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Meteorological database for the United States (open access)

Meteorological database for the United States

A meteorological database has been developed to aid in the prediction of indoor radon concentrations in the United States. The database contains predicted typical monthly meteorological statistics at the county level derived from hourly meteorological data from 208 (234 for precipitation) geographically distinct monitoring stations. Interpolation and extrapolation techniques were used to predict statistics for counties not containing a meteorological monitoring site. The LBNL database includes statistics for meteorological variables including dry-bulb temperature, dew-point temperature, barometric pressure, wind speed, wind direction, hours of precipitation, precipitation, and derived infiltration degree-days. The database consists of individual files of derived statistics for each weather variable and is potentially useful for indoor radon modeling as well as for other purposes. Each file contains data values for all 12 months and an aggregation of the 12 months up to a yearly statistic for all county centroids. A test was conducted to assess the quality of interpolated values. Examples showing the use of the database for mapping infiltration degree-days and an application of the database to a statistical correlation analysis attempting to find meteorological factors influencing indoor radon levels in the United States is discussed.
Date: April 1, 1996
Creator: Apte, M.G.; Nero, A.V. & Revzan, K.L.
System: The UNT Digital Library
PUREX transition project case study (open access)

PUREX transition project case study

In December 1992, the US Department of Energy (DOE) directed that the Plutonium-Uranium Extraction (PUREX) Plant be shut down and deactivated because it was no longer needed to support the nation`s production of weapons-grade plutonium. The PUREX/UO{sub 2} Deactivation Project will establish a safe and environmentally secure configuration for the facility and preserve that configuration for 10 years. The 10-year span is used to predict future maintenance requirements and represents the estimated time needed to define, authorize, and initiate the follow-on decontamination and decommissioning activities. Accomplishing the deactivation project involves many activities. Removing major hazards, such as excess chemicals, spent fuel, and residual plutonium are major goals of the project. The scope of the PUREX Transition Project is described within.
Date: April 15, 1996
Creator: Jasen, W. G.
System: The UNT Digital Library
The Annenberg Foundation A National Arts Education Consortium Getty Center for Education In The Arts (open access)

The Annenberg Foundation A National Arts Education Consortium Getty Center for Education In The Arts

Press information, on the Annenberg Foundation, announcing their latest series of grants towards arts education. A $4.3 million challenge grant to six regional institutes to show how the arts can boost student academic achievements. The foundation is working with the Getty Center for Education and their consortia which includes, North Texas Institute for Educators on the Visual Arts.
Date: April 15, 1996
Creator: unknown
System: The UNT Digital Library
Annenberg Foundation awards $1.43 million school reform grant to UNT arts consortium (open access)

Annenberg Foundation awards $1.43 million school reform grant to UNT arts consortium

A news release report, on North Texas Institute for Educators on the Visual Arts, one of the six recipients nationally of a $4.3 million challenge grant announced by the Annenberg Foundation. The grant goal is to reform public schools using a bold program of arts education. The grant will provide $1.43 million for UNT"s North Texas Institute for Educators on the Visual Arts to demonstrate how education in the arts can improve students.
Date: April 15, 1996
Creator: LeMay, Nancy
System: The UNT Digital Library
Preliminary assessment of the effects of biaxial loading on reactor pressure vessel structural-integrity-assessment technology (open access)

Preliminary assessment of the effects of biaxial loading on reactor pressure vessel structural-integrity-assessment technology

Effects of biaxial loading on shallow-flaw fracture toughness were studied to determine potential impact on structural integrity assessment of a reactor pressure vessel (RPV) under pressurized thermal shock (PTS) transient loading and pressure-temperature (PT) loading produced by reactor heatup and cooldown transients. Biaxial shallow-flaw fracture-toughness tests results were also used to determine the parameter controlling fracture in the transition temperature range, and to develop a related dual-parameter fracture-toughness correlation. Shallow-flaw and biaxial loading effects were found to reduce the conditional probability of crack initiation by a factor of nine when the shallow-flaw fracture-toughness K{sub Jc} data set, with biaxial-loading effects adjustments, was substituted in place of ASME Code K{sub Ic} data set in PTS analyses. Biaxial loading was found to reduce the shallow-flaw fracture toughness of RPV steel such that the lower-bound curve was located between ASME K{sub Ic} and K{sub IR} curves. This is relevant to future development of P-T curve analysis procedures. Fracture in shallow-flaw biaxial samples tested in the lower transition temperature range was shown to be strain controlled. A strain-based dual-parameter fracture-toughness correlation was developed and shown to be capable of predicting the effect of crack-tip constraint on fracture toughness for strain-controlled fracture.
Date: April 1, 1996
Creator: Pennell, W. E.; Bass, B. R.; Bryson, J. W.; Dickson, T. L.; McAfee, W. J. & Merkle, J. G.
System: The UNT Digital Library
Simple model of the anisotropic penetration depth in high T{sub c} superconductors (open access)

Simple model of the anisotropic penetration depth in high T{sub c} superconductors

We present a simple model of some high {Tc} cuprates based upon superconducting (S) and normal (N) layers, which quantitatively fits the data of Bonn et al. for the low-temperature T dependence of the penetration depths {lambda}{sub a,b,c} in untwinned YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}, assuming s-wave intralyer pairing. This SN model also leads to anisotropic surface states, which complicate analysis of photoemission and tunneling measurements.
Date: April 1, 1996
Creator: Klemm, Richard A. & Liu, Samuel H.
System: The UNT Digital Library
Evaluation of multi-phase heat transfer and droplet evaporation in petroleum cracking flows (open access)

Evaluation of multi-phase heat transfer and droplet evaporation in petroleum cracking flows

A computer code ICRKFLO was used to simulate the multiphase reacting flow of fluidized catalytic cracking (FCC) riser reactors. The simulation provided a fundamental understanding of the hydrodynamics and heat transfer processes in an FCC riser reactor, critical to the development of a new high performance unit. The code was able to make predictions that are in good agreement with available pilot-scale test data. Computational results indicate that the heat transfer and droplet evaporation processes have a significant impact on the performance of a pilot-scale FCC unit. The impact could become even greater on scale-up units.
Date: April 1, 1996
Creator: Chang, S.L.; Lottes, S.A.; Petrick, M. & Zhou, C.Q.
System: The UNT Digital Library
Proceeding of the exotic nuclei symposium (open access)

Proceeding of the exotic nuclei symposium

This report contains viewgraphs of papers from the proceedings of the Erotic Nuclei Symposium.
Date: April 1, 1996
Creator: Moltz, D
System: The UNT Digital Library
Solid/liquid lubrication of ceramics at elevated temperatures (open access)

Solid/liquid lubrication of ceramics at elevated temperatures

This study investigates the effect of solid and liquid lubrication on friction and wear performance of silicon nitride (Si{sub 3}N{sub 4}) and cast iron. The solid lubricant was a thin silver film ({approx}2 {mu}m thick) produced on Si{sub 3}N{sub 4} by ion-beam-assisted deposition. A high-temperature polyol-ester-base synthetic oil served as the liquid lubricant. Friction and wear tests were performed with pin-on-disk and oscillating-slider wear test machines at temperatures up to 300{degrees}C. Without the silver films, the friction coefficients of Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4} test pairs were 0.05 to 0.14, and the average wear rates of Si{sub 3}N{sub 4} pins were {approx}5 x 10{sup -8} mm{sup 3} N{sup -1}. The friction coefficients of Si{sub 3}N{sub 4}/cast iron test pairs ranged from 0.08 to 0.11, depending on test temperature. The average specific wear rates of cast iron pins were {approx}3 x 10{sup -7} mm{sup 3} N{sup -1} m{sup -1}. However, simultaneous use of the solid-lubricant silver and synthetic oil on the sliding surfaces reduced friction coefficients to 0.02 to 0.08. Moreover, the wear of Si{sub 3}N{sub 4} pins and silver-coated Si{sub 3}N{sub 4} disks was so low that it was difficult to assess by a surface profilometer. The wear rates of …
Date: April 1, 1996
Creator: Erdemir, A.; Erck, R.A.; Fenske, G.R. & Hong, H.
System: The UNT Digital Library
A low power, tight seal, polyimide electrostatic microvalve (open access)

