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Alternative dipole magnets for ISABELLE

Description: A dipole magnet, intended as a possible alternative for the ISABELLE main-ring magnet, was designed at LBL. Three layers of FNAL Doubler/Saver conductor were used. Two 1.3-m-long models were built and tested, both with and without an iron core, and in both helium I and helium II. The training behavior, cyclic energy loss, point of quench initiation, and quench velocity were determined. A central field of 6.5 tesla was obtained in He I (4.4 K), and 7.6 tesla in He II (1.8K).
Date: May 1, 1982
Creator: Taylor, C.; Althaus, R.; Caspi, S.; Gilbert, W.; Hassenzahl, W.; Meuser, R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phonon dispersion relation of uranium nitrate above and below the Neel temperature

Description: Neutron coherent inelastic scattering measurements have been made of the phonon dispersion relation of uranium nitride both above and below the Neel temperature T/sub N/ = 50 K. Within the precision of the measurements, about 1% in frequency and 10% in line width and in scattered neutron intensity, no significant changes in these phonon properties were observed as a function of temperature other than those arising from population factor changes and a small stiffening of the lattice as the tempe… more
Date: January 1, 1977
Creator: Dolling, G; Holden, T M; Evensson, E C; Buyers, W J.L. & Lander, G H
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An HVEM study of displacement cascade damage in Nb/sub 3/Sn at 13 K

Description: TEM images of the martensite structure in Nb/sub 3/Sn were recorded at various temperatures between 12 and 30/degree/K. The transition to the superconducting state was observed by a slight deflection of the electron beam due to a perturbation of the magnetic field of the objective lens at the sample. The primary interest is in irradiation effects due to fast neutrons from a fusion reactor, and therefore ion irradiation conditions that are somewhat comparable to this were selected. These consist… more
Date: February 1, 1988
Creator: Kirk, M. A.; Baker, M. C.; Kestel, B. J.; Weber, H. W. & Kampwirth, R. T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Operational history of Fermilab's 1500 W refrigerator used for energy saver magnet production testing

Description: The 1500 W helium refrigerator system utilizes two oil-injected screw compressors staged to feed a liquid nitrogen pre-cooled cold box. Refrigeration is provided by two Sulzer TGL-22 magnetic/gas bearing turbines. The refrigerator feeds six magnet test stands via a 10,000 L dewar and subcooler equipped distribution box. The design of the controls has permitted the system to be routinely operated 24 hours/day, seven days/week with only five operators. It has operated approximately 90% of the 4-1… more
Date: September 1, 1985
Creator: Bianchi, A. J.; Barger, R. K.; Johnson, F. B.; McGuire, K. J.; Pinyan, K. D.; Wilson, F. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Low temperature heat capacity of lutetium and lutetium hydrogen alloys

Description: The heat capacity of high purity electrotransport refined lutetium was measured between 1 and 20/sup 0/K. Results for theta/sub D/ were in excellent agreement with theta values determined from elastic constant measurements. The heat capacity of a series of lutetium-hydrogen solid solution alloys was determined and results showed an increase in ..gamma.. from 8.2 to about 11.3 mJ/g-atom-K/sup 2/ for hydrogen content increasing from zero to about one atomic percent. Above one percent hydrogen ..g… more
Date: October 1, 1977
Creator: Thome, D. K.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Thermodynamic Implications of Band Structure Effects for Rare Gases on Graphite

Description: Recent analyses of atomic beam scattering data have suggested that an anisotropic He-C pair interaction is appropriate to the problem of He on graphite. This results in considerably more corrugated equipotential surfaces than previously assumed, and correspondingly manifest band structure effects. These have been observed for He/graphite in the specific heat for temperature T > 3/sup 0/K. The implications for other gases and temperatures and for the effective adatom-adatom interaction are discu… more
Date: January 1, 1980
Creator: Carlos, W. E.; Cole, M. W.; Rauber, S.; Vidali, G.; Silva-Moreira, A. F.; Codona, J. L. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Survey of physical property data for several alloys. [Nitronic 33; copper C10400; copper C17510]

