5,079 research outputs found
Polaron Transport in the Paramagnetic Phase of Electron-Doped Manganites
The electrical resistivity, Hall coefficient, and thermopower as functions of
temperature are reported for lightly electron-doped Ca(1-x)La(x)MnO(3)(0 <= x
<= 0.10). Unlike the case of hole-doped ferromagnetic manganites, the magnitude
and temperature dependence of the Hall mobility for these compounds is found to
be inconsistent with small-polaron theory. The transport data are better
described by the Feynman polaron theory and imply intermediate coupling (alpha
\~ 5.4) with a band effective mass, m*~4.3 m_0, and a polaron mass, m_p ~ 10
m_0.Comment: 7 pp., 7 Fig.s, to be published, PR
SETI science working group report
This report covers the initial activities and deliberations of a continuing working group asked to assist the SETI Program Office at NASA. Seven chapters present the group's consensus on objectives, strategies, and plans for instrumental R&D and for a microwave search for extraterrestrial in intelligence (SETI) projected for the end of this decade. Thirteen appendixes reflect the views of their individual authors. Included are discussions of the 8-million-channel spectrum analyzer architecture and the proof-of-concept device under development; signal detection, recognition, and identification on-line in the presence of noise and radio interference; the 1-10 GHz sky survey and the 1-3 GHz targeted search envisaged; and the mutual interests of SETI and radio astronomy. The report ends with a selective, annotated SETI reading list of pro and contra SETI publications
Effect of high-K dielectrics on charge transport in graphene
The effect of various dielectrics on charge mobility in single layer graphene
is investigated. By calculating the remote optical phonon scattering arising
from the polar substrates, and combining it with their effect on Coulombic
impurity scattering, a comprehensive picture of the effect of dielectrics on
charge transport in graphene emerges. It is found that though high-
dielectrics can strongly reduce Coulombic scattering by dielectric screening,
scattering from surface phonon modes arising from them wash out this advantage.
By comparing the room-temperature transport properties with narrow-bandgap
III-V semiconductors, strategies to improve the mobility in single layer
graphene are outlined.Comment: 6 pages, 4 Figure
Mapping API’s: Leaflet - Getting Started with Turf.js
Turf.js is an open source JavaScript library for advanced geospatial analysis that allows for spatial operations to be preformed in the browser. Turf will help you analyze, aggregate, and transform data in order to visualize it in new ways and answer spatial questions. This task sheet with get you getting started with Turf.js and demonstrate the midpoint measurement and linestring helper functions. You can find the completed code for this task sheet at https://github.com/ISUEOGTP/GISTaskSheets/tree/master/Leaflet-Tutorials/turf-midpoints.html.https://lib.dr.iastate.edu/gis_tasksheets/1002/thumbnail.jp
QGIS: Projections & Enabling on the Fly Projection
A projection is a way to translate the curved surface of the earth (3D) onto a flat map (2D). The challenge is that every map projection has distortion because the spherical nature of the globe cannot be perfectly represented in a two dimensional map. The picture below illustrates similarities and differences of three map projections. This image powerfully demonstrates the importance of defining the projection. For example, if you were working with data in Washington State you may have very different results working in Mercator or Lambert Conformal Conic. Knowing the projection of your data is important especially when working with data that is part of a dataset that is larger than just your county or state. This tasksheet will cover how to change the projection of an existing file as well as enabling on the fly projection in QGIS.https://lib.dr.iastate.edu/gis_tasksheets/1022/thumbnail.jp
Picosecond time-resolved pure-rotational coherent anti-Stokes Raman spectroscopy for N-2 thermometry
This paper was published in Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/abstract.cfm?URI=ol-34-23-3755. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.Peer reviewedPublisher PD
Connecting to Iowa Geographic Map Server Imagery: WMS Connection
Welcome to the Essential ArcGIS Task Sheet Series. This series supplements the Iowa State University GIS Geospatial Technology Training Program short course series, “Essential ArcGIS Tutorial Series.” The task sheets are designed to provide quick, easy instructions for performing specific tasks in GIS.https://lib.dr.iastate.edu/extension_pubs/1196/thumbnail.jp
Mapping API’s: Leaflet - GeoJSON Layer
Welcome to the Essential ArcGIS Task Sheet Series. This series supplements the Iowa State University GIS Geospatial Technology Training Program short course series. The task sheets are designed to provide quick, easy instructions for performing mapping taskshttps://lib.dr.iastate.edu/extension_pubs/1163/thumbnail.jp
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