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Growth, preparation, and dielectric properties of monodomain single crystal PbTiO sub 3

Description: A method is described for obtaining monodomain PbTiO{sub 3} single crystals with high electrical resistivity (10{sup 10}{Omega} cm) and low dielectric frequency dispersion. The single crystals of PbTiO{sub 3} were grown by flux solution method. Space charge related defects, which result in the large dielectric frequency dispersion, were eliminated by heat treatments. 90{degrees} domains were removed by applying a unidirectional compressive stress along the <100> crystallographic direction. The … more
Date: May 1, 1992
Creator: Li, Z.; Xu, X. Z.; Dai, X. H.; Lam, D. J. & Chan, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical aspects of solid state reactions in a mixed particulate ensemble and kinetics of lead zirconate formation

Description: A theoretical analysis was carried out to estimate the quasi-steady-state external mass transport by lattice, surface and gaseous diffusion in terms of the stereologically measurable microstructural parameters of a mixed powder compact. It was shown that the gaseous transport can be described by a single dimensionless quantity termed sublimation transport modulus. Using these equations, the relative importance of the alternate external transport modes can be evaluated. Experimental work determi… more
Date: September 1, 1979
Creator: Chandratreya, S.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrodynamic/kinetic reactions in liquid-dominated geothermal systems. Final report

Description: A mobile geothermal well-site test unit at the Mercer 2 well in South Brawley, California (Imperial Valley), was constructed and tested. The equipment controlled, monitored, and recorded all process conditions of single- and dual-flash power cycles. Single- and two-phase flashed brine effluents were flowed through piping component test sections to provide hydrodynamic/kinetic data for scale formation. The unit operated at flowrates in excess of 200 gpm and is designed to accommodate flowrates u… more
Date: April 1, 1982
Creator: Nesewich, J.P. & Gracey, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Irreversibility behavior in Ag-sheathed Bi-based superconducting wires

Description: Irreversibility lines for Ag/(Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub y}(2223) wires prepared through a phase formation- decomposition-recovery (PFDR) process and normal annealing process were determined using both AC susceptibility measurements under DC fields and magnetisation measurements. It was found that flux pinning was enhanced in the PFDR processed samples over the normal processed samples, in particular at temperature above 77 K. The PFDR process results in high mass density, gr… more
Date: April 1, 1992
Creator: Dou, S.X.; Liu, H.K.; Guo, Y.C.; Wang, J.; Jin, X.J.; Hu, Q.Y. (New South Wales Univ., Kensington (Australia)) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Muon spin relaxation in CeCu/sub 2/Si/sub 2/ and muon Knight shift in various heavy-fermion systems

Description: Positive muon spin precession has been observed in varius heavy-fermion systems in the transverse external magnetic field. In the superconductor CeCu/sub 2.1/Si/sub 2/, the relaxation rate of muon spins increases rapidly with decreasing temperature below T/sub c/. This is interpreted as the results of the inhomogeneous fields due to the imperfect penetration of the external field into the type-II superconducting state. The magnetic-field penetration depth lambda is derived from the observed muo… more
Date: January 1, 1986
Creator: Uemura, Y. J.; Kossler, W. J.; Hitti, B.; Kempton, J. R.; Schone, H. E.; Yu, X. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Ferroelectric ceramics for dielectric power conversion. Annual report, March 1, 1979-April 30, 1980

Description: Materials selected for study were those which could be expected to have useful Curie temperatures, resistivities, coercive fields, and Devonshire coefficients. Materials studied include PZT (lead-zirconia-titania system), Bi(Na,K)Ti/sub 2/O/sub 6/, rare earth titanoniobates, other tantalates and niobates, and thin films. Graphs are given for spontaneous polarization as a function of composition, temperature dependence of spontaneous polarization and coercive field for modified PSZT dielectrics,… more
Date: May 1, 1980
Creator: Payne, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optical image storage in ion implanted PLZT ceramics

Description: Optical images can be stored in transparent lead-lanthanum-zirconate-titanate (PLZT) ceramics by exposure to near-uv light with photon energies greater than the band gas energy of approx. 3.35 eV. The image storage process relies on optically induced changes in the switching properties of ferroelectric domains (photoferroelectric effect). Stored images are nonvolatile but can be erased by uniform uv illumination and simultaneous application of an electric field. Although high quality images, wi… more
Date: January 1, 1980
Creator: Peercy, P. S. & Land, C. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of the sintering kinetics of lead powders. Final technical report

