States

Identification of Matrix Conditions that Give Rise to the Linear Coupling Resonances (open access)

Identification of Matrix Conditions that Give Rise to the Linear Coupling Resonances

N/A
Date: March 1, 2009
Creator: Gardner, C. J.
Object Type: Report
System: The UNT Digital Library
Identification of matrix conditions that give rise to the linear coupling resonances (open access)

Identification of matrix conditions that give rise to the linear coupling resonances

General definitions of horizontal and vertical amplitudes for linear coupled motion are developed from the normal form of the one-turn matrix. This leads to the identification of conditions on the matrix that give rise to the linear coupling sum and difference resonances. The correspondence with the standard hamiltonian treatment of the resonances is discussed.
Date: March 1, 2009
Creator: Gardner,C.J.
Object Type: Report
System: The UNT Digital Library
Recess Appointments Made by President George W. Bush (open access)

Recess Appointments Made by President George W. Bush

None
Date: April 15, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
SUPPORTING SAFE STORAGE OF PLUTONIUM-BEARING MATERIALS THROUGH SCIENCE, ENGINEERING AND SURVEILLANCE (open access)

SUPPORTING SAFE STORAGE OF PLUTONIUM-BEARING MATERIALS THROUGH SCIENCE, ENGINEERING AND SURVEILLANCE

Reductions in the size of the U. S. nuclear weapons arsenal resulted in the need to store large quantities of plutonium-bearing metals and oxides for prolonged periods of time. To assure that the excess plutonium from the U. S. Department of Energy (DOE) sites was stored in a safe and environmentally friendly manner the plutonium-bearing materials are stabilized and packaged according to well developed criteria published as a DOE Standard. The packaged materials are stored in secure facilities and regular surveillance activities are conducted to assure continuing package integrity. The stabilization, packaging, storage and surveillance requirements were developed through extensive science and engineering activities including those related to: plutonium-environment interactions and container pressurization, corrosion and stress corrosion cracking, plutonium-container material interactions, loss of sealing capability and changes in heat transfer characteristics. This paper summarizes some of those activities and outlines ongoing science and engineering programs that assure continued safe and secure storage of the plutonium-bearing metals and oxides.
Date: November 10, 2009
Creator: Dunn, K.; Chandler, G.; Gardner, C.; Louthan, M. & Mcclard, J.
Object Type: Article
System: The UNT Digital Library
TMTI Task 1.6 Genetic Engineering Methods and Detection (open access)

TMTI Task 1.6 Genetic Engineering Methods and Detection

A large number of GE techniques can be adapted from other microorganisms to biothreat bacteria and viruses. Detection of GE in a microorganism increases in difficulty as the size of the genetic change decreases. In addition to the size of the engineered change, the consensus genomic sequence of the microorganism can impact the difficulty of detecting an engineered change in genomes that are highly variable from strain to strain. This problem will require comprehensive databases of whole genome sequences for more genetically variable biothreat bacteria and viruses. Preliminary work with microarrays for detecting synthetic elements or virulence genes and analytic bioinformatic approaches for whole genome sequence comparison to detect genetic engineering show promise for attacking this difficult problem but a large amount of future work remains.
Date: December 4, 2009
Creator: Slezak, T.; Lenhoff, R.; Allen, J.; Borucki, M.; Vitalis, E. & Gardner, S.
Object Type: Report
System: The UNT Digital Library
Dark Matter Constraints from a Cosmic Index of Refraction (open access)

Dark Matter Constraints from a Cosmic Index of Refraction

The dark-matter candidates of particle physics invariably possess electromagnetic interactions, if only via quantum fluctuations. Taken en masse, dark matter can thus engender an index of refraction which deviates from its vacuum value. Its presence is signaled through frequency-dependent effects: the real part yields dispersive effects in propagation, and the imaginary part yields such in attenuation. We discuss theoretical constraints on the expansion of the index of refraction with frequency, the physical interpretation of the terms, and the particular observations needed to isolate its coefficients. This, with the advent of new opportunities to view gamma-ray bursts at cosmological distance scales, gives us a new probe of dark matter. As a first application we use the time delay determined from radio afterglow observations of gamma-ray bursts to limit the charge-to-mass ratio of dark matter to |{var_epsilon}|/M < 1.8 x 10{sup -5} eV{sup -1} at 95% CL.
Date: April 1, 2009
Creator: Gardner, Susan & Latimer, David C.
Object Type: Article
System: The UNT Digital Library
Distributed Wind Energy in Idaho (open access)

