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INHALATION TOXICITY OF ZIRCONIUM COMPOUNDS. I. SHORT-TERM STUDIES (open access)

INHALATION TOXICITY OF ZIRCONIUM COMPOUNDS. I. SHORT-TERM STUDIES

A total of 270 animals of 5 species was exposed by inhalation to compounds of zirconium for 6 hours per day, 5 days per week. One group of animals was exposed to ZrO{sub 2} at an atmospheric concentration of 75 mg. Zr/m{sup 3} for 30 days; another, to 11 mg. Zr/m{sup 3} for 60 days. A third group was exposed to a mist of ZrCl{sub 4} at a level of 6 mg. Zr/m{sup 3} for 60 days. Zirconium oxide produced no significant changes in mortality, growth rate, blood nonprotein nitrogen or fibrinogen, urinary protein, hematological values or histological structure. Zirconium tetrachloride at 6 mg. Zr/m{sup 3} gave questionable changes in blood hemoglobin concentration and red cell counts of dogs and a slight increase in mortality of rats and guinea pigs. Inhaled zirconium compounds deposited primarily in the lung and pulmonary lymph node, with a fraction of a per cent in the bone and considerably less in the soft tissues. (auth)
Date: July 31, 1956
Creator: Spiegl, C. J.; Calkins, M. C.; DeVoldre, J. J.; Scott, J. K.; Steadman, L. T. & Stokinger, H. E.
Object Type: Report
System: The UNT Digital Library
Inertial Confinement Fusion quarterly report, January-March 1998, volume 8, number 2 (open access)

Inertial Confinement Fusion quarterly report, January-March 1998, volume 8, number 2

The coupling of laser light with plasmas is one of the key physics issues for the use of high-power lasers for inertial fusion, high-energy-density physics, and scientific stockpile stewardship. The coupling physics is extremely rich and challenging, particularly in the large plasmas to be accessed on the National Ignition Facility (NIF). The coupling mechanisms span the gamut from classical inverse bremsstrahlung absorption to a variety of nonlinear optical processes. These include stimulated Raman scattering (SRS) from electron plasma waves, stimulated Brillouin scattering (SBS) from ion sound waves, resonant decay into electron plasma and ion sound waves, and laser beam filamentation. These processes depend on laser intensity and produce effects such as changes in the efficiency and location of the energy deposition or generation of a component of very energetic electrons, which can preheat capsules. Coupling physics issues have an extremely high leverage. The coupling models are clearly very important ingredients for detailed calculations of laser-irradiated target behavior. Improved understanding and models enable a more efficient use of laser facilities, which becomes even more important as these facilities become larger and more expensive. Advances in the understanding also allow a more timely and cost-effective identification of new applications of high-power lasers, …
Date: March 31, 1998
Creator: Kruer, W
Object Type: Report
System: The UNT Digital Library
A Compton camera for spectroscopic imaging from 100 keV to 1 MeV (open access)

A Compton camera for spectroscopic imaging from 100 keV to 1 MeV

A review of spectroscopic imaging issues, applications, and technology is presented. Compton cameras based on solid state semiconductor detectors stands out as the best system for the nondestructive assay of special nuclear materials. A camera for this application has been designed based on an efficient specific purpose Monte Carlo code developed for this project. Preliminary experiments have been performed which demonstrate the validity of the Compton camera concept and the accuracy of the code. Based on these results, a portable prototype system is in development. Proposed future work is addressed.
Date: December 31, 1998
Creator: Earnhart, J. R. D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
RESEARCH ON GRAPHITE. Annual Report, April 1, 1963-March 31, 1964 (open access)

RESEARCH ON GRAPHITE. Annual Report, April 1, 1963-March 31, 1964

None
Date: October 31, 1965
Creator: Price, R.J. & White, J.L.
Object Type: Report
System: The UNT Digital Library
The oncogenic action of ionizing radiation on rat skin. Final progress report, May 1, 1990--April 30, 1992 (open access)

The oncogenic action of ionizing radiation on rat skin. Final progress report, May 1, 1990--April 30, 1992

