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in subjects: "Beryllium Oxides"

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Nuclear magnetohydrodynamic power plant in space. [URANIUM CARBIDE FUEL]

No Description Available.

Date: March 1, 1964

Creator: Carter, J.C. & Armstrong, R.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development and evaluation of die and container materials. Final report

Specific compositions of high purity silicon aluminum oxynitride (Sialon) and silicon beryllium oxynitride (Sibeon) solid solutions are shown to be promising refractory materials for handling and manipulating solar grade silicon into silicon ribbon. Well controlled processing schedules were developed for fabricating high purity Sialon and Sibeon materials. Essentially the impurity content of the hot pressed ceramics was due only to impurities from the original starting powders. A ceramic shapin… more

Date: May 1, 1979

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advances in materials science, Metals and Ceramics Division. Triannual progress report, October 1979-January 1980

Progress is summarized concerning magnetic fusion energy materials, laser fusion energy, aluminium-air battery and vehicle, geothermal research, oil-shale research, nuclear waste management, office of basic energy sciences research, and materials research notes. (FS)

Date: March 31, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effects of oxide layers on optical properties and x-ray hardness of Al-Be mirrors

Oxide layers form on the surfaces of many metallic mirrors. The oxidation may occur during fabrication or after the mirror is finished and installed. Some oxide layers may be intentionally added to protect the mirror or to change its optical properties. Computer calculations predict the effect of oxide layers on optical and ultraviolet reflectance as well as the x-ray absorption and concomitant thermal damage to the mirrors. 6 refs., 6 figs., 1 tab.

Date: June 11, 1991

Creator: White, R.H. & Wirtenson, G.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Flux at a point in MCNP

The current state of the art of calculating flux at a point with MCNP is discussed. Various techniques are touched upon, but the main emphasis is on the fast improved version of the once-more-collided flux estimator, which has been modified to treat neutrons thermalized by the free gas model. The method is tested on several problems on interest and the results are presented.

Date: January 1, 1980

Creator: Cashwell, E.D. & Schrandt, R.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A gas-cooled cermet reactor system for planetary base power

Fission nuclear power is foreseen as the source for electricity in colonization exploration. A gas-cooled, cermet-fueled reactor is proposed that can meet many of the design objectives. The highly enriched core is compact and can operate at high temperature for a long life. The helium coolant powers a Brayton cycle that compares well with the SP-100-based Brayton cycle. The power cycle can be upgraded further under certain siting-related conditions by the addition of a low temperature Rankine c… more

Date: January 1, 1992

Creator: Jahshan, S.N. & Borkowski, J.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Tokamak first-wall coating program development

The development of a research program to study coatings for control of impurities originating from the first wall of a Tokamak reactor is extensively discussed. The first wall environment and sputtering, temperature, surface chemical, and bulk radiation damage effects are reviewed. Candidate materials and application techniques are discussed. The philosophy and flow chart of a recommended coating development plan are presented and discussed. Projected impacts of the proposed plan include benefi… more

Date: August 1, 1977

Creator: Davis, M. J.; Langley, R. A. & Prevender, T. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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DCT-8 pumped limiter design considerations

Disruption erosion drives the life of the DCT-8 pumped limiter. This result came from an evaluation of beryllium (Be), beryllium oxide (BeO), and silicon carbide (SiC) as candidate surface tile materials. Beryllium oxide was selected as the reference tile materials. Beryllium oxide was selected as the reference tile material because it has the longest life: 13 full power hours (2300 burns at 20 s/burn) or 2.3 years of DCT-8 operation. The fabricability of any of the candidate materials and the … more

Date: January 1, 1983

Creator: Fuller, G. M.; Cramer, B. A. & Haines, J. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High efficiency heat transport and power conversion system for cascade

The Cascade ICF reactor features a flowing blanket of solid BeO and LiAlO/sub 2/ granules with very high temperature capability (up to approx. 2300 K). The authors present here the design of a high temperature granule transport and heat exchange system, and two options for high efficiency power conversion. The centrifugal-throw transport system uses the peripheral speed imparted to the granules by the rotating chamber to effect granule transport and requires no additional equipment. The heat ex… more