Distributed Wind Energy in Idaho

This project is a research and development program aimed at furthering distributed wind technology. In particular, this project addresses some of the barriers to distributed wind energy utilization in Idaho.
Date: January 31, 2009
Creator: Gardner, John; Johnson, Kathryn; Haynes, Todd & Seifert, Gary
Object Type: Report
System: The UNT Digital Library
Polarized proton performance of AGS in run 8 operation (open access)

Polarized proton performance of AGS in run 8 operation

None
Date: May 4, 2009
Creator: Huang, H.; Ahrens, L.; Bai, M.; Brown, K. A.; Gardner, C.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Compendium of Avian Occurrence Information for the Continental Shelf Waters along the Atlantic Coast of the United States: Final Report (Database Section-Seabirds) (open access)

Compendium of Avian Occurrence Information for the Continental Shelf Waters along the Atlantic Coast of the United States: Final Report (Database Section-Seabirds)

This study follows the regulatory requirements by the MMS and FWS in assessing the construction of building and wind turbines effects on marine bird populations.
Date: July 2009
Creator: O'Connell, Allan; Gardner, Beth; Gilbert, Andrew & Laurent, Kevin
Object Type: Text
System: The UNT Digital Library
A quasilinear model for solute transport under unsaturated flow (open access)

A quasilinear model for solute transport under unsaturated flow

We developed an analytical solution for solute transport under steady-state, two-dimensional, unsaturated flow and transport conditions for the investigation of high-level radioactive waste disposal. The two-dimensional, unsaturated flow problem is treated using the quasilinear flow method for a system with homogeneous material properties. Dispersion is modeled as isotropic and is proportional to the effective hydraulic conductivity. This leads to a quasilinear form for the transport problem in terms of a scalar potential that is analogous to the Kirchhoff potential for quasilinear flow. The solutions for both flow and transport scalar potentials take the form of Fourier series. The particular solution given here is for two sources of flow, with one source containing a dissolved solute. The solution method may easily be extended, however, for any combination of flow and solute sources under steady-state conditions. The analytical results for multidimensional solute transport problems, which previously could only be solved numerically, also offer an additional way to benchmark numerical solutions. An analytical solution for two-dimensional, steady-state solute transport under unsaturated flow conditions is presented. A specific case with two sources is solved but may be generalized to any combination of sources. The analytical results complement numerical solutions, which were previously required to …
Date: May 15, 2009
Creator: Houseworth, J.E. & Leem, J.
Object Type: Article
System: The UNT Digital Library
Biochemistry and genetics of autotrophy in Methanococcus (open access)

Biochemistry and genetics of autotrophy in Methanococcus

The project investigated fundamental aspects of carbon metabolism and genetics in the methane-producing archaeon Methanococcus maripaludis. The project yielded 23 peer-reviewed publications and five reviews from 1997-2007. PDFs of the peer-reviewed publications are included in the next section. Some papers of special interest are listed below. The pathway of pyruvate biosynthesis was elucidated by a combination of biochemical and physiological studies. This work characterized the very oxygen sensitive pyruvate oxidoreductase and showed that the enzyme was irreversible under physiological conditions. Evidence for the flow of electrons from the energy coupling hydrogenase b (Ehb) was presented. These results were published in the following papers. Yang, Y.L., J.N. Gluska, and W.B. Whitman (2002) Intracellular pyruvate flux in the methane-producing archaeon Methanococcus maripaludis. Arch. Microbiol. 178: 493-498. Lin, W.C., Y.L. Yang, and W.B. Whitman (2003) The anabolic pyruvate oxidoreductase from Methanococcus maripaludis. Arch. Microbiol. 179: 444-456. Lin, W., and W.B. Whitman (2004) The importance of porE and porF in the anabolic pyruvate oxidoreductase of Methanococcus maripaludis. Arch. Microbiol. 181: 68-73. Porat, I., W. Kim, E.L. Hendrickson, Q. Xia, Y. Zhang, T. Wang, F. Taub, B.C. Moore, I.J. Anderson, M. Hackett, J.A. Leigh, and W.B. Whitman (2006) Disruption of the Ehb hydrogenase operon limits …
Date: March 31, 2009
Creator: Whitman, William B.
Object Type: Report
System: The UNT Digital Library
Novel High Transverse Momentum Phenomena in Hadronic and Nuclear Collisions (open access)

