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Analysis of High Enriched Uranyl Nitrate Solution Containing Cadmium (open access)

Analysis of High Enriched Uranyl Nitrate Solution Containing Cadmium

A benchmark evaluation has been performed for a set of twenty-one critical experiments involving high enriched uranyl nitrate solution with and without cadmium nitrate as a soluble neutron absorber. The critical experiments analyzed include two types of cylindrical vessels with 24.18 and 29.16 cm in diameters. The vessels were reflected with water and in some cases with water containing dissolved cadmium nitrate. The uranium concentration ranged from 482 to 529 g/l, and cadmium concentration in the uranyl nitrate solution ranged from 0.0 to 11.31 g/l. The cadmium concentration in the reflector solution ranged from 0.0 to 15.16 g/l. Using MCNP and KENO-V.a, complete three-dimensional models were created for the two vessels filled with the uranyl nitrate solution and reflector solution. A series of criticality calculations were performed with KENO-V.a, MCNP4b, and MCNP5. In general, good agreement between KENO-V.a and MCNP4b was observed. However, MCNP5 results show consistently lower values compared with MCNP4b results with the maximum difference of 1.2 %. This ICSBEP supported evaluation provides valuable data for the effect of soluble neutron absorber (cadmium nitrate) on the criticality safety of high-enriched uranyl nitrate solution. These data can also be used in determining critical controls and for validation of the …
Date: September 1, 2006
Creator: Kim, S. S.
System: The UNT Digital Library
Architectural Visualization of C/C++ Source Code for Program Comprehension (open access)

Architectural Visualization of C/C++ Source Code for Program Comprehension

Structural and behavioral visualization of large-scale legacy systems to aid program comprehension is still a major challenge. The challenge is even greater when applications are implemented in flexible and expressive languages such as C and C++. In this paper, we consider visualization of static and dynamic aspects of large-scale scientific C/C++ applications. For our investigation, we reuse and integrate specialized analysis and visualization tools. Furthermore, we present a novel layout algorithm that permits a compressive architectural view of a large-scale software system. Our layout is unique in that it allows traditional program visualizations, i.e., graph structures, to be seen in relation to the application's file structure.
Date: September 1, 2006
Creator: Panas, T; Epperly, T W; Quinlan, D; Saebjornsen, A & Vuduc, R
System: The UNT Digital Library
Atmospheric Pressure Plasma Process And Applications (open access)

Atmospheric Pressure Plasma Process And Applications

This paper provides a general discussion of atmospheric-pressure plasma generation, processes, and applications. There are two distinct categories of atmospheric-pressure plasmas: thermal and nonthermal. Thermal atmospheric-pressure plasmas include those produced in high intensity arcs, plasma torches, or in high intensity, high frequency discharges. Although nonthermal plasmas are at room temperatures, they are extremely effective in producing activated species, e.g., free radicals and excited state atoms. Thus, both thermal and nonthermal atmosphericpressure plasmas are finding applications in a wide variety of industrial processes, e.g. waste destruction, material recovery, extractive metallurgy, powder synthesis, and energy conversion. A brief discussion of recent plasma technology research and development activities at the Idaho National Laboratory is included.
Date: September 1, 2006
Creator: Kong, Peter C. & Myrtle
System: The UNT Digital Library
B masses and lifetimes at the Tevatron (open access)

B masses and lifetimes at the Tevatron

The authors review recent results of B{sup ++} masses, mass and lifetime of B{sub c}{sup +} meson, and lifetimes of B{sub s}{sup 0} and {Lambda}{sub b}{sup 0} hadrons from Tevatron Run II.
Date: September 1, 2006
Creator: Uozumi, Satoru
System: The UNT Digital Library
Beam-Based Alignment of the NuMI Target Station Components at FNAL (open access)

