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A high-fluence fusion neutron source

Description: A conceptual design of a D-T fusion facility for continuous production of 14-MeV neutron wall loading from 5 to 10 MW/m/sup 2/ at the plasma surface is presented. In this design, D-T neutrons are produced in a linear, two-component plasma formed by neutral beam irradiation of a fully ionized warm plasma target. The beam energy, which is deposited in the center, is transferred to the warm plasma mainly by electron drag and is conducted along the target plasma column to end regions where it is ab… more
Date: February 17, 1988
Creator: Coensgen, F. H.; Casper, T. A.; Correll, D. L.; Damm, C. C.; Futch, A. H.; Logan, B. G. et al.
Partner: UNT Libraries Government Documents Department
open access

Surface roughness effects on the solar reflectance of cool asphalt shingles

Description: We analyze the solar reflectance of asphalt roofing shingles that are covered with pigmented mineral roofing granules. The reflecting surface is rough, with a total area approximately twice the nominal area. We introduce a simple analytical model that relates the 'micro-reflectance' of a small surface region to the 'macro-reflectance' of the shingle. This model uses a mean field approximation to account for multiple scattering effects. The model is then used to compute the reflectance of shingl… more
Date: February 17, 2008
Creator: Akbari, Hashem; Berdahl, Paul; Akbari, Hashem; Jacobs, Jeffry & Klink, Frank
Partner: UNT Libraries Government Documents Department
open access

Longitudinal Density Modulation and Energy Conversion in Intense Beams

Description: Density modulation of charged particle beams may occur as a consequence of deliberate action, or may occur inadvertently because of imperfections in the particle source or acceleration method. In the case of intense beams, where space charge and external focusing govern the beam dynamics, density modulation may under some circumstances be converted to velocity modulation, with a corresponding conversion of potential energy to kinetic energy. Whether this will occur depends on the properties of … more
Date: February 17, 2006
Creator: Harris, J; Neumann, J; Tian, K & O'Shea, P
Partner: UNT Libraries Government Documents Department
open access

Shaping metal nanocrystals through epitaxial seeded growth

Description: Morphological control of nanocrystals has becomeincreasingly important, as many of their physical and chemical propertiesare highly shape-dependent. Nanocrystal shape control for both single andmultiple material systems, however, remains fairly empirical andchallenging. New methods need to be explored for the rational syntheticdesign of heterostructures with controlled morphology. Overgrowth of adifferent material on well-faceted seeds, for example, allows for the useof the defined seed morphol… more
Date: February 17, 2008
Creator: Habas, Susan E.; Lee, Hyunjoo; Radmilovic, Velimir; Somorjai,Gabor A. & Yang, Peidong
Partner: UNT Libraries Government Documents Department
open access

The Nijmegen hyperon-nucleon potentials

Description: The Nijmegen YN potential models are reviewed. Differences with the models constructed by the Juelich group are highlighted. A mini- review is given of the status of the scalar mesons and their relevance for the NN and YN interactions. Finally, the reactions {bar N}N {yields} {bar Y}Y are discussed.
Date: February 17, 1994
Creator: Timmermans, R.
Partner: UNT Libraries Government Documents Department
open access

Experimental searches for magnetic monopoles. [Mass, probability, review]

Description: Analysis of the sensitivity of previous negative searches for magnetic monopoles shows that they constitute prior evidence against the monopole interpretation of the event reported as ''evidence for detection of a moving magnetic monopole''. The strength of the evidence varies with the unknown mass of the monopole. For M less than or equal to 10/sup 5/ GeV, odds are greater than 10/sup 6/ : 1 against. For larger masses, the limits depend strongly on assumptions about the range of monopoles and … more
Date: February 17, 1976
Creator: Ross, R. R.
Partner: UNT Libraries Government Documents Department
open access

Electron Anomalous Magnetic Moment in Basis Light-Front Quantization Approach

Description: We apply the Basis Light-Front Quantization (BLFQ) approach to the Hamiltonian field theory of Quantum Electrodynamics (QED) in free space. We solve for the mass eigenstates corresponding to an electron interacting with a single photon in light-front gauge. Based on the resulting non-perturbative ground state light-front amplitude we evaluate the electron anomalous magnetic moment. The numerical results from extrapolating to the infinite basis limit reproduce the perturbative Schwinger result w… more
Date: February 17, 2012
Creator: Zhao, Xingbo; Honkanen, Heli; Maris, Pieter; Vary, James P. & Brodsky, Stanley J.
Partner: UNT Libraries Government Documents Department
open access

Identification of a haloalkaliphilic and thermostable cellulase with improved ionic liquid tolerance

