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Constructibility issues associated with a nuclear waste repository in basalt (open access)

Constructibility issues associated with a nuclear waste repository in basalt

This report contains the text and slide reproductions of a speech on nuclear waste disposal in basalt. The presentation addresses the layout of repository access shafts and subsurface facilities resulting from the conceptual design of a nuclear repository in basalt. The constructibility issues that must be resolved prior to construction are described. (DMC)
Date: December 4, 1981
Creator: Turner, D.A.
System: The UNT Digital Library
Magnetic and inertial fusion status and development plans (open access)

Magnetic and inertial fusion status and development plans

Controlled fusion, pursued by investigators in both the magnetic and inertial confinement research programs, continues to be a strong candidate as an intrinsically safe and virtually inexhaustible long-term energy source. We describe the status of magnetic and inertial confinement fusion in terms of the accomplishments made by the research programs for each concept. The improvement in plasma parameters (most frequently discussed in terms of the Tn tau product of ion temperature, T, density, n, and confinement time, tau) can be linked with the construction and operation of experimental facilities. The scientific progress exhibited by larger scale fusion experiments within the US, such as Princeton Plasma Physics Laboratory's Fusion Test Reactor for magnetic studies and Lawrence Livermore National Laboratory's Nova laser for inertial studies, has been optimized by the theoretical advances in plasma and computational physics. Both TFTR and Nova have exhibited ion temperatures in excess of 10 keV at confinement parameters of n tau near 10/sup 13/ cm/sup -3/ . sec. At slightly lower temperatures (near a few keV), the value of n tau has exceeded 10/sup 14/ cm/sup -3/ . sec in both devices. Near-term development plans in fusion research include experiments within the US, Europe, and Japan to …
Date: December 4, 1987
Creator: Correll, D. & Storm, E.
System: The UNT Digital Library
Interactive computerized laboratory data management system (open access)

Interactive computerized laboratory data management system

In support of this effort, an average of 55 samples with approximately 4 analyses per sample comes into the ICPP analytical laboratory each day. Information concerning these samples, the 60 people handling the samples, and the 90 methods of running samples is registered, processed, and accessed daily. A manual paper system was found to be inadequate for an efficient, accurate, interacting network; thus, the need for a more spontaneous system emanated. The Analytical Laboratory Computer System is designed to automate and streamline the generation and storage of this data and to increase the credibility of sample results. A 256 K byte Data General Eclipse C/300, a 62 K byte Hewlett-Packard 9845A, and 8 Tetronix 4023 terminals are being used to achieve this goal. The Eclipse is used for data input-output and the calculation and bias correction of laboratory results; the 9845 computer is used for data manipulation for quality control. Utilization of the data provides some powerful tools in such areas as quality control, data classification, and analyst/method performance evaluation. The simplicity and clarity of operating the system as well as the complexities of design and implementation are also discussed.
Date: December 4, 1979
Creator: Mirrop, C. A.; Baldwin, J. M.; Camarata, A. R.; Halverson, G. D.; Hand, R. L.; Wade, M. A. et al.
System: The UNT Digital Library
R. Bruce Merrifield and Solid-Phase Peptide Synthesis: A Historical Assessment (open access)

R. Bruce Merrifield and Solid-Phase Peptide Synthesis: A Historical Assessment

Bruce Merrifield, trained as a biochemist, had to address three major challenges related to the development and acceptance of solid-phase peptide synthesis (SPPS). The challenges were (1) to reduce the concept of peptide synthesis on a insoluble support to practice, (2) overcome the resistance of synthetic chemists to this novel approach, and (3) establish that a biochemist had the scientific credentials to effect the proposed revolutionary change in chemical synthesis. How these challenges were met is discussed in this article.
Date: December 4, 2007
Creator: Mitchell, A R
System: The UNT Digital Library
Measurement of the B to Xs gammaBranching Fraction and Photon Energy Spectrum usingthe Recoil Method (open access)

Measurement of the B to Xs gammaBranching Fraction and Photon Energy Spectrum usingthe Recoil Method

