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Design, analysis, and testing of a high thermal conductivity waveguide window for use in a free-electron laser

Description: Design, analysis and testing of a waveguide window with a goal of propagating greater than 100 kW average power operating at 1500 Mhz has been performed. This is made possible by the favorable material properties of Beryllia (BeO). Brazing the window to a soft copper frame and then brazing the frame to a KOVAR flange provides the vacuum seal. RF analysis combined with thermal/structural analysis shows the benefits of the material. The KOVAR flange with a CTE,coefficient of thermal expansion, that matches that of BeO enables a strong braze joint. RF testing to 35 kW has been successful, and higher powers will be tested in the near future. The basics of this design can be expanded to applications with lower frequencies and higher average power.
Date: August 1, 1998
Creator: Schultheiss, T.; Christina, V.; Cole, M.; Rathke, J.; Elliott, T.; Nguyen, V. et al.
Partner: UNT Libraries Government Documents Department

GENERAL REACTOR SIZING TECHNIQUES. VOLUME I. AEROTHERMODYNAMIC OPTIMIZATION

Description: A method is presented for the aerothermodynamic optimization of the net power and/or propulsive thrust per unit reactor free flow area of a nuclear power plant operating on the Brayton cycle. A system so optimized will translate into the minimum size, therefore the minimum weight, nuclear system for any selection of reactor materials, lifetime, and fuel loading. The theory and development of the thermodynamic optimization process, the importance and effect of various parameters, and specific methods to be employed in the optimization of the various forms of the Brayton cycle are discussed. A sample calculation for the case of the ramjet application is included. The results of the application of these techniques to any Brayton cycle system may be used in conjunction with nuclear sizing methods, for beryllia-moderated reactors, to determine the required reactor size as a function of fuel loading and reactivity requirements. (auth)
Date: June 1, 1961
Creator: Prickett, W.Z.
Partner: UNT Libraries Government Documents Department

AIRCRAFT NUCLEAR PROPULSION DEPARTMENT NUCLEAR SAFETY GUIDE

Description: The limitations and operating techniques which were in effect at ANPD for the prevention of criticality accidents are summarized. The standards followed by the atomic industry were followed; however, the safe mass of U/sup 235/ moderated with beryllium oxide and hydrogeneous materials was based upon criticality experiments conducted at ANPD. Although the guide was primarily for the use of the ANPD nuclear safety control organization, it may also be of assistance to designers and operating management in maintaining nuclear safety. (auth)
Date: June 1, 1961
Creator: Pryor, W.A.
Partner: UNT Libraries Government Documents Department

THERMAL STRESSES IN HOLLOW CYLINDERS OF BERYLLIUM OXIDE

Description: The problems of experimentally studying the effects of thermal stresses in beryllium oxide are considered in detail. Several ways of producing thermal stresses in hollow cylinders are described and the theoretical stress equations are given for these conditions. Theoretical treatment and practical considerations indicate that an experimental technique involving a static DELTA T and external heating of a hollow cylinder should be the most acceptable experimental approach. (auth)
Date: January 1, 1962
Creator: Swindeman, R.W.
Partner: UNT Libraries Government Documents Department

EXPERIMENTAL BERYLLIUM OXIDE REACTOR PROGRAM. Quarterly Progress Report for the Period, January 1 through March 31, 1962

Description: Progress made in the development of the Experimental Beryllium Oxide Reactor (EBOR) is reported. The objective of the EBOR program is to develop a gas-cooled, beryllium oxide-moderated reactor which can be used in conjunction with a closed-cycle gas turbine or a steam cycle for a small land-based or a maritime power plant. Progress is reported on reactor development, reactor physics, and materials development. (N.W.R.)
Date: April 25, 1962
Partner: UNT Libraries Government Documents Department

Summary of BeO Development Work for the Experimental Beryllium Oxide Reactor Program

Description: The Experimental Beryllium Oxide Reactor is described. The configurations and properties of BeO blocks are discussed. Various BeO shapes were fabricated and tested. BeO specimens of selected compositions and densities were irradiated. Dimensional changes due to radiation were in the range below 1.4% as determined from micrometer measurements. Some of the specimens in the highest exposure region of the capsule exhibited radial fractures. (M.C.G.)
Date: June 28, 1963
Creator: Johnson, D. E.
Partner: UNT Libraries Government Documents Department

Experiments on the Effect of Atomic Electrons on the DecayConstant of Be7 II.

