A New Pad-Based Neutron Detector for Stereo Coded Aperture Thermal Neutron Imaging (open access)

A New Pad-Based Neutron Detector for Stereo Coded Aperture Thermal Neutron Imaging

N/A
Date: October 22, 2013
Creator: Dioszegi, I.; Yu, B.; Smith, G.; Schaknowski, N.; Fried, J.; Vanier, P. E. et al.
System: The UNT Digital Library
Use of Virtual Frisch-Grid CdZnTe Detectors to Attain Sub-millimeter Spatial Resolution (open access)

Use of Virtual Frisch-Grid CdZnTe Detectors to Attain Sub-millimeter Spatial Resolution

N/A
Date: October 22, 2013
Creator: Lee, K.; Bolotnikov, A. E.; Bae, S.; Roy. N. U.; Camarda, G. S.; Petric, M. et al.
System: The UNT Digital Library
Analysis and Simulation of Beam Ion Instability in ILC Damping Ring with Multi-gas Species (open access)

Analysis and Simulation of Beam Ion Instability in ILC Damping Ring with Multi-gas Species

None
Date: October 22, 2012
Creator: Wang, Lanfa & Pivi, Mauro
System: The UNT Digital Library
Lessons Re-learned: The Little Things (open access)

Lessons Re-learned: The Little Things

This slide show discusses: connector choices; polishing technique (manual vs. machine); fiber interconnect construction; and deployment of fiber in the field.
Date: October 22, 2012
Creator: Perez, C., Lewis, T.
System: The UNT Digital Library
Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel (open access)

Management Of Hanford KW Basin Knockout Pot Sludge As Spent Nuclear Fuel

CH2M HILL Plateau Remediation Company (CHPRC) and AREVA Federal Services, LLC (AFS) have been working collaboratively to develop and deploy technologies to remove, transport, and interim store remote-handled sludge from the 10S-K West Reactor Fuel Storage Basin on the U.S. Department of Energy (DOE) Hanford Site near Richland, WA, USA. Two disposal paths exist for the different types of sludge found in the K West (KW) Basin. One path is to be managed as Spent Nuclear Fuel (SNF) with eventual disposal at an SNF at a yet to be licensed repository. The second path will be disposed as remote-handled transuranic (RH-TRU) waste at the Waste Isolation Pilot Plant (WIPP) in Carlsbad, NM. This paper describes the systems developed and executed by the Knockout Pot (KOP) Disposition Subproject for processing and interim storage of the sludge managed as SNF, (i.e., KOP material).
Date: October 22, 2012
Creator: Raymond, R. E. & Evans, K. M.
System: The UNT Digital Library
Nuclear PDFs (open access)

Nuclear PDFs

N/A
Date: October 22, 2012
Creator: D., De Florian; M., Stratmann; Zurita, P. & Sassot, R.
System: The UNT Digital Library
Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes (open access)

Radioactive Demonstrations Of Fluidized Bed Steam Reforming (FBSR) With Hanford Low Activity Wastes

Several supplemental technologies for treating and immobilizing Hanford low activity waste (LAW) are being evaluated. One immobilization technology being considered is Fluidized Bed Steam Reforming (FBSR) which offers a low temperature (700-750?C) continuous method by which wastes high in organics, nitrates, sulfates/sulfides, or other aqueous components may be processed into a crystalline ceramic (mineral) waste form. The granular waste form produced by co-processing the waste with kaolin clay has been shown to be as durable as LAW glass. The FBSR granular product will be monolithed into a final waste form. The granular component is composed of insoluble sodium aluminosilicate (NAS) feldspathoid minerals such as sodalite. Production of the FBSR mineral product has been demonstrated both at the industrial, engineering, pilot, and laboratory scales on simulants. Radioactive testing at SRNL commenced in late 2010 to demonstrate the technology on radioactive LAW streams which is the focus of this study.
Date: October 22, 2012
Creator: Jantzen, Carol M.; Crawford, C. L.; Burket, P. R.; Bannochie, C. J.; Daniel, W. G.; Nash, C. A. et al.
System: The UNT Digital Library
A REALISTIC EXAMINATION OF COLD FUSION CLAIMS 24 YEARS LATER (open access)