A low power, tight seal, polyimide electrostatic microvalve

An electrostatically-actuated polyimide microvalve is developed with sub-micron gaps between the electrodes to provide high force with low power consumption (< 1 mW). Built-in residual stress results in a curled bimorph cantilever which allows for a n-Licroactuator with large displacement. This microactuator is used to open and close a fluid path hole etched in silicon for a microvalve. The microactuator can be actuated with 25V for a displacement of 200 {mu}m. The cantilever actuator is mainly composed of polyimide, which is flexible enough to conform over the flow hole, thereby eliminating the need for the design of a valve seat.
Date: April 17, 1996
Creator: Lee, A.P.; Hamilton, J. & Trevino, J.
System: The UNT Digital Library
The contribution of carbonaceous aerosols to climate change (open access)

The contribution of carbonaceous aerosols to climate change

Contribution of aerosols to climate change results from two effects: clear-sky and cloudy-sky forcing. The clear-sky climate forcing by carbonaceous aerosols from biomass burning and fossil fuel burning depends on the relative contribution of scattering and absorption by the aerosols which in turn depends on the fraction of aerosol mass associated with black carbon and its size distribution. This paper reviews estimates for the emission of carbonaceous aerosols, placing these estimates in the context of estimates for the emissions of anthropogenic and natural sulfate aerosols and natural sources of organic particulate matter. The cloudy-sky forcing from carbonaceous aerosols is difficult to estimate because, among other factors, it depends on the amount of absorption by the aerosols in the cloud. It is also highly sensitive to the assumed pre-existing, natural aerosol abundance. An upper limit for this cloudy-sky forcing is -4.4 W/m{sup 2}, but may range as low as -2.4 W/m{sup 2}, depending on background aerosol concentrations. These estimates do not yet account for absorption of radiation by black carbon associated with cloud or the presence of pre-existing dust particles.
Date: April 1, 1996
Creator: Penner, J. E.; Chuang, C. C. & Liousse, C.
System: The UNT Digital Library
Use of WIMS-E lattice code for prediction of the transuranic source term for spent fuel dose estimation (open access)

Use of WIMS-E lattice code for prediction of the transuranic source term for spent fuel dose estimation

A recent source term analysis has shown a discrepancy between ORIGEN2 transuranic isotopic production estimates and those produced with the WIMS-E lattice physics code. Excellent agreement between relevant experimental measurements and WIMS-E was shown, thus exposing an error in the cross section library used by ORIGEN2.
Date: April 15, 1996
Creator: Schwinkendorf, K.N.
System: The UNT Digital Library
Crystalline structure in the confined-deconfined mixed phase: Neutron stars as an example (open access)

Crystalline structure in the confined-deconfined mixed phase: Neutron stars as an example

We review the differences in first order phase transition of single and multi-component systems, and then discuss the crystalline structure expected to exist in the mixed confined deconfined phase of hadronic matter. The particular context of neutron stars is chosen for illustration. The qualitative results are general and apply for example to the vapor-liquid transition in subsaturated asymmetric nuclear matter.
Date: April 18, 1996
Creator: Glendenning, N.K.
System: The UNT Digital Library
Multiple mechanisms of thermally activated plastic flow in shocked and unshocked tantalum. Revision 1 (open access)

Multiple mechanisms of thermally activated plastic flow in shocked and unshocked tantalum. Revision 1

We argue that the principal features of the plastic flow behavior of Ta can be described a model that incorporates a two-component Peierls-type mechanism and an ``obstacle`` mechanism in series. We compare results of calculations based on such a model with flow data for unalloyed Ta before and after shock loading to 45 GPa for 1.8 {mu}s. Our data suggest that the shock loading changes only structural parameters.
Date: April 22, 1996
Creator: Gourdin, W.H. & Lassila, D.H.
System: The UNT Digital Library
Modification of cathodic arc deposition profiles by magnetic multicusps (open access)

