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Risk assessment and radioactive waste management (open access)

Risk assessment and radioactive waste management

Problems associated with radioactive waste management, both technological and administrative, have become a serious constraint in the development of nuclear power. An approach toward understanding these problems consists of placing them in a perspective where the risks of radioactive waste management might be evaluated in relation to similar problems facing society so that consistent judgments can be made.
Date: August 16, 1977
Creator: Cohen, J.J.
System: The UNT Digital Library
Pictorial characterization of worldwide electric and hybrid vehicles (open access)

Pictorial characterization of worldwide electric and hybrid vehicles

The presentation given is intended to fulfill the several objectives of (1) documenting the pictorial review presented during ERDA's March 1, 1977, Conference on the Electric and Hybrid Vehicle Demonstration Project; (2) pictorially characterizing the present state of the electric and hybrid vehicle (EHV) art on an international scale; and (3) providing examples of the class of products expected to be available for the implementation of the early phases of Public Law 94-413. It is organized along national lines, with separate chapters for electric and hybrid vehicle programs in each of nine countries: Federal Republic of Germany, Israel, Netherlands, Sweden, the United Kingdom, France, Italy, Japan and the United States. Each chapter (except for Chapter 3) is preceded by descriptive material on the program objectives, participants and/or milestones.
Date: August 16, 1977
Creator: Kirk, R S & Barber, K F
System: The UNT Digital Library
ELECTROCHEMICAL STUDIES OF HANFORD DOUBLE SHELL TANK (DST) WASTE (open access)

ELECTROCHEMICAL STUDIES OF HANFORD DOUBLE SHELL TANK (DST) WASTE

None
Date: August 16, 2007
Creator: GA, COOKE & JB, DUNCAN
System: The UNT Digital Library
Initiation of Heated PBX-9501 Explosive When Exposed to Dynamic Loading (open access)

Initiation of Heated PBX-9501 Explosive When Exposed to Dynamic Loading

Shock initiation experiments on the heated PBX9501 explosive (95% HMX, 2.5% estane, and 2.5% nitro-plasticizer by weight) were performed at temperatures 150 C and 180 C to obtain in-situ pressure gauge data. A 101 mm diameter propellant driven gas gun was utilized to initiate the PBX9501 explosive and manganin piezo-resistive pressure gauge packages were placed between sample slices to measure time resolved local pressure histories. The run-distance-to-detonation points on the Pop-plot for these experiments showed the sensitivity of the heated material to shock loading. This work shows that heated PBX-9501 is more shock sensitive than it is at ambient conditions. Proper Ignition and Growth modeling parameters were obtained to fit the experimental data. This parameter set will allow accurate code predictions to be calculated for safety scenarios involving PBX9501 explosives at temperatures close to those at which experiments were performed.
Date: August 16, 2005
Creator: Urtiew, P A; Vandersall, K S; Tarver, C M & Garcia, F
System: The UNT Digital Library
A Shape Memory Polymer Dialysis Needle Adapter for the Reduction of Hemodynamic Stress within Arteriovenous Grafts (open access)

A Shape Memory Polymer Dialysis Needle Adapter for the Reduction of Hemodynamic Stress within Arteriovenous Grafts

A deployable, shape memory polymer adapter is investigated for reducing the hemodynamic stress caused by a dialysis needle flow within an arteriovenous graft. Computational fluid dynamics simulations of dialysis sessions with and without the adapter demonstrate that the adapter provides a significant decrease in the wall shear stress. In vitro flow visualization measurements are made within a graft model following delivery and actuation of a prototype shape memory polymer adapter. Vascular access complications resulting from arteriovenous (AV) graft failures account for over $1 billion per year in the health care costs of dialysis patients in the U.S.[1] The primary mode of failure of arteriovenous fistulas (AVF's) and polytetrafluoroethylene (PTFE) grafts is the development of intimal hyperplasia (IH) and the subsequent formation of stenotic lesions, resulting in a graft flow decline. The hemodynamic stresses arising within AVF's and PTFE grafts play an important role in the pathogenesis of IH. Studies have shown that vascular damage can occur in regions where there is flow separation, oscillation, or extreme values of wall shear stress (WSS).[2] Nevaril et al.[3] show that exposure of red blood cells to WSS's on the order of 1500 dynes/cm2 can result in hemolysis. Hemodynamic stress from dialysis needle flow …
Date: August 16, 2006
Creator: Ortega, J M; Small, W; Wilson, T S; Benett, W; Loge, J & Maitland, D J
System: The UNT Digital Library
Unraveling the Fanconi anaemia-DNA repair connection through DNA helicase and translocase activities (open access)

