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Dynamic wetting for continuum hydrodynamics with multi-component Lattice Boltzmann equation simulation method
This paper was presented at the 2nd Micro and Nano Flows Conference (MNF2009), which was held at Brunel University, West London, UK. The conference was organised by Brunel University and supported by the Institution of Mechanical Engineers, IPEM, the Italian Union of Thermofluid dynamics, the Process Intensification Network, HEXAG - the Heat Exchange Action Group and the Institute of Mathematics and its Applications.We present methodological innovations to the multi-component lattice Boltzmann equation
simulation method which allow for the simulation of dynamic contact lines in the continuum approximation. The improvements are set-out and verified by quantitative results. They allow the simulator access to an expanded range of simulation parameters like viscosity, viscosity contrast and interfacial tensions, and to obtain data with low levels of interfacial micro-current activity in the region of the dynamic contact line
Detection of Voigt Spectral Line Profiles of Hydrogen Radio Recombination Lines toward Sagittarius B2(N)
We report the detection of Voigt spectral line profiles of radio
recombination lines (RRLs) toward Sagittarius B2(N) with the 100-m Green Bank
Telescope (GBT). At radio wavelengths, astronomical spectra are highly
populated with RRLs, which serve as ideal probes of the physical conditions in
molecular cloud complexes. An analysis of the Hn(alpha) lines presented herein
shows that RRLs of higher principal quantum number (n>90) are generally
divergent from their expected Gaussian profiles and, moreover, are well
described by their respective Voigt profiles. This is in agreement with the
theory that spectral lines experience pressure broadening as a result of
electron collisions at lower radio frequencies. Given the inherent technical
difficulties regarding the detection and profiling of true RRL wing spans and
shapes, it is crucial that the observing instrumentation produce flat baselines
as well as high sensitivity, high resolution data. The GBT has demonstrated its
capabilities regarding all of these aspects, and we believe that future
observations of RRL emission via the GBT will be crucial towards advancing our
knowledge of the larger-scale extended structures of ionized gas in the
interstellar medium (ISM)
The Spatial Distribution of Complex Organic Molecules in the L1544 Pre-stellar Core.
journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05journal_title: The Astrophysical Journal article_type: paper article_title: THE SPATIAL DISTRIBUTION OF COMPLEX ORGANIC MOLECULES IN THE L1544 PRE-STELLAR CORE copyright_information: © 2016. The American Astronomical Society. All rights reserved. date_received: 2016-05-27 date_accepted: 2016-09-12 date_epub: 2016-10-05The detection of complex organic molecules (COMs) toward cold sources such as pre-stellar cores (with T<10 K), has challenged our understanding of the formation processes of COMs in the interstellar medium. Recent modelling on COM chemistry at low temperatures has provided new insight into these processes predicting that COM formation depends strongly on parameters such as visual extinction and the level of CO freeze out. We report deep observations of COMs toward two positions in the L1544 pre-stellar core: the dense, highly-extinguished continuum peak with A V ≥30 mag within the inner 2700 au; and a low-density shell with average A V ~7.5-8 mag located at 4000 au from the core's center and bright in CH3OH. Our observations show that CH3O, CH3OCH3 and CH3CHO are more abundant (by factors ~2-10) toward the low-density shell than toward the continuum peak. Other COMs such as CH3OCHO, c-C3H2O, HCCCHO, CH2CHCN and HCCNC show slight enhancements (by factors ≤3) but the associated uncertainties are large. This suggests that COMs are actively formed and already present in the low-density shells of pre-stellar cores. The modelling of the chemistry of O-bearing COMs in L1544 indicates that these species are enhanced in this shell because i) CO starts freezing out onto dust grains driving an active surface chemistry; ii) the visual extinction is sufficiently high to prevent the UV photo-dissociation of COMs by the external interstellar radiation field; and iii) the density is still moderate to prevent severe depletion of COMs onto grains
The effects of dolomitization on petrophysical properties and fracture distribution within rift-related carbonates (Hammam Faraun Fault Block, Suez Rift, Egypt)
Full custom design of an arbitrary waveform gate driver with 10 GHz waypoint rates for GaN FETs
THE GOLDEN YEARS OF EASTERN OREGON
P. miion is granted to reprint infonl'lCllion c:onfolned h.. ein. An
Global existence for semilinear reaction-diffusion systems on evolving domains
We present global existence results for solutions of reaction-diffusion
systems on evolving domains. Global existence results for a class of
reaction-diffusion systems on fixed domains are extended to the same systems
posed on spatially linear isotropically evolving domains. The results hold
without any assumptions on the sign of the growth rate. The analysis is valid
for many systems that commonly arise in the theory of pattern formation. We
present numerical results illustrating our theoretical findings.Comment: 24 pages, 3 figure
The Ultraviolet Imaging Telescope: Instrument and Data Characteristics
The Ultraviolet Imaging Telescope (UIT) was flown as part of the Astro
observatory on the Space Shuttle Columbia in December 1990 and again on the
Space Shuttle Endeavor in March 1995. Ultraviolet (1200-3300 Angstroms) images
of a variety of astronomical objects, with a 40 arcmin field of view and a
resolution of about 3 arcsec, were recorded on photographic film. The data
recorded during the first flight are available to the astronomical community
through the National Space Science Data Center (NSSDC); the data recorded
during the second flight will soon be available as well. This paper discusses
in detail the design, operation, data reduction, and calibration of UIT,
providing the user of the data with information for understanding and using the
data. It also provides guidelines for analyzing other astronomical imagery made
with image intensifiers and photographic film.Comment: 44 pages, LaTeX, AAS preprint style and EPSF macros, accepted by PAS
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