A REALISTIC EXAMINATION OF COLD FUSION CLAIMS 24 YEARS LATER

On March 29, 1989, chemists Martin Fleischmann and Stanley Pons announced they had discovered an effect whose explanation was required to lie in the realm of nuclear reactions. Their claim, and those subsequent to it of roughly similar nature, became known as ‘cold fusion’. Research continues to this day on this effect, but what has become clear is that whatever it is, it is not a conventional fusion process. Thus the ‘cold fusion’ moniker is somewhat inappropriate and many current researchers in the field prefer the term “Low Energy Nuclear Reactions (LENR)”, although other terms have been coined for it as well. the results developed out of the LENR research do in fact show something is happening to produce signals which might be interpreted as supporting nuclear reactions (which is what encourages and sustains LENR researchers), but which can also be interpreted via a set of unique and interesting conventional processes. The focus of this document is to describe and address recent objections to such processes so that subsequent LENR research can be guided to develop information that will determine whether either set of explanations has merit. It is hoped that criteria delineated herein will aid the USDOE and other …
Date: October 22, 2012
Creator: Shanahan, K.
System: The UNT Digital Library
Tools to Implement MPDV Component Characteristics (open access)

Tools to Implement MPDV Component Characteristics

This slide show presents work on photonic Doppler velocimetry multiplexing techniques, particularly as regards measurements on components.
Date: October 22, 2012
Creator: Pena, Michael; Burke, Martin; Daykin, Edward; Emmit, Ryan; Garza, Anselmo; Gibo, Mike et al.
System: The UNT Digital Library
Enhanced Magnetism of Fe3O4 Nanoparticles with Ga Doping (open access)

Enhanced Magnetism of Fe3O4 Nanoparticles with Ga Doping

Magnetic (Ga{sub x}Fe{sub 1-x}){sub 3}O{sub 4} nanoparticles with 5%-33% gallium doping (x = 0.05-0.33) were measured using x-ray absorption spectroscopy and x-ray magnetic circular dichroism to determine that the Ga dopant is substituting for Fe{sub 3+} as Ga{sub 3+} in the tetrahedral A-site of the spinel structure, resulting in an overall increase in the total moment of the material. Frequency-dependent alternating-current magnetic susceptibility measurements showed these particles to be weakly interacting with a reduction of the cubic anisotropy energy term with Ga concentration. The element-specific dichroism spectra show that the average Fe moment is observed to increase with Ga concentration, a result consistent with the replacement of A-site Fe by Ga.
Date: October 22, 2010
Creator: Pool, V. L.; Klem, M. T.; Chorney, C. L.; Arenholz, E. & Idzerda, Y.U.
System: The UNT Digital Library
New Superheavy Element Isotopes: 242Pu(48Ca,5n)285114 (open access)

New Superheavy Element Isotopes: 242Pu(48Ca,5n)285114

The new, neutron-deficient, superheavy element isotope {sup 285}114 was produced in {sup 48}Ca irradiations of {sup 242}Pu targets at a center-of-target beam energy of 256 MeV (E* = 50 MeV). The {alpha} decay of {sup 285}114 was followed by the sequential {alpha} decay of four daughter nuclides, {sup 281}Cn, {sup 277}Ds, {sup 273}Hs, and {sup 269}Sg. {sup 265}Rf was observed to decay by spontaneous fission. The measured {alpha}-decay Q values were compared with those from a macroscopic-microscopic nuclear mass model to give insight into superheavy element shell effects. The {sup 242}Pu({sup 48}Ca,5n){sup 285}114 cross section was 0.6{sub -0.5}{sup +0.9} pb.
Date: October 22, 2010
Creator: Ellison, Paul A; Gregorich, Kenneth E.; Berryman, Jill S.; Bleuel, Darren L.; Clark, Roderick M.; Dragojevic, Irena et al.
System: The UNT Digital Library
Orbital Moment Determination in (MnxFe1-x)3O4 Nanoparticles (open access)

