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73,051 Matching Results

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(open access)

Cosmic ray events in Soudan 2

The Soudan 2 detector is located at a depth of 2090 meters-water equivalent (mwe). About 2 million muon events have been recorded. Here we report on our plans to analyze them for comparison with expectations from atmospheric cosmic ray models. Plans and capabilities to analyze multiple muons and monopoles are also discussed. 3 refs., 5 figs.

Date: August 23, 1989

Creator: Allison, W. W. M.; Alner, G. J.; Ambats, I.; Ayres, D.; Balka, L.; Barr, G. D. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

40-kV, 25-ms neutral-beam power supply for TMX

Modifications are described to upgrade the neutral-beam power supply for the TMX from 40 kV, 10 ms to 40 kV, 25 ms. The redesign of the accel and suppressor power supplies to achieve separation of the high-voltage and control sections, operation of the arc pulse lines in series, operation of the arc pulse lines in a noisy environment with SCR trigger and crowbar, and modifications to the electrolytic storage banks are discussed.

Date: September 23, 1977

Creator: Leavitt, G.A.

Object Type: Article

System: The UNT Digital Library

(open access)

Nuclear design of fast hybrid blankets

The objective of this presentation is to: (1) present the physical motivation for fusion-fission hybrids, (2) outline design considerations for hybrid blankets, and (3) discuss the nuclear performance potential of hybrid blankets.

Date: January 23, 1978

Creator: Lee, J. D.

Object Type: Article

System: The UNT Digital Library

(open access)

Studies of. mu. prime s underground with the Soudan 2 Tracker

During the period July 1987 through March 1988, a section of the Soudan 2 active shield known as the Tracker' recorded {approximately}250,000 muon tracks. The detector is located in the Tower-Soudan State Park in Soudan, Minnesota USA at a depth of 2090 meters-water equivalent. We have analysed the data collected and searched for time-dependent astronomical sources. Distributions in azimuthal and zenith angles as well as declination and right ascension are shown. 1 ref., 7 figs., 1 tab.

Date: August 23, 1989

Creator: Kochocki, J.; Benjamin, D.; Ewen, B.; Kafka, T.; Mann, A.; McMaster, L. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Heat transfer in inertial confinement fusion reactor systems

The short time and deposition distance for the energy from inertial fusion products results in local peak power densities on the order of 10/sup 18/ watts/m/sup 3/. This paper presents an overview of the various inertial fusion reactor designs which attempt to reduce these peak power intensities and describes the heat transfer considerations for each design.

Date: April 23, 1980

Creator: Hovingh, J.

Object Type: Article

System: The UNT Digital Library

(open access)

Progress report for the Division of Safeguards and Security: January--June 1977

Development of the calorimeter equilibrium prediction program has been completed, and tests of the software program have been conducted on calorimeters ranging from 1 to 6 in. (2.5 to 15 cm) in diameter and power inputs between 0.1 and 8.3 W. Equilibrium values have been predicted with relative accuracies of better than 0.1% (95% confidence) and with an average time improvement factor of 2.1, which represents a 52% time saving, for every test case. A computer code is being developed by the University of Cincinnati to describe the steady-state heat transfer in a resistance bridge calorimeter. The computer program which is based on the theory of heat transfer analysis by finite differences has been written and is being checked against experimental data. Following the development of the steady-state code, work will commence on the transient heat flow analysis. The effect of R. Gunnink's new plutonium branching ratios on previous plutonium isotopic ratio measurements is demonstrated. For measurements relative to plutonium-239 the biases change from between 2 and 7% low to between 2 and 13% high. For measurements relative to plutonium-241 the changes in bias are within the statistical uncertainties normally reported for these peaks. In preparation for the proposed demonstration …

Date: December 23, 1977

Creator: Ratay, R.P. (ed.)

Object Type: Report

System: The UNT Digital Library

(open access)

Evaluation of Effectiveness of the Turco Low Profile Turbulator Reg Sign

This document discusses a turbulator which utilizes a heated chemical bath to reduce smearable contamination from small parts and tools. It is comprised of two agitators programmed to automatically alternate the flow of the cleaning solution within the tank in four separate and distinct high velocity flow patterns allowing access to the entire surface area of the part or tool being decontaminated. The turbulator is being evaluated to determine if agitation increases the effectiveness of waste minimization. Testing of the turbulator consisted of evaluation of the Sludgetrap Containment, Tool Cleaning Demonstration, and Coupon Testing. Results so far are that the sludgetrap is effective in containing particles the size of sand, agitation increases the effectiveness of the turbulator, abrasives can replace detergents for waste minimization, and Inconel 625 is more difficult to clean than Type 3041 Stainless Steel.

Date: October 23, 1990

Creator: Grittmann, S.; McGlynn, J. F.; Long, J. R. & Rankin, W. N.

