Influence of the pulse duration and transient measurement time on the display of the low-frequency dispersion of the earth’s electromagnetic properties for marine waters up to 100 m deep

The purpose of the study is to show the effect of the probe dimensions on the display of the low-frequency dispersion of the geological formations’ electromagnetic properties in transient measurements by electric lines in the axial area of the source for the water areas up to 100 m deep. The study analyzes the change in the transient signal, the finite difference, and the transform (the ratio of the above two) as a function of the length of the source (a horizontal grounded electric line (AB) 50 to 2,000 m), the receiver (a three-electrode electric line (MON) 50 to 2,000 m), and the distance between their centers (spacing) 100 to 4,000 m. The values obtained from the conductive and conductive polarizing models are compared for the identical probes installed at the same depth. The grounded electric line is located within the conducting medium with a conductive polarizable base. The conducting medium is associated with the seawater thickness in the marine shelves up to 100 m deep. The conductive polarizable base is a geological environment (earth) covered with a layer of water. The polarizability of the base is registered by introducing frequency-dependent electrical resistivity by the Cole-Cole formula. The calculations show the display of different transient components associated with the transient buildup and the earth’s low-dispersion properties caused by both galvanic and eddy currents. These components manifest themselves differently for the probes with different dimensions of the source line, receiving line, and spacing. Based on the calculations, it can be argued that in the time range from 1 ms to 16 s, at the probes that have different dimensions and are immersed in the water layer up to 100 m thick, the signal changes depending on the immersion depth for “small” installations (AB of 50 and 100 m), while there is no such dependence for the rest of the probes used in the calculations (AB of 250, 500, 1,000, and 2,000 m).

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Magnetic Permeability and Relaxation Frequency in High Frequency Magnetic Materials.

MRS Proceedings ◽

10.1557/proc-674-u1.8 ◽

2001 ◽

Vol 674 ◽

Cited By ~ 1

Author(s):

M.I. Rosales ◽

H. Montiel ◽

R. Valenzuela

Keyword(s):

High Frequency ◽

Domain Walls ◽

Magnetocrystalline Anisotropy ◽

Low Frequency ◽

Frequency Dispersion ◽

Anisotropy Constant ◽

Relaxation Frequency ◽

Resonance Relaxation ◽

Frequency Behavior

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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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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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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Impedance analysis and low frequency dispersion behavior of Bi4Ti3O12 glass

Journal of the Korean Physical Society ◽

10.3938/jkps.56.462 ◽

2010 ◽

Vol 56 (1(2)) ◽

pp. 462-466 ◽

Cited By ~ 5

Author(s):

YongSuk Yang

Keyword(s):

Low Frequency ◽

Frequency Dispersion ◽

Impedance Analysis ◽

Dispersion Behavior

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Percolative Composites with Carbon Nanohorns: Low-Frequency and Ultra-High Frequency Response

Materials ◽

10.3390/ma12111848 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1848 ◽

Cited By ~ 2

Author(s):

Olga V. Sedelnikova ◽

Kseniya I. Baskakova ◽

Artem V. Gusel’nikov ◽

Pavel E. Plyusnin ◽

Lyubov G. Bulusheva ◽

...

Keyword(s):

Arc Discharge ◽

Thermo Gravimetric Analysis ◽

Low Frequency ◽

Graphite Powder ◽

Electromagnetic Properties ◽

Gravimetric Analysis ◽

Carbon Nanohorns ◽

High Frequency Response ◽

High K Materials ◽

Graphite Rods

We systematically studied the electromagnetic properties of carbon nanohorns (CNHs) and polystyrene composites filled with CNHs in static regime, low frequency and microwave regions. CNHs were synthesized using the direct current arc-discharge method using solid graphite rods and graphite rods filled by melamine mixed with graphite powder. Transmission electron microscopy and thermo-gravimetric analysis showed that CNH agglomerates are the main product, while the addition of melamine promotes the formation of graphite balls. Graphitic contamination causes the internal leakage of inter-agglomerate capacity, lowering the permittivity and enhancing the conductivity of composites. The permittivity of CNH/polystyrene composites increases with the filler fraction, and near the dielectric threshold electromagnetic characteristics of the composites exhibit critical behaviour. Our results suggest that CNHs with relatively high values of permittivity and contact resistance could be used as high-k materials.

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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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