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 Effects of Neutron Irradiation on High Temperature Superconductors written by John J. Hammerer and published by . This book was released on 1988 with total page 51 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.
Download or read book Study of High Magnetic Field and Neutron Irradiation Effects on the Thermal Conductivity of High Tc Superconductors written by Sawako Nakamae and published by . This book was released on 1999 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Stoichiometry and Neutron Irradiation in Superconducting A 15 Compounds written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The A-15 (A3B) compounds comprise an important class of superconducting compounds. In order to gain a clearer understanding of the parameters influencing the superconductivity in these materials, several A-15 compounds have been prepared and the effects of varying stoichiometry, heat treatment, and irradiation with high energy neutrons (E> 1 MeV) on the superconducting transition temperature T/sub c/, Bragg--William order parameter S, and the lattice parameter a0, have been studied. The systems investigated include Nb3Ge, Nb3Al, Nb3Pt, Nb3Ir, V3Ga, V3Si and Mo3Os. Some of the results may be summarized as follows: 1) for Nb3Al, Nb3Pt and V3Ga, T/sub c/ is a strong function of composition, reaching a maximum value at the ideal stoichiometric composition of 3A: 1B, if that composition exists in the equilibrium phase diagram, 2) irradiation with high energy neutrons at temperatures of approx. 150°C results in drastic lowering of T/sub c/ for Nb3Al, Nb3Pt and Nb3Ge, but not for Mo3Os, 3) T/sub c/ can be recovered by annealing, the recovery temperature being in the range 300-800°C depends on the particular compound, 4) the order parameter S, decreases with increasing neutron fluence (decreasing T/sub c/), and is also recoverable upon annealing at the appropriate temperature, 5) the lattice parameter a0, increases with increasing neutron fluence, and isalso restored to its original value by annealing. A simple hard sphere model is developed to calculate the dependence of a0 on composition within the A-15 phase. Excellent agreement is obtained for the measured values in the Nb--Al, Nb--Pt and V--Ga systems. The results of both compositionally and irradiation induced disorder can be understood on the basis of site-exchange taking placee between the A and B sites in the A-15 structure.
Download or read book Irradiation Effects and Cationic Disorder in HTS written by A. V. Narlikar and published by Nova Biomedical Books. This book was released on 2003 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of High Temperature Superconductors, Volume 47 - Irradiation Effects & Cationic Disorder in HTS
Download or read book Studies of High Temperature Superconductors written by A. V. Narlikar and published by . This book was released on 1992 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Six papers by physicists from the Japan, India, Brazil and the US address some of the broad frontal issues of superconductivity, which include the mechanisms of high-temperature superconductivity, extra-high-temperature phenomena, the normal state pseudogap, the observations of the isotope effect in a host of different superconducting systems and their explanations, and the unusual features of strongly correlated electron systems like heavy fermions. Two extended papers explore the importance of positron annihilation and using electron spin resonance techniques to study superconducting materials. The treatments should be accessible to working scientists and engineers and to graduate students of physics, chemistry, materials science, solid-state electronics, and other disciplines.
Download or read book High temperature Superconductivity Bhtsc 92 Proceedings Of The Beijing International Conference written by Z X Zhao and published by World Scientific. This book was released on 1993-10-13 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume will contain both invited and contributed papers which focus on the search for new high-Tc materials, characterization of their physical properties and microstructures, basic applications and the application of high-Tc superconductors.
Download or read book Effects of Low temperature Fusion Neutron Irradiation on Critical Properties of a Monofilament Niobium tin Superconductor written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this work was to irradiate a Nb3Sn superconductor with 14.8 MeV neutrons at 4 K and measure critical current in transverse fields of up to 12 T, irradiating up to a fluence sufficient to decrease the critical current to below its initial value. Critical temperatures were also to be measured. The samples were to be kept near 4 K between the irradiation and the measurement of critical properties. This work is directed toward establishing an engineering design fluence limit for Nb3Sn when used in fusion reactor superconducting magnets.
Download or read book Critical Current Limitation In High Temperature Superconductors written by Waldemar Gorzkowski and published by World Scientific. This book was released on 1992-03-27 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume will focus on the theory and experiments leading to quantitative understanding of the magnetic field and temperature dependence of critical current densities in high-temperature superconductors. Topics will include: critical currents and flux-pinning, flux flow and flux creep, anisotropy of critical fields and currents, properties of the flux lattice and the irreversibility line, magnetization, granularity.
Download or read book Physics and Materials Science of High Temperature Superconductors II written by R. Kossowsky and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 798 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physics and Materials Science of High Temperature Superconductors, II represents the results of a fruitful dialogue between physicists and materials scientists which took place under the auspices of a NATO Advanced Study Institute in Porto Carras, Greece, between 18 and 31 August, 1991. It builds on and carries forward the success of NATO ASI 181 published in 1990. The theoretical side of the discussions reveal the basic premise of the phenomenological and Ginzburg-Landau theories of superconductivity, the implications of short coherence length, long penetration depth, the melting of flux lattices, and other matters, while the materials science includes discussions of microstructures, local inhomogeneities, deviations from ideal chemistry, the effects of systematic errors in materials preparation, the definition of imperfections, and the utilization of common materials analysis techniques. The reader will be made aware of the potential significance of Angstrom scale structural and chemical details, and the need to consider basic theoretical concepts when designing procedures to process viable, solid conductors, specifically the effects of oxygen stoichiometry and deviations from it, as well as the microstructural demands on pinning in the light of very short coherence lengths.
Download or read book The Effects of Neutron Irradiation Damage on the Superconducting Properties of Nb3Sn written by R. Bett and published by . This book was released on 1973 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book High energy Neutron Irradiation of Superconducting Compounds written by and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of high-energy neutron irradiation (E greater than 1 MeV) at ambient reactor temperatures on the superconducting properties of a variety of superconducting compounds is reported. The materials studied include the A-15 compounds Nb3Sn, Nb3Al, Nb3Ga, Nb3Ge and V3Si, the C-15 Laves phase HfV2, the ternary molybdenum sulfide Mo3Pb$sub 0$.5S4 and the layered dichalcogenide NbSe2. The superconducting transition temperature has been measured for all of the above materials for neutron fluences up to 5 x 1019 n/cm2. The critical current for multifilamentary Nb3Sn has also been determined for fields up to 16 T and fluences between 3 x 1017 n/cm2 and 1.1 x 1019 n/ cm2. (auth).
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 1102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Neutron Irradiation and Co doping on Polycrystalline Copper Oxide Superconductors written by Nobuyuki Tsuchiya and published by . This book was released on 1998 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Report on the Effects of Neutron Radiation on Structural Materials written by M. Kangilaski and published by . This book was released on 1967 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Superconductivity and Atomic Ordering in Neutron irradiated Nb sub 3 Ge written by and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of high energy (E> 1 MeV) neutron irradiation on the properties of Nb/sub 3/Ge prepared by chemical vapor deposition have been studied. Irradiation to a fluence of 3.4 x 10/sup 19/ n/cm/sup 2/ produces a decrease in the superconducting transition temperature T/sub c/ from 20.9 to 4.4 K and in the long-range order parameter S from 0.86 to 0.46, and an increase in the lattice parameter a/sub 0/ from 5.142 A to 5.174 A. For a fluence of 6.5 x 10/sup 19/ n/cm/sup 2/, most of the Nb/sub 3/Ge is transformed into a noncrystalline phase. The A15 phase is recovered after annealing.
Download or read book Neutron Irradiation Effects on Superconducting and Stabilizing Materials for Fusion Magnets written by W. Maurer and published by . This book was released on 1984 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:
