920 research outputs found
Shock Theory of a Bubbly Liquid in a Deformable Tube
Shock propagation through a bubbly liquid filled in a deformable cylindrical tube is considered. Quasi-one-dimensional
bubbly flow equations that include fluid-structure interaction are formulated, and the steady shock
relations are derived. Experiments are conducted in which a free-falling steel projectile impacts the top of an air/water
mixture in a polycarbonate tube, and stress waves in the tube material are measured. The experimental data indicate
that the linear theory cannot properly predict the propagation speeds of shock waves in mixture-filled tubes; the shock
theory is found to more accurately estimate the measured wave speeds
Shock propagation through a bubbly liquid in a deformable tube
Shock propagation through a bubbly liquid contained in a deformable tube is considered. Quasi-one-dimensional mixture-averaged flow equations that include fluid–structure interaction are formulated. The steady shock relations are derived and the nonlinear effect due to the gas-phase compressibility is examined. Experiments
are conducted in which a free-falling steel projectile impacts the top of an air/water mixture in a polycarbonate tube, and stress waves in the tube material and pressure
on the tube wall are measured. The experimental data indicate that the linear theory is incapable of properly predicting the propagation speeds of finite-amplitude waves
in a mixture-filled tube; the shock theory is found to more accurately estimate the measured wave speeds
Broadband ferromagnetic resonance of Ni81Fe19 wires using a rectifying effect
The broadband ferromagnetic resonance measurement using the rectifying effect
of Ni81Fe19 wire has been investigated. One wire is deposited on the center
strip line of the coplanar waveguide (CPW) and the other one deposited between
two strip lines of CPW. The method is based on the detection of the
magnetoresistance oscillation due to the magnetization dynamics induced by the
radio frequency field. The magnetic field dependences of the resonance
frequency and the rectification spectrum are presented and analytically
interpreted on the standpoint of a uniform magnetization precession model.Comment: 33pages, 8 figures. submitte
Universality in heavy-fermion systems with general degeneracy
We discuss the relation between the T^{2}-coefficient of electrical
resistivity and the T-linear specific-heat coefficient for
heavy-fermion systems with general , where is the degeneracy of
quasi-particles. A set of experimental data reveals that the Kadowaki-Woods
relation; , collapses
remarkably for large-N systems, although this relation has been regarded to be
commonly applicable to the Fermi-liquids. Instead, based on the Fermi-liquid
theory we propose a new relation;
with and .
This new relation exhibits an excellent agreement with the data for whole the
range of degenerate heavy-fermions.Comment: 2 figures, to appear in Phys. Rev. Let
Randomized Controlled Trial of the Effectiveness of Genetic Counseling and a Distance, Computer-Based, Lifestyle Intervention Program for Adult Offspring of Patients with Type 2 Diabetes: Background, Study Protocol, and Baseline Patient Characteristics
Relatives of type 2 diabetic patients are at a high risk of developing type 2 diabetes and should be regarded as target of intervention for diabetes prevention. However, it is usually hard to motivate them to implement preventive lifestyle changes, because of lack of opportunity to take advises from medical professionals, inadequate risk perception, and low priority for preventive behavior. Prevention strategy for them therefore should be highly acceptable and suited for them. The parallel, three-group trial is now being conducted to investigate the effects of genetic counseling and/or a computerized behavioral program on the prevention of type 2 diabetes in that population. The preventive strategies used in this study could provide a novel solution to the numbers of genetically high-risk individuals, if found to be effective. The objective of this paper is to describe the background, protocol, and baseline patient characteristics of the trial
Kondo Effect in an Electron System with Dynamical Jahn-Teller Impurity
We investigate how Kondo phenomenon occurs in the Anderson model dynamically
coupled with local Jahn-Teller phonons. It is found that the total angular
moment composed of electron pseudo-spin and phonon angular moments is screened
by conduction electrons. Namely, phonon degrees of freedom essentially
contribute to the formation of singlet ground state. A characteristic
temperature of the Kondo effect due to dynamical Jahn-Teller phonons is
explained by an effective - Hamiltonian with anisotropic exchange
interaction obtained from the Jahn-Teller-Anderson model in a non-adiabatic
region.Comment: 5 pages, 3 figure
Effect of Anharmonicity on the Kondo Phenomena of a Magnetic Ion Vibrating in a Confinement Potential
Effect of anharmonicity of a cage potential for a magnetic ion vibrating in a
metal is investigated by the numerical renormalization group method. The cage
potential is assumed to be one-dimensional and of the double-well type. In the
absence of the Coulomb interaction, we find continuous crossover among the
three limiting cases: Yu-Anderson-type Kondo regime, the double-well-type Kondo
one, and the renormalized Fermi chain one. In the entire parameter space of the
double-well potential, the ground state is described by a local Fermi liquid.
In the Yu-Anderson-type Kondo regime, a quantum phase transition to the ground
state with odd parity takes place passing through the two-channel Kondo fixed
point when the Coulomb interaction increases. Therefore, the vibration of a
magnetic ion in an oversized cage structure is a promising route to the
two-channel Kondo effect.Comment: 6 pages, 3 figures, accepted for JPS
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