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TEM Studies of Carbon Coated LiFePO4 after Charge DischargeCycling

Description: Carbon coating has proven to be a successful approach toimprove the rate capability of LiFePO4 used in rechargeable Li-ionbatteries. Investigations of the microstructure of carbon coated LiFePO4after charge discharge cycling shows that the carbon surface layerremains intact over 100 cycles. We find micro cracks in the cycledmaterial that extend parallel to low indexed lattice planes. Ourobservations differ from observations made by other authors. However thedifferences between the orientations … more
Date: November 30, 2006
Creator: Gabrisch, H.; Wilcox, J. & Doeff, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A SURFACE CRYSTALLOGRAPHY STUDY BY DYNAMICAL LEED OF THE (sqrt3xsqrt3)R30o CO STRUCTURE ON THE Rh(111) CRYSTAL SURFACE

Description: The atomic positions of the Rh(111) + ({radical}3 x {radical}3)R30{sup o} CO and CO{sub 2} surfaces are analyzed by dynamical LEED. The Rh(111) + ({radical}3 x {radical}3)R30{sup o} CO and CO{sub 2} systems produce identical I-V curves, confirming the dissociation of CO{sub 2} to CO on this surface. The adsorbed CO is found to stand perpendicular to the surface with the carbon end down at an atop site (that is, terminally bonded). The CO overlayer spacings are d{sub RhC} = 1.95 {+-} 0.1 {angstr… more
Date: September 1, 1980
Creator: Koestner, R.J.; Van Hove, M.A. & Somorjai, G.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Predictions of Elliptic flow and nuclear modification factor from 200 GeV U+U collisions at RHIC

Description: Predictions of elliptic flow (v{sub 2}) and nuclear modification factor (R{sub AA}) are provided as a function of centrality in U + U collisions at {radical}s{sub NN} = 200 GeV. Since the {sup 238}U nucleus is naturally deformed, one could adjust the properties of the fireball, density and duration of the hot and dense system, for example, in high energy nuclear collisions by carefully selecting the colliding geometry. Within our Monte Carlo Glauber based approach, the v{sub 2} with respect to … more
Date: July 7, 2010
Creator: Masui, Hiroshi; Mohanty, Bedangadas & Xu, Nu
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Designing the Ideal Uranyl Ligand: a Sterically-Induced Speciation Change in Complexes with Thiophene-Bridged Bis(3-hydroxy-N-methylpyridin-2-one)

Description: Structural characterization of a mononuclear uranyl complex with a tetradentate, thiophene-linked bis(3-hydroxy-N-methylpyridin-2-one) ligand reveals the most planar coordination geometry yet observed with this ligand class. The introduction of ethylsulfanyl groups onto the thiophene linker disrupts this planar, conjugated ligand arrangement, resulting in the formation of dimeric (UO{sub 2}){sub 2}L{sub 2} species in which each ligand spans two uranyl centers. Relative energy calculations revea… more
Date: September 11, 2009
Creator: Szigethy, Geza & Raymond, Kenneth N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Loops in Reeb Graphs of 2-Manifolds

Description: Given a Morse function f over a 2-manifold with or without boundary, the Reeb graph is obtained by contracting the connected components of the level sets to points. We prove tight upper and lower bounds on the number of loops in the Reeb graph that depend on the genus, the number of boundary components, and whether or not the 2-manifold is orientable. We also give an algorithm that constructs the Reeb graph in time O(n log n), where n is the number of edges in the triangulation used to represen… more
Date: February 11, 2003
Creator: Cole-McLaughlin, K; Edelsbrunner, H; Harer, J; Natarajan, V & Pascucci, V
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Program on the IBM 709 Digital Computer of the P3 Approximation to the Boltzmann Transports equation in Cylindrical Geometry

Description: In formulating this general diffusion theory expression which represents the neutron balance in a nuclear chain reactor the following assumptions were made : (1) the medium through which the neutrons are diffusing has a low neutron capture cross section, (2) the region in which the flux distribute is being described is two or three mean free paths from strong sources and sinks or from a boundary. Certainly, is going to the lattice cell of a receptor, both of the above conditions are violated; f… more
Date: June 17, 1959
Creator: Matsumoto, D. D. & Richey, C. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Standard Definitions of Building Geometry for Energy Evaluation

Description: This document provides definitions and metrics of building geometry for use in building energy evaluation. Building geometry is an important input in the analysis process, yet there are no agreed-upon standard definitions of these terms for use in energy analysis. The metrics can be used for characterizing building geometry, for calculating energy performance metrics, and for conducting energy simulations.
Date: October 1, 2005
Creator: Deru, M. & Torcellini, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Allegory of Geometry