Description: Some ionic liquids (ILs) have been shown to be very effective solvents for biomass pretreatment. It is known that some ILs can have a strong inhibitory effect on fungal cellulases, making the digestion of cellulose inefficient in the presence of ILs. The identification of IL-tolerant enzymes that could be produced as a cellulase cocktail would reduce the costs and water use requirements of the IL pretreatment process. Due to their adaptation to high salinity environments, halophilic enzymes are… more
Date: February 17, 2011
Creator: Zhang, Tao; Datta, Supratim; Eichler, Jerry; Ivanova, Natalia; Axen, Seth D.; Kerfeld, Cheryl A. et al.
Partner: UNT Libraries Government Documents Department
open access

A New Green's Function for the Wake Potential Calculation of the SLAC S-band Constant Gradient Accelerating Section

Description: The behavior of the longitudinal wake fields excited by a very short bunch in the SLAC S-band constant gradient accelerating structures has been studied. Wake potential calculations were performed for a bunch length of 10 microns using the author's code to obtain a numerical solution of Maxwell's equations in the time domain. We have calculated six accelerating sections in the series (60-ft) to find the stationary solution. While analyzing the computational results we have found a new formula f… more
Date: February 17, 2012
Creator: Novokhatski, A,
Partner: UNT Libraries Government Documents Department
open access

Kirchhoff's Integral Representation and a Cavity Wake Potential

Description: A method is proposed for the calculation of the short-range wake field potentials of an ultra-relativistic bunch passing near some irregularities in a beam pipe. The method is based on the space-time domain integration of Maxwell's equations using Kirchhoff's formulation. We demonstrate this method on two cases where we obtain the wake potentials for the energy loss of a bunch traversing an iris-collimator in a beam pipe and for a cavity. Likewise, formulas are derived for Green's functions tha… more
Date: February 17, 2012
Creator: Novokhatski, Alexander
Partner: UNT Libraries Government Documents Department
open access

Precision Engineering within the National Ignition Campaign

Description: In this very brief talk, we'll discuss how precision engineering impacts 4 key areas of NIF: (1) Diamond turning of KDP crystals; (2) Mitigation of laser damage on optics; (3) Alignment of lasers, targets, diagnostics; (4) Target fabrication.
Date: February 17, 2010
Creator: Taylor, J S; Carlisle, K; Klingmann, J L; Geraghty, P; Saito, T T & Montesanti, R C
Partner: UNT Libraries Government Documents Department
open access

Ultrafast Enhancement of Ferromagnetism via Photoexcited Holes inGaMnAs

Description: We report on the observation of ultrafast photo-enhanced ferromagnetism in GaMnAs. It is manifested as a transient magnetization increase on a 100-ps time scale, after an initial sub-ps demagnetization. The dynamic magnetization enhancement exhibits a maximum below the Curie temperature {Tc} and dominates the demagnetization component when approaching {Tc}. We attribute the observed ultrafast collective ordering to the p-d exchange interaction between photoexcited holes and Mn spins, leading to… more
Date: February 17, 2007
Creator: Wang, J.; Cotoros, I.; Dani, K.M.; Liu, X.; Furdyna, J.K. & Chemla, D.S.
Partner: UNT Libraries Government Documents Department
open access

INSIGHTS INTO THE DYNAMIC RESPONSE OF TUNNELS IN JOINTED ROCKS

Description: Tunnels in jointed rocks can be subjected to severe dynamic loads because of rock bursts, coal bumps, and large earthquakes. A series of 3-dimensional simulations was performed, based on discrete element analysis to gain insights into the parameters that influence the response of such tunnels. The simulations looked at the effect of joint set orientation, the effect of joint spacing, the effect of peak displacement for a given peak velocity, the effect of pulse peak velocity for a given displac… more
Date: February 17, 2005
Creator: Heuze, F E & Morris, J P
Partner: UNT Libraries Government Documents Department
open access

Dystroglycan loss disrupts polarity and beta-casein induction inmammary epithelial cells by perturbing laminin anchoring

Description: Precise contact between epithelial cells and their underlying basement membrane is critical to the maintenance of tissue architecture and function. To understand the role that the laminin receptor dystroglycan (DG) plays in these processes, we assayed cell responses to laminin-111 following conditional ablation of DG expression in cultured mammary epithelial cells (MECs). Strikingly, DG loss disrupted laminin-111-induced polarity and {beta}-casein production, and abolished laminin assembly at t… more
Date: February 17, 2006
Creator: Weir, M. Lynn; Oppizzi, Maria Luisa; Henry, Michael D.; Onishi,Akiko; Campbell, Kevin P.; Bissell, Mina J. et al.
Partner: UNT Libraries Government Documents Department
open access

Beam Matching to a Plasma Wakefield Accelerator Using a Ramped Density Profile at the Plasma Boundary

Description: An important aspect of plasma wake field accelerators (PWFA) is stable propagation of the drive beam. In the under dense plasma regime, the drive beam creates an ion channel which acts on the beam as a strong thick focusing lens. The ion channel causes the beam to undergo multiple betatron oscillations along the length of the plasma. There are several advantages if the beam size can be matched to a constant radius. First, simulations have shown that instabilities such as hosing are reduced when… more
Date: February 17, 2006
Creator: Marsh, K. A.; Clayton, C. E.; Huang, C.; Johnson, D. K.; Joshi, C.; Lu, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Depth Dependence of the Mechanical Properties of Human Enamel by Nanoindentation

