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Density and Thermal Expansion of Ethyl Alcohol and of its Mixtures with Water

Description: Report issued by the Bureau of Standards over the thermal expansion of ethyl alcohol. As stated in the introduction, "the scope of the present work includes the preparation of pure anhydrous ethyl alcohol, the determination of the density and thermal expansion of this alcohol and its mixtures with water, and the construction from these data of tables for convenient use" (p. 328). This report includes tables, and illustrations.
Date: 1913
Creator: Osborne, N. S.; McKelvy, E. C. & Bearce, H. W.
Partner: UNT Libraries Government Documents Department

Thermal relations for two-phase expansion with phase equilibrium and example for combustion products of boron-containing fuel

Description: Report presenting a procedure for integrating equations involving pressure, temperature, and density in order to analyze an expansion process that occurs when boric oxide from fuels condenses during expansion. An example is provided to illustrate the manner in which the equations can be used to analyze a one-dimensional expansion with phase equilibrium.
Date: May 20, 1957
Creator: Tower, Leonard K.
Partner: UNT Libraries Government Documents Department

A New Interferential Dilatometer

Description: Scientific paper issued by the Bureau of Mines over development of a dilatometer. The instrument is used in tests of thermal expansion. The methods are presented and discussed. This paper includes an illustration.
Date: February 28, 1920
Creator: Priest, Irwin G.
Partner: UNT Libraries Government Documents Department

Frequency dependent thermal expansion in binary viscoelasticcomposites

Description: The effective thermal expansion coefficient beta* of abinary viscoelastic composite is shown to be frequency dependent even ifthe thermal expansion coefficients beta A and beta B of both constituentsare themselves frequency independent. Exact calculations for binaryviscoelastic systems show that beta* is related to constituent valuesbeta A, beta B, volume fractions, and bulk moduli KA, KB, as well as tothe overall bulk modulus K* of the composite system. Then, beta* isdetermined for isotropic systems by first bounding (or measuring) K* andtherefore beta*. For anisotropic systems with hexagonal symmetry, theprincipal values of the thermal expansion beta*perp and beta*para can bedetermined exactly when the constituents form a layered system. In allthe examples studied, it is shown explicitly that the eigenvectors of thethermoviscoelastic system possess non-negative dissipation -- despite thecomplicated analytical behavior of the frequency dependent thermalexpansivities themselves. Methods presented have a variety ofapplications from fluid-fluid mixtures to fluid-solid suspensions, andfrom fluid-saturated porous media to viscoelastic solid-solidcomposites.
Date: December 1, 2007
Creator: Berryman, James G.
Partner: UNT Libraries Government Documents Department

Computer-operated quartz differential dilatometer

Description: From international symposium on thermal expansion of solids; Lake of the Czarks, Missouri, USA (7 Nov 1973). A quartz differential dilatometer was interfaced with a Digital Equipment Corporation PDP-8 computer to automatically measure the thermal expansion of solids from 300 to 1000 K. A Carson-Dice Electronic-Mechanicai Micrometer, readable to 2.5 x 10/sup -6/ cm, was employed for length-change measurements accurate to 2.5 x 10/sup -5/ cm. Calibrated Pt/Pt/ sub 90/Rh/sub 10/ thermocouples were used to measure temperature changes to plus or minus 0.22 K. The software and hardware necessary to completely automate the measurements are described. Measurements on National Bureau of Standards certified quartz, tungsten, and copper specimens demonstrated an accuracy of plus or minus 1.5% in determination of the coefficient of thermal expansion. (auth)
Date: January 1, 1973
Creator: Kollie, T.G.; McElroy, D.L.; Hutton, J.T. & Ewing, W.M.
Partner: UNT Libraries Government Documents Department

Low-energy electron diffraction study of the thermal expansion of Ag(111)

