18,508 research outputs found
Additions to fused-fluoride lubricant coatings for reduction of low-temperature friction
Additions to fused-fluoride lubricant coatings for reduction of low temperature frictio
Statics and Dynamics of Vortex Liquid Crystals
Using numerical simulations we examine the static and dynamic properties of
the recently proposed vortex liquid crystal state. We confirm the existence of
a smectic-A phase in the absence of pinning. Quenched disorder can induce a
smectic state even at T=0. When an external drive is applied, a variety of
anisotropic dynamical flow states with distinct voltage signatures occur,
including elastic depinning in the hard direction and plastic depinning in the
easy direction. We discuss the implications of the anisotropic transport for
other systems which exhibit depinning phenomena, such as stripes and electron
liquid crystals.Comment: 4 pages, 4 postscript figure
Pulsation of EE Cam
EE Cam is a previously little studied Delta Scuti pulsator with amplitudes
between those of the HADS (High-Amplitude Delta Scuti stars) group and the
average low-amplitude pulsators. Since the size of stellar rotation determines
both which pulsation modes are selected by the star as well as their
amplitudes, the star offers a great opportunity to examine the astrophysical
connections. Extensive photometric measurements covering several months were
carried out. 15 significant pulsation frequencies were extracted. The dominant
mode at 4.934 cd was identified as a radial mode by examining the phase
shifts at different wavelengths. Medium-dispersion spectra yielded a
value of km s. This shows that EE Cam belongs to the
important transition region between the HADS and normal Delta Scuti stars.Comment: 13 pages, 3 figures, 3 table
Spin-exchange Cross Sections For Hydrogen-atomalkali-metal-atom Collisions
The pseudopotential molecular-structure method has been used to calculate the X1 and a3 interaction potentials for the alkali-metal-atom hydrogen-atom systems. These potentials were then used in a quantum-mechanical calculation to determine the spin-exchange cross sections in the energy range from 2.5x10-4 eV to 2.5 eV. The cross sections follow the general form Q1/2=a-b lnv. However, abundant structure on the cross sections is present due to orbiting resonances induced by the deeply bound well of the X1 molecular state. The spin-exchange cross sections range from 17x10-16 to 25x10-16 cm2 at room temperature for H(F=1) transferring to H(F=0) in collision with unpolarized lithium and cesium, respectively. © 1985 The American Physical Society
CC267 Dairy Producer Waste Guidelines
Campaign Circular 267: This circular is about dairy producer waste guidelines
CC267 Dairy Producer Waste Guidelines
Campaign Circular 267: This circular is about dairy producer waste guidelines
Phase space analysis of two-wavelength interferometry
Multiple wavelength phase shifting interferometry is widely used to extend
the unambiguous range (UR) beyond that of a single wavelength. Towards this
end, many algorithms have been developed to calculate the optical path
difference (OPD) from the phase measurements of multiple wavelengths. These
algorithms fail when phase error exceeds a specific threshold. In this paper,
we examine this failure condition. We introduce a "phase-space" view of
multi-wavelength algorithms and demonstrate how this view may be used to
understand an algorithm's robustness to phase measurement error. In particular,
we show that the robustness of the synthetic wavelength algorithm deteriorates
near the edges of its UR. We show that the robustness of de Groot's extended
range algorithm [Appl. Opt. 33, 5948 (1994)] depends on both wavelength and OPD
in a non-trivial manner. Further, we demonstrate that the algorithm developed
by Houairi & Cassaing (HC) [J. Opt. Soc. Am. 26, 2503 (2009)] results in
uniform robustness across the entire UR. Finally, we explore the effect that
wavelength error has on the robustness of the HC algorithm.Comment: 8 pages, 7 figure
Molecular Treatment Of Charge Transfer In Li+ +Ca Collisions
The perturbed-stationary-state method, appended with electron translation factors, has been applied to charge transfer in Li+ +Ca collisions for energies from 0.1 to 20 keV/amu. The Born-Oppenheimer wave functions and eigenvalues were generated using the pseudopotential technique, which reduced the many-electron system to a simpler two-electron problem. The molecular ground-state X +1 is calculated to be bound and has the potential-well parameters Re=6.20a0, De=1.11 eV, e=235 cm-1, and Be=0.263 cm-1. From the scattering computations, a representative value for the charge-transfer cross section is 4x10-15 cm2 at 5 keV/amu. The cross section decreases rapidly as the energy is reduced below 1 keV/amu. At all energies studied, the dominant electron-capture reaction product is the ground-state Li atom. © 1983 The American Physical Society
Molecular-state Cross-section Calculations For H+CsH-+Cs+
Pseudopotential molecular-structure calculations have been used to obtain the seven lowest 1 and 1 states of CsH. These states and their associated radial and rotational coupling terms have been used to calculate the cross sections for H-+Cs+ ion-pair production in H+Cs(6s) and H+Cs*(6p) collisions at energies from 0.1 to 10 keV. The ion-ion mutual neutralization cross section, H-+Cs+ H+Cs, is also presented. The cross-section calculations were done with the perturbed-stationary-state method, modified to include two-electron translation factors. The ion-pair production cross section for ground-state reactants is in good agreement with experiment; collisions of H with excited Cs*(6p) show an order-of-magnitude enhancement of the ion-pair production cross section at 100 eV. The ion-ion mutual neutralization cross section is found to be large, attaining a value of 1.3 x 10-14 cm2 at 0.1 keV. © 1984 The American Physical Society
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