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Melting of bcc Transition Metals and Icosahedral Clustering

Description: In contrast to polyvalent metals, transition metals have low melting slopes(dT/dP) that are due to partially filled d-bands that allow for a lowering of liquid phase energy through s-d electron transfer and the formation of local structures. In the case of bcc transition metals we show the apparent discrepancy of DAC melting measurements with shock melting of Mo can be understood by reexamining the shock data for V and Ta and introducing the presence of an icosahedral short range order (ISRO) m… more
Date: May 26, 2006
Creator: Ross, M; Boehler, R & Japel, S
Partner: UNT Libraries Government Documents Department
open access

Towards an Accurate Performance Modeling of Parallel SparseFactorization

Description: We present a performance model to analyze a parallel sparseLU factorization algorithm on modern cached-based, high-end parallelarchitectures. Our model characterizes the algorithmic behavior bytakingaccount the underlying processor speed, memory system performance, aswell as the interconnect speed. The model is validated using theSuperLU_DIST linear system solver, the sparse matrices from realapplications, and an IBM POWER3 parallel machine. Our modelingmethodology can be easily adapted to stud… more
Date: May 26, 2006
Creator: Grigori, Laura & Li, Xiaoye S.
Partner: UNT Libraries Government Documents Department
open access

EUV mask reflectivity measurements with micron-scale spatial resolution

Description: The effort to produce defect-free mask blanks for EUV lithography relies on increasing the detection sensitivity of advanced mask inspection tools, operating at several wavelengths. We describe the unique measurement capabilities of a prototype actinic (EUV wavelength) microscope that is capable of detecting small defects and reflectivity changes that occur on the scale of microns to nanometers. Types of defects: (a) Buried Substrate Defects: particles & pits (causes amplitude and/or phase vari… more
Date: May 26, 2008
Creator: Goldberg, Kenneth A.; Rekawa, S. B.; Kemp, C. D.; Barty, A.; Anderson, E. H.; Kearney, Patrick et al.
Partner: UNT Libraries Government Documents Department
open access

Visualization of Excitonic Structure in the Fenna-Matthews-OlsonPhotosynthetic Complex by Polarization-Dependent Two-DimensionalElectronic Spectroscopy

Description: Photosynthetic light-harvesting proceeds by the collection and highly efficient transfer of energy through a network of pigment-protein complexes. Inter-chromophore electronic couplings and interactions between pigments and the surrounding protein determine energy levels of excitonic states and dictate the mechanism of energy flow. The excitonic structure (orientation of excitonic transition dipoles) of pigment-protein complexes is generally deduced indirectly from x-ray crystallography in comb… more
Date: May 26, 2008
Creator: Department of Chemistry, The University of Chicago; Department of Biology, Department of Chemistry, Washington University; Fleming, Graham; Read, Elizabeth L.; Schlau-Cohen, Gabriela S.; Engel, Gregory S. et al.
Partner: UNT Libraries Government Documents Department
open access

Proteomic Analysis of Calcium- and Phosphorylation-dependentCalmodulin Complexes in Mammalian Cells

Description: Protein conformational changes due to cofactor binding (e.g. metal ions, heme) and/or posttranslational modifications (e.g. phosphorylation) modulate dynamic protein complexes. Calmodulin (CaM) plays an essential role in regulating calcium (Ca{sup 2+}) signaling and homeostasis. No systematic approach on the identification of phosphorylation-dependent Ca{sup 2+}/CaM binding proteins has been published. Herein, we report a proteome-wide study of phosphorylation-dependent CaM binding proteins fro… more
Date: May 26, 2006
Creator: Jang, Deok-Jin & Wang, Daojing
Partner: UNT Libraries Government Documents Department
open access

Abrupt onset of a second energy gap at the superconducting transition of underdoped Bi2212

Description: he superconducting gap--an energy scale tied to the superconducting phenomena--opens on the Fermi surface at the superconducting transition temperature (Tc) in conventional BCS superconductors. In underdoped high-Tc superconducting copper oxides, a pseudogap (whose relation to the superconducting gap remains a mystery) develops well above Tc (refs 1, 2). Whether the pseudogap is a distinct phenomenon or the incoherent continuation of the superconducting gap above Tc is one of the central questi… more
Date: May 26, 2007
Creator: Hussain, Zahid; Lee, W. S.; Vishik, I. M.; Tanaka, K.; Lu, D. H.; Sasagawa, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Determining the critical size of EUV mask substrate defects

Description: Determining the printability of substrate defects beneath the extreme ultraviolet (EUV) reflecting multilayer stack is an important issue in EUVL lithography. Several simulation studies have been performed in the past to determine the tolerable defect size on EUV mask blank substrates but the industry still has no exact specification based on real printability tests. Therefore, it is imperative to experimentally determine the printability of small defects on a mask blanks that are caused by sub… more
Date: May 26, 2008
Creator: Goldberg, Kenneth A.; Gullikson, Eric M.; Han, Hakseung; Cho, Wonil; Jeon, Chan-Uk & Wurm, Stefan
Partner: UNT Libraries Government Documents Department
open access