Description: The temperature dependence of the first three interlayer distances of the Ag(111) surface was studied by low-energy electron diffraction (LEED) over the temperature range 128K to 723 K. The first three interlayer spacings and the effective Debye temperatures were extracted from the LEED analysis. At the lowest temperature, the first two interlayer spacings are slightly (0.5 percent) contracted. All three interlayer spacings increase with temperature, finally reaching expansions relative to the bulk of about 0.8 percent at the highest temperature studied. The effective surface Debye temperature is lowest for the outermost layer, increasing toward the bulk value for successive layers.
Date: May 19, 2000
Creator: Soares, E.A.; Leatherman, G.S.; Diehl, R.D. & Van Hove, M.A.
Partner: UNT Libraries Government Documents Department

Comparison between structural properties of bulk GaN grown under high N pressure and GaN grown by other methods

Description: In this paper defects formed in GaN grown by different methods are reviewed. Formation of particular defects are often related to the crystallographic direction in which the crystals grow. For bulk crystals the highest growth rates are observed for directions perpendicular to the c-axis. Threading dislocations and nanopipes along the c-axis are not formed in these crystals, but polarity of the growth direction plays a role concerning defects that are formed and surface roughness. For growth of homoepitaxial layers, where growth is forced to take place in the c-direction threading dislocations are formed and their density is related to the purity of constituents used for growth and to substrate surface inhomogeneities. In heteroepitaxial layers two other factors: lattice mismatch and thermal expansion mismatch are related to the formation of dislocations. Doping of crystals can also lead to formation of defects characteristic for a specific dopant. This type of defects tends to be growth method independent but can depend on growth polarity.
Date: July 31, 2002
Creator: Liliental-Weber, Z.; Jasinski, J. & Washburn, J.
Partner: UNT Libraries Government Documents Department

Why cryogenically cooled, thin crystals handle extremely high power densities

Description: Recently, a new type of cryogenically cooled high heat load monochromator was proposed and, developed at Argonne National Laboratory and tested at European Synchrotron Radiation Facility (ESRF.) These tests showed that powers of 153 W and power densities of 450 W/mm{sup 2} cause only negligible strain. These powers and power densities are larger than will be absorbed by the first crystal on an undulator beamline at the Advanced Photon Source (APS). In our earlier work we suggested that the crystal might show strain at much lower values of the powers and power densities. We now can explain the ESRF results in terms of the unique role the negative thermal expansion coefficient of Si plays in minimizing strain.
Date: September 1, 1995
Creator: Knapp, G.S.; Jennings, G. & Beno, M.A.
Partner: UNT Libraries Government Documents Department

Thermal Expansion of Insulating Materials

Description: Scientific paper issued by the Bureau of Standards over studies on thermal expansion. Expansivity tests are conducted on many different insulating materials. The results of the tests are discussed. This paper includes tables, photographs, and illustrations.
Date: December 27, 1919
Creator: Souder, Wilmer H. & Hidnert, Peter
Partner: UNT Libraries Government Documents Department

Measurements on the Thermal Expansion of Fused Silica

Description: Scientific paper issued by the Bureau of Standards over thermal expansion of fused silica. As stated in the abstract, "this paper gives the results of an investigation on the thermal expansion of transparent and nontransparent fused silica for various temperature ranges between -125 and +1,000 degrees Celsius. A detailed description of the apparatus and the methods used in this research and a summary of available data obtained by previous observers on the thermal expansion of fused silica are given" (p. 1). This paper includes tables, photographs, and illustrations.
Date: April 13, 1926
Creator: Souder, Wilmer H. & Hidnert, Peter
Partner: UNT Libraries Government Documents Department

Density of metallic polonium

Description: Determinations of the density and coefficient of thermal expansions of postum (Polonium 210) were attempted on 20 curies of polonium as obtained from production foils.
Date: May 18, 1948
Creator: Brody, B.
Partner: UNT Libraries Government Documents Department