Description: This report summarizes an examination of physical property data available in the literature for six alloys of potential interest to the Toroidal Fusion Core Experiment in the Fusion Energy Program. The properties of thermal expansion, density, specific heat, electrical resistivity, and thermal conductivity were compiled for six alloys: Nitronic 33, a low-nickel, high manganese stainless steel; nickel-base Inconnel Alloys 625, 718, and X-750; and copper alloys C10400 and C17510. The temperatures… more
Date: August 1, 1985
Creator: Pawel, R. E. & Williams, R. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Air flow into the LBL Bevatron

Description: The Lawrence Berkeley Laboratory is currently installing an improved liner in its Bevatron. The new liner will be capable of producing a vacuum of 2 x 10/sup -8/ N/M/sup 2/ (1.5 x 10/sup -10/ Torr) and a temperature on the order of 12K. There has been concern for quite some time about possible damage to the liner in the event of a beam line window breaking allowing atmospheric air to rush into the vacuum. The installation of the new more fragile liner has heightened this concern. This effort is… more
Date: September 1, 1979
Creator: Williams, J.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the cryogenic mechanical properties of low thermal-expansion superalloys

Description: Four Fe-based superalloys, JBK-75, Incoloy 903, Incoloy 905, and Incoloy 909 were evaluated as tube materials for ICCS Nb/sub 3/Sn superconductors. Evaluation consisted of 4-K tensile and elastic-plastic fracture-toughness testing, and a microstructural characterization of unwelded and autogenously gas-tungsten-arc welded sheet given a simulated postweld processing treatment of 15% cold reduction by rolling followed by a Nb/sub 3/Sn-reaction heat treatment of 96 hours at 700/sup 0/C plus 48 hou… more
Date: July 30, 1985
Creator: Summers, L.T. & Dalder, E.N.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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NTD germanium: a novel material for low-temperature bolometers

Description: Six samples of ultra-pure (absolute value N/sub A/ - N/sub D/ absolute value less than or equal to 10/sup 11/cm/sup -3/), single-crystal germanium have been neutron transmutation doped with neutron doses between 7.5 x 10/sup 16/ and 1.88 x 10/sup 18/cm/sup -2/. After thermal annealing at 400/sup 0/C for six hours in a pure argon atmosphere, the samples have been characterized with Hall effect and resistivity measurements between 300 and 0.3 K. Our results show that the resistivity in the low te… more
Date: June 1, 1982
Creator: Haller, E. E.; Palaio, N. P.; Rodder, M.; Hansen, W. L. & Kreysa, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Intrinsically irreversible heat engines

Description: The concept of an intrinsically irreversible heat engine is examined as a means of obtaining temperatures near absolute zero. These engines use the irreversible process of thermal conduction to achieve the necessary phasing between temperature changes and motion of a primary medium and therefore have only one moving mechanical element. (GHT)
Date: January 1, 1982
Creator: Wheatley, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Austenitic stainless steels for cryogenic service

Description: Presently available information on austenitic Fe-Cr-Ni stainless steel plate, welds, and castings for service below 77 K are reviewed with the intent (1) of developing systematic relationships between mechanical properties, composition, microstructure, and processing, and (2) of assessing the adequacy of these data bases in the design, fabrication, and operation of engineering systems at 4 K.
Date: September 19, 1985
Creator: Dalder, E.N.C. & Juhas, M.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SSC Cryogenic System

Description: The design of the 4.5 K primary cooling system and higher temperature shield cooling systems for the SSC are described. Typical flow diagrams for the magnet piping systems are presented. Estimated heat loads are given. The systems have been designed to accomodate the great distances, 90 km and up, over which the load will be distributed. Provision has been made for cooldown, warmup, quench recovery and magnet replacement, as well as for steady-state operation.
Date: January 1, 1985
Creator: Brown, D. P.; Louttit, R. I.; Rode, C. & VanderArend, P. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pressurized helium II-cooled magnet test facility

