Report on Analyses of WAC Samples of Evaporator Overheads - 2004 (open access)

Report on Analyses of WAC Samples of Evaporator Overheads - 2004

In November and December of 2004, the Tank Farm submitted annual samples from 2F, 2H and 3H Evaporator Overhead streams for characterization to verify compliance with the new Effluent Treatment Facility (ETF) Waste Acceptance Criteria (WAC) and to look for organic species. With the exception of slightly high ammonia in the 2F evaporator overheads and high radiation control guide number for the 3H and 2F evaporator overhead samples, all the overheads samples were found to be in compliance with the Effluent Treatment Facility WAC. The ammonium concentration in the 2F-evaporator overhead, at 33 mg/L, was above the ETF waste water collection tank (WWCT) limits of 28 mg/L. The RCG Number for the 3H and 2F evaporator samples at, respectively, 1.38E-02 and 8.24E-03 were higher than the WWCT limit of 7.69E-03. The analytical detection limits for americium-241 and radium-226 in the evaporator samples were not consistently met because of low WWCT detection limits and insufficient evaporator samples.
Date: March 18, 2005
Creator: Oji, L
Object Type: Report
System: The UNT Digital Library
LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN (open access)

LX-04 VIOLENCE MEASUREMENTS- STEVEN TESTS IMPACTED BY PROJECTILES SHOT FROM A HOWITZER GUN

Characterization of the reaction violence of LX-04 explosive (85% HMX and 15% Viton A by weight) was obtained from Steven Impact Tests performed above the reaction initiation threshold. A 155 mm Howitzer propellant driven gas gun was used to accelerate the Steven Test projectiles in the range of approximately 170-300 m/s to react (ignite) the LX-04 explosive. Blast overpressure gauges, acoustic microphones, and high-speed photography characterized the level of high explosive reaction violence. A detonation in this velocity range was not observed and when comparing these results (and the Susan test results) with that of other HMX based explosives, LX-04 has a more gradual reaction violence slope as the impact velocity increases. The high binder content (15%) of the LX-04 explosive is believed to be the key factor to the lower level of violence.
Date: July 18, 2005
Creator: Chidester, S K; Vandersall, K S; Switzer, L L & Tarver, C M
Object Type: Article
System: The UNT Digital Library
On Quadratic Divergences in Supergravity, Vacuum Energy and theSupersymmetric Flavor Problem (open access)

On Quadratic Divergences in Supergravity, Vacuum Energy and theSupersymmetric Flavor Problem

We examine the phenomenological consequences ofquadratically divergent contributions to the scalar potential insupergravity effective Lagrangians. We focus specifically on the effectof these corrections on the vacuum configurationof scalar fields insoftly-broken supersymmetric theory is and the role these correctionsplay in generating non-diagonal soft scalar masses. Both effects can onlybe properly studied when the divergences are regulated in a manifestlysupersymmetric manner -- something which has ths far been neglected inpast treatments. We show how a supersymmetric regularization can impactpast conclusions about both types of phenomena and discuss what types ofhigh-energy theories are likely to be safe from unwanted flavor-changingneutral current interactions in the context of supergravity theoriesderived from heterotic string compactifications.
Date: November 18, 2005
Creator: Gaillard, Mary K. & Nelson, Brent D.
Object Type: Article
System: The UNT Digital Library
Phenomenological Theory of the Kink Instability in a Slender Plasma Column (open access)

Phenomenological Theory of the Kink Instability in a Slender Plasma Column

When one deals with a plasma column whose radius a is much smaller than its length L, one can think of it as of a thin filament whose kink instability can be adequately described simply by a 2D displacement vector, {xi}{sub x} = {xi}{sub s}(z,t); {xi}{sub y} = {xi}{sub y}(z,t). Details of the internal structure of the column such as the current, density, and axial flow velocity distribution would be lumped into some phenomenological parameters. This approach is particularly efficient in the problems with non-ideal (sheath) boundary conditions (BC) at the end electrodes, with the finite plasma resistivity, and with a substantial axial flow. With the sheath BC imposed at one of the end-plates, we find instability in the domain well below the classical Kruskal-Shafranov limit. The presence of an axial flow causes the onset of rotation of the kink and strong axial ''skewness'' of the eigenfunction, with the perturbation amplitude increasing in the flow direction. We consider the limitations of the phenomenological approach and find that they are related to the steepness with which the plasma resistivity increases at the plasma boundary with vacuum.
Date: November 18, 2005
Creator: Ryutov, D. D.; Furno, I.; Intrator, T. P.; Abbate, S. & Madziwa-Nussinov, T.
Object Type: Article
System: The UNT Digital Library
Risk Analysis for Environmental Health Triage (open access)