The Thermal Expansion of NaCl at High Pressures and Temperatures

Description: Abstract: The thermal expansion of NaCl at high pressures and temperatures is estimated by extrapolating high temperature compressibility data to high pressures using finite strain theory. The thermal expansion is apparently negative at pressures over 50,000 bars at 300°C and at higher pressures at other temperatures.
Date: December 1958
Creator: Hughes, Harry
Partner: UNT Libraries Government Documents Department

High temperature materials engineering properties evaluation (Task 57017). Summary report

Description: Declassified 21 Sep 1973. The following were studied: mechanical properties of WUO/sub 2/ -- ThO/sub 2/, Mo --54UO/sub 2/ --6ThO/sub 2/. W--3Re -- 54UO/sub 2/ -6ThO/sub 2/, Mo--50Re, W--30Re--3OMo, Ta and Ta --8W--2Hf; thermal expansion of W-25Re--30Mo and unclad and Ta-clad W--54UO/sub 2/--6ThO/sub 2/; and electric conductivity of Ta tubing and Ta-clad W--54UO/sub 2/-6ThO/sub 2/. (DLC)
Date: August 18, 1967
Creator: Conway, J.B. & McCullough, W.L.
Partner: UNT Libraries Government Documents Department

Development of low coefficient of thermal expansion (CTE) nickel alloys for potential use as interconnects in SOFC

Description: This paper deals with the development of low coefficient of thermal expansion (CTE) nickel-base superalloys for potential use as interconnects for SOFC. Ni-Mo-Cr alloys were formulated with CTE on the order of 12.5 to 13.5 x10-6/°C. The alloys were vacuum induction melted and reduced to sheet via a combination of hot and cold working. Dilatometry was used to measure CTE of the alloys. Oxidation behavior of the alloys at 800°C in dry and moist air is reported. The results are compared to results for Haynes 230 (a commercial Ni-base superalloy) and for Crofer 22APU (a commercial ferritic stainless steel designed specifically for use as an SOFC interconnect).
Date: November 1, 2004
Creator: Alman, David E. & Jablonski, Paul D.
Partner: UNT Libraries Government Documents Department

Thermophysical Properties of U-10MO Alloy

Description: This report provides an overview of thermophysical properties of unirradiated uranium alloyed with ten weight percent molybdenum (U 10Mo), with particular focus on those material properties needed for modeling of new fuels for HPRRs (High Performance Research Reactors). The report contains both historical data available in the literature on U-10Mo, as well as more recent results conducted by the Global Threat Reduction Initiative fuel development program. The main use of the report is intended as a standard U-10Mo alloy properties reference for reactor models and simulations.
Date: November 1, 2010
Creator: Phillips, A. M.; Mickum, G. S. & Burkes, D. E.
Partner: UNT Libraries Government Documents Department

HAZARDS OF THERMAL EXPANSION FOR RADIOLOGICAL CONTAINER ENGULFED IN FIRE

Description: Fire accidents pose a serious threat to nuclear facilities. It is imperative that transport casks or shielded containers designed to transport/contain radiological materials have the ability to withstand a hypothetical fire. A numerical simulation was performed for a shielded container constructed of stainless steel and lead engulfed in a hypothetical fire as outlined by 10 CFR §71.73. The purpose of this analysis was to determine the thermal response of the container during and after the fire. The thermal model shows that after 30 minutes of fire, the stainless steel will maintain its integrity and not melt. However, the lead shielding will melt since its temperature exceeds the melting point. Due to the method of construction of the container under consideration, ample void space must be provided to allow for thermal expansion of the lead upon heating and melting, so as to not overstress the weldment.
Date: May 1, 2013
Creator: Guillen, Donna Post
Partner: UNT Libraries Government Documents Department

Bioactive glass coatings for orthopedic metallic implants

Description: The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.
Date: June 30, 2003
Creator: Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki & Tomsia, Antoni P.
Partner: UNT Libraries Government Documents Department