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The efficient transformation of glucose into 5-hydroxymethylfurfural (5-HMF) is crucial for sustainable bio-refinery processes, but achieving high production efficiency remains challenging. In this study, we presented the preparation of Al-containing metal–organic frameworks (MOFs), specifically MIL-53(Al), MIL-53(Al)-NO2, and MIL-53(Al)-NH2, using different ligands as catalysts to enhance the production of 5-HMF from glucose. Comprehensive characterization provided valuable insights into the properties of the synthesized MOFs. The synthesized MOFs exhibited varied MIL-53(Al) states, morphologies, and thermal stabilities based on the different ligands employed, which in turn affected their catalytic performance. Among the Al-containing MOFs synthesized, MIL-53(Al)-NH2 demonstrated remarkable catalytic capabilities for the conversion of glucose to 5-HMF. This MOF achieved an impressive 5-HMF yield of 53% and a reaction selectivity of 54%. The catalytic efficiency was further enhanced by leveraging the synergistic effect of MIL-53(Al)-NH2 in combination with Amberlyst-36, resulting in a 5-HMF yield of 59% and a reaction selectivity of 60%. [ABSTRACT FROM AUTHOR]

The generation of topological spin textures under ultrafast laser pulse excitations and field-free manipulation of topological transitions between different spin textures has attracted enormous interest from the perspective of spintronic applications. Here, we utilize ultrafast electron microscopy to showcase the femtosecond laser pulses excitation on magnetic materials and have generated multiple topological spin textures in an amorphous ferrimagnetic TbFeCo film. Furthermore, the following field-free topological transitions between skyrmions and bubbles with diversified topology are identified via in situ heating the sample in Lorentz transmission electron microscopy. The critical role of uniaxial anisotropy variation on changing the magnetic textures during the heating process is confirmed by micromagnetic simulations. Our results provide a perspective on the generation and transformation of topological spin textures. [ABSTRACT FROM AUTHOR]

5‐hydroxymethylfurfural (5‐HMF) has been considered as an important biomass‐based platform chemical for its wide applications. Currently, the production of 5‐HMF from the catalytic dehydration of glucose is preferred, in which the Brønsted and Lewis acids in catalysts play an important role. Here, it was found that MIL‐53(Al) modified with tin was an active, selective, and reusable catalyst for the transformation of glucose to 5‐HMF in dimethyl sulfoxide (DMSO) solvent. Around 42.3% yield of 5‐HMF with 93% glucose conversion was achieved, when the prepared metal‐organic frameworks (MOFs) was used as the catalyst, showing superior catalytic performance compared with most of other MOFs. Moreover, the catalyst possessed inert catalytic properties in water with almost no any influence on the conversion of glucose, suggesting a compelling opportunity to act as a support material. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, percutaneous kyphoplasty (PKP) has been increasingly used in clinical settings. OBJECTIVE: In this study, we aimed to determine the analgesic effect of intravertebral lidocaine injections in PKP. METHODS: A total of 60 patients who were treated with PKP were enrolled in this study. Lidocaine hydrochloride was chosen as the medication for the experimental group. Patients were randomly assigned into three groups using a double-blind study design: In group A (20 cases), no drugs were injected into the vertebral body during surgery; group B (20 cases) received intravertebral injection of normal saline; and in group C (20 cases), lidocaine hydrochloride was administered into the vertebral body during surgery. The age of patients, operation time, balloon dilatation pressure, balloon dilatation volume, and amount of bone cement injected were compared across the three groups. A pain visual analog scale (VAS) was used to assess pain suffered by the patients before, during, and 24 hours after the surgery. RESULTS: Age, operation time, balloon dilatation pressure, balloon dilatation volume, and amount of bone cement injected did not differ significantly among the three groups (P > 0.05). The differences in VAS scores 24 hours before and after surgery were not statistically significant (P > 0.05). Group C had lower intraoperative VAS scores than groups A and B, and the difference was statistically significant (P < 0.01). There was no statistically significant difference between group A and group B (P > 0.05). CONCLUSION: Intravertebral injections of lidocaine during PKP can successfully reduce intraoperative pain. [ABSTRACT FROM AUTHOR]

Glucose conversion to 5-hydroxymethylfurfural (HMF) is important to the success of a biorefinery. Herein, metal–organic frameworks (MOFs) with the UiO-66 structure were synthesised with decanoic acid as the modulator and used as the catalyst to optimise HMF yield. PXRD, FTIR, and TGA/DSC techniques were applied to characterise the materials. The analysis results show that the materials assembled from the ligand 2-nitroterephthalic acid and hexameric Zr-oxo clusters contain decanoic acid chemically bound in the framework that influences porosity, Lewis acidity, and hydrophobicity. The materials exhibit excellent catalytic performance for HMF production from glucose in DMSO as solvent, attributed to their abundant defects and high hydrophobicity due to the addition of the decanoic acid modulator. Influences of catalyst dosages, reaction duration, and temperature were comprehensively investigated, leading to 98.1% conversion of glucose and 54.5% HMF yield under optimised reaction conditions. The catalytic conversion shows some deterioration after four cycles, yet the reaction selectivity displays no significant decline. [ABSTRACT FROM AUTHOR]

The catalytic characteristics of metal ions for glucose isomerization and dehydration were investigated with metal chloride as catalyst. The influences of metal ion category, content and temperature on reaction process were studied. The reaction kinetic model was applied to correlate experimental data to analyze catalytic characteristics quantitatively. The process of glucose to HMF was a tandem reaction, and the kinetic model based on this mechanism could simulate the reaction accurately. Ni2+, Cr3+ and Sn4+ possessed good catalytic activity for glucose conversion, among which the catalyst activity of Sn4+ was the highest, and that of Ni2+ was the lowest. The kinetic constant of side reaction of Sn4+ was about 20 times of that of Ni2+ . For Ni2+, reaction rate of glucose isomerization and side reaction increased, yet the catalytic activity for fructose dehydration to HMF was negligible with the increasing of Ni2+ content. Increasing of Cr3+ could enhance reaction rate of glucose isomerization significantly, and almost had no effect on other reactions. With the increasing of Sn4+ content, reaction rate of all steps increased, yet the intensity of side reaction would decrease. The influence of temperature on reaction constants followed the Arrhenius model. Higher temperature was beneficial to the side reaction, fructose dehydration and glucose isomerization respectively, when Ni2+, Cr3+ and Sn4+ were used, respectively. [ABSTRACT FROM AUTHOR]