Magnetic Field Configurations
Mostrando 1-12 de 26 artigos, teses e dissertações.
-
1. Diluted magnetic nanostructures in the presence of applied external fields / Estudo de nano estruturas diluídas magnéticas na presença de campos externos aplicados
In the present work we studied properties of the spintronic transport of nanostructures formed by layers of diluted magnetic semiconductors (DMS) and conventional semiconductors with crossed fields applied. The electric field is in the growth direction and the magnetic field is perpendicular t o this one. We studied two configurations of nanostructures where
Publicado em: 2008
-
2. Modelo de regiões ativas em rádio freqüências / Model of active regions at radio frequencies
The goal of this work is to model in 3-D the solar atmosphere over active regions in order to reproduce the emission of these regions at radio frequencies. The model computes the radiative transfer equations for the thermal bremsstrahlung and gyro-resonance emission mechanisms. Because there are no measurements of magnetic fields intensities in the higher so
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 27/06/2007
-
3. Estado fundamental e excitações coletivas de condensados de Bose-Einstein espinoriais / Ground state and collective excitations od spinor Bose-Einstein condensates
In the framework of the Bogoliubov theory, we determined the equilibrium configurations and the collective excitations of a homogeneous Bose-Einstein S = 1 spinor condensate, in the presence and absence of an externa1 magnetic field. In this thesis we found the equilibrium configurations as function of the parameters and m, where q is the intensity of the qu
Publicado em: 2007
-
4. Propriedades de equilÃbrio e de transporte da matÃria de vÃrtices em nanoestruturas supercondutoras
In the present thesis, we study theoretically the equilibrium properties and dynamics of the vortex matter in two classes of nanostructured superconductors: (i) mesoscopic samples, with dimensions comparable with the penetration depth; and (ii) films with periodic array of artificial traps. In both cases, the vortex lattice symmetry is strongly dependent on
Publicado em: 2007
-
5. Model of active regions at radio frequencies / Modelo de regiões ativas em rádio freqüências
Este trabalho tem como objetivo modelar em 3 dimensões a atmosfera solar acima de regiões ativas a fim de reproduzir a emissao destas em rádio freqüências. O modelo calcula as equações de transferência radiativa para os mecanismos de emissão bremsstrahlung e giro-ressonância térmicos. Por não existirem medidas das intensidades dos campos magnéti
Publicado em: 2007
-
6. Optimization of saddle coils for magnetic resonance imaging
In Nuclear Magnetic Resonance (NMR) experiments, besides the apparatus designed to acquire the NMR signal, it is necessary to generate a radio frequency electromagnetic field using a device capable to transduce electromagnetic power into a transverse magnetic field. We must generate this transverse homogeneous magnetic field inside the region of interest wit
Brazilian Journal of Physics. Publicado em: 2006-03
-
7. ConfiguraÃÃo, anisotropia e defeitos em uma rede de vÃrtices na presenÃa de nanoarmadilhas
Since Abrikosov s work in 1957, it. has been clear the vortex lattice existence and stability in specific magnetic fields and temperature values of type ll super- conductors. On external currents and Thermic fluctuations, vortices move through the superconductor salable resulting thermal dissipation. But it is salvage to most. actual technologic applications
Publicado em: 2006
-
8. MAGNETOIMPEDÂNCIA COMO FERRAMENTA PARA A CARACTERIZAÇÃO MAGNÉTICA DE MICROFIOS AMORFOS / MAGNETOIMPEDANCE AS A TOOL TO INVESTIGATE THE MAGNETIC PROPERTIES OF MICROWIRES
The possibility of exploring the magnetic properties of amorphous microwires in technological applications has attracted the attention of the scientific community in the last years. Beyond, the magnetoimpedance effect has been established as a powerful tool to study these properties. In this work we show a study of the magnetic properties of Joule heated gla
Publicado em: 2006
-
9. Simulação MHD Bi-Dimensional da interação do vento solar com magnetosferas planetárias / Two-dimensional MHD simulation of the solar wind and planetary magnetospheres interaction
Space weather refers to conditions on the Sun and solar wind, magnetosphere and ionosphere that can influence the performance and reliability of ground-based technological systems and can aect the human life and health. The study of magnetospheres is of great scientific interest because it provides ideal laboratories to study the behavior of plasmas. The siz
Publicado em: 2006
-
10. EFEITOS CORROSIVOS ENCONTRADOS EM MATERIAIS MAGNÉTICOS EMPREGADOS EM ORTODONTIA
The employment of magnetic alloys have allowed the criation of new options on odontological therapies, specially in orthodontics, where its utilization is already quite outspread. The innovation with the use of magnets came with the introduction of new magnetic alloys based on elements rare earth that belong to the lanthanum family as well as the samarium-co
Publicado em: 2006
-
11. Ignitor: physics and progress towards ignition
Thermonuclear ignition condition for deuterium-tritium plasmas can be achieved in compact, high magnetic field devices such as Ignitor. The main scientific goals, the underlying physics basis, and the most relevant engineering solutions of this experiment are described. Burning plasma conditions can be reached either with ohmic heating only or with small amo
Brazilian Journal of Physics. Publicado em: 2004-12
-
12. Theoretical analysis of formation and sustainment methods for compact toroids
Recent theoretical studies on the use of neutral beams (NB), rotating magnetic fields (RMF) and helicity injection (HI) to form and sustain compact toroids are reported. A Monte Carlo code was employed to study NB injection in Field Reversed Configurations (FRC) and Spheromaks. The code calculates the ionization of the neutral particles and follows the exact
Brazilian Journal of Physics. Publicado em: 2004-12