Now showing items 1-20 of 588

    • Propiedades magnéticas de agregados de metales 3d adsorbidos sobre superficies no magnéticas 

      Hernández Vázquez, Esther Elena (01/11/2019)
      The magnetic elements of the 3d row of the periodic table, have been extensively studied from an experimental and theoretical points of view. The study of these systems has been encouraged because their possible applications ...
    • Recuperación mejorada de petróleo con D-Limoneno diluido en salmuera 

      Gaitan-Espinosa, Mauricio (05/02/2020)
      D-Limonene, a compound consisting of terpenes in its dextrogyrous form, is used as a degreaser, hydrocarbon waste cleaner and as a sand oil separator. In this thesis, the use of this solvent is proposed as a chemical ...
    • Estudio experimental de nanotubos de carbono dopados con nitrógeno y de óxido de grafeno 

      Sánchez Salas, Roque (10/07/2017)
      "En esta tesis se presentan la segunda parte del estudio sistemático de síntesis y caracterización de nanotubos de carbono dopados con nitrógeno (CNx) mediante la técnica de deposición química de vapores (CVD). Partimos ...
    • "Métodos supersimétricos en la física de medios materiales" 

      de la Cruz Díaz, Josué Domingo (11/07/2019)
      "En los capítulos 2 y 3 se propone una generalización al método uniparamétrico (γ-deformado) de factorización estrictamente isoespectral a un caso biparamétrico incluyendo un desplazamiento ε en los operadores de factorización ...
    • Síntesis por solidificación rápida y caracterización magneto-estructural y magnetocalórica de la aleación cuaternaria Ni37.5Co12.5Mn35Ti15 

      López Cruz, Mauricio (13/07/2020)
      "En el presente trabajo de tesis se estudian las propiedades estructurales, microestructurales, térmicas y magnéticas de cintas recién solidificadas (referidas como as-cast) y tratadas térmicamente desde 973 K a 1173 K ...
    • Aristotle: the first encyclopedist 

      Rosu Barbus, Haret-Codratian (2002)
      "Aristotle was the first to declare himself in the class of natural philosophers (physiologoi) and he was the first physicist because he spelled out the first definitions of some basic physical concepts. Moreover, he was ...
    • On arithmetic detection of grey pulses with application to Hawking radiation 

      Rosu Barbus, Haret-Codratian; Planat, Michel (2002)
      "Micron-sized black holes do not necessarily have a constant horizon temperature distribution. The black hole remote-sensing problem means to find out the "surface" temperature distribution of a small black hole from the ...
    • KdV adiabatic index solitons in barotropic open FRW cosmologies 

      Rosu Barbus, Haret-Codratian (2002)
      "Applying standard mathematical methods, it is explicitly shown how the Riccati equation for the Hubble parameter H() of barotropic open FRW cosmologies is connected with a Korteweg-de Vries equation for adiabatic index ...
    • One-parameter Darboux-transformed quantum actions in thermodynamics 

      Rosu Barbus, Haret-Codratian; Aceves de la Cruz, Fermín (2002)
      "We use nonrelativistic supersymmetry, mainly Darboux transformations of the general (one-parameter) type, for the quantum oscillator thermodynamic actions. Interesting Darboux generalizations of the fundamental Planck and ...
    • Gravitational bouncing of a quantum ball: Room for Airy's function Bi 

      Rosu Barbus, Haret-Codratian (2002)
      "I apply (i) a classical version of the Ermakov-Lewis procedure and (ii) the strictly isospectral supersymmetric approach to the Schrodinger free fall of the bouncing ball type. In both cases, the Airy function Bi, which ...
    • Newton´s laws of motion in the form of a Riccati equation 

      Nowakowski, Marek; Rosu Barbus, Haret-Codratian (2002)
      "We discuss two applications of a Riccati equation to Newton´s laws of motion. The first one is the motion of a particle under the influence of a power law central potential V(r)=krε. For zero total energy we show that the ...
    • Ramanujan sums for signal processing of low-frequency noise 

      Planat, Michel; Rosu Barbus, Haret-Codratian; Perrine, Serge (2002)
      "An aperiodic (low-frequency) spectrum may originate from the error term in the mean value of an arithmetical function such as Mobius function or Mangoldt function, which are coding sequences for prime numbers. In the ...
    • Magnetic properties of fe1 / crn nanoinclusions in fe 

      Pedro Gilberto, Alvarado Leyva; Montejano Carrizales, Juan Martín; Morán López, José Luis (Sociedad Mexicana de Física, A. C., 2002)
      "The magnetic properties of Fe1/CrN inclusions in a Fe matrix are calculated as a function of the Cr number of atoms N at zero temperature, and for N ? 168. The electronic structure is determined by using a realistic ...
    • Words for nobel prizes 

      Rosu Barbus, Haret-Codratian (2003)
      "We present the statistics of the significant nouns and adjectives of social impact figuring in the nominations of the Nobel prizes in Physics and Chemistry over the period of the awards from 1901 to 2001."
    • Linear second-order differential equations for barotropic FRW cosmologies 

      Rosu Barbus, Haret-Codratian; Cornejo Pérez, Octavio (2003)
      "Simple linear second-order differential equations have been written down for FRW cosmologies with barotropic fluids by Faraoni. His results have been extended by Rosu, who employed techniques belonging to nonrelativistic ...
    • Transform of Riccati equation of constant coefficients through fractional procedure 

      Rosu Barbus, Haret-Codratian; Madueño, A. L.; García Díaz, José Socorro (2003)
      "We use a particular fractional generalization of the ordinary differential equations that we apply to the Riccati equation of constant coefficients. By this means the latter is transformed into a modified Riccati equation ...
    • Quantum Hamiltonians and prime numbers 

      Rosu Barbus, Haret-Codratian (2003)
      "A short review of Schrödinger Hamiltonian for which the spectral problem has beenVrelated in the literature to the distribution of the prime numbers is presented here. WeVnotice a possible connection between prime numbers ...
    • One-parameter nonrelativistic supersymmetry for microtubules 

      Rosu Barbus, Haret-Codratian; Cornejo Pérez, Octavio (2003)
      "The one-parameter nonrelativistic supersymmetry of Mielnik [J. Math. Phys. 25, 3387 (1984)] is applied to the simple supersymmetric model of Caticha [Phys. Rev. A 51, 4264 (1995)] in the form used by Rosu [Phys. Rev. E ...
    • Cyclotomy and Ramanujan sums in quantum phase locking 

      Planat, Michel; Rosu Barbus, Haret-Codratian (2003)
      "Phase-locking governs the phase noise in classical clocks through effects described in precise mathematical terms. We seek here a quantum counterpart of these effects by working in a finite Hilbert space. We use a coprimality ...
    • One-parameter isospectral special functions 

      Rosu Barbus, Haret-Codratian (2003)
      "Using a combination of the ladder operators of Pina [1] and the Pammetric operators of Mielnik [2] we introduce second order linear differential equations whose eigenfunctions are isospectral to the special functions of ...