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Influence of Tungsten Dopant on Sintering and Curie Temperatures of Ba(Zr0.10Ti0.90)O-3 Ceramics
(Taylor & Francis Ltd, 2008-01-01)
Ba(Zr0.10Ti0.90)O3 (BZT10) and W+ 6 substituted BZT ceramics (BZT10:W) were prepared by mixed oxide method. The effect of W+ 6 addition in the BZT was evaluated by X-ray diffraction (XRD), dilatometer analysis, microstructural ...
Effect of powder milling and dopant addition on the current-voltage characteristics of SnO2-based ceramics
(2001-01-01)
Non-linear electrical properties of SnO2-based ceramics were investigated as a function of powder agglomeration condition and as a function of dopant addition. All doped powders presented a single phase, cassiterite, as ...
Effect of atmosphere and dopants on sintering of SnO2
(2002-12-01)
Tin oxide is an n type semiconductor material with a high covalent behavior. Mass transport in this oxide depends on the surface state promoted by atmosphere or by the solid solution of aliovalent oxide doping. The sintering ...
Influence of the common varistor dopants (CoO, Cr2O3 and Nb2O5) on the structural properties of SnO2 ceramics
(Elsevier B.V., 2004-07-01)
The influence of dopants commonly used in SnO2 varistor ceramics, such as CoO, Cr2O3 or Nb2O5, on the structural properties of SnO2 was investigated. Several SnO2-based ceramics containing only one of the dopants were ...
Efeito da adição de dopantes durante a síntese do precursor columbita para a preparação da cerâmica ferroelétrica relaxora PMN
(Associação Brasileira de Cerâmica, 1999-12-01)
O Niobato de Chumbo e Magnésio (PMN) é um material que possui propriedades ferroelétricas de relaxação. Essa propriedade pode ser acentuada ou alterada mediante a adição de dopantes. Neste trabalho foi demonstrado como a ...
Effect of atmosphere and dopants on sintering of SnO2
(1998-12-01)
Tin oxide is an n-type semiconductor material with a high covalent behavior. Mass transport in this oxide depends on the surface state promoted by atmosphere or by the solid solution of a non-isovalent oxide doping The ...
Effect of cobalt(II) oxide and manganese(IV) oxide on sintering of tin(IV) oxide
(1996-03-01)
Additions of 0.5 to 2.0 mol% of CoO or MnO2 onto SnO, promote densification of this oxide up to 99% of theoretical density. The temperature of the maximum shrinkage rate (TM) and the relative density in the maximum ...
Spectroscopic studies of SnO2 doped with Cr, Co or Nb
(2003-03-15)
SnO2 ceramics doped with different amounts of Co, Cr or Nb were investigated using visible and infrared spectroscopy at room temperature. Based on the observed d-d transitions the valence states of incorporated dopants ...
Nonlinear characteristics of Cr2O3, WO3, ZnO and CoO doped SnO2 varistors
(Elsevier B.V., 2006-01-01)
SnO2 based ceramics doped with 1.0 mol% ZnO, 1.0 mol% CoO, 0.1 mol% WO3 and 0.05 mol% Cr2O3 show varistor behavior with nonlinear coefficient alpha = 33, breakdown electric field E-B = 12.5 kV/cm, leakage current I = 0.63 ...
Room-temperature photoluminescence in amorphous SrTiO3-The influence of acceptor-type dopants
(2002-11-01)
Room-temperature photoluminescence (PL) was observed in undoped and 2 mol% Cr-, Al- and Y-doped amorphous SrTiO3 thin films. Doping increased the PL, and in the case of Cr significantly reduced the associated PL wavelength. ...