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[RE: School Board Award Announcement: Kennedy Center / NSBA]

Description: Photocopy of a letter from Julie Abel, Program Associate, Getty Center for Education in the Arts, to RIG Directors. The letter is in regard to information on the Kennedy Center Alliance for Arts Education Network, KCAAEN, and National School Boards Association, NSBA, Award that recognizes school boards that have demonstrated outstanding commitment to high quality arts education. Attached to the letter is a copy of the 1996 Award Announcement.
Date: August 28, 1995
Creator: Abel, Julie
Partner: UNT Libraries Special Collections

Summary of beryllium specifications, current and historical

Description: This report summarizes beryllium properties included in producer, Department of Energy, and government specifications. The specifications are divided into two major categories: current and historical. Within each category the data are arranged primarily according to increasing purity and secondarily by increasing tensile properties. Qualitative comments on formability and weldability are included. Also, short summaries of powder production and consolidation techniques are provided.
Date: December 28, 1990
Creator: Abeln, S.P. & Kyed, P.
Partner: UNT Libraries Government Documents Department

The role of catalyst precursor anions in coal gasification. Third quarterly report

Description: The aims of the proposed project are to enrich our understanding of the roles of various aqueous soluble catalyst precursor anions on the surface electrical properties of coal and to ascertain the influence of the surface charge on the adsorption, dispersion, and activities of calcium and potassium. These goals will be achieved by impregnating a North Dakota lignite (PSOC 1482) and its demineralized derivative with calcium or potassium catalyst precursors containing acetate (CH{sub 3}COO{sup {minus}}), chloride (Cl{sup {minus}}), nitrate (NO{sub 3}{sup {minus}}), sulfate (SO{sub 4}{sup 2{minus}}), and carbonate (CO{sub 3}{sup 2{minus}}) anions. Catalyst loading will be conducted under well-controlled conditions of solution pH and ionic strength. In the last quarter, the surface charge properties of the coal was determined as a function of acetate (CH{sub 3}COO{sup {minus}}), chloride (Cl{sup {minus}}), nitrate (NO{sup 3}{sup {minus}}), carbonate (CO{sub 3}{sup 2{minus}}) or sulfate (SO{sub 4}{sup 2{minus}})concentration using the respective potassium salts of these anions. In general, low anion concentrations (10{sup {minus}3} or 10{sup {minus}2} mol/L) had little effect on the zeta potentials of the coals. However, the surface charge densities of the coal become less negative at 10-1 mol/L of the nitrate, carbonate or sulfate anions. These trends suggest that the surface charge density of the coal is controlled by the adsorption of potassium ions (K{sup +}) onto the coal particles. The net negative charge on the coal panicles creates a repulsive force between the anions and the coal surface and prevents the anions from exerting any significant effect on the coal`s electrokinetic properties.
Date: August 28, 1992
Creator: Abotsi, G. M. K.
Partner: UNT Libraries Government Documents Department

The role of catalyst precursor anions in coal gasification

Description: The aims of the proposed project are to enrich our understanding of the roles of various aqueous soluble catalyst precursor anions on the surface electrical properties of coal and to ascertain the influence of the surface charge on the adsorption, dispersion, and activities of calcium and potassium. These goals will be achieved by impregnating a North Dakota lignite (PSOC 1482) and its demineralized derivative with calcium or potassium catalyst precursors containing acetate (CH{sub 3}COO{sup {minus}}), chloride (Cl{sup {minus}}), nitrate (NO{sub 3}{sup {minus}}), sulfate (SO{sub 4}{sup 2{minus}}), and carbonate (CO{sub 3}{sup 2{minus}}) anions. Catalyst loading will be conducted under well-controlled conditions of solution pH and ionic strength. In the last quarter, the surface charge properties of the coal was determined as a function of acetate (CH{sub 3}COO{sup {minus}}), chloride (Cl{sup {minus}}), nitrate (NO{sup 3}{sup {minus}}), carbonate (CO{sub 3}{sup 2{minus}}) or sulfate (SO{sub 4}{sup 2{minus}})concentration using the respective potassium salts of these anions. In general, low anion concentrations (10{sup {minus}3} or 10{sup {minus}2} mol/L) had little effect on the zeta potentials of the coals. However, the surface charge densities of the coal become less negative at 10-1 mol/L of the nitrate, carbonate or sulfate anions. These trends suggest that the surface charge density of the coal is controlled by the adsorption of potassium ions (K{sup +}) onto the coal particles. The net negative charge on the coal panicles creates a repulsive force between the anions and the coal surface and prevents the anions from exerting any significant effect on the coal's electrokinetic properties.
Date: August 28, 1992
Creator: Abotsi, G.M.K.
Partner: UNT Libraries Government Documents Department

