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In this work, a novel route to deconstruct cellulose into 5‐hydroxymethylfurfural (HMF) by cascading enzymatic and chemical reactions is reported. For biocatalyst preparation, Fe3O4 nanoparticles encapsulated SBA‐15 with appropriate pore size was synthesized and utilized as magnetic scaffolds for the immobilization of cellulase. For chemical catalyst preparation, sulfated zirconium dioxide conformed monolayers were grafted on SBA‐15 template to create thermally robust mesoporous catalysts with tunable solid basic/Lewis acid and Brønsted acid sites. Catalytic performance of biocatalyst and chemical catalyst was explored in the aqueous phase conversion of IL pretreated cellulose to glucose, and in the iPrOH/water solvent conversion of glucose to HMF conversion, respectively. After the optimization of reaction conditions, a sequential conversion of pretreated cellulose to glucose and glucose to HMF was performed, and 43.6% HMF yield can be obtained. The cascaded enzymatic and chemocatalytic reaction system demonstrates an effective and economically friendly process for biomass energy conservation. A novel route for green conversion of IL pretreated cellulose to 5‐hydroxymethylfurfural (HMF) by cascading an enzymatic catalysis in an aqueous system with chemocatalysis in an iPrOH/water solvent mixture is reported. © 2017 American Institute of Chemical Engineers AIChE J, 2017

By combining micro-Hall probe and magneto-optical imaging techniques we have been able to examine vortex avalanches at different locations of the ridgelike magnetic topography of superconducting niobium samples as the external field is slowly increased. The avalanche size distributions are shown to be power laws for two decades with very similar critical exponents at all locations, thus demonstrating a remarkable robustness in the details of the flux penetration dynamics.

In this work, a facile synthesis of ceria and sulfated zirconia (SZ) incorporated SBA-15 catalyst was conducted. The supported SZ reveals promising Brønsted/Lewis acid and relatively low base strength, and the base strength of the catalyst is significantly enhanced by introducing highly dispersed ceria into the network of SZ incorporated SBA-15. Systematic study of catalyst activities were carried out in iPrOH/DMSO solvent conversion of glucose to 5-hydroxymethylfurfural (HMF). It is found that the isomerization process of glucose to fructose was promoted by coexisting base and Lewis acid sites, and the dehydration reaction of reactively formed fructose to HMF was directed by Brønsted acid sites. Up to 66.5% HMF yield and 70.8% selectivity can be obtained in a 90 vol % iPrOH-mediated DMSO solvent. Through the reaction system developed in this paper, use of a large amount of environmentally hazardous solvent can be avoided, and a new method of large-scale economically viable processes for biomass conservation is provided.