We present a measurement of the branching fraction and photon energy spectrum for the decay B {yields} X{sub s}{gamma} using data from the BABAR experiment. The data sample corresponds to an integrated luminosity of 210 fb{sup -1}, from which approximately 680,000 B{bar B} events are tagged by a fully reconstructed hadronic decay of one of the B mesons. In the decay of the second B meson, an isolated high-energy photon is identified. We measure {Beta}(B {yields} X{sub s}{gamma}) = (3.66 {+-} 0.85{sub stat} {+-} 0.60{sub syst}) x 10{sup -4} for photon energies E{sub {gamma}} above 1.9 GeV in the B rest frame. From the measured spectrum we calculate the first and second moments for different minimum photon energies, which are used to extract the heavy-quark parameters m{sub b} and {mu}{sub {pi}}{sup 2}. In addition, measurements of the direct CP asymmetry and isospin asymmetry are presented.
Date: December 4, 2007
Creator: Aubert, B.
System: The UNT Digital Library
CHARACTERIZATION OF SPATIAL HETEROGENIETIES IN DETECTOR GRADE CDZNTE (open access)

CHARACTERIZATION OF SPATIAL HETEROGENIETIES IN DETECTOR GRADE CDZNTE

Synthetic Cd{sub 1-x}Zn{sub x}Te or 'CZT' crystals are highly suitable for the room temperature-based spectroscopy of gamma radiation. Structural/morphological heterogeneities within CZT, such as secondary phases that are thought to consist of Te metal and have detrimental impacts on detector performance. In this study, we used electron and X-ray-based imaging techniques to examine heterogeneous properties of detector grade CZT. Using experimental analytical techniques rather than arbitrary theoretical definitions, our study identifies two dominant secondary phase morphologies. The first consists of numerous empty, 20 {micro} m wide, pyramidal bodies (tetrahedra) or 'negative' crystals with trace quantities of particulate residue that exist as 65 nm sized particles containing Si, Cd, Zn, and Te. The other consists of 20 {micro}m hexagonal-shaped bodies, which are composites of metallic Te layers that contain a teardrop-shaped core of amorphous and polycrystalline CdZnTe which finally surrounds an irregular-shaped void.
Date: December 4, 2007
Creator: Duff, M
System: The UNT Digital Library
On the Equivalence of Nonnegative Matrix Factorization and K-means- Spectral Clustering (open access)

On the Equivalence of Nonnegative Matrix Factorization and K-means- Spectral Clustering

We provide a systematic analysis of nonnegative matrix factorization (NMF) relating to data clustering. We generalize the usual X = FG{sup T} decomposition to the symmetric W = HH{sup T} and W = HSH{sup T} decompositions. We show that (1) W = HH{sup T} is equivalent to Kernel K-means clustering and the Laplacian-based spectral clustering. (2) X = FG{sup T} is equivalent to simultaneous clustering of rows and columns of a bipartite graph. We emphasizes the importance of orthogonality in NMF and soft clustering nature of NMF. These results are verified with experiments on face images and newsgroups.
Date: December 4, 2005
Creator: Ding, Chris; He, Xiaofeng; Simon, Horst D. & Jin, Rong
System: The UNT Digital Library
Charmless Hadronic B Decays at BaBar (open access)

Charmless Hadronic B Decays at BaBar

We report recent measurements for the branching fractions of charmless hadronic B decays obtained from data collected by the BABAR detector at the PEP-II asymmetric-energy collider at the Stanford Linear Accelerator Center.
Date: December 4, 2007
Creator: Burke, James P.
System: The UNT Digital Library
Observation of Y(3940) to J/psi omega in B to J/psi omega K at BABAR (open access)

Observation of Y(3940) to J/psi omega in B to J/psi omega K at BABAR

The authors report the results of a study of the decays B{sup +} {yields} J/{psi}{omega}K{sup +} and B{sup 0} {yields} J/{psi}{omega}K{sub S}{sup 0} using 383 million B{bar B} events from {Upsilon}(4S) decays with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage rings. They observe evidence for Y(3940) {yields} J/{psi}{omega} with product branching fractions {Beta}(B{sup +} {yields} Y K{sup +}, Y {yields} J/{psi}{omega}) = (4.9 {+-} 1.0(stat) {+-} 0.5(syst)) x 10{sup -5} and {Beta}(B{sup 0} {yields} Y K{sup 0}, Y {yields} J/{psi}{omega}) = (1.5{sub -1.2}{sup +1.4}(stat){sub -0.2}{sup +0.2}(syst)) x 10{sup -5}. The measured mass and width are M(Y) = (3914.6{sub -3.4}{sup +3.8}(stat){sub -1.9}{sup +1.9}(syst)) MeV/c{sup 2} and {Lambda}(Y) = (33{sub -8}{sup +12}(stat){sub -5}{sup +5}(syst)) MeV, respectively.
Date: December 4, 2007
Creator: Aubert, B.
System: The UNT Digital Library
A Cartesian embedded boundary method for hyperbolic conservation laws (open access)