Unraveling the Fanconi anaemia-DNA repair connection through DNA helicase and translocase activities

How the Fanconi anaemia (FA) chromosome stability pathway functions to cope with interstrand crosslinks and other DNA lesions has been elusive, even after FANCD1 proved to be BRCA2, a partner of Rad51 in homologous recombination. The identification and characterization of two new Fanconi proteins having helicase motifs, FANCM and FANCJ/BRIP1/BACH1, implicates the FANC nuclear core complex as a participant in recognizing or processing damaged DNA, and the BRIP1 helicase as acting independently of this complex.
Date: August 16, 2005
Creator: Thompson, L H
System: The UNT Digital Library
Data Analysis in the Twenty-First Century (open access)

Data Analysis in the Twenty-First Century

The 21st Century is characterized by complex multidisciplinary problems accompanied by massive datasets. 'We are drowning in data, but starving for knowledge', as the volumes of many commercial, industrial and scientific datasets have exceeded the terabyte range and are approaching petabytes and beyond. Statistical methodology has long been employed to find useful and usable information in data. More recently, data mining has harnessed the power of computer technology to find useful and usable patterns in such massive datasets. Although several data mining journals have joined the established statistical journals, no single journal provides an integrated treatment of statistical analysis methodology and data mining technology, particularly when applied to the solution of practical problems. This absence and the needs expressed above motivated the inauguration of John Wiley's new Journal on Statistical Analysis and Data Mining. The goals of this interdisciplinary journal are to encourage collaborations across disciplines, communication of data mining and statistical techniques to both novices and experts involved in the analysis of data from practical problems, and a principled and productive evaluation of analyses and solutions. The journal specifically encourages submission of works that have statistical rigor in the analysis of data, incorporate the most appropriate algorithms from data …
Date: August 16, 2007
Creator: Goodman, A; Kamath, C & Kumar, V
System: The UNT Digital Library
The equation of state of liquid Flibe (open access)

The equation of state of liquid Flibe

Flibe (Li{sub 2}BeF{sub 4}) is a candidate material for the liquid blanket in the HYLIFE-2 fusion reactor. The thermodynamic properties of the material are important for the study of thermohydraulic behavior of the concept design, including the compressible analysis of the blanket isochoric heating problem and resulting jet breakup. The equation of state provides the relationship between all the thermodynamic properties. Previously, a soft sphere model of liquid equation of state was used for describing a number of liquid metals. In this paper we have fitted the available experimental data for liquid Flibe with a modified soft sphere model. 5 refs.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
System: The UNT Digital Library
The analysis of the Flibe jets in HYLIFE-II (open access)

The analysis of the Flibe jets in HYLIFE-II

In the HYLIFE-2 Inertial Confinement Fusion reactor, an array of Flibe (Li{sub 2}BeFe{sub 4}) jets is designed to protect the chamber from the fusion radiation. During the fusion pulse the Flibe jets sustain an instantaneous neutron and X-ray heating. The high energy neutrons from fusion can penetrate deep into the Flibe jets and the sudden increase in internal energy can induce a great pressure rise inside the jets. The subsequent relaxation of the jets is important for the reactor design, because the configuration of the jets will control the subsequent impact forces of vapor and liquid on the reactor chamber wall. The calculations for the lithium jets in the HYLIFE-1 reactor were done previously by using a compressible flow model with a soft sphere equation of state for lithium. A similar equation of state model for Flibe was recently developed. This model allows us to use the same compressible analysis code to calculate the pressure field in the Flibe jets and to estimate the upper bound of the Flibe tension limit. With these results we can analyze the mechanisms of jet relaxation and breakup. 4 refs., 1 fig.
Date: August 16, 1991
Creator: Chen, Xiang M.; Schrock, V.E. & Peterson, P.F.
System: The UNT Digital Library
Some programming aids for the DEC PDP-10 (open access)

Some programming aids for the DEC PDP-10

A simplified system has been written to help in FORTRAN programming of physics and mathematical problems. The system is described in Appendix A. A magnetic tape has been made of the complete system as used on the DEC-10 by M-Division for Magnetic Fusion related calculations. The system turns out to use many of the locally developed goodies, such as the TEDI text editor, the TV80 graphics system, and Tektronix 4012 videos. The facilities are briefly described in the HLP files on the tape.
Date: August 16, 1979
Creator: McNamara, B.
System: The UNT Digital Library
Development of a high-efficiency, high-performance air filter medium (open access)

