Advanced /sup 90/Sr space power supply. 250 watt dynamic system (open access)

Advanced /sup 90/Sr space power supply. 250 watt dynamic system

None
Date: September 6, 1973
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Shiva automatic alignment systems: a brief description (open access)

Shiva automatic alignment systems: a brief description

A diagram is given of the basic Shiva alignment system. The alignment requirements, as originally specified and as preseently estimated, together with the performance obtained to date from the prototype equipment are described. It is expected that this performance will be satisfactory for even the most alignment-sensitive targets and significantly better than is needed for experiments not requiring highly uniform illumination. The hardware arrangement planned for a typical Shiva chain is shown.
Date: September 6, 1977
Creator: Bliss, E. S.; Summers, M. A.; Cody, R. L.; Boyd, R. D. & Wintemute, J. D.
Object Type: Report
System: The UNT Digital Library
Advanced /sup 90/Sr space power supply. 250 watt static system (open access)

Advanced /sup 90/Sr space power supply. 250 watt static system

None
Date: September 6, 1973
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Thulium-170 heat source (open access)

Thulium-170 heat source

An isotopic heat source is formed using stacks of thin individual layers of a refractory isotopic fuel, preferably thulium oxide, alternating with layers of a low atomic weight diluent, preferably graphite. The graphite serves several functions: to act as a moderator during neutron irradiation, to minimize bremsstrahlung radiation, and to facilitate heat transfer. The fuel stacks are inserted into a heat block, which is encased in a sealed, insulated and shielded structural container. Heat pipes are inserted in the heat block and contain a working fluid. The heat pipe working fluid transfers heat from the heat block to a heat exchanger for power conversion. Single phase gas pressure controls the flow of the working fluid for maximum heat exchange and to provide passive cooling.
Date: September 6, 1990
Creator: Walter, Carl E.; Van Konynenburg, Richard & VanSant, James H.
Object Type: Report
System: The UNT Digital Library
Small power plant reverse trade mission (open access)

Small power plant reverse trade mission

This draft report was prepared as required by Task No. 2 of the US Department of Energy, Grant No. FG07-89ID12850 Reverse Trade Mission to Acquaint International Representatives with US Power Plant and Drilling Technology'' (mission). As described in the grant proposal, this report covers the reactions of attendees toward US technology, its possible use in their countries, and an evaluation of the mission by the staff leaders. Note this is the draft report of one of two missions carried out under the same contract number. Because of the diversity of the mission subjects and the different attendees at each, a separate report for each mission has been prepared. This draft report has been sent to all mission attendees, specific persons in the US Department of Energy and Los Alamos National Lab., the California Energy Commission (CEC), and various other governmental agencies.
Date: September 6, 1989
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Development of a building wake/stack height numerical modeling capability (open access)

Development of a building wake/stack height numerical modeling capability

We are developing state-of-the-art numerical tools which can be used to provide reliable estimates of potential emissions at various LLNL sites. In particular we have focused our efforts in generating models which can simulate the wind flow and dispersion of airborne pollutants around surface-mounted structures such as buildings or building complexes. To achieve this goal, we have adopted two different but complementary approaches in the modeling of this complex problem. The first approach employs a Reynolds-averaged set of equations whose solution results in a description of the mean flow and concentration pattern. In the second approach, we are developing a more advanced model based on the large eddy simulation (LES) concept. In this report, we describe the progress in the development of the two approaches. We begin by discussing the calculational procedure which has been chosen for the Reynolds-averaged model, namely: prediction of the mean flow via a turbulent flow model, and; employment of the calculated flow field to drive a particle-in-cell transport and diffusion model (ADPIC). The performance of this model is benchmarked against experimental data obtained for flow over a backward-facing step. The backward-facing step problem can be viewed as a simplification of a rectangular-shaped surface mounted obstacle. …
Date: September 6, 1991
Creator: Lee, R.L. & McCallen, R.C.
Object Type: Report
System: The UNT Digital Library
An Update on the Status of the NIF Power Conditioning System (open access)

