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Modeling Injection Trajectories on the Midplane of the C5 Dipole in Booster
N/A
Date:
February 1, 2005
Creator:
Gardner, C. J.
Object Type:
Report
System:
The UNT Digital Library
The J-TAC (Stephenville, Tex.), Vol. 165, No. 6, Ed. 1 Friday, February 28, 2003
Weekly student newspaper from Tarleton State University in Stephenville, Texas that includes local, state and campus news along with advertising.
Date:
February 28, 2003
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
The J-TAC (Stephenville, Tex.), Vol. 173, No. 5, Ed. 1 Thursday, February 22, 2007
Weekly student newspaper from Tarleton State University in Stephenville, Texas that includes local, state and campus news along with advertising.
Date:
February 22, 2007
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
Extinction Limits of Nonadiabatic, Catalyst-Assisted Flames in Stagnation-Point Flow
An idealized geometry corresponding to a premixed flame in stagnation-point flow is used to investigate the effects of catalysis on extending the extinction limits of on adiabatic stretched flames. Specifically, a surface catalytic reaction is assumed to occur on the stagnation plane, thereby augmenting combustion in the bulk gas with a exothermic surface reaction characterized by a reduced activation energy. Assuming the activation energies remain large, an asymptotic analysis of the resulting flame structure yields a formula for the extinction limit as a function of various parameters. In particular, it is demonstrated that the presence of a surface catalyst can extend the burning regime, thus counterbalancing the effects of heat loss and flame stretch that tend to shrink it. The analysis is relevant to small-volume combustors, where the increased surface-to-volume ratio can lead to extinction of the nonadiabatic flame in the absence of a catalyst.
Date:
February 1, 2001
Creator:
Margolis, Stephen B. & Gardner, Timothy J.
Object Type:
Report
System:
The UNT Digital Library
ACCELERATING CLOSURE AT DOE SITES WITH EM'S SCIENCE AND TECHNOLOGY PROGRAM
Technical support is important for all U.S. Department of Energy (DOE) facilities facing difficult technical issues, aggressive remediation schedules, and tight budgets. It is especially vital for closure sites, which typically are smaller and have fewer resources available to apply to remediation activities. In many cases, closure sites and other small sites no longer have staff with the expertise required to overcome technical barriers on their own. As closure deadlines approach, special technical expertise is needed to identify, evaluate, and implement new and innovative approaches that will result in significant cost and schedule improvement for the waste disposition pathway. Site ''problem holders'' must have access to world-class scientific and engineering expertise from DOE national laboratories and research facilities, private industry, and universities to address immediate critical problems. In order to have confidence in the feasibility and results of innovative approaches, site contractors need to have the benefit of the valuable experiences of technicians who have faced similar problems and found solutions. The DOE Environmental Management (EM) Science and Technology (S&T) program recognizes the need of the closure sites to solve problems aggressively and is highly responsive to this need. Technical support from the S&T program can take many forms, such …
Date:
February 27, 2003
Creator:
Walker, J. S.; Toussaint, Craig R., (info: Ph.D.) & Gardner, E. J.
Object Type:
Article
System:
The UNT Digital Library
Drift waves in stellarator geometry
Drift waves are investigated in a real three-dimensional stellarator geometry. A linear system, based on the cold ion fluid model and a ballooning mode formalism, is solved numerically in the geometry of the stellarator H1-NF. The spectra of stable and unstable modes, as well as localization, are discussed. The dependence of the spectrum of the unstable modes on the wavevector, plasma density variation, and the location in the plasma is presented.
Date:
February 7, 2000
Creator:
Persson, M.; Nadeem, M.; Lewandowski, J.L.V. & Gardner, H.J.
Object Type:
Report
System:
The UNT Digital Library
A search for W+- H ---> muon-neutrino b anti-b production at the Tevatron
All known experimental results on fundamental particles and their interactions can be described to great accuracy by a theory called the Standard Model. In the Standard Model of particle physics, the masses of particles are explained through the Higgs mechanism. The Higgs boson is the only Standard Model particle not discovered yet, and its observation or exclusion is an important test of the Standard Model. While the Standard Model predicts that a Higgs boson should exist, it does not exactly predict its mass. Direct searches have excluded a Higgs with m{sub H} < 114.4 GeV at 95% confidence level, while indirect measurements indicate that the mass should be less than 144 GeV. This analysis looks for W{sup {+-}}H {yields} {mu}{nu}{sub {mu}}b{bar b} in 1 fb{sup -1} of data collected with the D0 detector in p{bar p} collisions with {radical}s = 1.96 TeV. The analysis strategy relies on the tracking, calorimetry and muon reconstruction of the D0 experiment. The signature is a muon, missing transverse energy (E{sub T}) to account for the neutrino and two b-jets. The Higgs mass is reconstructed using the invariant mass of the two jets. Backgrounds are W{sup {+-}}b{bar b}, W{sup {+-}} c{bar c}, W{sup {+-}} + …
Date:
February 1, 2008
Creator:
Anastasoaie, Carmen Miruna & U., /Nijmegen
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Characterization of Vadose Zone Sediment: Borehole 299-W23-19 [SX -115] in the S-SX Waste Management Area.
