures typical of a meson gas, including a momentum-dependent function for the self-energy. In addition, a nonzero imaginary part arises to leading order, which we define consistently in the Coulomb gauge and comes from an infrared enhanced contribution due to thermal bath photons. For distributions typical of a heavy-ion meson gas, the charged and neutral pion masses...

191. Unimodular gravity and general relativity from graviton self-interactions - Barceló, Carlos; Carballo Rubio, Raúl; Garay Elizondo, Luis Javier
It is commonly accepted that general relativity is the only solution to the consistency problem that appears when trying to build a theory of interacting gravitons (massless spin-2 particles). Padmanabhan’s 2008 thought-provoking analysis raised some concerns that are having resonance in the community. In this paper we present the self-coupling problem in detail and explicitly solve the infinite-iterations scheme associated with it for the simplest theory of a graviton field, which corresponds to an irreducible spin-2 representation of the Poincaré group. We make explicit the nonuniqueness problem by finding an entire family of solutions to the self-coupling problem. Then we show...

192. Generation of uniform synthetic magnetic fields by split driving of an optical lattice - Creffield, Charles; Sols Lucía, Fernando
We describe a method to generate a synthetic gauge potential for ultracold atoms held in an optical lattice. Our approach uses a time-periodic driving potential based on quickly alternating two Hamiltonians to engineer the appropriate Aharonov-Bohm phases, and permits the simulation of a uniform tunable magnetic field. We explicitly demonstrate that our split-driving scheme reproduces the behavior of a charged quantum particle in a magnetic field over the complete range of field strengths, and obtain the Hofstadter butterfly band structure for the Floquet quasienergies.

193. Stress and field contactless sensor based on the scattering of electromagnetic waves by a single ferromagnetic microwire - Herrero Gómez, Carlos; Aragón Sánchez, Ana María; Hernando Rydings, Manuel; Marín Palacios, María Pilar
In this paper, we report an experimental study on the microwave modulated scattering intensity for a single Fe_2.25Co_72.75Si_10B_15 amorphous metallic microwire. The modulation is driven by applying a bias magnetic field that tunes the magnetic permeability of the ferromagnetic microwire. Furthermore, by using a magnetostrictive microwire, we also demonstrate that the microwave scattering is sensitive to mechanical stresses. In fact, we present a wireless microwave controlled stress sensor, suitable for biological applications, as a possible use of this effect. In addition, a first order theoretical approximation accounts for the observed influence of the magnetic permeability on the scattering coefficients. That...

194. Hybrid classical-quantum formulations ask for hybrid notions - Barceló, Carlos; Carballo- Rubio, Raúl; Garay Elizondo, Luis Javier; Gómez Escalante, Ricardo
We reappraise some of the hybrid classical-quantum models proposed in the literature with the goal of retrieving some of their common characteristics. In particular, first, we analyze in detail the Peres-Terno argument regarding the inconsistency of hybrid quantizations of the Sudarshan type. We show that to accept such hybrid formalism entails the necessity of dealing with additional degrees of freedom beyond those in the straight complete quantization of the system. Second, we recover a similar enlargement of degrees of freedom in the so-called statistical hybrid models. Finally, we use Wigner's quantization of a simple model to illustrate how in hybrid...

195. The fate of non-trivial entanglement under a gravitational collapse - Martín Martínez, Eduardo; Garay Elizondo, Luis Javier; León, Juan
We analyse the evolution of the entanglement of a non-trivial initial quantum field state (which, for simplicity, has been taken to be a bipartite state made out of vacuum and the first excited state) when it undergoes a gravitational collapse. We carry out this analysis by generalizing the tools developed to study entanglement behaviour in stationary scenarios and making them suitable to deal with dynamical spacetimes. We also discuss what kind of problems can be tackled using the formalism spelled out here, as well as single out future avenues of research.

196. Depth of maximum of air-shower profiles at the Pierre Auger Observatory. II. Composition implications - Aranda, V. M.; Arqueros Martínez, Fernando; García Pinto, Diego; Minaya Flores, Ignacio Andrés; Rosado, J.; Vázquez Peñas, José Ramón
Using the data taken at the Pierre Auger Observatory between December 2004 and December 2012, we have examined the implications of the distributions of depths of atmospheric shower maximum (X-max), using a hybrid technique, for composition and hadronic interaction models. We do this by fitting the distributions with predictions from a variety of hadronic interaction models for variations in the composition of the primary cosmic rays and examining the quality of the fit. Regardless of what interaction model is assumed, we find that our data are not well described by a mix of protons and iron nuclei over most of...

197. Depth of maximum of air-shower profiles at the Pierre Auger Observatory. I. Measurements at energies above 10(17.8) eV - Aranda, V. M.; Arqueros Martínez, Fernando; García Pinto, Diego; Minaya Flores, Ignacio Andrés; Rosado, J.; Vázquez Peñas, José Ramón
We report a study of the distributions of the depth of maximum, X-max, of extensive air-shower profiles with energies above 10(17.8) eV as observed with the fluorescence telescopes of the Pierre Auger Observatory. The analysis method for selecting a data sample with minimal sampling bias is described in detail as well as the experimental cross-checks and systematic uncertainties. Furthermore, we discuss the detector acceptance and the resolution of the X-max measurement and provide parametrizations thereof as a function of energy. The energy dependence of the mean and standard deviation of the X-max distributions are compared to air-shower simulations for different...

198. Cross sections for positron and electron collisions with an analog of the purine nucleobases: Indole - Chiari, Luca; Zecca, Antonio; Blanco Ramos, Francisco; García, Gustavo; Brunger, M.J.
Quantitative information about positron and electron collisions with nucleobases is required in charged-particle track simulations to accurately model and assess any radiation damage at the subcellular level in biological systems. However, scattering experiments have so far been restricted to the pyrimidine nucleobases. In this paper we report on total-cross-section measurements for positron impact on indole, a parent molecule of the purine nucleobases, at impact energies between 1 and 25 eV. We also present theoretical cross sections for elastic and total scattering, positronium formation, electronic excitations, and direct ionization between 1 and 500 eV, as calculated with the independent-atom model with...

199. Avaliação do ambiente escolar para o ensino e prática da educação física no ensino fundamental - Teixeira, Raíssa Ferreira
Dissertação (mestrado)—Universidade de Brasília, Centro de Estudos Avançados Multidisciplinares, 2015.

200. Atitudes de futuros Profissionais de Saúde e Serviço Social face ao trabalho com a populaçao idosa - Oliveira António Bettencorut da Camara, Stella Margarida de
Este estudio forma parte de una investigación aplicada a una muestra de 620 estudiantes de enseñanza superior del área de la salud (medicina, enfermería, fisioterapia) y del área social (Servicio Social y Política Social), de todos los cursos realizados en esa disciplina en Lisboa. El objetivo principal fue determinar las actitudes de los estudiantes de acuerdo a la posibilidad de un futuro trabajo con personas mayores. Usando el Modelo de Clases Latentes y el Criterio de Información de Bayes fue posible definir y caracterizar una Clase 1 (71%) de estudiantes que no desearían trabajar con personas mayores y una Clase...

 

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