Simultaneous evaluation of interrelated cross sections by generalized least-squares and related data file requirements (open access)

Simultaneous evaluation of interrelated cross sections by generalized least-squares and related data file requirements

Though several cross sections have been designated as standards, they are not basic units and are interrelated by ratio measurements. Moreover, as such interactions as /sup 6/Li + n and /sup 10/B + n involve only two and three cross sections respectively, total cross section data become useful for the evaluation process. The problem can be resolved by a simultaneous evaluation of the available absolute and shape data for cross sections, ratios, sums, and average cross sections by generalized least-squares. A data file is required for such evaluation which contains the originally measured quantities and their uncertainty components. Establishing such a file is a substantial task because data were frequently reported as absolute cross sections where ratios were measured without sufficient information on which reference cross section and which normalization were utilized. Reporting of uncertainties is often missing or incomplete. The requirements for data reporting will be discussed.
Date: October 25, 1984
Creator: Poenitz, W.P.
System: The UNT Digital Library
Nondestructive assay instrumentation for a Savannah River Plant upgrade project (open access)

Nondestructive assay instrumentation for a Savannah River Plant upgrade project

We have designed and are developing three different computer-based spectrometer systems. Two will measure the concentration of Pu solutions by gamma-ray and by stimulated x-ray fluorescence emissions of solid samples in closed containers. All systems are coupled to remote terminals and bar code readers, and also to mini-computer based multichannel analyzers, which in turn are linked to another computer to provide a state-of-the-art nondestructive assay capability. Installation at the Savannah River Plant is planned in late 1985. 7 references.
Date: October 25, 1984
Creator: Camp, D.; Eckels, D.; Gunnink, R.; Prindle, A. & Ruhter, W.
System: The UNT Digital Library
Comparison of observed and predicted Kr-85 air concentrations (open access)

Comparison of observed and predicted Kr-85 air concentrations

A computer code, ANEMOS has been written to estimate concentrations in air and ground deposition rates for Atmospheric Nuclides Emitted from Multiple Operation Sources. This code uses a modified Gaussian plum equation. Output from ANEMOS includes annual-average air concentrations and ground deposition rates of dispersed radionuclides and daughters. To use the environmental transport model properly, some estimate of the models predictive accuracy must be obtained. To validate the ANEMOS model, one year of weekly average Kr-85 concentrations observed at 13 stations located 28 to 144 km distant from continuous point source at the Savannah River Plant (SRP), Aiken, South Carolina, have been used. There was a general tendency for the model to underpredict the observed air concentrations slightly. Pearsons's correlation between pairs of logarithms of observed and predicted annual-average values was r = 0.84. The monthly results tend to show more scatter than do either the seasonal or the annual comparisons. 18 references, 3 figures, 3 tables.
Date: April 25, 1984
Creator: Yildiran, M. & Miller, C. W.
System: The UNT Digital Library
AI/Simulation Fusion Project at Lawrence Livermore National Laboratory (open access)

AI/Simulation Fusion Project at Lawrence Livermore National Laboratory

This presentation first discusses the motivation for the AI Simulation Fusion project. After discussing very briefly what expert systems are in general, what object oriented languages are in general, and some observed features of typical combat simulations, it discusses why putting together artificial intelligence and combat simulation makes sense. We then talk about the first demonstration goal for this fusion project.
Date: April 25, 1984
Creator: Erickson, S.A.
System: The UNT Digital Library
Linear pinch driven by a moving compact torus (open access)

Linear pinch driven by a moving compact torus

In principle, a Z-pinch of sufficiently large aspect ratio can provide arbitrarily high magnetic field intensity for the confinement of plasma. In practice, however, achievable field intensities and timescales are limited by parasitic inductances, pulse driver power, current, voltage, and voltage standoff of nearby insulating surfaces or surrounding gas. Further, instabilities may dominate to prevent high fields (kink mode) or enhance them (sausage mode) but in a nonuniform and uncontrollable way. In this paper we discuss an approach to producing a high-field-intensity pinch using a moving compact torus. The moving torus can serve as a very high power driver and may be used to compress a pre-established pinch field, switch on an accelerating pinch field, or may itself be reconfigured to form an intense pinch. In any case, the high energy, high energy density, and high velocity possible with an accelerated compact torus can provide extremely high power to overcome, by a number of orders of magnitude, the limitations to pinch formation described earlier. In this paper we will consider in detail pinches formed by reconfiguration of the compact torus.
Date: April 25, 1984
Creator: Hartman, C. W.; Hammer, J. H. & Eddleman, J. L.
System: The UNT Digital Library
Ovine model for studying pulmonary immune responses (open access)

