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The discharge of wastewater containing phenol and Its derivatives causes serious position to water re¬sources. In order to solve the problem, SiO2-Cu2 and SiO2-CuO catalysts were prepared by impregnation, calcination and other treatment methods, using the laboratory-made SiO2 particles as the catalyst career to support the five center Cu (II). And the prepared catalysts were applied to the CWPO of phenol. Based on the conversion of phenol after degraded in aqueous solution and the COD removal rate of the sample, the effects of reaction conditions such as reaction temperature, reaction time, oxidant concentration, catalyst concentration and initial pH value of the medium on the catalytic performance of the two catalysts were systematically studied. The experimental results show that the SiO2-Cu2 and SiO2-CuO catalysts have excipient catalytic activity in a wide pH range, and the 100% phenol conversion rate and about 90% COD removal rate can be achieved under the conditions of phenol concentration of 1.0 g/L, catalyst concentration of 0.23 g/L, reaction temperature of 70 °C, reaction time of 20 h, and hydrogen peroxide concentration of 5,0 g/L. [ABSTRACT FROM AUTHOR]

Enhancing protein stability is pivotal in the field of protein engineering. Protein self-cyclization using peptide a tagging system has emerged as an effective strategy for augmenting the thermostability of target proteins. In this study, we utilized a novel peptide tagging system, ReverseTag/ReverseCatcher, which leverages intramolecular ester bond formation. Initially, we employed GFP as a model to validate the feasibility of cyclization mediated by ReverseTag/ReverseCatcher in improving the protein thermostability. Cyclized GFP (cGFP) retained 30 % of its relative fluorescence after a 30-min incubation at 100 °C, while both GFP and linear GFP (lGFP) completely lost their fluorescence within 5 min. Additionally, we applied this method to exo-inulinase (EXINU), resulting in a variant named cyclized EXINU (cEXINU). The T 50 and t 1/2 values of cEXINU exhibited significant enhancements of 10 °C and 10 min, respectively, compared to EXINU. Furthermore, post-cyclization, EXINU demonstrated a broad operational pH range from 5 to 10 with sustained catalytic activity, and cEXINU maintained a half-life of 960 min at pH 5 and 9. Molecular dynamics simulations were conducted to elucidate the mechanisms underlying the enhanced thermostability and pH robustness of EXINU following cyclization. This study highlights that cyclization substanitially enhances the stability of both highly stable protein GFP and low-stable protein EXINU, mediated by the ReverseTag/ReverseCatcher tagging system. The ReverseTag/ReverseCatcher tagging system proves to be a potent conjugation method, with potential applications in improving thermostability, pH robustness, and other areas of protein engineering., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)