Download or read book Effects of Fast neutron Irradiation and High Temperature on Beryllium Oxide written by R. P. Shields and published by . This book was released on 1962 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Fast Neutron Irradiation and High Temperature on Beryllium Oxide written by and published by . This book was released on 1962 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Specimens of 0.428 to 1.18 in. dia. BeO were irradiated at 1.4 x 10/sup 20/ to 2.8 x 10/sup 21/ fast neutrons/cm/ (>1 Mev), with irradiation times of 2.03 x 105 to 5.60 x 106 sec, at 110 to 1025 C, and gamma heat generation rates of 18 to 25 w/g. The greatest damage appeared in bodies irradiated for high neutron doses at low temperatures. Greater doses could be tolerated at higher temperatures. Specimens irradiated at 110 deg C powdered at an accumulated dose of 1.5 x 10/sup 21/ 1.1 x 10/sup 21/ neutrons/cm/sup 2/ and at 737 deg C at a dose of 1.6 x 10 /sup 21/ neutrons/cm/sup 2/ remained intact. Specimens irradiated at 827 to 950 deg C at a dose of 2.1 to 2.6 x 10/sup 21/ neutrons/cm/sup 2/ fractured. Changes in linear dimensions up to 4% were observed. X-ray diffraction measurements revealed changes in the c lattice parameter up to 7 x 10-3 DELTA c/c0 for material irradiated at 110 deg C but only 1 to 2 x 10-3 DELTA c/co at 444 to 1025 deg C. The DELTA c/c0 value appeared to saturate at a dose of 3 x 10/sup 20/ neutrons/cm/sup 2/ in the latter temperature range. All temperatures above 444 deg C were equally effective in suppressing the DELTA c/c0 values. Changes in the a parameter were smaller by a factor of 7. He was retained even at irradiation temperatures of 1025 deg C. Gases could be removed only by dissolving the BeO in fused salt. The He content of the BeO varied linearly with fast-neutron dose up to 1.6 x 10/sup 21/ neutrons/ cm/sup 2/, with a slope of 205 standard mu l per g of BeO per 10 neutrons/cm/sup 2/. The tritium content of BeO irradiated at 110 deg C followed a (neutrons/cm) curve up to 6.4 ppm at 2.1 x 10 neutrons/cm/sup 2/. Specimens irradiated above 444 deg C contained much less tritium. Voids 0.1 to 0.3 mu in diameter which were not in the original material were found by electron microscopy in the interior of grains and at grain boundaries. No evdence of chemical decomposition was observed. Radial temperature differences during irradiation increased by 50 to 100%, indicating a decrease in thermal conductivity. It was concluded that the observed changes could be caused either by gas generation or atomic displacements. The hypothesis that thermal stress alone produced failure was rejected. Results indicate that great caution must be exercised in designing BeO moderators for nuclear reactors. Under some conditions physical deterioration occurs to such a degree as to render the material unsuitable for use. For greatest life the moderator should be kept above 400 deg C, and probably 800 to 1000 deg C is more desirable. The design of the irradiation assembly is described. Temperatures were controlled by varying the composition of a helium- argon mixture in an annulus. Sixtythree specimens were irradiated in six assemblies. (auth).
Download or read book Irradiation of Sintered Beryllium Oxide to High Fast Neutron Doses at 110 650 and 1100 Deg C written by and published by . This book was released on 1964 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Radiation on Metals and Other High Melting Materials written by Vladimir Vladimirovich Penʹkovskiĭ and published by . This book was released on 1964 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Neutron Irradiation on the Thermal Conductivity of Beryllium Oxide written by M. K. Cooper and published by . This book was released on 1963 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Summary of Radiation Effects on Thermionic Insulator Materials written by John T. Mayer and published by . This book was released on 1968 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1971 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: NSA is a comprehensive collection of international nuclear science and technology literature for the period 1948 through 1976, pre-dating the prestigious INIS database, which began in 1970. NSA existed as a printed product (Volumes 1-33) initially, created by DOE's predecessor, the U.S. Atomic Energy Commission (AEC). NSA includes citations to scientific and technical reports from the AEC, the U.S. Energy Research and Development Administration and its contractors, plus other agencies and international organizations, universities, and industrial and research organizations. References to books, conference proceedings, papers, patents, dissertations, engineering drawings, and journal articles from worldwide sources are also included. Abstracts and full text are provided if available.
Download or read book Structural Materials for Generation IV Nuclear Reactors written by Pascal Yvon and published by Woodhead Publishing. This book was released on 2016-08-27 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Operating at a high level of fuel efficiency, safety, proliferation-resistance, sustainability and cost, generation IV nuclear reactors promise enhanced features to an energy resource which is already seen as an outstanding source of reliable base load power. The performance and reliability of materials when subjected to the higher neutron doses and extremely corrosive higher temperature environments that will be found in generation IV nuclear reactors are essential areas of study, as key considerations for the successful development of generation IV reactors are suitable structural materials for both in-core and out-of-core applications. Structural Materials for Generation IV Nuclear Reactors explores the current state-of-the art in these areas. Part One reviews the materials, requirements and challenges in generation IV systems. Part Two presents the core materials with chapters on irradiation resistant austenitic steels, ODS/FM steels and refractory metals amongst others. Part Three looks at out-of-core materials. Structural Materials for Generation IV Nuclear Reactors is an essential reference text for professional scientists, engineers and postgraduate researchers involved in the development of generation IV nuclear reactors. Introduces the higher neutron doses and extremely corrosive higher temperature environments that will be found in generation IV nuclear reactors and implications for structural materials Contains chapters on the key core and out-of-core materials, from steels to advanced micro-laminates Written by an expert in that particular area
Download or read book Publications Reports and Papers for 1961 from Oak Ridge National Laboratory written by Oak Ridge National Laboratory and published by . This book was released on 1965 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Neutron Irradiation on High Temperature Superconductors written by John J Hammerer (Jr) and published by . This book was released on 1988 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt: Neutron irradiation of high temperature superconductors was performed in order to determine the effects of nuclear weapons on these novel materials. This radiation could also be encountered in space radiation belts, fusion reactors and particle accelerators. Fluences used were on the order of 10 to the 18th power fast and thermal neutrons/sq cm. The result of the irradiation was a complete loss of observed superconductivity in YBa2Cu3O7 and ErBa2Cu3O7. A combination of gamma heating of 5 W/g and fast neutron flux imposed serve thermal stress on sample pellets. In two cases, the pellets were reduced to powder. Samples were prepared at the Naval Research Laboratory and the National Research Laboratory and the National Bureau of Standards. They were checked for the Meissner effect using magnetic levitation. The dc four terminal method was used to determine the transition temperature. Keywords: Yttrium compounds; Erbium compounds; Barium oxides; Copper compounds; Radiation effects; High temperature superconductivity. (JHD).
Download or read book The Fast neutron Multiplication Effect of Beryllium in Reactors written by W. Häfele and published by . This book was released on 1959 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Some Effects of Neutron Irradiation on Selected Beryllia Materials written by J. Martin Tobin and published by . This book was released on 1962 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science and Engineering written by and published by . This book was released on 1966 with total page 660 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications Reports and Papers for 1965 from Oak Ridge National Laboratory written by K.O. Johnsson and published by . This book was released on 1966 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reactor Materials written by and published by . This book was released on 1962 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Beryllium Oxide written by Robert Smith and published by . This book was released on 1964 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:
