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TEMPERATURE PREDICTION IN 3013 CONTAINERS IN K AREA MATERIAL STORAGE (KAMS) FACILITY USING REGRESSION METHODS
3013 containers are designed in accordance with the DOE-STD-3013-2004. These containers are qualified to store plutonium (Pu) bearing materials such as PuO2 for 50 years. DOT shipping packages such as the 9975 are used to store the 3013 containers in the K-Area Material Storage (KAMS) facility at Savannah River Site (SRS). DOE-STD-3013-2004 requires that a comprehensive surveillance program be set up to ensure that the 3013 container design parameters are not violated during the long term storage. To ensure structural integrity of the 3013 containers, thermal analyses using finite element models were performed to predict the contents and component temperatures for different but well defined parameters such as storage ambient temperature, PuO{sub 2} density, fill heights, weights, and thermal loading. Interpolation is normally used to calculate temperatures if the actual parameter values are different from the analyzed values. A statistical analysis technique using regression methods is proposed to develop simple polynomial relations to predict temperatures for the actual parameter values found in the containers. The analysis shows that regression analysis is a powerful tool to develop simple relations to assess component temperatures.
Date:
April 22, 2008
Creator:
Gupta, N
Object Type:
Article
System:
The UNT Digital Library
Real-time X-ray Diffraction Measurements of Shocked Polycrystalline Tin and Aluminum
A new, fast, single-pulse x-ray diffraction (XRD) diagnostic for determining phase transitions in shocked polycrystalline materials has been developed. The diagnostic consists of a 37-stage Marx bank high-voltage pulse generator coupled to a needle-and-washer electron beam diode via coaxial cable, producing line and bremsstrahlung x-ray emission in a 35-ns pulse. The characteristic Kα lines from the selected anodes of silver and molybdenum are used to produce the diffraction patterns, with thin foil filters employed to remove the characteristic Kβ line emission. The x-ray beam passes through a pinhole collimator and is incident on the sample with an approximately 3-mm by 6-mm spot and 1° full-width-half-maximum (FWHM) angular divergence in a Bragg-reflecting geometry. For the experiments described in this report, the angle between the incident beam and the sample surface was 8.5°. A Debye-Scherrer diffraction image was produced on a phosphor located 76 mm from the polycrystalline sample surface. The phosphor image was coupled to a charge-coupled device (CCD) camera through a coherent fiberoptic bundle. Dynamic single-pulse XRD experiments were conducted with thin foil samples of tin, shock loaded with a 1-mm vitreous carbon back window. Detasheet high explosive with a 2-mm-thick aluminum buffer was used to shock the sample. Analysis …
Date:
November 22, 2008
Creator:
Dane V. Morgan, Don Macy, Gerald Stevens
Object Type:
Article
System:
The UNT Digital Library
Seismic stimulation for enhanced oil recovery
The pore-scale effects of seismic stimulation on two-phase flow are modeled numerically in random 2D grain0pack geometries. Seismic stimulation aims to enhance oil production by sending seismic waves across a reservoir to liberate immobile patches of oil. For seismic amplitudes above a well-defined (analytically expressed) dimensionless criterion, the force perturbation associated with the waves indeed can liberate oil trapped on capillary barriers and get it flowing again under the background pressure gradient. Subsequent coalescence of the freed oil droplets acts to enhance oil movement further because longer bubbles overcome capillary barriers more efficiently than shorter bubbles do. Poroelasticity theory defines the effective force that a seismic wave adds to the background fluid-pressure gradient. The lattice-Boltzmann model in two dimensions is used to perform pore-scale numerical simulations. Dimensionless numbers (groups of material and force parameters) involved in seismic stimulation are defined carefully so that numerical simulations can be applied to field-scale conditions. Using the analytical criteria defined in the paper, there is a significant range of reservoir conditions over which seismic stimulation can be expected to enhance oil production.