Beam-Based Alignment of the NuMI Target Station Components at FNAL

The Neutrinos at the Main Injector (NuMI) facility is a conventional horn-focused neutrino beam which produces muon neutrinos from a beam of mesons directed into a long evacuated decay volume. The relative alignment of the primary proton beam, target, and focusing horns affects the neutrino energy spectrum delivered to experiments. This paper describes a check of the alignment of these components using the proton beam.
Date: September 1, 2006
Creator: Zwaska, R.; /Argonne; Bishai, M.; Childress, S.; Drake, G.; Escobar, C. et al.
System: The UNT Digital Library
Carbon dioxide capture and separation techniques for advanced power generation point sources (open access)

Carbon dioxide capture and separation techniques for advanced power generation point sources

The capture/separation step for carbon dioxide (CO2) from large-point sources is a critical one with respect to the technical feasibility and cost of the overall carbon sequestration scenario. For large-point sources, such as those found in power generation, the carbon dioxide capture techniques being investigated by the in-house research area of the National Energy Technology Laboratory possess the potential for improved efficiency and costs as compared to more conventional technologies. The investigated techniques can have wide applications, but the research has focused on capture/separation of carbon dioxide from flue gas (postcombustion from fossil fuel-fired combustors) and from fuel gas (precombustion, such as integrated gasification combined cycle – IGCC). With respect to fuel gas applications, novel concepts are being developed in wet scrubbing with physical absorption; chemical absorption with solid sorbents; and separation by membranes. In one concept, a wet scrubbing technique is being investigated that uses a physical solvent process to remove CO2 from fuel gas of an IGCC system at elevated temperature and pressure. The need to define an ideal solvent has led to the study of the solubility and mass transfer properties of various solvents. Fabrication techniques and mechanistic studies for hybrid membranes separating CO2 from the fuel …
Date: September 1, 2006
Creator: Pennline, Henry W.; Luebke, David R.; Morsi, Badie I.; Heintz, Yannick J.; Jones, Kenneth L. & Ilconich, Jeffery B.
System: The UNT Digital Library
CDF II detector and trigger for b physics (open access)

CDF II detector and trigger for b physics

In this paper the authors review the elements of the CDF detector and trigger most relevant for B physics analyses.
Date: September 1, 2006
Creator: Donati, S.
System: The UNT Digital Library
The CDF II eXtremely fast tracker upgrade (open access)

The CDF II eXtremely fast tracker upgrade

The CDF II Extremely Fast Tracker is the trigger track processor which reconstructs charged particle tracks in the transverse plane of the CDF II central outer tracking chamber. The system is now being upgraded to perform a three dimensional track reconstruction. A review of the upgrade is presented here.
Date: September 1, 2006
Creator: Abulencia, A.; Azzurri, P.; Cochran, E.; Dittmann, J.; Donati, S.; Efron, J. et al.
System: The UNT Digital Library
CDMS, Supersymmetry and Extra Dimensions (open access)

CDMS, Supersymmetry and Extra Dimensions

This report talks about CDMS, Supersymmetry and Extra Dimensions
Date: September 1, 2006
Creator: Akerib, D. S.; Attisha, M. J.; Bailey, C. N.; Baudis, Laura; Bauer, Daniel Adams; Brink, P. L. et al.
System: The UNT Digital Library
CLOSURE WELDING RADIOACTIVE MATERIALS CONTAINERS AT THE DEPARTMENT OF ENERGY (DOE) HANFORD SITE (open access)