Microprocessor control and data acquisition at the LLNL 100-MeV accelerator

Description: A distributed microprocessor control and data acquisition network has been designed for implementation on the Lawrence Livermore National Laboratory 100 MeV electron/positron accelerator (LINAC). The system has been designed to be as transparent to the user as possible by stressing responsiveness, reliability, and relevance of data presented to the user. Implementation of the network will take place in modular fashion in three stages, so as to minimize disruption of normal operations. The first… more
Date: May 26, 1981
Creator: Mendonca, M.L.
Partner: UNT Libraries Government Documents Department
open access

Nuclear design of the LLL-GA U/sub 3/Si blanket

Description: The nuclear design analysis and performance of the blanket for the Pu/sup 239/ producing standard mirror hybrid is discussed. The blanket is based on present day materials and technology. It is designed for peak power density and burnup in the uranium fuel of 500 W/cc and 3 atom percent. The blanket produces 2.0 Mg/yr of Pu-239 (net) from 400 MW fusion (D-T) and depleted uranium and has an average energy multiplication of 11.
Date: May 26, 1978
Creator: Lee, J. D.
Partner: UNT Libraries Government Documents Department
open access

A new glove-box system for a high-pressure tritium pump

Description: A new glove-box system that was designed around a high-pressure tritium pump is described. The system incorporates new containment ideas such as ''burpler'' passive pressure controls, valves that can be turned from outside the box, inflatable door seals, ferro-fluidic motor-shaft seals, and rapid box-to-hood conversion during cryostaging. Currently under construction, the system will contain nine separate sections with automatic pressure-balancing and venting systems. 3 refs., 5 figs.
Date: May 26, 1988
Creator: Wilson, S. W.; Borree, R. J.; Chambers, D. I.; Chang, Y.; Merrill, J. T.; Souers, P. C. et al.
Partner: UNT Libraries Government Documents Department
open access

Tandem Mirror Reactor

Description: A reactor based on this concept that produces 1000 MWe consists of a solenoidal magnet about 50 to 100 m long. A cylindrical blanket is used for energy recovery and tritium breeding. Thus the reactor itself is simple and of low technology. The end plugs, however, are of high technology, having the high magnetic fields needed to confine the high-pressure plasma and the high injection energy (0.6 to 1.2 MeV) needed to achieve good magnetic confinement. A low technology, compact, economical hybrid… more
Date: May 26, 1978
Creator: Moir, R.W.; Barr, W.L. & Bender, D.J.
Partner: UNT Libraries Government Documents Department
open access

Effects of local mass anomalies in Eoetvoes-like experiments

Description: We consider in detail the effects of local mass anomalies in Eoetvoes-like experiments. It is shown that in the presence of an intermediate-range non-gravitational force, the dominant contributions to both the sign and magnitude of the Eoetvoes anomaly may come from nearby masses and not from the earth as a whole. This observation has important implications in the design and interpretation of future experiments, and in the formulation of unified theories incorporating new intermediate-range for… more
Date: May 26, 1986
Creator: Talmadge, C.; Aronson, S.H. & Fischbach, E.
Partner: UNT Libraries Government Documents Department
open access

Charge exchange losses during cyclotron acceleration: experiment and theory

Description: Quantitative estimates of charge exchange (CE) losses during acceleration are very important in the design and operation of heavy ion cyclotrons. Such estimates have been made using a vacuum model computer code which was developed to establish vacuum requirements for the MSU superconducting heavy ion cyclotron. This code uses pressure and cross-section data to calculate the radial loss of beam due to charge exchange. Since CE cross sections and radial pressure profiles are not always well known… more
Date: May 26, 1978
Creator: Gough, R.A. & Mallory, M.L.
Partner: UNT Libraries Government Documents Department
open access

A Structural Determination Using Magnetic X-Ray Circular Dichroism in Spin-Polarized Photoelectron Diffraction

Description: The first structural determination with spin-polarized, energy-dependent photoelectron diffraction using circularly-polarized x-rays is reported for Fe films on Cu(001). Circularly-polarized x-rays produce spin-polarized photoelectrons from the Fe 2p doublet, and intensity asymmetries in the 2p{sup 3/2} level are observed. . Fully spin-specific multiple scattering calculations reproduce the experimentally determined energy and angular dependences. A new analytical procedure which focuses upon i… more
Date: May 26, 1994
Creator: Waddill, G. D.; Tobin, J. G.; Guo, X. & Tong, S. Y.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the polarization in the decay B{sup 0} {yields} J/{psi}K{sup *0} in {bar p}p collisions at {radical}s = 1.8 TeV

