Oscillator
Mostrando 1-12 de 289 artigos, teses e dissertações.
-
1. RING CURRENT IN ANTHRACENE AND PHENANTHRENE: CORRECTION TO HÜCKEL PARAMETERS
Excessive degeneracy in the ground state of the π-electron energy levels of anthracene was removed using the Hückel method by correcting the Coulomb integral of the four central carbon atoms. A further correction to the resonance integral was proposed based on the ring-current model, which describes the π-ring current flow along the molecule’s perimeter
Química Nova. Publicado em: 2022
-
2. Proposta de uma Abordagem Iterativa Analítica para o Oscilador Harmônico Simples
Resumo Neste trabalho propusemos uma abordagem iterativa analítica em que a evolução temporal foi substituída pelo número de iterações. E para o caso de um sistema massa-mola obtivemos sua velocidade e sua posição em função do tempo como somas parciais de séries que convergiram para as funções trigonométricas que são as soluções do oscilado
Rev. Bras. Ensino Fís.. Publicado em: 28/10/2019
-
3. O oscilador linearmente amortecido revisitado
Resumo O oscilador harmônico amortecido por atrito de contato superficial é revisitado com uma descrição física e matemática mais robustas e abrangentes. Várias propriedades do sistema são apresentadas e discutidas, como a solução para o caso geral de condições iniciais, envoltórias do movimento, número exato de oscilações, dissipação insta
Rev. Bras. Ensino Fís.. Publicado em: 28/10/2019
-
4. Equivalence between the Dirac oscillator and a spin-1/2 fermion embedded in a transverse homogeneous magnetic field: movement in a (2 + 1)-dimensional world
Abstract It is shown that the Dirac oscillator in a (2+1)-dimensional spacetime can be interpreted as a spin-1/2 fermion embedded in a transverse homogeneous magnetic field.
Rev. Bras. Ensino Fís.. Publicado em: 07/10/2019
-
5. A origem clássica da força do oscilador
Resumo O conceito de força do oscilador é útil em várias áreas da química e da física, tais como emissão e absorção de radiação, constante dielétrica, índice de refração e colisões inelásticas entre partículas carregadas e átomos e moléculas. Na maioria dos livros didáticos, o conceito de força de oscilador é introduzido de forma ad h
Rev. Bras. Ensino Fís.. Publicado em: 07/10/2019
-
6. Equivalence between the planar Dirac oscillator and a spin-1/2 fermion embedded in a transverse homogeneous magnetic field
Abstract It is shown that a spin-1/2 fermion coupled to the axially symmetric electromagnetic vector potential has the same matrix structure as that one for the planar Dirac oscillator. In particular, the planar Dirac oscillator can be interpreted as a charged particle minimally coupled to a transverse homogeneous magnetic field.
Rev. Bras. Ensino Fís.. Publicado em: 10/07/2019
-
7. Two helpful developments towards better understanding of adiabatic invariance in classical mechanics
Abstract The topic of difficult understanding of adiabatic invariance in classical mechanics is dealt with in a more understandable way. Using the one-dimensional harmonic oscillator as an example, the goals of this paper are twofold. First, given a first-order parameter variation, the second-order magnitude of the correction to the adiabatic invariant is es
Rev. Bras. Ensino Fís.. Publicado em: 21/09/2018
-
8. Transition from Thermokinetic to Chemical Instabilities in a Modified Sal’nikov Model
Traditionally, thermokinetic and chemical oscillations have been studied independently, but in cellular media recent studies have shown that cell’s temperature is not uniform. Thus, on this context it is possible to inquire about the influence of thermal effects on chemical oscillatory behavior and vice versa. To this end, in this paper we propose a dynami
J. Braz. Chem. Soc.. Publicado em: 2018-07
-
9. Annealing and Extended Etching Improve a Torsional Resonator for Thin Film Internal Friction Measurements
We evaluate two methods to improve the background internal friction of the Double Paddle Oscillator (DPO), which has a nominal low temperature value of Q-1 ≈ 2×10-8. We find that annealing the DPO in vacuum at 300°C for 3 hours systematically reduced Q-1 at all temperatures and revealed a 100K internal friction peak by permanently removing it. We also fi
Mat. Res.. Publicado em: 18/06/2018
-
10. The Equivalent Linearization Method with a Weighted Averaging for Analyzing of Nonlinear Vibrating Systems
Abstract In this paper, the Equivalent Linearization Method (ELM) with a weighted averaging, which is proposed by Anh (Anh, 2015), is applied to analyze some vibrating systems with nonlinearities. The strongly nonlinear Duffing oscillator with third, fifth, and seventh powers of the amplitude, the other strongly nonlinear oscillators and the cubic Duffing wi
Lat. Am. j. solids struct.. Publicado em: 2017-09
-
11. SOBRE UM ESTUDO DA ENTROPIA DE SHANNON NO CONTEXTO DA MECÂNICA QUÂNTICA: UMA APLICAÇÃO AO OSCILADOR HARMÔNICO LIVRE E CONFINADO
The aim of this study was a didactic presentation of the Shannon entropy in the quantum theory context, followed by application to the case of a one-dimensional harmonic oscillator in its ground state, both in the free case and confined case. The study of these systems allows us to highlight notions such as location or delocation of a particle, a possible in
Quím. Nova. Publicado em: 2016-07
-
12. Application of Higher Order Hamiltonian Approach to the Nonlinear Vibration of Micro Electro Mechanical Systems
Abstract This paper implements the higher order Hamiltonian method to analyze an electrostatically actuated nonlinear micro beam-based micro electro mechanical oscillator. First, second and third approximate solutions are obtained, and the frequency responses of the system are compared with energy balance method solution and previously solved Variational App
Lat. Am. j. solids struct.. Publicado em: 2016-03