Development of a high-efficiency, high-performance air filter medium

A unique high-efficiency particulate air (HEPA) filter medium has been developed for applications in high temperature and high pressure environments. This filter medium is a composite made from quartz and stainless-steel fibers that have been sintered together. The composite medium has the same efficiency and pressure drop as standard HEPA glass media, but has four times the tensile strength and can operate continuously at temperatures up to 500/degree/C. In a conventional HEPA, the binder burns out above 250/degree/C and the medium loses its strength; our composite filter medium has no comparable loss of strength even at 500/degree/C. 8 refs., 8 figs., 1 tab.
Date: August 16, 1988
Creator: Bergman, W. & Sawyer, S.R.
System: The UNT Digital Library
Deep inelastic muon scattering at 500 and 100 GeV (open access)

Deep inelastic muon scattering at 500 and 100 GeV

A description of experiment E665 at Fermilab is given. Data were taken at muon energies of 500 and 100 GeV and with targets of H/sub 2/, D/sub 2/, and Xe. Initial analysis of the first run's data has commenced. Physics topics addressed by the experiment are given. 1 ref., 1 fig., 1 tab.
Date: August 16, 1988
Creator: Wolbers, S.
System: The UNT Digital Library
Oriented Logging Tools at the Nevada Test Site (open access)

Oriented Logging Tools at the Nevada Test Site

Large-diameter boreholes drilled at the Nevada Test Site for the Department of Energy frequently exhibit an elongation in response to the regional stress field. Single-axis, decentralized logging tools invariably migrate to the long axis of the hole while logging. The long axis is the roughest and is more frequently washed out. The design of these tools therefore ensures that the worst possible side of the borehole is being logged. A new line of geophysical logging tools has been developed at the suggestion of EG and G, Energy Measurements, Inc., to overcome the effect of borehole elongation. A pair of orienting arms set at 90/sup 0/ to the measurement axis effectively turn the tool so that measurements are always recorded on the smoother, short side of the borehole. 3 refs., 5 figs.
Date: August 16, 1985
Creator: Clark, S. R.
System: The UNT Digital Library
In-situ Studies of Highly Charged Ions at the LLNL EBIT (open access)

In-situ Studies of Highly Charged Ions at the LLNL EBIT

The properties of highly charged ions and their interaction with electrons and atoms is being studied in-situ at the LLNL electron beam ion traps, EBIT-II and SuperEBIT. Spectroscopic measurements provide data on electron-ion and ion-atom interactions as well as accurate transition energies of lines relevant for understanding QED, nuclear magnetization, and the effects of relativity on complex, state-of-the-art atomic calculations.
Date: August 16, 2001
Creator: Beiersdorfer, P
System: The UNT Digital Library
Does Mixing Make Residential Ventilation More Effective? (open access)

Does Mixing Make Residential Ventilation More Effective?

Ventilation dilutes or removes indoor contaminants to reduce occupant exposure. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. The total ventilation rate is the most important factor in determining the exposure of occupants to given sources, but the zone- specific distribution of exhaust and supply air, and the mixing of ventilation air can have significant roles. Different types of ventilation systems will provide different amounts of mixing depending on several factors such as air leakage through the building envelope, air distribution systems and the location of sources and occupants. This paper reports recent results of investigations to determine the impact that air mixing has on exposures of residential occupants to prototypical contaminants of concern. Evaluations of existing field measurements and simulations reported in the literature are combined with new analyses to provide an integrated overview of the topic. The results show that for extreme cases additional mixing can be a significant factor but for typical homes looking at average exposures mixing is not helpful and can even make exposures worse.
Date: August 16, 2010
Creator: Sherman, Max & Walker, Iain
System: The UNT Digital Library
Insights on the Cuprate High Energy Anomaly Observed in ARPES (open access)