An Update on the Status of the NIF Power Conditioning System

The National Ignition Facility (NIF) Power Conditioning System provides the pulsed excitation required to drive flashlamps in the laser's optical amplifiers. Modular in design, each of the 192 Main Energy Storage Modules (MESMs) stores up to 2.2 MJ of electrical energy in its capacitor bank before delivering the energy to 20 pairs of flashlamps in a 400 {micro}s pulse (10% power points). The peak current of each MESM discharge is 0.5 MA. Production, installation, commissioning and operation of the NIF Power Conditioning continue to progress rapidly, with the goals of completing accelerated production and commissioning by early 2008, while maintaining an aggressive operation schedule. To date, more than 97% of the required modules have been assembled, shipped and installed in the facility, representing more that 380 MJ of stored energy available for driving NIF flashlamps. The MESMs have displayed outstanding reliability during daily, multiple-shift operations.
Date: September 6, 2007
Creator: Arnold, P. A.; Hulsey, S.; Ullery, G. T.; Petersen, D. E.; Pendleton, D. L.; Ollis, C. W. et al.
Object Type: Article
System: The UNT Digital Library
Authentication Assurance Level Application to the Inventory Sampling Measurement System (open access)

Authentication Assurance Level Application to the Inventory Sampling Measurement System

This document concentrates on the identification of a standardized assessment approach for the verification of security functionality in specific equipment, the Inspection Sampling Measurement System (ISMS) being developed for MAYAK. Specifically, an Authentication Assurance Level 3 is proposed to be reached in authenticating the ISMS.
Date: September 6, 2001
Creator: Devaney, Mike M.; Kouzes, Richard T.; Hansen, Randy R. & Geelhood, Bruce D.
Object Type: Report
System: The UNT Digital Library
Application of Argonne's Glass Furnace Model to Longhor Glass Corporation Oxy-Fuel Furnace for the Production of Amber Glass. (open access)

Application of Argonne's Glass Furnace Model to Longhor Glass Corporation Oxy-Fuel Furnace for the Production of Amber Glass.

The objective of this project is to apply the Argonne National Laboratory's Glass Furnace Model (GFM) to the Longhorn oxy-fuel furnace to improve energy efficiency and to investigate the transport of gases released from the batch/melt into the exhaust. The model will make preliminary estimates of the local concentrations of water, carbon dioxide, elemental oxygen, and other subspecies in the entire combustion space as well as the concentration of these species in the furnace exhaust gas. This information, along with the computed temperature distribution in the combustion space may give indications on possible locations of crown corrosion. An investigation into the optimization of the furnace will be performed by varying several key parameters such as the burner firing pattern, exhaust number/size, and the boost usage (amount and distribution). Results from these parametric studies will be analyzed to determine more efficient methods of operating the furnace that reduce crown corrosion. Finally, computed results from the GFM will be qualitatively correlated to measured values, thus augmenting the validation of the GFM.
Date: September 6, 2006
Creator: Golchert, B.; Shell, J.; Jones, S.; Systems, Energy; Consulting, Shell Glass & Group, Anheuser-Busch Packaging
Object Type: Report
System: The UNT Digital Library
Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report. (open access)

Atmospheric Radiation Measurement Program Climate Research Facility Operations Quarterly Report.

Individual raw data streams from instrumentation at the Atmospheric Radiation Measurement (ARM) Program Climate Research Facility (ACRF) fixed and mobile sites are collected and sent to the Data Management Facility (DMF) at Pacific Northwest National Laboratory (PNNL) for processing in near real time. Raw and processed data are then sent daily to the ACRF Archive, where they are made available to users. For each instrument, we calculate the ratio of the actual number of data records received daily at the Archive to the expected number of data records. The results are tabulated by (1) individual data stream, site, and month for the current year and (2) site and fiscal year dating back to 1998. The U.S. Department of Energy requires national user facilities to report time-based operating data. The requirements concern the actual hours of operation (ACTUAL); the estimated maximum operation or uptime goal (OPSMAX), which accounts for planned downtime; and the VARIANCE [1-(ACTUAL/OPSMAX)], which accounts for unplanned downtime. The OPSMAX time for the third quarter for the Southern Great Plains (SGP) site is 2,074.80 hours (0.95 x 2,184 hours this quarter). The OPSMAX for the North Slope Alaska (NSA) locale is 1,965.60 hours (0.90 x 2,184), and that for …
Date: September 6, 2006
Creator: Sisterson, D. L. & Sciences, Decision and Information
Object Type: Report
System: The UNT Digital Library
More visible effects of the hidden sector (open access)

More visible effects of the hidden sector

There is a growing appreciation that hidden sector dynamics may affect the supersymmetry breaking parameters in the visible sector (supersymmetric standard model), especially when the dynamics is strong and superconformal. We point out that there are effects that have not been previously discussed in the literature. For example, the gaugino masses are suppressed relative to the gravitino mass. We discuss their implications in the context of various mediation mechanisms. The issues discussed include anomaly mediation with singlets, the mu (B mu) problem in gauge and gaugino mediation, and distinct mass spectra for the superparticles that have not been previously considered.
Date: September 6, 2007
Creator: Murayama, Hitoshi; Murayama, Hitoshi; Nomura, Yasunori & Poland, David
Object Type: Article
System: The UNT Digital Library
Atomistically-informed Dislocation Dynamics in fcc Crystals (open access)