A Cartesian embedded boundary method for hyperbolic conservation laws

The authors develop an embedded boundary finite difference technique for solving the compressible two- or three-dimensional Euler equations in complex geometries on a Cartesian grid. The method is second order accurate with an explicit time step determined by the grid size away from the boundary. Slope limiters are used on the embedded boundary to avoid non-physical oscillations near shock waves. They show computed examples of supersonic flow past a cylinder and compare with results computed on a body fitted grid. Furthermore, they discuss the implementation of the method for thin geometries, and show computed examples of transonic flow past an airfoil.
Date: December 4, 2006
Creator: Sjogreen, B & Petersson, N A
System: The UNT Digital Library
Applications of level structure modeling of odd-odd deformed nuclei (open access)

Applications of level structure modeling of odd-odd deformed nuclei

None
Date: December 4, 1984
Creator: Hoff, R. W.; Gardner, D. G.; Gardner, M. A.; Kern, J.; Piepenbring, R.; Boisson, J. P. et al.
System: The UNT Digital Library
A comparative study of short range order in Fe-Cr and Fe-V alloys around equiatomic composition (open access)

A comparative study of short range order in Fe-Cr and Fe-V alloys around equiatomic composition

Configurational energies have been calculated for equiatomic Fe-Cr and Fe-V alloys possessing the high temperature bcc crystalline structure, within a first principles electronic band structure approach. In agreement with experimental facts, a tendency towards order, with a B2 ordered structure of CsCl type, is found for FeV whereas phase separation characterized FeCr. These results suggest that the nature of short range order in the high temperature bcc solid solution is not the primary driving force for describing the structural transformation from bcc to sigma which takes place in both alloys upon decreasing temperature. 15 refs., 9 figs., 1 tab.
Date: December 4, 1990
Creator: Turchi, P.E.A.; Sluiter, M. (Lawrence Livermore National Lab., CA (USA)) & Stocks, G.M. (Oak Ridge National Lab., TN (USA))
System: The UNT Digital Library
Conference on legal aspects of geothermal development (open access)

Conference on legal aspects of geothermal development

Fifteen papers and abstracts are included. Separate abstracts were prepared for six papers and nine abstracts were listed by title.
Date: December 4, 1981
Creator: unknown
System: The UNT Digital Library
Applying IEEE storage system management standards at the National Storage Laboratory (open access)

Applying IEEE storage system management standards at the National Storage Laboratory

Since its inception in 1990, the IEEE Storage System Standards Working Group has identified storage-system management as an area in need of further development The pressing need for standards in storage-system management arises from the requirement to exchange management information and to provide control in a consistent predictable manner between the components of a storage system. An appropriate set of management standards will allow multiple vendors to supply storage management subsystems or applications that are integral to or compatible with new storage systems conforming to future IEEE standards. An early, practical application of IEEE storage-system-management work is being pursued at the National Storage Laboratory (NSL), a recently-formed industrial collaboration at Lawrence Livermore National Laboratory. The NSL`s purpose is to develop advanced hardware and software technologies for high-performance, distributed storage systems. Since storage system management is of critical concern, it is being explored in depth at the NSL. Work was initiated to define basic management requirements and develop generalized graphical-user-interface tools using remote-procedure-call mechanisms to implement the NSL`s conceptual management framework. Several constraints were imposed on the development of early versions of this work to maintain compatibility with the NSL`s underlying UniTree-based software architecture and to provide timely prototypes and proof …
Date: December 4, 1992
Creator: Louis, S. & Hyer, S. W.
System: The UNT Digital Library
Interferometric Studies of Laser-Created Plasmas Using Compact Soft X-Ray Lasers (open access)

Interferometric Studies of Laser-Created Plasmas Using Compact Soft X-Ray Lasers

We summarize results of several successful dense plasma diagnostics experiments realized by combining two different kinds of table-top soft x-ray lasers with an amplitude division interferometer based on diffraction grating beam splitters. In the first set of experiments this robust high throughput diffraction grating interferometer (DGI) was used with a 46.9 nm portable capillary discharge laser to study the dynamics of line focus and point focus laser-created plasmas. The measured electron density profiles, which differ significantly from those expected from a classical expansion, unveil important two-dimensional effects of the dynamics of these plasmas. A second DGI customized to operate in combination with a 14.7 nm Ni-like Pd transient gain laser was used to perform interferometry of line focus laser-created plasmas with picosecond time resolution. These measurements provide valuable new benchmarks for complex hydrodynamic codes and help bring new understanding of the dynamics of dense plasmas. The instrumentation and methodology we describe is scalable to significantly shorter wavelengths, and constitutes a promising scheme for extending interferometry to the study of very dense plasmas such as those investigated for inertial confinement fusion.
Date: December 4, 2003
Creator: Dunn, J.; Nilsen, J.; Moon, S.; Keenan, R.; Jankowska, E.; Maconi, M. C. et al.
System: The UNT Digital Library
Hydride precipitation crack propagation in zircaloy cladding during a decreasing temperature history (open access)