The multistage theory of carcinogenesis specifies that cells progress to cancer through a series of discrete, irreversible genetic alterations, but data on radiation-induced cancer incidence in rat skin suggests that an intermediate repairable alteration may occur. Data are presented on cancer induction in rat skin exposed to an electron beam (LET=0.34 keV/{mu}), a neon ion beam (LET=45) or an argon ion beam (LET=125). The rats were observed for tumors at least 78 weeks with squamous and basal cell carcinomas observed. The total cancer yield was fitted by the quadratic equation, and the equation parameters were estimated by linear regression for each type of radiation. Analysis of the DNA from the electron-induced carcinomas indicated that K-ras and/or c-myc oncogenes were activated. In situ hybridization indicated that the cancers contain subpopulations of cells with differing amounts of c-myc and H-ras amplification. The results are consistent with the idea that ionizing radiation produces stable, carcinogenically relevant lesions via 2 repairable events at low LET and via a non-repairable linked event pathway at high LET; either pathway may advance the cell by 1 stage. The proliferative response of rat epidermis following exposure to ionizing radiation was quantified by injection of {sup 14}C-thymidine. The return …
Date: December 31, 1992
Creator: Burns, F. J. & Garte, S. J.
Object Type: Report
System: The UNT Digital Library
High beta capture and mirror confinement of laser produced plasmas. Semiannual report, July 31, 1972--January 31, 1973 (open access)

High beta capture and mirror confinement of laser produced plasmas. Semiannual report, July 31, 1972--January 31, 1973

None
Date: January 31, 1973
Creator: Haught, A.F.; Polk, D.H.; Woo, J.T.; Fader, W.J.; Tomlinson, R.G.; Haas, R.A. et al.
Object Type: Report
System: The UNT Digital Library
Vehicle to Grid Demonstration Project (open access)

Vehicle to Grid Demonstration Project

This report summarizes the activities and accomplishments of a two-year DOE-funded project on Grid-Integrated Vehicles (GIV) with vehicle to grid power (V2G). The project included several research and development components: an analysis of US driving patterns; an analysis of the market for EVs and V2G-capable EVs; development and testing of GIV components (in-car and in-EVSE); interconnect law and policy; and development and filing of patents. In addition, development activities included GIV manufacturing and licensing of technologies developed under this grant. Also, five vehicles were built and deployed, four for the fleet of the State of Delaware, plus one for the University of Delaware fleet.
Date: December 31, 2010
Creator: Kempton, Willett; Gardner, Meryl; Hidrue, Michael; Kamilev, Fouad; Kamboj, Sachin; Lilley, Jon et al.
Object Type: Report
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
Inversion of Head Wave Traveltimes for Three-Dimensional Planar Structure (open access)

Inversion of Head Wave Traveltimes for Three-Dimensional Planar Structure

Inversion of head wave arrival times for three-dimensional (3D) planar structure is formulated as a constrained parameter optimization problem, and solved via linear programming techniques. The earth model is characterized by a set of homogeneous and isotropic layers bounded by plane, dipping interfaces. Each interface may possess arbitrary strike and dip. Predicted data consists of traveltimes of critically refracted waves formed on the plane interfaces of the model. The nonlinear inversion procedure is iterative; an initial estimate of the earth model is refined until an acceptable match is obtained between observed and predicted data. Inclusion of a priori constraint information, in the form of inequality relations satisfied by the model parameters, assists the algorithm in converging toward a realistic solution. Although the 3D earth model adopted for the inversion procedure is simple, the algorithm is quite useful in two particular contexts: (i) it can provide an initial model estimate suitable for subsequent improvement by more general techniques (i.e., traveltime tomography), and (ii) it is an effective analysis tool for investigating the power of areal recording geometries for detecting and resolving 3D dipping planar structure.
Date: March 31, 1999
Creator: Aldridge, D. F. & Oldenburg, D. W.
Object Type: Article
System: The UNT Digital Library
Ultra-High Intensity Proton Accelerators and their Applications (open access)

Ultra-High Intensity Proton Accelerators and their Applications

The science and technology of proton accelerators have progressed considerably in the past three decades. Three to four orders of magnitude increase in both peak intensity and average flux have made it possible to construct high intensity proton accelerators for modern applications, such as: spallation neutron sources, kaon factory, accelerator production of tritium, energy amplifier and muon collider drivers. The accelerator design focus switched over from intensity for synchrotrons, to brightness for colliders to halos for spallation sources. An overview of this tremendous progress in both accelerator science and technology is presented, with special emphasis on the new challenges of accelerator physics issues such as: H(-) injection, halo formation and reduction of losses.
Date: December 31, 1997
Creator: Weng, W. T.
Object Type: Article
System: The UNT Digital Library
Final Report U.S. Department of Energy Joint Inversion of Geophysical Data for Site Characterization and Restoration Monitoring (open access)