Description: An analysis of the parameters involved in the sintering of lead powders under vacuum has been made. Sintering was accomplished at temperatures between 250/sup 0/ and 280/sup 0/C. Evaluation of surface area reduction data results in values of the mechanism exponent N between 5.3 and 6.7. Lack of shrinkage and the low vapor pressure of lead at the experimental temperatures lead to the conclusion that surface diffusion is the rate-controlling sintering mechanism. However, comparison of the experim… more
Date: August 1, 1977
Creator: Higgins, P. K. & Munir, Z. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface treatment of lead glass microsphere

Description: The structural arrangement of a hydrated glass surface depends on the composition, thermal history and surface treatment. This paper considers the surface treatment of a lead glass with weak and strong acid solutions and in particular hydrogen peroxide, to give a microscopically clean microsphere.
Date: May 21, 1980
Creator: Andrews, J.E. Jr. & Koo, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermoelectric generator testing and RTG degradation-mechanisms evaluation. Progress report No. 32

Description: Thermal conductivity tests of the older p-type were terminated after 22,000 hours. The n-type selenide legs after 8000 hours continue to show agreement with the 3M Company published data. In the ingradient testing after 10,200 hours the n-legs show comparable performance to the reported 3M data. A new station for ingradient performance testing of the new design p-type legs with the Astroquartz/slurry wrap was nearly completed. Weight loss testing of the new design p-type TPM217 (no partition) w… more
Date: October 1, 1979
Creator: Lockwood, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary investigation of a technique to separate fission noble metals from fission product mixtures

Description: A variation of the gold-ore fire assay technique was examined as a method for recovering Pd, Rh and Ru from fission products. The mixture of fission product oxides is combined with glass-forming chemicals, a metal oxide such as PbO (scavenging agent), and a reducing agent such as charcoal. When this mixture is melted, a metal button is formed which extracts the noble metals. The remainder cools to form a glass for nuclear waste storage. Recovery depended only on reduction of the scavenger oxide… more
Date: August 1, 1982
Creator: Mellinger, G. B. & Jensen, G. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular mechanisms of the epithelial transport of toxic metal ions, particularly mercury, cadmium, lead, arsenic, zinc, and copper. Progress report, January 1, 1979-December 31, 1979. [Ca; Pb; cockerels]

Description: The mechanism of lead transport is presented, and especially the particular similarities or dissimilarities between lead and calcium in this process. The absorption of these metals was determined cockerels, raised on a commercial diet or on a specified diet, using in vivo ligated loop procedure. The dose administered into the loop contained 0.5 ..mu..Ci /sup 203/Pb (and/or 0.1 ..mu..Ci /sup 47/Ca), and 0.01 mM lead acetate (and/or mM CaCl/sub 2/) in 0.5 ml 0.15 M NaCl,pH 6.5. It was shown that … more
Date: January 1, 1979
Creator: Wasserman, R H
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multiply stripped ion generation in the metal vapor vacuum arc

Description: We consider the charge state distribution of ions produced in the metal vapor vacuum arc plasma discharge. A new kind of high current metal ion source in which the ion beam is extracted from a metal vapor vacuum arc plasma has been used to obtain the spectra of multiply charged ions produced within the cathode spots. The cathode materials used and the species reportetd on here are: C, Mg, Al, Si, Ti, Cr, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Rh, Pd, Ag, In, Sn, Gd, Ho, Ta, W, Pt, Au, Pb, Th, and U; t… more
Date: September 1, 1987
Creator: Brown, I.G.; Feinberg, B. & Galvin, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wavelength modulation spectroscopy of semiconductors

Description: The use of modulation spectroscopy to study the electronic properties of solids has been very productive. The construction of a wide range Wavelength Modulation Spectrometer to study the optical properties of solids is described in detail. Extensions of the working range of the spectrometer into the vacuum ultraviolet are discussed. Measurements of the reflectivity and derivative reflectivity spectra of the lead chalcogenides, the chalcopyrite ZnGeP/sub 2/, the layer compounds GaSe and GaS and … more
Date: October 1, 1977
Creator: Kohn, S.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A comprehensive review of the XRD data of the primary and secondary phases present in the BSCCO superconductor system

Description: X-ray powder patterns for the phases in the CaO-SrO-PbO ternary system, along with the corresponding crystal structures, were obtained from the literature and from the Powder Diffraction File (PDF). Available X-ray diffraction (XRD) patterns were compared with each other and, when possible, with a calculated pattern for each phase, yielding a recommended reference pattern. The simulated powder patterns presented here deal with the phases found within the (Ca,Sr){sub 2}PbO{sub 4} solid solution … more
Date: February 1, 1992
Creator: Reardon, B.J. & Hubbard, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The domain structure features of epitaxial PbTiO sub 3 thin films prepared by MOCVD

