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- Borates -- Research<br />Silver compounds -- Effect of temperature on<br />Glass -- Heat treatment<br />Borates -- Spectra<br />Internal friction -- Measurement (1)
- Ceramic materials -- Mechanical properties<br />Sintering<br />Magnesium oxide<br />Chromium (1)
- Cesium compounds -- Analysis<br />Chemical equilibrium<br />Phase rule and equilibrium<br />Thermal conductivity -- Measurement (1)
- Glass fibers -- Analysis<br />Ceramic materials -- Microstructure<br />Internal friction -- Measurement (1)
- Glass-ceramics<br />Internal friction -- Measurement<br />Silicates<br />Alkalies (1)
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- Materials -- Density -- Measurement<br />Stoichiometry<br />Cadmium compounds -- Effect of high temperatures on<br />Pycnometer (1)
- Mullite -- Creep -- Mathematical models<br />Mullite -- Effect of temperature on<br />Materials at high temperatures (1)
- Surfaces (Technology) -- Analysis<br />Tungsten<br />Boron<br />Adsorption (1)
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Articles 1 - 12 of 12
Full-Text Articles in Engineering
Structure And Properties Of Silver Borate Glasses, E. N. Boulos, N. J. Kreidl
Structure And Properties Of Silver Borate Glasses, E. N. Boulos, N. J. Kreidl
Materials Science and Engineering Faculty Research & Creative Works
Clear glasses form in the system Ag2O‐B2O3 up to about 35 mol% (65 wt%) Ag2O. Infrared absorption, thermal expansion, and density data indicated an analogy to the Na2O‐B2O3 system. Pentaborate‐triborate group pairs appear to be formed on addition of Ag2O to B2O3 up to 20 mol% Ag2O and diborate groups from 20 to 33 mol% Ag2O. This interpretation is supported by the comparison of the infrared absorption spectra of quenched and crystallized glasses. One crystallization product, Ag2O‐4B2O3, was …
Final Sintering Of Cr₂O₃ With Minor Additions Of Mgo And Sintering Of Mgo With Minor Additions Of Cr₂O₃, Gordon E. Jungquist
Final Sintering Of Cr₂O₃ With Minor Additions Of Mgo And Sintering Of Mgo With Minor Additions Of Cr₂O₃, Gordon E. Jungquist
Masters Theses
"The effect of oxygen activity on the sintering of Cr₂O₃ with minor additions of MgO, and of MgO with minor additions of Cr₂O₃ at 1600ºC was investigated. A peak density (99.4% of theoretical) was obtained for high purity Cr₂O₃ by maintaining the equilibrium oxygen partial pressure needed to maintain the Cr₂O₃ phase. The addition of 0.1 wt. % MgO increased the sintered density at the same oxygen pressure to 99.8%. Further MgO additions decreased the density. The density of pure MgO was independent of the PO₂ over the range investigated. Addition of Cr₂O₃ to MgO decreased the density at …
Thermal Expansion Of Pb3o4, Charles A. Sorrell
Thermal Expansion Of Pb3o4, Charles A. Sorrell
Materials Science and Engineering Faculty Research & Creative Works
Thermal expansion of Pb3O4 was investigated by high‐temperature X‐ray diffraction. The coefficient in the a0 direction is 14.6x10−6/°C. Expansion in the c0 direction is 32% greater, with a coefficient of 19.3x10−6/°C. Coefficients of expansion are linear from 25° to 490°C and are comparable with those of tetragonal and orthorhombic PbO. Copyright © 1971, Wiley Blackwell. All rights reserved
Liquid Viscosity Measurement Using A Buret: An Instructional Technique, Charles A. Sorrell
Liquid Viscosity Measurement Using A Buret: An Instructional Technique, Charles A. Sorrell
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Structure And Properties Of Silver Borate Glasses, Edward Nashed Boulos
Structure And Properties Of Silver Borate Glasses, Edward Nashed Boulos
Doctoral Dissertations
"Clear glasses form in the system Ag₂O-B₂O₃ up to about 35 mol.% (65 wt.%) Ag₂O. Infrared absorption, thermal expansion and density data indicated an analogy to the Na₂O-B₂O₃ system. Pentaborate-triborate group pairs appear to be formed upon the addition of Ag₂O to B₂O₃ up to 20 mol.% Ag₂O and diborate groups from 20 to 33 mol.% Ag₂O. This interpretation is supported by the comparison of the infrared absorption spectra of quenched and crystallized glasses. One crystallization product ,Ag₂O.4B₂O₃, has been identified previously. A new compound starts to appear at 28 mol.% Ag₂O. Silver is generally present as a network modifier …
Evaluation Of A Cation Isotopic Substitution Technique In Conjunction With A High Temperature Gas Pycnometer For Determining The Stoichiometry Of Materials, Michael Clair Graves
Evaluation Of A Cation Isotopic Substitution Technique In Conjunction With A High Temperature Gas Pycnometer For Determining The Stoichiometry Of Materials, Michael Clair Graves
Masters Theses
