Xylitol is a valuable sweetener produced from xylose-rich biomass. Our objective was to optimize conditions for maximum release of D-xylose from wheat straw by acid or enzyme hydrolysis with minimal release of other monosaccharides, and to purify xylitol from three other alditols. Ground straw was treated with 10 parts of 0.2-0.4 M sulfuric acid at 110-130 degrees C for 15-45 min or at reflux with 0.75-1.25 M sulfuric acid for 1.5-3 h. Under optimum conditions of either 0.3 M acid at 123 degrees C for 28 min or 1.0 M acid at 100 degrees C for 3 h, 18 or 19% of D-xylose plus approximately 6% other sugars were produced from straw (dry basis). A 16% yield of D-xylose plus 6% other sugars was obtained when hydrothermally (10% straw, 160 degrees C, 1 h) treated straw was incubated with a commercial xylanase. The lack of enzyme specificity for D-xylose release was attributed to the autohydrolysis of polysaccharides during the pretreatment plus slow hydrolysis of cellulose during enzyme digestion. Xylitol with a purity of 95% was obtained in 10% yield from straw after the reduction of an acid-hydrolyzate followed by fractional crystallization. Purification of the mixture of four alditols by open-column chromatography on a strongly basic anion-exchange resin in hydroxide form gave 7% xylitol crystals with a purity of 99%.

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Anti-perovskites X 3 BA, as the electrically inverted derivatives of perovskites ABX 3 , have attracted tremendous attention for their good performances in multiple disciplines, especially in energy storage batteries. The Li/Na-rich antiperovskite (LiRAP/NaRAP) solid-state electrolytes (SSEs) typically show high ionic conductivities and high chemical/electrochemical stability toward the Li-metal anode, illustrating their great potential for applications in the Limetal batteries (LMBs) using nonaqueous liquid electrolyte or all-solid-state electrolyte. The antiperovskites have been studied as artificial solid electrolyte interphase for Li-metal anode protection, film SSEs for thin-film batteries, and low melting temperature solid electrolyte enabling melt-infiltration for the manufacture of all-solid-state lithium batteries. Transition metal-doped LiRAPs as cathodes have demonstrated a high discharge specific capacity and good rate capability in the Li-ion batteries (LIBs). Additionally, the underlying scientific principles in antiperovskites with flexible structural features have also been extensively studied. In this review, we comprehensively summarize the development, structural design, ionic conductivity and ion transportation mechanism, chemical/electrochemical stability, and applications of some antiperovskite materials in energy storage batteries. The perspective for enhancing the performance of the antiperovskites is also provided as a guide for future development and applications in energy storage. K E Y W O R D S antiperovskite, chemical and electrochemical stability, energy storage, solid-state electrolyte Zhi Deng and Dixing Ni contributed equally to this work.

The present study was executed to analyze the functional phytochemicals of hulless barley grass grown under different intensities of ultraviolet stress. The wheat seedlings were imposed to 0.5, 1.0, 1.5, 2.0, and 2.5 h ultraviolet radiation and harvested in different times at vegetative stage. Specifically, the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, and chlorophyll were determined and antioxidants capacity was evaluated by OH• and 2,2’-azino-bis­(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging ability. A mathematical model (Technique for Order Preference by Similarity to Ideal Solution, TOPSIS) was also employed for the comprehensive evaluation of functional components of hulless barley grass at different growth stages. The results showed that the UV stress could efficiently improve/preserve the contents of total polyphenols, total flavonoids, total triterpenes, total polysaccharides, proanthocyanidins, chlorophyll a, chlorophyll b, and total chlorophyll, as well as the OH• and ABTS scavenging capacity. TOPSIS evaluation revealed that the highest phytochemical contents were yield on the 15th day under 1.0 h ultraviolet treatment.

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