{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/29675"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/29675","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Radiation enhanced diffusion of neodymium in single crystal thin film UO2","abstract":"Radiation-enhanced diffusion (RED) of a Nd buried tracer layer in UO2 thin films was measured with Secondary Ion Mass Spectrometry (SIMS). Samples were irradiated with 1.8 MeV Kr+ over a temperature range from 400 to 800 C. RED in UO2 was found to be in the recombination limited regime. Dose rate dependence measurement showed radiation enhanced diffusivity was proportional to the square root of the irradiation flux, further demonstrating that the diffusion mechanism in the temperature range could be characterized by the recombination limited kinetics. Mixing parameter measurements indicated that ballistic mixing was the dominant mechanism of ion mixing. Thermal diffusion was also measured in the temperature range above. A very small yet observable diffusivity was measured at 800 C. A comparison of the diffusion properties between UO2 and CeO2 showed different behavior of the two materials, which indicated that the CeO2 system might not be a good surrogate for the UO2 system in terms of radiation enhanced diffusion.","abstract_html":"Radiation-enhanced diffusion (RED) of a Nd buried tracer layer in UO2 thin films was measured with Secondary Ion Mass Spectrometry (SIMS). Samples were irradiated with 1.8 MeV Kr+ over a temperature range from 400 to 800 C. RED in UO2 was found to be in the recombination limited regime. Dose rate dependence measurement showed radiation enhanced diffusivity was proportional to the square root of the irradiation flux, further demonstrating that the diffusion mechanism in the temperature range could be characterized by the recombination limited kinetics. Mixing parameter measurements indicated that ballistic mixing was the dominant mechanism of ion mixing. Thermal diffusion was also measured in the temperature range above. A very small yet observable diffusivity was measured at 800 C. A comparison of the diffusion properties between UO2 and CeO2 showed different behavior of the two materials, which indicated that the CeO2 system might not be a good surrogate for the UO2 system in terms of radiation enhanced diffusion.","abstract_has_math":false,"creators":["Han, Xiaochun"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Nuclear, Plasma, Radiolgc Engr","degree_department":null,"school":null,"contributors":["Heuser, Brent J."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012-02-06T20:10:23Z","date_published":"2012-02-06T20:10:23Z","updated_at":"2026-07-22T22:25:27Z","subjects":["Radiation-enhanced diffusion (RED)","UO2","recombination limited kinetics","ballistic mixing dominates."],"languages":["en"],"rights":["Copyright 2011 Xiaochun Han"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/29675","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Heuser, Brent J."]},{"key":"dc:creator","label":"Author","values":["Han, Xiaochun"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012-02-06T20:10:23Z","2011-12"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation / Thesis","text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Nuclear, Plasma, Radiolgc Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Radiation-enhanced diffusion (RED)","UO2","recombination limited kinetics","ballistic mixing dominates."]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2011 Xiaochun Han"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/29675"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Radiation-enhanced diffusion (RED) of a Nd buried tracer layer in UO2 thin films was measured with Secondary Ion Mass Spectrometry (SIMS). Samples were irradiated with 1.8 MeV Kr+ over a temperature range from 400 to 800 C. RED in UO2 was found to be in the recombination limited regime. Dose rate dependence measurement showed radiation enhanced diffusivity was proportional to the square root of the irradiation flux, further demonstrating that the diffusion mechanism in the temperature range could be characterized by the recombination limited kinetics. Mixing parameter measurements indicated that ballistic mixing was the dominant mechanism of ion mixing. Thermal diffusion was also measured in the temperature range above. A very small yet observable diffusivity was measured at 800 C. A comparison of the diffusion properties between UO2 and CeO2 showed different behavior of the two materials, which indicated that the CeO2 system might not be a good surrogate for the UO2 system in terms of radiation enhanced diffusion.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2011-12-08T16:21:12Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Han_Xiaochun.docx: 2943311 bytes, checksum: ad159c210d9a3803a0620e2d43e91a02 (MD5) Han_Xiaochun.pdf: 1215837 bytes, checksum: 473d643cba99191a0fdc20c3fe21ecdd (MD5)","Made available in DSpace on 2012-02-06T20:10:23Z (GMT). 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Dose rate dependence measurement showed radiation enhanced diffusivity was proportional to the square root of the irradiation flux, further demonstrating that the diffusion mechanism in the temperature range could be characterized by the recombination limited kinetics. Mixing parameter measurements indicated that ballistic mixing was the dominant mechanism of ion mixing. Thermal diffusion was also measured in the temperature range above. A very small yet observable diffusivity was measured at 800 C. A comparison of the diffusion properties between UO2 and CeO2 showed different behavior of the two materials, which indicated that the CeO2 system might not be a good surrogate for the UO2 system in terms of radiation enhanced diffusion.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2011-12-08T16:21:12Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Han_Xiaochun.docx: 2943311 bytes, checksum: ad159c210d9a3803a0620e2d43e91a02 (MD5) Han_Xiaochun.pdf: 1215837 bytes, checksum: 473d643cba99191a0fdc20c3fe21ecdd (MD5)","Made available in DSpace on 2012-02-06T20:10:23Z (GMT). No. of bitstreams: 3 Han_Xiaochun.pdf: 1215656 bytes, checksum: 8673e8a6c80a8046b33f01b28582bf7e (MD5) license.txt: 4059 bytes, checksum: 08489a1331af1e817bdee63cf36e8501 (MD5) Han_Xiaochun.docx: 2943311 bytes, checksum: ad159c210d9a3803a0620e2d43e91a02 (MD5)"],"dc:identifier":["http://hdl.handle.net/2142/29675"],"dc:language":["en"],"dc:rights":["Copyright 2011 Xiaochun Han"],"dc:subject":["Radiation-enhanced diffusion (RED)","UO2","recombination limited kinetics","ballistic mixing dominates."],"dc:title":["Radiation enhanced diffusion of neodymium in single crystal thin film UO2"],"dc:type":["Dissertation / Thesis","text"],"thesis:degree_discipline":["Nuclear, Plasma, Radiolgc Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:27Z"}