Date:
July 22, 2008
Creator:
Pride, S. R.; Flekkoy, E. G. & Aursjo, O.
Object Type:
Article
System:
The UNT Digital Library
Electronic Properties of Hydrogen Storage Materials with Photon-in/Photon-out Soft-X-Ray Spectroscopy
The applications of resonant soft X-ray emission spectroscopy on a variety of carbon systems have yielded characteristic fingerprints. With high-resolution monochromatized synchrotron radiation excitation, resonant inelastic X-ray scattering has emerged as a new source of information about electronic structure and excitation dynamics. Photon-in/photon-out soft-X-ray spectroscopy is used to study the electronic properties of fundamental materials, nanostructure, and complex hydrides and will offer potential in-depth understanding of chemisorption and/or physisorption mechanisms of hydrogen adsorption/desorption capacity and kinetics.
Date:
September 22, 2008
Creator:
Guo, Jinghua
Object Type:
Article
System:
The UNT Digital Library
RESULTS OF EXPERIMENT TO DETERMINE CORROSION RATES FOR 304L IN HB-LINE DISSOLVER VESSEL VENTILATION SYSTEM
Radioactive material being processed as part of the DE3013 program for HB-Line will result in the presence of chlorides, and in some cases fluorides, in the dissolver. Material Science and Technology developed an experimental plan to evaluate the impact of chloride on corrosion of the dissolver vessel ventilation system. The plan set test variables from the proposed operating parameters, previous test results, and a desired maximum chloride concentration for processing. The test variables included concentrations of nitric acid, fluorides and chlorides, and the presence of a welded and stressed metal coupon. Table 1 contains expected general corrosion rates in the HB-Line vessel vent system from dissolution of 3013 contents of varying nitric acid and chloride content. These general corrosion rates were measured upstream of the condenser in the experiment's offgas system near the entrance to the dissolver. However, they could apply elsewhere in the offgas system, depending on factors not simulated in the testing, including offgas system temperatures and airflow. Localized corrosion was significant in Tests One, Two, and Three. This corrosion is significant because it will probably be the first mode of penetration of the 304L steel in several places in the system. See Table 2. For Tests One …
Date:
February 22, 2008
Creator:
Mickalonis, J & Kathryn Counts, K
Object Type:
Report
System:
The UNT Digital Library
Laser Tracker Test Facility at SLAC - Progress Report
Physics experiments at SLAC require high accuracy positioning, e. g. 100 {micro}m over a distance of 150 m or 25 {micro}m in a 10 x 10 x 3 meter volume. Laser Tracker measurement systems have become one of the most important tools for achieving these accuracies when mapping components. In order to improve and get a better understanding of laser tracker measurement tolerances we extended our laboratory with a rotary calibration table (Kugler GmbH) providing an accuracy of better than 0.2 arcsec. This paper gives an overview of the calibration table and its evaluation. Results of tests on two of our Laser Trackers utilizing the new rotary table as well as the SLAC interferometer bench are presented.
Date:
February 22, 2008
Creator:
Gassner, G. L. & Ruland, R. E.
Object Type:
Article
System:
The UNT Digital Library
High-Level Application Framework for LCLS
A framework for high level accelerator application software is being developed for the Linac Coherent Light Source (LCLS). The framework is based on plug-in technology developed by an open source project, Eclipse. Many existing functionalities provided by Eclipse are available to high-level applications written within this framework. The framework also contains static data storage configuration and dynamic data connectivity. Because the framework is Eclipse-based, it is highly compatible with any other Eclipse plug-ins. The entire infrastructure of the software framework will be presented. Planned applications and plug-ins based on the framework are also presented.
Date:
April 22, 2008
Creator:
Chu, P; Chevtsov, S.; Fairley, D.; Larrieu, C.; Rock, J.; Rogind, D. et al.
Object Type:
Article
System:
The UNT Digital Library
Nanowires, Capacitors, and Other Novel Outer-Surface Components Involved in Electron Transfer to Fe(III) Oxides in Geobacter Species
The overall goal of this project was to better understand the mechanisms by which Geobacter species transfer electrons outside the cell onto Fe(III) oxides. The rationale for this study was that Geobacter species are often the predominant microorganisms involved in in situ uranium bioremediation and the growth and activity of the Geobacter species during bioremediation is primarily supported by electron transfer to Fe(III) oxides. These studies greatly expanded the understanding of electron transfer to Fe(III). Novel concepts developed included the potential role of microbial nanowires for long range electron transfer in Geobacter species and the importance of extracytoplasmic cytochromes functioning as capacitors to permit continued electron transfer during the hunt for Fe(III) oxide. Furthermore, these studies provided target sequences that were then used in other studies to tract the activity of Geobacter species in the subsurface through monitoring the abundance of gene transcripts of the target genes. A brief summary of the major accomplishments of the project is provided.
Date:
December 22, 2008
Creator:
Lovley, Derek, R.
Object Type:
Report
System:
The UNT Digital Library
Wet Gasification of Ethanol Residue: A Preliminary Assessment
A preliminary technoeconomic assessment has been made of several options for the application of catalytic hydrothermal gasification (wet gasification) to ethanol processing residues.
Date:
September 22, 2008
Creator:
Brown, Michael D. & Elliott, Douglas C.
Object Type:
Report
System:
The UNT Digital Library
CHARACTERIZATION OF SAMPLES FROM TANK 16H ANNULUS
In support of the closure of Tank 16H, the remaining waste material in the tank annulus must be removed. Samples of the waste material from Tank 16H annulus were obtained and sent to Savannah River National Laboratory (SRNL) to determine the chemical and radiochemical composition prior to further waste removal. The three samples obtained from the Tank 16H annulus show some similarity as to the types of mineral phases present in the materials but differ in the relative amounts of each phase present. The samples from outside the dehumidification duct at two locations in the annulus show very different compositions and estimated solubility in water. This indicates the waste material in Tank 16H annulus may have a wide range of compositions at different locations. The table below provides a simplified description of the composition of each sample. The limited characterization techniques conducted and the complex mixture of materials in each sample makes assigning a definitive composition for each sample difficult. Given the variability in composition with just the three small samples characterized, a more detailed description of any single sample may be of limited value.
Date:
May 22, 2008
Creator:
Hay, M
Object Type:
Report
System:
The UNT Digital Library
12.6 keV Kr K-alpha X-ray Source For High Energy Density Physics Experiments
A high contrast 12.6 keV Kr K{alpha} source has been demonstrated on the petawatt-class Titan laser facility. The contrast ratio (K{alpha} to continuum) is 65, with a competitive ultra short pulse laser to x-ray conversion efficiency of 10{sup -5}. Filtered shadowgraphy indicates that the Kr K{alpha} and K{beta} x-rays are emitted from a roughly 1 x 2 mm emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e. mean ionization state 13-16), based on the observed ratio of K{alpha} to K{beta}. Kr gas jets provide a debris-free high energy K{alpha} source for time-resolved diagnosis of dense matter.
Date:
April 22, 2008
Creator:
Kugland, N.; Constantin, C. G.; Niemann, C.; Neumayer, P.; Chung, H.; Doppner, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Conduct of Operations Applicability Matrix for CMELS Low Hazard Facilities at LLNL Site 200
None
Date:
April 22, 2008
Creator:
Cooper, G A
Object Type:
Report
System:
The UNT Digital Library
Interaction Region Upgrades of e+ e- B-Factories
Both the PEP-II and KEKB B-Factories have plans to upgrade their Interaction Regions (IRs) in order to improve luminosity performance. Last summer PEP-II added cooling to the IR beam pipe in order to increase beam currents thereby raising the luminosity. In addition, PEP-II is working on a design that modifies the permanent magnets near the Interaction Point (IP) for an even higher luminosity increase. KEKB is also planning an improvement to their IR that will decrease the detector beam pipe radius. In addition, KEK has a design to increase the luminosity of KEKB to 1 x 10{sup 35} cm{sup -2} sec{sup -1} which includes changes to the IR. PEP-II is also investigating the feasibility of a 1 x 10{sup 36} cm{sup -2} sec{sup -1} luminosity design. I summarize these various upgrades and concentrate on issues common to the different designs.
Date:
February 22, 2008
Creator:
Sullivan, M.
Object Type:
Article
System:
The UNT Digital Library
Letter Report for Waste Disposal Activities for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks, Nevada Test Site, Nevada, March 2008
None
Date:
April 22, 2008
Creator:
National Security Technologies, LLC
Object Type:
Report
System:
The UNT Digital Library
High Performance Multivariate Visual Data Exploration for Extremely Large Data
One of the central challenges in modern science is the need to quickly derive knowledge and understanding from large, complex collections of data. We present a new approach that deals with this challenge by combining and extending techniques from high performance visual data analysis and scientific data management. This approach is demonstrated within the context of gaining insight from complex, time-varying datasets produced by a laser wakefield accelerator simulation. Our approach leverages histogram-based parallel coordinates for both visual information display as well as a vehicle for guiding a data mining operation. Data extraction and subsetting are implemented with state-of-the-art index/query technology. This approach, while applied here to accelerator science, is generally applicable to a broad set of science applications, and is implemented in a production-quality visual data analysis infrastructure. We conduct a detailed performance analysis and demonstrate good scalability on a distributed memory Cray XT4 system.
Date:
August 22, 2008
Creator:
Rubel, Oliver; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R.; Cormier-Michel, Estelle et al.
Object Type:
Article
System:
The UNT Digital Library
A high-throughput contact-hole resolution metric for photoresists: Full-process sensitivity study
None
Date:
January 22, 2008
Creator:
Anderson, Christopher & Jones, Juanita
Object Type:
Article
System:
The UNT Digital Library
Constructing QCD one-loop amplitudes
In the context of constructing one-loop amplitudes using a unitarity bootstrap approach we discuss a general systematic procedure for obtaining the coefficients of the scalar bubble and triangle integral functions of one-loop amplitudes. Coefficients are extracted after examining the behavior of the cut integrand as the unconstrained parameters of a specifically chosen parameterization of the cut loop momentum approach infinity. Measurements of new physics at the forthcoming experimental program at CERN's Large Hadron Collider (LHC) will require a precise understanding of processes at next-to-leading order (NLO). This places increased demands for the computation of new one-loop amplitudes. This in turn has spurred recent developments towards improved calculational techniques. Direct calculations using Feynman diagrams are in general inefficient. Developments of more efficient techniques have usually centered around unitarity techniques [1], where tree amplitudes are effectively 'glued' together to form loops. The most straightforward application of this method, in which the cut loop momentum is in D = 4, allows for the computation of 'cut-constructible' terms only, i.e. (poly)logarithmic containing terms and any related constants. QCD amplitudes contain, in addition to such terms, rational pieces which cannot be derived using such cuts. These 'missing' rational parts can be extracted using cut loop …
Date:
February 22, 2008
Creator:
Forde, Darren
Object Type:
Article
System:
The UNT Digital Library
BIOASSAY VESSEL FAILURE ANALYSIS
Two high-pressure bioassay vessels failed at the Savannah River Site during a microwave heating process for biosample testing. Improper installation of the thermal shield in the first failure caused the vessel to burst during microwave heating. The second vessel failure is attributed to overpressurization during a test run. Vessel failure appeared to initiate in the mold parting line, the thinnest cross-section of the octagonal vessel. No material flaws were found in the vessel that would impair its structural performance. Content weight should be minimized to reduce operating temperature and pressure. Outer vessel life is dependent on actual temperature exposure. Since thermal aging of the vessels can be detrimental to their performance, it was recommended that the vessels be used for a limited number of cycles to be determined by additional testing.