Risk Analysis for Environmental Health Triage

The Homeland Security Act mandates development of a national, risk-based system to support planning for, response to and recovery from emergency situations involving large-scale toxic exposures. To prepare for and manage consequences effectively, planners and responders need not only to identify zones of potentially elevated individual risk, but also to predict expected casualties. Emergency response support systems now define ''consequences'' by mapping areas in which toxic chemical concentrations do or may exceed Acute Exposure Guideline Levels (AEGLs) or similar guidelines. However, because AEGLs do not estimate expected risks, current unqualified claims that such maps support consequence management are misleading. Intentionally protective, AEGLs incorporate various safety/uncertainty factors depending on scope and quality of chemical-specific toxicity data. Some of these factors are irrelevant, and others need to be modified, whenever resource constraints or exposure-scenario complexities require responders to make critical trade-off (triage) decisions in order to minimize expected casualties. AEGL-exceedance zones cannot consistently be aggregated, compared, or used to calculate expected casualties, and so may seriously misguide emergency response triage decisions. Methods and tools well established and readily available to support environmental health protection are not yet developed for chemically related environmental health triage. Effective triage decisions involving chemical risks require a …
Date: November 18, 2005
Creator: Bogen, K T
Object Type: Article
System: The UNT Digital Library
Using E-beam Mapping to Detect Coil Misalignment in NCSX (open access)

Using E-beam Mapping to Detect Coil Misalignment in NCSX

Following assembly of the NCSX device, a program of e-beam mapping experiments is planned to validate the accuracy of the construction and assembly of the NCSX coil systems. To aid in the development of requirements for the e-beam mapping hardware and machine requirements, simulations of the e-beam mapping experiments, including various coil misalignments, have been done. The magnetic flux surface configuration was constructed using a numerical code, based on the Biot-Savart law, to calculate the magnetic field components and trace the field line trajectory many times around the torus. Magnetic surfaces are then mapped by recording the field line intersections with toroidal cross-sections of the magnetic system, much as in an actual e-beam mapping experiment.
Date: October 18, 2005
Creator: Fredrickson E, Georgiyevskiy A, Rudakov V, Zarnstorff MC
Object Type: Report
System: The UNT Digital Library
Using Decision Trees for Comparing Pattern Recognition Feature Sets (open access)

Using Decision Trees for Comparing Pattern Recognition Feature Sets

Determination of the best set of features has been acknowledged as one of the most difficult tasks in the pattern recognition process. In this report significance tests on the sort-ordered, sample-size normalized vote distribution of an ensemble of decision trees is introduced as a method of evaluating relative quality of feature sets. Alternative functional forms for feature sets are also examined. Associated standard deviations provide the means to evaluate the effect of the number of folds, the number of classifiers per fold, and the sample size on the resulting classifications. The method is applied to a problem for which a significant portion of the training set cannot be classified unambiguously.
Date: August 18, 2005
Creator: Proctor, D D
Object Type: Article
System: The UNT Digital Library
Spectroscopy of Argon Excited in an Electron Beam Ion Trap (open access)

Spectroscopy of Argon Excited in an Electron Beam Ion Trap

Argon is one of the gases best investigated and most widely used in plasma discharge devices for a multitude of applications that range from wavelength reference standards to controlled fusion experiments. Reviewing atomic physics and spectroscopic problems in various ionization stages of Ar, the past use and future options of employing an electron beam ion trap (EBIT) for better and more complete Ar data in the x-ray, EUV and visible spectral ranges are discussed.
Date: April 18, 2005
Creator: Trabert, E
Object Type: Article
System: The UNT Digital Library
Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects (open access)