Insights on the Cuprate High Energy Anomaly Observed in ARPES

Recently, angle-resolved photoemission spectroscopy has been used to highlight an anomalously large band renormalization at high binding energies in cuprate superconductors: the high energy 'waterfall' or high energy anomaly (HEA). The anomaly is present for both hole- and electron-doped cuprates as well as the half-filled parent insulators with different energy scales arising on either side of the phase diagram. While photoemission matrix elements clearly play a role in changing the aesthetic appearance of the band dispersion, i.e. creating a 'waterfall'-like appearance, they provide an inadequate description for the physics that underlies the strong band renormalization giving rise to the HEA. Model calculations of the single-band Hubbard Hamiltonian showcase the role played by correlations in the formation of the HEA and uncover significant differences in the HEA energy scale for hole- and electron-doped cuprates. In addition, this approach properly captures the transfer of spectral weight accompanying doping in a correlated material and provides a unifying description of the HEA across both sides of the cuprate phase diagram. We find that the anomaly demarcates a transition, or cross-over, from a quasiparticle band at low binding energies near the Fermi level to valence bands at higher binding energy, assumed to be of strong …
Date: August 16, 2011
Creator: Moritz, Brian
System: The UNT Digital Library
Ultrafast x-ray diagnostics for laser fusion experiments (open access)

Ultrafast x-ray diagnostics for laser fusion experiments

Temporally, spectrally, and spatially resolved x-ray emission diagnostics are important tools in the study of the heating and compression of laser fusion targets by sub-nanosecond laser pulses. The use of the Livermore 15 psec resolution x-ray streak camera to make such measurements is reviewed. Temporal histories of spectrally resolved x-ray emission in the 1 to 10 keV range have been obtained. These data have served to further define the x-ray streak camera as a quantative diagnostic tool and have also provided data relating to the absorption and compression phases of laser heating. The x-ray streak camera has been used in conjunction with a specially designed pinhole imaging system to temporally record images of laser compressed targets with a spatial resolution of approximately 6 ..mu..m. Implosion characteristics are presented for experiments with glass microshell targets. The concept, development, and testing of an ultrafast framing camera for full two-dimensional time resolved imaging is discussed. A prototype camera, based on the image dissection-restoration concept, has achieved an approximately 200 psec frame period with a resolution of 50 ..mu..m.
Date: August 16, 1976
Creator: Coleman, L. W.
System: The UNT Digital Library
Wake potentials of the ILC Interaction Region (open access)

Wake potentials of the ILC Interaction Region

The vacuum chamber of the ILC Interaction Region (IR) is optimized for best detector performance. It has special shaping to minimize additional backgrounds due to the metal part of the chamber. Also, for the same reason this thin vacuum chamber does not have water cooling. Therefore, small amounts of power, which may be deposited in the chamber, can be enough to raise the chamber to a high temperature. One of the sources of 'heating' power is the electromagnetic field of the beam. This field diffracts by non-regularities of the beam pipe and excites free-propagating fields, which are then absorbed by the pipe wall. In addition we have a heating power of the image currents due to finite conductivity of the metallic wall. We will discuss these effects as updating the previous results. The conclusions of this report are: (1) The amount of the beam energy loss in IR is almost equal to the energy loss in one ILC (TESLA) accelerating cryo-module; (2) Addition energy spread at IR is very small; (3) Spectrum of the wake fields is limited 300 GHz; (4) Average power of the wake fields excited in IR is 30 W for nominal ILC parameters; and (5) Pulse …
Date: August 16, 2011
Creator: Novokhatski, A.
System: The UNT Digital Library
2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement (open access)

2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement

We introduce a duality between two-dimensional XY-spin models with symmetry-breaking perturbations and certain four-dimensional SU(2) and SU(2) = Z{sub 2} gauge theories, compactified on a small spatial circle R{sup 1,2} x S{sup 1}, and considered at temperatures near the deconfinement transition. In a Euclidean set up, the theory is defined on R{sup 2} x T{sup 2}. Similarly, thermal gauge theories of higher rank are dual to new families of 'affine' XY-spin models with perturbations. For rank two, these are related to models used to describe the melting of a 2d crystal with a triangular lattice. The connection is made through a multi-component electric-magnetic Coulomb gas representation for both systems. Perturbations in the spin system map to topological defects in the gauge theory, such as monopole-instantons or magnetic bions, and the vortices in the spin system map to the electrically charged W-bosons in field theory (or vice versa, depending on the duality frame). The duality permits one to use the two-dimensional technology of spin systems to study the thermal deconfinement and discrete chiral transitions in four-dimensional SU(N{sub c}) gauge theories with n{sub f} {ge} 1 adjoint Weyl fermions.
Date: August 16, 2012
Creator: Anber, Mohamed M.; Poppitz, Erich; U., /Toronto; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept. /San Francisco State U.
System: The UNT Digital Library
Shock-Compressed Diamond: Melt, Insulator-Conductor and Polymeric-Atomic Transitions (open access)

