111 research outputs found
High Dielectric Permittivity in AFeBO Nonferroelectric Perovskite Ceramics (A - Ba, Sr, Ca; B - Nb, Ta, Sb)
AFeBO(A- Ba, Sr, Ca; B-Nb, Ta, Sb) ceramics were
synthesized and temperature dependencies of the dielectric permittivity were
measured at different frequencies. The experimental data obtained show very
high values of the dielectric permittivity in a wide temperature interval that
is inherent to so-called high-k materials. The analyses of these data establish
a Maxwell-Wagner mechanism as a main source for the phenomenon observed.Comment: 6 pages, 7 figure
Study of the Physical Properties and Electrocaloric Effect in the BaTiO3 Nano- and Microceramics
The specific heat, thermal expansion, permittivity, and electrocaloric effect in bulk of BaTiO3 (BT) samples in the form of nano- (nBT-500 nm) and micro- (mBT-1200 nm) ceramics fabricated using spark plasma sintering and solid-state plasma techniques have been investigated. The size effect has been reflected, to a great extent, in the suppression of the specific heat and thermal expansion anomalies and in the changes in the temperatures and entropies of phase transitions and permittivity, and a decrease in the maximum intensive electrocaloric effect: ΔTmaxAD = 29 mK (E = 2.0 kV/cm) for nBT and ΔTmaxAD = 70 mK (E = 2.5 kV/cm) for mBT. The conductivity growth at temperatures above 360 K leads to the significant irreversible heating of the samples due to the Joule heat release in the applied electric field, which dominates over the electrocaloric effect
Elastic and anelastic relaxation behaviour of perovskite multiferroics II: PbZr0.53Ti0.47O3 (PZT)–PbFe0.5Ta0.5O3 (PFT)
Peculiarities of the dielectric, elastic, and anelastic properties of the PbFe1/2Nb1/2O3 ferroelectromagnet at the antiferromagnetic phase transition
The main feature of the guide structures described by non-self-conjugate electrodynamic operators
Molecular structure of 2,3-(4?-phenylacetyl)- and 2,3-(4?-diphenylacetyl)-benzo-15-crown-5
Electric Field–Induced Birefringence in Pb[sub 0.94]Ba[sub 0.06]Sc[sub 0.5]Nb[sub 0.5]O[sub 3] (PBSN–6) Solid-Solution Single Crystals
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