2,630 research outputs found
Operation of hydrodynamic journal bearings in sodium at temperatures to 800 deg F and speeds to 12000 rpm
Operation of hydrodynamic journal bearings in liquid sodium at high temperatures and high speed
Exploding lakes in Vanuatu - "Surtseyan-style" eruptions witnessed on Ambae Island
After a long silence, Lake Vui on Ambae Island burst into spectacular life on the 28th of November 2005, disrupting the lives of 10 000 inhabitants on this sleepy tropical island in the SW Pacific. "Surtseyan- style" explosions burst through the Island's summit lake waters forming a new tuff-cone and threatening to form deadly lahars or volcanic floods. Such eruptions are rarely well observed, and these fleeting opportunities provide a chance to match volcanic processes with rock-sequences found commonly in the geologic recor
Hot subdwarf stars and their connection to thermonuclear supernovae
Hot subdwarf stars (sdO/Bs) are evolved core helium-burning stars with very
thin hydrogen envelopes, which can be formed by common envelope ejection. Close
sdB binaries with massive white dwarf (WD) companions are potential progenitors
of thermonuclear supernovae type Ia (SN Ia). We discovered such a progenitor
candidate as well as a candidate for a surviving companion star, which escapes
from the Galaxy. More candidates for both types of objects have been found by
crossmatching known sdB stars with proper motion and light curve catalogues.
The Gaia mission will provide accurate astrometry and light curves of all the
stars in our hot subdwarf sample and will allow us to compile a much larger
all-sky catalogue of those stars. In this way we expect to find hundreds of
progenitor binaries and ejected companions.Comment: Proceedings of the 11th Pacific Rim Conference on Stellar
Astrophysics, Hong Kong 2015, Journal of Physics: Conference Series, in pres
KIC7668647: a 14 day beaming sdB+WD binary with a pulsating subdwarf
The recently discovered subdwarf B (sdB) pulsator KIC7668647 is one of the 18
pulsating sdB stars detected in the Kepler field. It features a rich g-mode
frequency spectrum, with a few low-amplitude p-modes at short periods.
We use new ground-based low-resolution spectroscopy, and the near-continuous
2.88 year Kepler lightcurve, to reveal that KIC7668647 consists of a subdwarf B
star with an unseen white-dwarf companion with an orbital period of 14.2d. An
orbit with a radial-velocity amplitude of 39km/s is consistently determined
from the spectra, from the orbital Doppler beaming seen by Kepler at 163ppm,
and from measuring the orbital light-travel delay of 27 by timing of the many
pulsations seen in the Kepler lightcurve. The white dwarf has a minimum mass of
0.40 M_sun.
We use our high signal-to-noise average spectra to study the atmospheric
parameters of the sdB star, and find that nitrogen and iron have abundances
close to solar values, while helium, carbon, oxygen and silicon are
underabundant relative to the solar mixture.
We use the full Kepler Q06--Q17 lightcurve to extract 132 significant
pulsation frequencies. Period-spacing relations and multiplet splittings allow
us to identify the modal degree L for the majority of the modes. Using the
g-mode multiplet splittings we constrain the internal rotation period at the
base of the envelope to 46-48d as a first seismic result for this star. The few
p-mode splittings may point at a slightly longer rotation period further out in
the envelope of the star.
From mode-visibility considerations we derive that the inclination of the
rotation axis of the sdB in KIC7668647 must be around ~60 degrees.
Furthermore, we find strong evidence for a few multiplets indicative of
degree 3 <= L <= 8, which is another novelty in sdB-star observations made
possible by Kepler.Comment: arXiv admin note: text overlap with arXiv:1206.387
The Courtship Associated Sounds of Nassau grouper, Epinephelus striatus (Pisces: Epinephelidae) during Spawning Aggregations
The population of hot subdwarf stars studied with Gaia I. The catalogue of known hot subdwarf stars
In preparation for the upcoming all-sky data releases of the Gaia mission we
compiled a catalogue of known hot subdwarf stars and candidates drawn from the
literature and yet unpublished databases. The catalogue contains 5613 unique
sources and provides multi-band photometry from the ultraviolet to the far
infrared, ground based proper motions, classifications based on spectroscopy
and colours, published atmospheric parameters, radial velocities and light
curve variability information. Using several different techniques we removed
outliers and misclassified objects. By matching this catalogue with astrometric
and photometric data from the Gaia mission, we will develop selection criteria
to construct a homogeneous, magnitude-limited all-sky catalogue of hot subdwarf
stars based on Gaia data.Comment: 11 pages, A&A accepte
On the off-axis tensile test for unidirectional composites
The off axis tensile test was examined experimentally to obtain actual displacement fields over the surface of graphite polyimide coupon specimens. The experimental results were compared with approximate analytical solutions and generated finite element results. An optical method of high sensitivity moire interferometry was used to determine the actual displacements to high precision. The approximate analytical solution and the finite element results compare very favorably with the measured centerline displacements in the test section, and the finite element displacement fields provide excellent agreement with the moire displacements throughout the specimen. A 15 degree fiber orientation and coupon aspect ratios of 5 and 15 are presented
Community Emergency Management During the 2005 Ambae Eruption, Vanuatu, SW Pacific.
No abstract availabl
A fagyasztott zöldségek fogyasztási preferenciáinak vizsgálata
A magyar hűtÅ‘ipar számára a külföldi piacokon való értékesÃtés nagy jelentÅ‘ségű. A hűtÅ‘ipar talán az egyetlen ágazat, melynek termelése minÅ‘ségileg sosem különült el az értékesÃtés piacai szerint, köszönhetÅ‘en annak, hogy a vertikumban a nemzetközi követelmények érvényesültek. A komplex vásárlói modellek elemzését követÅ‘en megállapÃtható, hogy az ÃzesÃtett termékeket leginkább az aktÃv szellemi foglalkozásúak részesÃtik elÅ‘nyben, akik átlag feletti jövedelemmel rendelkeznek. Az ÃzesÃtett termékek és a vegyes összetevÅ‘jű (mix) termékek tipikus vásárlója között nem tapasztalható jelentÅ‘s eltérés. A vizsgálat eredményei alapján az a következtetés vonható le, hogy az egy összetevÅ‘jű termékek vásárlói között a legalacsonyabb a férfiak és a legmagasabb a nÅ‘k, valamint a középfokú végzettségűek aránya. --------------------------------------------- The marketing of products in foreign markets is of paramount importance for the Hungarian deep freeze industry. The deep freeze industry may be the only sector where the quality of products has never varied according to the target market, as the product chain is ruled by international requirements. The analysis of complex customer models leads us to conclude that flavoured products were favoured by mostly persons of white collar vocations, who have an above average in come. No significant discrepancies were perceived between the typical customers of flavoured products and products of mixed ingredients. Based on the results of the analysis it can be stated that among the customers choosing products consisting of one component only, the ratio of men was lowest whereas that of women and persons having secondary education was highest.mélyhűtÅ‘ipar, fagyasztott élelmiszer, export, fogyasztói magatartás, vásárlási szokások, deep freeze industry, frozen food, export, consumer behaviour, customer habits, Consumer/Household Economics, Marketing,
A large-scale, near-sea level, silicic caldera-forming eruption in Efate? An alternative model for the 1 Ma Efate Pumice Formation, Vanuatu, SW-Pacific
No abstract availabl
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