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Performance Demonstration Program Plan for Nondestructive Assay of Drummed Wastes for the TRU Waste Characterization Program
Each testing and analytical facility performing waste characterization activities for the Waste Isolation Pilot Plant (WIPP) participates in the Performance Demonstration Program (PDP) to comply with the Transuranic Waste Acceptance Criteria for the Waste Isolation Pilot Plant (WAC) (DOE/WIPP-02-3122) and the Quality Assurance Program Document (QAPD) (CBFO-94-1012). The PDP serves as a quality control check for data generated in the characterization of waste destined for WIPP. Single blind audit samples are prepared and distributed to each of the facilities participating in the PDP. The PDP evaluates analyses of simulated headspace gases, constituents of the Resource Conservation and Recovery Act (RCRA), and transuranic (TRU) radionuclides using nondestructive assay (NDA) techniques.
Date:
April 1, 2009
Creator:
/A, N
Object Type:
Report
System:
The UNT Digital Library
Astrophysical Gyrokinetics: Kinetic and Fluid Turbulent Cascades In Magentized Weakly Collisional Plasmas
This paper presents a theoretical framework for understanding plasma turbulence in astrophysical plasmas. It is motivated by observations of electromagnetic and density fluctuations in the solar wind, interstellar medium and galaxy clusters, as well as by models of particle heating in accretion disks. All of these plasmas and many others have turbulentmotions at weakly collisional and collisionless scales. The paper focuses on turbulence in a strong mean magnetic field. The key assumptions are that the turbulent fluctuations are small compared to the mean field, spatially anisotropic with respect to it and that their frequency is low compared to the ion cyclotron frequency. The turbulence is assumed to be forced at some system-specific outer scale. The energy injected at this scale has to be dissipated into heat, which ultimately cannot be accomplished without collisions. A kinetic cascade develops that brings the energy to collisional scales both in space and velocity. The nature of the kinetic cascade in various scale ranges depends on the physics of plasma fluctuations that exist there. There are four special scales that separate physically distinct regimes: the electron and ion gyroscales, the mean free path and the electron diffusion scale. In each of the scale ranges separated …
Date:
April 23, 2009
Creator:
A.A. Schekochihin, S.C. Cowley, W. Dorland, G.W. Hammett, G.G. Howes, E. Quataert, and T. Tatsuno
Object Type:
Report
System:
The UNT Digital Library
Measurement of Particle Production and Inclusive Differential Cross Sections in p anti-p Collisions at s**(1/2) = 1.96-TeV
We report a set of measurements of particle production in inelastic p{bar p} collisions collected with a minimum-bias trigger at the Tevatron Collider with the CDF II experiment. The inclusive charged particle transverse momentum differential cross section is measured, with improved precision, over a range about ten times wider than in previous measurements. The former modeling of the spectrum appears to be incompatible with the high particle momenta observed. The dependence of the charged particle transverse momentum on the event particle multiplicity is analyzed to study the various components of hadron interactions. This is one of the observable variables most poorly reproduced by the available Monte Carlo generators. A first measurement of the event transverse energy sum differential cross section is also reported. A comparison with a PYTHIA prediction at the hadron level is performed. The inclusive charged particle differential production cross section is fairly well reproduced only in the transverse momentum range available from previous measurements. At higher momentum the agreement is poor. The transverse energy sum is poorly reproduced over the whole spectrum. The dependence of the charged particle transverse momentum on the particle multiplicity needs the introduction of more sophisticated particle production mechanisms, such as multiple parton …
Date:
April 1, 2009
Creator:
Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for CP violation in semileptonic B(s)0 decays
We have performed a search for CP violation in a sample of semileptonic B{sub s}{sup 0} decays corresponding to approximately 5 fb{sup -1} of data collected by the D0 detector in Run II at the Fermilab Tevatron Collider. A time-dependent fit to the distributions of the B{sub s}{sup 0} candidates yields the flavor-specific asymmetry a{sub fs}{sup s} = [-1.7 {+-} 9.1(stat){sub -2.3}{sup +1.2}(syst)] x 10{sup -3}. This is the most precise measurement to date of this CP violation parameter.
