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旨在为制备不同风味品质的菜籽油提供理论依据，通过感官风味品质评价、电子鼻分析、顶空固相微萃取气相色谱-质谱联用技术（HS-SPME-GC×GC/MS）等手段，研究了微波处理对菜籽油风味的影响。结果表明：微波能输入总量和输入强度均影响菜籽油感官风味品质；电子鼻分析结果表明，浓香菜籽油与非浓香菜籽油的挥发性风味成分具有相似性;非浓香菜籽油主要风味物质有23种，包含醛类物质7种、硫类物质5种、醇类物质3种、酸类物质2种、酯类物质2种、杂环类物质2种、烯烃类和酚类物质各1种，为非浓香菜籽油提供辛辣味、脂香味、青草味和花香味等风味；浓香菜籽油中主要风味物质有13种，包含硫类物质5种、杂环类物质3种、醛类物质2种以及酚类、醇类和酸类物质各1种，主要赋予浓香菜籽油辛辣味、烤香味、焙烤味和脂香味等风味。综上，微波预处理技术对菜籽油的风味有显著影响，随着微波能的输入，菜籽油风味由主要以硫苷降解物和氧化挥发物为主导的辛辣味、脂香味、青草味、花香味，转变为以硫苷降解物、美拉德反应产物和氧化挥发物为主导的辛辣味、烤香味、焙烤味和脂香味。Aiming to provide a theoretical basis for the preparation of rapeseed oil with different flavor qualities, the effect of microwave treatment on the flavor of rapeseed oil was investigated by means of sensory flavor quality evaluation, electronic nose analysis, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS - SPME - GC×GC/MS). The results showed that the total amount and intensity of microwave energy input affected the sensory flavor quality of rapaseed oil. The electronic nose results showed that the flavor components of fragrant rapeseed oil and non-fragrant rapeseed oil were similar. There were 23 main flavor substances in non-fragrant rapeseed oil, including 7 aldehydes, 5 sulphur substances, 3 alcohols, 2 acids, 2 esters, 2 heterocyclics and 1 each of olefins and phenols, which provided pungent, oily, grassy and floral flavors to non-fragrant rapeseed oil. There were 13 main flavor substances in fragrant rapeseed oil, including 5 sulphur substances, 3 heterocyclics, 2 aldehydes, and 1 each of phenols, alcohols and acids, which mainly gave fragrant rapeseed oil pungent, roasted, bakery and oily flavors. In conclusion, microwave pretreatment technology has a significant effect on the flavor of rapeseed oil. With the input of microwave energy, the flavor of rapeseed oil mainly changes from pungent, oily, grassy and floral flavors dominated by thioglycoside degradation products and oxidized volatiles to pungent, roasted, bakery and oily flavors, dominated by the products of the thioglycoside degradation products Maillard reaction products and oxidized volatiles.

Owing to its higher earth element reserve and similar chemical properties to lithium, potassium ion batteries (PIBs) have been regarded as a potential alternative to lithium-ion batteries. And considering the relatively larger ionic radius of potassium, available electrode materials need to be equipped with enough space for volume expansion during charge–discharge cycles, thus graphitic carbon nanomaterials with adjustable layer spacing gradually come into researcher's version. Here with copper nanowires serving as growth template and organic polyvinyl pyrrolidone (PVP) providing carbon source, freestanding and ultra-light graphitic carbon nanotube (GCNT) aerogels were simply assembled and annealed, which were directly used as anodes of PIBs. Annealing parameters (temperature and atmosphere) were adapted to regulate the lattice order and interlayer spacing of GCNTs, and N, O heteroatoms derived from PVP were directly doped into the carbon lattice during thermal annealing, to optimize and enhance the cycle capacity and rate performance of GCNT anodes. The electrochemical potassium storage mechanism of GCNTs was also quantitatively analyzed. Most of the potassium ions are reversibly stored by squeezing into and escaping from the carbon lattice, and simultaneously oxygen-containing functional groups with different chemical states also offer active redox sites and dedicate partial capacity. Therefore, our assembled GCNTs with large lumen are expected to sandwich-like load with active substances efficiently, further constructing next-generation PIBs with excellent performance. [ABSTRACT FROM AUTHOR]

