47,597 research outputs found
Two-axis winch installer for heavy ducts in confined space
Two-axis winching and traversing device is used for installing liquid-propellant rocket-engine fuel and liquid oxygen suction ducts between the valves and the rocket engine on a test stand. The device raises and maneuvers the duct into the required position where it can be safely installed by mechanics
Cynthia L. Horn, Plaintiff, v. Knight Facilities Management -- GM, Inc., a Delaware corporation, Defendant.
Dense molecular clouds in the SN2008fp host galaxy
(abridged) We use observations of interstellar absorption features, such as
atomic and molecular lines as well as diffuse interstellar bands (DIBs),
towards SN2008fp to study the physical properties of extra-galactic diffuse
interstellar clouds in the host galaxy, ESO428-G14. The properties of the
intervening dust are investigated via spectropolarimetry. The spectra of
SN2008fp reveal a complex of diffuse atomic clouds at radial velocities in line
with the systematic velocities of the host galaxy (~1700 km/s). A translucent
(A_V ~ 1.5 mag) cloud is detected at a heliocentric velocity of 1770 km/s This
cold dense cloud is rich in dense atomic gas tracers, molecules, as well as
diffuse interstellar bands. We have detected both C2 and C3 for the first time
in a galaxy beyond the Local Group. The CN (0,0) band line ratios are used to
derive an in-situ measurement of the cosmic background radiation temperature in
an external galaxy; this gives an excitation temperature of T = 2.9 +- 0.3 K.
The interstellar polarization law deviates significantly from what is observed
in the Galaxy, indicating substantial differences in the composition or size
distribution of dust grains in the SN2008fp host galaxy. C2 is used to probe
the cold diffuse ISM density and temperature. The lack of variability in the
extra-galactic absorption line profiles over a period of one month implies that
the absorbing material is not circumstellar and thus not affected directly by
the SN event. Also it shows that there are no significant density variation in
the small-scale structure of the molecular cloud down to 100 AU.Comment: 10 pages. Accepted for publication in A&A. Revisions include several
small correction
Implications of Hydrocarbon and Helium Gas Analyses of Springs from the Ouachita Mountains, Arkansas
One hundred and three ground water samples (predominantly springs) were analyzed for headspace light hydrocarbon gases and helium. Four of the formations (Arkansas Novaculite, Bigfork Chert, Stanley Shale, and Womble) having the highest mean methane values are the only Ouachita Mountain facies to produce petroleum or exhibit marginally commercial production. This observation suggests that the mean methane values are useful as an indication of the relative hydrocarbon content of these formations Anomalous helium values are generally associated with mapped faults
Fully automatic telemetry data processor
Satellite Telemetry Automatic Reduction System /STARS 2/, a fully automatic computer-controlled telemetry data processor, maximizes data recovery, reduces turnaround time, increases flexibility, and improves operational efficiency. The system incorporates a CDC 3200 computer as its central element
High-resolution [C II] imaging of HDF850.1 reveals a merging galaxy at z=5.185
New high-resolution maps with the IRAM Interferometer of the redshifted [C
II] 158 micron line and the 0.98mm dust continuum of HDF850.1 at z = 5.185 show
the source to have a blueshifted northern component and a redshifted southern
component, with a projected separation of 0.3 arcsec, or 2 kpc. We interpret
these components as primordial galaxies that are merging to form a larger
galaxy. We think it is the resulting merger-driven starburst that makes
HDF850.1 an ultraluminous infrared galaxy, with an L(IR) of 1E13 Lsun. The
observed line and continuum brightness temperatures and the constant
line-to-continuum ratio across the source imply (1) high [C II] line optical
depth, (2) a [C II] excitation temperature of the same order as the dust
temperature, and (3) dust continuum emission that is nearly optically thick at
158 microns. These conclusions for HDF850.1 probably also apply to other
high-redshift submillimeter galaxies and quasar hosts in which the [C II] 158
micron line has been detected, as indicated by their roughly constant [C
II]-to-158 micron continuum ratios, in sharp contrast to the large dispersion
in their [C II]-to-FIR luminosity ratios. In brightness temperature units, the
[C II] line luminosity is about the same as the predicted CO(1-0) luminosity,
implying that the [C II] line can also be used to estimate the molecular gas
mass, with the same assumptions as for CO.Comment: Accepted by Astronomy and Astrophysic
Extraordinary nonlinear plasmonics in graphene nanoislands
Nonlinear optical processes rely on the intrinsically weak interactions
between photons enabled by their coupling with matter. Unfortunately, many
applications in nonlinear optics are severely hindered by the small response of
conventional materials. Metallic nanostructures partially alleviate this
situation, as the large light enhancement associated with their localized
plasmons amplifies their nonlinear response to record high levels. Graphene
hosts long-lived, electrically tunable plasmons that also interact strongly
with light. Here we show that the nonlinear polarizabilities of graphene
nanoislands can be electrically tuned to surpass by several orders of magnitude
those of metal nanoparticles of similar size. This extraordinary behavior
extends over the visible and near-infrared for islands consisting of hundreds
of carbon atoms doped with moderate carrier densities. Our quantum-mechanical
simulations of the plasmon-enhanced optical response of nanographene reveal
this material as an ideal platform for the development of electrically tunable
nonlinear optical nanodevices.Comment: 16 pages, 12 figures, 54 reference
Spatial scales of cirrus cloud properties
Research in studying the spatial scales of the cirrus, used data collected during the flight legs of the NCAR Sabreliner aircraft on four days during the FIRE Cirrus IFO to study the spatial scales of the cirrus, and will concentrate on the scales of horizontal wind. The spatial scales of the cloud features can be described by power spectra (or spectral density graphs) and cumulative variance graphs. The cumulative variance graphs were created by first using a Fast Fourier Transform (FFT) to create variance spectra. The variances were then summed in a cumulative fashion from the largest scalelengths (wavelengths) to the smallest. No detrending was done to the original data, and no smoothing or averaging was done to the spectral points. All the spectral points were included. This means that the values of the first five to ten spectral points of the large scalelengths should only be considered to be qualitatively correct. The cumulative variance at smaller scalelengths should be correct because a more accurate representation of the variance at the larger scalelengths should only redistribute the energy amongst the larger scalelengths
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