36,475 research outputs found
Molding a high-density laminate
Molding press is used to form phenolic resin impregnated glass fiber cloth into a high-density, cylindrical-ring laminate. The press applies clamping pressure and heat to a mold containing the glass fiber cloth laminate, which has hydrostatic pressure applied to it by means of a specially designed pressure plug
Comments on “Electric current and electric field induced in a human body when exposed to an incident electric field near the resonant frequency”
[For original paper see R. W. P. King, IEEE Trans. Microwave Theory Tech., vol. 48, no. 9, pp. 147-53 (2000).] The author makes two observations on the original article. The commentator questions whether a seated person is well modeled as a right circular cylinder. The second observation is that King cites only microwave studies on mice to show that electromagnetic radiation causes malignancies. These studies themselves are widely disputed. He then uses simple dimensional scaling to show that 2.45 GHz for a mouse scales to 100 MHz for a man. Such a scaling law may be useful in calculating the resonant frequency for a human subject versus a mouse when treated as antennas, but such scaling is meaningless when the physics of a hypothetical carcinogenic process are unknown
Library Economic Metrics: Examples of the Comparison of Electronic and Print Journal Collections and Collection Services
published or submitted for publicatio
Late Miocene to early Pliocene stratigraphic record in northern Taranaki Basin: Condensed sedimentation ahead of Northern Graben extension and progradation of the modern continental margin
The middle Pliocene-Pleistocene progradation of the Giant Foresets Formation in Taranaki Basin built up the modern continental margin offshore from western North Island. The late Miocene to early Pliocene interval preceding this progradation was characterised in northern Taranaki Basin by the accumulation of hemipelagic mudstone (Manganui Formation), volcaniclastic sediments (Mohakatino Formation), and marl (Ariki Formation), all at bathyal depths. The Manganui Formation has generally featureless wireline log signatures and moderate to low amplitude seismic reflection characteristics. Mohakatino Formation is characterised by a sharp decrease in the GR log value at its base, a blocky GR log motif reflecting sandstone packets, and erratic resistivity logs. Seismic profiles show bold laterally continuous reflectors. The Ariki Formation has a distinctive barrel-shaped to blocky GR log motif. This signature is mirrored by the SP log and often by an increase in resistivity values through this interval. The Ariki Formation comprises (calcareous) marl made up of abundant planktic foraminifera, is 109 m thick in Ariki-1, and accumulated over parts of the Western Stable Platform and beneath the fill of the Northern Graben. It indicates condensed sedimentation reflecting the distance of the northern region from the contemporary continental margin to the south
Relativistic, QED, and finite nuclear mass corrections for low-lying states of Li and Be
Accurate results for nonrelativistic energy, relativistic, QED, and finite
nuclear mass corrections are obtained for , and
states of the Li atom and Be ion. Our computational approach
uses the Hylleraas basis set with the analytic integration and recursion
relations. From comparison of experimental results for the isotope shifts to
theoretical predictions including nuclear polarizabilities, we obtain nuclear
charge radii for Li and Be isotopes.Comment: 19 pages, 8 tables, Phys. Rev. A in prin
Constraining Mass Spectra with Sterile Neutrinos from Neutrinoless Double Beta Decay, Tritium Beta Decay and Cosmology
We analyze the constraints on neutrino mass spectra with extra sterile
neutrinos as implied by the LSND experiment. The various mass related
observables in neutrinoless double beta decay, tritium beta decay and cosmology
are discussed. Both neutrino oscillation results as well as recent cosmological
neutrino mass bounds are taken into account. We find that some of the allowed
mass patterns are severely restricted by the current constraints, in particular
by the cosmological constraints on the total sum of neutrino masses and by the
non-maximality of the solar neutrino mixing angle. Furthermore, we estimate the
form of the four neutrino mass matrices and also comment on the situation in
scenarios with two additional sterile neutrinos.Comment: 40 pages, 9 figures. Minor changes, matches version in PR
Applying the Ablative Heat Shield to the Apollo Spacecraft
The Apollo program to land men on the moon is administered by the National Aeronautics and Space Administration. Production of the spacecraft command module has been assigned \u27to the North American Aviation Company. As a subcontractor to N.A.A., the Avco Corporation is carrying out the design and fabrication of the ablative heat shield for this module. Avco has the responsibility for the complete thermal design of the heat shield and for the analysis of any structural effect of the ablative material on the total vehicle. The environmental requirements which the heat shield must satisfy are determined by North American.
The Apollo spacecraft command module houses the three-man crew during flight and is the only part of the spacecraft to re-enter the earth\u27s atmosphere at the completion of the lunar mission. It is a cone-shaped vehicle with a blunt base and is composed of an airtight aluminum inner crew compartment suspended within a stainless steel outer shell
Long-term monitoring of Molonglo calibrators
Before and after every 12 hour synthesis observation, the Molonglo
Observatory Synthesis Telescope (MOST) measures the flux densities of ~5
compact extragalactic radio sources, chosen from a list of 55 calibrators. From
1984 to 1996, the MOST made some 58 000 such measurements. We have developed an
algorithm to process this dataset to produce a light curve for each source
spanning this thirteen year period. We find that 18 of the 55 calibrators are
variable, on time scales between one and ten years. There is the tendency for
sources closer to the Galactic Plane to be more likely to vary, which suggests
that the variability is a result of refractive scintillation in the Galactic
interstellar medium. The sources with the flattest radio spectra show the
highest levels of variability, an effect possibly resulting from differing
orientations of the radio axes to the line of sight.Comment: 18 pages, 9 embedded EPS files. To appear in Publications of the
Astronomical Society of Australia. Data available electronically at
http://www.physics.usyd.edu.au/astrop/scan
Simplified quantum logic with trapped ions
We describe a simplified scheme for quantum logic with a collection of
laser-cooled trapped atomic ions. Building on the scheme of Cirac and Zoller,
we show how the fundamental controlled-NOT gate between a collective mode of
ion motion and the internal states of a single ion can be reduced to a single
laser pulse, and the need for a third auxiliary internal electronic state can
be eliminated.Comment: 8 pages, PostScript, submitted to Physical Review A, Rapid
Communication
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