Hydride precipitation crack propagation in zircaloy cladding during a decreasing temperature history

An assessment of safety, design, and cost tradeoff issues for short (ten to fifty years) and longer (fifty to hundreds of years) interim dry storage of spent nuclear fuel in Zircaloy rods shall address potential failures of the Zircaloy cladding caused by the precipitation response of zirconium hydride platelets. If such assessment analyses are to be done rigorously, they will be necessarily complex because the precipitation response of zirconium hydride platelets is a stochastic functional of hydrogen concentration, temperature, stress, fabrication defect/texture structures, and flaw sizes of the cladding. Thus, there are, and probably always will be, zirhydride questions to analytically and experimentally resolve concerning the consistency, the completeness, and the certainty of models, data, the initial and the time-dependent boundary conditions. Some resolution of these questions will be required in order to have a defensible preference and tradeoffs decision analysis for assessing risks and consequences of the potential zirhydride induced cladding failures during dry storage time intervals. In the following brief discussion, one of these questions is posed as a consequence of an anomaly described in data reproducibility that was reported in the results of tests for hydrogen induced delayed cracking. The testing anomaly consisted of observing a significant …
Date: December 4, 2000
Creator: Stout, R B
System: The UNT Digital Library
DECOMMISSIONING AND ENVRIONMENTAL CLEANUP OF SMALL ARMS TRAINING FACILITY (open access)

DECOMMISSIONING AND ENVRIONMENTAL CLEANUP OF SMALL ARMS TRAINING FACILITY

USDOE performed a (CERCLA) non-time critical removal (NTCR) action at the Small Arms Training Area (SATA) Site Evaluation Area (SEA) located at the Savannah River Site (SRS), in Aiken, South Carolina. From 1951 to May 2010, the SATA was used as a small weapons practice and qualifying firing range. The SATA consisted of 870.1 ha (2,150 ac) of woodlands and open field, of which approximately 2.9 ha (7.3 ac) were used as a firing range. The SATA facility was comprised of three small arms ranges (one static and two interactive), storage buildings for supplies, a weapons cleaning building, and a control building. Additionally, a 113- m (370-ft) long earthen berm was used as a target backstop during live-fire exercises. The berm soils accumulated a large amount of spent lead bullets in the berm face during the facilities 59- years of operation. The accumulation of lead was such that soil concentrations exceeded the U.S. Environmental Protection Agency (USEPA) residential and industrial worker regional screening levels (RSLs). The RSL threshold values are based on standardized exposure scenarios that estimate contaminant concentrations in soil that the USEPA considers protective of humans over a lifetime. For the SATA facility, lead was present in soil …
Date: December 4, 2012
Creator: Kmetz, T.
System: The UNT Digital Library
Design of an RF Feed System for Standing-wave Accelerator Structures (open access)

Design of an RF Feed System for Standing-wave Accelerator Structures

We are investigating a standing wave accelerator structure that uses a rf feed to each individual cell. This approach minimizes rf power flow and electromagnetic energy absorbed by an rf breakdown. The objective of this work is a robust high-gradient (above 100 MV/m) X-band accelerator structure.
Date: December 4, 2012
Creator: Neilson, J.; Tantawi, S.G. & Dolgashev, V.A.
System: The UNT Digital Library
High-brightness Electron Beam Evolution in Time Following Laser-based Cleaning of the LCLS Cathode (open access)

High-brightness Electron Beam Evolution in Time Following Laser-based Cleaning of the LCLS Cathode

None
Date: December 4, 2012
Creator: Zhou, F.; Brachmann, A.; Decker, F. -J.; Emma, P.; Iverson, R.; Stefan, P. et al.
System: The UNT Digital Library
High-brightness Electron Beam Evolution Following Laser-based Cleaning of a Photocathode (open access)

High-brightness Electron Beam Evolution Following Laser-based Cleaning of a Photocathode

None
Date: December 4, 2012
Creator: Zhou, F.; Brachmann, A.; Decker, F -J.; Emma, P.; Gilevich, S.; Iverson, R. et al.
System: The UNT Digital Library
The use of dimorphic Alu insertions in human DNA fingerprinting (open access)