Description: This paper reports on the measurement of the polarization in the decay B{sup o} {yields} J/{psi}K{sup *o} using data collected at the collider Detector at Fermilab in {bar p}p collisions at {radical}s = 1.8 TeV. B{sup O} mesons were reconstructed through the decay chain B{sup o} {yields} J/{psi}K{sup *o}, J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}, K{sup *o} {yields} K{sup +}{pi}{sup {minus}}. A sample of 50 {plus_minus} 11 events was used in the measurement, yielding the result {Gamma}{sub … more
Date: May 26, 1994
Creator: CDF Collaboration
Partner: UNT Libraries Government Documents Department
open access

Beryllium based multilayers for normal incidence extreme ultraviolet reflectivity

Description: The need for normal incidence mirrors maintaining reflectivity greater than 60% for an industrially competitive Extreme Ultraviolet Lithography (EUV) system has been well documented. The Molybdenum/Silicon system has emerged as the de-facto standard, where researchers are now routinely fabricating mirrors demonstrating 63% reflectivity near 130 Angstroms. However, multilayer mirrors using beryllium as the low atomic number (low-Z) spacer could potentially show similar or better reflectivity, an… more
Date: May 26, 1994
Creator: Skulina, K. M.; Alford, C.; Bionta, R. M.; Makowiecki, D. M.; Kortright, J.; Soufli, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Power conditioning for the National Ignition Facility

Description: A cost-effective, 320-MJ power-conditioning system has been completed for the proposed National Ignition Facility (NIF). The design features include metallized dielectric capacitors, a simple topology, and large (1.6-MJ) module size. Experimental results address the technical risks associated with the design.
Date: May 26, 1994
Creator: Larson, D. W.; Anderson, R. & Boyes, J.
Partner: UNT Libraries Government Documents Department
open access

RECENT TEST RESULTS OF THE FAST-PULSED 4 T COS DIPOLE GSI 001.

Description: For the FAIR-project at GSI a model dipole was built at BNL with the nominal field of 4 T and a nominal ramp rate of 1 T/S. The magnet design was similar to the RHIC dipole, with some changes for loss reduction and better cooling. The magnet was already successfully tested in a vertical cryostat, with good training behavior. Cryogenic losses were measured and first results of field harmonics were published. However, for a better understanding of the cooling process, quench currents at several r… more
Date: May 26, 2005
Creator: Moritz, G.; Kaugerts, J.; Escallier, J.; Ganetis, G.; Jain, A.; Marone, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Massive-scale RDF Processing Using Compressed Bitmap Indexes

Description: The Resource Description Framework (RDF) is a popular data model for representing linked data sets arising from the web, as well as large scienti#12;c data repositories such as UniProt. RDF data intrinsically represents a labeled and directed multi-graph. SPARQL is a query language for RDF that expresses subgraph pattern-#12;nding queries on this implicit multigraph in a SQL- like syntax. SPARQL queries generate complex intermediate join queries; to compute these joins e#14;ciently, we propose … more
Date: May 26, 2011
Creator: Madduri, Kamesh & Wu, Kesheng
Partner: UNT Libraries Government Documents Department
open access

Raman Spectroscopy of Lithium Hydride Corrosion: Selection of an Appropriate Excitation Wavelength to Minimize Fluorescence

Description: The recent interest in a hydrogen-based fuel economy has renewed research into metal hydride chemistry. Many of these compounds react readily with water to release hydrogen gas and form a caustic. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFT) has been used to study the hydrolysis reaction. The LiOH stretch appears at 3670 cm{sup -1}. Raman spectroscopy is a complementary technique that employs monochromatic excitation (laser) allowing access to the low energy region of the… more
Date: May 26, 2011
Creator: Stowe, A. C. & Smyrl, N. R.
Partner: UNT Libraries Government Documents Department
open access

Scoping economics for the commercial manufacture of metallocene catalysts

Description: This study assumes that commercial-scale production of propylene-based isotactic polymers with metallocene catalyst systems will become a reality. The challenge that must be overcome for commercial success with these propylene polymers is to discover a metallocene system recipe that will give sufficient catalyst activity along with the requisite stereo-selectivity at reasonable cost. Anticipating such a discovery, it is assumed here that the economics are well-represented by a catalyst system t… more
Date: May 26, 1994
Creator: Brockmeier, N. F.
Partner: UNT Libraries Government Documents Department
open access

Simulation Results for the New NSTX HHFW Antenna Straps Design by Using Microwave Studio

Description: Experimental results have shown that the high harmonic fast wave (HHFW) at 30 MHz can provide substantial plasma heating and current drive for the NSTX spherical tokamak operation. However, the present antenna strap design rarely achieves the design goal of delivering the full transmitter capability of 6 MW to the plasma. In order to deliver more power to the plasma, a new antenna strap design and the associated coaxial line feeds are being constructed. This new antenna strap design features tw… more
Date: May 26, 2009
Creator: Kung, C. C.; Brunkhorst, C.; Greenough, N.; Fredd, E.; Castano, A.; Miller, D. et al.
Partner: UNT Libraries Government Documents Department
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