Modification of cathodic arc deposition profiles by magnetic multicusps

The deposition profile of a cathodic arc plasma source with and without magnetic macroparticle filter has been measured using a deposition probe technique. It has been found that the profile is close to a Gaussian and that the width of the profile depends on the cathode material. It was found that the dependence on the cathode material leads to a considerable radial variation of the elemental composition of the film when an alloy cathode is used. A magnetic multicusp field (magnetic bucket) near the exit of the plasma source or the magnetic filter was applied to flatten and homogenize the deposition profile.
Date: April 1, 1996
Creator: Anders, S.; MacGill, R. A.; Raoux, S. & Brown, I. G.
System: The UNT Digital Library
Estimating D and D costs for structures at DOE facilities: Some considerations (open access)

Estimating D and D costs for structures at DOE facilities: Some considerations

A number of issues are examined related to estimating decontamination and decommissioning costs for structures at US Department of Energy facilities. The ability to develop detailed estimates for such facilities is generally well established and the general range of costs for such activity is well understood. However, current ability to quickly develop credible planning estimates is more limited. A need exists for a continuing synthesis of experience to allow for an improved ability to develop both detailed and planning estimates.
Date: April 1, 1996
Creator: Davis, M.J.; Folga, S.; Swanston, R. & Janke, R.J.
System: The UNT Digital Library
Structural stability of LiMn{sub 2}O{sub 4} electrodes for lithium batteries (open access)

Structural stability of LiMn{sub 2}O{sub 4} electrodes for lithium batteries

the structural stability of LiMn{sub 2}O{sub 4}, which is of interest as an insertion electrode for rechargeable lithium batteries, is discussed with respect to processing techniques, composition, the Li- Mn-O phase diagram, and electrochemical behavior. Particular attention is paid to processing conditions that result in the formation of lithium-magnesium-oxide spinel products in which Mn{sup 2+} ions partially occupy the tetrahedral sites of the spinel structure. The electrochemical behavior of electron beam and rf magnetron sputtered thin film electrodes suggests the existence of partially inverse Li{sub 1-x}Mn{sub 2} O{sub 4} spinel structures during an initial charge to 5.3 volts.
Date: April 1, 1996
Creator: Thackeray, M.M.; Mansuetto, M.F. & Bates, J.B.
System: The UNT Digital Library
CP violation and flavor-changing-currents at {mu}{sup +}{mu}{sup minus} colliders (open access)

CP violation and flavor-changing-currents at {mu}{sup +}{mu}{sup minus} colliders

Production and decay (CP) asymmetries at {mu}{sup +}{mu}{sup {minus}} collider, in extensions of the Standard Model (SM) are reported. Production asymmetries appear to be very promising for a large range of parameters, decays are less effective. Importance of flavor- changing scalar currents involving the top are emphasized. At lepton colliders, the top-anticharm final state is uniquely suited for such searches. At a muon collider there is the novel possibility of tree level {mu}{sup +}{mu}{sup {minus}} {r_arrow} t{ovr c}. This talk is based on works done in collaboration with David Atwood and Laura Reina. 10 refs., 8 figs.
Date: April 2, 1996
Creator: Soni, A.
System: The UNT Digital Library
Synthetic strong ground motions for engineering design utilizing empirical Green`s functions (open access)

Synthetic strong ground motions for engineering design utilizing empirical Green`s functions

We present a methodology for developing realistic synthetic strong ground motions for specific sites from specific earthquakes. We analyzed the possible ground motion resulting from a M = 7.25 earthquake that ruptures 82 km of the Hayward fault for a site 1.4 km from the fault in the eastern San Francisco Bay area. We developed a suite of 100 rupture scenarios for the Hayward fault earthquake and computed the corresponding strong ground motion time histories. We synthesized strong ground motion with physics-based solutions of earthquake rupture and applied physical bounds on rupture parameters. By having a suite of rupture scenarios of hazardous earthquakes for a fixed magnitude and identifying the hazard to the site from the statistical distribution of engineering parameters, we introduce a probabilistic component into the deterministic hazard calculation. Engineering parameters of synthesized ground motions agree with those recorded from the 1995 Kobe, Japan and the 1992 Landers, California earthquakes at similar distances and site geologies.
Date: April 11, 1996
Creator: Hutchings, L. J.; Jarpe, S. P.; Kasameyer, P. W. & Foxall, W.
System: The UNT Digital Library
Monte Carlo modeling of neutron and gamma-ray imaging systems (open access)

