138,913 research outputs found
Carlson v. State and the Privileges and Immunities Clause: The Alaska Wrinkle in Nonresident Fishing Fee Differentials
Chromium ion plating studies for enhancement of bearing lifetime
Six 440-C hardened stainless steel roller bearing test rods were ion plated with various chromium films of thicknesses from .2 microns to 7 microns. The thinner (approximately .2 microns) coating sample had 3 times the fatigue life of the unplated (standard) specimens. Contrastingly, the samples having thicker coatings (several microns) had short fatigue lives (about 3% of the unplated standard)
The Past and Future of Light Dark Matter Direct Detection
We review the status and future of direct searches for light dark matter. We
start by answering the question: `Whatever happened to the light dark matter
anomalies?' i.e. the fate of the potential dark matter signals observed by the
CoGeNT, CRESST-II, CDMS-Si and DAMA/LIBRA experiments. We discuss how the
excess events in the first two of these experiments have been explained by
previously underestimated backgrounds. For DAMA we summarise the progress and
future of mundane explanations for the annual modulation reported in its event
rate. Concerning the future of direct detection we focus on the irreducible
background from solar neutrinos. We explain broadly how it will affect future
searches and summarise efforts to mitigate its effects.Comment: Invited review article for the International Journal of Modern
Physics A. 20 pages, 3 figure
A novel dry coal feeding concept for high-pressure gasifiers
A novel dry coal feeding concept was developed for injecting ground coal into high-pressure gasifiers. Significant power savings are projected because the coal is injected directly with a ram and there is no requirement for pumping large volumes of gas or fluid against pressure. A novel feature of the concept is that a new seal zone is formed between the ram and injection tube each cycle. The seal zone comprises a mixture of a small quantity of finely ground coal and a fluid. To demonstrate the feasibility of the concept, coal was injected into a 1000-psi chamber with an experimental device having a 7-1/2-inch-diameter ram and a 28-inch-long stroke
Commercial property prices and bank performance
We seek to assess the effect of changes in commercial property prices on bank behaviour
and performance in a range of industrialised economies, extending the existing micro literature on
bank performance. The results suggest that, consistent with macro-level studies, commercial property
prices have a marked impact on the behaviour and performance of individual banks. The signs found
are consistent with a view that commercial property provides important forms of collateral that are
perceived by banks to reduce risk and encourage lending. Such an impact exists even when
conventional independent variables determining bank performance are included. Moreover, there is
evidence that the magnitude of this impact is related to the size of the bank, the direction of
commercial property price movements, and regional factors. The results have implications for risk
managers, regulators and monetary policy makers. Notably, they underline the crucial relevance of
commercial property prices as a macroprudential variable that warrants close scrutiny by the
authorities. They also highlight the need to develop indicators of individual bank exposure to the
property market that could help to calibrate the potential impact of changes in prices in stress tests
Glow in the Dark Matter: Observing galactic halos with scattered light
We consider the observation of diffuse halos of light around the discs of
spiral galaxies, as a probe of the interaction cross section between Dark
Matter and photons. Using the galaxy M101 as an example, we show that for a
scattering cross section at the level of 10^(-23) x (m/GeV) cm^2 or greater
Dark Matter in the halo will scatter light out from the more luminous centre of
the disc to larger radii, contributing to an effective increased surface
brightness at the edges of the observed area on the sky. This allows us to set
an upper limit on the DM-photon cross section using data from the Dragonfly
instrument. We then show how to improve this constraint, and the potential for
discovery, by combining the radial profile of DM-photon scattering with
measurements at multiple wavelengths. Observation of diffuse light presents a
new and potentially powerful way to probe the interactions of Dark Matter with
photons, which is complimentary to existing searches.Comment: 6 pages, 3 figures: v2 matches version accepted to PRL, with an
extended discussion of potential background
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