CLOSURE WELDING RADIOACTIVE MATERIALS CONTAINERS AT THE DEPARTMENT OF ENERGY (DOE) HANFORD SITE

The Department of Energy's (DOE) responsibility for the disposition of radioactive materials has given rise to several unique welding applications. Many of these materials require packaging into containers for either Interim or long-term storage. It is not uncommon that final container fabrication, i.e., closure welding, is performed with these materials already placed into the container. Closure welding is typically performed remote to the container, and routine post-weld testing and nondestructive examination (NDE) are often times not feasible. Fluor Hanford has packaged many such materials in recent years as park of the Site's cleanup mission. In lieu of post-weld testing and NDE, the Fluor-Hanford approach has been to establish weld quality through ''upfront'' development and qualification of welding parameters, and then ensure parameter compliance during welding. This approach requires a rigor not usually afforded to typical welding development activities, and may involve statistical analysis and extensive testing, including burst, drop, sensitive leak testing, etc. This paper provides an instructive review of the development and qualification activities associated with the closure of radioactive materials containers, including a brief report on activities for closure welding research reactor, spent nuclear fuel (SNF) overpacks at the Hanford Site.
Date: September 1, 2006
Creator: CANNELL, G.R.
System: The UNT Digital Library
DAFNE Status Report (open access)

DAFNE Status Report

The operation of DAPHNE, the 1.02 GeV c.m. e{sup +}e{sup -} collider of the Frascati National Laboratory with the KLOE experimental detector was successfully concluded in March 2006. Since April 2004 it delivered a luminosity > 2 fb{sup -1} on the peak of the {Phi} resonance, > 0.25 fb{sup -1} off peak and a high statistics scan of the resonance. The best peak luminosity obtained during this run was 1.5 10{sup 32} cm{sup -2}s{sup -1}, while the maximum daily integrated luminosity was {approx}10 pb{sup -1}. The KLOE detector has been removed from one of the two interaction regions and its low beta section substituted with a standard magnetic structure allowing for an easy vertical separation of the beams, while the FINUDA detector has been moved onto the second interaction point. Several improvements on the rings have also been implemented and are described together with the results of machine studies aimed at improving the collider efficiency and testing new operating conditions.
Date: September 1, 2006
Creator: Gallo, A.; Alesini, D.; Biagini, M.E.; Biscari, C.; Boni, R.; Boscolo, M. et al.
System: The UNT Digital Library
Design and Preliminary Monte Carlo Calculations of an Active Compton Suppressed LaBr3(Ce) Detector System for TRU Assay in Remote-Handled Wastes (open access)

Design and Preliminary Monte Carlo Calculations of an Active Compton Suppressed LaBr3(Ce) Detector System for TRU Assay in Remote-Handled Wastes

Recent studies indicate LaBr3(Ce) scintillation detectors have desirable attributes, such as room temperature operability, which may make them viable alternatives as primary detectors (PD) in a Compton suppression spectrometer (CSS) used for remote-handled transuranic (RH-TRU) waste assay. A CSS with a LaBr3(Ce) PD has been designed and its expected performance evaluated using Monte Carlo analysis. The unique design of this unit minimizes the amount of "dead" material between the PD and the secondary guard detector. The analysis results indicate that this detector will have a relatively high Compton-suppression capability, with greater suppression ability for large angle-scattered photons in the PD. J. K. Hartwell1, M. E. McIlwain1, R. P. Gardner2, J. Kulisek3 1) Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415-2114 USA 2) North Carolina State University, Dept of Nuclear Eng., PO Box 7909, Raleigh, NC 27695 USA 3) Ohio State University, Columbus, Ohio 43210 The US Department of Energy’s transuranic (TRU) waste inventory includes about 4,500 m3 of remote-handled TRU (RH-TRU) wastes. The RH-TRU waste stream is composed of a variety of containerized waste forms having a contact surface dose rate that exceeds 2 mSv/hr (200 mrem/hr) containing waste materials with a total TRU concentration greater than 3700 …
Date: September 1, 2006
Creator: Kulisek, J.; Hartwell, J. K.; McIlwain, M. E. & Gardner, R. P.
System: The UNT Digital Library
Design of a Thermal Imaging Diagnostic Using 90-Degree, Off-Axis, Parabolic Mirrors (open access)

Design of a Thermal Imaging Diagnostic Using 90-Degree, Off-Axis, Parabolic Mirrors

