2D PdCu Alloy Nanodendrites Manifest Effective Peroxidase-Like Activity Against Biofilms

Noble metal nanomaterials with peroxidase-like catalytic activity have received great interest lately for their potential applications in biomedicine and environmental protection; however, it is still challenging to achieve high catalytic efficiency despite enormous efforts. In this work, a novel but simple route was developed to synthesize 2D PdCu alloy nanodendrites (PdCu NDs) as a high-performance peroxidase mimic for biofilm elimination. Catalytic kinetics shows that the composition-dependent synergy between Pd and Cu in the PdCu NDs can strongly enhance the peroxidase-like activity. Density functional theory calculations further provide the underlying mechanisms at both atomic and electronic levels for the effective adsorption and dissociation of H2O2 molecules on PdCu NDs surfaces. Owing to their superior peroxidase-like activity, the PdCu NDs exhibit striking biofilm inhibition properties, which suggests that the controlled synthesis of 2D noble metal alloy may open up new opportunities for enhancing enzyme-like activities of noble metal nanomaterials.

An in-situ catalytic-insoluble strategy enabled by sulfurized polyacrylonitrile-based composite cathode for potassium–sulfur batteries

Owing to the insoluble organosulfur mechanism and stable cycling life, sulfurized polyacrylonitrile (SPAN) developed as a promising cathode material for high-energy potassium–sulfur batteries (KSBs). However, it is yet a major challenge to achieve fast catalytic kinetics and high reversible capacity in SPAN-based cathodes. Here, one-step electrospun SPAN nanofibers embedded with Fe[Formula: see text]Nb[Formula: see text]O metal oxide nanoparticles (FeNb@SPAN) have been successfully developed to construct sulfur electrodes with high electrochemical activity, high sulfur utilization, and high cycling stability. The as-prepared freestanding FeNb@SPAN composite cathode, which featuring interwoven nanofibers with Fe[Formula: see text]Nb[Formula: see text]O nanoparticles homogeneously implanted, possesses high storage space for volume expansion and suppresses polysulfide dissolution during potassiation/depotassiation. Benefiting from its unique structure and composition in electrode design, the FeNb@SPAN cathode is endowed with outstanding energy storage performances with a high initial specific capacity of 776 mAh [Formula: see text] g[Formula: see text] under 50 mA [Formula: see text] g[Formula: see text] and an excellent cycling capability of 201 mAh [Formula: see text] g[Formula: see text] after 80 charge/discharge processes. This work heralds a feasible strategy toward SPAN-based sulfur host materials in the structural design of next-generation high-performance cathode materials for KSBs and other metal–sulfur batteries.

On Catalytic Kinetics of Enzymes

Classical enzyme kinetic theories are summarized and linked with modern discoveries here. The sequential catalytic events along time axis by enzyme are analyzed at the molecular level, and by using master equations, this writing tries to connect the microscopic molecular behavior of enzyme to kinetic data (like velocity and catalytic coefficient k) obtained in experiment: 1/k = t equals to the sum of the times taken by the constituent individual steps. The relationships between catalytic coefficient k, catalytic rate or velocity, the amount of time taken by each step and physical or biochemical conditions of the system are discussed, and the perspective and hypothetic equations proposed here regarding diffusion, conformational change, chemical conversion, product release steps and the whole catalytic cycle provide an interpretation of previous experimental observations and can be testified by future experiments.

The catalytic kinetics and cfd simulation of multi-stage combined removal of acrylonitrile tail gas

There is no kinetic data and rate equation that can be used directly for catalytic combustion of acrylonitrile tail gas, which leads to the multi-stage combined catalytic kinetic model of acrylonitrile tail gas collaborative removal. In the actual application process, affected by the internal and external diffusion, this paper proposes the multi-stage combined catalytic kinetic research and CFD simulation analysis of acrylonitrile tail gas collaborative removal. Based on the judgment of multi-stage combined catalytic reaction rules of acrylonitrile tail gas collaborative removal, the multi-stage combined catalytic reaction network of acrylonitrile tail gas collaborative removal is solved by matrix transformation. The possible reaction path in the multi-stage combined catalytic reaction network of acrylonitrile tail gas collaborative removal is solved. For quantitative calculation of product distribution, each step of reaction parameters and dynamic factors are required. According to the mechanism of positive carbon ion reaction, materials were used Studio software and genetic algorithm are used to calculate the dynamic factors and determine the dynamic parameters; the grid automatic generator AutoGrid5 embedded in the Fine/TurboTM software package is used to generate the CFD simulation network, and the iterative algorithm is used to calculate the limit value of the CFD simulation; the S-A model in the CFD simulation platform is used to get the modified value of the dynamic mathematical model, and the dynamic factors and parameters are brought into it to establish the CA mathematical model of multi-stage combined catalytic kinetics for the CO removal of olefine and nitrile tail gas. The experimental results show that, under the same experimental device and parameters, the internal and external diffusion effects of the multi-stage combined catalytic kinetic model of acrylonitrile tail gas collaborative removal are detected. The multi-stage combined catalytic kinetic model of acrylonitrile tail gas collaborative removal in this study uses 10-20 mesh catalyst, and the retention time of acrylonitrile tail gas is less than 4.62 s, the internal and external diffusion will not affect the acrylonitrile tail gas collaborative removal The practical application of the kinetic model for the removal of multi-stage combined catalysis.