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94,188 Matching Results

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(open access)

Diamond-turning tool setting by interferogram analysis

A method was developed to establish a numerically controlled tool path with respect to the work spindle centerline. Particularly adapted to the diamond turning of optics, this method is based upon interferogram analysis and is applicable to the establishment of the work spindle centerline relative to the tool path for any center-turned optic having a well-defined vertex radius of curvature. The application reported is for an f/2 concave spherical mirror.

Date: October 22, 1980

Creator: Rasnick, W.H. & Yoder, R.C.

Object Type: Report

System: The UNT Digital Library

(open access)

Addition of bromine as a diagnostic gas to inertial confinement fusion target microspheres

Currently, direct fuel rho r measurements on Inertial Confinement Fusion (ICF) targets by neutron activation of the argon tracer gas mixed with the DT fuel would require a 100 fold increase in neutron yield. Bromine, on the other hand, has excellent properties for neutron activation analysis at neutron yields of 10two' to 10/sup 8/, when present at an internal pressure of from 0.1 to 0.2 atmospheres. Bromine addition is accomplished in a 2 furnace system using the dried-gel method of microsphere production. An upper furnace operated at 1500/sup 0/C is separated from a lower furnace by a cooled zone. The lower furnace is filled with bromine gas and operated at approximately 1250/sup 0/C. The upper furnace is the glass production furnace. The cooled zone in between the upper and lower furnace is to prevent the hot bromine gas from rising into the upper furnace. The microspheres pass through the cooled zone and immediately into the 1250/sup 0/C bromine furnace where the bromine permeates into the spheres.

Date: August 22, 1980

Creator: Morrison, R. L.

Object Type: Article

System: The UNT Digital Library

(open access)

Arsenic Removal From Gaseous Streams

Uranium feed materials, depending on the production process, have been found to contain arsenic (As) as a contaminant. Analyses show the As to be present as As pentafluoride (AsF{sub 5}) and/or hexafluoroarsenic acid (HAsF{sub 6}) and enter the enrichment cycle through contaminated hydrogen fluoride (HF). Problems related to corrosion of cylinder valves and plugging of feed lines and valves have been attributed to the As. Techniques to separate AsF{sub 5} from uranium hexafluoride (UF{sub 6}) using sodium fluoride (NaF) as a trapping media were successful and will be discussed. Procedures to significantly reduce (up to 97%) the level of As in HF will also be reported. 5 figs., 9 tabs.

Date: November 22, 1989

Creator: Russell, R. G. & Otey, M. G.

Object Type: Report

System: The UNT Digital Library

(open access)

Interim Report on the Development of an Air Pulser for Pulse Column Application

The Idaho Chemical Processing Plant for several years has been studying various pulsing systems, used in extraction columns for processing irradiated nucIear fuel elements, in an effort to eliminate the mechanical difficuittes in present pulsing systems. An air puising system has been demonstrated, and a discussion is given of experimental work, pulser design, and plant operational experience with this system. It is concluded, from work completed thus far that air puising of extraction columns is a considerable improvement over other systems. (auth)

Date: September 22, 1961

Creator: Weech, M. E.; P'Pool, R. S. & MacQueen, D. K.

Object Type: Report

System: The UNT Digital Library

(open access)

Injection septum magnets for the Loma Linda medical accelerator

The injection beamline runs over the last magnet before a long straight section and is then displaced downward 55.88 cm to the accelerator beamline. The displacement is magnetic and the final deflection onto the synchrotron orbit is by an electric kicker. The first component, the reverse septum magnet, bends the injection beam 25)degree) downward. This is followed by the injection septum (20)degree) bend upward) and the final injection kicker (5)degree) bend upward). The septum magnets produce a peak field of 3.4 K gauss at a current of 28,000 amperes within a 0.1 msec long pulse. The electric kicker produces a field of 7.3 KV/cm with a pulse length of 0.0011 msec. The septum magnets are similar to each other in construction with a bending radium of 72.7 cm. The curvature is required to increase the effective aperture. Each magnet has a single-turn copper coil bonded to a stainless steel plate for reinforcement. This eliminates insulating material, which could be subject to radiation damage, at the septum. The stainless steel plate is welded to the magnet laminations. The current is confined to the septum by the insulation between the laminations, which are a standard core material. The total septum thickness with …

Date: September 22, 1987

Creator: Satti, J.A.