Date:
April 1, 2009
Creator:
Abazov, : V.
Object Type:
Article
System:
The UNT Digital Library
Oral History Interview with Marion Adams, April 10, 2009
The National Museum of the Pacific War presents an interview with Marion Adams. Adams was drafted into the Army in July of 1941. He served in the 43rd Engineer Construction Battalion, building roads, hospitals and kitchens. In 1942 he traveled to Australia, where he helped build three airstrips. They traveled to Oro Bay, Papua New Guinea, building railroads and airstrips. Adams was also trained as a medic, serving in the First Aid station. He provides details of both work experiences in engineering and building and assisting the sick and injured. He recalls helping the many wounded in Manila, as well as delivering supplies to the prison camps. He was discharged in June of 1945.
Date:
April 10, 2009
Creator:
Adams, Marion
Object Type:
Sound
System:
The Portal to Texas History
Oral History Interview with Marion Adams, April 10, 2009
The National Museum of the Pacific War presents an interview with Marion Adams. Adams was drafted into the Army in July of 1941. He served in the 43rd Engineer Construction Battalion, building roads, hospitals and kitchens. In 1942 he traveled to Australia, where he helped build three airstrips. They traveled to Oro Bay, Papua New Guinea, building railroads and airstrips. Adams was also trained as a medic, serving in the First Aid station. He provides details of both work experiences in engineering and building and assisting the sick and injured. He recalls helping the many wounded in Manila, as well as delivering supplies to the prison camps. He was discharged in June of 1945.
Date:
April 10, 2009
Creator:
Adams, Marion
Object Type:
Text
System:
The Portal to Texas History
A DATA-CENTERED COLLABORATION PORTAL TO SUPPORT GLOBAL CARBON-FLUX ANALYSIS
Carbon-climate, like other environmental sciences, has been changing. Large-scalesynthesis studies are becoming more common. These synthesis studies are often conducted by science teams that are geographically distributed and on datasets that are global in scale. A broad array of collaboration and data analytics tools are now available that could support these science teams. However, building tools that scientists actually use is hard. Also, moving scientists from an informal collaboration structure to one mediated by technology often exposes inconsistencies in the understanding of the rules of engagement between collaborators. We have developed a scientific collaboration portal, called fluxdata.org, which serves the community of scientists providing and analyzing the global FLUXNET carbon-flux synthesis dataset. Key things we learned or re-learned during our portal development include: minimize the barrier to entry, provide features on a just-in-time basis, development of requirements is an on-going process, provide incentives to change leaders and leverage the opportunity they represent, automate as much as possible, and you can only learn how to make it better if people depend on it enough to give you feedback. In addition, we also learned that splitting the portal roles between scientists and computer scientists improved user adoption and trust. The fluxdata.org portal …
Date:
April 7, 2009
Creator:
Agarwal, Deborah A.; Humphrey, Marty; Beekwilder, Norm; Jackson, Keith; Goode, Monte & van Ingen, Catharine
Object Type:
Article
System:
The UNT Digital Library
Task 1 Final Report, Theoretical/Mathematical Modeling of Ultrasonic Wave Propagation in Anisotropic Polycrystalline Stainless Steels
One of the tasks of the U.S. Nuclear Regulatory Commission-sponsored project titled "Reliability of Nondestructive Examination (NDE) for Nuclear Power Plant (NPP) Inservice Examination (ISI)" is to provide collaborative assistance to Commissariat à l’Energie Atomique (CEA) in France through theoretical predictions of ultrasonic scattering by grains of cast stainless steels (CASS) components. More specifically, a mathematical treatment of ultrasonic scattering in media having duplex micro¬structure is sought because cast stainless steel components often contains larger-scale macrograins that are composed of sub-grains/colonies. In this report, we present formal mathematical theories for ultrasonic wave propagation in polycrystalline aggregates having both simple (composed of grains only) and complex microstructures (having macrograins and sub-grains/colonies). Computations based on these theories are then carried out for ultrasonic backscatter power, attenuation due to scattering, and phase velocity dispersions. Specifically, numerical results are presented for backscatter coefficient for plane longitudinal wave propagating in duplex steel containing macrograins and colonies. Furthermore, the expected propagation characteristics (attenuation coefficient and phase velocity) are computed and described in this report for plane longitudinal waves propagating in (1) steels composed of randomly oriented grains, (2) [001] aligned grains encountered in austenitic stainless steel welds and casts, and (3) duplex steels.