Novel High Transverse Momentum Phenomena in Hadronic and Nuclear Collisions

I discuss a number of novel phenomenological features of QCD in high transverse momentum reactions. The presence of direct higher-twist processes, where a proton is produced directly in the hard subprocess, can explain the 'baryon anomaly' - the large proton-to-pion ratio seen at RHIC in high centrality heavy ion collisions. Direct hadronic processes can also account for the deviation from leading-twist PQCD scaling at fixed x{sub T} = 2 p{sub T}/{radical}s. I suggest that the 'ridge' --the same-side long-range rapidity correlation observed at RHIC in high centrality heavy ion collisions is due to the imprint of semihard DGLAP gluon radiation from initial-state partons which have transverse momenta biased toward the trigger. A model for early thermalization of the quark-gluon medium is also outlined. Rescattering interactions from gluon-exchange, normally neglected in the parton model, have a profound effect in QCD hard-scattering reactions, leading to leading-twist single-spin asymmetries, diffractive deep inelastic scattering, diffractive hard hadronic reactions, the breakdown of the Lam-Tung relation in Drell-Yan reactions, nuclear shadowing--all leading-twist dynamics not incorporated in the light-front wavefunctions of the target computed in isolation. Anti shadowing is shown to be quark flavor specific and thus different in charged and neutral deep inelastic lepton-nucleus scattering. I …
Date: April 10, 2009
Creator: Brodsky, Stanley J.
Object Type: Article
System: The UNT Digital Library
TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES (open access)

TANK 4 CHARACTERIZATION, SETTLING, AND WASHING STUDIES

A sample of PUREX sludge from Tank 4 was characterized, and subsequently combined with a Tank 51 sample (Tank 51-E1) received following Al dissolution, but prior to a supernate decant by the Tank Farm, to perform a settling and washing study to support Sludge Batch 6 preparation. The sludge source for the majority of the Tank 51-E1 sample is Tank 12 HM sludge. The Tank 51-E1 sample was decanted by SRNL prior to use in the settling and washing study. The Tank 4 sample was analyzed for chemical composition including noble metals. The characterization of the Tank 51-E1 sample, used here in combination with the Tank 4 sample, was reported previously. SRNL analyses on Tank 4 were requested by Liquid Waste Engineering (LWE) via Technical Task Request (TTR) HLE-TTR-2009-103. The sample preparation work is governed by Task Technical and Quality Assurance Plan (TTQAP), and analyses were controlled by an Analytical Study Plan and modifications received via customer communications. Additional scope included a request for a settling study of decanted Tank 51-E1 and a blend of decanted Tank 51-E1 and Tank 4, as well as a washing study to look into the fate of undissolved sulfur observed during the Tank 4 …
Date: September 29, 2009
Creator: Bannochie, C.; Pareizs, J.; Click, D. & Zamecnik, J.
Object Type: Report
System: The UNT Digital Library
Dynamic versus Static Hadronic Structure Functions (open access)

Dynamic versus Static Hadronic Structure Functions

'Static' structure functions are the probabilistic distributions computed from the square of the light-front wavefunctions of the target hadron. In contrast, the 'dynamic' structure functions measured in deep inelastic lepton-hadron scattering include the effects of rescattering associated with the Wilson line. Initial- and final-state rescattering, neglected in the parton model, can have a profound effect in QCD hard-scattering reactions, producing single-spin asymmetries, diffractive deep inelastic scattering, diffractive hard hadronic reactions, the breakdown of the Lam-Tung relation in Drell-Yan reactions, nuclear shadowing, and non-universal nuclear antishadowing|novel leading-twist physics not incorporated in the light-front wavefunctions of the target computed in isolation. I also review how 'direct' higher-twist processes--where a proton is produced in the hard subprocess itself--can explain the anomalous proton-to-pion ratio seen in high centrality heavy ion collisions.
Date: January 9, 2009
Creator: Brodsky, Stanley J.
Object Type: Article
System: The UNT Digital Library
Plastic Ablator Ignition Capsule Design for the National Ignition Facility (open access)

