{"id":{"repo_id":"must-thes","oai_identifier":"oai:scholarsmine.mst.edu:doctoral_dissertations-2869"},"canonical_url":"https://search.dev.ndltd.org/etd/must-thes/oai:scholarsmine.mst.edu:doctoral_dissertations-2869","repository":{"repo_id":"must-thes","name":"Missouri University of Science and Technology","base_url":"https://scholarsmine.mst.edu/do/oai/"},"display":{"title":"Internal friction of mixed-alkali silicate glasses","abstract":"\"The mixed alkali effect in silicate glasses was examined from internal friction measurements made over the temperature range from -190 to 500⁰C and at a frequency of 0.4 Hz. Supplemental measurements of the activation energy for the different internal friction peaks, dynamic shear modulus, density, and index of refraction were also made. All measurements were confined to silicate glasses containing mixtures of Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, and K-Rb. Rötger's interpretation of the internal friction of mixed-alkali silicate glasses is shown to be incorrect. A previously unreported internal friction peak was observed whenever two different alkali oxides were present simultaneously, The behavior of this peak in the different mixed alkali glasses is more easily correlated with the radius ratio of the two alkali ions present than with the mass ratio. A stress induced alkali ion position interchange is suggested as the probable mechanism responsible for this peak\"--Abstract, page ii.","abstract_html":""The mixed alkali effect in silicate glasses was examined from internal friction measurements made over the temperature range from -190 to 500⁰C and at a frequency of 0.4 Hz. Supplemental measurements of the activation energy for the different internal friction peaks, dynamic shear modulus, density, and index of refraction were also made. All measurements were confined to silicate glasses containing mixtures of Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, and K-Rb. Rötger's interpretation of the internal friction of mixed-alkali silicate glasses is shown to be incorrect. A previously unreported internal friction peak was observed whenever two different alkali oxides were present simultaneously, The behavior of this peak in the different mixed alkali glasses is more easily correlated with the radius ratio of the two alkali ions present than with the mass ratio. A stress induced alkali ion position interchange is suggested as the probable mechanism responsible for this peak"--Abstract, page ii.","abstract_has_math":false,"creators":["Shelby, James E."],"institution":"University of Missouri at Rolla","degree_name":"Ph. D. in Ceramic Engineering","degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-02-10T08:00:00Z","date_published":"2016-02-10T08:00:00Z","updated_at":"2026-07-24T03:19:21Z","subjects":["Ceramic Materials"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsmine.mst.edu/doctoral_dissertations/1867","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Shelby, James E."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2016-02-10T08:00:00Z"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation - Open Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph. D. in Ceramic Engineering"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Missouri at Rolla"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Ceramic Materials"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsmine.mst.edu/doctoral_dissertations/1867"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["\"The mixed alkali effect in silicate glasses was examined from internal friction measurements made over the temperature range from -190 to 500⁰C and at a frequency of 0.4 Hz. Supplemental measurements of the activation energy for the different internal friction peaks, dynamic shear modulus, density, and index of refraction were also made. All measurements were confined to silicate glasses containing mixtures of Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, and K-Rb. Rötger's interpretation of the internal friction of mixed-alkali silicate glasses is shown to be incorrect. A previously unreported internal friction peak was observed whenever two different alkali oxides were present simultaneously, The behavior of this peak in the different mixed alkali glasses is more easily correlated with the radius ratio of the two alkali ions present than with the mass ratio. A stress induced alkali ion position interchange is suggested as the probable mechanism responsible for this peak\"--Abstract, page ii."]},{"key":"dc:title","label":"Title","values":["Internal friction of mixed-alkali silicate glasses"]}]}],"canonical_facts":{"dc:creator":["Shelby, James E."],"dc:date.available":["2016-02-10T08:00:00Z"],"dc:description.abstract":["\"The mixed alkali effect in silicate glasses was examined from internal friction measurements made over the temperature range from -190 to 500⁰C and at a frequency of 0.4 Hz. Supplemental measurements of the activation energy for the different internal friction peaks, dynamic shear modulus, density, and index of refraction were also made. All measurements were confined to silicate glasses containing mixtures of Li-Na, Li-K, Li-Rb, Li-Cs, Na-K, Na-Rb, Na-Cs, and K-Rb. Rötger's interpretation of the internal friction of mixed-alkali silicate glasses is shown to be incorrect. A previously unreported internal friction peak was observed whenever two different alkali oxides were present simultaneously, The behavior of this peak in the different mixed alkali glasses is more easily correlated with the radius ratio of the two alkali ions present than with the mass ratio. A stress induced alkali ion position interchange is suggested as the probable mechanism responsible for this peak\"--Abstract, page ii."],"dc:identifier":["https://scholarsmine.mst.edu/doctoral_dissertations/1867"],"dc:subject":["Ceramic Materials"],"dc:title":["Internal friction of mixed-alkali silicate glasses"],"dc:type":["Dissertation - Open Access"],"thesis:degree_name":["Ph. D. in Ceramic Engineering"],"thesis:institution_name":["University of Missouri at Rolla"]},"updated_at":"2026-07-24T03:19:21Z"}