Date:
April 20, 2009
Creator:
Ahmed, Salahuddin & Anderson, Michael T.
Object Type:
Report
System:
The UNT Digital Library
Portable and Transparent Message Compression in MPI Libraries to Improve the Performance and Scalability of Parallel Applications
The goal of this project has been to develop a lossless compression algorithm for message-passing libraries that can accelerate HPC systems by reducing the communication time. Because both compression and decompression have to be performed in software in real time, the algorithm has to be extremely fast while still delivering a good compression ratio. During the first half of this project, they designed a new compression algorithm called FPC for scientific double-precision data, made the source code available on the web, and published two papers describing its operation, the first in the proceedings of the Data Compression Conference and the second in the IEEE Transactions on Computers. At comparable average compression ratios, this algorithm compresses and decompresses 10 to 100 times faster than BZIP2, DFCM, FSD, GZIP, and PLMI on the three architectures tested. With prediction tables that fit into the CPU's L1 data acache, FPC delivers a guaranteed throughput of six gigabits per second on a 1.6 GHz Itanium 2 system. The C source code and documentation of FPC are posted on-line and have already been downloaded hundreds of times. To evaluate FPC, they gathered 13 real-world scientific datasets from around the globe, including satellite data, crash-simulation data, and …
Date:
April 17, 2009
Creator:
Albonesi, David & Burtscher, Martin
Object Type:
Text
System:
The UNT Digital Library
Timpson & Tenaha News (Timpson, Tex.), Vol. 27, No. 13, Ed. 1 Thursday, April 2, 2009
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
April 2, 2009
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 27, No. 14, Ed. 1 Thursday, April 9, 2009
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
April 9, 2009
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 27, No. 15, Ed. 1 Thursday, April 16, 2009
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
April 16, 2009
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 27, No. 16, Ed. 1 Thursday, April 23, 2009
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
April 23, 2009
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Timpson & Tenaha News (Timpson, Tex.), Vol. 28, No. 16, Ed. 1 Thursday, April 30, 2009
Weekly newspaper from Timpson, Texas that includes local, state, and national news along with advertising.
Date:
April 30, 2009
Creator:
Alexander, Nancy
Object Type:
Newspaper
System:
The Portal to Texas History
Time-Dependent Measure of a Nano-Scale Force-Pulse Driven by the Axonemal Dynein Motors in Individual Live Sperm Cells
Nano-scale mechanical forces generated by motor proteins are crucial to normal cellular and organismal functioning. The ability to measure and exploit such forces would be important to developing motile biomimetic nanodevices powered by biological motors for Nanomedicine. Axonemal dynein motors positioned inside the sperm flagellum drive microtubule sliding giving rise to rhythmic beating of the flagellum. This force-generating action makes it possible for the sperm cell to move through viscous media. Here we report new nano-scale information on how the propulsive force is generated by the sperm flagellum and how this force varies over time. Single cell recordings reveal discrete {approx}50 ms pulses oscillating with amplitude 9.8 {+-} 2.6 nN independent of pulse frequency (3.5-19.5 Hz). The average work carried out by each cell is 4.6 x 10{sup -16} J per pulse, equivalent to the hydrolysis of {approx}5,500 ATP molecules. The mechanochemical coupling at each active dynein head is {approx}2.2 pN/ATP, and {approx}3.9 pN per dynein arm, in agreement with previously published values obtained using different methods.
