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Research Factsheet: Woodfuel experiment - North Thurlbar, Newton Rigg
An experiment has been set up to assess the economic viability and environmental impacts of woodfuel harvesting in North Thurlbar, a small wood land on the University of Cumbria Newton Rigg campus estate. This factsheet describes the aim of the study and the experiment design
Testing Extended Technicolor With
We review the connection between and the vertex in ETC
models and demonstrate the power of the resulting experimental constraint on
models with weak-singlet ETC bosons. Some efforts to bring ETC models into
agreement with experimental data on the vertex are mentioned, and
the most promising one (non-commuting ETC) is discussed in detail.Comment: Talk given by E.H. Simmons at the Yukawa International Seminar `95 in
Kyoto, 21-26 August, 1995 and at the International Symposium on Heavy Flavor
and Electroweak Theory in Beijing, 17-19 August, 1995. Latex (uses PTPTeX.sty
and epsf). 9 pages. 1 figure. Full postscript version available at
http://smyrd.bu.edu/ . (minor typos corrected
Energy storage-boiler tank
Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed
Cast iron-base alloy for cylinder/regenerator housing
NASACC-1 is a castable iron-base alloy designed to replace the costly and strategic cobalt-base X-40 alloy used in the automotive Stirling engine cylinder/generator housing. Over 40 alloy compositions were evaluated using investment cast test bars for stress-rupture testing. Also, hydrogen compatibility and oxygen corrosion resistance tests were used to determine the optimal alloy. NASACC-1 alloy was characterized using elevated and room temperature tensile, creep-rupture, low cycle fatigue, heat capacity, specific heat, and thermal expansion testing. Furthermore, phase analysis was performed on samples with several heat treated conditions. The properties are very encouraging. NASACC-1 alloy shows stress-rupture and low cycle fatigue properties equivalent to X-40. The oxidation resistance surpassed the program goal while maintaining acceptable resistance to hydrogen exposure. The welding, brazing, and casting characteristics are excellent. Finally, the cost of NASACC-1 is significantly lower than that of X-40
Placing Confidence Limits on Polarization Measurements
The determination of the true source polarization given a set of measurements
is complicated by the requirement that the polarization always be positive.
This positive bias also hinders construction of upper limits, uncertainties,
and confidence regions, especially at low signal-to-noise levels. We generate
the likelihood function for linear polarization measurements and use it to
create confidence regions and upper limits. This is accomplished by integrating
the likelihood function over the true polarization (parameter space), rather
than the measured polarization (data space). These regions are valid for both
low and high signal-to-noise measurements.Comment: 8 pages, 3 figures, 1 table, submitted to PAS
Higgsless Models: Lessons from Deconstruction
This talk reviews recent progress in Higgsless models of electroweak symmetry
breaking, and summarizes relevant points of model-building and phenomenology.Comment: 12 pages, 2 figures, Presented at the X Mexican Workshop on Particles
and Field
Group Analysis of Self-organizing Maps based on Functional MRI using Restricted Frechet Means
Studies of functional MRI data are increasingly concerned with the estimation
of differences in spatio-temporal networks across groups of subjects or
experimental conditions. Unsupervised clustering and independent component
analysis (ICA) have been used to identify such spatio-temporal networks. While
these approaches have been useful for estimating these networks at the
subject-level, comparisons over groups or experimental conditions require
further methodological development. In this paper, we tackle this problem by
showing how self-organizing maps (SOMs) can be compared within a Frechean
inferential framework. Here, we summarize the mean SOM in each group as a
Frechet mean with respect to a metric on the space of SOMs. We consider the use
of different metrics, and introduce two extensions of the classical sum of
minimum distance (SMD) between two SOMs, which take into account the
spatio-temporal pattern of the fMRI data. The validity of these methods is
illustrated on synthetic data. Through these simulations, we show that the
three metrics of interest behave as expected, in the sense that the ones
capturing temporal, spatial and spatio-temporal aspects of the SOMs are more
likely to reach significance under simulated scenarios characterized by
temporal, spatial and spatio-temporal differences, respectively. In addition, a
re-analysis of a classical experiment on visually-triggered emotions
demonstrates the usefulness of this methodology. In this study, the
multivariate functional patterns typical of the subjects exposed to pleasant
and unpleasant stimuli are found to be more similar than the ones of the
subjects exposed to emotionally neutral stimuli. Taken together, these results
indicate that our proposed methods can cast new light on existing data by
adopting a global analytical perspective on functional MRI paradigms.Comment: 23 pages, 5 figures, 4 tables. Submitted to Neuroimag
Influence of chopped laser light onto the electronic transport through atomic-sized contacts
This article reports on the influence of laser irradiation onto the
electrical conductance of gold nanocontacts established with the mechanically
controllable breakjunction technique (MCB). We concentrate here on the study of
reversible conductance changes which can be as high as 200%. We investigate the
dependence on the initial conductance of the contacts, the wavelength, the
intensity and position of the laser spot with respect to the sample. Under most
conditions an enhancement of the conductance is observed. We discuss several
physical mechanisms which might contribute to the observed effect including
thermal expansion, rectification and photon-assisted transport. We conclude
that thermal expansion is not the dominating one.Comment: 20 pages with 7 figures; conference contribution on the 9th near
field optics conference 2006 in Lausanne, Switzerland; accepted by the
Journal of Microscop
Facile Protocol for Water-Tolerant “Frustrated Lewis Pair”-Catalyzed Hydrogenation
Despite rapid advances in the field of metal-free, “frustrated Lewis pair” (FLP)-catalyzed hydrogenation, the need for strictly anhydrous reaction conditions has hampered wide-scale uptake of this methodology. Herein, we report that, despite the generally perceived moisture sensitivity of FLPs, 1,4-dioxane solutions of B(C6F5)3 actually show appreciable moisture tolerance and can catalyze hydrogenation of a range of weakly basic substrates without the need for rigorously inert conditions. In particular, reactions can be performed directly in commercially available nonanhydrous solvents without subsequent drying or use of internal desiccants
Similarities and contrasts in tectonic and volcanic style and history along the Colorado plateaus-to-basin and range transition zone in Western Arizona: Geologic framework for tertiary extensional tectonics
The overall temporal and spatial relations between middle Tertiary volcanism and tectonism from the Basin and Range province onto the edge of the Colorado Plateaus province suggest that a single magnetic-tectonic episode affected the entire region more or less simultaneously during this period. The episode followed a post-Laramide (late Eocene through Oligocene) period of 25 million years of relative stability. Middle Tertiary volcanism did not migrate gradually eastward in a simple fashion onto the Colorado Plateau. In fact, late Oligocene volcanism appears to be more voluminous near the Aquarius Mountains than throughout the adjacent Basin and Range province westward to the Colorado River. Any model proposed to explain the cause of extension and detachment faulting in the eastern part of the Basin and Range province must consider that the onset of volcanism appears to have been approximately synchronous from the Colorado River region of the Basin and Range across the transition zone and onto the edge of the Colorado Plateaus
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