Ovine model for studying pulmonary immune responses

Anatomical features of the sheep lung make it an excellent model for studying pulmonary immunity. Four specific lung segments were identified which drain exclusively to three separate lymph nodes. One of these segments, the dorsal basal segment of the right lung, is drained by the caudal mediastinal lymph node (CMLN). Cannulation of the efferent lymph duct of the CMLN along with highly localized intrabronchial instillation of antigen provides a functional unit with which to study factors involved in development of pulmonary immune responses. Following intrabronchial immunization there was an increased output of lymphoblasts and specific antibody-forming cells in efferent CMLN lymph. Continuous divergence of efferent lymph eliminated the serum antibody response but did not totally eliminate the appearance of specific antibody in fluid obtained by bronchoalveolar lavage. In these studies localized immunization of the right cranial lobe served as a control. Efferent lymphoblasts produced in response to intrabronchial antigen were labeled with /sup 125/I-iododeoxyuridine and their migrational patterns and tissue distribution compared to lymphoblasts obtained from the thoracic duct. The results indicated that pulmonary immunoblasts tend to relocate in lung tissue and reappear with a higher specific activity in pulmonary lymph than in thoracic duct lymph. The reverse was observed …
Date: November 25, 1984
Creator: Joel, D. D. & Chanana, A. D.
System: The UNT Digital Library
Enhancing the performance of a high-gain free electron laser operating at millimeter wavelengths (open access)

Enhancing the performance of a high-gain free electron laser operating at millimeter wavelengths

A high-gain, high extraction efficiency, free electron laser (FEL) amplifier operating at the Experimental Test Accelerator (ETA) at 34.6 GHz has demonstrated a small signal gain of 13.4 dB/m. With a 30 kW input signal, the amplifier has produced a saturated output of 80 MW and a 5% extraction efficiency. Comparison of these results with a linear model at small signal levels indicates that the amplifier can deliver saturated output starting from noise, if the brightness of the electron beam is sufficiently high. The brightness of the ETA is far below that possible with optimized choice of practical design characteristics such as peak voltage, cathode type, gun electrode geometry, and focusing field topology. In particular, the measured brightness of the ETA injector is limited by plasma effects from the present cold, plasma cathode. As part of a coordinated theoretical and experimental effort to improve injector performance, we are using the EBQ gun design code to explore the current limits of gridless, relativistic, Pierce columns with moderate current density (>50 A/cm/sup 2/) at the cathode. The chief component in our experimental effort is a readily modified electron gun that will allow us to test many candidate cathode materials, types, and electrode …
Date: October 25, 1984
Creator: Barletta, W. A.; Anderson, B.; Fawley, W. M.; Neil, V. K.; Orzechowski, T. J.; Prosnitz, D. et al.
System: The UNT Digital Library
Overview of geochemical modeling needs for nuclear waste management (open access)

Overview of geochemical modeling needs for nuclear waste management

Research needs include, but are not limited to: measurement of basic thermodynamic data at elevated temperatures for species identified by modelers as potentially important; evaluation of substances which control or limit precipitation and/or nucleation kinetics; sorption studies specifically designed to provide data needed for modeling. This includes the rate of sorption, desorption, and the characterization of the solid and aqueous phases; site-mixing models and thermodynamic data for secondary minerals that form solid solutions; the development of standard techniques for measuring rate laws for precipitation and dissolution kinetics; and measurement of rate laws describing redox kinetics, dissolution, and precipitation involving aqueous species and solid phases of interest to geochemical modelers.
Date: May 25, 1984
Creator: Isherwood, D. & Wolery, T.
System: The UNT Digital Library
Uranium Density and Enrichment in Fuel Tubes Determined from 232U and 235U Y-Activities (open access)

Uranium Density and Enrichment in Fuel Tubes Determined from 232U and 235U Y-Activities

Gamma spectroscopy is used to determine 235U density and enrichment in U-Al fuel tubes containing recycled fuel. A collimated HPGe Y-detector views the tube surface, such that U-Al disk volumes of 6.35 mm diameter and approximately 1.0 mm thickness are examined. The Y-activities from 232U and 235U, along with the tube design parameters, are used to deduce the attenuation-corrected results. Respective density and enrichment variations of less than 1 percent and less than 0.6e percent were measurable with 2000 sec counting time per tube location. Such measurements are useful for certifying tube quality and characterizing problems associated with blending the U-Al alloy.
Date: May 25, 1984
Creator: Winn, Willard G.
System: The UNT Digital Library