Description: Nanoindentation has recently emerged to be the primary method to study the mechanical behavior and reliability of human enamel. Its hardness and elastic modulus were generally reported as average values with standard deviations that were calculated from the results of multiple nanoindentation tests. In such an approach, it is assumed that the mechanical properties of human enamel are constant, independent of testing parameters, like indent depth and loading rate. However, little is known if the… more
Date: February 17, 2006
Creator: Zhou, J & Hsiung, L L
Partner: UNT Libraries Government Documents Department
open access

AMG by element agglomeration and constrained energy minimization interpolation

Description: This paper studies AMG (algebraic multigrid) methods that utilize energy minimization construction of the interpolation matrices locally, in the setting of element agglomeration AMG. The coarsening in element agglomeration AMG is done by agglomerating fine-grid elements, with coarse element matrices defined by a local Galerkin procedure applied to the matrix assembled from the individual fine-grid element matrices. This local Galerkin procedure involves only the coarse basis restricted to the a… more
Date: February 17, 2006
Creator: Kolev, T V & Vassilevski, P S
Partner: UNT Libraries Government Documents Department
open access

Living with genome instability: the adaptation of phytoplasmas todiverse environments of their insect and plant hosts

Description: Phytoplasmas (Candidatus Phytoplasma, Class Mollicutes) cause disease in hundreds of economically important plants, and are obligately transmitted by sap-feeding insects of the order Hemiptera, mainly leafhoppers and psyllids. The 706,569-bp chromosome and four plasmids of aster yellows phytoplasma strain witches broom (AY-WB) were sequenced and compared to the onion yellows phytoplasma strain M (OY-M) genome. The phytoplasmas have small repeat-rich genomes. The repeated DNAs are organized into… more
Date: February 17, 2006
Creator: Bai, Xiaodong; Zhang, Jianhua; Ewing, Adam; Miller, Sally A.; Radek, Agnes; Shevchenko, Dimitriy et al.
Partner: UNT Libraries Government Documents Department
open access

Automatic segmentation of histological structures in mammary gland tissue sections

Description: Real-time three-dimensional (3D) reconstruction of epithelial structures in human mammary gland tissue blocks mapped with selected markers would be an extremely helpful tool for breast cancer diagnosis and treatment planning. Besides its clear clinical application, this tool could also shed a great deal of light on the molecular basis of breast cancer initiation and progression. In this paper we present a framework for real-time segmentation of epithelial structures in two-dimensional (2D) imag… more
Date: February 17, 2004
Creator: Fernandez-Gonzalez, Rodrigo; Deschamps, Thomas; Idica, Adam K.; Malladi, Ravikanth & Ortiz de Solorzano, Carlos
Partner: UNT Libraries Government Documents Department
open access

Stabilization and disposal of Argonne-West low-level mixed wastes in ceramicrete waste forms.

Description: The technology of room-temperature-setting phosphate ceramics or Ceramicrete{trademark} technology, developed at Argonne National Laboratory (ANL)-East is being used to treat and dispose of low-level mixed wastes through the Department of Energy complex. During the past year, Ceramicrete{trademark} technology was implemented for field application at ANL-West. Debris wastes were treated and stabilized: (a) Hg-contaminated low-level radioactive crushed light bulbs and (b) low-level radioactive Pb… more
Date: February 17, 1998
Creator: Barber, D. B.; Singh, D.; Strain, R. V.; Tlustochowicz, M. & Wagh, A. S.
Partner: UNT Libraries Government Documents Department
open access

Microbial Forensics: A Scientific Assessment

Description: Microorganisms have been used as weapons in criminal acts, most recently highlighted by the terrorist attack using anthrax in the fall of 2001. Although such ''biocrimes'' are few compared with other crimes, these acts raise questions about the ability to provide forensic evidence for criminal prosecution that can be used to identify the source of the microorganisms used as a weapon and, more importantly, the perpetrator of the crime. Microbiologists traditionally investigate the sources of mic… more
Date: February 17, 2003
Creator: Keim, Paul
Partner: UNT Libraries Government Documents Department
open access

HRTEM at half-Angstrom resolution: From OAM to TEAM

Description: Transmission electron microscopy (TEM) at sub-Angstrom resolution is important for nanotechnology. Identifying atom positions requires appropriate resolution, the ability to separate distinct objects in images. With Cs corrected, the information limit of the TEM controls resolution. The OAM has demonstrated that a resolution of 0.78A is possible. The TEAM (transmission electron achromatic microscope) will be a TEM using hardware correction of Cs with a monochromator to improve its information l… more
Date: February 17, 2003
Creator: O'Keefe, Michael A.
Partner: UNT Libraries Government Documents Department
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