Zobrazeno 1 - 10
of 351
pro vyhledávání: '"J. Ravez"'
Publikováno v:
physica status solidi (a). 184:459-464
Crystallographic and low frequency dielectric studies were performed on lead-tree non-stoichiometric perovskite ceramics of Ba 1-x Bi 2x/3 □ x/3 TiO 3 (0 ≤ x ≤ 0.15) composition. A classical ferroelectric behaviour was shown for x lower than 0.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::51f2addca1602668a758aa2099a40cca
https://doi.org/10.1002/1521-396x(200104)184:2<459::aid-pssa459>3.0.co
https://doi.org/10.1002/1521-396x(200104)184:2<459::aid-pssa459>3.0.co
Autor:
Catherine Elissalde, J. Ravez
Publikováno v:
Journal of Materials Chemistry. 11:1957-1967
Dielectric relaxations in ferroelectric ceramics occur at various frequencies, depending on the type of chemical or physical defects. These defects depend on either intrinsic or extrinsic heterogeneities due to special heat treatments (quenching, ann
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::afd2a0e3f9c79f4ac2775b81387306e0
https://doi.org/10.1039/b010117f
https://doi.org/10.1039/b010117f
Publikováno v:
The European Physical Journal Applied Physics. 11:9-13
A large number of lead-free BaTiO 3 -based ceramics were prepared. Depending on the composition, some of them exhibit a relaxor behaviour whose characteristics were related to the type of ionic substitution and to the substitution rate. The relaxor e
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::01cc44a2fe01eca742b785c07d6ae40c
https://doi.org/10.1051/epjap:2000140
https://doi.org/10.1051/epjap:2000140
Publikováno v:
Journal of Fluorine Chemistry. 103:35-40
Resume Study of the Sr 5 Ga 3 F 19 _ Sr 2 ZnGaF 9 system shows two solid solutions derived from the two limit phases. The first close to Sr 5 Ga 3 F 19 is disordered with Zn 2+ and Ga 3+ statistically in the octahedral sites; it shows a ferroelectric
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cb22dcf7168c198076257fc8dcd12dfe
https://doi.org/10.1016/s0022-1139(99)00256-0
https://doi.org/10.1016/s0022-1139(99)00256-0
Publikováno v:
Solid State Communications. 113:77-82
The BaTi0.65Zr0.35O3 and Ba0.92Ca0.08Ti0.75Zr0.25O3 compositions of the BaTiO3–BaZrO3–CaTiO3 system have been studied by X-ray diffraction on unpoled and poled ceramics. The dielectric peak of BaTi0.65Zr0.35O3 at T m =200 K (1 kHz), characteristi
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::fac2258f477c381b1efbbd639a524785
https://doi.org/10.1016/s0038-1098(99)00445-7
https://doi.org/10.1016/s0038-1098(99)00445-7
Publikováno v:
Phase Transitions. 66:109-118
X-ray diffraction studies versus temperature of Pb5Al3F19 powders have shown the grain size to have a great influence on the phase transition sequence. As in a single crystal, a coarse-grained powder (φgr > 5 μm) exhibits three phase transitions be
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::4e659b007e2744c4d4fe1aab7de4f6c6
https://doi.org/10.1080/01411599808222121
https://doi.org/10.1080/01411599808222121
Publikováno v:
Materials Letters. 36:81-84
Ceramics sintered at temperatures in the range 1200–1400°C and with composition Ba 1− x K x (Ti 1− x Nb x )O 3 (0.04≤ x ≤0.20) show a relaxor ferroelectric behaviour. All the corresponding dielectric characteristics, i.e., diffusivity of t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::9f336f369a0ad7327241f535ab552ad6
https://doi.org/10.1016/s0167-577x(98)00008-1
https://doi.org/10.1016/s0167-577x(98)00008-1
Autor:
P. Dubernet, J. Ravez
Publikováno v:
Ferroelectrics. 211:51-66
KNbO3 ceramics were sintered at 1263K thanks to a LiF additive. The ferroelectric-paraelectric transition is of first order and occurs at T c∼670K. A dielectric study in a large frequency ...
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::11a58e1f28d3cddb0ffba1fe65b05cc8
https://doi.org/10.1080/00150199808232333
https://doi.org/10.1080/00150199808232333
Publikováno v:
Journal of Fluorine Chemistry. 84:7-11
Sr 2 ZnGaF 9 is a member of the new tetragonal family Sr 2 M II M III F 9 (M II ≡Mg, Mn, Fe, Co, Ni, Zn; M III ≡Al, Cr, Fe, Ga) with unit cell parameters a =20.04(2) A, c =14.3(1) A, space group I 4 1 22. Two phase transitions have been found in
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::180dfbf8d68e62b71b52ea4354db8ed5
https://doi.org/10.1016/s0022-1139(97)00036-5
https://doi.org/10.1016/s0022-1139(97)00036-5
Publikováno v:
physica status solidi (a). 161:557-564
Dielectric measurements have been performed on a KTN ceramic with composition KTa 0.6 Nb 0.4 O 3 under various dc bias electric fields E. The temperature and field dependences of e' r and tan δ are related to the presence of polarization fluctuation
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::cf8e500ff507392618cd2f5afd4a2ec6
https://doi.org/10.1002/1521-396x(199706)161:2<557::aid-pssa557>3.0.co
https://doi.org/10.1002/1521-396x(199706)161:2<557::aid-pssa557>3.0.co