Description: A facility for testing superconducting magnets in a pressurized bath of helium II has been constructed and operated. The cryostat accepts magnets up to 0.32 m diameter and 1.32 m length with current to 3000 A. In initial tests, the volume of helium II surrounding the superconducting magnet was 90 liters. Minimum temperature reached was 1.7 K at which point the pumping system was throttled to maintain steady temperature. Helium II reservoir temperatures were easily controlled as long as the temp… more
Date: June 1, 1980
Creator: Warren, R.P.; Lambertson, G.R.; Gilbert, W.S.; Meuser, R.B.; Caspi, S. & Schafer, R.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Zero-field. mu. SR and low-temperature. mu. /sup +/ diffusivity in copper

Description: In this paper the history of ..mu../sup +/ diffusion studies in copper, with particular emphasis on the increased low-temperature diffusivity which has been known for several years now, is reviewed. The theory and practice of the zero-field ..mu..SR method, which has come into increasing favor in the study of muon diffusion and trapping in metals, is surveyed, and its application to the low-temperature copper problem is discussed. 26 references.
Date: April 1, 1983
Creator: Clawson, C.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetization and critical currents of NbTi wires with fine filaments

Description: In high energy accelerators such as the SSC, the magnetization of the superconductor is an important component in determining the harmonic fields at injection (approx.0.3T). In an effort to reduce these residual fields, interest has focused on NbTi conductors with fine filaments which are expected to have a reduced magnetization as dictated by the critical state model. With this in view, the magnetization and critical currents were measured at 4.3K for a set of NbTi wires with filament diameter… more
Date: January 1, 1985
Creator: Ghosh, A.K. & Sampson, W.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of three 4. 5 m dipoles for SSC reference design D

Description: Three 4.5 m long dipoles for Reference Design D of the proposed Superconducting Super Collider have been successfully tested. The magnets are cold-iron (and cold bore) 1-in-1 dipoles, wound with current density-graded high homogeneity NbTi cable in a two-layer cos theta coil of 40 mm inner diameter. The coil is prestressed by 15 mm wide stainless steel collars, and mounted in a circular, split iron yoke of 267 mm outer diameter, supported in a cylindrical yoke containment vessel. At 4.5 K the m… more
Date: January 1, 1985
Creator: Dahl, P.; Cottingham, J.; Fernow, R.; Garber, M.; Ghosh, A.; Goodzeit, C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Mechanical characterization of selected adhesives and bulk materials at liquid nitrogen and room temperatures

Description: This paper presents the results of a series of mechanical tests on selected adhesives and bulk materials. The materials tested are of general interest to designers of magnets for cryogenic service and include several epoxies, a varnish, a B-stage glass cloth, insulation papers, and commercially available fiber-reinforced composites. These tests were performed at room temperature (293 K) and at liquid nitrogen temperature (77 K). The tests include both simple tension tests and lap shear tests wi… more
Date: January 1, 1977
Creator: Fitzpatrick, C.M. & Stoddart, W.C.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gravitational convection of subcooled He I and the transition into superfluid He II at atmospheric pressure

Description: The propagation velocity of the He II-He I interface at 1 atm was measured in a large experimental cryostat. During cooldown, He II at the lambda temperature propagates up and down in a gravitational field with an interface velocity V/sub b/ which depends on the He I temperature T/sub infinity/. For T/sub infinity/ = 4 K, V/sub b/ = 0.1 mm/sec and for T/sub infinity/ = 2.2 K, V/sub b/ = 2 mm/sec. During warm up, He I propagated with an interface velocity V/sub b/ > 30 mm/sec that was measured a… more
Date: June 1, 1980
Creator: Caspi, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Determination of very slow. mu. /sup +/ hop rates in Cu by LLF-. mu. SR

Description: Muon spin relaxation in low (weak) longitudinal magnetic field (LLF-..mu..SR) provides a means of independently determining the static dipolar width ..delta.. characterizing the ..mu../sup +/ lattice site and the correlation time tau/sub c/ for ..mu../sup +/ hopping, in a manner that is nearly model-independent for tau/sub c/ and especially accurate in the near-static limit (tau/sub c/ > tau/sub ..mu../). The advantages of this method are illustrated by its application to muon hopping in Cu nea… more
Date: January 1, 1986
Creator: Brewer, J. H.; Celio, M.; Harshman, D. R.; Keitel, R.; Kreitzman, S. R.; Luke, G. M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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