Date:
September 22, 2008
Creator:
Vormelker, P
Object Type:
Article
System:
The UNT Digital Library
Enantioselective Intramolecular Hydroarylation of Alkenes via Directed C-H Bond Activation
Highly enantioselective catalytic intramolecular ortho-alkylation of aromatic imines containing alkenyl groups tethered at the meta position relative to the imine directing group has been achieved using [RhCl(coe){sub 2}]{sub 2} and chiral phosphoramidite ligands. Cyclization of substrates containing 1,1- and 1,2-disubstituted as well as trisubstituted alkenes were achieved with enantioselectivities >90% ee for each substrate class. Cyclization of substrates with Z-alkene isomers proceeded much more efficiently than substrates with E-alkene isomers. This further enabled the highly stereoselective intramolecular alkylation of certain substrates containing Z/E-alkene mixtures via a Rh-catalyzed alkene isomerization with preferential cyclization of the Z-isomer.
Date:
May 22, 2008
Creator:
Harada, Hitoshi; Thalji, Reema; Bergman, Robert & Ellman, Jonathan
Object Type:
Article
System:
The UNT Digital Library
NUCLEAR POWERED CO2 CAPTURE FROM THE ATMOSPHERE
A process for capturing CO{sub 2} from the atmosphere was recently proposed. This process uses a closed cycle of sodium and calcium hydroxide, carbonate, and oxide transformations to capture dilute CO{sub 2} from the atmosphere and to generate a concentrated stream of CO{sub 2} that is amenable to sequestration or subsequent chemical transformations. In one of the process steps, a fossil-fueled lime kiln is needed, which reduces the net CO{sub 2} capture of the process. It is proposed to replace the fossil-fueled lime kiln with a modified kiln heated by a high-temperature nuclear reactor. This will have the effect of eliminating the use of fossil fuels for the process and increasing the net CO{sub 2} capture. Although the process is suitable to support sequestration, the use of a nuclear power source for the process provides additional capabilities, and the captured CO{sub 2} may be combined with nuclear-produced hydrogen to produce liquid fuels via Fischer-Tropsch synthesis or other technologies. Conceivably, such plants would be carbon-neutral, and could be placed virtually anywhere without being tied to fossil fuel sources or geological sequestration sites.
Date:
September 22, 2008
Creator:
Sherman, S
Object Type:
Article
System:
The UNT Digital Library
Towards a Real-time Transient Classification Engine
Temporal sampling does more than add another axis to the vector of observables. Instead, under the recognition that how objects change (and move) in time speaks directly to the physics underlying astronomical phenomena, next-generation wide-field synoptic surveys are poised to revolutionize our understanding of just about anything that goes bump in the night (which is just about everything at some level). Still, even the most ambitious surveys will require targeted spectroscopic follow-up to fill in the physical details of newly discovered transients. We are now building a new system intended to ingest and classify transient phenomena in near real-time from high-throughput imaging data streams. Described herein, the Transient Classification Project at Berkeley will be making use of classification techniques operating on"features" extracted from time series and contextual (static) information. We also highlight the need for a community adoption of a standard representation of astronomical time series data (i.e.,"VOTimeseries").
Date:
February 22, 2008
Creator:
Nugent, Peter E.; Bloom, Josh; Starr, Dan; Butler, Nat; Nugent, Peter; Rischard, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 133, Ed. 1 Tuesday, April 22, 2008
Free weekly newspaper that includes business and classified advertising.
Date:
April 22, 2008
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 39, No. 289, Ed. 1 Tuesday, July 22, 2008
Free weekly newspaper that includes business and classified advertising.
Date:
July 22, 2008
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 602, Ed. 1 Tuesday, January 22, 2008
Free weekly newspaper that includes business and classified advertising.
Date:
January 22, 2008
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History