The Tank Farm Vadose Zone Project is led by CH2M HILL Hanford Group, Inc. Their goals include defining risks from past and future single-shell tank farm activities, identifying and evaluating the efficacy of interim measures, and collecting geo-technical information and data. The purpose of these activities is to support future decisions made by the U.S. Department of Energy regarding near-term operations, future waste retrieval, and final closure activities for the single-shell tank Waste Management Areas. To help in this effort, CH2M HILL contracted with scientists at Pacific Northwest National Laboratory to analyze sediment samples collected from borehole 299-W23-19. The conclusions reached from this study support specific mechanisms influencing subsurface migration of contaminants. The mechanisms are supported by the distributions of contaminants beneath tank farms. These observations will help DOE and CH2M HILL identify and implement viable remediation and closure activities.
Date:
February 12, 2002
Creator:
Serne, R. Jeffrey; Schaef, Herbert T.; Bjornstad, Bruce N.; Lanigan, David C.; Gee, Glendon W.; Lindenmeier, Clark W. et al.
Object Type:
Report
System:
The UNT Digital Library
Summary Report of Geophysical Logging For The Seismic Boreholes Project at the Hanford Site Waste Treatment Plant.
During the period of June through October 2006, three deep boreholes and one corehole were drilled beneath the site of the Waste Treatment Plant (WTP) at the U.S. Department of Energy (DOE) Hanford Site near Richland, Washington. The boreholes were drilled to provide information on ground-motion attenuation in the basalt and interbedded sediments underlying the WTP site. This report describes the geophysical logging of the deep boreholes that was conducted in support of the Seismic Boreholes Project, defined below. The detailed drilling and geological descriptions of the boreholes and seismic data collected and analysis of that data are reported elsewhere.
Date:
February 1, 2007
Creator:
Gardner, Martin G. & Price, Randall K.
Object Type:
Report
System:
The UNT Digital Library
On Developing a Multifidelity Modeling Algorithm for System-Level Engineering Analysis
Multifidelity modeling, in which one component of a system is modeled at a significantly different level of fidelity than another, has several potential advantages. For example, a higher-fidelity component model can be evaluated in the context of a lower-fidelity full system model that provides more realistic boundary conditions and yet can be executed quickly enough for rapid design changes or design optimization. Developing such multifidelity models presents challenges in several areas, including coupling models with differing spatial dimensionalities. In this report we describe a multifidelity algorithm for thermal radiation problems in which a three-dimensional, finite-element model of a system component is embedded in a system of zero-dimensional (lumped-parameter) components. We tested the algorithm on a prototype system with three problems: heating to a constant temperature, cooling to a constant temperature, and a simulated fire environment. The prototype system consisted of an aeroshell enclosing three components, one of which was represented by a three-dimensional finite-element model. We tested two versions of the algorithm; one used the surface-average temperature of the three dimensional component to couple it to the system model, and the other used the volume-average temperature. Using the surface-average temperature provided somewhat better temperature predictions than using the volume-average temperature. …
Date:
February 1, 2003
Creator:
GARDNER,DAVID R. & HENNIGAN,GARY L.