Final Report U.S. Department of Energy Joint Inversion of Geophysical Data for Site Characterization and Restoration Monitoring

The purpose of this project was to conduct basic research leading to significant improvements in the state-of-the-art of geophysical imaging of the shallow subsurface. Geophysical techniques are commonly used for underground imaging for site characterization and restoration monitoring. in order to improve subsurface imaging, the objective was to develop improved methods for interpreting geophysical data collected in the field, by developing better methods for relating measured geophysical properties, such as seismic velocity and electrical conductivity, to hydrogeology parameters of interest such as porosity, saturation, and soil composition. They met the objectives using an approach that combined laboratory experiments, comparison to available field data, rock physics theories, and modeling, to find relationships between geophysical measurements, hydrogeological parameters and soil composition. The primary accomplishments of this project in the last year (FY99) were that they completed the laboratory measurements of ultrasonic velocities in soils at low pressures and the measurements of complex electrical conductivity in those same soils; they used x-ray computed microtomography to image the microstructure of several soil samples; they used rock physics theories and modeling to relate the geophysical measurements to the microstructure and hydrological properties; they developed a theoretical technique for relating compressional and shear wave velocities to …
Date: July 31, 2000
Creator: Berge, P. A.; Berryman, J. G.; Bertete-Aguirre, H.; Bonner, B. P.; Roberts, J. J. & Wildenschild, D.
Object Type: Report
System: The UNT Digital Library
Hydrodynamic instability modeling for ICF (open access)

Hydrodynamic instability modeling for ICF

The intent of this paper is to review how instability growth is modeled in ICF targets, and to identify the principal issues. Most of the material has been published previously, but is not familiar to a wide audience. Hydrodynamic instabilities are a key issue in ICF. Along with laser-plasma instabilities, they determine the regime in which ignition is possible. At higher laser energies, the same issues determine the achievable gain. Quantitative predictions are therefore of the utmost importance to planning the ICF program, as well as to understanding current Nova results. The key fact that underlies all this work is the stabilization of short wavelengths.
Date: March 31, 1993
Creator: Haan, S. W.
Object Type: Article
System: The UNT Digital Library
Line intensities for diagnosing laser-produced plasmas (open access)

Line intensities for diagnosing laser-produced plasmas

We have measured relative line intensities of the K x-ray spectra of Si, Cl, and Ca from laser-produced plasmas to assess their usefulness as a plasma diagnostic. The different elements are added at low concentrations to CH disks which are irradiated at 5 x 10/sup 14/ W/cm/sup 2/ with a 0.53 ..mu..m laser pulse of 20 Joules at 1 nsec. The concentration of each element is kept low in order not to change the Z of the plasma, and therefore the plasma dynamics. The various spectra are measured with a time-resolved spectrograph to obtain line intensities as a function of time over the length of the laser pulse. These relative intensities of various He-like and H-like lines are compared with calculations from a steady-state level population code. The results give good consistency among the various line ratios. Agreement is not as good for analysis of the Li-like satellite lines. Modelling of the Li-like lines need further investigation. 10 references, 9 figures.
Date: October 31, 1983
Creator: Kauffman, R.L.; Matthews, D.L.; Lee, R.W.; Whitten, B.L. & Kilkenny, J.D.
Object Type: Article
System: The UNT Digital Library
Performance and measurements of the AGS and Booster beams (open access)

Performance and measurements of the AGS and Booster beams

Analyses of Hot Gas Stream Cleanup (HGSC) ashes and descriptions of filter performance were made to address the problems with filter operation that are apparently linked to the collected ash. This task is designed to generate data base of the key properties of ashes collected from operating advanced particle filters and to relate these ash properties to the operation and performance of these filters. Activities including initial formatting of the data base and entry, modification of the permeability model, and initial design of a high-temperature test device for measuring uncompacted bulk porosity of ash aggregates (indicator of relative cohesivity of the ash, filter cake porosity/permeability). Chemical analyses of hopper and filter cake ashes from Tidd showed that the consolidation degree could not be accounted for by condensation/adsorption from the flue gas; the mechanism is likely physical rearrangement of the ash particles.
Date: December 31, 1995
Creator: Weng, W. T.
Object Type: Article
System: The UNT Digital Library
Ultrasonic Assembly of Thermoplastic Parts (open access)

