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Use of AERIN code for determining internal doses of transuranic isotopes (open access)

Use of AERIN code for determining internal doses of transuranic isotopes

The AERIN computer code is a mathematical expression of the ICRP Lung Model. The code was developed at the Lawrence Livermore National Laboratory to compute the body organ burdens and absorbed radiation doses resulting from the inhalation of transuranic isotopes and to predict the amount of activity excreted in the urine and feces as a function of time. Over forty cases of internal exposure have been studied using the AERIN code. The code, as modified, has proven to be extremely versatile. The case studies presented demonstrate the excellent correlation that can be obtained between code predictions and observed bioassay data. In one case study a discrepancy was observed between an in vivo count of the whole body and the application of the code using urine and fecal data as input. The discrepancy was resolved by in vivo skull counts that showed the code had predicted the correct skeletal burden.
Date: June 13, 1980
Creator: King, W.C.
System: The UNT Digital Library
Textbooks Weighing you Down? Check out our E-Readers (open access)

Textbooks Weighing you Down? Check out our E-Readers

Article discussing a project by the UNT Libraries to purchase e-book readers for students purchasing digital textbooks.
Date: June 13, 2014
Creator: Brannon, Sian & Sears, Suzanne
System: The UNT Digital Library
Spatiotemporal variations in growing season exchanges of CO2, H2O,and sensible heat in agricultural fields of the Southern GreatPlains (open access)

Spatiotemporal variations in growing season exchanges of CO2, H2O,and sensible heat in agricultural fields of the Southern GreatPlains

Climate, vegetation cover, and management create fine-scaleheterogeneity in unirrigated agricultural regions, with important but notwell-quantified consequences for spatial and temporal variations insurface CO2, water, and heat fluxes. We measured eddy covariance fluxesin seven agricultural fields--comprising winter wheat, pasture, andsorghum--in the U.S. Southern Great Plains (SGP) during the 2001-2003growing seasons. Land-cover was the dominant source of variation insurface fluxes, with 50-100 percent differences between fields planted inwinter-spring versus fields planted in summer. Interannual variation wasdriven mainly by precipitation, which varied more than two-fold betweenyears. Peak aboveground biomass and growing-season net ecosystem exchange(NEE) of CO2 increased in rough proportion to precipitation. Based on apartitioning of gross fluxes with a regression model, ecosystemrespiration increased linearly with gross primary production, but with anoffset that increased near the time of seed production. Because theregression model was designed for well-watered periods, it successfullyretrieved NEE and ecosystem parameters during the peak growing season,and identified periods of moisture limitation during the summer. Insummary, the effects of crop type, land management, and water limitationon carbon, water, and energy fluxes were large. Capturing the controllingfactors in landscape scale models will be necessary to estimate theecological feedbacks to climate and other environmental impactsassociated with changing human needs for agricultural production of …
Date: June 13, 2007
Creator: Fischer, Marc L.; Billesbach, David P.; Berry, Joseph A.; Riley,William J. & Torn, Margaret S.
System: The UNT Digital Library
CHARACTERIZATION OF A HIGH CURRENT INDUCTION ACCELERATOR ELECTRON BEAM VIA OPTICAL TRANSITION RADIATION FROM DIELECTRIC FOILS (open access)

CHARACTERIZATION OF A HIGH CURRENT INDUCTION ACCELERATOR ELECTRON BEAM VIA OPTICAL TRANSITION RADIATION FROM DIELECTRIC FOILS

Traditionally, thin metal foils are employed for optical transition radiation (OTR) beam diagnostics but the possibility of shorting accelerator insulating surfaces and modifying accelerating fields are concerns. The successful utilization of dielectric foils in place of metal ones could alleviate these issues but necessitates more understanding of the OTR data for inferring desired beam parameters because of the dielectric's finite permittivity. Additionally, the temperature dependence of the relevant foil parameters due to beam heating should be accounted for. Here, we present and discuss sample synthetic diagnostic results of Kapton OTR spot-size measurements from the Flash X-Ray (FXR) accelerator which studies these and sightline effects. These simulations show that in some cases, the observed spot-sizes and radii are noticeably larger than the beam radii.
Date: June 13, 2007
Creator: Tang, V; Brown, C & Houck, T
System: The UNT Digital Library
Machine-Detector Interface Issues for the ILCPolarimeters (open access)

