Related Experiment Video
Updated: Feb 9, 2026

Identification of Post-translational Modifications of Plant Protein Complexes
Published on: February 22, 2014
Identification of Bernalite Transformation and Tridentate Arsenate Complex at Nano-goethite under Effects of Drying,
1Department of Agricultural Biotechnology and Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
Abstract:
The structural configuration of arsenate on iron (hydr)oxide determines its leachability and bioavailability in the soil environment. It is important to understand how the stability of iron hydroxide and the structural configuration of arsenate complexes vary in response to changes in environmental conditions. Therefore, we investigated the effects of drying, pH and surface loadings on the stability of goethite and the structural configuration of arsenate through batch experiments and TEM and XAS measurements with DFT calculation. As a result, we observed no significant transformation of goethite under most conditions, but TEM confirmed the partial formation of bernalite in the presence of arsenate at a pH of 10, and the bernalite showed 2.18 times higher arsenate sorption than the goethite. The linear combination fitting of the EXAFS spectra with DFT calculations revealed that tridentate and bidentate complexes were dominant under low surface loading and pH conditions in the sedimented samples, while monodentate complexes were abundant under high surface loading and pH conditions. Based on our results, we conclude that the formation of arsenic-rich colloids could account for mobilization in the soil environment, and the density of available sorption sites combined with the concentration of solute could cause the change in structural configuration.
Related Concept Videos
Factors Affecting Dissolution: Particle Size and Effective Surface Area
Bacterial Transformation
Griffith made an unexpected discovery when he killed the pathogenic strain and mixed its remains with the live, non-pathogenic strain. Not only did the mixture kill host mice, but it also contained living pathogenic bacteria that...
Dry Friction
To illustrate this concept, imagine a wooden crate resting on a rough, non-uniform horizontal surface. When an external force is applied to...
Drying Shrinkage
A portion of this drying shrinkage can be reversed; if the concrete is...
Transformers
The iron core has a substantial relative permeability. Therefore, the magnetic field lines generated due to the current in one winding are almost entirely confined within the core, such that the same magnetic flux permeates each turn of both...
Transformation