Plastic Ablator Ignition Capsule Design for the National Ignition Facility

The National Ignition Campaign, tasked with designing and fielding targets for fusion ignition experiments on the National Ignition Facility (NIF), has carried forward three complementary target designs for the past several years: a beryllium ablator design, a plastic ablator design, and a high-density carbon or synthetic diamond design. This paper describes current simulations and design optimization to develop the plastic ablator capsule design as a candidate for the first ignition attempt on NIF. The trade-offs in capsule scale and laser energy that must be made to achieve a comparable ignition probability to that with beryllium are emphasized. Large numbers of 1-D simulations, meant to assess the statistical behavior of the target design, as well as 2-D simulations to assess the target's susceptibility to Rayleigh-Taylor growth are presented.
Date: December 1, 2009
Creator: Clark, D. S.; Haan, S. W.; Hammel, B. A.; Salmonson, J. D.; Callahan, D. A. & Town, R. P.
Object Type: Article
System: The UNT Digital Library
Biological Air Emissions Control for an Energy Efficient Forest Products Industry of the Future (open access)

Biological Air Emissions Control for an Energy Efficient Forest Products Industry of the Future

The U.S. wood products industry is a leader in the production of innovative wood materials. New products are taking shape within a growth industry for fiberboard, plywood, particle board, and other natural material-based energy efficient building materials. However, at the same time, standards for clean air are becoming ever stricter. Emissions of volatile organic compounds (VOCs) and hazardous air pollutants (HAPs) during production of wood products (including methanol, formaldehyde, acetylaldehyde, and mercaptans) must be tightly controlled. Conventional VOC and HAP emission control techniques such as regenerative thermal oxidation (RTO) and regenerative catalytic oxidation (RCO) require significant amounts of energy and generate secondary pollutants such as nitrogen oxides and spent carbon. Biological treatment of air emissions offers a cost-effective and sustainable control technology for industrial facilities facing increasingly stringent air emission standards. A novel biological treatment system that integrates two types of biofilter systems, promises significant energy and cost savings. This novel system uses microorganisms to degrade air toxins without the use of natural gas as fuel or the creation of secondary pollutants. The replacement of conventional thermal oxidizers with biofilters will yield natural gas savings alone in the range of $82,500 to $231,000 per year per unit. Widespread use of …
Date: May 28, 2009
Creator: Jones, K. & Boswell, J.
Object Type: Report
System: The UNT Digital Library
High-Flux Stress Testing of Encapsulants for Medium-Concentration CPV Applications (open access)

High-Flux Stress Testing of Encapsulants for Medium-Concentration CPV Applications

This study involved developing methods to expose transparent encapsulant materials to high (40 to 45 UV suns) optical fluxes of UV radiation to enable rapid evaluation of materials.
Date: September 1, 2009
Creator: Kempe, M. D.; Kilkenny, M.; Moricone, T. J. & Zhang, J. Z.
Object Type: Report
System: The UNT Digital Library
THE IMPACT OF DISSOLVED SALTS ON PASTES CONTAINING FLY ASH, CEMENT AND SLAG (open access)

THE IMPACT OF DISSOLVED SALTS ON PASTES CONTAINING FLY ASH, CEMENT AND SLAG

The degree of hydration of a mixture of cementitious materials (Class F fly ash, blast furnace slag and portland cement) in highly concentrated alkaline salt solutions is enhanced by the addition of aluminate to the salt solution. This increase in the degree of hydration, as monitored with isothermal calorimetry, leads to higher values of dynamic Young's modulus and compressive strength and lower values of total porosity. This enhancement in performance properties of these cementitious waste forms by increased hydration is beneficial to the retention of the radionuclides that are also present in the salt solution. The aluminate ions in the solution act first to retard the set time of the mix but then enhance the hydration reactions following the induction period. In fact, the aluminate ions increase the degree of hydration by {approx}35% over the degree of hydration for the same mix with a lower aluminate concentration. An increase in the blast furnace slag concentration and a decrease in the water to cementitious materials ratio produced mixes with higher values of Young's modulus and lower values of total porosity. Therefore, these operational factors can be fine tuned to enhance performance properties of cementitious waste form. Empirical models for Young modulus, …
Date: September 21, 2009
Creator: Harbour, J.; Edwards, T. & Williams, V.
Object Type: Article
System: The UNT Digital Library
Texas Highways, Volume 56, Number 4, April 2009 (open access)

