5,986 research outputs found
ERTS-1 image contributes to understanding of geologic structures related to Managua earthquake, 1972
ERTS-1 imaged the western portion of Nicaragua on December 24, 1972, one day after the central part of the city of Managua was devastated by a major earthquake which measured 5.6 on the Richter scale. ERTS-1 images reveal sets of lineaments (which may reflect fault systems) along any one of which movement could have taken place. One set includes a line of active volcanoes that parallels the coast and constitutes the southwestern edge of the Nicaraguan Depression, a regional graben which cuts obliquely across the Central American isthmus. This trend is offset approximately 10km in a right lateral geometric sense just west of the city of Managua. A parallel lineament, north of Lake Managua, marks the northeast edge of the graben. A second set, extends northward to northwestward from the mouth of the Rio Grande (Viejo) north of Lake Managua and can be projected southward across the lake to Managua. It is this set along which geometric offset of the volcanic lineament appears to have taken place
Maximizing nearest neighbour entanglement in finitely correlated qubit--chains
We consider translationally invariant states of an infinite one dimensional
chain of qubits or spin-1/2 particles. We maximize the entanglement shared by
nearest neighbours via a variational approach based on finitely correlated
states. We find an upper bound of nearest neighbour concurrence equal to
C=0.434095 which is 0.09% away from the bound C_W=0.434467 obtained by a
completely different procedure. The obtained state maximizing nearest neighbour
entanglement seems to approximate the maximally entangled mixed states (MEMS).
Further we investigate in detail several other properties of the so obtained
optimal state.Comment: 12 pages, 4 figures, 2nd version minor change
The Hudson Bay Lithospheric Experiment (HuBLE) : Insights into Precambrian Plate Tectonics and the Development of Mantle Keels
The UK component of HuBLE was supported by Natural Environment Research Council (NERC) grant NE/F007337/1, with financial and logistical support from the Geological Survey of Canada, Canada–Nunavut Geoscience Office, SEIS-UK (the seismic node of NERC), and First Nations communities of Nunavut. J. Beauchesne and J. Kendall provided invaluable assistance in the field. Discussions with M. St-Onge, T. Skulski, D. Corrigan and M. Sanborne-Barrie were helpful for interpretation of the data. D. Eaton and F. A. Darbyshire acknowledge the Natural Sciences and Engineering Research Council. Four stations on the Belcher Islands and northern Quebec were installed by the University of Western Ontario and funded through a grant to D. Eaton (UWO Academic Development Fund). I. Bastow is funded by the Leverhulme Trust. This is Natural Resources Canada Contribution 20130084 to its Geomapping for Energy and Minerals Program. This work has received funding from the European Research Council under the European Unions Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no. 240473 ‘CoMITAC’.Peer reviewedPublisher PD
The Rotation Period of the Planet-Hosting Star HD 189733
We present synoptic optical photometry of HD 189733, the chromospherically
active parent star of one of the most intensively studied exoplanets. We have
significantly extended the timespan of our previously reported observations and
refined the estimate of the stellar rotation period by more than an order of
magnitude: days. We derive a lower limit on the
inclination of the stellar rotation axis of 56\arcdeg (with 95% confidence),
corroborating earlier evidence that the stellar spin axis and planetary orbital
axis are well aligned.Comment: To appear in A
EFFECTS OF CARBON MONOXIDE ON DPG CONCENTRATIONS IN THE ERYTHROCYTE
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72782/1/j.1749-6632.1970.tb49791.x.pd
Status of SHAFT 78 with respect to modeling radioactive waste burial in Eleana argillite, including calculations to date
The SHAFT 78 Code (multidimensional, two fluid phases, porous medium) has been used to begin assessment of the consequences of nuclear waste burial in a 1000-acre repository emplaced in argillite. The methodology used can well be applied to other argillaceous rocks as well as to hard rocks in general so long as their in-situ rock permeability can reasonably be assumed to be temperature- and stress-independent. The repository is assumed to contain spent fuel (SF) UO{sub 2} at an initial power loading of 150 kW/acre and located at a depth of 600 m. It was found that with perfect backfill (permeabilty = 1 x 10{sup 7} darcy), a maximum fluid pressure of 770 bars existed in the repository at a time of 55 y after burial. Holding all other input variables constant, the maximum fluid pressure in the repository never exceeded the local lithostatic pressure when the permeability of the backfill material was increased to 1 x 10{sup -1} darcy. The calculated temperature histories are essentially independent of backfill permeability and porosity, indicating that heat transfer is conduction-dominated
Postfledging Survival, Movements, and Dispersal of Ring Ouzels (Turdus torquatus)
We thank Invercauld Estate for cooperation with access to Glen Clunie. S. Redpath, J. Wilson, and S. Roos provided valuable comments on the manuscript. This study was funded by the Royal Society for the Protection of Birds, Scottish Natural Heritage, and the Cairngorms National Park Authority. J.L.L. was supported by the Natural Environment Research Council.Peer reviewedPublisher PD
A One-Dimensional Volcanic Plume Model for Predicting Ash Aggregation
During explosive volcanic eruptions, volcanic ash is ejected into the atmosphere, impacting aircraft safety and downwind communities. These volcanic clouds tend to be dominated by fine ash (μm in diameter), permitting transport over hundreds to thousands of kilometers. However, field observations show that much of this fine ash aggregates into clusters or pellets with faster settling velocities than individual particles. Models of ash transport and deposition require an understanding of aggregation processes, which depend on factors like moisture content and local particle collision rates. In this study, we develop a Plume Model for Aggregate Prediction, a one-dimensional (1D) volcanic plume model that predicts the plume rise height, concentration of water phases, and size distribution of resulting ash aggregates from a set of eruption source parameters. The plume model uses a control volume approach to solve mass, momentum, and energy equations along the direction of the plume axis. The aggregation equation is solved using a fixed pivot technique and incorporates a sticking efficiency model developed from analog laboratory experiments of particle aggregation within a novel turbulence tower. When applied to the 2009 eruption of Redoubt Volcano, Alaska, the 1D model predicts that the majority of the plume is over-saturated with water, leading to a high rate of aggregation. Although the mean grain size of the computed Redoubt aggregates is larger than the measured deposits, with a peak at 1 mm rather than 500 μm, the present results provide a quantitative estimate for the magnitude of aggregation in an eruption
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