2,211 research outputs found
Notes on lunar ilmenite
Opaques (mostly ilmenite) make up 0 to 5 percent of highland rocks, 1 to 11 percent of low-Ti mare basalts, and 10 to 34 percent of high-Ti mare basalts (Carter 1988). Apollos 11 and 17 sampled high-Ti basalts. Apollos 12 and 14 sampled low-Ti basalts. Apollo 15 sampled a complex mixture of mare and highland material. Apollo 16 sampled mainly highland material (Taylor 1975)
The Case against Mercury as the Angrite Parent Body (APB)
Angrites are not plausibly from Mercury based on their high FeO contents and ancient ages (e.g., [1]). Rather, the early crystallization ages of angrites argues for a small asteroidal-sized parent body for these meteorites (e.g., [2]). Despite this, recently it has been proposed that Mercury is the APB [3, 4, 5, 6]. Preserved corona and symplectite textures and the presence of 120 triple junctions in NWA 2999 have been cited as requiring a planetary origin [3, 4], with the symplectites in NWA 2999 resulting from rapid decompression during uplift via thrust faults on Mercury [4], and the coronas during subsequent cooling at low pressure. Glasses along grain boundaries and exsolution lamellae possibly indicative of rapid melting and cooling in NWA 4950 are cited as evidence of rapid decompression [6]. To explain the discrepancy between spectral observations of the Mercurian surface and the high FeO contents in angrites, an early (~4.5 Ga), collisionally-stripped FeO-rich basaltic surface has been suggested for Mercury [5, 6]
Math and the Mouse: Explorations of Mathematics and Science in Walt Disney World
Math and the Mouse is an intensive, collaborative, project-driven, study away course that runs during the three-week May Experience term at Furman University and has many of the attributes of a course-based undergraduate research experience in mathematics. We take twelve students to Orlando, Florida to study the behind-the-scenes mathematics employed to make Walt Disney World operate efficiently. Students learn techniques of mathematical modeling (mostly resource allocation, logistics, and scheduling models), statistical analysis (mostly probability, clustering, data collection, and hypothesis testing), and ow management (queuing theory and some beginning ow dynamics) in an applied setting. Through planned course modules, collaborative activities, conversations with guest speakers, and three group projects, one of which is of the students\u27 choosing, this academic experience provides an engaged learning experience that shows how material from eleven academic courses comes together in connection with real-world applications
Experiences of Older Adults Using Smart Home Technology in a Senior Living Community.
Researchers from a University partnered with a senior housing organization and a technology provider to study the implementation of smart home technologies for seniors living independently. Smart home technologies included in home motion and pressure sensors and an Amazon Echo device. Older adults who received the technology and their designated family members were interviewed to ascertain the impact of the technology on the daily activities and communication
Two-photon photoassociation spectroscopy of CsYb: Ground-state interaction potential and interspecies scattering lengths
We perform two-photon photoassociation spectroscopy of the heteronuclear CsYb molecule to measure the binding energies of near-threshold vibrational levels of the X 2+ 1/2 molecular ground state. We report results for 133Cs170Yb, 133Cs173Yb, and 133Cs174Yb, in each case determining the energy of several vibrational levels including the least-bound state. We fit an interaction potential based on electronic structure calculations to the binding energies for all three isotopologs and find that the ground-state potential supports 77 vibrational levels. We use the fitted potential to predict the interspecies s-wave scattering lengths for all seven Cs+Yb isotopic mixtures
Large Effects of Electric Fields on Atom-Molecule Collisions at Millikelvin Temperatures
Controlling interactions between cold molecules using external fields can
elucidate the role of quantum mechanics in molecular collisions. We create a
new experimental platform in which ultracold rubidium atoms and cold ammonia
molecules are separately trapped by magnetic and electric fields and then
combined to study collisions. We observe inelastic processes that are faster
than expected from earlier field-free calculations. We use quantum scattering
calculations to show that electric fields can have a major effect on collision
outcomes, even in the absence of dipole-dipole interactions.Comment: 5 pages, 4 figure
Interaction of surface acoustic waves with a two-dimensional electron gas in the presence of spin splitting of the Landau bands
The absorption and variation of the velocity of a surface acoustic wave of
frequency = 30 MHz interacting with two-dimensional electrons are
investigated in GaAs/AlGaAs heterostructures with an electron density at =1.5 - 4.2 K in magnetic fields up to 7 T.
Characteristic features associated with spin splitting of the Landau level are
observed. The effective g factor and the width of the spin-split Landau bands
are determined: and =0.6 meV. The greater width of the
orbital-split Landau bands (2 meV) relative to the spin-split bands is
attributed to different shielding of the random fluctuation potential of
charged impurities by 2D electrons. The mechanisms of the nonlinearities
manifested in the dependence of the absorption and the velocity increment of
the SAW on the SAW power in the presence of spin splitting of the Landau levels
are investigated.Comment: Revtex 5 pages + 5 EPS Figures, v.2 - minor corrections in text and
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Scalable stacked array piezoelectric deformable mirror for astronomy and laser processing applications
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