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关键词： Sweet potato starch   Cold plasma   Pullulanase   Multiscale structure   Physicochemical property  

摘要： This study explored the potential application of physical combined enzyme treatment to modify starch granules. Starch was modified by exposure to cold plasma (CP) for 1, 3, and 9 min and to pullulanase (PUL) for 12, 24, and 36 h. Individual treatments with CP and PUL somewhat modified starch structure and physicochemical prop-erties. Nevertheless, compared with native starch and individual treatments, CP-PUL combined treatment significantly (p < 0.05) promoted the subsequent structural modification, increased the short-chain ratio and the amylose content, reduce the molecular weight and the relative crystallinity, and disturb the short-range order. CP also improved the properties of PUL-modified starch, including enhanced solubility, thermal properties and resistance to enzymatic hydrolysis but worsened swelling power and peak viscosity properties. This research provides a new perspective for the rational application of CP-PUL co-treated starch in the food industry.

关键词： Viscous soluble dietary fiber   Rice starch   Physicochemical properties   Structural properties   In vitro digestibility  

摘要： The effect of carboxymethyl cellulose (CMC), high-methoxyl pectin (HMP), konjac glucomannan (KGM), and xanthan gum (XG) on the physicochemical, structural properties, and digestibility of rice starch were investigated and compared. The four viscous soluble dietary fibers (VSDFs) increased the viscosity, storage modulus and loss modulus while decreased the pasting temperature and gelatinization enthalpy. Moreover, XG produced the lowest peak viscosity and dynamic modulus compared with the other VSDFs. Furthermore, the degree of shortrange ordered structure of starch with KGM increased from 0.8448 to 0.8716;and the relative crystallinity of starch with XG increased by 12%. An ordered and reunited network structure was observed in SEM. In addition, VSDF inhibited the digestibility of rice starch and significantly increased the resistant starch content. This study compared the effect of four VSDFs on the physicochemical, structural and digestion properties of rice starch to fully understand and develop their application to starchy foods.

关键词： Gallate ionic liquid   Lubricant   Tribological property  

摘要： In this study, four kinds of GAILs were prepared and used to lubricate copper and aluminum friction counterfaces. Their physicochemical and tribological properties were systematically investigated. The results showed that the GAILs have better performances with regard to viscosity-temperature characteristic, corrosiveness and hydrolytic stability as compared with the two traditional halogen-containing IL lubricants L-B104 and L-F104. Moreover, the most prominent nature of the GAILs are their excellent friction reduction and wear resistance properties as lubricants for copper and aluminum friction counterfaces, while traditional halogen-containing ILs are generally found to be unsuitable for lubricating these counterfaces. The excellent tribological properties of the GAILs are conjectured to be largely attributed to the physical/chemical adsorbed films formed by the GAIL molecules on the friction surfaces, which is further verified by QCM and XPS analysis results. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Anthocyanin   Amphiphilic peptide   Co-assembly   Physicochemical stability   Tryptophan amino acid  

摘要： To enhance the stability of anthocyanin, an amphiphilic peptide C6 with tryptophan amino acid was used to co-assemble with anthocyanin C3G. The characterization, stabilities, and antioxidant activity of peptide-anthocyanin (C6-C3G) nanocomposites (70.82 +/- 12.41 nm) were investigated. To illustrate the interaction between peptide and anthocyanin, circular dichroism spectroscopy and fluorescence quenching method were used. Here, the peptide C6 switches from random coil structure to beta-sheet structure and the fluorescence of tryptophan amino acid in peptide quenched during the intermolecular interaction between them, which was further confirmed a static quenching. The nanocomposites significantly enhance the stabilities of anthocyanin to different alkaline conditions, high temperature of 80 degrees C, long time storage, and various concentration of Cu2+ ion. In addition, it maintained the excellent intrinsic capacity of anthocyanin to scavenge free radicals. The approach of using an amphiphilic peptide to enhance the stabilities of anthocyanin presents a high potential to expand its application.

关键词： p-coumaric acid   trans-ferulic acid   Supramolecular synthon   Hydrogen bonding   Heterosynthon   Homosynthon  

摘要： p-coumaric acid (pCA) and trans-ferulic acid (TFA) formed multicomponent crystals with 4,4'-bipyridine (BIPY) and 1,4-dioxane (DX). pCA also co-crystallised with pyridine (PYR). The crystal structures, thermal analysis, Hirshfeld surfaces and Fourier transform infrared spectroscopy of the compounds are presented. Both (pCA).(BIPY) and (TFA).(BIPY) displayed the supramolecular heterosynthons, COOH center dot center dot center dot N-pyr and OH center dot center dot center dot N-pyr. The (pCA).(DX), (TFA).(DX) and (pCA).(PYR) crystal structures featured the carboxylic acid homosynthon and the (phenol)OH center dot center dot center dot O/N heterosynthon. The observed supramolecular synthons can be related to the molecular sizes of the co-crystal formers thus allowing for the design of specific supramolecular motifs. Differential scanning calorimetry (DSC) results showed that (TFA).(BIPY) has a higher thermal stability than (pCA).(BIPY). The thermal stability of the dioxane and pyridine compounds followed the trend, (TFA). (DX) > (pCA). (DX) > (pCA). (PYR). The greater thermal stability of the TFA co-crystals can be related to the presence of the methoxy group which formed an intramolecular hydrogen bond with the hydroxyl group. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Hydrothermal carbonisation   artificial neural networks   modelling   macroalgae   hydrochar  