Atomistically-informed Dislocation Dynamics in fcc Crystals

We develop a nodal dislocation dynamics (DD) model to simulate plastic processes in fcc crystals. The model explicitly accounts for all slip systems and Burgers vectors observed in fcc systems, including stacking faults and partial dislocations. We derive simple conservation rules that describe all partial dislocation interactions rigorously and allow us to model and quantify cross-slip processes, the structure and strength of dislocation junctions and the formation of fcc-specific structures such as stacking fault tetrahedra. The DD framework is built upon isotropic non-singular linear elasticity, and supports itself on information transmitted from the atomistic scale. In this fashion, connection between the meso and micro scales is attained self-consistently with core parameters fitted to atomistic data. We perform a series of targeted simulations to demonstrate the capabilities of the model, including dislocation reactions and dissociations and dislocation junction strength. Additionally we map the four-dimensional stress space relevant for cross-slip and relate our findings to the plastic behavior of monocrystalline fcc metals.
Date: September 6, 2006
Creator: Martinez, E.; Marian, J.; Arsenlis, T.; Victoria, M. & Perlado, J. M.
Object Type: Article
System: The UNT Digital Library
Recovery of Minerals and Metals from Geothermal Fluids (open access)

Recovery of Minerals and Metals from Geothermal Fluids

None
Date: September 6, 2005
Creator: Bourcier, W L; Lin, M & Nix, G
Object Type: Article
System: The UNT Digital Library
Californium Isotopes From Bombardment of Uranium With Carbonions (open access)

Californium Isotopes From Bombardment of Uranium With Carbonions

The recent production and identification of isotopes of elements with atomic numbers up to six higher than the target element through bombardment with hexapositive 120-Mev carbon ions made it seem worthwhile to apply this technique to the transuranium region. Accordingly, small pieces of natural uranium metal (about 0.5 mil thick and 205 cm by 0.6 cm area) were irradiated in the internal carbon ion beam in the Berkeley 60-inch cyclotron. Following the irradiations, the uranium was dissolved in dilute hydrochloric acid containing hydrogen peroxide and a transplutonium fraction was isolated through the use of lanthanum fluoride, and lanthanum hydroxide precipitation steps followed by the ion exchange adsorption column procedure in which concentrated hydrochloric acid is used to separate the tripositive actinide elements from the rare earth elements. The transplutonium fractions in hydrochloric acid were evaporated as weightless films on platinum plates which were placed in the ionization chamber of the 48 channel pulse analyzer apparatus in order to measure the yield and energies of any alpha-particles which might be present. In the best experiment at about one hour after the end of the 90-minute bombardment, some 50 disintegrations per minute of the distinctive 7.1-Mev alpha-particles of Cf{sup 244} were observed …
Date: September 6, 1950
Creator: Ghiorso, A.; Thompson, S. G.; Street, Jr., K. & Seaborg, G. T.
Object Type: Report
System: The UNT Digital Library
An atomic force microcopy study of the mechanical and electricalproperties of monolayer films of molecules with aromatic end groups (open access)

An atomic force microcopy study of the mechanical and electricalproperties of monolayer films of molecules with aromatic end groups

The effect of intermolecular {pi}-{pi} stacking on the electrical and mechanical properties of monolayer films molecules containing aromatic groups was studied using atomic force microscopy. Two types of aromatic molecules, (4-mercaptophenyl) anthrylacetylene (MPAA) and (4-mercaptophenyl)-phenylacetylene (MPPA) were used as model systems with different {pi}-{pi} stacking strength. Monolayer films of these molecules on Au(111) surfaces exhibited conductivities differing by more than one order of magnitude, MPAA being the most conductive and MPPA the least conductive. The response to compressive loads by the AFM tip was also found to be very different for both molecules. In MPAA films distinct molecular conductivity changes are observed upon mechanical perturbation. This effect however was not observed on the MPPA film, where intermolecular {pi}-{pi} interactions are likely weaker.
Date: September 6, 2007
Creator: Fang, Liang; Park, J.Y.; Ma, H.; Jen, A.K.-Y. & Salmeron, M.
Object Type: Article
System: The UNT Digital Library
Interaction of Nocturnal Low-Level Jets with Urban Geometries as seen in Joint URBAN 2003 Data (open access)