Shock-Compressed Diamond: Melt, Insulator-Conductor and Polymeric-Atomic Transitions

Temperatures measured on the shock-Hugoniot of diamond reveal melting between 650 ({+-} 60) GPa and 9000 ({+-} 800) K and 1090 ({+-} 50) GPa and 8400 ({+-} 800) K, with a heat of fusion of {approx} 25 {+-} 10 kJ/mole and a negative Clapeyron slope {partial_derivative}T/{partial_derivative}P|{sub melt} = -5 {+-} 3 K/GPa. Thus, the fluid is denser than the compressed solid, and optical reflectivity measurements show it to be metallic. Hugoniot-temperature measurements extending to over 4000 GPa (40 Mbar) and 115,000 K suggest de-polymerization of a dense covalently-bonded fluid to an atomic state between 10,000 and 30,000 K. These experimental results indicate that carbon present deep inside planets such as Uranus and Neptune could be solid for through-going convection, whereas stable stratification would allow for the presence of fluid metallic carbon at depth; in either case, the presence of carbon could potentially affect planetary seismic normal modes.
Date: August 16, 2007
Creator: Eggert, J; Hicks, D G; Celliers, P M; Bradley, D K; McWilliams, R S; Jeanloz, R et al.
System: The UNT Digital Library
A Fisheye Lens as a Photonic Doppler Velocimetry Probe (open access)

A Fisheye Lens as a Photonic Doppler Velocimetry Probe

These presentation visuals report an instrument that, by use of a fish-eye lens, generates a beat signal using fiber mixing of unshifted light with Doppler-shifted light and measures the beat frequency. Ray trace diagrams are shown to illustrate advantages and disadvantages. The authors find their instrument has a long tracking distance, and large angle coverage. Index matching eases assembly, reduces return loss and flattens the field.
Date: August 16, 2012
Creator: Frogget, B. C.
System: The UNT Digital Library
Search for Dark Matter Satellites Using the FERMI-LAT (open access)

Search for Dark Matter Satellites Using the FERMI-LAT

Numerical simulations based on the {Lambda}CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the {gamma}-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard {gamma}-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on {gamma}-ray spectra consistent with WIMP annihilation through the b{bar b} channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the b{bar b} channel.
Date: August 16, 2012
Creator: Ackermann, M.; Albert, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D. et al.
System: The UNT Digital Library
Fiber array technique for subnanosecond x-ray framing camera (open access)

Fiber array technique for subnanosecond x-ray framing camera

A subnanosecond x-ray framing camera technique employing a fiber optics image dissector coupled to a 10 ps optical streak camera will be described. The output data from the streak camera can be reduced from photographic film or directly couple into a SEC Vidicon camera for immediate computer decoding of each scan line into a two dimensional picture. The use of the new subnanosecond plastic scintillator in front of the fiber optics dissector will also be discussed. The paper will include (1) the description of the basic principle, (2) fiber optics's image dissector construction, (3) time resolution considerations, and (4) experimental data on a prototype 7 by 7 array.
Date: August 16, 1976
Creator: Cheng, J. C.; Multhauf, L. G. & Tripp, G. R.
System: The UNT Digital Library
Discursive Deployments: Mobilizing Support for Municipal and Community Wireless Networks in the U.S. (open access)

Discursive Deployments: Mobilizing Support for Municipal and Community Wireless Networks in the U.S.

This paper examines Municipal Wireless (MW) deployments in the United States. In particular, the interest is in understanding how discourse has worked to mobilize widespread support for MW networks. We explore how local governments discursively deploy the language of social movements to create a shared understanding of the networking needs of communities. Through the process of"framing" local governments assign meaning to the MW networks in ways intended to mobilize support anddemobilize opposition. The mobilizing potential of a frame varies and is dependent on its centrality and cultural resonance. We examine the framing efforts of MW networks by using a sample of Request for Proposals for community wireless networks, semi-structured interviews and local media sources. Prominent values that are central to a majority of the projects and others that are culturally specific are identified and analyzed for their mobilizing potency.
Date: August 16, 2008
Creator: Alvarez, Rosio & Rodriguez, Juana Maria
System: The UNT Digital Library