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Now showing items 11-20 of 29
Estudo das transições de fase em cerâmicas ferroelétricas de PZT e PLZT através de espectroscopia mecânica
(Universidade Federal de São Carlos, 2008-10-08)
Lead titanate zirconate (PZT) and lanthanum-modified lead titanate zirconate (PLZT) ferroelectric ceramics have been great scientific and technologic interest, due to the possibility
of your physics properties can be ...
Regras de ocupação e influência de dopantes trivalentes em matrizes cerâmicas transparentes de PLZT 9/65/35
(Universidade Federal de São Carlos, 2009-10-01)
In this work, were investigated the occupancy of rare-earth ions in lattice site of the ferroelectric system (Pb,La)(Zr,Ti)O3, or PLZT. The influence on the structural, microestructural, dielectric, ferroelectric, optical ...
Propriedades estáticas e dinâmicas de portadores em heteroestruturas semicondutoras.
(Universidade Federal de São Carlos, 2002-10-30)
We have studied the dynamic and the stationary properties of carriers in semiconductor
heterostructures submitted to electric fields AC and DC and to magnetic fields
within the effective-mass approximation based on ...
Estudo de nanopartículas para preparação de compósitos com acoplamento magnetoelétrico
(Universidade Federal de São Carlos, 2009-09-03)
In recent years the necessity of new devices, in the electroelectronic industry, has lead to an increasing interest in materials called magnetoelectric (ME) or multiferroic (MF). Multiferroic is the term used to classify ...
Estudo sistemático das propriedades estruturais e magnéticas de amostras policristalinas do sistema PrxY1-xBa2Cu3O7-d
(Universidade Federal de São Carlos, 2008-08-10)
One of the most studied high TC superconductor is the YBa2Cu3O7 (Y-123) as well as the different substitutions on the Y site for different rare earth elements. Generally, this does not show important effects on the magnetic ...
Dielectric and elastic response of perovskites: modelling and simulation
(Universidade Federal de São Carlos, 2013-09-09)
Nesta tese é estudada a resposta elástica e elétrica das perovskitas. As perovskitas são amplamente utilizadas em aplicações técnicas, sendo fundamental na eletrônica e no campo relativamente novo da nanoeletrônica. Elas ...
Propriedades de transporte em óxidos condutores transparentes (TCOs): In2O3, SnO2 e SnO2:F
(Universidade Federal de São Carlos, 2014-03-14)
In this work we studied some of the structural features and transport in nanostructured metal oxides synthesized by the vapor -solid mechanism (VS) aiming their application in high performance devices. The structural ...
Estrutura de platô na magnetização em modelos de spins frustrados
(Universidade Federal de São Carlos, 2012-10-26)
This thesis study the phase transition, forms classical and quantum models of spin frustration. The Heisenberg model of spin 1/2 with exchange anisotropy with competitive interactions between first (J1) and second (J2) ...
Relaxação estrutural em ligas vítreas e parcialmente cristalizadas do sistema Cu-Zr-Al através da técnica de espectroscopia mecânica
(Universidade Federal de São Carlos, 2013-11-08)
In recent years the study of bulk metallic glasses (BMG) is being of great scientific and technological interest due to their unique properties (the lack of long range atomic order in the structure and compositional ...
Mecanismos de condução e relaxação elétrica em cerâmicas multiferróicas de Pb(Fe2/3W1/3)O3 e Pb(Fe1/2Nb1/2)O3
(Universidade Federal de São Carlos, 2013-12-19)
Multiferroic are materials which have at least two of the three ferroics orders: ferromagnetism, ferroelectricity and/or ferroelasticity. The coupling between these properties, make multiferroic materials of great technological ...