Object Type:
Report
System:
The UNT Digital Library
Virtual PCR
The polymerase chain reaction (PCR) stands among the keystone technologies for analysis of biological sequence data. PCR is used to amplify DNA, to generate many copies from as little as a single template. This is essential, for example, in processing forensic DNA samples, pathogen detection in clinical or biothreat surveillance applications, and medical genotyping for diagnosis and treatment of disease. It is used in virtually every laboratory doing molecular, cellular, genetic, ecologic, forensic, or medical research. Despite its ubiquity, we lack the precise predictive capability that would enable detailed optimization of PCR reaction dynamics. In this LDRD, we proposed to develop Virtual PCR (VPCR) software, a computational method to model the kinetic, thermodynamic, and biological processes of PCR reactions. Given a successful completion, these tools will allow us to predict both the sequences and concentrations of all species that are amplified during PCR. The ability to answer the following questions will allow us both to optimize the PCR process and interpret the PCR results: What products are amplified when sequence mixtures are present, containing multiple, closely related targets and multiplexed primers, which may hybridize with sequence mismatches? What are the effects of time, temperature, and DNA concentrations on the concentrations …
Date:
February 23, 2006
Creator:
Gardner, S N; Clague, D S; Vandersall, J A; Hon, G & Williams, P L
Object Type:
Report
System:
The UNT Digital Library
The dynamics of diluted Ho spin ice Ho2-xYxTi2O7 studied byneutron spin echo spectroscopy
We have studied the spin relaxation in diluted spin ice Ho{sub 2-x} Y{sub x} Ti{sub 2}O{sub 7} by means of neutron spin echo spectroscopy. Remarkably, the geometrical frustration is not relieved by doping with non-magnetic Y, and the dynamics of the freezing is unaltered in the spin echo time window up to x {approx_equal} 1.6. At higher doping with non-magnetic Y (x {ge} 1.6) a new relaxation process at relatively high temperature (up to at least T {approx_equal} 55 K) appears which is more than 10 times faster than the thermally activated main relaxation process. We find evidence that over the whole range of composition all Ho spins participate in the dynamics. These results are compared to a.c. susceptibility measurements of the diluted Ho and Dy spin ice systems. X-ray absorption fine structure (EXAFS) spectra and x-ray diffraction show that the samples are structurally well ordered.
Date:
February 27, 2006
Creator:
Ehlers, G.; Gardner, J. S.; Booth, C. H.; Daniel, M.; Kam, K. C.; Cheetham, A. K. et al.
Object Type:
Article
System:
The UNT Digital Library
Metastability and Delta-Phase Retention in Plutonium Alloys Final Report of LDRD Project 01-ERD-029
The {delta} to {alpha}' phase transformation in Pu-Ga alloys is intriguing for both scientific and technological reasons. On cooling, the ductile fcc {delta}-phase transforms martensitically to the brittle monoclinic {alpha}'-phase at approximately -120 C (depending on composition). This exothermic transformation involves a 20% volume contraction and a significant increase in resistivity. The reversion of {alpha}' to {delta} involves a large temperature hysteresis beginning just above room temperature. In an attempt to better understand the underlying thermodynamics and kinetics responsible for these unusual features, we have investigated the {delta} {leftrightarrow} {alpha}' phase transformations in a Pu-0.6 wt% Ga alloy using a combination of experimental and modeling techniques.
Date:
February 11, 2004
Creator:
Wong, J; Schwartz, A J; Blobaum, K M; Krenn, C R; Wall, M A; Wolfer, W G et al.
Object Type:
Report
System:
The UNT Digital Library
A Multiplex PCR-coupled Liquid Bead Array for the Simultaneous Detection of Four Biothreat Agents
We have developed a 10-plexed PCR assay coupled to a 12-plexed liquid bead array to rapidly screen environmental samples for B. anthracis, Y. pestis, F. tularensis, and B. melitensis. Highly validated species -specific primer sets were used to simultaneously amplify multiple diagnostic regions unique to each individual pathogen. Resolution of the mix of amplified products was achieved by PCR product hybridization to corresponding probe sequences, attached to unique sets of fluorescent beads. The hybridized beads were processed through a flow cytometer, which detected presence and quantity of each PCR product. The assay was optimized to allow for maximum sensitivity in a multiplexed format. A high- throughput demonstration was performed where 384 simulated environmental samples were spiked with different amounts of B. thuringensis spores and pathogen DNA. The samples were robotically processed to extract DNA and arrayed for multiplexed PCR-liquid bead detection. The assay correctly identified the presence or absence of each pathogen and collected over 3,000 individual data points within a single 8-hour shift for approximately $1.20 per sample in a 10-plexed assay.
Date:
February 4, 2004
Creator:
Wilson, W. J.; Erler, A. M.; Nasarabadi, S. L.; Skowronski, E. W. & McCready, P. M.
Object Type:
Article
System:
The UNT Digital Library
SUPERIMPOSED MESH PLOTTING IN MCNP
The capability to plot superimposed meshes has been added to MCNP{trademark}. MCNP4C featured a superimposed mesh weight window generator which enabled users to set up geometries without having to subdivide geometric cells for variance reduction. The variance reduction was performed with weight windows on a rectangular or cylindrical mesh superimposed over the physical geometry. Experience with the new capability was favorable but also indicated that a number of enhancements would be very beneficial, particularly a means of visualizing the mesh and its values. The mathematics for plotting the mesh and its values is described here along with a description of other upgrades.
Date:
February 1, 2001
Creator:
HENDRICKS, J.