Description: Ferroelectric oxide thin films have attracted great interest in recent years because of their potential applications in numerous electro-optic, pyroelectric, acousto-optical, and nonvolatile memory devices, and a variety of methods such as sputtering, laser ablation, and MOCVD has been used for preparation of the films. Among these ferroelectric materials, the PbTiO{sub 3} thin film has been extensively studied because of its small dielectric constant, large spontaneous polarization, small coer… more
Date: March 1, 1992
Creator: Bai, G.R.; Chang, H.L.M.; Foster, C.M. & Lam, D.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of the dissolution of geothermal scale

Description: Samples of geothermal scale formed from Magmamax No. 1 and Woolsey No. 1 wells in the Imperial Valley, Calif., were exposed to concentrated and dilute solutions of common laboratory reagents. The time of exposure and temperature of the reagent were also varied. Several reagents easily dissolved significant amounts of the scale. An in situ test was performed with marginal success.
Date: February 4, 1980
Creator: Deutscher, S.B.; Ross, D.M.; Quong, R. & Harrar, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radioecology of Natural Systems. Final Report, May 1, 1962-October 31, 1979

Description: This is the final report to the US Department of Energy and its predecessors on Contract EY-76-S-02-1156 with Colorado State University. During the first five years of the program, investigations were focused on the accumulation of fallout radionuclides in a well-studied mule deer population in north-central Colorado. In 1967, the scope of the program was enlarged to include studies on radionuclide behavior in mountain lake ecosystems, radiation effects on a shortgrass plains ecosystem, and the… more
Date: October 31, 1979
Creator: Whicker, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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2006 Toxic Chemical Release Inventory Report for the Emergency Planning and Community Right-to-Know Act of 1986, Title III, Section 313

Description: For reporting year 2006, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead as required under the Emergency Planning and Community Right-to-Know Act (EPCRA) Section 313. No other EPCRA Section 313 chemicals were used in 2006 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2006, as well as to provide background inf… more
Date: December 12, 2007
Creator: Ecology and Air Quality Group & Hinojosa, Hector
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multipion production in nuclear collisions

Description: Two aspects of multipion production in nuclear collisions are discussed: the negative pion multiplicity distribution and the ..pi../sup -/..pi../sup -/ correlation function. The emphasis is on how these observables could be used to search for signals of collective phenomena in nuclear collisions. 2 figures.
Date: March 1, 1979
Creator: Gyulassy, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigations of the effect of the morphology of Nb dopant on lead zirconate ceramic

Description: The microstructures of ferroelectric ceramics are a result of the dopants and of the many process variables associated with raw materials, powder processing, and ceramic firing. Metal ion substitutions of higher than normal valency are used as sintering aids to promote densification, to increase electrical resistivity, and to develop mature homogeneous microstructures with desirable piezoelectric and ferroelectric properties. Investigations are reported for the barium modified lead zirconate sy… more
Date: January 1, 1979
Creator: Keck, J. D. & Wilcox, P. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Program of thermoelectric generator testing and RTG degradation mechanisms evaluation. Progress report No. 38

Description: The n-type gadolinium selenide legs after 17,500 hours continue to show reasonable agreement with the 3M Co. published thermal conductivity data. Weight loss for both coated and uncoated Si-Ge material produced by G.E. are reported. No significant discrepancies with the results previously obtained on R.C.A. material from the MHW program have been found. Thermal conductivity measurements are also in agreement. The remaining MHW generator on test, Q1-A, has accumulated 26,800 hours and performanc… more
Date: November 1, 1980
Creator: Lockwood, A. & Shields, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Large acceptance spectrometers for. pi. /sup 0/ mesons. [Produced in heavy ion reactions]

Description: A spectrometer composed of lead-oxide loaded glass blocks has been constructed for detection of neutral pi mesons emitted in low energy heavy ion reactions. The spectrometer detects the Cerenkov radiation emitted when the high energy photons (E..gamma.. approx. 70 MeV) resulting from ..pi../sup 0/ decay create electron-position pairs in the glass, initiating electromagnetic showers. A geometric acceptance of better than 5% of 4..pi.. is possible; the ..pi../sup 0/ detection efficiency varies be… more
Date: January 1, 1984
Creator: Awes, T. C.; Ferguson, R. L.; Obenshain, F. E.; Plasil, F.; Young, G. R.; Braun-Munzinger, P. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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