Broad-band dielectric spectroscopy of low-permittivity fluids using one measurement cell

1998 ◽  
Vol 47 (4) ◽  
pp. 881-885 ◽  
Author(s):  
K. Folgero
Keyword(s):  
Dielectric Spectroscopy ◽  
Broad Band ◽  
Measurement Cell ◽  
Low Permittivity

Broad-Band Dielectric Spectroscopy of PZN-8%PT Single Crystal

2005 ◽  
Vol 318 (1) ◽  
pp. 179-183 ◽  
Author(s):  
Viktor Bovtun ◽  
Sergiy Veljko ◽  
Maxim Savinov ◽  
Alexej Pashkin ◽  
Stanislav Kamba ◽  
...  
Keyword(s):  
Single Crystal ◽  
Dielectric Spectroscopy ◽  
Broad Band

Broad-band dielectric spectroscopy analysis of relaxational dynamics in Mn-dopedSrTiO3ceramics

2006 ◽  
Vol 73 (10) ◽  
Author(s):  
A. Tkach ◽  
P. M. Vilarinho ◽  
A. L. Kholkin ◽  
A. Pashkin ◽  
S. Veljko ◽  
...  
Keyword(s):  
Dielectric Spectroscopy ◽  
Broad Band ◽  
Spectroscopy Analysis

Segmental Dynamics in Poly(vinylethylene)/Polyisoprene Miscible Blends Revisited. A Neutron Scattering and Broad-Band Dielectric Spectroscopy Investigation

1999 ◽  
Vol 32 (22) ◽  
pp. 7572-7581 ◽  
Author(s):  
A. Arbe ◽  
A. Alegría ◽  
J. Colmenero ◽  
S. Hoffmann ◽  
L. Willner ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Dielectric Spectroscopy ◽  
Broad Band ◽  
Segmental Dynamics ◽  
Miscible Blends

Broad-band dielectric spectroscopy and ferroelectric soft-mode response in the Ba0.6Sr0.4TiO3solid solution

2009 ◽  
Vol 21 (47) ◽  
pp. 474215 ◽  
Author(s):  
T Ostapchuk ◽  
J Petzelt ◽  
J Hlinka ◽  
V Bovtun ◽  
P Kužel ◽  
...  
Keyword(s):  
Dielectric Spectroscopy ◽  
Soft Mode ◽  
Broad Band ◽  
Mode Response

Pressure and temperature dependences of the dynamics of glass formers studied by broad-band dielectric spectroscopy

2002 ◽  
Vol 82 (6) ◽  
pp. 651-662 ◽  
Author(s):  
S. Capaccioli ◽  
M. Lucchesi ◽  
R. Casalini ◽  
S. Presto ◽  
P. A. Rolla ◽  
...  
Keyword(s):  
Dielectric Spectroscopy ◽  
Broad Band ◽  
Temperature Dependences

Application of Broad-Band Dielectric Spectroscopy for Investigations of Liquid Crystal - Porous Media Microcomposites

1997 ◽  
Vol 500 ◽  
Author(s):  
G. P. Sinha ◽  
B. Batalla ◽  
F. M. Aliev
Keyword(s):  
Dielectric Properties ◽  
Dielectric Spectroscopy ◽  
Volume Fraction ◽  
Broad Band ◽  
Interfacial Polarization ◽  
Pore Wall ◽  
Slow Process ◽  
Frequency Range ◽  
Average Pore ◽  
Hindered Rotation

ABSTRACTWe applied ultra broad-band dielectric spectroscopy in the frequency range from 10–3 Hz to 109 Hz to investigate the effect of size, shape and volume fraction of the pores in the porous matrices on the dielectric properties of liquid crystals (LC) dispersed in these matrices. Measurements in such a broad frequency range make it possible to obtain detailed information on the important aspects of the electrical behavior of heterogeneous materials such as: conductivity, surface polarization, and influence of confinement on dynamics of molecular motion of polar molecules forming LC. We investigated alkylcyanobiphenyls in the isotropie, nematic and smectic phases dispersed in porous glasses (average pore sizes - 100 Å and 1000 Å) which have randomly oriented, interconnected pores, and anopore membranes (pore diameters - 200 Å and 2000 Å) with parallel cylindrical pores. Dispersion of LC resulted in qualitative changes of their dielectric properties. Analysis of broad-band dielectric spectra shows that in organic (LC) - inorganic (porous matrix) heterogeneous composites conductivity plays an important role at F <1 Hz. We observe the appearance of new dielectric modes: a very slow process with characteristic frequency ≃ (1 – 10) Hz and a second process in frequency range about (103 - 106) Hz. The slow process arises due to the relaxation of interfacial polarization at pore wall - LC interface. The origin of this could be due to absorption of ions at the interface. Another possibility is the preferential orientation of the permanent dipoles at pore surface. The second new mode is due to the hindered rotation of the molecules near the interface. Additionally we observed two bulk like modes due to the rotation of the molecules around their short and long axii which are modified.

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