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[Display omitted] • The maximum removal rate of residual lincomycin in LMRs was up to 98.38 % at 200 °C. • Protein and lignin/CRAMs compounds displayed the highest reactivity during AHT. • Humic acids were produced via a novel "Radicals-based polymerization" pathway. • Fatty acid and indole derivative were regarded as plant-growth-promoting compounds. Fermentation-based antibiotic production results in the generation of nutrient-rich antibiotic mycelial residues with significant recycling potential. However, the high concentration of residual antibiotics restricts their application in high-value contexts. This study employs an alkali-thermal humification treatment (AHT) to safely manage lincomycin mycelial residues (LMRs) and assesses the feasibility of the resulting LMRs liquid as organic fertilizer. The removal efficiency for lincomycin attains 98.38 % at 200 °C under AHT. Density functional theory calculations combined with liquid chromatography tandem mass spectrometry (LC-MS/MS) reveal that hydrothermal degradation of lincomycin occurs through processes such as hydrolyzation, N-demethylation, hydroxylation, and desulfurization. Post AHT, the LMRs liquid contains substantial quantities of amino acids (2.9 g/L) and humic acid (17.29 g/L) at 200 °C. Molecular networking identifies fatty acids and indole derivatives as plant-growth-promoting compounds in LMRs liquid, rendering it an appealing option for organic fertilization. Furthermore, a new pathway termed "Radicals-based polymerization" is proposed, which augments humic acid yield and organic stabilization. This study provides valuable insights into the comprehensive removal of antibiotics while concurrently recovering plant-growth-promoting compounds from antibiotic mycelial residues through the application of the AHT process. [ABSTRACT FROM AUTHOR]

Numerical simulation has become a pivotal method in geotechnical engineering for analyzing rock failure. However, traditional model lacks comprehensive elastoplastic rock characterization. Therefore, a new finite-discrete element model using the Drucker-Prager criterion and cohesive elements based on a traction-separation law to accurately simulate elastoplastic rock breaking has been built. A scratch test simulation is conducted to describe the mechanical response and failure characteristics of the rock during the cutting process. Rock failure characteristics derived from numerical simulations align closely with experimental observations. These simulations successfully replicate both the ductile and brittle regimes observed during scratch tests. Furthermore, they provide insights into the primary driving factors behind rock failure under different regimes. Variation of cutting force and specific energy obtained from the model are entirely consistent with experimental results, with the specific energy decreasing following a −0.5 power law, thus explaining the energy dissipation rule of the specific energy decrease. In brittle regime, crush zones and the resulting rough shearing surface are observed, plastic damage is also found, revealing that the cutter tip is the key structure influencing them. The model established in this paper holds significant importance for rock mechanical property evaluation and the optimization design of cutter structures. [ABSTRACT FROM AUTHOR]