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Abstract 3‐Acetamido‐5‐acetylfuran (3A5AF) is a potential platform compound for the production of nitrogen‐containing pharmaceuticals and chemicals. 3A5AF can be obtained by dehydration of chitin or its monomer, N‐acetylglucosamine (NAG). Here, we examined the use of solid catalysts for the dehydration of NAG to 3A5AF to achieve a more economical process that uses a recyclable catalyst. NAG was dehydrated using various solid catalysts in the presence of NaCl and N,N‐dimethyl acetamide as solvent at 433 K. The yield of 3A5AF with the solid catalysts decreased in the following order: Al‐exchanged montmorillonite>H‐ZSM‐5 (SiO2/Al2O3=40)>H‐montmorillonite (K‐10)>Amberlyst15>H‐ZSM‐5 (SiO2/Al2O3=300)>TiO2>γ‐Al2O3>ZrO2>SiO2 ⋅ MgO>Na‐montmorillonite. The highest yield of 3A5AF (14 %) was obtained with the Al‐exchanged montmorillonite. The montmorillonite catalysts were characterized by using inductively coupled plasma optical emission spectroscopy, energy‐dispersive X‐ray spectroscopy, N2 adsorption, Fourier‐transformed infrared spectroscopy, X‐ray diffraction, and 27Al magic‐angle spinning nuclear magnetic resonance spectroscopy (MAS‐NMR). In addition, a combined catalyst of Al‐exchanged montmorillonite and Cl− from synthetic hydrotalcite was found to be an active and recyclable solid catalyst for NAG dehydration to 3A5AF.

Abstract Although chitin, an N‐acetyl‐D‐glucosamine polysaccharide, can be converted to valuable products by means of homogeneous catalysis, most of the chitin generated by food processing is treated as industrial waste. Thus, a method for converting this abundant source of biomass to useful chemicals, such as lactic acid, would be beneficial. In this study, we determined the catalytic activities of various metal oxides for chitin conversion at 533 K and found that MgO showed the highest activity for lactic acid production. X‐ray diffraction analysis and thermogravimetry‐differential thermal analysis showed that the MgO was transformed to Mg(OH)2 during chitin conversion. The highest yield of lactic acid (10.8 %) was obtained when the reaction was carried out for 6 h with 0.5 g of the MgO catalyst. The catalyst could be recovered as a solid residue after the reaction and reused twice with no decrease in the lactic acid yield.

Objective: The purpose of this study was to investigate the effect of listening to music on sleep quality in university students and to explore the influence of preferred music on this effect. Methods: University students identified by the Pittsburgh Sleep Quality Index (PSQI) as 'poor' sleepers (global score > 5) were assigned to three groups (a prescribed music group, preferred music group, and no-music group). During the period of intervention, the prescribed music group and preferred music group listened to their assigned type of music at home every day at bedtime. Results: Global PSQI scores after the intervention were significantly lower in the prescribed music group and preferred music group, but there was no significant reduction in the no-music group. Between the designated sedative music group and the each subject's preferred music group, both the PSQI score showed significant differences in several items, but variations were found in the results. Conclusions: This study confirms that listening to music improves sleep quality, even among university students in Japan. Sleep quality was improved in both prescribed and preferred music groups, although the groups gave different responses to specific PSQI components, which suggests that sleep is potentially affected by music type. [ABSTRACT FROM AUTHOR]