Thermal imaging is an important, though challenging, diagnostic for shockwave experiments. Shock-compressed materials undergo transient temperature changes that cannot be recorded with standard (greater than ms response time) infrared detectors. A further complication arises when optical elements near the experiment are destroyed. We have designed a thermal-imaging system for studying shock temperatures produced inside a gas gun at Sandia National Laboratories. Inexpensive, diamond-turned, parabolic mirrors relay an image of the shocked target to the exterior of the gas gun chamber through a sapphire vacuum port. The 3000–5000-nm portion of this image is directed to an infrared camera which acquires a snapshot of the target with a minimum exposure time of 150 ns. A special mask is inserted at the last intermediate image plane, to provide dynamic thermal background recording during the event. Other wavelength bands of this image are split into high-speed detectors operating at 900–1700 nm, and at 1700–3000 nm for timeresolved pyrometry measurements. This system incorporates 90-degree, off-axis parabolic mirrors, which can collect low f/# light over a broad spectral range, for high-speed imaging. Matched mirror pairs must be used so that aberrations cancel. To eliminate image plane tilt, proper tip-to-tip orientation of the parabolic mirrors is required. …
Date: September 1, 2006
Creator: Malone, Robert M.; Becker, Steven A.; Dolan, Daniel H.; Hacking, Richard G.; Hickman, Randy J.; Kaufman, Morris I. et al.
System: The UNT Digital Library
Design of an XUV FEL Driven by the Laser-Plasma Accelerator at theLBNL LOASIS Facility (open access)

Design of an XUV FEL Driven by the Laser-Plasma Accelerator at theLBNL LOASIS Facility

We present a design for a compact FEL source of ultrafast, high-peak flux, soft x-ray pulses employing a high-current, GeV-energy electron beam from the existing laser-plasma accelerator at the LBNL LOASIS laser facility. The proposed ultra-fast source would be intrinsically temporally synchronized to the drive laser pulse, enabling pump-probe studies in ultra-fast science with pulse lengths of tens of fs. Owing both to the high current ({approx} 10 kA) and reasonable charge/pulse ({approx} 0.1-0.5 nC) of the laser-plasma-accelerated electron beams, saturated output fluxes are potentially 10{sup 13}--10{sup 14} photons/pulse. We examine devices based both on SASE and high-harmonic generated input seeds to give improved coherence and reduced undulator length, presenting both analytic scalings and numerical simulation results for expected FEL performance. A successful source would result in a new class of compact laser-driven FELs in which a conventional RF accelerator is replaced by a GeV-class laser-plasma accelerator whose active acceleration region is only a few cm in length.
Date: September 1, 2006
Creator: Schroeder, Carl B.; Fawley, W. M.; Esarey, Eric & Leemans, W. P.
System: The UNT Digital Library
Detecting Distributed Scans Using High-Performance Query-DrivenVisualization (open access)

Detecting Distributed Scans Using High-Performance Query-DrivenVisualization

Modern forensic analytics applications, like network trafficanalysis, perform high-performance hypothesis testing, knowledgediscovery and data mining on very large datasets. One essential strategyto reduce the time required for these operations is to select only themost relevant data records for a given computation. In this paper, wepresent a set of parallel algorithms that demonstrate how an efficientselection mechanism -- bitmap indexing -- significantly speeds up acommon analysist ask, namely, computing conditional histogram on verylarge datasets. We present a thorough study of the performancecharacteristics of the parallel conditional histogram algorithms. Asacase study, we compute conditional histograms for detecting distributedscans hidden in a dataset consisting of approximately 2.5 billion networkconnection records. We show that these conditional histograms can becomputed on interactive timescale (i.e., in seconds). We also show how toprogressively modify the selection criteria to narrow the analysis andfind the sources of the distributed scans.
Date: September 1, 2006
Creator: Stockinger, Kurt; Bethel, E. Wes; Campbell, Scott; Dart, Eli & Wu,Kesheng
System: The UNT Digital Library
Determining neutrino mass hierarchy by precise measurements of two delta m**2 in electron-neutrino and muon-neutrino disappearance experiments (open access)

Determining neutrino mass hierarchy by precise measurements of two delta m**2 in electron-neutrino and muon-neutrino disappearance experiments