Date: February 1, 1985

Creator: Maya, I.; Bourque, R.F.; Creedon, R.L. & Schultz, K.R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ceramic BeO exoelectron dosimeters for tritium and radon monitoring

An environmental monitoring device with BeO ceramic dosimeters can be used to measure /sup 222/Rn in dwellings. Radon diffuses into a porous hemispheric chamber and the radon daughters are electrostatically collected on aluminized Mylar foil covering the BeO dosimeter that records the alpha activity. A 10:1 signal-to-background ratio results from a radon exposure of only pCi-h/l. This high sensitivity makes accurate radon measurement possible within one day, even at near background levels of a … more

Date: January 1, 1979

Creator: Gammage, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cascade ICF power reactor

The double-cone-shaped Cascade reaction chamber rotates at 50 rpm to keep a blanket of ceramic granules in place against the wall as they slide from the poles to the exit slots at the equator. The 1 m-thick blanket consists of layers of carbon, beryllium oxide, and lithium aluminate granules about 1 mm in diameter. The x rays and debris are stopped in the carbon granules; the neutrons are multiplied and moderated in the BeO and breed tritium in the LiAlO/sub 2/. The chamber wall is made up of S… more

Date: May 20, 1986

Creator: Hogan, W.J. & Pitts, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Radiation-induced rf loss measurements and thermal-stress calculations for ceramic windows

Irradiation with high energy neutrons can cause increases in loss tangent and thermal resistivity for some ceramics. Loss tangents over the range 0.02 to several MHz have been measured for single and polycrystalline aluminum oxide and polycrystalline beryllium oxide, after irradiation with a spallation neutron source. Some samples of single crystal aluminum oxide were also irradiated with 14-MeV neutrons at RTNS-II to compare spectral effects. Significant increases in loss tangent were observed… more

Date: January 1, 1983

Creator: Fowler, J.D. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Charge state of sputtered impurity ions near a limiter or divertor in a tokamak

Many impurity atoms sputtered from a limiter or divertor plate are ionized in the scrapeoff zone and return to the sputtering surface bacause of friction with incoming plasma ions. The final charge state attained by such impurities has been calculated for a variety of plasma edge conditions. The surface materials considered are tungsten, beryllium, beryllium oxide, and carbon. Estimates of the successive ionization cross sections for tungsten are developed. In all cases examined, returning impu… more

Date: March 1, 1983

Creator: Boley, C. D.; Brooks, J. N. & Kim, Y. K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Analysis of coatings and thin films using energetic ions

Energetic ion analysis techniques provide nondestructive information on the depth distribution of atomic composition in the near-surface (1 to 10 ..mu..m) region of a solid sample. The techniques are quantitative and are not complicated by the presence of chemical or matrix effects. Generalized nuclear reaction analysis is described and its application to the measurement of the stoichiometry of Ta/sub 2/O/sub 5/ films and BeO coatings on Cu--Be is briefly discussed.

Date: January 1, 1979

Creator: Borders, J. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation induced detrapping of implanted deuterium in BeO by high energy /sup 3/He and proton irradiation

BeO layers formed on Be are implanted with 5 keV deuterium ions and the amount of gas retained is determined using the D(/sup 3/He,H)/sup 4/He nuclear reaction. Detrapping of the retained deuterium by 790 keV /sup 3/He and 2.2 MeV H bombardment is measured at temperatures between 140 and 470/sup 0/K and detrapping cross sections are determined. The maximum detrapping yields found are 17 D//sup 3/He and 0.8 D/H. The results indicate that the observed radiation induced detrapping is caused by ele… more

Date: 1979~

Creator: Scherzer, B. M. U.; Blewer, R. S.; Behrisch, R.; Schulz, R.; Roth, J.; Borders, J. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Oxygen permeability of several ceramic oxides above 1200 degrees C