Ultrasonic Assembly of Thermoplastic Parts

Four ultrasonic methods were evaluated for assembly of experimental plastic parts for detonators: (1) welding, (2) crimping and staking, (3) insertion, and (4) reactivation of adhesives. For welding, staking and insertion, plastics with low elastic moduli, such as acrylics and polycarbonate, produced the best results. Thermosetting, hot-melt, and solution adhesives could all be activated ultrasonically to form good bonds on plastics and other materials. This evaluation indicated that thermoplastic detonator parts could be assembled ultrasonically in shorter times than by present production techniques with high bond strengths and high product acceptance rates.
Date: March 31, 1970
Creator: Schurman, W. R.
Object Type: Report
System: The UNT Digital Library
List of Nurserymen, Florists, and Dealer Licensed to Do Business in Texas and the Texas Orchard and Nursey Inspection Laws With Rules and Regulations (open access)

List of Nurserymen, Florists, and Dealer Licensed to Do Business in Texas and the Texas Orchard and Nursey Inspection Laws With Rules and Regulations

This report discusses the importance of the Texas Orchard and Nursery Inspection Law.
Date: 1931-03-31/1931-04-30
Creator: Del Curto, J. M. & McDonald, J. E.
Object Type: Book
System: The Portal to Texas History
Cost-effective applications of photovoltaics for electric utilities: An overview (open access)

Cost-effective applications of photovoltaics for electric utilities: An overview

Cost targets for the large-scale entry of photovoltaic (PV) systems keep moving, subject to the vagaries of global oil prices and the economic health of the world. Over the last four decades since a practical PV device was announced, costs have come down by a factor of 20 or more and this downward trend is expected to continue, albeit at a slower pace. Simultaneously, conversion efficiencies have nearly tripled. There are many applications today for which PV is cost-effective. In recognition of this, utility interest in PV is increasing and this is manifested by projects such as PVUSA and Central and South West`s renewable resource development effort. While no major technical barriers for the entry of PV systems have been uncovered, several key issues such as power quality, system reliability, ramp rates, spinning reserve requirements, and misoperation of protection schemes will have to be dealt with as the penetration of this technology increases. PV is still in the evolutionary phase and is expected to grow for several decades to come. Fueled by environmental considerations, interest in PV is showing a healthy rise both in the minds of the public and in the planning realms of the electric power community. In …
Date: December 31, 1993
Creator: Bigger, J. E.
Object Type: Article
System: The UNT Digital Library
Photovoltaics as a worldwide energy source (open access)

Photovoltaics as a worldwide energy source

Photovoltaic energy systems have historically been treated as a bulk power generation source for the future. However, utilities and other agencies involved with electrification throughout the world are beginning to find photovoltaics a least-cost option to meet specific loads both for themselves and their customers, in both off-grid and grid-connected applications. These expanding markets offer the potential of hundreds of megawatts of sales in the coming decade, but a strategy addressing both industrial growth and user acceptance is necessary to capitalize on this opportunity. 11 refs.
Date: December 31, 1991
Creator: Jones, G. J.
Object Type: Article
System: The UNT Digital Library
Analyses of containment structures with corrosion damage (open access)

Analyses of containment structures with corrosion damage

Corrosion damage to a nuclear power plant containment structure can degrade the pressure capacity of the vessel. For the low-carbon, low- strength steels used in containments, the effect of corrosion on material properties is discussed. Strain-to-failure tests, in uniaxial tension, have been performed on corroded material samples. Results were used to select strain-based failure criteria for corroded steel. Using the ABAQUS finite element analysis code, the capacity of a typical PWR Ice Condenser containment with corrosion damage has been studied. Multiple analyses were performed with the locations of the corrosion the containment, and the amount of corrosion varied in each analysis.
Date: December 31, 1996
Creator: Cherry, J.L.
Object Type: Article
System: The UNT Digital Library
FY 2002 Integrated Monitoring Plan for the Hanford Groundwater Monitoring Project (open access)

