Impedance analysis and low frequency dispersion behavior of Bi4Ti3O12 glass

ABSTRACTAn investigation of the frequency behavior of polycrystalline ferrites is presented. It is shown that the low frequency dispersion (f < 10 MHz) of permeability is associated with the bulging of pinned domain walls, and has a mixed resonance-relaxation character, closer to the latter. It is also shown that there is a linear relationship between the magnetocrystalline anisotropy constant, K1, and the relaxation frequency. The slope of this correlation depends on the grain size. Such a relationship could allow the determination of this basic parameter from polycrystalline samples.

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Dielectric frequency dispersion behavior in flux grown PbTiO3single crystals

Ferroelectrics ◽

10.1080/00150199208230011 ◽

1992 ◽

Vol 135 (1) ◽

pp. 39-48 ◽

Cited By ~ 21

Author(s):

X. H. Dai ◽

Z. Li ◽

X. Z. Xu ◽

S-K. Chan ◽

D. J. Lam

Keyword(s):

Frequency Dispersion ◽

Dispersion Behavior

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Volume low-frequency dispersion in a semi-insulating system

IEEE Transactions on Electrical Insulation ◽

10.1109/14.2356 ◽

1988 ◽

Vol 23 (2) ◽

pp. 209-213 ◽

Cited By ~ 6

Author(s):

A.K. Jonscher ◽

L. Levesque

Keyword(s):

Low Frequency ◽

Frequency Dispersion

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An Impedance Study of the Membrane Polarisation Effect in Simulated Rock Systems

10.26686/wgtn.16999279.v1 ◽

2021 ◽

Author(s):

◽

Michael Charles Harold McKubre

Keyword(s):

Low Frequency ◽

Impedance Measurement ◽

Impedance Analysis ◽

Laboratory Model ◽

Pore Geometry ◽

Impedance Spectra ◽

Clay Rock ◽

Polarisation Effect ◽

Diffusional Limitation ◽

Electrochemical Model

<p>Work is reported on the development of a high precision, low frequency impedance bridge, and the use of impedance measurement in characterising the induced polarisation effect of unmineralised material. Impedance spectra for a variety of laboratory model clay/rock/electrolyte systems are analysed in terms of an equivalent circuit. By measuring the dependence of the parameters of this circuit, on such variables as electrolyte type and concentration, temperature and pore geometry, an electrochemical model for membrane polarisation has been developed. Polarisation is considered to arise from diffusional limitation of cations at the membrane/electrolyte interface of clay aggregations in rock pores, and this is found to be amenable to a Warburg diffusional impedance analysis.</p>

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Low frequency dispersion in the dielectric response of HTV silicone rubber

2017 1st International Conference on Electrical Materials and Power Equipment (ICEMPE) ◽

10.1109/icempe.2017.7982045 ◽

2017 ◽

Author(s):

Gao Yanfeng ◽

Liang Xidong

Keyword(s):

Silicone Rubber ◽

Dielectric Response ◽

Low Frequency ◽

Frequency Dispersion

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Theory of the ferroelectric Mott-Hubbard phase in organic conductors

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:20020382 ◽

2002 ◽

Vol 12 (9) ◽

pp. 149-152

Author(s):

S. Brazovskii

Keyword(s):

Activation Energy ◽

Phase Transitions ◽

Low Frequency ◽

Frequency Dispersion ◽

Organic Conductors ◽

The State ◽

Charge Disproportionation ◽

Subsequent Phase

Recently the ferroelectric FE anomaly (Nad, Monceau, et al.) followed by the charge disproportionation CD (Brown, et al) have been discovered in ($TMTTF)_2X$ compounds. A theory of the combined Mott-Hubbard state describes both effects by interference of the build-in nonequivalence of bonds and the spontaneous one of sites. The state gives rise to three types of solitons: $\pi -$ solitons (holons) are observed via the activation energy A in conductivity G; noninteger $\alpha -$ solitons provide the frequency dispersion of the FE response; combined spin-charge solitons determine $G(T)$ below subsequent phase transitions. The optical edge lies well below the conductivity gap 2A; the critical FE mode coexists with a combined electron-phonon resonance and a phonon antiresonance. The CD and the FE can exists hiddenly even in the Se subfamily giving rise to the unexplained yet low frequency optical peak, the enhanced pseudogap and traces of phonons activation.

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Bioimpedance Analysis of L929 and HaCaT Cells in Low Frequency Range

Current Directions in Biomedical Engineering ◽

10.1515/cdbme-2018-0029 ◽

2018 ◽

Vol 4 (1) ◽

pp. 115-118 ◽

Cited By ~ 5

Author(s):

Viviane S. Teixeira ◽

Jan-Patrick Kalckhoff ◽

Wolfgang Krautschneider ◽

Dietmar Schroeder

Keyword(s):

Low Frequency ◽

Steel Corrosion ◽

Frequency Dispersion ◽

Human Keratinocytes ◽

Cell Types ◽

Hacat Cells ◽

Frequency Range ◽

Corrosion Resistant ◽

L929 Mouse

AbstractIn this work, Bioimpedance Spectroscopy (BIS) is used to study fluids and cell solutions. A n ew fourelectrode- terminal (4T) chamber using 3D printing and stainless steel corrosion resistant V4A was designed to measure the impedance of live cell solutions at the frequency range 0.1Hz- 1MHz. At f < 1kHz the double layer (DL) that builds at electrode’s surface raises the impedance substantially preventing the observation of the real impedance of the cells. The new 4T design circumvents the DL, is more robust and cheap, and allows for the repeatability of the results. Experiments were performed in vitro with two cell lines, L929 (mouse fibroblasts) and HaCaT (human keratinocytes). Results show that it is possible to distinguish between the two cell types by means of its BIS measurements in the new setup. Also, a low-frequency dispersion (α-dispersion) was observed in HaCaT cells solution, but not in L929. Furthermore, a potentiostat circuit model was developed in LTSpice to simulate the hardware setup and two different circuit models were used to fit cell’s data.

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