"This study was concerned with the evaluation of a high temperature gas pycnometer, used in conjunction with a cation isotopic substitution technique, for determining the stoichiometry of materials. Three methods were investigated for determining the correction factors for the thermal gradient effects in the gas pycnometer. The correction factors were shown to be dependent on the temperature, the sample volume, and the height of the sample in the sample chamber. Under the conditions of these experiments, the correction factors were shown to be essentially independent of sample grain size and pycnometer atmosphere. The determination of the stoichiometry of cadmium oxide …
Mixed‐Cation Effect In Silver Borate Glasses, E. N. Boulos, N. J. Kreidl
Mixed‐Cation Effect In Silver Borate Glasses, E. N. Boulos, N. J. Kreidl
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Internal Friction Of Ion Exchanged Li₂O•Al₂O₃•2sio₂ Glasses, A. Ismail A. Abdel-Latif
Internal Friction Of Ion Exchanged Li₂O•Al₂O₃•2sio₂ Glasses, A. Ismail A. Abdel-Latif
Doctoral Dissertations
"Li₂O•Al₂O₂•2SiO₂ glass fibers were ion-exchanged from 1 to 300 minutes in a sodium nitrate bath at 366ºC. The internal friction was measured along with the lithium and sodium concentration profiles. As sodium progressively replaced lithium, the alkali internal friction peak became smaller while a new peak (mixed alkali peak) appeared and increased in magnitude. These changes in the internal friction are similar to those that occur upon the addition of a second alkali to glasses prepared by conventional melting. The magnitude of both internal friction peaks in ion exchanged glasses was dependent on the overall glass composition. The magnitude of …
Surface Reactions Of Boron With Clean Tungsten Substrates, Thomas A. Flaim
Surface Reactions Of Boron With Clean Tungsten Substrates, Thomas A. Flaim
Doctoral Dissertations
"A model developed to predict adsorbate-induced work-function changes for thermionic emitters is shown here to apply to a more general class of electron emission phenomena and a much broader range of adsorbates. This model predicts that chemically, vapor-deposited boron will increase the work function of a clean tungsten substrate at coverages between 0 and 1 monolayer. This is the first time that a single model has been shown to predict both positive and negative work function changes for different adsorbates. The reactions of chemically, vapor-deposited (CVD) boron with clean tungsten substrates were studied using field emission microscopy (FEM) and low …
High Temperature Compressive Creep In Mullite, Peter C. Smith
High Temperature Compressive Creep In Mullite, Peter C. Smith
Masters Theses
"Compressive creep measurements were made on two groups of mullites at temperatures between 1455ºC and 1520ºC. The first group consisted of commercially manufactured mullites. The second group was made up of 7 different mullite compositions spanning the alumina-silica solid solution range from 3Al₂O₃ • 2SiO₂ to 2Al₂O₃ • SiO₂ . Thermal activation energies and stress exponents were calculated for the mullites in the second group. Steady state strain rates taken at 1460ºC under loads of 100 and 110 psi varied between 1.3x10⁻⁴ in/in/hr and 15.4x10⁻⁴ in/in/hr. Activation energies were between 109 Kcal/mole and 204 Kcal/mole. Stress exponents calculated from data …
The Pm3m-Fm3m Transformation And Phase Equilibrium In Solid Solutions Of Csc1 With Kc1, Rbc1, And Csbr, John David Weyand
The Pm3m-Fm3m Transformation And Phase Equilibrium In Solid Solutions Of Csc1 With Kc1, Rbc1, And Csbr, John David Weyand
Masters Theses
"Thermal expansion and the Pm3m t Fm3m transition of cesium chloride have been studied with high temperature diffractometry, differential thermal analysis, and heating and quenching techniques. The onset temperature of the transition in pure CsCl, on heating, is 471ºC. There are no observable premonitory effects below the transition temperature and no apparent structural relationships between the polymorphs is apparent. Both phases coexist over a 20º to 50ºC temperature range and equilibrium thermal hysteresis occurs on heating and cooling. Hysteresis behavior is explained by addition of strain energy parameters to the free energy function. Initiation of the Pm3m t Fm3m transformation …
Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr.
Alkali Mobility And Mechanical Relaxation In Mixed-Alkali Silicate Glasses, James W. Fleming Jr.
Masters Theses
"Internal friction and sodium and potassium self-diffusion coefficients for (1-X)Na₂O · XK₂O· 3SiO₂ glasses were measured. Alkali diffusion was measured between 300 and 500ºC using radioactive isotopes and a thin-sectioning technique. Internal friction was measured from room temperature to 500ºC, 0.1 to 2000 Hz. Comparison between alkali diffusion and internal friction data for Na-K glasses with those for other mixed-alkali glasses shows that the mixed-alkali peak is related to alkali mobility. It is concluded that the mechanism for mixed-alkali internal friction is a cooperative rearrangement of dissimilar alkali ions, with the slower moving ion controlling the rate of reorientation"--Abstract, page …