Object Type: Article

System: The UNT Digital Library

(open access)

Background field coils for the High Field Test Facility

The High Field Test Facility (HFTF), presently under construction at LLNL, is a set of superconducting coils that will be used to test 1-m-o.d. coils of prototype conductors for fusion magnets in fields up to 12 T. The facility consists of two concentric sets of coils; the outer set is a stack of Nb-Ti solenoids, and the inner set is a pair of solenoids made of cryogenically-stabilized, multifilamentary Nb/sub 3/Sn superconductor, developed for use in mirror-fusion magnets. The HFTF system is designed to be parted along the midplane to allow high-field conductors, under development for Tokamak fusion machines, to be inserted and tested. The background field coils were wound pancake-fashion, with cold-welded joints at both the inner and outer diameters. Turn-to-turn insulation was fabricated at LLNL from epoxy-fiberglass strip. The coils were assembled and tested in our 2-m-diam cryostat to verify their operation.

Date: September 22, 1980

Creator: Zbasnik, J. P.; Cornish, D. N.; Scanlan, R. M.; Jewell, A. M.; Leber, R. L.; Rosdahl, A. R. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Development of a three-dimensional model of the atmospheric boundary layer using the finite element method

This report summarizes our current effort and ideas toward the development of a model for the planetary boundary layer using the finite element technique. As an initial step, the finite element methodology is applied to simpler version of the boundary layer equations given by the two-dimensional, constant-property, incompressible conservation equations (Navier-Stokes equations). Solution procedures for both the steady-state and transient equations are discussed. For the transient problem, a variable time-step, trapezoid-rule algorithm with dynamic time-truncation error control is presented. The resulting system of nonlinear algebraic equations is solved by a Newton iteration procedure with a frontal solution scheme used for the linear set of equations. The need to develop a suitable linear equation solver, with respect to minimization of computer storage and execution costs, particularly for large (three-dimensional) finite element problems, is also discussed.

Date: November 22, 1977

Creator: Lee, R. L. & Gresho, P. M.

Object Type: Report

System: The UNT Digital Library

(open access)

Estimating Adipose Tissue in the Chest Wall Using Ultrasonic and Alternate /sup 40/K and Biometric Measurements

The percentage of adipose (fat) tissue in the chest wall must be known to accurately measure Pu in the human lung. Correction factors of 100% or more in x-ray detection efficiency are common. Methods using simple /sup 40/K and biometric measurement techniques were investigated to determine the adipose content in the human chest wall. These methods predict adipose content to within 15% of the absolute ultrasonic value. These new methods are discussed and compared with conventional ultrasonic measurement techniques. (ERB)

Date: January 22, 1982

Creator: Anderson, A. L. & Campbell, G. W.

Object Type: Article

System: The UNT Digital Library

(open access)

Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system

A loss-of-coolant accident (LOCA) in a boiling-water-reactor (BWR) power plant has never occurred. However, because this type of accident could be particularly severe, it is used as a principal theoretical basis for design. A series of consistent, versatile, and accurate air-water tests that simulate LOCA conditions has been completed on a /sup 1///sub 5/-scale Mark I BWR pressure-suppression system. Results from these tests are used to quantify the vertical-loading function and to study the associated fluid dynamics phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variation of hydrodynamic-generated vertical loads with changes in drywell-pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the /sup 1///sub 5/-scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings that are invariant. These groupings show that, if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor and occurs in a time reduced by the square root …

Date: December 22, 1977

Creator: Pitts, J.H. & McCauley, E.W.

Object Type: Article

System: The UNT Digital Library

(open access)

Numerical solution of the Schroedinger integral equation for dt. mu. Progress report

The Schroedinger Integral Equation is derived for an N-body system, and solutions for required Green's functions are obtained. The initial method of numerical solution has yielded the correct ground states and lower excited states of He (test case) and dt..mu... Steps are being taken to improve the numerical accuracy.

Date: August 22, 1986

Creator: Morgan, D.L. Jr.

Object Type: Report

System: The UNT Digital Library

(open access)

Radioactivity in gaseous waste discharged from the separations facilities during fourth quarter of 1979

This document is issued quarterly for the purpose of summarizing the radioactive gaseous wastes that are discharged from the facilities of the Rockwell Hanford Operations (Rockwell). Data on alpha and beta emissions during 1979 are presented where relevant to the gaseous effluent. Emission data are not included on gaseous wastes produced within the 200 areas by other Hanford contractors.

Date: February 22, 1980

Creator: Sliger, G. J.

Object Type: Report

System: The UNT Digital Library

(open access)

Review of issues relevant to acceptable risk criteria for nuclear waste management

Development of acceptable risk criteria for nuclear waste management requires the translation of publicly determined goals and objectives into definitive issues which, in turn, require resolution. Since these issues are largely of a subjective nature, they cannot be resolved by technological methods. Development of acceptable risk criteria might best be accomplished by application of a systematic methodology for the optimal implementation of subjective values. Multi-attribute decision analysis is well suited for this purpose.

Date: February 22, 1978

Creator: Cohen, J.J.