Interaction of Nocturnal Low-Level Jets with Urban Geometries as seen in Joint URBAN 2003 Data

As accurate modeling of atmospheric flows in urban environments requires sophisticated representation of complex urban geometries, much work has been devoted to treatment of the urban surface. However, the importance of the larger-scale flow impinging upon the urban complex to the flow, transport and dispersion within it and downwind has received less attention. Building-resolving computational fluid dynamics (CFD) models are commonly employed to investigate interactions between the flow and three-dimensional structures comprising the urban environment, however such models are typically forced with simplified boundary conditions that fail to include important regional-scale phenomena that can strongly influence the flow within the urban complex and downwind. This paper investigates the interaction of an important and frequently occurring regional-scale phenomenon, the nocturnal low-level jet (LLJ), with urban-scale turbulence and dispersion in Oklahoma City using data from the Joint URBAN 2003 (JU2003) field experiment. Two simulations of nocturnal tracer release experiments from JU2003 using Lawrence Livermore National laboratory's FEM3MP CFD model yield differing levels of agreement with the observations in wind speed, turbulence kinetic energy (TKE) and concentration profiles in the urban wake, approximately 750m downwind of the central business district. Profiles of several observed turbulence parameters at this location indicate characteristics of both …
Date: September 6, 2006
Creator: Lundquist, J. K. & Mirocha, J. D.
Object Type: Article
System: The UNT Digital Library
Geometric metastability, quivers and holography (open access)

Geometric metastability, quivers and holography

We use large N duality to study brane/anti-brane configurations on a class of Calabi-Yau manifolds. With only branes present, the Calabi-Yau manifolds in question give rise to N=2 ADE quiver theories deformed by superpotential terms. We show that the large N duality conjecture of hep-th/0610249 reproduces correctly the known qualitative features of the brane/anti-brane physics. In the supersymmetric case, the gauge theories have Seiberg dualities which are represented as flops in the geometry. Moreover, the holographic dual geometry encodes the whole RG flow of the gauge theory. In the non-supersymmetric case, the large N duality predicts that the brane/anti-brane theories also enjoy such dualities, and allows one to pick out the good description at a given energy scale.
Date: September 6, 2007
Creator: Aganagic, Mina; Aganagic, Mina; Beem, Christopher & Freivogel, Ben
Object Type: Article
System: The UNT Digital Library
Optical switching and contrast enhancement in intense laser systems by cascaded optical parametric amplification (open access)

Optical switching and contrast enhancement in intense laser systems by cascaded optical parametric amplification

Optical parametric chirped-pulse amplification (OPCPA) can be used to improve the prepulse contrast in chirped-pulse amplification systems by amplifying the main pulse with a total saturated OPCPA gain, while not affecting the preceding prepulses of the seed oscillator mode-locked pulse train. We show that a simple modification of a multistage OPCPA system into a cascaded optical parametric amplifier (COPA) results in an optical switch and extreme contrast enhancement which can completely eliminate the preceding and trailing oscillator pulses. Instrument-limited measurement of prepulse contrast ratio of 1.4 x 10{sup 11} is demonstrated from COPA at a 30-mJ level.
Date: September 6, 2005
Creator: Jovanovic, I; Haefner, C; Wattellier, B & Barty, C J
Object Type: Article
System: The UNT Digital Library
Summarizing my DHS Internship Experience (open access)

Summarizing my DHS Internship Experience

In this paper, the author addresses four main topics: (1) A description of the topic of his internship at the U.S. Department of Homeland Security; (2) A description of his contributions to the project; (3) A discussion of research directions beneficial to the Department of Homeland Security (DHS); and (4) A discussion of the impact the internship experience had on his career aspirations. He feels the first three points can best be addressed using the contents of a paper his mentor, Dr. Tina Eliassi-Rad, and he have published based on their work this summer [Roberts and Eliassi-Rad, 2006]. Sections 2 - 5 are intended for this purpose and have been excerpted from that paper. He concludes this paper in Section 6 with a discussion of the fourth point.
Date: September 6, 2006
Creator: Roberts, D L
Object Type: Report
System: The UNT Digital Library
Polychlorinated Biphenyl Presence in the Columbia River Corridor (open access)