Active Cathodes for Super-High Power Density Solid Oxide Fuel Cells Through Space Charge Effects

This report summarizes the work done during the eighth quarter of the project.
Date: January 18, 2005
Creator: Virkar, Anil V.
Object Type: Report
System: The UNT Digital Library

Yucca Mountain Project - Lessons Learned/Generic Implications

None
Date: October 18, 2005
Creator: McLaughlin, J.
Object Type: Presentation
System: The UNT Digital Library
Hydrogen Permeability of Mulitphase V-Ti-Ni Metallic Membranes (open access)

Hydrogen Permeability of Mulitphase V-Ti-Ni Metallic Membranes

None
Date: October 18, 2005
Creator: Adams, Thad
Object Type: Article
System: The UNT Digital Library
Laboratory astrophysics and atomic physics using the NASA/GSFC microcalorimeter spectrometers at the LLNL Electron Beam Ion Trap and Radiation Properties Facility (open access)

Laboratory astrophysics and atomic physics using the NASA/GSFC microcalorimeter spectrometers at the LLNL Electron Beam Ion Trap and Radiation Properties Facility

The 32 pixel laboratory microcalorimeter spectrometer built by the NASA/Goddard Space Flight Center is now an integral part of the spectroscopy suite used routinely by the electron beam ion trap and radiative properties group at the Lawrence Livermore National Laboratory. The second generation laboratory instrument, dubbed the XRS/EBIT, is nearly identical to the XRS instrument on the Suzaku X-ray Observatory, formerly Astro-E2. The detector array is from the same processed wafer and uses the same HgTe absorbers. it is being used to measure the photon emission from a variety of radiation sources. These include x-ray emission from laboratory simulated celestial sources, x-ray emission from highly charged ions of Au, and x-ray emission following charge exchange and radiative electron capture. The wide range of applications demonstrates the versatility of a high-resolution, high-efficiency low temperature detector that is able to collect data continually with minimal operator servicing.
Date: August 18, 2005
Creator: Brown, G.; Beiersdorfer, P.; Boyce, K.; Chen, H.; Gu, M. F.; Kahn, S. et al.
Object Type: Article
System: The UNT Digital Library
High repetition rate collisional soft x-ray lasers based on grazing incidence pumping (open access)

High repetition rate collisional soft x-ray lasers based on grazing incidence pumping

We discuss the demonstration of gain-saturated high repetition rate table-top soft x-ray lasers producing microwatt average powers at wavelengths ranging from 13.9 to 33 nm. The results were obtained heating a pre-created plasma with a picosecond optical laser pulse impinging at grazing incidence onto a pre-created plasma. This pumping geometry increases the energy deposition efficiency of the pump beam into the gain region, making it possible to saturate soft x-ray lasers in this wavelength range with a short pulse pump energy of only 1 J at 800 nm wavelength. Results corresponding to 5 Hz repetition rate operation of gain-saturated 14.7 nm Ni-like Pd and 32.6 nm line Ne-like Ti lasers pumped by a table-top Ti:sapphire laser are reported. We also discuss results obtained using a 1 {omega} 1054 nm pre-pulse and 2{omega} 527 nm short pulse from a Nd:glass pump laser. This work demonstrates the feasibility of producing compact high average power soft x-ray lasers for applications.
Date: November 18, 2005
Creator: Luther, B. M.; Wang, Y.; Larotonda, M. A.; Alessi, D.; Berrill, M.; Rocca, J. J. et al.
Object Type: Article
System: The UNT Digital Library
Combinatorial Algorithms for Computing Column Space Bases ThatHave Sparse Inverses (open access)

Combinatorial Algorithms for Computing Column Space Bases ThatHave Sparse Inverses