Orbital Moment Determination in (MnxFe1-x)3O4 Nanoparticles

Nanoparticles of (Mn{sub x}Fe{sub 1-x}){sub 3}O{sub 4} with a concentration ranging from x = 0 to 1 and a crystallite size of 14-15 nm were measured using X-ray absorption spectroscopy and X-ray magnetic circular dichroism to determine the ratio of the orbital moment to the spin moment for Mn and Fe. At low Mn concentrations, the Mn substitutes into the host Fe{sub 3}O{sub 4} spinel structure as Mn{sup 2+} in the tetrahedral A-site. The net Fe moment, as identified by the X-ray dichroism intensity, is found to increase at the lowest Mn concentrations then rapidly decrease until no dichroism is observed at 20% Mn. The average Fe orbit/spin moment ratio is determined to initially be negative and small for pure Fe{sub 3}O{sub 4} nanoparticles and quickly go to 0 by 5%-10% Mn addition. The average Mn moment is anti-aligned to the Fe moment with an orbit/spin moment ratio of 0.12 which gradually decreases with Mn concentration.
Date: October 22, 2010
Creator: Pool, V. L.; Jolley, C.; Douglas, T.; Arenholz, E. & Idzerda, Y. U.
System: The UNT Digital Library
Photodetectors for Scintillator Proportionality Measurement (open access)

Photodetectors for Scintillator Proportionality Measurement

None
Date: October 22, 2010
Creator: Moses, William W.; Choong, W. -S.; Hull, G.; Payne, S.; Cherepy, N. & Valentine, J. D.
System: The UNT Digital Library
Planning Tools for Estimating Radiation Exposure at the National Ignition Facility (open access)

Planning Tools for Estimating Radiation Exposure at the National Ignition Facility

A set of computational tools was developed to help estimate and minimize potential radiation exposure to workers from material activation in the National Ignition Facility (NIF). AAMI (Automated ALARA-MCNP Interface) provides an efficient, automated mechanism to perform the series of calculations required to create dose rate maps for the entire facility with minimal manual user input. NEET (NIF Exposure Estimation Tool) is a web application that combines the information computed by AAMI with a given shot schedule to compute and display the dose rate maps as a function of time. AAMI and NEET are currently used as work planning tools to determine stay-out times for workers following a given shot or set of shots, and to help in estimating integrated doses associated with performing various maintenance activities inside the target bay. Dose rate maps of the target bay were generated following a low-yield 10{sup 16} D-T shot and will be presented in this paper.
Date: October 22, 2010
Creator: Verbeke, J.; Young, M.; Brereton, S.; Dauffy, L.; Hall, J.; Hansen, L. et al.
System: The UNT Digital Library
Integrated process modeling for the laser inertial fusion Energy (LIFE) generation system (open access)

Integrated process modeling for the laser inertial fusion Energy (LIFE) generation system

A concept for a new fusion-fission hybrid technology is being developed at Lawrence Livermore National Laboratory. The primary application of this technology is base-load electrical power generation. However, variants of the baseline technology can be used to 'burn' spent nuclear fuel from light water reactors or to perform selective transmutation of problematic fission products. The use of a fusion driver allows very high burn-up of the fission fuel, limited only by the radiation resistance of the fuel form and system structures. As a part of this process, integrated process models have been developed to aid in concept definition. Several models have been developed. A cost scaling model allows quick assessment of design changes or technology improvements on cost of electricity. System design models are being used to better understand system interactions and to do design trade-off and optimization studies. Here we describe the different systems models and present systems analysis results. Different market entry strategies are discussed along with potential benefits to US energy security and nuclear waste disposal. Advanced technology options are evaluated and potential benefits from additional R&D targeted at the different options is quantified.
Date: October 22, 2009
Creator: Meier, W. R.; Anklam, T. M.; Erlandson, A. C.; Miles, R. R.; Simon, A. J.; Sawicki, R. et al.
System: The UNT Digital Library
RE-EVALUATION OF THE PERMEABLE MATERIAL AT THE BASE OF THE UNCONFINED AQUIFER NEAR LERF HANFORD SITE WASHINGTON (open access)