Focused Ion Beam Induced Effects on MOS Transistor Parameters

Description: We report on recent studies of the effects of 50 keV focused ion beam (FIB) exposure on MOS transistors. We demonstrate that the changes in value of transistor parameters (such as threshold voltage, V{sub t}) are essentially the same for exposure to a Ga+ ion beam at 30 and 50 keV under the same exposure conditions. We characterize the effects of FIB exposure on test transistors fabricated in both 0.5 {micro}m and 0.225 {micro}m technologies from two different vendors. We report on the effectiveness of overlying metal layers in screening MOS transistors from FIB-induced damage and examine the importance of ion dose rate and the physical dimensions of the exposed area.
Date: July 28, 1999
Creator: Abramo, Marsha T.; Antoniou, Nicholas; Campbell, Ann N.; Fleetwood, Daniel M.; Hembree, Charles E.; Jessing, Jeffrey R. et al.
Partner: UNT Libraries Government Documents Department

Development of a video-based slurry sensor for on-line ash analysis. Sixth quarterly technical progress report, January 1, 1996--March 31, 1996

Description: Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content. Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by PCS Phosphate for off-line analysis of dry flotation concentrate. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, calibration tests were conducted on-site at the Middle Fork coal preparation plant owned and operated by Pittston Coal Company. After several plant visits, a consistent sensor calibration was obtained with approximately 95% of all samples analyzed falling within {plus_minus}2% ash of the best fit calibration line. The resolution of the optical analyzer was found to be approximately 0.5% ash per gray level increment. A linear neural network learning algorithm was found to be the most appropriate method for calibrating the sensor. The sensor now appears to be ready for installation and long-term testing at the Middle Fork test site.
Date: April 28, 1996
Creator: Adel, G.T. & Luttrell, G.H.
Partner: UNT Libraries Government Documents Department

Nuclear excitation by electronic transition (NEET).

Description: We present a report on recent measurements using the Advanced Photon Source at Argonne National Laboratory to explore the phenomenon of Nuclear Excitation by Electronic Transition (NEET) in the {sup 189}Os atomic/nuclear system.
Date: April 28, 1999
Creator: Ahmad, I.; Dunford, R. W.; Esbensen, H.; Gemmell, D. S.; Kanter, E. P.; Kraessig, B. et al.
Partner: UNT Libraries Government Documents Department

Measurement of the {sup 44}Ti half-life and its significance for supernova.

Description: In 1998, we reported the three-laboratory measurement of the {sup 44}Ti half-life which was determined relative to the well known value (5.2714 {+-} 0.0005 yr) of the {sup 60}Co half-life. We have continued the measurement at Argonne and Jerusalem and inclusion of data points for additional two years does not change our published value of 59.0 {+-} 0.6 yr.
Date: August 28, 1999
Creator: Ahmad, I.; Greene, J. P.; Kutschera, W. & Paul, M.
Partner: UNT Libraries Government Documents Department

