13,752 research outputs found
Heat sterilizable Ni-Cd battery development Quarterly progress report, 1 Oct. - 31 Dec. 1967
Microscopic, X ray diffraction, porosity, and pore size distribution data for heat sterilizable Ni-Cd batter
Heat sterilizable Ni-Cd battery development Quarterly report, 1 Jul. - 30 Sep. 1967
Effect of heat sterilization on electrochemistry of nickel-cadmium batterie
Extra dimensions as a source of the electroweak model
The Higgs boson of the Standard model is described by a set of off-diagonal
components of the multidimensional metric tensor, as well as the gauge fields.
In the low-energy limit, the basic properties of the Higgs boson are
reproduced, including the shape of the potential and interactions with the
gauge fields of the electroweak part of the Standard model.Comment: 11 pages, revtex4. Some wording changed, misprints corrected, 1
reference adde
Late-time Phase transition and the Galactic halo as a Bose Liquid: (II) the Effect of Visible Matter
In the previous work, we investigated the rotation curves of galaxies
assuming that the dark matter consists of ultra light boson appearing in
late time phase transition' theory. Generalizing this work, we consider the
effect of visible matter and classify the types of rotation curves as we vary
the fraction of the mass and extention of visible matter. We show that visible
matter, in galaxies with flat rotation curves, has mass fraction and it is confined within the distance fraction .Comment: 10 pages, 10 figures included, to appear in Phys. Rev. D50,p365
Shock-Wave Heating Model for Chondrule Formation: Prevention of Isotopic Fractionation
Chondrules are considered to have much information on dust particles and
processes in the solar nebula. It is naturally expected that protoplanetary
disks observed in present star forming regions have similar dust particles and
processes, so study of chondrule formation may provide us great information on
the formation of the planetary systems.
Evaporation during chondrule melting may have resulted in depletion of
volatile elements in chondrules. However, no evidence for a large degree of
heavy-isotope enrichment has been reported in chondrules. In order to meet this
observed constraint, the rapid heating rate at temperatures below the silicate
solidus is required to suppress the isotopic fractionation.
We have developed a new shock-wave heating model taking into account the
radiative transfer of the dust thermal continuum emission and the line emission
of gas molecules and calculated the thermal history of chondrules. We have
found that optically-thin shock waves for the thermal continuum emission from
dust particles can meet the rapid heating constraint, because the dust thermal
emission does not keep the dust particles high temperature for a long time in
the pre-shock region and dust particles are abruptly heated by the gas drag
heating in the post-shock region. We have also derived the upper limit of
optical depth of the pre-shock region using the radiative diffusion
approximation, above which the rapid heating constraint is not satisfied. It is
about 1 - 10.Comment: 58 pages, including 5 tables and 15 figures, accepted for publication
in The Astrophysical Journa
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