RE-EVALUATION OF THE PERMEABLE MATERIAL AT THE BASE OF THE UNCONFINED AQUIFER NEAR LERF HANFORD SITE WASHINGTON

None
Date: October 22, 2009
Creator: Smoot, J. L.
System: The UNT Digital Library
Angular Dependence of Jet Quenching Indicates Its Strong Enhancement Near the QCD Phase Transition (open access)

Angular Dependence of Jet Quenching Indicates Its Strong Enhancement Near the QCD Phase Transition

We study dependence of jet quenching on matter density, using 'tomography' of the fireball provided by RHIC data on azimuthal anisotropy v{sub 2} of high p{sub t} hadron yield at different centralities. Slicing the fireball into shells with constant (entropy) density, we derive a 'layer-wise geometrical limit' v{sub 2}{sup max} which is indeed above the data v{sub 2} < v{sub x}{sup max}. Interestingly, the limit is reached only if quenching is dominated by shells with the entropy density exactly in the near-T{sub c} region. We show two models that simultaneously describe the high p{sub t} v{sub 2} and R{sub AA} data and conclude that such a description can be achieved only if the jet quenching is few times stronger in the near-T{sub c} region relative to QGP at T > T{sub c}. One possible reason for that may be recent indications that the near-T{sub c} region is a magnetic plasma of relatively light color-magnetic monopoles.
Date: October 22, 2008
Creator: Liao, Jinfeng & Shuryak, Edward
System: The UNT Digital Library
Characterizing the nano and micro structure of concrete to improve its durability (open access)

Characterizing the nano and micro structure of concrete to improve its durability

New and advanced methodologies have been developed to characterize the nano and microstructure of cement paste and concrete exposed to aggressive environments. High resolution full-field soft X-ray imaging in the water window is providing new insight on the nano scale of the cement hydration process, which leads to a nano-optimization of cement-based systems. Hard X-ray microtomography images on ice inside cement paste and cracking caused by the alkali-silica reaction (ASR) enables three-dimensional structural identification. The potential of neutron diffraction to determine reactive aggregates by measuring their residual strains and preferred orientation is studied. Results of experiments using these tools will be shown on this paper.
Date: October 22, 2008
Creator: Monteiro, P. J. M.; Kirchheim, A. P.; Chae, S.; Fischer, P.; MacDowell, A. A.; Schaible, E. et al.
System: The UNT Digital Library
Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards (open access)

Next Generation Safeguards Initiative Workshop on Enhanced Recruiting for International Safeguards

In 2007, the National Nuclear Security Administration's Office of Nonproliferation and International Security (NA-24) completed a yearlong review of the challenges facing the international safeguards system today and over the next 25 years. The study found that without new investment in international safeguards, the U.S. safeguards technology base, and our ability to support International Atomic Energy Agency (IAEA) safeguards, will continue to erode and soon may be at risk. To reverse this trend, the then U.S. Secretary of Energy, Samuel Bodman, announced at the 2007 IAEA General Conference that the Department of Energy (DOE) would launch the Next Generation Safeguards Initiative (NGSI). He stated 'IAEA safeguards must be robust and capable of addressing proliferation threats. Full confidence in IAEA safeguards is essential for nuclear power to grow safely and securely. To this end, the U.S. Department of Energy will seek to ensure that modern technology, the best scientific expertise, and adequate resources are available to keep pace with expanding IAEA responsibilities.' To meet this goal, the NGSI objectives include the recruitment of international safeguards experts to work at the U.S. national laboratories and to serve at the IAEA's headquarters. Part of the latter effort will involve enhancing our existing efforts …
Date: October 22, 2008
Creator: Pepper, S.; Rosenthal, M.; Fishbone, L.; Occhiogrosso, D.; Carroll, C.; Dreicer, M. et al.
System: The UNT Digital Library
Potential of Photovoltaics (open access)