Oxygen permeability as a function of temperature was measured for several ceramic oxides over the range 1200 to 1700{degrees}C. Of the oxides testbed, alumina, beryllia, yttria, lanthanum halfnate, and calcium zironcate exhibited the lowest permeabilities in order of decreasing resistance to oxygen transport. None of the permeability constants were less than the 10{sup {minus}10} to 10{sup {minus}12} g O{sub 2}/cm {center dot} s needed for a useful protective coating system above 1500{degrees}C… more

Date: January 1, 1992

Creator: Courtright, E.L. & Prater, J.T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Choice of pyroprocess for Integral Fast Reactor fuel

A design objective for the Integral Fast Reactor (IFR) is fuel self sufficiency. This can be achieved only by employing chemical reprocessing as part of the fuel cycle. Because the fuel is a metal alloy (U-Pu-Zr), direct production of metal is highly advantageous. This makes a pyrometallurgical process attractive. (JDB)

Date: January 1, 1985

Creator: Miller, W. E.; Johnson, T. R. & Tomczuk, Z.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermal conductivity of mixed beryllia/Li ceramic in sphere-pac forms

Lithium containing ceramic tritium breeder materials have been envisaged to be deployed within the blanket region of a fusion reactor in several possible configurations. One of these is the sphere-pac configuration. For this configuration an important material parameter is its thermal conductivity (Ksp). It is well known that Ksp demonstrates rather complex behavior as a function of temperature, gas pressure, gas composition, particle size, and packing fraction. The inter-relationship of these … more

Date: January 1, 1986

Creator: Tam, S. W. & Johnson, C. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermal and structural limitations for impurity-control components in FED/INTOR

The successful operation of the impurity-control system of the FED/INTOR will depend to a large extent on the ability of its various components to withstand the imposed thermal and mechanical loads. The present paper explores the thermal and stress analyses aspects of the limiter and divertor operation of the FED/INTOR in its reference configuration. Three basic limitations governing the design of the limiter and the divertor are the maximum allowable metal temperature, the maximum allowable st… more

Date: February 1, 1983

Creator: Majumdar, S.; Cha, Y.; Mattas, R.; Abdou, M.; Cramer, B. & Haines, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ceramics for applications in fusion systems

Six critical applications for ceramics in fusion systems are reviewed, and structural and electrical problem areas discussed. Fusion neutron radiation effects in ceramics are considered in relation to fission neutron studies. A number of candidate materials are proposed for further evaluation.

Date: January 1, 1979

Creator: Clinard, F.W. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Ceramics for fusion applications

Ceramics are required for a variety of uses in both near-term fusion devices and in commercial powerplants. These materials must retain adequate structural and electrical properties under conditions of neutron, particle, and ionizing irradiation; thermal and applied stresses; and physical and chemical sputtering. Ceramics such as Al/sub 2/O/sub 3/, MgAl/sub 2/O/sub 4/, BeO, Si/sub 3/N/sub 4/ and SiC are currently under study for fusion applications, and results to date show widely-varying respo… more

Date: January 1, 1986

Creator: Clinard, F.W. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Radio frequency heating of ceramic windows in fusion applications

Ceramic windows will be used as material barriers for radio frequency plasma heating in fusion reactors. This report examines the theory behind rf heating phenomena. Heating calculations are presented for various window materials, thicknesses, wavelengths, and power densities. The most pertinent material properties are loss tangent, thermal conductivity, dielectric constant, strength, and radiation resistance. Calculations indicate that among candidate materials, beryllium oxide offers the most… more

Date: November 1, 1981

Creator: Fowler, J.D. Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Dielectric changes in neutron-irradiated rf window materials

Ceramics used for windows in ECRH heating systems for magnetically-confined fusion reactors must retain adequate properties during and after intense neutron irradiation. Of particular concern is a decrease in transmissivity, a parameter inversely related to the product of dielectric constant K and loss tangent tandelta. Samples of polycrystalline Al/sub 2/O/sub 3/ and BeO were irradiated to 1 x 10/sup 26/ n/m/sup 2/ at 660K in the EBR-II fission reactor, and the above properties subsequently me… more

Date: January 1, 1987

Creator: Frost, H.M. & Clinard, F.W. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department