Description: A heavily robed female figure holds for display a sheet of paper upon which are geometric drawings. In the figure's left hand are a right angle and a compass. A globe, a serpent, an obilisk, a carved sarcophagus, and a sphinx round out the composition.
Access: Restricted to UNT Community Members. Login required if off-campus.
Date: 1649~
Creator: La Hyre, Laurent de
Item Type: Refine your search to only Artwork
Partner: UNT College of Visual Arts + Design
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The Maximum Size of Combinatorial Geometries Excluding Wheels and Whirls as Minors

Description: We show that the maximum size of a geometry of rank n excluding the (q + 2)-point line, the 3-wheel W_3, and the 3-whirl W^3 as minor is (n - 1)q + 1, and geometries of maximum size are parallel connections of (q + 1)-point lines. We show that the maximum size of a geometry of rank n excluding the 5-point line, the 4-wheel W_4, and the 4-whirl W^4 as minors is 6n - 5, for n ≥ 3. Examples of geometries having rank n and size 6n - 5 include parallel connections of the geometries V_19 and PG(2,3).
Date: August 1989
Creator: Hipp, James W. (James William), 1956-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Toward Interoperable Mesh, Geometry and Field Components for PDE Simulation Development

Description: Mesh-based PDE simulation codes are becoming increasingly sophisticated and rely on advanced meshing and discretization tools. Unfortunately, it is still difficult to interchange or interoperate tools developed by different communities to experiment with various technologies or to develop new capabilities. To address these difficulties, we have developed component interfaces designed to support the information flow of mesh-based PDE simulations. We describe this information flow and discuss typ… more
Date: July 11, 2005
Creator: Chand, K K; Diachin, L F; Li, X; Ollivier-Gooch, C; Seol, E S; Shephard, M et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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On complexity of the mixed volume of parallelograms

Description: Let K = (K{sub 1}...K{sub n}) be a n-tuple of convex compact subsets in the Euclidean space R{sup n}, and let V({center_dot}) be the Euclidean volume in R{sup n}. It is well known Herman Minkowski result (see for instance 5), that the value of the V{sub K}({gamma}{sub 1}K{sub 1} + ... {gamma}{sub n}K{sub n}) is a homogeneous polynomial of degree n, called the Minkowski polynomial, in nonnegative variables {gamma}{sub 1}...{gamma}{sub n1}, where '+' denotes Minkowski sum, and {gamma}K denotes th… more
Date: January 1, 2009
Creator: Gurvits, Leonid
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of Some Leading-Edge Modifications, Section and Plan-Form Variations, and Vertical Position on Low-Lift Wing Drag at Transonic and Supersonic Speeds

Description: Report presents information about free-flight rocket-propelled model testing to determine the effect of some wing geometry variables on low lift drag at a range of Mach numbers. Results regarding the effect of airfoil section, wing nose droop and nose flaps, plan form, and wing vertical position are provided.
Date: January 18, 1955
Creator: Welsh, Clement J.; Wallskog, Harvey A. & Sandahl, Carl A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Study of the Knowledge and Skills Required of Draftsmen in Descriptive Geometry, and What is Offered in Texas Junior Colleges

Description: This study was conducted to ascertain whether or not the opportunities for developing competencies in descriptive geometry needed by draftsmen in the Dallas -Fort Worth area are being provided in Texas junior colleges. Findings concerning the knowledge, skills, and equipment associated with descriptive geometry as it is presented in Texas junior colleges were compared with competencies in descriptive geometry that representatives of industry believe are important for successful draftsmen in com… more
Date: May 1972
Creator: Ewing, George E.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Root status and future developments

Description: In this talk the authors review the major additions and improvements made to the ROOT system in the last 18 months and present their plans for future developments. The additions and improvements range from modifications to the I/O sub-system to allow users to save and restore objects of classes that have not been instrumented by special ROOT macros, to the addition of a geometry package designed for building, browsing, tracking and visualizing detector geometries. Other improvements include enh… more
Date: October 1, 2003
Creator: al., Rene Brun et
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

National Mathematics Advisory Panel

Description: The U.S. Department of Education, in partnership with the Conference Board of Mathematical Sciences, hosted the first National Math Panel Forum on October 6-7, 2008. This page documents the Forum activities, which brought together various organizations and other interested parties.
Date: 2008
Creator: National Mathematics Advisory Panel
Item Type: Refine your search to only Website
Partner: UNT Libraries Government Documents Department
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