Monte Carlo modeling of neutron and gamma-ray imaging systems

Detailed numerical prototypes are essential to design of efficient and cost-effective neutron and gamma-ray imaging systems. We have exploited the unique capabilities of an LLNL-developed radiation transport code (COG) to develop code modules capable of simulating the performance of neutron and gamma-ray imaging systems over a wide range of source energies. COG allows us to simulate complex, energy-, angle-, and time-dependent radiation sources, model 3-dimensional system geometries with ``real world`` complexity, specify detailed elemental and isotopic distributions and predict the responses of various types of imaging detectors with full Monte Carlo accuray. COG references detailed, evaluated nuclear interaction databases allowingusers to account for multiple scattering, energy straggling, and secondary particle production phenomena which may significantly effect the performance of an imaging system by may be difficult or even impossible to estimate using simple analytical models. This work presents examples illustrating the use of these routines in the analysis of industrial radiographic systems for thick target inspection, nonintrusive luggage and cargoscanning systems, and international treaty verification.
Date: April 1, 1996
Creator: Hall, J.
System: The UNT Digital Library
Magnetic inelastic scattering: Present results and future trends (open access)

Magnetic inelastic scattering: Present results and future trends

Experience over the last 15 years has shsown that pulsed neutron spectrometers are able to contribute to the field of magnetic inelastic scattering. Such spectrometers have high resolution and wide dynamic range, both of which are necessary in order to characterize the magnetic response of the complex systems of current interest, ranging from rare earth-transition metal permanent magnets to quantum critical scatterers. Howevera, all these studies have been constrained by current flux limitations. The development of more powerful spallation neutron sources, such as the JHP, is likely to transform these interesting demonstrations of the potential of pulsed neutron scattering into routine tools for the study of magnetic correlations.
Date: April 1996
Creator: Osborn, R.
System: The UNT Digital Library
Design, manufacture, and calibration of infrared radiometric blackbody sources (open access)

Design, manufacture, and calibration of infrared radiometric blackbody sources

A Radiometric Calibration Station (RCS) is being assembled at the Los Alamos National Laboratories (LANL) which will allow for calibration of sensors with detector arrays having spectral capability from about 0.4-15 {mu}m. The configuration of the LANL RCS. Two blackbody sources have been designed to cover the spectral range from about 3-15 {mu}m, operating at temperatures ranging from about 180-350 K within a vacuum environment. The sources are designed to present a uniform spectral radiance over a large area to the sensor unit under test. The thermal uniformity requirement of the blackbody cavities has been one of the key factors of the design, requiring less than 50 mK variation over the entire blackbody surface to attain effective emissivity values of about 0.999. Once the two units are built and verified to the level of about 100 mK at LANL, they will be sent to the National Institute of Standards and Technology (NIST), where at least a factor of two improvement will be calibrated into the blackbody control system. The physical size of these assemblies will require modifications of the existing NIST Low Background Infrared (LBIR) Facility. LANL has constructed a bolt-on addition to the LBIR facility that will allow calibration …
Date: April 1, 1996
Creator: Byrd, D. A.; Michaud, F. D. & Bender, S. C.
System: The UNT Digital Library
The FALSTF last-flight computer program (open access)

The FALSTF last-flight computer program

FALSTF is a computer program used with the DORT transport code to calculate fluxes and doses at detector points located outside the DORT geometry model. An integral form of the transport equation is solved to obtain the flux at the detector points resulting from the uncollided transport of the emergent particle density within the geometry as calculated by DORT. Both R-Z and R-{theta} geometries are supported.
Date: April 1, 1996
Creator: Childs, R. L.
System: The UNT Digital Library
Structure functions of electroweak boson and leptons (open access)

Structure functions of electroweak boson and leptons

The QCD structure of the electroweak bosons is reviewed and the lepton structure function is defined and calculated. The leading order splitting functions of electron into quarks are extracted, showing an important contribution from {gamma}-Z interference. Leading logarithmic QCD evolution equations are constructed and solved in the asymptotic region where log{sup 2} behavior of the Parton densities is observed. Possible applications with clear manifestation of ``resolved`` photon and weak bosons are discussed. 8 refs., 3 figs.
Date: April 2, 1996
Creator: Slominski, W & Szwed, J.
System: The UNT Digital Library