{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23486"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23486","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Effects of structural iron oxidation state on the hydraulic conductivity and potassium fixation of smectite clays and soils","abstract":"Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","abstract_html":"Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","abstract_has_math":false,"creators":["Shen, Siyuan"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Agriculture, Agronomy","degree_department":null,"school":null,"contributors":["Stucki, Joseph W.","Boast, Charles W."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T14:15:58Z","date_published":"2011-05-07T14:15:58Z","updated_at":"2026-07-22T22:25:22Z","subjects":["Agriculture, Agronomy","Mineralogy","Chemistry, Agricultural"],"languages":["eng"],"rights":["Copyright 1994 Shen, Siyuan"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9512547","(UMI)AAI9512547"],"render_values":[{"text":"AAI9512547","href":null,"code":true},{"text":"(UMI)AAI9512547","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23486","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Stucki, Joseph W.","Boast, Charles W."]},{"key":"dc:creator","label":"Author","values":["Shen, Siyuan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T14:15:58Z","10000-01-01","1994"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Agriculture, Agronomy","Mineralogy","Chemistry, Agricultural"]},{"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, Agronomy","Mineralogy","Chemistry, Agricultural"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1994 Shen, Siyuan"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9512547","(UMI)AAI9512547","http://hdl.handle.net/2142/23486"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","Changes in oxidation states of structural Fe in smectites altered the physicochemical properties of the minerals, which is of great importance to agriculture and environment because the permeability of soils and availability of plant nutrients depends in large degree on these properties of clays.","Two smectites (SWa-1 and API 25) and the clay fraction of Batestown till with different saturating cations (Na$\\sp+$, K$\\sp+$, and Ca$\\sp{2+}$) were reduced by sodium dithionite (Na$\\sb2$S$\\sb2$O$\\sb4$) or sulfide (Na$\\sb2$S), both in suspension and in situ after consolidation. The results indicated structural Fe reduction altered the hydraulic conductivity of the clays. The changes in hydraulic conductivity depended on both the oxidation state and consolidation history of the clay, and the choice of reducing agents and saturating cations.","The swelling of K-saturated SWa-1 was determined and compared with the swelling of Na-smectite at various Fe oxidation states. The results indicated that the swelling of oxidized K-smectite was much less than that of oxidized Na-smectite. Structural Fe reduction decreased the swelling of Na-smectite, but increased the swelling of K-smectite. The swelling of reduced K- and Na-smectite was similar.","The two smectites, one illite (Fithian), and the clay fractions from the A horizon of three Illinois soils were studied by different methods and techniques. The results indicated that the structural Fe reduction altered the distribution of K between exchangeable and fixed states. In smectites, Fe reduction increased K fixation without changing the amount of exchangeable K. In Illite, the reduction treatment released K to the surrounding solution. The behavior of soil clays is thus largely dependent on the type of clay minerals and the original fixed K content. Redox cycling increased the amount of residual Fe(II), and also altered the fixed K in the clays.","Made available in DSpace on 2011-05-07T14:15:58Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9512547.pdf: 5772806 bytes, checksum: ed5d516d5c6e190db79fbff3d7550f1d (MD5) Previous issue date: 1994","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:04:48Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:59-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Effects of structural iron oxidation state on the hydraulic conductivity and potassium fixation of smectite clays and soils"]}]}],"canonical_facts":{"dc:contributor":["Stucki, Joseph W.","Boast, Charles W."],"dc:creator":["Shen, Siyuan"],"dc:date":["2011-05-07T14:15:58Z","10000-01-01","1994"],"dc:description":["Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","Changes in oxidation states of structural Fe in smectites altered the physicochemical properties of the minerals, which is of great importance to agriculture and environment because the permeability of soils and availability of plant nutrients depends in large degree on these properties of clays.","Two smectites (SWa-1 and API 25) and the clay fraction of Batestown till with different saturating cations (Na$\\sp+$, K$\\sp+$, and Ca$\\sp{2+}$) were reduced by sodium dithionite (Na$\\sb2$S$\\sb2$O$\\sb4$) or sulfide (Na$\\sb2$S), both in suspension and in situ after consolidation. The results indicated structural Fe reduction altered the hydraulic conductivity of the clays. The changes in hydraulic conductivity depended on both the oxidation state and consolidation history of the clay, and the choice of reducing agents and saturating cations.","The swelling of K-saturated SWa-1 was determined and compared with the swelling of Na-smectite at various Fe oxidation states. The results indicated that the swelling of oxidized K-smectite was much less than that of oxidized Na-smectite. Structural Fe reduction decreased the swelling of Na-smectite, but increased the swelling of K-smectite. The swelling of reduced K- and Na-smectite was similar.","The two smectites, one illite (Fithian), and the clay fractions from the A horizon of three Illinois soils were studied by different methods and techniques. The results indicated that the structural Fe reduction altered the distribution of K between exchangeable and fixed states. In smectites, Fe reduction increased K fixation without changing the amount of exchangeable K. In Illite, the reduction treatment released K to the surrounding solution. The behavior of soil clays is thus largely dependent on the type of clay minerals and the original fixed K content. Redox cycling increased the amount of residual Fe(II), and also altered the fixed K in the clays.","Made available in DSpace on 2011-05-07T14:15:58Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9512547.pdf: 5772806 bytes, checksum: ed5d516d5c6e190db79fbff3d7550f1d (MD5) Previous issue date: 1994","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:04:48Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:30:59-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9512547","(UMI)AAI9512547","http://hdl.handle.net/2142/23486"],"dc:language":["eng"],"dc:rights":["Copyright 1994 Shen, Siyuan"],"dc:subject":["Agriculture, Agronomy","Mineralogy","Chemistry, Agricultural"],"dc:title":["Effects of structural iron oxidation state on the hydraulic conductivity and potassium fixation of smectite clays and soils"],"dc:type":["text"],"thesis:degree_discipline":["Agriculture, Agronomy","Mineralogy","Chemistry, Agricultural"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:22Z"}