Polychlorinated Biphenyl Presence in the Columbia River Corridor

The U. S. Department of Energy (DOE) is required by Comprehensive Environmental Response, Compensation, and Liability Act of 1980 regulations to develop a conceptual understanding of potential contaminant releases from the Hanford Site based on an evaluation of existing data and known historical practices. Polychlorinated biphenyls (PCBs) are one environmental contaminant potentially released through leaks, spills, or disposal. This document presents a summary of selected relevant existing information, including environmental studies and Hanford Site analytical data.
Date: September 6, 2007
Creator: Hermann, R. M.
Object Type: Report
System: The UNT Digital Library
PHYSICS DIV. QUARTERLY REPORT, MAY, JUNE, JULY, 1950 (open access)

PHYSICS DIV. QUARTERLY REPORT, MAY, JUNE, JULY, 1950

The X-ray Spectrum Produced by 322 Mev Electrons Striking a Platinum Target. The differential energy spectrum of the photons produced by 322 Mev electrons striking a 20 mil platinum target was measured by observing the energy of 3467 pairs produced in a one mil thick lead foil in a Wilson cloud chamber in a magnetic field of 10,000 gauss. The spectrum is found to agree with that predicted by the Bethe-Heitler bremsstrahlung theory using a Thomas-Fermi model with suitable corrections for the thickness of the target. The energy of the 322 Mev electrons was determined by the spectrum of the photons observed in this experiment. Apparatus used and the experimental data and results obtained are reported fully in UCRL-660.
Date: September 6, 1950
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Exploring Lifetime Effects in Femtoscopy (open access)

Exploring Lifetime Effects in Femtoscopy

We investigate the role of lifetime effects from resonances and emission duration tails in femtoscopy at RHIC in two Blast-Wave models. We find the non-Gaussian components compare well with published source imaged data, but the value of R{sub out} obtained from Gaussian fits is not insensitive to the non-Gaussian contributions when realistic acceptance cuts are applied to models.
Date: September 6, 2005
Creator: Brown, D.; Soltz, R.; Newby, J. & Kisiel, A.
Object Type: Article
System: The UNT Digital Library
Alignment validation (open access)

Alignment validation

The four experiments, ALICE, ATLAS, CMS and LHCb are currently under constructionat CERN. They will study the products of proton-proton collisions at the Large Hadron Collider. All experiments are equipped with sophisticated tracking systems, unprecedented in size and complexity. Full exploitation of both the inner detector andthe muon system requires an accurate alignment of all detector elements. Alignmentinformation is deduced from dedicated hardware alignment systems and the reconstruction of charged particles. However, the system is degenerate which means the data is insufficient to constrain all alignment degrees of freedom, so the techniques are prone to converging on wrong geometries. This deficiency necessitates validation and monitoring of the alignment. An exhaustive discussion of means to validate is subject to this document, including examples and plans from all four LHC experiments, as well as other high energy experiments.
Date: September 6, 2008
Creator: ALICE; ATLAS; CMS; LHCb & Golling, Tobias
Object Type: Article
System: The UNT Digital Library
Material dynamics under extreme conditions of pressure and strain rate (open access)

Material dynamics under extreme conditions of pressure and strain rate

Solid state experiments at extreme pressures (10-100 GPa) and strain rates ({approx}10{sup 6}-10{sup 8}s{sup -1}) are being developed on high-energy laser facilities, and offer the possibility for exploring new regimes of materials science. These extreme solid-state conditions can be accessed with either shock loading or with a quasi-isentropic ramped pressure drive. Velocity interferometer measurements establish the high pressure conditions. Constitutive models for solid-state strength under these conditions are tested by comparing 2D continuum simulations with experiments measuring perturbation growth due to the Rayleigh-Taylor instability in solid-state samples. Lattice compression, phase, and temperature are deduced from extended x-ray absorption fine structure (EXAFS) measurements, from which the shock-induced {alpha}-{omega} phase transition in Ti and the {alpha}-{var_epsilon} phase transition in Fe are inferred to occur on sub-nanosec time scales. Time resolved lattice response and phase can also be measured with dynamic x-ray diffraction measurements, where the elastic-plastic (1D-3D) lattice relaxation in shocked Cu is shown to occur promptly (< 1 ns). Subsequent large-scale molecular dynamics (MD) simulations elucidate the microscopic dynamics that underlie the 3D lattice relaxation. Deformation mechanisms are identified by examining the residual microstructure in recovered samples. The slip-twinning threshold in single-crystal Cu shocked along the [001] direction is shown to …
Date: September 6, 2005
Creator: Remington, Bruce A.; Allen, Patrick; Bringa, Eduaro; Hawreliak, Jim; Ho, Darwin; Lorenz, K. Thomas et al.
Object Type: Article
System: The UNT Digital Library