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Influence of synthesis conditions on carbonate entrapment in perovskite SrSnO(3)
(Elsevier B.V., 2009-01-15)
Strontium stannate (SrSnO(3) a perovskite material, was synthesized by the polymeric precursor method, with different routes to eliminate organic matter. The utilization of pure oxygen for the elimination of organic matter ...
Mechanochemical synthesis of ceramic powders with perovskite structure
(Elsevier B.V., 2003-12-20)
The mechanical activation is one of the most effective method for obtaining highly disperse system due to mechanical action stress fields form in solids during milling procedure. This effect results in changes of free ...
Nature of potential barrier in (Ca-1/4,Cu-3/4)TiO3 polycrystalline perovskite
(Elsevier B.V., 2006-01-01)
The nonohmic electrical features of (Ca-1/4,Cu-3/4)TiO3 perovskite ceramics, which have very strong gigantic dielectric is believed originate from potential barriers at the grain boundaries. In the present study, we used ...
Nanoparticle synthesis of La1-xSrxMnO3 (0.1, 0.2 and 0.3) perovskites
(Institute of Electrical and Electronics Engineers (IEEE), 2002-09-01)
Synthesis of La1-xSrxMnO3 (x = 0.1, 0.2 and 0.3) by homogenous coprecipitation method using urea as precipitant agent Is reported. The particles are smaller than 200 nm after heating at 950 degreesC. Temperature dependence ...
Lanthanum cobaltite black pigments with perovskite structure
(2013-05-09)
In this work La1-xCaxCoO3 (x = 0-0.4) pigments were synthesized by the polymeric precursor method with heat treatments at 700, 800 and 900 C for 4 h. The powders were characterized by colorimetry, UV-vis spectroscopy and ...
Quantum chemical modeling of perovskite: An investigation of piezoelectricity in ferrite of yttrium
(Springer, 2011-07-01)
In a previous article, we used Hartree-Fock (HF) theory to study the piezoelectricity in BaTiO(3). In this paper, we applied the Douglas-Kroll-Hess second order scalar relativistic method to investigate the possible ...
Designing Gaussian basis sets to the theoretical study of the piezoelectric effect of perovskite (BaTiO3)
(Elsevier B.V., 2004-02-23)
Gaussian basis sets (24s14p, 30s19p14d, and 33s21p14d for O (P-3), Ti (S-5), and Ba (S-1) atoms, respectively), are designed with the strategy of the Generator Coordinate Hartree-Fock method. The basis sets are then ...
Seeding of PMN powders made by the Pechini method
(Elsevier B.V., 2001-01-01)
The partial oxalate method, with the columbite route, associated with the Pechini method, was used to obtain a very fine ceramic powder at low temperature. Using this route it was possible to obtain a very reactive powder ...
Phase analysis of seeded and doped PbMg1/3Nb2/3O3 prepared by organic solution of citrates
(1996-07-01)
PbMg1/3Nb2/3O3 (PMN) prepared by organic solution of citrates was analyzed by the Rietveld method to determine the influence of seeds and dopants on the perovskite and pyrochlore phase formation. It was observed that ...
Lanthanum-based perovskites obtained by the polymeric precursor method
(Springer, 2008-01-01)
Cobalt oxides, specially the ones with perovskite structure, are of a high technological interest, due to their interesting optical, electrical and magnetic properties. La(1 -x)Ca(x)CoO(3) powder samples were synthesized ...