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Updated: Oct 30, 2025

Quantification of Humic and Fulvic Acids in Humate Ores, DOC, Humified Materials and Humic Substance-Containing Commercial Products
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Quantification of Humic and Fulvic Acids in Humate Ores, DOC, Humified Materials and Humic Substance-Containing Commercial Products

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EPR Spectroscopy as a Tool to Characterize the Maturity Degree of Humic Acids

Bozena Debska1, Ewa Spychaj-Fabisiak1, Wiesław Szulc2

  • 1Department of Biogeochemistry and Soil Sciences, University of Science and Technology, 6 Bernardynska St., 85-029 Bydgoszcz, Poland.

Materials (Basel, Switzerland)
|July 2, 2021
PubMed
Summary

Humic acids (HAs) from different origins show distinct properties detectable by electron paramagnetic resonance (EPR) spectroscopy. Forest soil HAs exhibit higher spin concentration and narrower EPR spectra compared to plant-derived HAs.

Keywords:
EPRfluorescence spectroscopyforest soilhumic acidsplant material of wheat

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