Object Type: Report

System: The UNT Digital Library

(open access)

Heat transfer research and power cycle transient modeling

Fine axial flutes enhance heat transfer in vertical shell-and-tube exchangers with water inside the tubes and ammonia evaporating or condensing in layer flow on the shell side. Single-tube experiments with R-11 and ammonia indicate local shell-side coefficients 3 to 5 times those for corresponding smooth tubes. Single-tube experiments with water indicate that at moderate velocities the tube-side coefficients are enhanced by a factor equal to the ratio of fluted-to-smooth surface areas while the fluid friction is similarly increased. The experimental data are transformed into mean individual coefficients for ammonia and water. Overall coefficients for a particular case are presented to illustrate the efficacy of enhancement by flutes on one or both sides of the heat transfer surface. Means are described for using emerging data to predict the static and dynamic behavior of the power cycle and the interactions of components throughout the complete power plant.

Date: March 23, 1977

Creator: Rothfus, R.R. & Neuman, C.P.

Object Type: Article

System: The UNT Digital Library

(open access)

Tandem mirror reactors with thermal barriers

Preliminary calculations of Q and magnet designs are presented for three different versions of tandem mirror reactors (TMR) using thermal barriers to enhance plug potentials by auxiliary electron heating. These three versions, called A-cell-barrier TMR, axisymmetric-barrier TMR, and inside-barrier TMR, exhibit reduced plug density (n/sub p/ << 10/sup 19/ m/sup -3/) and less required magnetic mirror field (B/sub mirror approx. = 9 T) compared to TMR designs without thermal barriers. A-cell barrier TMR Q's range from 5 to 25 depending on the central-cell length (L/sub c/ = 100 to 200 m) and peak center-cell beta ..beta../sub c/ (0.3 to 0.7) allowed by MHD stability. Axisymmetric-barrier TMR Q's range from 14 at L/sub c/ = 100 m to 30 at L/sub c/ = 200 m, if peak ..beta../sub c/ = 1. From a global equilibrium model for the inside-barrier TMR, Q values greater than 15 are achieved for ..nu.. = 0.5 in the modified Boltzmann relation for the plug potential. Even higher Q's are obtained using ECRF heating in the barrier to create a hot, mirror-trapped electron population. TMR's burning D-D as a fuel have been analyzed with a modified version of the global equilibrium model and under the assumption of …

Date: May 23, 1980

Creator: Logan, B. G.; Arfin, B. & Barr, W. L.

Object Type: Article

System: The UNT Digital Library

(open access)

Evaluation of extraction chromatography for americium recovery

Extraction, or reverse-phase partition chromatography, as used mostly for analytical separations, employs an organic solvent extractant as a stationary phase on an inert support material. This technique, which has the advantage of utilizing the versatility of solvent extraction systems with the less expensive operation of ion exchange equipment, was evaluated for a process to recover low level concentrations of americium from acidic process waste streams at Rocky Flats. The bidentate organophosphorous extractant DHDECMP (dihexyl-N, N-diethylcarbamylmethylene phosphonate) was used as the stationary phase since it was shown to effectively scavenge americium from acidic waste streams without significantly extracting impurity ions. Over 30 support materials were evaluated for DHDECMP capacity and for their ability to retain the extractant. Of the supports tested, the Amberlite XAD macroreticular sorbents were found to have the highest DHDECMP capacity. Amberlite XAD-4 beads retained the extractant significantly better than the other supports evaluated. Thus, this solvent was tested for americium breakthrough capacity and compared to the theoretical capacity.

Date: March 23, 1977

Creator: Alford, C. E. & Navratil, J. D.

Object Type: Report

System: The UNT Digital Library

(open access)

Vapor Containment in the Oak Ridge Research Reactor

Containment of the ORR is attained by means of a ventilation system which is capable of exhausting air from the building at a rate sufficient to ensure that all leakage of air at ground level is into the building. The exhaust air is treated by scrubbing and filtration and is discharged from a large stack at a height and velocity sufficient to guarantee that meteorological dispersion will reduce the resulting concentration of radioactive material to an acceptable level. Factors involved in selection of this type of controlled containment are discussed. Original design and modifications are described. Performance is also discussed. (M.C.G.)

Date: August 23, 1962

Creator: Binford, F.T.

Object Type: Report

System: The UNT Digital Library

(open access)

Calculation of Doppler Coefficient and Other Safety Parameters for a Large Fast Oxide Reactor

Several safety parameters are calculated for a large, fast, Na-cooled, oxide-fueled reactor. The Doppler coefficient is studied as regards its effect on the reactivity during a power excursion, and its dependence on the neutron spectrum, on the concentrations of U/sup 238/, Pu /sup 239/ , a nd Pu/sup 240/, on spatial temperature and power distributions, and on temperature. Other parameters studied include the Na temperature coefficient of reactivity, and the reactivity insertion caused by total Na loss; reactivity coefficients caused by thermal expansion of fuel and steel cladding; the excess operating reactivity; and the reactivity caused by a fuel slump. The effects of a Be reflector on neutron lifetimes are determined. The safety aspects are balanced against economic considerations. (T.F.H.)