This paper presents a combinatorial study on the problem ofconstructing a sparse basis forthe null-space of a sparse, underdetermined, full rank matrix, A. Such a null-space is suitable forsolving solving many saddle point problems. Our approach is to form acolumn space basis of A that has a sparse inverse, by selecting suitablecolumns of A. This basis is then used to form a sparse null-space basisin fundamental form. We investigate three different algorithms forcomputing the column space basis: Two greedy approaches that rely onmatching, and a third employing a divide and conquer strategy implementedwith hypergraph partitioning followed by the greedy approach. We alsodiscuss the complexity of selecting a column basis when it is known thata block diagonal basis exists with a small given block size.
Date: March 18, 2005
Creator: Pinar, Ali; Chow, Edmond & Pothen, Alex
Object Type: Article
System: The UNT Digital Library
Iterative Schemes for Time Parallelization with Application to Reservoir Simulation (open access)

Iterative Schemes for Time Parallelization with Application to Reservoir Simulation

Parallel methods are usually not applied to the time domain because of the inherit sequentialness of time evolution. But for many evolutionary problems, computer simulation can benefit substantially from time parallelization methods. In this paper, they present several such algorithms that actually exploit the sequential nature of time evolution through a predictor-corrector procedure. This sequentialness ensures convergence of a parallel predictor-corrector scheme within a fixed number of iterations. The performance of these novel algorithms, which are derived from the classical alternating Schwarz method, are illustrated through several numerical examples using the reservoir simulator Athena.
Date: April 18, 2005
Creator: Garrido, I; Fladmark, G E; Espedal, M S & Lee, B
Object Type: Article
System: The UNT Digital Library
REFINERY INTEGRATION OF BY-PRODUCTS FROM COAL-DERIVED JET FUELS (open access)

REFINERY INTEGRATION OF BY-PRODUCTS FROM COAL-DERIVED JET FUELS

This report summarizes the accomplishments toward project goals during the first six months of the second year of the project to assess the properties and performance of coal based products. These products are in the gasoline, diesel and fuel oil range and result from coal based jet fuel production from an Air Force funded program. Specific areas of progress include generation of coal based material that has been fractionated into the desired refinery cuts, acquisition and installation of a research gasoline engine, and modification of diesel engines for use in evaluating diesel produced in the project. The desulfurization of sulfur containing components of coal and petroleum is being studied so that effective conversion of blended coal and petroleum streams can be efficiently converted to useful refinery products. Equipment is now in place to begin fuel oil evaluations to assess the quality of coal based fuel oil. Coal samples have procured and are being assessed for cleaning prior to use in coking studies.
Date: May 18, 2005
Creator: Rudnick, Leslie R.; Boehman, Andre; Song, Chunshan; Miller, Bruce & Mitchell, Gareth
Object Type: Report
System: The UNT Digital Library
Energy Loss, Range, and Electron Yield Comparisons of the CRANGEIon-Material Interaction code (open access)

Energy Loss, Range, and Electron Yield Comparisons of the CRANGEIon-Material Interaction code

We present comparisons of the CRANGE code to other well-known codes, SRIM and ASTAR, and to experimental results for ion-material interactions such as energy loss per unit length, ion range, and ion induced electron yield. These ion-material interaction simulations are relevant to the electron cloud effect in heavy ions accelerators for fusion energy and high energy density physics. Presently, the CRANGE algorithms are most accurate at energies above 1.0 MeV/amu. For calculations of energy loss per unit length of a potassium ion in stainless steel, results of CRANGE and SRIM agree to within ten percent above 1.0 MeV/amu. For calculations of the range of a helium ion in aluminum, results of CRANGE and ASTAR agree to within two percent above 1.0 MeV/amu. Finally, for calculations of ion induced electron yield for hydrogen ions striking gold, results of CRANGE agree to within ten percent with measured electron yields above 1.0 MeV/amu.
Date: January 18, 2005
Creator: Stoltz, P. H.; Veitzer, S. A.; Cohen, R. H.; Molvik, A. W. & J.-L., Vay
Object Type: Article
System: The UNT Digital Library
Short-term Variability of Extinction by Broadband Stellar Photometry (open access)

