% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Beauvois:888322,
author = {Beauvois, Anthony and Vantelon, Delphine and Jestin,
Jacques and Rivard, Camille and Bouhnik-Le Coz, Martine and
Dupont, Aurélien and Briois, Valérie and Bizien, Thomas
and Sorrentino, Andrea and Wu, Baohu and Appavou,
Marie-Sousai and Lotfi-Kalahroodi, Elaheh and
Pierson-Wickmann, Anne-Catherine and Davranche, Mélanie},
title = {{H}ow does calcium drive the structural organization of
iron-organic matter aggregates? {A} multiscale
investigation},
journal = {Environmental science / Nano},
volume = {7},
number = {9},
issn = {2051-8161},
address = {Cambridge},
reportid = {FZJ-2020-04841},
pages = {2833 - 2849},
year = {2020},
abstract = {Iron–organic matter (Fe–OM) aggregates are a key factor
in the control of pollutant mobility. Their physical and
structural organization depends on the prevailing
physicochemical conditions during their formation and on
subsequent exposure to variations in porewater geochemistry.
Among these conditions, calcium (Ca) could be a major
parameter given its high concentrations in the environment
and its affinity for OM. Mimetic environmental Fe–OM–Ca
associations were synthesized at various Fe/organic carbon
(OC) and Ca/Fe molar ratios using leonardite humic acid as
the OM model. The impact of Ca on Fe–OM aggregates was
studied by a combination of X-ray absorption spectroscopy,
small angle X-ray and neutron scattering and imaging
techniques (TEM, cryo-TEM and cryo-TXM). Iron phases are
constituted of Fe(III)-oligomers, Fe(III)-nanoparticles and
ferrihydrite (Fh), all bound to or embedded in OM. Iron
phases exhibit a fractal organization with Fe-primary beads
aggregated as Fe-primary aggregates (Fe-PA) which themselves
are embedded in OM aggregates. For Ca/OC (mol mol−1) <
0.026, Fe-PA aggregate in a third level as an Fe-secondary
aggregate. For Ca/OC ≥ 0.026, OM forms a large Ca-branched
network in which Ca is bound as a dimer to OM carboxylic
sites. Under such conditions, Fe-PA are distributed in the
OM network, distant from each other. All these structural
transitions are driven by Ca which partially screens the
Fe–OM interactions. The formation of such a micrometric
network should impact both the surface reactivity of the Fe
phases and the mobility of Fe, OM and associated elements,
notably in soil pores where they are produced under natural
conditions},
cin = {JCNS-FRM-II / JCNS-1 / MLZ},
ddc = {333.7},
cid = {I:(DE-Juel1)JCNS-FRM-II-20110218 /
I:(DE-Juel1)JCNS-1-20110106 / I:(DE-588b)4597118-3},
pnm = {6G15 - FRM II / MLZ (POF3-6G15) / 6G4 - Jülich Centre for
Neutron Research (JCNS) (POF3-623)},
pid = {G:(DE-HGF)POF3-6G15 / G:(DE-HGF)POF3-6G4},
experiment = {EXP:(DE-MLZ)KWS2-20140101 / EXP:(DE-MLZ)KWS3-20140101},
typ = {PUB:(DE-HGF)16},
UT = {WOS:000570558000025},
doi = {10.1039/D0EN00412J},
url = {https://juser.fz-juelich.de/record/888322},
}