Texas Highways, Volume 56, Number 4, April 2009

Monthly travel magazine discussing locations and events in Texas to encourage travel within the state.
Date: April 2009
Creator: Texas. Department of Transportation.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Power Transfer Potential to the Southeast in Response to a Renewable Portfolio Standard: Interim Report 2 (open access)

Power Transfer Potential to the Southeast in Response to a Renewable Portfolio Standard: Interim Report 2

Electricity consumption in the Southeastern US, not including Florida, is approximately 24% of the total US. The availability of renewable resources for electricity production is relatively small compared to the high consumption. Therefore meeting a national renewable portfolio standard (RPS) is particularly challenging in this region. Neighboring regions, particularly to the west, have significant wind resources and given sufficient long distant transmission these resources could serve energy markets in the SE. This report looks at renewable resource supply relative to demands and the potential for power transfer into the SE. It shows that development of wind resources will depend not only on available transmission capacity but also on electricity supply and demand factors.
Date: May 1, 2009
Creator: Hadley, Stanton W; Key, Thomas S & Deb, Rajat
Object Type: Report
System: The UNT Digital Library
Feasibility of monitoring gas hydrate production with time-lapse VSP (open access)

Feasibility of monitoring gas hydrate production with time-lapse VSP

In this work we begin to examine the feasibility of using time-lapse seismic methods-specifically the vertical seismic profiling (VSP) method-for monitoring changes in hydrate accumulations that are predicted to occur during production of natural gas.
Date: November 1, 2009
Creator: Kowalsky, M.B.; Nakagawa, S. & Moridis, G.J.
Object Type: Article
System: The UNT Digital Library
Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06} (open access)

Scanning SQUID microscopy on polycrystalline SmFeAsO_{0.85} and NdFeAsO_{0.94}F_{0.06}

The order parameter of the recently-discovered ferric arsenide family of superconductors remains uncertain. Some early experiments on polycrystalline samples suggested line nodes in the order parameter, however later experiments on single crystals have strongly supported fully-gapped superconductivity. An absence of nodes does not rule out unconventional order: {pi} phase shifts between the separate Fermi sheets and time-reversal symmetry-breaking components in the order parameter remain possibilities. One test for unconventional order is scanning magnetic microscopy on well-coupled polycrystalline samples: d- or p-wave order would result in orbital frustration, leading to spontaneous currents and magnetization in the superconducting state. We have performed scanning SQUID microscopy on SmFeAsO{sub 0.85} and NdFeAsO{sub 0.94}F{sub 0.06}, and in neither material do we find spontaneous orbital currents, ruling out p- or d-wave order.
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Moler, Kathryn A.; Huber, Martin E.; Ren, Zhi-An & Zhao, Zhong-Xian
Object Type: Article
System: The UNT Digital Library
Improvement plans for the RHIC/AGS on-line model environments (open access)

Improvement plans for the RHIC/AGS on-line model environments

The on-line models for Relativistic Ion Collider (RHIC) and the RHIC pre-injectors (the AGS and the AGS Booster) can be thought of as containing our best collective knowledge of these accelerators. As we improve these on-line models we are building the framework to have a sophisticated model-based controls system. Currently the RHIC on-line model is an integral part of the controls system, providing the interface for tune control, chromaticity control, and non-linear chromaticity control. What we discuss in this paper is our vision of the future of the on-line model environment for RHIC and the RHIC preinjectors. Although these on-line models are primarily used as Courant-Snyder parameter calculators using live machine settings, we envision expanding these environments to encompass many other problem domains.
Date: August 31, 2009
Creator: Brown, K. A.; Ahrens, L.; Beebe-Wang, J.; Morris, J.; Nemesure, S.; Robert-Demolaize, G. et al.
Object Type: Article
System: The UNT Digital Library
Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy (open access)

Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and magnetization in the superconducting state. We perform scanning SQUID microscopy on a dense polycrystalline sample of NdFeAsO{sub 0.94}F{sub 0.06} with T{sub c} = 48K and find no such spontaneous currents, ruling out many of the proposed order parameters.
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
Object Type: Article
System: The UNT Digital Library