Description: A comparison of the decay constants of Be{sup 7} in beryllium oxide and in beryllium fluoride has given {lambda}{sub BeO}-{lambda}{sub BeF{sub 2}} = (+1.375 {+-} 0.053)10{sup -3}{lambda}{sub BeO} thus showing a definite effect of the chemical binding on the radioactive decay constant.
Date: June 15, 1949
Creator: Leininger, R.F.; Segre, E. & Wiegand, C.
Partner: UNT Libraries Government Documents Department

SOME PROPERTIES OF BERYLLIUM OXIDE

Description: S>The primary objective of the literature search was to determine the best values for the properties involved in the thermal stress parameter. Comparison of data from various investigators indicates that thermal expansion of beryllia is independent of density. A wide variation was found in the thermal conductivity values of beryllia. Graphs and tables are presented which summarize and compare data from various sources. A bibliography of 53 references for some of the major items of the stress parameter (thermal expansion, thermal conductivity, and modulus of elasticity) as well as for general properties of beryllia is given to books, journals, and reports published from 1914 to 1960. (auth)
Date: May 19, 1961
Creator: Lillie, J.
Partner: UNT Libraries Government Documents Department

Final summary of impurities in beryllium oxide as used in the Tory II-A-1 reactor. Pluto technical note No. 257

Description: Declassified 26 Nov 1973.<><DSN>29:020150<ABS>has resulted from a sophisticated consideration of its application as a ramjet engine. An idealized reactor power profile was derived directed toward optimizing the transfer of heat energy to the airstream. Some twenty-six classes of fueled tubes have been used to tailor both axial and radial reactor power profiles accordingly. Procedures for the fabrication of components and assembly of the reactor have consequently become tedious and lengthy to safe-guard agalnst errors. The calculations presented were done to estimate the price, in terms of engine performance, of one simplification in design. At present the Tory II-C reactor has an axial fuel loading pattern with concentrations decreasing in six steps. The simplification considered is the removal of this axial variation while preserving the radial power profile. Neutronics calculations were done with the Angie code to find the resulting power profile. This in turn provided the input for the reactor performance code DASH N. (auth)
Date: February 1, 1962
Creator: Hampel, V.E. & Moran, W.
Partner: UNT Libraries Government Documents Department

Atomic scale enhancement of the adhesion of beryllium films to carbon substrates

Description: We have used 200 keV carbon ions to enhance the adhesion of 240-nm thick Be films to polished, vitreous carbon substrates. Adhesion of the as-deposited films was below that necessary to pass the scotch-tape test. Carbon ion fluences less than 1.6x10{sup 14} C/cm{sup 2} were sufficient to ensure the passage of the tape test without affecting the optical properties of the films. Adhesion failure of the as-deposited film was attributed to an inner oxide layer between the Be and the carbon. Because this oxide ({approximately}5 nm of BeO) was not measurably changed by the irradiation process, these results are consistent with adhesion enhancement occurring on the atomic scale at the interface between the inner oxide and the carbon substrate. This conclusion was supported by Rutherford backscattering (RBS) data, and potential adhesion mechanisms are discussed with consideration of relative contributions from electronic and nuclear stopping.
Date: December 1, 1995
Creator: Musket, R.G. & Wirtenson, G.R.
Partner: UNT Libraries Government Documents Department

