1,028,780 research outputs found
Models for the magnetic ac susceptibility of granular superferromagnetic CoFe/AlO
The magnetization and magnetic ac susceptibility, ,
of superferromagnetic systems are studied by numerical simulations. The
Cole-Cole plot, vs. , is used as a tool for classifying
magnetic systems by their dynamical behavior. The simulations of the
magnetization hysteresis and the ac susceptibility are performed with two
approaches for a driven domain wall in random media. The studies are motivated
by recent experimental results on the interacting nanoparticle system
CoFe/AlO showing superferromagnetic behavior. Its
Cole-Cole plot indicates domain wall motion dynamics similarly to a disordered
ferromagnet, including pinning and sliding motion. With our models we can
successfully reproduce the features found in the experimental Cole-Cole plots.Comment: 8 pages, 6 figure
Identification of the vortex glass phase by harmonics of the AC magnetic susceptibility
We compared the AC magnetic susceptibility behaviour for the vortex glass
phase and for the creep phenomena with an inhomogeneous pinning potential. The
temperature dependence of the harmonics of the susceptibility have been
numerically simulated with these two models, and we studied them as a function
of the frequency, in terms of Cole-Cole plots. From our analysis we show that
it is possible to distinguish between the two different phases, because of
their clear differences in the Cole-Cole plots behaviour with the frequency.Comment: 8 pages, 2 figures to be published on "The Journal of Physics and
Chemistry of Solids
Cole (1989)
Music and Lyrics: Cole Porter
Director/Choreographer: Janie Scott
Musical Director: Dwight Cannon
Set Design: Dusty Reeds
Costumes: Elizabeth M. Poindexter
Academic Year: 1989-1990https://scholarworks.sjsu.edu/productions_1990s/1022/thumbnail.jp
Absence of self-averaging in the complex admittance for transport through random media
A random walk model in a one dimensional disordered medium with an
oscillatory input current is presented as a generic model of boundary
perturbation methods to investigate properties of a transport process in a
disordered medium. It is rigorously shown that an admittance which is equal to
the Fourier-Laplace transform of the first-passage time distribution is
non-self-averaging when the disorder is strong. The low frequency behavior of
the disorder-averaged admittance, where , does not coincide with the low frequency behavior of the admittance for any
sample, . It implies that the Cole-Cole plot of
appears at a different position from the Cole-Cole plots of of any
sample. These results are confirmed by Monte-Carlo simulations.Comment: 7 pages, 2 figures, published in Phys. Rev.
Structural relaxation in the hydrogen-bonding liquids N-methylacetamide and water studied by optical Kerr-effect spectroscopy
Structural relaxation in the peptide model N-methylacetamide (NMA) is studied
experimentally by ultrafast optical Kerr-effect spectroscopy over the
normal-liquid temperature range and compared to the relaxation measured in
water at room temperature. It is seen that in both hydrogen-bonding liquids,
beta relaxation is present and in each case it is found that this can be
described by the Cole-Cole function. For NMA in this temperature range, the
alpha and beta relaxations are each found to have an Arrhenius temperature
dependence with indistinguishable activation energies. It is known that the
variations on the Debye function, including the Cole-Cole function, are
unphysical, and we introduce two general modifications: one allows for the
initial rise of the function, determined by the librational frequencies, and
the second allows the function to be terminated in the alpha relaxation
Determination of Electrical Parameters for Skin during Galvanic Skin Reflex from Continuous Measurement
Skin impedance satisfies the Cole-Cole arc's law. The change of skin impedance during GSR (Galvanic Skin Reflex) can be expressed by the change of equivalent parallel resistance approximately. Using these characteristics, the complicated change of skin impedance during GSR can be determined continuously from the measurement value in one frequency point
Leveraging Bias in Forensic Science
Dr. Simon Cole calls for a more hierarchical organization of forensic science in his challenging Article, Acculturating Forensic Science: What is ‘Scientific Culture’, and How can Forensic Science Adopt it? Koppl thinks Dr. Cole is right to say that there are different roles in forensic science, but somewhat mistaken in his call for hierarchy
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