Machine-Detector Interface Issues for the ILCPolarimeters

This note examines several Machine-Detector Interface (MDI) issues for the Compton polarimeters in the Beam Delivery System of the International Linear Collider (ILC), including (1) alignment tolerances, (2) impact of crossing angle and IR magnets on spin alignment, (3) Z-pole operation, and (4) costs and conventional facilities.
Date: June 13, 2008
Creator: Woods, Mike
System: The UNT Digital Library
SHOCK INITIATION EXPERIMENTS ON PBX 9501 EXPLOSIVE AT PRESSURES BELOW 3 GPa WITH ASSOCIATED IGNITION AND GROWTH MODELING (open access)

SHOCK INITIATION EXPERIMENTS ON PBX 9501 EXPLOSIVE AT PRESSURES BELOW 3 GPa WITH ASSOCIATED IGNITION AND GROWTH MODELING

Shock initiation experiments on the explosive PBX 9501 (95% HMX, 2.5% estane, and 2.5% nitroplasticizer by weight) were performed at pressures below 3 GPa to obtain in-situ pressure gauge data, run-distance-to-detonation thresholds, and Ignition and Growth modeling parameters. Propellant driven gas guns (101 mm and 155 mm) were utilized to initiate the PBX 9501 explosive with manganin piezoresistive pressure gauge packages placed between sample slices. The run-distance-to-detonation points on the Pop-plot for these experiments showed agreement with previously published data and Ignition and Growth modeling parameters were obtained with a good fit to the experimental data. This parameter set will allow accurate code predictions to be calculated for safety scenarios in the low-pressure regime (below 3 GPa) involving PBX 9501 explosive.
Date: June 13, 2007
Creator: Chidester, S K; Thompson, D G; Vandersall, K S; Idar, D J; Tarver, C M; Garcia, F et al.
System: The UNT Digital Library
DYNAMIC LOADING OF TEFLON AT 200?C (open access)

DYNAMIC LOADING OF TEFLON AT 200?C

Dynamic loading experiments were performed on inert Teflon (Polytetrafluoroethylene) samples, initially heated to the temperature of 200 C, to test its behavior under these conditions for its use in other heated experiments. Tests were performed in the 100 mm diameter bore propellant driven gas gun with piezo-resistive manganin pressure gauges imbedded into the samples to measure loading pressures. Experimental data provided new information on the shock velocity - particle velocity relationship for the heated material and showed no adverse effect of temperature on the insulating properties of the material.
Date: June 13, 2007
Creator: Urtiew, P A; Forbes, J W; Tarver, C M; Vandersall, K S & Garcia, F
System: The UNT Digital Library
The US Support Program to IAEA Safeguards Priority of Containment and Surveillance (open access)

The US Support Program to IAEA Safeguards Priority of Containment and Surveillance

The United States Support Program (USSP) priority for containment and surveillance (US) focuses on maintaining or improving the reliability and cost-effectiveness of C/S systems for IAEA safeguards, expanding the number of systems that are unattended and remotely monitored, and developing verification methods that help streamline the on-site inspection process. Existing IAEA C/S systems have evolved to become complex, integrated systems, which may include active seals, nondestructive assay (NDA) instruments, video cameras, and other sensors. These systems operate autonomously. They send analytical data to IAEA headquarters where it can be reviewed. These systems present challenges to the goals of improved system performance, standardization, reliability, maintainability, documentation, and cost effectiveness. One critical lesson from past experiences is the need for cooperation and common objectives among the IAEA, the developer, and the facility operator, to create a successful, cost effective system. Recent USSP C/S activities include Rokkasho Reprocessing Plant safeguard systems, production of a new shift register, numerous vulnerability assessments of C/S systems, a conduit monitoring system which identifies tampering of IAEA conduit deployed in the field, fiber optic seal upgrades, unattended monitoring system software upgrades, next generation surveillance system which will upgrade existing camera systems, and support of the IAEA's development of …
Date: June 13, 2008
Creator: Diaz,R.A.
System: The UNT Digital Library
A brief review of the intensity of lines 3C and 3D in neon-like Fe XVII (open access)

A brief review of the intensity of lines 3C and 3D in neon-like Fe XVII

X-ray emission from neon-like Fe XVII has been measured with high-resolution spectrometers from laboratory or celestial sources for nearly seven decades. Two of the strongest lines regularly identified in these spectra are the {sup 1}P{sub 1} {yields} {sup 1}S{sub 0} resonance, and {sup 3}D{sub 1} {yields} {sup 1}S{sub 0} intercombination line, known as 3C and 3D, respectively. This paper gives a brief overview of measurements of the intensities of the lines 3C and 3D from laboratory and celestial sources, and their comparison to model calculations, with an emphasis on measurements completed using an electron beam ion trap. It includes a discussion of the measured absolute cross sections compared to results from modern atomic theory calculations, as well as the diagnostic utility of the relative intensity, R = I{sub 3C}/I{sub 3D}, as it applies to the interpretation of spectra measured from the Sun and extra-Solar sources.
Date: June 13, 2007
Creator: Brown, G V
System: The UNT Digital Library
Mechanical Design of the LSST Camera (open access)