The use of dimorphic Alu insertions in human DNA fingerprinting

We have characterized certain Human Specific Alu Insertions as either dimorphic (TPA25, PV92, APO), sightly dimorphic (C2N4 and C4N4) or monomorphic (C3N1, C4N6, C4N2, C4N5, C4N8), based on studies of Caucasian, Asian, American Black and African Black populations. Our approach is based upon: (1) PCR amplification using primers directed to the sequences that flank the site of insertion of the different Alu elements studied; (2) gel electrophoresis and scoring according to the presence or absence of an Alu insertion in one or both homologous chromosomes; (3) allelic frequencies calculated and compared according to Hardy-Weinberg equilibrium. Our DNA fingerprinting procedure using PCR amplification of dimorphic Human Specific Alu insertions, is stable enough to be used not only as a tool for genetic mapping but also to characterize populations, study migrational patterns and track the inheritance of human genetic disorders.
Date: December 4, 1992
Creator: Novick, G. E.; Gonzalez, T.; Garrison, J.; Novick, C. C.; Herrera, R. J.; Batzer, M. A. et al.
System: The UNT Digital Library
A Numerical Algorithm for the Solution of a Phase-Field Model of Polycrystalline Materials (open access)

A Numerical Algorithm for the Solution of a Phase-Field Model of Polycrystalline Materials

We describe an algorithm for the numerical solution of a phase-field model (PFM) of microstructure evolution in polycrystalline materials. The PFM system of equations includes a local order parameter, a quaternion representation of local orientation and a species composition parameter. The algorithm is based on the implicit integration of a semidiscretization of the PFM system using a backward difference formula (BDF) temporal discretization combined with a Newton-Krylov algorithm to solve the nonlinear system at each time step. The BDF algorithm is combined with a coordinate projection method to maintain quaternion unit length, which is related to an important solution invariant. A key element of the Newton-Krylov algorithm is the selection of a preconditioner to accelerate the convergence of the Generalized Minimum Residual algorithm used to solve the Jacobian linear system in each Newton step. Results are presented for the application of the algorithm to 2D and 3D examples.
Date: December 4, 2008
Creator: Dorr, M R; Fattebert, J; Wickett, M E; Belak, J F & Turchi, P A
System: The UNT Digital Library
NANOSTRUCTURED METAL OXIDES FOR ANODES OF LI-ION RECHARGEABLE BATTERIES (open access)

NANOSTRUCTURED METAL OXIDES FOR ANODES OF LI-ION RECHARGEABLE BATTERIES

The aligned nanorods of Co{sub 3}O{sub 4} and nanoporous hollow spheres (NHS) of SnO{sub 2} and Mn{sub 2}O{sub 3} were investigated as the anodes for Li-ion rechargeable batteries. The Co{sub 3}O{sub 4} nanorods demonstrated 1433 mAh/g reversible capacity. The NHS of SnO{sub 2} and Mn{sub 2}O{sub 3} delivered 400 mAh/g and 250 mAh/g capacities respectively in multiple galvonastatic discharge-charge cycles. It was found that high capacity of NHS of metal oxides is sustainable attributed to their unique structure that maintains material integrity during cycling. The nanostructured metal oxides exhibit great potential as the new anode materials for Li-ion rechargeable batteries with high energy density, low cost and inherent safety.
Date: December 4, 2009
Creator: Au, M.
System: The UNT Digital Library
Durable Glass for Thousands of Years (open access)

Durable Glass for Thousands of Years

The durability of natural glasses on geological time scales and ancient glasses for thousands of years is well documented. The necessity to predict the durability of high level nuclear waste (HLW) glasses on extended time scales has led to various thermodynamic and kinetic approaches. Advances in the measurement of medium range order (MRO) in glasses has led to the understanding that the molecular structure of a glass, and thus the glass composition, controls the glass durability by establishing the distribution of ion exchange sites, hydrolysis sites, and the access of water to those sites. During the early stages of glass dissolution, a 'gel' layer resembling a membrane forms through which ions exchange between the glass and the leachant. The hydrated gel layer exhibits acid/base properties which are manifested as the pH dependence of the thickness and nature of the gel layer. The gel layer ages into clay or zeolite minerals by Ostwald ripening. Zeolite mineral assemblages (higher pH and Al{sup 3+} rich glasses) may cause the dissolution rate to increase which is undesirable for long-term performance of glass in the environment. Thermodynamic and structural approaches to the prediction of glass durability are compared versus Ostwald ripening.
Date: December 4, 2009
Creator: Jantzen, Carol M.; Brown, Kevin G. & Pickett, J. B.
System: The UNT Digital Library