{"id":{"repo_id":"maryland","oai_identifier":"oai:drum.lib.umd.edu:1903/14695"},"canonical_url":"https://search.dev.ndltd.org/etd/maryland/oai:drum.lib.umd.edu:1903/14695","repository":{"repo_id":"maryland","name":"University of Maryland","base_url":"https://api.drum.lib.umd.edu/server/oai/request"},"display":{"title":"EFFECTS OF COMPLEXATION WITH THE SIDEROPHORE DESFERRIOXAMINE B ON TRANSITION METAL REMOVAL FROM SEAWATER","abstract":"Complexation of transition metals with strong organic ligands of unknown structure and origin plays an important role in their behavior and distributions in seawater. I present here a series of stability constants for complexes of several transition metals with the trihydroxamate siderophore desferrioxamine B (DFOB), representative of a class of small organic ligands that are exceptionally selective for Fe(III) and found in open ocean surface waters at low-picomolar concentrations. Stability constants for DFOB complexes with divalent metals are similar to conditional constants that have been measured in seawater for highly metal-specific, but unidentified organic ligands. Titration data indicate that free Hg<super>2+</super> forms a very stable complex with DFOB, however the more toxic methylmercury cation does not. A revised scavenging model for yttrium and the rare earth elements suggests that their removal from seawater is dominated by sorption onto Mn oxides, yet not significantly influenced by biogenic silica or calcite.","abstract_html":"Complexation of transition metals with strong organic ligands of unknown structure and origin plays an important role in their behavior and distributions in seawater. I present here a series of stability constants for complexes of several transition metals with the trihydroxamate siderophore desferrioxamine B (DFOB), representative of a class of small organic ligands that are exceptionally selective for Fe(III) and found in open ocean surface waters at low-picomolar concentrations. Stability constants for DFOB complexes with divalent metals are similar to conditional constants that have been measured in seawater for highly metal-specific, but unidentified organic ligands. Titration data indicate that free Hg&lt;super&gt;2+&lt;/super&gt; forms a very stable complex with DFOB, however the more toxic methylmercury cation does not. A revised scavenging model for yttrium and the rare earth elements suggests that their removal from seawater is dominated by sorption onto Mn oxides, yet not significantly influenced by biogenic silica or calcite.","abstract_has_math":false,"creators":["Christenson, Emily Ann"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":"Marine-Estuarine-Environmental Sciences","school":null,"contributors":[],"advisors":["Schijf, Johan"],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013","date_published":"2013","updated_at":"2026-07-24T03:02:24Z","subjects":[],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1903/14695","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Schijf, Johan"]},{"key":"dc:contributor.department","label":"Department","values":["Marine-Estuarine-Environmental Sciences"]},{"key":"dc:creator","label":"Author","values":["Christenson, Emily Ann"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2013-10-10T05:37:41Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2013-10-10T05:37:41Z"]},{"key":"dc:date.issued","label":"Date","values":["2013"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1903/14695"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Complexation of transition metals with strong organic ligands of unknown structure and origin plays an important role in their behavior and distributions in seawater. I present here a series of stability constants for complexes of several transition metals with the trihydroxamate siderophore desferrioxamine B (DFOB), representative of a class of small organic ligands that are exceptionally selective for Fe(III) and found in open ocean surface waters at low-picomolar concentrations. Stability constants for DFOB complexes with divalent metals are similar to conditional constants that have been measured in seawater for highly metal-specific, but unidentified organic ligands. Titration data indicate that free Hg<super>2+</super> forms a very stable complex with DFOB, however the more toxic methylmercury cation does not. A revised scavenging model for yttrium and the rare earth elements suggests that their removal from seawater is dominated by sorption onto Mn oxides, yet not significantly influenced by biogenic silica or calcite."]},{"key":"dc:title","label":"Title","values":["EFFECTS OF COMPLEXATION WITH THE SIDEROPHORE DESFERRIOXAMINE B ON TRANSITION METAL REMOVAL FROM SEAWATER"]}]}],"canonical_facts":{"dc:contributor.advisor":["Schijf, Johan"],"dc:contributor.department":["Marine-Estuarine-Environmental Sciences"],"dc:creator":["Christenson, Emily Ann"],"dc:date.accessioned":["2013-10-10T05:37:41Z"],"dc:date.available":["2013-10-10T05:37:41Z"],"dc:date.issued":["2013"],"dc:description.abstract":["Complexation of transition metals with strong organic ligands of unknown structure and origin plays an important role in their behavior and distributions in seawater. I present here a series of stability constants for complexes of several transition metals with the trihydroxamate siderophore desferrioxamine B (DFOB), representative of a class of small organic ligands that are exceptionally selective for Fe(III) and found in open ocean surface waters at low-picomolar concentrations. Stability constants for DFOB complexes with divalent metals are similar to conditional constants that have been measured in seawater for highly metal-specific, but unidentified organic ligands. Titration data indicate that free Hg<super>2+</super> forms a very stable complex with DFOB, however the more toxic methylmercury cation does not. A revised scavenging model for yttrium and the rare earth elements suggests that their removal from seawater is dominated by sorption onto Mn oxides, yet not significantly influenced by biogenic silica or calcite."],"dc:identifier.uri":["http://hdl.handle.net/1903/14695"],"dc:title":["EFFECTS OF COMPLEXATION WITH THE SIDEROPHORE DESFERRIOXAMINE B ON TRANSITION METAL REMOVAL FROM SEAWATER"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T03:02:24Z"}