摘要： This study evaluates and compares several machine learning methods on the effects of different parameters in the hydrothermal carbonisation (HTC) process of macroalgae Sargassum horneri. Reaction temperature, residence time, biomass particle size, the amount of catalyst and loaded biomass were considered as inputs and three variables of BET, higher heating value (HHV) and energy recovery were regarded as outputs. For analysing the input parameters, the Taguchi method was used for experimental designs and the obtained results were utilised here as training sets. Various data mining approaches like support vector machine (SVM), group method of data handling, decision tree, random forest, radial basis function, adaptive neuro-fuzzy inference system (ANFIS) and multilayer perceptron (MLP) neural network were implemented to model the problem and two different optimisation techniques named BAT and Grasshopper Optimisation Algorithm (GOA) were employed with MLP and ANFIS model for optimising. By comparing different statistical parameters such as Average Absolute Relative Deviation (AARD), coefficient of determination (R-2), Root Mean Square Error (RMSE) and Standard Deviation (SD), It is found out that SVM method has a considerably better performance relative to other methods for estimating both the BET, HHV and energy recovery parameters. Furthermore, coupling of MLP and ANFIS with GOA increases the accuracy of these models for BET, HHV and energy recovery estimations.

关键词： Perovskite  

摘要： All inorganic perovskites CsPbX3 (X = Cl, Br, I), rising stars of optical materials, have shown promising application prospects in optoelectronic and photovoltaic fields. However, some open issues still exist in these perovskites, like poor long-term stability, inevitable intrinsic defects and much nonradiative recombination, which greatly weakens their optical capability and seriously hinders their further development. The metal doping strategy, through the partial substitution of foreign ions for native ions, has gradually become an effective method for significantly enhancing the comprehensive properties of CsPbX3. Whereas some previous studies have reported the impressive properties of metal-doped CsPbX3, there is still a lack of a comprehensive review on the influences of metal doping on CsPbX3. In this review, we aim to provide a systematic review of the latest achievements in metal-doped CsPbX3, which focuses on their synthetic methods and the positive effects of metal doping on structure, optical properties, morphology control, carrier behavior and related optoelectronic and photovoltaic devices. Finally, we put forward a few opportunities and challenges about the further investigation of metal-doped perovskites, which may help researchers explore new research directions.

关键词： Melting   Anions   Viscosity   Chemical calculations   Cations  

摘要： A simple computer tool based on MS Excel for estimating several physical, transport, and thermodynamic properties is presented. The properties included in the software are critical properties (T-c, P-c, V-c, and Z(c)), normal boiling temperature, acentric factor, density, heat capacity, thermal conductivity, viscosity, surface tension, speed of sound, melting temperature, and heat of melting. Different types of models previously proposed by the authors are used and the limitations of each model are clearly stated. These models include group contributions, semiempirical correlations, equations of state, and the geometric similitude equation of state concept. The calculations provided by the software do not aim to replace experimental data but help in obtaining a good estimate before going to the lab to experimentally measure a given property. The software is available free of charge and can be modified for particular applications.

关键词： Cream powder   nano and micron emulsion   surface fat  

摘要： The effect of fat globule sizes (0.21, 0.75, and 1.41 mu m) on the properties of dairy cream powder was investigated at different fat contents (35, 45, 55, and 70% (w/w solids)). The cream powder produced from nano-sized cream emulsions had the lowest surface fat content among all fat globule sizes. The lowest surface fat content (1.8% w/w) was observed in 35% fat containing powder prepared from emulsion with average fat globule size of 0.21 mu m. Confocal laser scanning microscopy and X-ray photoelectron spectroscopy results also supported the results of the free fat content determined by the solvent extraction method.

关键词： Infant formula powders   lactose crystallinity   surface morphology   surface fat   caking  

摘要： Shelf life of infant milk formula (IMF) powders depends on product composition and storage environment. We produced model IMF powders by mimicking human milk and investigated the effects of storage conditions on surface characteristics and caking behavior of these powders. The powders were stored for 21 days at two different temperatures (25 degrees C and 45 degrees C) and three relative humidity (RH) levels (11%, 44%, and 85%). The storage of these powders at higher RH, higher temperature, or their combinations increased lactose crystallinity, increased surface fat content, altered surface chemical composition, and induced caking. The powders stored at 45 degrees C and 85% RH had highest lactose crystallinity and fat content on the surface. The increase in crystallinity and surface free fat also increased the caking strength. Storage at ambient temperature (25 degrees C) and low RH levels (11% and 44%) was found to avoid lactose crystallization and caking. These findings will help manufacturers and consumers to implement suitable storage protocols that would help extend shelf life of IMF powders.