In this talk, the authors discuss the possibility of determining the neutrino mass hierarchy by comparing the two effective atmospheric neutrino mass squared differences measured, respectively, in electron, and in muon neutrino disappearance oscillation experiments. if the former, is larger (smaller) than the latter, the mass hierarchy is of normal (inverted) type. They consider two very high precision (a few per mil) measurements of such mass squared differences by the phase II of the T2K (Tokai-to-Kamioka) experiment and by the novel Moessbauer enhanced resonant {bar {nu}}{sub e} absorption technique. Under optimistic assumptions for the systematic errors of both measurements, they determine the region of sensitivities where the mass hierarchy can be distinguished. Due to the tight space limitation, they present only the general idea and show a few most important plots.
Date: September 1, 2006
Creator: Minakata, H.; U., /Tokyo Metropolitan; Nunokawa, H.; /Rio de Janeiro, Pont. U. Catol.; Parke, Stephen J.; /Fermilab et al.
System: The UNT Digital Library
Developing Multiple Diverse Potential Designs for Heat Transfer Utilizing Graph Based Evolutionary Algorithms (open access)

Developing Multiple Diverse Potential Designs for Heat Transfer Utilizing Graph Based Evolutionary Algorithms

This paper examines the use of graph based evolutionary algorithms (GBEAs) to find multiple acceptable solutions for heat transfer in engineering systems during the optimization process. GBEAs are a type of evolutionary algorithm (EA) in which a topology, or geography, is imposed on an evolving population of solutions. The rates at which solutions can spread within the population are controlled by the choice of topology. As in nature geography can be used to develop and sustain diversity within the solution population. Altering the choice of graph can create a more or less diverse population of potential solutions. The choice of graph can also affect the convergence rate for the EA and the number of mating events required for convergence. The engineering system examined in this paper is a biomass fueled cookstove used in developing nations for household cooking. In this cookstove wood is combusted in a small combustion chamber and the resulting hot gases are utilized to heat the stove’s cooking surface. The spatial temperature profile of the cooking surface is determined by a series of baffles that direct the flow of hot gases. The optimization goal is to find baffle configurations that provide an even temperature distribution on the …
Date: September 1, 2006
Creator: Jr., David J. Muth
System: The UNT Digital Library
Development and Attestation of Gamma-Ray Measurement Methodologies for use by Rostekhnadzor Inspectors in the Russian Federation (open access)

Development and Attestation of Gamma-Ray Measurement Methodologies for use by Rostekhnadzor Inspectors in the Russian Federation

Development and attestation of gamma-ray non-destructive assay measurement methodologies for use by inspectors of the Russian Federal Service for Environmental, Technological, and Nuclear Oversight (Rostekhnadzor, formerly Gosatomnadzor or GAN), as well as for use by Russian nuclear facilities, has been completed. Specifically, a methodology utilizing the gamma-ray multi group analysis (MGA) method for determining plutonium isotopic composition has been developed, while existing methodologies to determining uranium enrichment and isotopic composition have been revised to make them more appropriate to the material types and conditions present in nuclear facilities in the Russian Federation. This paper will discuss the development and revision of these methodologies, the metrological characteristics of the final methodologies, as well as the limitations and concerns specific to the utilization of these analysis methods in the Russian Federation.
Date: September 1, 2006
Creator: Sanders, Jeff
System: The UNT Digital Library
Development of 3D integrated circuits for HEP (open access)

Development of 3D integrated circuits for HEP

Three dimensional integrated circuits are well suited to improving circuit bandwidth and increasing effective circuit density. Recent advances in industry have made 3D integrated circuits an option for HEP. The 3D technology is discussed in this paper and several examples are shown. Design of a 3D demonstrator chip for the ILC is presented.
Date: September 1, 2006
Creator: Yarema, R.
System: The UNT Digital Library
Development of a Non-Magnetic Inertial Sensor for Vibration Stabilization in a Linear Collider (open access)