Date: March 23, 1961

Creator: Greebler, P.; Hutchins, B. A. & Sueoka, J. R.

Object Type: Report

System: The UNT Digital Library

(open access)

Revegetation of Alaskan coal mine spoils. Progress report

Activities initiated after the start of the revegetation project on Alaskan coal mine spoils on September 1, 1979 have consisted mainly of some fall plantings (dormant seedings) and soil and coal spoil samplings and analyses. Because of the late summer start for the project, only a limited amount of field work could be initiated in plant material studies. This consisted of a fall planting at the Usibelli mine site at Healy in interior Alaska. The planting was intended to test the efficacy of seeding in the frost period following the growing season, requiring the seed to remain dormant over winter and to germinate when conditions become favorable in late spring. It also was intended as a comparison of a number of different grasses. Thirty entries were seeded in three replications. Fifteen species of grasses and a clover were included in the trial. The site provided for the trial was on overburden material along a streambed. Among the entries were eight cultivars of introduced grasses, five cultivars of native Alaskan germplasm, one introduced clover cultivar, and sixteen experimental grasses mainly of Alaskan origin.

Date: May 23, 1980

Creator: Mitchell, W W; Mitchell, G A & McKendrick, J D

Object Type: Report

System: The UNT Digital Library

(open access)

Evaluation of low activation vanadium alloys for structural material in a fusion reactor

The V-7.2Cr-14.5Ti, V-9.2Cr-4.9Ti, V-9.9Cr-9.2Ti, V-13.5Cr-5.2Ti, V-4.1Cr-4.3Ti, Vanstar-7, V-4.6Ti, V-17.7Ti, and V-3.1Ti-(0.5-1.0)Si alloys were evaluated for use as structural material in a fusion reactor. The alloys were evaluated on the basis of their yield strength, swelling resistance, resistance to hydrogen and irradiation embrittlement, and compatibility with a lithium reactor coolant. On the basis of these evaluations, the V-7.2Cr-14.5Ti, V-9.2Cr-4.9Ti, V-9.9Cr-9.2Ti, V-13.5Cr-5.2Ti, Vanstar-7, and V-3.1Ti-(0.5-1.0)Si alloys are considered unacceptable for structural material in a fusion reactor, whereas the V-4.1Cr-4.3Ti, V-4.6Ti, and V-17.7Ti alloys are recommended for more intensive evaluation. The V-7Cr-5Ti alloy may have the optimum combination of strength, DBTT, swelling rate, and lithium dissolution rate for a structural material in a fusion reactor. 4 refs., 6 figs., 4 tabs.

Date: October 23, 1989

Creator: Loomis, B. A.; Hull, A. B. & Smith, D. L.

Object Type: Article

System: The UNT Digital Library

(open access)

Thermodynamic study of the MWG system/components and measurement of the oxygen partial pressure in the heat source capsule

A thermodynamic study of the Milliwatt Generator heat source capsule was performed to determine the effects of the oxide fuel on container materials at elevated temperatures in order to evaluate the factors affecting embrittlement of T-111 alloy. The study indicates that relatively slow oxidation of the T-111 of the capsule occurs during pretreatment. Yttrium added to the /sup 238/PuO/sub 2/ fuel charge is functioning in its designed role as an oxygen getter and is stabilizing at an O/Pu ratio of 1.75. The free energy of formation of hafnium oxide has been measured and found to be -70632 cal/mole; this suggests that the ability of hafnium to strongly function as an oxygen getter may be largely determined by the kinetics, and the free energy may play a lesser role.

Date: June 23, 1980

Creator: David, D.J.

Object Type: Report

System: The UNT Digital Library

(open access)

(Study of flow properties of wet solids using laser induced photochemical anemometry)

Research continues on the flow properties of wet solids. During this period we have made: progress in the analysis of the accuracy of the technique, progress in firming the foundations of LIPA for Solid-Liquid Mixtures, progress in the construction of better prototype skimmers, continued progress in chemically manufacturing both more red europium imbedded CaF{sub 2} and Green liquid Flowlite, and progress in understanding the coupling of LIPA chemicals snd dynamic range and timing. (VC)

Date: February 23, 1992

Creator: Falco, B.

Object Type: Report

System: The UNT Digital Library

(open access)

Dispersive effects of transverse displacements of SLC Arc magnets

The SLC Arc magnets are subject to random displacements and field errors resulting in unpredictable transverse displacement of the central trajectory from that of the design. The chosen method of correcting this perturbed trajectory in the SLC Arcs utilizes mechanical movement of the combined function magnets which compose the Arc transport lines. Here we present the results of a recent investigation substantiating the earlier results which led to the adoption of this method.

Date: July 23, 1986

Creator: Murray, J. J.; Fieguth, T. & Kheifets, S.

Object Type: Report

System: The UNT Digital Library