5,560 research outputs found
Engineering properties of potassium tenth quarterly report, jan. 1 - mar. 31, 1963
Thermodynamic and transport properties of potassium in temperature range 900 to 2100 deg
Engineering properties of potassium and cesium thirteenth quarterly report, 1 oct. - 31 dec. 1963
Thermal conductivity of potassium vapo
Engineering properties of potassium and cesium twelfth quarterly report, 1 jul. - 30 sep. 1963
Physical and chemical properties of cesium and potassiu
Coordinate systems for differential correction
System of state transition partial derivatives for which tracking information normal matrix for lunar orbiter is nearly diagonalize
Pleckstrin Homology Domains: Two Halves Make a Hole?
In a recent issue of Nature, van Rossum et al. report binding of a “split” pleckstrin homology (PH) domain from phospholipase C-γ1 to the TRPC3 ion channel. Through sequence analyses and in vitro studies, they suggest a novel mode of protein-protein interaction in which two PH domain fragments in distinct proteins associate to form an “intermolecular” PH domain that binds inositol phospholipids and is required for ion channel location and function
Dimensionless scaling of heat-release-induced planar shock waves in near-critical CO2
We performed highly resolved one-dimensional fully compressible Navier-Stokes
simulations of heat-release-induced compression waves in near-critical CO2. The
computational setup, inspired by the experimental setup of Miura et al., Phys.
Rev. E, 2006, is composed of a closed inviscid (one-dimensional) duct with
adiabatic hard ends filled with CO2 at three supercritical pressures. The
corresponding initial temperature values are taken along the pseudo-boiling
line. Thermodynamic and transport properties of CO2 in near-critical conditions
are modeled via the Peng-Robinson equation of state and Chung's Method. A heat
source is applied at a distance from one end, with heat release intensities
spanning the range 10^3-10^11 W/m^2, generating isentropic compression waves
for values < 10^9 W/m^2. For higher heat-release rates such compressions are
coalescent with distinct shock-like features (e.g. non-isentropicity and
propagation Mach numbers measurably greater than unity) and a non-uniform
post-shock state is present due to the strong thermodynamic nonlinearities. The
resulting compression wave intensities have been collapsed via the thermal
expansion coefficient, highly variable in near-critical fluids, used as one of
the scaling parameters for the reference energy. The proposed scaling applies
to isentropic thermoacoustic waves as well as shock waves up to shock strength
2. Long-term time integration reveals resonance behavior of the compression
waves, raising the mean pressure and temperature at every resonance cycle. When
the heat injection is halted, expansion waves are generated, which counteract
the compression waves leaving conduction as the only thermal relaxation
process. In the long term evolution, the decay in amplitude of the resonating
waves observed in the experiments is qualitatively reproduced by using
isothermal boundary conditions.Comment: As submitted to AIAA SciTech 2017, available at
http://arc.aiaa.org/doi/pdf/10.2514/6.2017-008
Cell Signaling by Receptor Tyrosine Kinases
Recent structural studies of receptor tyrosine kinases (RTKs) have revealed unexpected diversity in the mechanisms of their activation by growth factor ligands. Strategies for inducing dimerization by ligand binding are surprisingly diverse, as are mechanisms that couple this event to activation of the intracellular tyrosine kinase domains. As our understanding of these details becomes increasingly sophisticated, it provides an important context for therapeutically countering the effects of pathogenic RTK mutations in cancer and other diseases. Much remains to be learned, however, about the complex signaling networks downstream from RTKs and how alterations in these networks are translated into cellular responses
Alternative derivation of the relativistic contribution to perihelic precession
An alternative derivation of the first-order relativistic contribution to
perihelic precession is presented. Orbital motion in the Schwarzschild geometry
is considered in the Keplerian limit, and the orbit equation is derived for
approximately elliptical motion. The method of solution makes use of coordinate
transformations and the correspondence principle, rather than the standard
perturbative approach. The form of the resulting orbit equation is similar to
that derived from Newtonian mechanics and includes first-order corrections to
Kepler's orbits due to general relativity. The associated relativistic
contribution to perihelic precession agrees with established first-order
results. The reduced radius for the circular orbit is in agreement to
first-order with that calculated from the Schwarzschild effective potential.
The method of solution is understandable by undergraduate students.Comment: 12 pages, 2 figures. Accepted for publication in the American Journal
of Physic
Probing the hydrogen melting line at high pressures by dynamic compression
We investigate the capabilities of dynamic compression by intense heavy ion beams to yield information about the high pressure phases of hydrogen. Employing ab initio simulations and experimental data, a new wide range equation of state for hydrogen is constructed. The results show that the melting line up to its maximum as well as the transition from molecular fluids to fully ionized plasmas can be tested with the beam parameters soon to be available. We demonstrate that x-ray scattering can distinguish between phases and dissociation states
Flow probe of symmetry energy in relativistic heavy-ion reactions
Flow observables in heavy-ion reactions at incident energies up to about 1
GeV per nucleon have been shown to be very useful for investigating the
reaction dynamics and for determining the parameters of reaction models based
on transport theory. In particular, the elliptic flow in collisions of
neutron-rich heavy-ion systems emerges as an observable sensitive to the
strength of the symmetry energy at supra-saturation densities. The comparison
of ratios or differences of neutron and proton flows or neutron and hydrogen
flows with predictions of transport models favors an approximately linear
density dependence, consistent with ab-initio nuclear-matter theories.
Extensive parameter searches have shown that the model dependence is comparable
to the uncertainties of existing experimental data. Comprehensive new flow data
of high accuracy, partly also through providing stronger constraints on model
parameters, can thus be expected to improve our knowledge of the equation of
state of asymmetric nuclear matter.Comment: 20 pages, 24 figures, review to appear in EPJA special volume on
nuclear symmetry energ
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