Short-term Variability of Extinction by Broadband Stellar Photometry

Aerosol optical depth variation over short-term time intervals is determined from broadband observations of stars with a whole sky imager. The main difficulty in such measurements consists of accurately separating the star flux value from the non-stellar diffuse skylight. Using correction method to overcome this difficulty, the monochromatic extinction at the ground due to aerosols is extracted from heterochromatic measurements. A form of closure is achieved by comparison with simultaneous or temporally close measurements with other instruments, and the total error of the method, as a combination of random error of measurements and systematic error of calibration and model, is assessed as being between 2.6 and 3% rms.
Date: March 18, 2005
Creator: Musat, I.C. & Ellingson, R.G.
Object Type: Article
System: The UNT Digital Library
Magnetohydrodynamic Turbulence Simulations on the Earth SimulatorUsing the Lattice Boltzmann Method (open access)

Magnetohydrodynamic Turbulence Simulations on the Earth SimulatorUsing the Lattice Boltzmann Method

None
Date: August 18, 2005
Creator: Carter, Jonathan; Soe, Min; Oliker, Leonid; Tsuda, Yoshinori; Vahala, George; Vahala, Linda et al.
Object Type: Article
System: The UNT Digital Library
Investigation of the Impact of Aerosols on Clouds During May 2003 Intensive Operational Period at the Southern Great Plains (open access)

Investigation of the Impact of Aerosols on Clouds During May 2003 Intensive Operational Period at the Southern Great Plains

The effect of aerosols on the clouds, or the so-called aerosol indirect effect (AIE), is highly uncertain (Penner et al. 2001). The estimation of the AIE can vary from 0.0 to -4.8 W/m2 in Global Climate Models (GCM). Therefore, it is very important to investigate these interactions and cloud-related physical processes further. The Aerosol Intensive Operation Period (AIOP) at the Southern Great Plains (SGP) site in May 2003 dedicated some effort towards the measurement of the Cloud Condensation Nucleus concentration (CCN) as a function of super-saturation and in relating CCN concentration to aerosol composition and size distribution. Furthermore, airborn measurement for the cloud droplet concentration was also available. Therefore this AIOP provides a good opportunity to examine the AIE. In this study, we use a Cloud Resolving Model (CRM), i.e., Active Tracer High-resolution Atmospheric Model (ATHAM), to discuss the effect of aerosol loadings on cloud droplet effective radius (Re) and concentration. The case we examine is a stratiform cloud that occurred on May 17, 2003.
Date: March 18, 2005
Creator: Guo, H.; Penner, J.E. & Herzog, M.
Object Type: Article
System: The UNT Digital Library
Statistical Estimation of the Atmospheric Aerosol Absorption Coefficient Based on the Data of Optical Measurements (open access)

Statistical Estimation of the Atmospheric Aerosol Absorption Coefficient Based on the Data of Optical Measurements

The problem of the choice of the aerosol optical constants and, in particular, imaginary part of the refractive index of particles in visible and infrared (IR) wavelength ranges is very important for calculation of the global albedo of the atmosphere in climatic models. The available models of the aerosol optical constants obtained for the prescribed chemical composition of particles (see, for example, Ivlev et al. 1973; Ivlev 1982; Volz 1972), often are far from real aerosol. It is shown in (Krekov et al. 1982) that model estimates of the optical characteristics of the atmosphere depending on the correctness of real and imaginary parts of the aerosol complex refractive index can differ by some hundreds percent. It is known that the aerosol extinction coefficient {alpha}({lambda}) obtained from measurements on a long horizontal path can be represented as {alpha}({lambda})={sigma}({lambda})+{beta}({lambda}), where {sigma} is the directed light scattering coefficient, and {beta} is the aerosol absorption coefficient. The coefficient {sigma}({lambda}) is measured by means of a nephelometer. Seemingly, if measure the values {alpha}({lambda}) and {sigma}({lambda}), it is easy to determine the value {beta}({lambda}). However, in practice it is almost impossible for a number of reasons. Firstly, the real values {alpha}({lambda}) and {sigma}({lambda}) are very close …
Date: March 18, 2005
Creator: Uzhegov, V. N.; Kozlov, V. S.; Panchenko, M. V.; Pkhalagov, Yu. A.; Pol'kin, V. V.; Terpugova, S. A. et al.
Object Type: Article
System: The UNT Digital Library
Scoria Cone Construction Mechanism, Lathrop Wells Volcano, Southern Nevada (open access)

