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Full-Text Articles in Physics
Effects Of Second Sound On Acoustic Trasmission At The Solid-Liquid 4He Interface, Matthew J. Moelter, M. B. Manning, C. Elbaum
Effects Of Second Sound On Acoustic Trasmission At The Solid-Liquid 4He Interface, Matthew J. Moelter, M. B. Manning, C. Elbaum
Physics
We have calculated the reflection and transmission coefficients of acoustic waves propagating across a solid-liquid interface of 4He, using an extension of the treatment of Castaing and Nozières in which we include pressure changes associated with second sound. These calculations account well for the experimental results obtained over the temperature range 0.83 K≤ T ≤1.46 K and provide an alternative explanation to the one we offered previously for the lack of agreement between experiment and the theory of Castaing and Nozières.
Magnetite And Magnetotaxis In Algae, F. F. Torres De Araujo, M. A. Pires, Richard B. Frankel, C. E. M. Bicudo
Magnetite And Magnetotaxis In Algae, F. F. Torres De Araujo, M. A. Pires, Richard B. Frankel, C. E. M. Bicudo
Physics
Magnetotactic algae of the genus Anisonema (Euglenophyceae) have been isolated from a coastal mangrove swamp in northeastern Brazil. The magnetotactic response is based on a permanent magnetic dipole moment per cell ~7 10-10 emu. Each cell contains many magnetite (Fe3O4) particles organized in chains.
Science And Society Test Ix: Technical Means Of Verification, David W. Hafemeister
Science And Society Test Ix: Technical Means Of Verification, David W. Hafemeister
Physics
Technical means of monitoring are used to verify compliance to arms control treaties. Numerical estimates are developed in order to quantify some aspects of (1) nuclear testing (signatures, optical double pulse calibration, decoupling in cavities, and high-frequency components in seismic signals), (2) optical reconnaissance (films versus CCDs, air turbulence, adaptive optics, and digital image processing), (3) infrared (resolution and detection sensitivity), and (4) radar (synthetic aperture and missile coefficient).
Rewarding Scientists Who Pursue And Discuss Physics In The Public Interest, David W. Hafemeister, Barbara Levi
Rewarding Scientists Who Pursue And Discuss Physics In The Public Interest, David W. Hafemeister, Barbara Levi
Physics
No abstract provided.
The Cal Poly House Doctor Lab, David W. Hafemeister
Magnetic Skeletons In Davy Jones' Locker, Richard B. Frankel
Carrier-Concentration–Induced Ferromagnetism In Pbsnmnte, T. Story, R. R. Galazka, Richard B. Frankel, P. A. Wolff
Carrier-Concentration–Induced Ferromagnetism In Pbsnmnte, T. Story, R. R. Galazka, Richard B. Frankel, P. A. Wolff
Physics
The influence of charge-carrier concentration on the magnetic properties of the semimagnetic semiconductor [(PbTe)1-x(SnTe)x]1-y[MnTe] y (x=0.72, y=0.03) is reported. Magnetization, magnetic susceptibility, and specific heat have been measured. For carrier concentrations below p=3 x 1020 cm-3 the alloy is paramagnetic. For p≥3 x 1020 cm-3 an abrupt transition to a ferromagnetic phase is observed at helium temperatures. The ferromagnetic transition temperature increases with increasing p. This is the first demonstration of the effect of carrier concentration on the magnetic properties of semimagnetic semiconductors.
Plastic Deformation, Vacancy Diffusion, And Vacancy Delocalization In Bcc 3He, Matthew J. Moelter, M. B. Manning, C. Elbaum
Plastic Deformation, Vacancy Diffusion, And Vacancy Delocalization In Bcc 3He, Matthew J. Moelter, M. B. Manning, C. Elbaum
Physics
The plastic deformation of bcc 3He crystals has been studied near the melting curve, in the temperature range 0.65 K ≤T≤.17 K, and for strain rates, ɛ˙, from 2x10-6 to 2x10-4 sec-1. The resulting relations between strain rate and stress, at a given temperature, are accounted for in terms of dislocation climb and vacancy diffusion in the solid He. The temperature dependence of the strain rate at a given stress indicates that a nonclassical mechanism underlies the deformation process. The vacancy diffusion coefficient in bcc 3He, as a function of temperature, is deduced from …
Biological Effects Of Static Magnetic Fields, Richard B. Frankel
Biological Effects Of Static Magnetic Fields, Richard B. Frankel
Physics
No abstract provided.
Magnetite And Magnetotaxis In Bacteria And Algae, Richard B. Frankel
Magnetite And Magnetotaxis In Bacteria And Algae, Richard B. Frankel
Physics
We are using Mössbauer spectroscopy and magnetic measurements in conjunction with electrochemical, pH and optical spectroscopic measurements to study the mechanisms of iron containing core of these proteins.