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Hollow Silicalite-1 and ZSM-5 zeolites with hierarchical porous shells have been synthesized by using a dissolution-recrystallization method. The morphology, structure, and acidity of these zeolites supported Pt catalysts were characterized by XRD, FT-IR, MAS-SSNMR, FE-SEM, FE-TEM, N₂-BET, XPS, NH₃-TPD, and CO pulse chemisorption. Compared to the conventional ZSM-5 supported Pt catalyst, the special structure in hollow ZSM-5 zeolite significantly promotes the dispersion of metallic Pt and the synergistic effect between metal active sites and acid sites. These boost the catalytic activity, selectivity of guaiacol hydrodeoxygenation toward cycloalkanes and long-term stability over the Pt/hollow ZSM-5 catalyst combined with improved mass transfer of products and reactants derived from the hierarchical hollow porous structure. Moreover, the Pt/hollow ZSM-5 catalyst exhibits excellent low temperature catalytic activity to completely transform guaiacol into cycloalkanes with the cyclohexane selectivity of more than 93% at 220 °C, suggesting that hollow ZSM-5 zeolite is a promising support for upgrading of bio-oils.

Developing low‐cost and highly efficient electrocatalysts toward oxygen evolution reaction (OER) is of vital significance for electrochemical water splitting. Herein, we fabricate a heterostructure NiS/Ni(OH)x electrocatalyst (Ni‐S‐n) with regenerative oxygen vacancies via electro‐deposition on nickel foam (NF) followed by a facile NaBH4 reduction. The resulting Ni‐S‐5 catalyst with appropriate amount of oxygen vacancies (Ovs) exhibits extraordinary activity for alkaline OER with overpotential of 142 mV and 248 mV to reach the current density of 10 mA cm−2 and 100 mA cm−2, respectively. This catalyst also shows remarkable durability with 40 h. After the stability test, the excellent OER performance is well recovered by regenerating the surface oxygen vacancies (Ovs) significantly with additional NaBH4 reduction. The Ni‐S‐5 catalyst still displays good activity even after repeating it three times (180 h). The surface oxygen vacancies act as vital active sites for OER. A mechanism of Ovs species transformation and regeneration based on the Ni‐S‐5 catalyst is proposed, which provides a new direction for exploring ultrastable and efficient OER electrocatalysts with renewable active species. [ABSTRACT FROM AUTHOR]

Summary: Making noodles based on broken rice (BR) is a green approach to promote the utilisation of rice byproducts (the underutilised bio‐materials with vast annual production). In this study, BR of Indica, Japonica and Glutinous varieties were semi‐dry milled to yield flour (BRI, BRJ and BRG). They were substituted for wheat flour at the level of 10% to prepare W‐BRI, W‐BRJ and W‐BRG noodles respectively. Among three varieties, BRG showed greatest whiteness, highest relative crystallinity and lowest pasting viscosities. Substitution of all BR flours decreased percentage of α‐helix but increased β‐sheet in fresh noodles. BRG substitution markedly enhanced the binding tightness of water to gluten or starch. Owing to the strongest swelling power and lowest pasting temperature (59.1 °C) of BRG, W‐BRG noodles showed shortest cooking time and highest cooking yield (190.64%). All noodles were sensorily acceptable, among which W‐BRG noodles had the greatest softness and least stickiness. W‐BRJ noodles presented more uniform and tightly packed microstructure, which might explain their lowest cooking loss (6.65%) and greater springiness. W‐BRI dough sheet had the most viscoelastic, and its noodles had the highest cohesiveness (0.65). Selective utilisation of rice variety is crucial for producing noodles with characteristic quality. [ABSTRACT FROM AUTHOR]