Scoria Cone Construction Mechanism, Lathrop Wells Volcano, Southern Nevada

Scoria cones are commonly assumed to have been constructed by the accumulation of ballistically-ejected clasts from discrete and relatively coarse-grained Strombolian bursts and subsequent avalanching such that the cone slopes are at or near the angle of repose for loose scoria. The cone at the hawaiitic Lathrop Wells volcano, southern Nevada, contains deposits that are consistent with the above processes during early cone-building phases; these early deposits are composed mainly of coarse lapilli and fluidal bombs and are partially welded, indicating relatively little cooling during flight. However, the bulk of the cone is comprised of relatively fine-grained (ash and lapilli), planar beds with no welding, even within a few tens of meters of the vent. This facies is consistent with deposition by direct fallout from sustained eruption columns of relatively well-fragmented material, primarily mantling cone slopes and with a lesser degree of avalanching than is commonly assumed. A laterally extensive fallout deposit (up to 20 km from the vent) is inferred to have formed contemporaneously with these later cone deposits. This additional mechanism for construction of scoria cones may also be important at other locations, particularly where the magmas are relatively high in volatile content and where conditions promote the …
Date: January 18, 2005
Creator: Valentine, G.; Krier, D.; Perry, F. & Heiken, G.
Object Type: Report
System: The UNT Digital Library
On Sensitivity of Spectral Radiative Fluxes to Atmospheric Water Vapor in the 940 nm Region (Numerical Simulation) (open access)

On Sensitivity of Spectral Radiative Fluxes to Atmospheric Water Vapor in the 940 nm Region (Numerical Simulation)

Water vapor is well known to be a critical component in many aspects of atmospheric research, such as radiative transfer and cloud and aerosol processes. This requires both improved measurements of the columnar water vapor and its profiles in the atmosphere in a wide range of conditions, and adjustment of water vapor parameterizations in radiation codes including the perfection of spectroscopic parameters. In this paper we will present the results of comparison of our calculations and downward solar fluxes measured with Rotating Shadowband Spectroradiometer under conditions of horizontally homogeneous clouds. We also will discuss the sensitivity of atmospheric radiation characteristics to variations of water vapor in the band 940 nm: these results may be useful for development of new methods of retrieval of the total column water vapor content (WVC) in the atmosphere from data of radiation observations.
Date: March 18, 2005
Creator: Zhuravleva, T.B. & Firsov, K.M.
Object Type: Article
System: The UNT Digital Library
Multi-Filter Rotating Shadowband Radiometers Mentor Report and Baseline Surface Radiation Network Submission Status (open access)

Multi-Filter Rotating Shadowband Radiometers Mentor Report and Baseline Surface Radiation Network Submission Status

There are currently twenty-four Multi-Filter Rotating Shadowband Radiometers (MFRSR) operating within Atmospheric Radiation Measurement (ARM). Eighteen are located within the Southern Great Plains (SGP) region, there is one at each of the North Slope of Alaska (NSA) and Tropical Western Pacific (TWP) sites, and one is part of the instrumentation of the ARM Mobile Facility. At this time there are four sites, all extended facilities within the SGP, that are equipped for a MFRSR but do not have one due to instrument failure and a lack of spare instruments. In addition to the MFRSRs, there are three other MFRSR derived instruments that ARM operates. They are the Multi-Filter Radiometer (MFR), the Normal Incidence Multi-Filter Radiometer (NIMFR) and the Narrow Field of View (NFOV) radiometer. All are essentially just the head of a MFRSR used in innovative ways. The MFR is mounted on a tower and pointed at the surface. At the SGP Central Facility there is one at ten meters and one at twenty-five meters. The NSA has a MFR at each station, both at the ten meter level. ARM operates three NIMFRs; one is at the SGP Central Facility and one at each of the NSA stations. There are …
Date: March 18, 2005
Creator: Hodges, G.
Object Type: Article
System: The UNT Digital Library