The speciation of aluminum in solutions of alum and various prehydrolyzed, aluminum-based water treatment coagulants was investigated by 27Al NMR at 5 degrees C and 25 degrees C. Alum solutions were seen to contain only mononuclear species including an AlSO4(+) complex, while the prehydrolyzed coagulant solutions contained polynuclear aluminum species, as well. The relative proportions of both polynuclear species and AlSO4(+) complex decreased in cold water. The presence of organic matter had little effect on the speciation of aluminum in diluted alum, but markedly reduced the relative proportion of the tridecamer species in the prehydrolyzed coagulant solutions. The relationship between Al speciation in the coagulants and organic matter removal during jar tests was considered, and the possible role of sulfate in both the formation of the tridecamer species and the effect of organic matter on coagulation efficiency was discussed.
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http://dx.doi.org/10.1016/S0043-1354(03)00229-X | DOI Listing |
J Anim Sci Biotechnol
January 2025
College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Background: The diverse types and processing methods of grains intricately influence the sites and digestibility of starch digestion, thereby impacting energy utilization. This study aimed to explore the impact of grain variety and processing methods on the net energy (NE) in dairy goats, analyzing these effects at the level of nutrient digestion and metabolism.
Methods: Eighteen castrated Guanzhong dairy goats (44.
Sci Total Environ
January 2025
Department of Environmental Engineering, Faculty of Engineering, Khon Kaen University, Khon Kaen 40002, Thailand; Research Center for Environmental and Hazardous Substance Management, Khon Kaen University, Khon Kaen 40002, Thailand. Electronic address:
Chlorine (Cl) and chlorine dioxide (ClO) are commonly used to disinfect water but unfavorable interactions with dissolved organic matter (DOM) result in the formation of disinfection byproducts (DBPs). This study investigated the formation of organic DBPs arising from Cl and ClO disinfections under different contact times in two surface waters in Thailand and Suwannee River natural organic matter with/without bromide using unknown screening analysis with Orbitrap mass spectrometry. Many CHOCl-DBPs and CHOBr-DBPs intermediates were rapidly formed during the initial period of contact (5-30 min).
View Article and Find Full Text PDFSci Total Environ
January 2025
Key Laboratory of Coastal Biology and Biological Resource Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; University of Chinese Academy of Sciences, Beijing 101408, China. Electronic address:
The biogeochemical processes of organic matter exhibit notable variability and unpredictability in marginal seas. In this study, the abiologically and biologically driving effects on particulate organic matter (POM) and dissolved organic matter (DOM) were investigated in the Yellow Sea and Bohai Sea of China, by introducing the cutting-edge network inference tool of deep learning. The concentration of particulate organic carbon (POC) was determined to characterize the status of POM, and the fractions and fluorescent properties of DOM were identified through 3D excitation-emission-matrix spectra (3D-EEM) combined parallel factor analysis (PARAFAC).
View Article and Find Full Text PDFSci Total Environ
January 2025
College of Environmental Science and Engineering, Tongji University, State Key Laboratory of Pollution Control and Resource Reuse, Ministry of Education Key Laboratory of Yangtze River Water Environment, Shanghai 200092, China; Frontiers Science Center for Intelligent Autonomous Systems, Shanghai 200092, China; Institute of Carbon Neutrality, Tongji University, Shanghai 200092, China. Electronic address:
Mangrove ecosystems, a type of blue carbon ecosystems (BCEs), are vital to the global carbon cycle. However, the combined effects of microplastics (MPs) and plastic additives on carbon sequestration (CS) in mangroves remain unclear. Here, we comprehensively review the sources, occurrence, and environmental behaviors of MPs and representative plastic additives in mangrove ecosystems, including flame retardants, such as polybrominated diphenyl ethers (PBDEs), and plasticizers, such as phthalate esters (PAEs).
View Article and Find Full Text PDFJ Hazard Mater
December 2024
School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen 518055, PR China. Electronic address:
The persistence and ecological impact of per- and poly-fluoroalkyl substances (PFAS) in water sources necessitate effective and energy-efficient treatment solutions. This study introduces a novel approach using cerium dioxide (CeO) electrodes enhanced with oxygen vacancy (O) to catalyze the defluorination of PFAS. By leveraging the unique affinity between cerium and fluorine-containing species, our approach enables adsorptive preconcentration and catalytic degradation at low oxidation potentials (1.
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