Object Type:
Article
System:
The UNT Digital Library
Quantifying the surface-subsurface biogeochemical coupling during the VERTIGO ALOHA and K2 studies
A central question addressed by the VERTIGO (VERtical Transport In the Global Ocean) study was 'What controls the efficiency of particle export between the surface and subsurface ocean'? Here, we present data from sites at ALOHA (N Central Pacific Gyre) and K2 (NW subarctic Pacific) on phytoplankton processes, and relate them via a simple planktonic foodweb model, to subsurface particle export (150-500 m). Three key factors enable quantification of the surface-subsurface coupling: a sampling design to overcome the temporal lag and spatial displacement between surface and subsurface processes; data on the size-partitioning of Net Primary Production (NPP) and subsequent transformations prior to export; estimates of the ratio of algal- to faecal-mediated vertical export flux. At ALOHA, phytoplankton were characterized by low stocks, NPP, F{sub v}/F{sub m} (N-limited), and were dominated by picoplankton. The HNLC waters at K2 were characterized by both two-fold changes in NPP and floristic shifts (high to low proportion of diatoms) between deployment 1 and 2. Prediction of export exiting the euphotic zone was based on size-partitioning of NPP, a copepod-dominated foodweb and a ratio of 0.2 (ALOHA) and 0.1 (K2) for algal:faecal particle flux. Predicted export was 20-22 mg POC m{sup -2} d{sup -1} at ALOHA …
Date:
February 25, 2008
Creator:
Boyd, P. W.; Gall, M. P.; Silver, M. W.; Bishop, J. K. B.; Coale, Susan L. & Bidigare, Robert R.
Object Type:
Article
System:
The UNT Digital Library
A high precision model of Booster Tune Control
N/A
Date:
February 1, 2002
Creator:
Brown, K.; Vanasselt, W. & Meng, W.
Object Type:
Report
System:
The UNT Digital Library
Evidence of Transformation Bursts During Thermal Cycling of a Pu-Ga Alloy
The thermodynamics and kinetics of the fcc (delta) to monoclinic (alpha-prime) phase transformation and its reversion in a plutonium-gallium alloy have been studied using differential scanning calorimetry, resistometry, and dilatometry. Under ambient conditions, the delta phase is metastable in a Pu-2.0 at% Ga alloy. Thermal cycling to below the ambient temperature results in a partial transformation to the alpha-prime phase; this transformation is composition-invariant and exhibits martensitic behavior. Because this transformation results in an unusually invariant large 25% volume contraction that cannot be fully accommodated by purely elastic adjustments, the transformation mode is expected to involve burst formation of individual alpha-prime particles. However, upon cooling, these individual bursts were not resolved by the above techniques, although signals corresponding to the overall accumulation of many alpha-prime particles were observed. On the other hand, upon heating, signals from differential scanning calorimetry, resistometry, and dilatometry showed a series of discrete changes occurring in periodic increments beginning at approximately 32 C. These features correspond to the cooperative reversion of many alpha-prime particles to the delta phase; they appear to be the result of an interplay between the autocatalytically driven reversion of a cascade of individual martensite units, and self-quenching caused by small changes of …
Date:
February 9, 2005
Creator:
Blobaum, K M; Krenn, C R; Mitchell, J N; Haslam, J J; Wall, M A; Massalski, T B et al.
Object Type:
Article
System:
The UNT Digital Library
AC Loss Measurements with a Cryocooled Sample
A new cryostat cooled by a closed-cycle Cryomech GB-37 cryocooler for superconductor measurements at temperatures down to 20 K is described. The sample is conductively coupled to the cold stage so as to minimize vibration and thermal stresses. AC losses have been measured calorimetrically in several HTSC coils that have been wound to simulate sub-scale transformer winding pairs. Stable temperatures down to 20 K were reached on these coils, allowing measurements at practical levels of ac current and I{sub c}. By using short ac current pulses, losses on individual turns could be resolved. Results are reported mainly to showcase the apparatus, measurement procedure and analytical approach.
Date:
February 15, 2001
Creator:
Schwenterly, S.W.
Object Type:
Article
System:
The UNT Digital Library
The Clifton Record (Clifton, Tex.), Vol. 110, No. 5, Ed. 1 Friday, February 4, 2005
Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
February 4, 2005
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 113, No. 8, Ed. 1 Wednesday, February 20, 2008
Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
February 20, 2008
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 110, No. 6, Ed. 1 Friday, February 11, 2005
Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
February 11, 2005
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 111, No. 7, Ed. 1 Friday, February 17, 2006
Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
February 17, 2006
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 106, No. 17, Ed. 1 Wednesday, February 28, 2001
Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date:
February 28, 2001
Creator:
Smith, W. Leon
Object Type:
Newspaper
System:
The Portal to Texas History