75,238 research outputs found
Spin transport in coupled spinor Bose gases
We report direct measurements of spin transport in a trapped, partially
condensed spinor Bose gas. Detailed analyses of spin flux in this
out-of-equilibrium quantum gas are performed by monitoring the flow of atoms in
different hyperfine spin states. The main mechanisms for motion in this system
are exchange scattering and potential energy inhomogeneity, which lead to spin
waves in the normal component and domain formation in the condensate. We find a
large discrepancy in domain formation timescales with those predicted by
potential-driven formation, indicating strong coupling of the condensate to the
normal component spin wave
Learning theory and its application to female learner support in engineering
School of Engineering at Murdoch University is now in its fifth year: a new School sited on the new regional Campus. This environment enabled the staff to take an innovative approach to the School's development. One key issue addressed from the outset was that of women in a nontraditional area.
Positive action was taken to attract high calibre female staff and as a consequence over 50% of the School's staff, academic and non-academic, are female. From the student perspective, issues confronting females studying in Engineering, which are reflected in international low recruitment and retention, continue to be addressed.
Individuals are different and these differences affect how a student performs. In particular, gender differences in learning styles have been noted. This has directed us to administer, as part of a first year foundational unit, learning style inventories to all first year students, who then identify their self-reported learning styles.
In this positive atmosphere many varied and successful initiatives, based on our learning style research, are being trialled to encourage female students into our programs and then support and retain them throughout their four years of study.
This research discusses the initial learning style results and their application to our initiatives
Recovering a Lost Story Using Oral History: The United States Supreme Court\u27s Historic Green v. New Kent County, Virginia, Decision
In 1965, New Kent County, located just east of Richmond, Virginia, became the setting for the one of the most important school desegregation cases since Brown v. Board of Education. Ten years after the U.S. Supreme Court declared separate but equal unconstitutional, both public schools in New Kent, the George W. Watkins School for blacks and the New Kent School for whites, remained segregated. In 1965, however, local blacks and the Virginia State NAACP initiated a legal challenge to segregated schools, hoping to initiate desegregation where the process had yet to begin and to accelerate the process in areas where token desegregation was the norm. In 1968, the U.S. Supreme Court decision inCharles C. Green v. the School Board of New Kent County forced New Kent County and localities across the state and nation to fulfill the promise of Brown. While the case has been part of the court records since it was decided in 1968, it has remained largely unknown to the general public and many scholars of the era. This article is an attempt to use the tool of oral history to present the people and the story behind Green v. New Kent County and to add another piece to the puzzle that was school desegregation in this country
Hole polaron formation and migration in olivine phosphate materials
By combining first principles calculations and experimental XPS measurements,
we investigate the electronic structure of potential Li-ion battery cathode
materials LiMPO4 (M=Mn,Fe,Co,Ni) to uncover the underlying mechanisms that
determine small hole polaron formation and migration. We show that small hole
polaron formation depends on features in the electronic structure near the
valence-band maximum and that, calculationally, these features depend on the
methodology chosen for dealing with the correlated nature of the
transition-metal d-derived states in these systems. Comparison with experiment
reveals that a hybrid functional approach is superior to GGA+U in correctly
reproducing the XPS spectra. Using this approach we find that LiNiPO4 cannot
support small hole polarons, but that the other three compounds can. The
migration barrier is determined mainly by the strong or weak bonding nature of
the states at the top of the valence band, resulting in a substantially higher
barrier for LiMnPO4 than for LiCoPO4 or LiFePO4
Effect of phonon-phonon interactions on localization
We study the heat current J in a classical one-dimensional disordered chain
with on-site pinning and with ends connected to stochastic thermal reservoirs
at different temperatures. In the absence of anharmonicity all modes are
localized and there is a gap in the spectrum. Consequently J decays
exponentially with system size N. Using simulations we find that even a small
amount of anharmonicity leads to a J~1/N dependence, implying diffusive
transport of energy.Comment: 4 pages, 2 figures, Published versio
Gravity enhanced acoustic levitation method and apparatus
An acoustic levitation system is provided for acoustically levitating an object by applying a single frequency from a transducer into a resonant chamber surrounding the object. The chamber includes a stabilizer location along its height, where the side walls of the chamber are angled so they converge in an upward direction. When an acoustic standing wave pattern is applied between the top and bottom of the chamber, a levitation surface within the stabilizer does not lie on a horizontal plane, but instead is curved with a lowermost portion near the vertical axis of the chamber. As a result, an acoustically levitated object is urged by gravity towards the lowermost location on the levitation surface, so the object is kept away from the side walls of the chamber
Transition metal impurities in semiconductors
Crystal field theory applied transition metal impurities in semiconductor
Local field effect as a function of pulse duration
In this note we give semiclassical consideration of the role of pulse
duration in observation of local field effects in the regime of optical
switching. We show that the main parameter governing local field influence is
the ratio of peak Rabi frequency corresponding to medium inversion and Lorentz
frequency of the medium. To obtain significant local field effect, this
parameter should be near unity that is valid only for long enough pulses. We
also discuss the role of relaxation and pulse shape in this processes.Comment: 4 pages, 3 figure
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