This work attempts to achieve the enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in acylglycerols as well as biodiesel production by investigating the performance of various lipases in ethanolysis. The ethanolysis activities of five immobilized lipases in decreasing order were as follows: Lipozyme TL IM, Novozym 40086/Lipozyme RM IM, Novozym 435 and Rhizopus oryzae lipase immobilized on polypropylene (RO PP). EPA could be enriched to a certain content by Lipozyme TL IM, Novozym 40086, Lipozyme RM IM, and RO PP. The enrichment of DHA was achieved well by those four sn‐1,3 regioselective lipases, and DHA contents in acylglycerols were the highest when Lipozyme TL IM and Novozym 40086 were used, reaching 2.87‐fold and 2.81‐fold of the initial content. However, Novozym 435 could not enrich EPA and DHA effectively. Fatty acid ethyl esters produced in this work contained abundant palmitic acid and palmitoleic acid, which could be ideal biodiesel considering their chain length. The competitive factors of five lipases towards DHA were all significantly higher than those towards EPA. When Lipozyme TL IM and Novozym 40086 achieved the maximum DHA contents, their DHA recoveries in acylglycerols reached 91.87% and 89.00%, respectively. The DHA recoveries were all significantly higher than the corresponding EPA recoveries in the reactions catalyzed by five lipases. Moreover, Lipozyme TL IM could be a potential lipase for the separation of EPA and DHA. This study may promote the full use of fish oil and broaden the application of lipases. [ABSTRACT FROM AUTHOR]

Coulombic efficiency (CE) and rate capability are crucial parameters for advanced secondary batteries. Herein, for the first time, we report controllable amorphization and morphology engineering on mixed-valence Fe(II , III)-MOFs from the crystalline to amorphous state and micro-clustered to hollow nano-spherical geometry through valence manipulation by a dissolved oxygen-mediated pathway. The disordered structure and the hollow nanostructure can endow the MOFs with the highest initial CE (>80%) to date for MOF electrodes, and ultrafast and super-stable near-pseudocapacitance lithium storage. These findings can provide new ideas for the engineering of MOF systems for application in LIBs. [ABSTRACT FROM AUTHOR]

Fucoxanthin is a carotenoid, reddish-brown in color, which is mainly derived from marine organisms such as brown algae and diatoms, and has aroused extensive scientific interest due to its unique chemical structure and abundant biological activities. Studies have shown that fucoxanthin processes significant anti-inflammatory and anti-cancer activities. Its anti-inflammatory mechanisms primarily include inhibiting oxidative stress, regulating inflammatory factors, inducting cell autophagy, and resisting cell apoptosis, etc. The main mechanism of anti-cancer activity includes inducing cell autophagy and apoptosis mechanisms, regulating the cell cycle, inhibiting cell migration, and suppressing cell invasion, among other aspects. In this paper, the research progress of anti-inflammatory and anti-cancer activities and related mechanisms of action of fucoxanthin is briefly summarized, which provides the theoretical basis and reference for further research and development of fucoxanthin. [ABSTRACT FROM AUTHOR]

In this paper, BiOBr nanosheets were synthesized through a novel hydrolysis precipitation method, which significantly reduced energy consumption and time cost compared to traditional hydrothermal synthesis methods. The subjected hydrothermal and high‐temperature calcination process promote the generation of surface oxygen vacancies, which inhibited the recombination of photogenerated electron hole pairs and improve the photocatalytic performance of BiOBr. Additionally, by adjusting the addition amount of KOH in the synthesis process, BiOBr can grow towards more complex crystal structure, which also provides a new path for the fabrication of 2D materials. [ABSTRACT FROM AUTHOR]