The kinetics of the reaction of sulfate radicals with the IHSS Waskish peat fulvic acid in water was investigated in the temperature range from 289.2 to 305.2 K. The proposed mechanism considers the reversible binding of the sulfate radicals by the fulvic acid. The kinetic analysis of the data allows the determination of the thermodynamic parameters DeltaG degrees = -10.2 kcal mol(-1), DeltaH degrees = -16 kcal mol(-1) and DeltaS degrees = -20.3 cal K(-1) mol(-1) for the reversible association at 298.2 K. Theoretical (DFT) calculations performed with the Buffle model of the fulvic acids support the formation of H-bonded adducts between the inorganic radicals and the humic substances. The experimental enthalpy change compares well with the theoretical values found for some of the investigated adducts.
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http://dx.doi.org/10.1039/b900961b | DOI Listing |
J Anim Physiol Anim Nutr (Berl)
January 2025
Faculty of Fisheries and Protection of Waters, South Bohemian Research Centre of Aquaculture and Biodiversity of Hydrocenoses, Institute of Aquaculture and Protection of Waters, University of South Bohemia, České Budějovice, Czech Republic.
Rainbow trout (Oncorhynchus mykiss) is an important fish species raised in aquaculture, but it is susceptible to stress, infections diseases. The present study aimed to determine the effects of fulvic acid feed addition on the systemic and mucosal protective mechanisms of juvenile rainbow trout and to elucidate the underlying molecular mechanisms of changes in the gut. Rainbow trout (4.
View Article and Find Full Text PDFWater Res
December 2024
MOE Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, PR China. Electronic address:
In aqueous environments, microplastics (MPs) undergo photoaging, releasing dissolved organic matter (DOM). Disinfection byproducts (DBPs) formation from natural organic matter (NOM) phototransformation has been reported. However, the impact of NOM on the photoaging of MPs (especially nitrogen-containing MPs) and subsequent nitrogenous DBPs (N-DBPs) formation remains unknown.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
School of Environmental Science and Engineering, Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai Jiao Tong University, Shanghai 200240, China.
In landfill leachates containing complex dissolved organic matter (DOM), the link between individual DOM constituents and their inherent oxidizability is unclear. Here, we resolved the molecular signatures of DOM oxidized by OH/O using FT-ICR MS, thereby elucidating their oxidizability and resistance in concentrated leachates. The comprehensive gradual fragmentation of complex leachate DOM was then revealed through a modified machine-learning framework based on 43 key pathways during ozonation.
View Article and Find Full Text PDFSci Rep
January 2025
Plant Production Department, College of Food and Agriculture Sciences, King Saud University, 11451, Riyadh, Saudi Arabia.
Maize (Zea mays L.) faces significant challenges to its growth and productivity from heavy metal stress, particularly Chromium (Cr) stress, which induces reactive oxygen species (ROS) generation and damages photosynthetic tissues. This study aimed to investigate the effects of fulvic acid (FA) application, via foliar spray or root irrigation, on mitigating chromium stress in maize by evaluating its impact on antioxidant activity and growth parameters.
View Article and Find Full Text PDFMar Environ Res
January 2025
Key Laboratory of Marine Chemistry Theory and Technology, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ministry of Education, Ocean University of China, Qingdao, 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao, 2066061, China. Electronic address:
The world's largest green tide, caused by Ulva prolifera, in the Yellow Sea negatively affects the social and economic development of China's coastal region. The dissolved organic matter (DOM) released from U. prolifera is a potential threat to the offshore ecological health.
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