Developing high‐performance aviation fuel is highly desired for the rapid development of supersonic aircraft. Herein, selective deep hydrogenation of polycyclic aromatics to a high‐density fuel is developed over a Ru‐based catalyst. The influences of strong Ru‐support interaction on tailoring the reaction pathways of acenaphthene hydrogenation were investigated using different oxide supports (SiO2, CeO2, TiO2). Ru/CeO2 and Ru/TiO2 with strong SMSI possess abundant electron‐deficient Ruδ+ species which exhibit a good ability to promote H2 dissociation and increase the isomerization rate of saturated aromatic compounds. Due to the enhanced adsorption of aromatic molecules, Ru/CeO2 (1.30 μmol min−1 g−1) exhibits superior catalytic activity in comparison to Ru/TiO2 (1.25 μmol min−1 g−1) during acenaphthene hydrosaturation, while Ru/TiO2 exhibits the highest isomerization reaction rate (7.60×10−2 μmol min−1 g−1) because of its excellent hydrogen spillover ability and high content of Ruδ+ species. The best catalytic activity with 96 % selectivity of ccc‐perhydroacenaphthene was achieved on Ru/TiO2, and an isomerization mechanism of perhydroacenaphthene isomers was proposed. [ABSTRACT FROM AUTHOR]

Hierarchical ZSM-5 was prepared using tetrapropylammonium bromide (TPABr) grafted multiwalled carbon nanotubes loaded with Pt as a bifunctional template for hydroconversion of soybean oil to obtain bio-jet fuel. With the increase in the grafted-TPABr-Pt loading, the deoxygenation reaction enhanced and the amount of strong acid sites and Brønsted to Lewis acid site ratio significantly increased, leading to an increase in the C4–C8 and C9–C15 fractions. Moreover, the presence of Pt in the mesoporous channels inhibited the hydrocracking reaction and enabled suitable selectivities for the C9–C15 and aromatics, in contrast to the Pt in the micropores and on the surface.

Comparative studies were conducted on physicochemical and technological properties of two black wheat (BW) varieties (cultivated in Shanxi Agricultural University) and their noodle‐making potential. Whole‐grain BW noodles showed acceptable cooking loss (≤10%) and strong antioxidant capacity. However, their textural quality remains to be enhanced. Regarding refined flour (RF) of the two BW varieties, Yunhei 14207 showed more anthocyanins, brighter color, and greater thermal stability (as reflected by the higher pasting temperature). 16W16 resulted in greater gluten content and better gluten quality of flour and higher dough stability, which contributed to the lower cooking loss and stronger tensile property of noodles. RF noodles of Yunhei 14207 displayed brighter appearance, although they had weaker tensile property. The stronger gluten network in noodles of 16W16 protected phenolics from release and degradation during drying, cooking, and steaming. Despite phenolics loss, RF noodles of Yunhei 14207 showed antioxidant capacity up to 14.97 mg TE/100 g. This research would promote understanding of characteristics of BW varieties. Considering the stronger gluten network of 16W16, its fortification in common wheat noodles at high proportion (>50%) may be promising to develop antioxidant noodles with further improved sensory quality. [ABSTRACT FROM AUTHOR]

Three kinds of Pt nanocrystals with different morphologies (5 nm cubes, 10 nm cubes and 5 nm truncated octahedrons) were synthesized and employed to fabricate Pt/CNT-USY catalysts for selective ring opening of decalin. The 5 nm truncated octahedral Pt/CNT-USY with exposed (100) and (111) facets exhibited higher yield of ring-opening products (53.9 wt%) than the CNT-USY-supported 5 nm cubic Pt catalyst enclosed by the (100) facets (39.6 wt%). Moreover, the 5 nm cubic Pt showed better catalytic activities compared to the 10 nm cubic Pt/CNT-UST catalyst, which ascribed to the smaller size of Pt NCs enriched more revealable metal active sites. DFT calculations demonstrated that the adsorption of decalin on Pt (111) was stronger than that on Pt (100) facets, which was profitable for the selective ring-opening reaction. [ABSTRACT FROM AUTHOR]