Results 251 to 260 of about 751,293 (281)

Permeability of complex porous media

Colloid Journal, 2009
Hydrodynamic permeability of membrane composed of a set of porous spherical particles with rigid impenetrable cores is calculated. The cell method proposed by Happel and Brenner is used in calculations. All known boundary conditions on the cell surface, such as the Happel, Kuwabara, Kvashnin, and Cunningham (Mehta-Morse) models, are considered.
S. I. Vasin, A. N. Filippov
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Predicting skin permeability from complex chemical mixtures

Toxicology and Applied Pharmacology, 2005
Occupational and environmental exposure to topical chemicals is usually in the form of complex chemical mixtures, yet risk assessment is based on experimentally derived data from individual chemical exposures from a single, usually aqueous vehicle, or from computed physiochemical properties.
Jim E, Riviere, James D, Brooks
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Parametric modelling of complex permittivity and permeability

1996 IEEE MTT-S International Microwave Symposium Digest, 2002
This paper proposes a new method for measuring the complex permittivity and permeability of materials at microwave frequencies. Starting from reflection/transmission measurements, a parametric model of /spl epsi/ and /spl mu/ is determined using a maximum likelihood estimator.
Van Den Broeck, Tom, Dhondt, Geert, Barel, Alain, Martens, Luc   +3 more
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The permeability transition pore complex: another view

Biochimie, 2002
Mitochondria play a critical role in initiating both apoptotic and necrotic cell death. A major player in this process is the mitochondrial permeability transition pore (MPTP), a non-specific pore, permeant to any molecule of < 1.5 kDa, that opens in the inner mitochondrial membrane under conditions of elevated matrix [Ca(2+)], especially when this is ...
Halestrap, AP, Mcstay, GP, Clarke, SJ
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Complex permeability of polycrystalline hexagonal ferrites

INTERMAG 2000 Digest of Technical Papers. 2000 IEEE International Magnetics Conference, 2000
Polycrystalline hexagonal ferrites (Y, Z and W-phases) were prepared by the usual ceramic sintering. Their complex permeability spectra were natural resonance type, and numerically separated into spin rotational and domain wall motion components. For the spin rotational component, it was found that the Snoek's product values of them were far beyond the
T. Nakamura, K. Hatakeyama
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Complex Permeability Measurements of Microwave Ferrites1

MRS Proceedings, 1996
AbstractA rigorous and accurate method for the experimental determination of the complex permeability of demagnetized ferrites at microwave frequencies is presented. The measurement uses low- loss dielectric ring resonators, is nondestructive, and allows complex permeability characterization of a single ferrite sample to be performed at frequencies ...
Richard G. Geyer, Jerzy Krupka
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Modelling of complex permeability in cores

Le Journal de Physique IV, 1998
In the numerical field analysis a problem that still remains is the development of magnetic parameter models that accurately represents the effect of magnetic anisotropy under complex magnetic conditions. Two modified approaches have been used for the calculation of complex permeability in oriented FeSi lamination. In the first approach pure relaxation
J. Sláma, P. Krivošik, V. Jancárik, E. Ušák   +3 more
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Measurement of complex permittivity and complex permeability of materials

12th International Conference on Microwaves and Radar. MIKON-98. Conference Proceedings (IEEE Cat. No.98EX195), 2002
The time domain measurement of complex permittivity and complex permeability in the 8 to 18 GHz frequency band is considered. Some methods for determination of permittivity and permeability are presented.
H. Alenkowicz, B. Levitas
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Microwave complex permeability and permittivity of nanoferrites

Journal of Applied Physics, 2011
Complex permittivity and permeability of nanosized magnetic powders are studied for eight different bands to cover the frequency range from 2–40 GHz. A precise transmission-reflection based waveguide technique has been used to carry out measurements across the frequency bands. The algorithm for transmission and reflection calculations has been modified
Anjali Sharma, Mohammed N. Afsar
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Using parallel complex permeability for ferrite characterization

International Magnetics Conference, 1989
The authors address topics related to the characterization of linear ferrite materials using real and imaginary components of parallel permeability. Significant advantages are found in using the parallel rather than the usual series form of complex permeability to represent the performance of high-permeability ferrite cores.
J.K. Watson, S. Amoni
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