Subsurface Flow and Contaminant Transport Documentation and User's Guide

Description: This report documents a finite element code designed to model subsurface flow and contaminant transport, named FACT. FACT is a transient three-dimensional, finite element code designed to simulate isothermal groundwater flow, moisture movement, and solute transport in variably saturated and fully saturated subsurface porous media. The code is designed specifically to handle complex multi-layer and/or heterogeneous aquifer systems in an efficient manner and accommodates a wide range of boundary conditions. Additionally, 1-D and 2-D (in Cartesian coordinates) problems are handled in FACT by simply limiting the number of elements in a particular direction(s) to one. The governing equations in FACT are formulated only in Cartesian coordinates.
Date: July 28, 1999
Creator: Aleman, S.E.
Partner: UNT Libraries Government Documents Department

Plasma electrode pockels cell for the National Ignition Facility

Description: The National Ignition Facility (NIF), now under construction at Lawrence Livermore National Laboratory, will be the largest laser fusion facility ever built. The NIF laser architecture is based on a multi-pass power amplifier to reduce cost and maximize performance. A key component in this laser design is an optical switch that closes to trap the optical pulse in the cavity for four gain passes and then opens to divert the optical pulse out of the amplifier cavity. The switch is comprised of a Pockels cell and a polarizer and is unique because it handles a beam that is 40 cm x 40 cm square and allows close horizontal and vertical beam spacing. Conventional Pockels cells do not scale to such large apertures or the square shape required for close packing. Our switch is based on a Plasma-Electrode Pockels Cell (PEPC). In a PEPC, low-pressure helium discharges (1-2 kA) are formed on both sides of a thin slab of electro-optic material. Typically, we use KH{sub 2}PO{sub 4 } crystals (KDP). The discharges form highly conductive, transparent sheets that allow uniform application of a high-voltage pulse (17 kV) across the crystal. A 37 cm x 37 cm PEPC has been in routine operation for two years on the 6 k.J Beamlet laser at LLNL. For the NIF, a module four apertures high by one wide (4x1) is required. However, this 4x1 mechanical module will be comprised electrically of a pair of 2x1 sub-modules. Last year (FY 97), we demonstrated full operation of a prototype 2x1 PEPC. In this PEPC, the plasma spans two KDP crystals. A major advance in the 2x1 PEPC over the Beamlet PEPC is the use of anodized aluminum construction that still provides sufficient insulation to allow formation of the planar plasmas.
Date: July 28, 1998
Creator: Alger, T.; Biltoft, P.; Boley, C. D.; Fochs, S.; Funkhouser, B. & Rhodes, M. A.
Partner: UNT Libraries Government Documents Department

Using life-cycle analysis to estimate economic performance

Description: One of the principal tools of industrial ecology is life-cycle assessment which intends to improve overall economic efficiency and to minimize negative environmental impacts of products, processes, and facilities. This paper describes a general methodology for environmentally responsible assessment of these activities; it discusses some of the underlying considerations for this assessment which are accessible by rigorous quantitative analysis; and an overall economic performance metric is proposed which puts both environmental and economic considerations on a common basis. Finally, some considerations involved in this approach is introduced as a guide to environmentally sound design and management.
Date: March 28, 1996
Creator: Allenby, B.R.
Partner: UNT Libraries Government Documents Department

Modeling the absorption of intense, short laser pulses in steep density gradients

Description: A subroutine which calculates the absorption of short pulse electromagnetic radiation in a material has been installed into the laser fusion modeling program called LASNEX. Calculational results show the necessity for NLTE physics to account for ionization, the development of non-exponential density profiles for the expanding plasma and movement of the critical point toward the surface which results in Doppler shifts of the reflected light. Comparison of calculations of local scale lengths with experiments shows not only good agreement but the correct scaling with intensity. 8 refs., 5 figs.
Date: January 28, 1991
Creator: Alley, W.E.
Partner: UNT Libraries Government Documents Department

