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The catalytic conversion of biomass-derived glycerol into high-value-added products, such as glyceric acid (GLYA), using catalyst-supported Au nanoparticles (Au NPs) at room temperature presents a significant challenge. In this study, we constructed a series of supported Au catalysts, including Au/ZrO 2 @C, Au/C, Au/ZrO 2 , and Au/ZrO 2 -C, and investigated their effectiveness in selectively catalytic oxidizing glycerol to GLYA at room temperature. Among these catalysts, the Au/ZrO 2 @C catalyst exhibited the best catalytic performance, achieving a glycerol conversion rate of 73% and a GLYA selectivity of 79% under the optimized reaction conditions (reaction conditions: 30 mL 0.1 M glycerol, glycerol/Au = 750 mol mol -1 , T = 25 °C, p (O 2 ) = 10 bar, stirring speed = 600 rpm, time = 6 h). Physical adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and other characterization methods were employed to analyze the texture properties of the catalyst. The findings indicated that the support structure, the strong metal-support interactions between Au NPs and the support, and the presence of small metallic Au NPs were the primary factors contributing to the catalyst's high activity and selectivity. Moreover, the reusability of the Au/ZrO 2 @C catalyst was investigated, and a probable reaction mechanism for the oxidation of glycerol was proposed., Competing Interests: The authors declare that they have no competing interests., (This journal is © The Royal Society of Chemistry.)

Ochratoxin A (OTA) is a common food contaminant with multiple toxicities and thus rapid and accurate detection of OTA is indispensable to minimize the threat of OTA to public health. Herein a novel enzyme cascade-amplified immunoassay (ECAIA) based on the mutated nanobody-alkaline phosphatase fusion (mNb-AP) and MnO 2 nanosheets was established for detecting OTA in coffee. The detection principle is that the dual functional mNb-AP could specifically recognize OTA and dephosphorylate the ascorbic acid-2-phosphate (AAP) into ascorbic acid (AA), and the MnO 2 nanosheets mimicking the oxidase could be reduced by AA into Mn 2+ and catalyze the 3,3',5,5'-tetramethyl benzidine into blue oxidized product for quantification. Using the optimal conditions, the ECAIA could be finished within 132.5 min and shows a limit of detection of 3.38 ng mL -1 (IC 10 ) with an IC 50 of 7.65 ng mL -1 and a linear range (IC 20 -IC 80 ) of 4.55-12.85 ng mL -1 . The ECAIA is highly selective for OTA. Good recovery rates (84.3-113%) with a relative standard deviation of 1.3-3% were obtained and confirmed by high performance liquid chromatography with a fluorescence detector. The developed ECAIA was demonstrated to be a useful tool for the detection of OTA in coffee which provides a reference for the analysis of other toxic small molecules., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This study reveals the first attempt to apply PTFE hollow fiber membranes for removing ultrafine particles in PM 2.5 . The asymmetric polytetrafluoroethylene (PTFE) hydrophobic hollow fiber membranes were prepared through a cold pressing method including paste extrusion, stretching and heating. The reduction ratio, stretching ratio and heating temperature have influences on the morphology, structure, porosity, shrinkage ratio, tensile strength and permeability of the PTFE hollow fiber membranes. The morphological properties of the PTFE hollow fiber membrane were studied using field emission scanning electron microscopy (FESEM). The increase of stretching ratio can improve the pore size and porosity of the hollow membrane, but be negative for the mechanical properties. By changing the reduction ratio we can obtain different inner diameter PTFE hollow fiber membranes. Finally, the PTFE hollow fiber membranes were tested for their performances in the removal of ultrafine particles in PM 2.5 . The PTFE hollow fiber membranes had the microstructure of nodes interconnected by fibrils, designed to possess the synergistic advantages of porous filters and fibrous filters with a sieve-like outer surface and a fibrous-like porous substrate. Under dead-end filtration, the filtration efficiency is related to the wall thickness, pore size and porosity of the membranes. The air filtration achieved was higher than 99.99% for PM 2.5 and 90% for PM 0.3 , indicating that all the prepared PTFE hollow fiber membranes exhibited satisfactory removal of ultrafine particles performances. Because of the hydrophobicity, PTFE hollow fiber membranes have self-cleaning ability and a large dust-holding capacity of >120 g m -2 , slowing down membrane fouling. The fouled filter media after washing retained a high filtration efficiency without obvious deterioration. The hydrophobic PTFE hollow fiber membranes developed in this work exhibited potential applications in air filtration., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)