Object Type: Article

System: The UNT Digital Library

captions transcript

[News Clip: Eye gouge]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: September 22, 1994, 10:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Apt shooting]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: October 22, 1994, 6:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Stadium drive]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: March 22, 1994, 10:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Stalker]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: July 22, 1994, 6:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Crime bill]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: August 22, 1994, 5:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

captions transcript

[News Clip: Kidnapping]

Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.

Date: October 22, 1994, 6:00 p.m.

Creator: KXAS-TV (Television station : Fort Worth, Tex.)

Object Type: Video

System: The UNT Digital Library

(open access)

Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions on an anisotropic, attractive surface, whereas NH{sub 2} quenching appears to depend on state-mixing considerations, not dynamic control. This state-specific behavior of these small, theoretically tractable hydrides has direct ramifications for quantitative flame diagnostics. Our other effort in the diagnostic area has been repeated but unsuccessful searches for laser induced fluorescence in the vinyl radical.

Date: January 22, 1991

Creator: Crosley, D.R.

Object Type: Report

System: The UNT Digital Library

(open access)

Analysis of the role of an interfacility SNM accounting system

Lawrence Livermore National Laboratory (LLNL) undertook the task of analyzing the actual and potential value of an interfacility NRC material accounting system in deterring and detecting both material diversion and facility material accounting data falsification. The most important conclusion is that only relatively minor changes are needed to upgrade the current NRC interfacility reporting system. The emphasis of the task was on evaluating the usefulness of an NRC-monitored material accounting information system in providing protection against accounting fraud at the plant management or corporate level. The Nuclear Materials Management and Safeguards System (NMMSS) and the NRC Safeguards Status Report System (SSRS), the principal constituents of the current interfacility NRC material accounting information system, are described. Their relationship is shown in two information flow diagrams. Deterministic accounting checks and balances are discussed, both for the current NRC interfacility material accounting system and for an upgraded system. Detection mechanisms are described that would use currently available data and that could be exercised by the NRC in its safeguards management role. Additional checks and balances are recommended, with corresponding changes in data reporting requirements, to upgrade NRC interfacility material accounting system.

Date: February 22, 1982

Creator: McDonnel, J. L.; Chilton, P. D.; Kufahl, G. E.; Vergari, A. A. & Dunn, D. R.

Object Type: Report

System: The UNT Digital Library

(open access)

Scaling of exploding pusher targets

A theory of exploding pusher laser pusher targets is compared to results of LASNEX calculations and to Livermore experiments. A scaling relationship is described which predicts the optimum target/pulse combinations as a function of the laser power.

Date: August 22, 1977

Creator: Nuckolls, J.H.

Object Type: Article

System: The UNT Digital Library

(open access)

Stability of space-charge neutralized beams

Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.

Date: September 22, 1977

Creator: Turnbull, R. J. & Hooper, E. B. Jr.

Object Type: Article

System: The UNT Digital Library

(open access)

Improved methods for computing masses from numerical simulations

An important advance in the computation of hadron and glueball masses has been the introduction of non-local operators. This talk summarizes the critical signal-to-noise ratio of glueball correlation functions in the continuum limit, and discusses the case of (q{bar q} and qqq) hadrons in the chiral limit. A new strategy for extracting the masses of excited states is outlined and tested. The lessons learned here suggest that gauge-fixed momentum-space operators might be a suitable choice of interpolating operators. 15 refs., 2 tabs.

Date: November 22, 1989

Creator: Kronfeld, A.S.

Object Type: Article

System: The UNT Digital Library

(open access)

Recovery of cesium, technetium, rhodium and palladium from stored waste supernates

The results of our assessment of the processing methods and costs for the recovery of cesium, techneium, rhodium, and palladium from aged waste supernates are presented. Guidelines for the assessment of costs are given. Cesium can be readily absorbed from alkaline waste supernates without prior treatment using Linde AW-500, a synthetic zolite. Technetium, present in the supernate as the pertechnetate anion, together with rhodium and palladium, probably present as anionic nitrite complexes, can be absorbed from untreated waste supernates using Dowex 1-X4 or similar anion resins. Although the behavior of cesium and technetium is reasonably well understood, the behavior of the anionic complex that accounts for the presence of rhodium and palladium in this strongly alkaline solution is not well understood. Further work is required before a process can be outlined for the clean separation of rhodium and palladium from the technetium-rhodium-palladium crude fraction sorbed on the anion resin. An assessment of capital and operating costs for the recovery of cesium only, technetium only, or both cesium and technetium are tabulated. No costs are shown for rhodium and palladium, since the technology for their separation is not sufficiently advanced. However, the incremental cost for their separation from technetium is expected …

Date: June 22, 1966

Creator: unknown

Object Type: Report

System: The UNT Digital Library

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