{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/70093"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/70093","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Chemical and Chromatographic Studies on Dimeric Fatty Acids (Heated Fats)","abstract":"Dimer acids, representative of those from thermal-oxidative reactions in fats and oils, differing in polarity and structure and including the thermal, dehydro and bicyclic dimers of methyl linoleate, the dehydrodimer of methyl oleate, the tetrahydroxy and dihydroxy dimers of methyl stearate and the diketo dimer of methyl stearate were synthesized, purified and chemically characterized by the use of mass spectrometry, spectroscopy and chemical analysis. Effective chromatographic systems including gel permeation chromatography, high performance size exclusion chromatography, gas liquid chromatography, high performance liquid chromatography and thin layer chromatography were developed in order to identify and isolate dimer present in an oxidation mixture (GPC, HPSEC, GLC, TLC) as well as to separate dimeric mixtures according to polarity (packed and capillary GLC, reverse and normal HPLC) and into their isomeric components (capillary GLC). Furthermore, dimeric acids from two differently oxidized oil samples were isolated, structurally characterized and the mechanism of their formation explained.","abstract_html":"Dimer acids, representative of those from thermal-oxidative reactions in fats and oils, differing in polarity and structure and including the thermal, dehydro and bicyclic dimers of methyl linoleate, the dehydrodimer of methyl oleate, the tetrahydroxy and dihydroxy dimers of methyl stearate and the diketo dimer of methyl stearate were synthesized, purified and chemically characterized by the use of mass spectrometry, spectroscopy and chemical analysis. Effective chromatographic systems including gel permeation chromatography, high performance size exclusion chromatography, gas liquid chromatography, high performance liquid chromatography and thin layer chromatography were developed in order to identify and isolate dimer present in an oxidation mixture (GPC, HPSEC, GLC, TLC) as well as to separate dimeric mixtures according to polarity (packed and capillary GLC, reverse and normal HPLC) and into their isomeric components (capillary GLC). Furthermore, dimeric acids from two differently oxidized oil samples were isolated, structurally characterized and the mechanism of their formation explained.","abstract_has_math":false,"creators":["Christopoulou, Constantina Nicholaos"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Food Science","degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014-12-15T21:10:12Z","date_published":"2014-12-15T21:10:12Z","updated_at":"2026-07-22T22:26:02Z","subjects":["Agriculture, Food Science and Technology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["(UMI)AAI8701463"],"render_values":[{"text":"(UMI)AAI8701463","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/70093","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Christopoulou, Constantina Nicholaos"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2014-12-15T21:10:12Z","10000-01-01","1986"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Food Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"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":["Agriculture, Food Science and Technology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/70093","(UMI)AAI8701463"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Dimer acids, representative of those from thermal-oxidative reactions in fats and oils, differing in polarity and structure and including the thermal, dehydro and bicyclic dimers of methyl linoleate, the dehydrodimer of methyl oleate, the tetrahydroxy and dihydroxy dimers of methyl stearate and the diketo dimer of methyl stearate were synthesized, purified and chemically characterized by the use of mass spectrometry, spectroscopy and chemical analysis. Effective chromatographic systems including gel permeation chromatography, high performance size exclusion chromatography, gas liquid chromatography, high performance liquid chromatography and thin layer chromatography were developed in order to identify and isolate dimer present in an oxidation mixture (GPC, HPSEC, GLC, TLC) as well as to separate dimeric mixtures according to polarity (packed and capillary GLC, reverse and normal HPLC) and into their isomeric components (capillary GLC). Furthermore, dimeric acids from two differently oxidized oil samples were isolated, structurally characterized and the mechanism of their formation explained.","Made available in DSpace on 2014-12-15T21:10:12Z (GMT). No. of bitstreams: 1 8701463.pdf: 5943652 bytes, checksum: 0189d30faaf25814cad180a92cc1cce0 (MD5) Previous issue date: 1986","Embargo set by: Seth Robbins for item 70259 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","217 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986."]},{"key":"dc:title","label":"Title","values":["Chemical and Chromatographic Studies on Dimeric Fatty Acids (Heated Fats)"]}]}],"canonical_facts":{"dc:creator":["Christopoulou, Constantina Nicholaos"],"dc:date":["2014-12-15T21:10:12Z","10000-01-01","1986"],"dc:description":["Dimer acids, representative of those from thermal-oxidative reactions in fats and oils, differing in polarity and structure and including the thermal, dehydro and bicyclic dimers of methyl linoleate, the dehydrodimer of methyl oleate, the tetrahydroxy and dihydroxy dimers of methyl stearate and the diketo dimer of methyl stearate were synthesized, purified and chemically characterized by the use of mass spectrometry, spectroscopy and chemical analysis. Effective chromatographic systems including gel permeation chromatography, high performance size exclusion chromatography, gas liquid chromatography, high performance liquid chromatography and thin layer chromatography were developed in order to identify and isolate dimer present in an oxidation mixture (GPC, HPSEC, GLC, TLC) as well as to separate dimeric mixtures according to polarity (packed and capillary GLC, reverse and normal HPLC) and into their isomeric components (capillary GLC). Furthermore, dimeric acids from two differently oxidized oil samples were isolated, structurally characterized and the mechanism of their formation explained.","Made available in DSpace on 2014-12-15T21:10:12Z (GMT). No. of bitstreams: 1 8701463.pdf: 5943652 bytes, checksum: 0189d30faaf25814cad180a92cc1cce0 (MD5) Previous issue date: 1986","Embargo set by: Seth Robbins for item 70259 Lift date: Forever Reason: Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","Restricted to the U of I community idenfinitely during batch ingest of legacy ETDs","U of I Only","217 p.","Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1986."],"dc:identifier":["http://hdl.handle.net/2142/70093","(UMI)AAI8701463"],"dc:subject":["Agriculture, Food Science and Technology"],"dc:title":["Chemical and Chromatographic Studies on Dimeric Fatty Acids (Heated Fats)"],"dc:type":["text"],"thesis:degree_discipline":["Food Science"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:02Z"}