Date:
April 23, 2009
Creator:
Allen, M J; Rudd, R E; McElfresh, M W & Balhorn, R
Object Type:
Article
System:
The UNT Digital Library
The Genome Sequence of the psychrophilic archaeon, Methanococcoides burtonii: the Role of Genome Evolution in Cold-adaptation
Psychrophilic archaea are abundant and perform critical roles throughout the Earth's expansive cold biosphere. Here we report the first complete genome sequence for a psychrophilic methanogenic archaeon, Methanococcoides burtonii. The genome sequence was manually annotated including the use of a five tiered Evidence Rating system that ranked annotations from Evidence Rating (ER) 1 (gene product experimentally characterized from the parent organism) to ER5 (hypothetical gene product) to provide a rapid means of assessing the certainty of gene function predictions. The genome is characterized by a higher level of aberrant sequence composition (51%) than any other archaeon. In comparison to hyper/thermophilic archaea which are subject to selection of synonymous codon usage, M. burtonii has evolved cold adaptation through a genomic capacity to accommodate highly skewed amino acid content, while retaining codon usage in common with its mesophilic Methanosarcina cousins. Polysaccharide biosynthesis genes comprise at least 3.3% of protein coding genes in the genome, and Cell wall/membrane/envelope biogenesis COG genes are over-represented. Likewise, signal transduction (COG category T) genes are over-represented and M. burtonii has a high 'IQ' (a measure of adaptive potential) compared to many methanogens. Numerous genes in these two over-represented COG categories appear to have been acquired from {var_epsilon}- …
Date:
April 1, 2009
Creator:
Allen, Michelle A.; Lauro, Federico M.; Williams, Timothy J.; Burg, Dominic; Siddiqui, Khawar S.; De Francisci, David et al.
Object Type:
Article
System:
The UNT Digital Library
The Slow:Fast substitution ratio reveals changing patterns of natural selection in gamma-proteobacterial genomes
Different microbial species are thought to occupy distinct ecological niches, subjecting each species to unique selective constraints, which may leave a recognizable signal in their genomes. Thus, it may be possible to extract insight into the genetic basis of ecological differences among lineages by identifying unusual patterns of substitutions in orthologous gene or protein sequences. We use the ratio of substitutions in slow versus fast-evolving sites (nucleotides in DNA, or amino acids in protein sequence) to quantify deviations from the typical pattern of selective constraint observed across bacterial lineages. We propose that elevated S:F in one branch (an excess of slow-site substitutions) can indicate a functionally-relevant change, due to either positive selection or relaxed evolutionary constraint. In a genome-wide comparative study of gamma-proteobacterial proteins, we find that cell-surface proteins involved with motility and secretion functions often have high S:F ratios, while information-processing genes do not. Change in evolutionary constraints in some species is evidenced by increased S:F ratios within functionally-related sets of genes (e.g., energy production in Pseudomonas fluorescens), while other species apparently evolve mostly by drift (e.g., uniformly elevated S:F across most genes in Buchnera spp.). Overall, S:F reveals several species-specific, protein-level changes with potential functional/ecological importance. As microbial …
Date:
April 15, 2009
Creator:
Alm, Eric & Shapiro, B. Jesse
Object Type:
Article
System:
The UNT Digital Library
Ensemble: 2009-04-19 – 12th Annual African Cultural Festival
Access:
Use of this item is restricted to the UNT Community
Ensemble concert performed at the UNT College of Music Concert Hall.
Date:
April 19, 2009
Creator:
Alorwoyie, Gideon Foli
Object Type:
Sound
System:
The UNT Digital Library
Southwest Retort, Volume 61, Number 8, April 2009
This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date:
April 2009
Creator:
American Chemical Society. Dallas/Fort Worth Section.
Object Type:
Journal/Magazine/Newsletter
System:
The UNT Digital Library
Multi-Channel Auto-Dilution System for Remote Continuous Monitoring of High Soil-CO2 Fluxes
Geological sequestration has the potential capacity and longevity to significantly decrease the amount of anthropogenic CO2 introduced into the atmosphere by combustion of fossil fuels such as coal. Effective sequestration, however, requires the ability to verify the integrity of the reservoir and ensure that potential leakage rates are kept to a minimum. Moreover, understanding the pathways by which CO2 migrates to the surface is critical to assessing the risks and developing remediation approaches. Field experiments, such as those conducted at the Zero Emissions Research and Technology (ZERT) project test site in Bozeman, Montana, require a flexible CO2 monitoring system that can accurately and continuously measure soil-surface CO2 fluxes for multiple sampling points at concentrations ranging from background levels to several tens of percent. To meet this need, PNNL is developing a multi-port battery-operated system capable of both spatial and temporal monitoring of CO2 at concentrations from ambient to at least 150,000 ppmv. This report describes the system components (sampling chambers, measurement and control system, and power supply) and the results of a field test at the ZERT site during the late summer and fall of 2008. While the system performed well overall during the field test, several improvements to the …
Date:
April 23, 2009
Creator:
Amonette, James E. & Barr, Jonathan L.