Potential of Photovoltaics

Presented at the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL) Fall Technical Conference 2008 and 22nd International Vacuum Web Coating Conference held October 19-22, 2008 in Myrtle Beach, South Carolina. This presentation discusses PV in the world energy portfolio, PV basics, PV technologies, and vacuum web-coating applications in PV.
Date: October 22, 2008
Creator: Nelson, B. P.
System: The UNT Digital Library
Recent Searches for Exotic Physics at the BaBar/PEP-II B-factory (open access)

Recent Searches for Exotic Physics at the BaBar/PEP-II B-factory

I present three recent results from searches for exotic physics at the BABAR/PEP-II B-factory. These results span many of the samples produced at the B-factory, including B mesons, {tau} leptons, and {Upsilon}(3S) mesons. We have searched for CPT-violation in B{sup 0} mixing and find no significant deviation from the no-violation hypothesis. We have also searched for lepton-flavor-violating decays of the {tau} using {tau}{sup -} {yields} {omega}{ell}{sup -} and {tau}{sup -} {yields} {ell}{sup -}{ell}{sup +}{ell}{sup -} and their charge conjugates. We find no evidence for these processes and set upper limits on their branching fractions. Finally, we have searched for a low-mass Higgs boson in the decay {Upsilon}(3S) {yields} {gamma}A{sup 0}, where the Higgs decays invisibly. We find no evidence for such a decay and set upper limits across a range of possible Higgs masses.
Date: October 22, 2008
Creator: Sekula, Stephen Jacob
System: The UNT Digital Library
Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water (open access)

Diffusion of a Highly-Charged Supramolecular Assembly: Direct Observation of Ion-Association in Water

Understanding the solution behavior of supramolecular assemblies is essential for a full understanding of the formation and chemistry of synthetic host-guest systems. While the interaction between host and guest molecules is generally the focus of mechanistic studies of host-guest complexes, the interaction of the host-guest complex with other species in solution remains largely unknown, although in principle accessible by diffusion studies. Several NMR techniques are available to monitor diffusion and have recently been reviewed. Pulsed gradient spin-echo (PGSE) NMR methods have attracted increasing interest, since they allow diffusion coefficients to be measured with high accuracy; they have been successfully used with observation of {sup 7}Li and {sup 31}P nuclei as well as with {sup 1}H NMR. We report here the direct measurement of diffusion coefficients to observe ion-association interactions by counter cations with a highly-charged supramolecular assembly. Raymond and coworkers have described the design and chemistry of a class of metal-ligand supramolecular assemblies over the past decade. The [Ga{sub 4}L{sub 6}]{sup 12-} (L = 1,5-bis(2,3-dihydroxybenzamido)naphthalene) (1) (Figure 1) assembly has garnered the most attention, with the exploration of the dynamics and mechanism of guest exchange as well as the ability of 1 to achieve either stoichiometric or catalytic reactions inside …
Date: October 22, 2007
Creator: University of California, Berkeley; Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Pluth, Michael D.; Tiedemann, Bryan E.F.; van Halbeek, Herman et al.
System: The UNT Digital Library
Efficient computation of Morse-Smale Complexes for three-dimensional scalar functions (open access)

Efficient computation of Morse-Smale Complexes for three-dimensional scalar functions

None
Date: October 22, 2007
Creator: Gyulassy, A; Natarajan, V; Pascucci, V & Hamann, B
System: The UNT Digital Library
Electromagnetic Models of Extragalactic Jets (open access)

Electromagnetic Models of Extragalactic Jets

Relativistic jets may be confined by large-scale, anisotropic electromagnetic stresses that balance isotropic particle pressure and disordered magnetic field. A class of axisymmetric equilibrium jet models will be described and their radiative properties outlined under simple assumptions. The partition of the jet power between electromagnetic and mechanical forms and the comoving energy density between particles and magnetic field will be discussed. Current carrying jets may be recognized by their polarization patterns. Progress and prospects for measuring this using VLBI and GLAST observations will be summarized.
Date: October 22, 2007
Creator: Lisanti, M.; Blandford, R. & /KIPAC, Menlo Park
System: The UNT Digital Library