{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,9,13]],"date-time":"2025-09-13T16:34:16Z","timestamp":1757781256309,"version":"3.32.0"},"reference-count":34,"publisher":"Oxford University Press (OUP)","issue":"7","license":[{"start":{"date-parts":[[1998,7,1]],"date-time":"1998-07-01T00:00:00Z","timestamp":899251200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"},{"start":{"date-parts":[[2009,11,2]],"date-time":"2009-11-02T00:00:00Z","timestamp":1257120000000},"content-version":"vor","delay-in-days":4142,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["setac.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1998,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>The interaction of Fe(III) with two samples of fulvic acids (FAs) extracted from a pinewood soil (FA2: horizon 0\u201310 cm; FA3: horizon 10\u201325 cm) was monitored by synchronous fluorescence (SyF) spectroscopy at four pH values (3, 4, 5, and 6). Spectral data were preprocessed by SIMPLISMA, a self-modeling curve-resolution method, and from the calculated quenching profiles, equilibrium parameters for the interaction of Fe(III) and FAs were obtained (conditional stability constants [Kcs] and ligand site concentrations). The calculated log Kcs were (I = 0.1 M KNO3; standard deviation in parentheses): FA2, pH = 3, 4.9 (2), pH = 4, 4.7 (2), pH = 5, 5.1 (4), and pH = 6, 5.1 (1); FA3, pH = 3, 5.48 (1); pH = 4, 4.96 (7), pH = 5, 4.89 (1), and pH = 6, 5.1 (2), where I is the ionic strength. These results show that FA forms quite stable soluble complexes with Fe(III) in the acid pH range.<\/jats:p>","DOI":"10.1002\/etc.5620170711","type":"journal-article","created":{"date-parts":[[2010,3,17]],"date-time":"2010-03-17T06:25:54Z","timestamp":1268807154000},"page":"1268-1273","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Effect of pH on complexation of Fe(III) with fulvic acids"],"prefix":"10.1093","volume":"17","author":[{"given":"Joaquim C G Esteves","family":"da Silva","sequence":"first","affiliation":[{"name":"LAQUIPAI, Faculdade de Ci\u011bncias, Chemistry Department, R. Campo Alegre 687, P4150 Porto, Portugal"}]},{"given":"Ad\u00e9lio A S C","family":"Machado","sequence":"additional","affiliation":[{"name":"LAQUIPAI, Faculdade de Ci\u011bncias, Chemistry Department, R. 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