A high thermal conductivity waveguide window for use in a free electron laser

Description: Design, analysis, and testing of a waveguide window with a goal of propagating greater than 100 kW average power operating at 1500 Mhz has been performed. This is made possible by the favorable material properties of beryllia (BeO). Brazing the window to a soft copper frame and then brazing the frame to a KOVAR flange provides the vacuum seal. RF analysis combined with thermal/structural analysis shows the benefits of the material. The KOVAR flange with a CTE, coefficient of thermal expansion, that matches that of BeO enables a strong braze joint. RF testing to 35 kW has been successful. The basics of this design can be expanded to applications with lower frequencies and higher average power. A paper similar to this was presented at LINAC 98.
Date: April 1, 1999
Creator: Elliott, T.; Nguyen, V.; Phillips, L.; Lab), J. Preble (Jefferson; Schultheiss, T.; Christina, V. et al.
Partner: UNT Libraries Government Documents Department

Evaluation of High-Fired Beryllium Oxide Digestion Methods to Measure Beryllium in Industrial Hygiene Samples by Inductively Coupled Plasma-Atomic Emission Spectroscopy

Description: Several digestion methods were tested to determine their effectiveness on high-fired BeO (ceramic BeO that has been heated to a temperature of approximately 1450 degrees C). High fired BeO is an extremely insoluble, refractory compound that may be present at some DOE sites. Because of the toxicity of air-borne BeO particulates, detection and measurement of high-fired BeO is required. Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) is a sensitive technique for measuring Be. However, the Be must be dissolved prior to analysis. Accurate detection of the presence of Be depends on digestion methods that are effective for all forms of Be, including high-fired BeO, that may be in Industrial Hygiene (IH) wipes or air filter samples.
Date: November 1, 2004
Creator: Charles, Coleman
Partner: UNT Libraries Government Documents Department

THE FABRICATION AND IRRADIATION TESTING OF DISPERSION-TYPE BeO-UO$sub 2$ CERAMIC FUEL MATERIALS

Description: Considerations affecting the design of dispersion-type ceramic fuel materials are discussed. The results of measurements made to study the effect of fuel loading on the properties of the fuel bodies and the results of irradiation tests of fuel pellets composed of 20 vol% UO/sub 2/ dispersed in BeO are presented. Experience in the fabrication of dispersion-type BeO --UO/sub 2/ ceramic fuel materials is described. From the results obtained, it is believed that BeO --UO/sub 2/ fuel materials of the type studied will exhibit satisfactory performance in the Experimental Beryllium Oxide Reactor. (auth)
Date: October 10, 1962
Creator: Johnson, D E & Lofftus, F H
Partner: UNT Libraries Government Documents Department

THE FAST MULTIPLICATION EFFECT OF BERYLLIUM OXIDE IN REACTORS

Description: The net multiplication effect of beryllium oxide, which is due to the (n,2n) reaction, was calculated using an essentially exact calculation of the neutron spectrum as a function of energy. The upper limit of the (n,2n) cross section curve gives the unpoisoned value epsilon /sup +/ = 1.047 and the lower limit gives epsilon /sup -/ = 1,027. The behavior of the Li/sup 6/poisoned fast multiplication effect as a function of the number of collisions was studied for both beryllium and beryllium oxide. (auth)
Date: December 14, 1959
Creator: Hafele, W. & Tsagaris, M.
Partner: UNT Libraries Government Documents Department

LITERATURE SURVEY OF GASES IN BERYLLIUM. Report to Wright Air Development Division

Description: Structural and thermodynamic properties of beryllium, beryllium-oxygen systems, beryllium-nitrogen systems, and beryllium-hydrogen systems as determined by various researchers are surveyed. Diffusion properties, reaction kinetics, and vapor pressures are given where they were available. 44 references. (D.C.W.)
Date: January 17, 1961
Creator: Pemsler, J.P. & Anderson, R.W.
Partner: UNT Libraries Government Documents Department

Comparison of BEO Versus Graphite as a Moderator for MGCR

Description: The comparison is made on the basis of nuclear requirements, properties, cost, and performance under irradiation. Results of published work were reviewed on the effects of irradiation on beryllium oxide and beryllium oxide - uranium dioxide dispersions. A research proposal for a Maritime Gas-cooled Reaotor Moderator is included. (J.R.D.)
Date: September 11, 1959
Creator: Wallace, W. P. & Simnad, M. T.
Partner: UNT Libraries Government Documents Department