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Silt and mucky soil have high natural moisture content, poor water permeability, high compressibility, low strength, and a large void ratio. Silt and mucky soil solidify by adding cement in practical projects. In this work, the erosion characteristics of the silt and mucky soil have improved by adding steel slag powder to it. This paper compared the mechanical properties of the solidified soil with that of the pure cement-solidified sludgy soil under the same erosion environment. The physical properties and the erosion mechanism of the solidified soil were analyzed in macroscopic and microscopic aspects. Our findings show that the strength range of the solidified soil sample mixed with steel slag powder is 0.028, and the strength change range of the sample mixed with cement soil is 0.062. It can see that the steel slag powder and its hydration products have effectively improved resistance to ions erosion of the solidified soil. When chloride ions and sulfate ions coexist in the erosion solution, chloride ions can delay the erosion rate of sulfate ions on the solidified soil and improve the compressive strength of the solidified soil. The higher the chloride ions concentration, the more pronounced the effect. As the concentration of SO42−:Cl− increased from 3:1 to 1:3 during the same erosion time, solidified soil mass change rate increased by 0.8%. Finally, SEM images were used to analyze the microstructure changes of the solidified soil with Sulfate–chloride mixed solution and discussed the erosion and damage mechanism of solidified soil. [ABSTRACT FROM AUTHOR]

Traditional degumming methods of bast fibers are largely limited due to long procedures, high energy consumption, serious environmental pollution, or low efficiency. In this study, deep eutectic solvents (DESs) synthesized with hydrogen bond acceptor (HBA) and three representative hydrogen bond donors (HBDs) were applied to kenaf bast degumming. The morphologies, chemical compositions, crystallinities, polymerization degrees and physical properties of the kenaf fibers were determined. The effects and mechanisms of different DESs on dispersing kenaf bast were discussed. The results showed that alkalinity amide DES (ChCl-urea, CU) showed the best degumming effect. The optimal processing temperature is 160 °C and the processing time is 2 h. Due to competition from chloride ions, DES first weakens the hydrogen bond interaction in kenaf fibers. Then, the alkalinity amide DES removed lignin by deprotonation of phenolic hydroxyl groups and breakage of β-O-4 bonds for different lignin units. Finally, the solvent can be reused at least 3 times. The results showed that CU degumming treatment could effectively remove the gummy components in kenaf bast and had the potential to prepare refined dry kenaf fibers. This study provided a simple and green degumming method for kenaf bast. [Display omitted] • A facile and greener DES degumming method for preparation of kenaf fibers. • Recycable and reusable DES degumming waste. • The mechanisms of kenaf bast degumming by three kind of DESs. [ABSTRACT FROM AUTHOR]