Mechanical Design of the LSST Camera

The LSST camera is a tightly packaged, hermetically-sealed system that is cantilevered into the main beam of the LSST telescope. It is comprised of three refractive lenses, on-board storage for five large filters, a high-precision shutter, and a cryostat that houses the 3.2 giga-pixel CCD focal plane along with its support electronics. The physically large optics and focal plane demand large structural elements to support them, but the overall size of the camera and its components must be minimized to reduce impact on the image stability. Also, focal plane and optics motions must be minimized to reduce systematic errors in image reconstruction. Design and analysis for the camera body and cryostat will be detailed.
Date: June 13, 2008
Creator: Nordby, Martin; Bowden, Gordon; Foss, Mike; Guiffre, Gary; Ku, John & Schindler, Rafe
System: The UNT Digital Library
Sequencing and Analysis of Neanderthal Genomic DNA (open access)

Sequencing and Analysis of Neanderthal Genomic DNA

Recovery and analysis of multiple Neanderthal autosomalsequences using a metagenomic approach reveals that modern humans andNeanderthals split ~;400,000 years ago, without significant evidence ofsubsequent admixture.
Date: June 13, 2006
Creator: Noonan, James P.; Coop, Graham; Kudaravalli, Sridhar; Smith,Doug; Krause, Johannes; Alessi, Joe et al.
System: The UNT Digital Library
Chandra Reveals Twin X-ray Jets in the Powerful FR-II Radio Galaxy 3C353 (open access)

Chandra Reveals Twin X-ray Jets in the Powerful FR-II Radio Galaxy 3C353

We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-ray Observatory. 3C 353's two 4-inch wide and 2-feet long jets allow us to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the sub-arcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the jet and the counterjet, the terminal jet regions (hotspots), and one radio lobe. We show that the detection of the X-ray emission associated with the radio knots and counterknots, which is most likely non-thermal in origin, puts several crucial constraints on the X-ray emission mechanisms in powerful large-scale jets of quasars and FR II sources. In particular, we show that this detection is inconsistent with the inverse-Compton model proposed in the literature, and instead implies a synchrotron origin of the X-ray jet photons. We also find that the width of the X-ray counterjet is possibly narrower than that measured in radio bands, that the radio-to-X-ray flux ratio decreases systematically downstream along the jets, and that there are substantial …
Date: June 13, 2008
Creator: Kataoka, J.; Stawarz, L.; Harris, D.E.; Siemiginowska, A.; Ostrowski, M.; Swain, M.R. et al.
System: The UNT Digital Library
The work function of sub-monolayer cesium-covered gold: A photoelectronspectroscopy study (open access)

The work function of sub-monolayer cesium-covered gold: A photoelectronspectroscopy study

Using visible and X-ray photoelectron spectroscopy we measured the work function of a Au(111) surface at a well-defined sub-monolayer coverage of Cs. For a Cs coverage producing a photoemission maximum with a He-Ne laser, the work function is 1.61 {+-} 0.08 eV consistent with previous assumptions used to analyze vibrationally promoted electron emission. A discussion of possible Cs layer structures is also presented.
Date: June 13, 2008
Creator: LaRue, J. L.; White, J. D.; Nahler, N. H.; Liu, Z.; Sun, Y.; Pianetta, P. A. et al.
System: The UNT Digital Library
The US Support Program to IAEA Safeguards Priority of Training and Human Resources (open access)

The US Support Program to IAEA Safeguards Priority of Training and Human Resources

The U.S. Support Program to IAEA Safeguards (USSP) priority of training and human resources is aimed at providing the Department of Safeguards with an appropriate mixture of regular staff and extrabudgetary experts who are qualified to meet the IAEA's technical needs and to provide personnel with appropriate instruction to improve the technical basis and specific skills needed to perform their job functions. The equipment and methods used in inspection activities are unique, complex, and evolving. New and experienced safeguards inspectors need timely and effective training to perform required tasks and to learn new skills prescribed by new safeguards policies or agreements. The role of the inspector has changed from that of strictly an accountant to include that of a detective. New safeguards procedures are being instituted, and therefore, experienced inspectors must be educated on these new procedures. The USSP also recognizes the need for training safeguards support staff, particularly those who maintain and service safeguards equipment (SGTS), and those who perform information collection and analysis (SGIM). The USSP is committed to supporting the IAEA with training to ensure the effectiveness of all staff members and will continue to offer its assistance in the development and delivery of basic, refresher, and …
Date: June 13, 2008
Creator: Queirolo,A.
System: The UNT Digital Library
Measurements of the asymmetric, dynamic sheath around a pulse biased sphere immersed in flowing metal plasma (open access)

