2,009 research outputs found
Correspondence M. Rebecca Boggs, March 18, 1903 - December 2, 1911
Correspondence M. Rebecca Boggs, March 18, 1903 - December 2, 1911.
Box 2, folder 8.https://digitalcommons.wofford.edu/littlejohnboggs/1018/thumbnail.jp
A direct urea fuel cell - power from fertiliser and waste
For the first time, a working direct urea and direct urine fuel cell has been developed to generate electricity directly from urea or urine
Google Earth® Models with COLLADA and WxAzygy® Transparent Interface: An example from Grotto Creek, Front Ranges, Canadian Cordillera
Virtual globes represent a paradigm shift for geoscience education. It is now possible to explore real world experiences across the entire Earth, the Moon, and Mars, and also to combine multiple 2-D images into one 3-D image with topography. Models viewed in Google Earth® are more intuitive for visualizing 3-D geological structures than traditional paper maps and cross-sections. Here a student-constructed geological map and cross-sections from an introductory field school are used to illustrate the creation of a draped geological map over topography. A custom vertical slider elevates the cross-sections above topography and a horizontal slider restores thrust faulting. Models located in situ in topography are made queryable via a ‘cut-away’ using the WxAzygy® transparent interface.SOMMAIRE La notion de « globes virtuels » constitue un changement de paradigme dans le domaine de l’éducation en géoscience. Il est maintenant possible de traiter de la réalité de tous les recoins de la Terre, de la lune et de Mars, et aussi de combiner de multiples images 2-D en une image 3-D affichant la topographie. Les modèles de Google Earth® permettent une visualisation 3-D plus intuitive des structures géologiques que ne le permettent les cartes papiers usuelles et les coupes. Dans la présente, une carte géologique et une coupe réalisées par un étudiant d’un cours d’introduction au travail de terrain sont utilisées pour illustrer la confection d’une carte géologique appliquée sur la topographie correspondante. Un curseur vertical personnalisé dessine les coupes au-dessus de la topographie, et un curseur horizontal permet de restaurer les failles de chevauchement. Ces modèles ancrés au droit de la topographie peuvent être exploiter au moyen d’un écorché produit par l’interface transparent WxAzygy®
Ambiguity of gamma-ray tracking of "two-interaction" events
Tracking of gamma-ray interactions in germanium detectors can allow
reconstruction of the photon paths, and is useful for many applications.
Scrutiny of the kinematics and geometry of gamma rays which are Compton
scattered only once prior to full absorption reveals that there are cases where
even perfect spatial and energy resolution cannot resolve the true interaction
sequence and consequently gamma-ray tracks cannot be reconstructed. The photon
energy range where this ambiguity exists is from 255 keV to around 700 keV.
This is a region of importance for nuclear structure research where two-point
interactions are probable.Comment: 8 pages, 2 figure
Modeling kicks from the merger of generic black-hole binaries
Recent numerical relativistic results demonstrate that the merger of
comparable-mass spinning black holes has a maximum ``recoil kick'' of up to
\sim 4000 \kms. However the scaling of these recoil velocities with mass
ratio is poorly understood. We present new runs showing that the maximum
possible kick perpendicular to the orbital plane does not scale as
(where is the symmetric mass ratio), as previously proposed, but is more
consistent with , at least for systems with low orbital precession.
We discuss the effect of this dependence on galactic ejection scenarios and
retention of intermediate-mass black holes in globular clusters.Comment: 5 pages, 1 figure, 3 tables. Version published in Astrophys. J. Let
Land, family and Hawaiian resistance
Contents were included in anthropology course on Peoples of Hawai'i taught beginning in 1971"A Nation Rising: A review" added as an addendum. July 28, 2015.The book takes the form of an extended essay, quoting facts and figures, the words of individuals, and observations of behavior recorded for
the most part during the 1970's and '80's. It contains what individual Hawaiians at particular times and in particular circumstances have shared with me, as understood by me. I emphasize that many Hawaiians would have views and experiences which differ from those cited herein. The connections I see are, like all such, arguable. I may have gotten it wrong. If so, someone hopefully will correct me. But in any case, it is my essay. I do not claim that it represents the views of all Hawaiians; only those quoted herein and subject to the limitations mentioned
Diffuse Galactic Soft Gamma-Ray Emission
The Galactic diffuse soft gamma-ray (30-800 keV) emission has been measured
from the Galactic Center by the HIREGS balloon-borne germanium spectrometer to
determine the spectral characteristics and origin of the emission. The
resulting Galactic diffuse continuum is found to agree well with a single
power-law (plus positronium) over the entire energy range, consistent with RXTE
and COMPTEL/CGRO observations at lower and higher energies, respectively. We
find no evidence of spectral steepening below 200 keV, as has been reported in
previous observations. The spatial distribution along the Galactic ridge is
found to be nearly flat, with upper limits set on the longitudinal gradient,
and with no evidence of an edge in the observed region. The soft gamma-ray
diffuse spectrum is well modeled by inverse Compton scattering of interstellar
radiation off of cosmic-ray electrons, minimizing the need to invoke
inefficient nonthermal bremsstrahlung emission. The resulting power requirement
is well within that provided by Galactic supernovae. We speculate that the
measured spectrum provides the first direct constraints on the cosmic-ray
electron spectrum below 300 MeV.Comment: 26 pages, 7 figure, submitted to Ap
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