Development of a Non-Magnetic Inertial Sensor for Vibration Stabilization in a Linear Collider

One of the options for controlling vibration of the final focus magnets in a linear collider is to use active feedback based on accelerometers. While commercial geophysics sensors have noise performance that substantially exceeds the requirements for a linear collider, they are physically large, and cannot operate in the strong magnetic field of the detector. Conventional nonmagnetic sensors have excessive noise for this application. We report on the development of a non-magnetic inertial sensor, and on a novel commercial sensor both of which have demonstrated the required noise levels for this application.
Date: September 1, 2006
Creator: Frisch, Josef; Decker, Valentin; Doyle, Eric; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas et al.
System: The UNT Digital Library
Dynamic Alignment in Presence of Ground Motion and Technical Noise (open access)

Dynamic Alignment in Presence of Ground Motion and Technical Noise

None
Date: September 1, 2006
Creator: Ivanov, Valentin Y.
System: The UNT Digital Library
Effects of Membrane- and Catalyst-layer-thickness Nonuniformitiesin Polymer-electrolyte Fuel Cells (open access)

Effects of Membrane- and Catalyst-layer-thickness Nonuniformitiesin Polymer-electrolyte Fuel Cells

In this paper, results from mathematical, pseudo 2-D simulations are shown for four different along-the-channel thickness distributions of both the membrane and cathode catalyst layer. The results and subsequent analysis clearly demonstrate that for the membrane thickness distributions, cell performance is affected a few percent under low relative-humidity conditions and that the position along the gas channel is more important than the local thickness variations. However, for the catalyst-layer thickness distributions, global performance is not impacted, although for saturated conditions there is a large variability in the local temperature and performance depending on the thickness.
Date: September 1, 2006
Creator: Weber, Adam Z. & Newman, John
System: The UNT Digital Library
An Enhanced GINGERSimulation Code with Harmonic Emission and HDF5IO Capabilities (open access)

An Enhanced GINGERSimulation Code with Harmonic Emission and HDF5IO Capabilities

GINGER [1] is an axisymmetric, polychromatic (r-z-t) FEL simulation code originally developed in the mid-1980's to model the performance of single-pass amplifiers. Over the past 15 years GINGER's capabilities have been extended to include more complicated configurations such as undulators with drift spaces, dispersive sections, and vacuum chamber wakefield effects; multi-pass oscillators; and multi-stage harmonic cascades. Its coding base has been tuned to permit running effectively on platforms ranging from desktop PC's to massively parallel processors such as the IBM-SP. Recently, we have made significant changes to GINGER by replacing the original predictor-corrector field solver with a new direct implicit algorithm, adding harmonic emission capability, and switching to the HDF5 IO library [2] for output diagnostics. In this paper, we discuss some details regarding these changes and also present simulation results for LCLS SASE emission at {lambda} = 0.15 nm and higher harmonics.
Date: September 1, 2006
Creator: Fawley, William M.
System: The UNT Digital Library
Entropy Generation In The Viscous Layer Of A Turbulent Channel Flow (open access)

Entropy Generation In The Viscous Layer Of A Turbulent Channel Flow

The local (pointwise) entropy generation rate per unit volume S''' is a key to improving many energy processes and applications. Entropy generation due to friction occurs from viscous dissipation of mean-flow kinetic energy (called "direct dissipation") and dissipation of turbulent kinetic energy into thermal energy ("indirect" or turbulent dissipation). The objective of the present study is to compare two approaches for the prediction of S''' for the viscous layer in near asymptotic (high Reynolds number) turbulent flows. By employing available direct numerical simulations (DNS) it was found that about two-thirds of the entropy generation occurs in this layer. A popular approximate approach does not agree with the result from the more exact evaluation of S''' but its integral falls within about four per cent at the edge of the viscous layer.
Date: September 1, 2006
Creator: McEligot, D. M.; Walsh, E. J.; Laurien, E. & Wolf, James R.
System: The UNT Digital Library