Measurements of the asymmetric, dynamic sheath around a pulse biased sphere immersed in flowing metal plasma

A long-probe technique was utilized to record the expansion and retreat of the dynamic sheath around a spherical substrate immersed in pulsed cathode arc metal plasma. Positively biased, long cylindrical probes were placed on the side and downstream of a negatively pulsed biased stainless steel sphere of 1" (25.4 mm) diameter. The amplitude and width of the negative high voltage pulses (HVP) were 2 kV, 5 kV, 10 kV, and 2 mu s, 4 mu s, 10 mu s, respectively. The variation of the probe (electron) current during the HVP is a direct measure for the sheath expansion and retreat. Maximum sheath sizes were determined for the different parameters of the HVP. The expected rarefaction zone behind the biased sphere (wake) due to the fast plasma flow was clearly established and quantified.
Date: June 13, 2008
Creator: Anders, Andre; Wu, Hongchen & Anders, Andre
System: The UNT Digital Library
Transfer factors for assessing the dose from radionuclides in agricultural products (open access)

Transfer factors for assessing the dose from radionuclides in agricultural products

Transfer factors to predict the environmental transport of radionuclides through terrestrial foodchains to man were derived from the literature for radionuclides associated with the nuclear fuel cycle. We present updated transfer coefficients to predict the concentration of a radionuclide in cow's milk and other animal products and concentration factors (CF) to predict the concentration in a food or feed crop from that in soil. Where possible we note the variation of the transfer factor with physical and chemical form of the radionuclide and environmental factors, and characterize the distribution and uncertainty in the estimate. The updated transfer factors are compared with those listed in regulatory guides. The new estimates lead to recommended changes (both increases and decreases) in the listed transfer coefficients for milk and meat and to the suggested practice of adopting multiple soil-to-plant CF's that vary with the type of crop and soil in the place of a single generic CF to predict the concentration of a radionuclide in a crop from that in soil. The updated transfer factors will be useful to assess the dose from radionuclides released from nuclear facilities and evaluating compliance with regulations governing the release of radionuclides.
Date: June 13, 1979
Creator: Ng, Y.C.; Colsher, C.S. & Thompson, S.E.
System: The UNT Digital Library
Fusion: the power source of the future Inertial Confinement Option (open access)

Fusion: the power source of the future Inertial Confinement Option

Among the various energy options opened to man, fusion appears particularly attractive since fuel is plentiful, cheap, and universally available, the reaction is self quenching, produces in itself no radioactive wastes and radiation hazards are minimum. However, creating on earth conditions emulating the sun is not as easy task. Two significantly different approaches to obtaining the necessary conditions are being actively pursued and both have shown encouraging progress in the past few years. Magnetic confinement will be discussed in the next paper. Inertial confinement fusion is progressing towards scientific breakeven in the 1980's. High yield targets have been successfully imploded proving the feasibility of thermonuclear burn. High densities have recently been achieved using glass lasers as drivers. Power plants using fusion sources are being studied and could become operational in the early 2000's.
Date: June 13, 1979
Creator: Rupert, V.
System: The UNT Digital Library
Method of calculating test leakage rate for a spent fuel cask (open access)

Method of calculating test leakage rate for a spent fuel cask

This report presents a method for calculating containment test leakage rates of radionuclides from an example spent fuel cask. Three releasable radioactive sources are considered: residual contamination in the cask cavity, crud on the fuel elements, and the radionuclides within the fuel rods. The ANSI N14.5 standard is used to calculate the test leakage rates from the maximum permissible releases determined from 10 CFR 71 containment requirements. 6 refs., 2 tabs.
Date: June 13, 1990
Creator: Fischer, L. E.
System: The UNT Digital Library
[The Dallas Morning News articles, June 13, 1994] (open access)

[The Dallas Morning News articles, June 13, 1994]