A Coherent FMCW LIDAR Mapping System for Automated Tissue Debridment

Description: The Oak Ridge National Laboratory (ORNL) is developing a prototype 850-nm FMCW lidar system for mapping tissue damage in burn cases for the US Army Medical Research and Material Command. The laser system will provide a 3D-image map of the burn and surrounding area and provide tissue damage assessment.
Date: June 28, 1999
Creator: Allgood, G.O.; Hutchinson, D.P. & Richards, R.K.
Partner: UNT Libraries Government Documents Department

Geological and petrophysical characterization of the Ferron Sandstone for 3-D simulation of a fluvial-deltaic reservoir. Technical progress report, April 1--June 30, 1995

Description: The objective of this project is to develop a comprehensive, interdisciplinary, and quantitative characterization of a fluvial-deltaic reservoir which will allow realistic inter-well and reservoir-scale modeling to be constructed for improved oil-field development in similar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah will be quantitatively determined. Both new and existing data will be integrated into a three-dimensional representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations. Technical progress this quarter is divided into regional stratigraphy, case studies, stochastic modeling and fluid-flow simulation, and technology transfer activities. The regional stratigraphy of the Ferron Sandstone outcrop belt from Last Chance Creek to Ferron Creek is being described and interpreted. Photomosaics and a database of existing surface and subsurface data are being used to determine the extent and depositional environment of each parasequence, and the nature of the contacts with adjacent rocks or flow units. For the second field season, detailed geological and petrophysical characterization of the primary reservoir lithofacies typically found in a fluvial-dominated deltaic reservoir, is continuing at selected case-study areas.
Date: July 28, 1995
Creator: Allison, M.L.
Partner: UNT Libraries Government Documents Department

Evaluation of Internal Criticality of the Plutonium Dispostion MOX SNF Waste Form

Description: The purpose of this calculation is to perform a parametric study to determine the effects of fission product leaching, assembly collapse, and iron oxide loss ({Delta}Fe{sub 2}O{sub 3}) on the reactivity of a waste package (WP) containing mixed oxide (MOX) spent nuclear fuel (SNF). Previous calculations (CRWMS M&O 1998a) have shown that the criticality control features of the WP are adequate to prevent criticality of a flooded WP for all the enrichment/burnup pairs expected for the MOX SNF. Therefore, the objective of this calculation is to determine the increase in reactivity that might result from possible degradation of the WP criticality control features. Specifically, this calculation tests the sensitivity of effective neutron multiplication factor (k{sub eff}) to loss (from the WP) of the following: (1) fission product neutron absorbers, or (2) moderator displacement material (principally, the iron oxide that results from the corrosion of carbon steel).
Date: September 28, 1999
Creator: Alsaed, A.A.
Partner: UNT Libraries Government Documents Department

Sanitary Landfill Supplemental Test Final Report

Description: This report summarizes the performance of the Sanitary Landfill Supplemental Test data, an evaluation of applicability, conclusions, recommendations, and related information for implementation of this remediation technology at the SRS Sanitary Landfill.
Date: July 28, 1999
Creator: Altman, D. J.
Partner: UNT Libraries Government Documents Department

Image Appraisal for 2D and 3D Electromagnetic Inversion

Description: Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and posterior model covariance matrices can be directly calculated. A method to examine how the horizontal and vertical resolution varies spatially within the electromagnetic property image is developed by examining the columns of the model resolution matrix. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how errors in the inversion process such as data noise and incorrect a priori assumptions about the imaged model map into parameter error. This type of image is shown to be useful in analyzing spatial variations in the image sensitivity to the data. A method is analyzed for statistically estimating the model covariance matrix when the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion). A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on 2D and 3D synthetic cross well EM data sets, as well as a field data set collected at the Lost Hills Oil Field in Central California.
Date: January 28, 1999
Creator: Alumbaugh, D.L. & Newman, G.A.
Partner: UNT Libraries Government Documents Department