Object Type:
Report
System:
The UNT Digital Library
Groundwater Availability Model for the Edwards-Trinity (Plateau) and Pecos Valley Aquifers of Texas
This report describes the study area, previous aquifer investigations, and hydrogeologic setting used to develop the Edwards Trinity and Pecos Valley aquifers conceptual models, and provides details on the study and suggestions for future model improvements.
Date:
April 2009
Creator:
Anaya, Roberto & Jones, Ian
Object Type:
Report
System:
The Portal to Texas History
High quality ZnO:Al transparent conducting oxide films synthesized by pulsed filtered cathodic arc deposition
Aluminum-doped zinc oxide, ZnO:Al or AZO, is a well-known n-type transparent conducting oxide with great potential in a number of applications currently dominated by indium tin oxide (ITO). In this study, the optical and electrical properties of AZO thin films deposited on glass and silicon by pulsed filtered cathodic arc deposition are systematically studied. In contrast to magnetron sputtering, this technique does not produce energetic negative ions, and therefore ion damage can be minimized. The quality of the AZO films strongly depends on the growth temperature while only marginal improvements are obtained with post-deposition annealing. The best films, grown at a temperature of about 200?C, have resistivities in the low to mid 10-4 Omega cm range with a transmittance better than 85percent in the visible part of the spectrum. It is remarkable that relatively good films of small thickness (60 nm) can be fabricated using this method.
Date:
April 24, 2009
Creator:
Anders, Andre; Lim, Sunnie H.N.; Yu, Kin Man; Andersson, Joakim; Rosen, Johanna; McFarland, Mike et al.
Object Type:
Article
System:
The UNT Digital Library
Using Multiple Unmanned Systems for a Site Security Task
Unmanned systems are often used to augment the ability of humans to perform challenging tasks. While the value of individual unmanned vehicles have been proven for a variety of tasks, it is less understood how multiple unmanned systems should be used together to accomplish larger missions such as site security. The purpose of this paper is to discuss efforts by researchers at the Idaho National Laboratory (INL) to explore the utility and practicality of operating multiple unmanned systems for a site security mission. This paper reviews the technology developed for a multi-agent mission and summarizes the lessons-learned from a technology demonstration.
Date:
April 1, 2009
Creator:
Anderson, Matthew O.; Nielsen, Curtis W.; McKay, Mark D.; Wadsworth, Derek C.; Hruska, Ryan C. & Koudelka, John A.
Object Type:
Article
System:
The UNT Digital Library
Exact matched-beam envelopes for undepressed transport in a quadrupole lattice with unequal drift lengths and arbitrary field strength
In 1958, Courant and Snyder analyzed the problem of alternating-gradient beam transport and treated a model without focusing gaps or space charge. Recently we revisited their work and found the exactsolution for matched-beam envelopes in a linear quadrupole lattice [O.A. Anderson and L.L. LoDestro, Phys. Rev. ST Accel. Beams, 2009]. We extend that work here to include the effect of gaps. We derive the exact envelopes and show results for various field strengths, occupancies eta,and gap-length ratios. We find the peak envelope excursion. It has a broad minimum as a function of the phase advance sigma (typically around 34o) over which it varies less than +-1percent. The phase-advance numbers also change little over the full range of gap ratios. However, the required field strengths vary appreciably. In the second stable band, the higher field strength necessitated by the lower occupancy accentuates the remarkable compression effect predicted for the FD (gapless) model.
Date:
April 29, 2009
Creator:
Anderson, O. A. & LoDestro, L. L.
Object Type:
Report
System:
The UNT Digital Library