An article clipping from The Dallas Morning News article 'A rosier picture' written by Larry Bleiberg. The piece covers the planned rebuilding of the Dallas ISD fine arts program through several years of revamped funding and building up of curriculum.
Date: June 13, 1994
Creator: Bleiberg, Larry
System: The UNT Digital Library
Multivariate Clustering of Large-Scale Scientific Simulation Data (open access)

Multivariate Clustering of Large-Scale Scientific Simulation Data

Simulations of complex scientific phenomena involve the execution of massively parallel computer programs. These simulation programs generate large-scale data sets over the spatio-temporal space. Modeling such massive data sets is an essential step in helping scientists discover new information from their computer simulations. In this paper, we present a simple but effective multivariate clustering algorithm for large-scale scientific simulation data sets. Our algorithm utilizes the cosine similarity measure to cluster the field variables in a data set. Field variables include all variables except the spatial (x, y, z) and temporal (time) variables. The exclusion of the spatial dimensions is important since ''similar'' characteristics could be located (spatially) far from each other. To scale our multivariate clustering algorithm for large-scale data sets, we take advantage of the geometrical properties of the cosine similarity measure. This allows us to reduce the modeling time from O(n{sup 2}) to O(n x g(f(u))), where n is the number of data points, f(u) is a function of the user-defined clustering threshold, and g(f(u)) is the number of data points satisfying f(u). We show that on average g(f(u)) is much less than n. Finally, even though spatial variables do not play a role in building clusters, it …
Date: June 13, 2003
Creator: Eliassi-Rad, T & Critchlow, T
System: The UNT Digital Library
Qualification of Safety-Related Software in Nuclear Power Plants (open access)

Qualification of Safety-Related Software in Nuclear Power Plants

Digital instrumentation and control systems have the potential of offering significant benefits over traditional analog systems in Nuclear Power Plant safety systems, but there are also significant difficulties in qualifying digital systems to the satisfaction of regulators. Digital systems differ in fundamental ways from analog systems. New methods for safety qualification, which take these differences into account, would ease the regulatory cost and promote use of digital systems. This paper offers a possible method for assisting in the analysis of digital system software, as one step in an improved qualification process.
Date: June 13, 2000
Creator: Johnson, G L
System: The UNT Digital Library
''The Incubation Period for Void Swelling and its Dependence on Temperature, Dose Rate, and Dislocation Structure Evolution'' (open access)

''The Incubation Period for Void Swelling and its Dependence on Temperature, Dose Rate, and Dislocation Structure Evolution''

Void swelling in structural materials used for nuclear reactors is characterized by an incubation period whose duration largely determines the usefulness of the material for core components. Significant evolution of the dislocation and void microstructures that control radiation-induced swelling can occur during this period. Thus, a theory of incubation must treat time-dependent void nucleation in combination with dislocation evolution, in which the sink strengths of voids and dislocations change in concert. We present theoretical results for void nucleation and growth including the time-dependent, self-consistent coupling of point defect concentrations to the evolution of both void populations and dislocation density. Simulations show that the incubation radiation dose is a strong function of the starting dislocation density and of the dislocation bias factors for vacancy and interstitial absorption. Irradiation dose rate and temperature also affect the duration of incubation. The results are in general agreement with experiment for high purity metals.
Date: June 13, 2002
Creator: Surh, M. P.; Sturgeon, J. B. & Wolfer, W. G.
System: The UNT Digital Library
The UA9 Experimental Layout (open access)

The UA9 Experimental Layout

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Date: June 13, 2012
Creator: Scandale, W.; Arduini, G.; Assmann, R.; Bracco, C.; Cerutti, F.; Christiansen, J. et al.
System: The UNT Digital Library
Branching Fraction Measurement of B to omega l nu decays (open access)

Branching Fraction Measurement of B to omega l nu decays

We present a measurement of the B{sup +} {yields} {omega}{ell}{sup +}{nu} branching fraction based on a sample of 467 million B{bar B} pairs recorded by the BABAR detector at the SLAC PEP-II e{sup +}e{sup -} collider. We observe 1041 {+-} 133 signal decays, corresponding to a branching fraction of {Beta}(B{sup +} {yields} {omega}{ell}{sup +}{nu}) = (1.15 {+-} 0.15 {+-} 0.12) x 10{sup -4}, where the first error is statistical and the second is systematic. The dependence of the decay rate on q{sup 2}, the momentum transfer squared to the lepton system, is compared to QCD predictions of the form factors based on a quark model and light-cone sum rules.
Date: June 13, 2012
Creator: Lees, J. P.; Poireau, V.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Palano, A. et al.
System: The UNT Digital Library