FY 2002 Integrated Monitoring Plan for the Hanford Groundwater Monitoring Project

This document is an integrated monitoring plan for the groundwater project and contains: well and constituent lists for monitoring required by the Atomic Energy Act of 1954 and its implementing orders ("surveillance monitoring"); other, established monitoring plans by reference; and a master well/ constituent/frequency matrix for the entire Hanford Site.
Date: October 31, 2001
Creator: Hartman, Mary J.; Dresel, P Evan; Lindberg, Jonathan W.; Newcomer, Darrell R. & Thornton, Edward C.
Object Type: Report
System: The UNT Digital Library
FY 2002 Integrated Monitoring Plan for the Hanford Groundwater Monitoring Project (open access)

FY 2002 Integrated Monitoring Plan for the Hanford Groundwater Monitoring Project

This document is an integrated monitoring plan for the groundwater project and contains: well and constituent lists for monitoring required by the Atomic Energy Act of 1954 and its implementing orders (''surveillance monitoring''); other, established monitoring plans by reference; and a master well/ constituent/frequency matrix for the entire Hanford Site.
Date: October 31, 2001
Creator: Hartman, Mary J; Dresel, P Evan; Lindberg, Jon W; Newcomer, Darrell R & Thornton, Edward C
Object Type: Report
System: The UNT Digital Library
Uncertainty analysis for low-level radioactive waste disposal performance assessment at Oak Ridge National Laboratory (open access)

Uncertainty analysis for low-level radioactive waste disposal performance assessment at Oak Ridge National Laboratory

A performance assessment of the operating Solid Waste Storage Area 6 (SWSA 6) facility for the disposal of low-level radioactive waste at the Oak Ridge National Laboratory has been prepared to provide the technical basis for demonstrating compliance with the performance objectives of DOE Order 5820.2A, Chapter 111.2 An analysis of the uncertainty incorporated into the assessment was performed which addressed the quantitative uncertainty in the data used by the models, the subjective uncertainty associated with the models used for assessing performance of the disposal facility and site, and the uncertainty in the models used for estimating dose and human exposure. The results of the uncertainty analysis were used to interpret results and to formulate conclusions about the performance assessment. This paper discusses the approach taken in analyzing the uncertainty in the performance assessment and the role of uncertainty in performance assessment.
Date: December 31, 1994
Creator: Lee, D. W.; Yambert, M. W. & Kocher, D. C.
Object Type: Article
System: The UNT Digital Library
Radiation Monitoring Unit, Radiological Sciences Department monthly report, January 1955 (open access)

Radiation Monitoring Unit, Radiological Sciences Department monthly report, January 1955

This report presents results on radiation monitoring from the radiological sciences department for January, 1955. Information is presented concerning radioactive effluent releases, personnel skin contamination, air sampling, and general radiation monitoring from the facilities.
Date: December 31, 1955
Creator: Stevens, A. J.
Object Type: Report
System: The UNT Digital Library
A Compton scatter camera for spectral imaging of 0.5 to 3.0 MeV gamma rays (open access)

A Compton scatter camera for spectral imaging of 0.5 to 3.0 MeV gamma rays

A prototype Compton scatter camera for imaging gamma rays has been built and tested. This camera addresses unique aspects of gamma-ray imaging at nuclear industrial sites, including gamma-ray energies in the 0.5 to 3.0 MeV range and polychromatic fields. Analytic models of camera efficiency, resolution and contaminating events are developed. The response of the camera bears strong similarity to emission computed tomography devices used in nuclear medicine. A direct Fourier based algorithm is developed to reconstruct two-dimensional images of measured gamma-ray fields. Iterative ART and MLE algorithms are also investigated. The point response of the camera to gamma rays of energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms are also investigated. The point response of the camera to gamma rays energies from 0.5 to 2.8 MeV is measured and compared to the analytic models. The direct reconstruction algorithm is at least ten times more efficient than the iterative algorithms and produces images that are, in general, of the same quality. Measured images of several phantoms are shown. Important results include angular resolutions as low as 4.4{degrees}, reproduction of phantom …
Date: December 31, 1994
Creator: Martin, J.B.
Object Type: Thesis or Dissertation
System: The UNT Digital Library