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关键词： 线上教学   物理化学   实践   过程性评价  

摘要： 在全球新型冠状病毒肺炎疫情持续蔓延的时代背景下,各大高校的线上教学活动已经成为时代发展的迫切需要。文章以上海中医药大学的物理化学课程为例,结合本学年刚完成的线上教学实践,介绍物理化学线上教学的课程准备、过程设计与实施情况,并探讨分析目前该课程线上教学的教学特点与教学效果,以期优化改革其线上教学质量,为后续线上教学的发展提供一定的借鉴。

关键词： 课程思政   冶金物理化学   教学改革  

摘要： 立德树人是教育的根本任务,专业课是高校实现“三全育人”教育目标的重要载体。冶金物理化学作为一门重要的专业基础课,开展课程思政十分必要。通过课程内容里思政元素的挖掘以及授课模式的革新等方面探索思想政治教育融入冶金物理化学课程的有效途径。

关键词： Taro (Colocasia esculenta)   Response surface methodology   Water-soluble non-starch polysaccharide   Improved conventional extraction   Freeze-thaw  

摘要： This study investigated the effects of an improved extraction method that utilized freeze-thaw, termed improved conventional extraction (ICE), on the yield and properties of the water-soluble non-starch polysaccharide of taro (Tc-WS-NSP) and compared this method to the conventional extraction (CE) method. The freeze-thaw condition was optimized using response surface methodology (RSM) based on yield. The use of the ICE method resulted in a 227.8% increase in yield of Tc-WS-NSP compared to the CE method. The Tc-WS-NSP-ICE had higher purity, lighter color, larger particle size, and higher zeta-potential than Tc-WS-NSP-CE. Both of the samples contain the sugar arabinose, galactose, glucose, and mannose and exhibited comparative FTIR, H-1, and C-13 NMR spectra. The Tc-WS-NSP-ICE had a semi-crystalline structure resulting in higher thermal stability and had a higher consistency index than Tc-WS-NSP-CE. Overall, the use of the ICE method provided a simple, efficient, and green alternative to CE for the extraction of Tc-WS-NSP.

关键词： 物理化学   思想政治教育   原子簇化学   稀土分离技术   水的三相点   分子立体结构理论  

摘要： 大学物理化学是一门逻辑性、理论性及系统性较强的交叉学科,由于公式多、概念多及计算量大,学生普遍反映学习难度较大。如何将课程思政润物细无声地渗透于理论知识中,在激发学生学习兴趣的同时,帮助他们树立正确的价值观、社会观及远大的人生理想是值得研究的。本文探索了大学物理化学课程与思想政治教育相结合的方式,将思政教育与大学物理化学基本原理融于各位科学家创作的趣味性故事中,是一次有意义的探索与实践。

关键词： 1-Octyl-1-methylpyrrolidinium bromide   Amino acid and glycyl dipeptide   Solute-solvent interaction   Thermodynamic parameters  

摘要： The conductivity and density of aqueous solution containing ionic liquid (1-octyl-1-methylpyrrolidinium bromide, [C(8)C(1)Pyrr]Br) and amino acid/glycyl dipeptide have been measured at various temperatures. Additionally, the spectroscopy studies were also carried out. Electrical conductivity and fluorescence spectroscopy data were utilized to calculate critical micelle concentration, cmc at T = (288.15-308.15) K and aggregation number, N-agg of [C(8)C(1)Pyrr]Br, respectively. Based on the obtained cmc values, the thermodynamic quantities i.e. Gibbs energy change, enthalpy change, and entropy change of micellization are evaluated. From the measured density, some derived properties like apparent molar volume at infinite dilution, transfer volume, hydration number and apparent molar expansibility at infinite dilution of amino acid/glycyl dipeptide in [C(8)C(1)Pyrr]Br solutions were determined. Binding constants between [C(8)C(1)Pyrr]Br and amino acid/dipeptide were derived from UV-vis spectroscopic data. The gotten properties were discussed based on the molecular interactions and structural changes present in the studied ternary systems. (C) 2021 Elsevier Ltd.

关键词： Chocolate spread   Hazelnut cake   Optimization   Mixture design  

摘要： The purpose of the current study was to evaluate the impact of hazelnut cake as a partial replacer for sugar, milk and whey powders on the chocolate spread. A D-optimal mixture design was used to determine the effect of different mixtures of sugar, total milk originated powders (MOP), as milk powder and whey powder, and hazelnut cake (HC) on the physicochemical properties, as well as in vitro digestion of total phenolic compound before and after digestion and its bioaccessibility. Results were described by appropriate mathematical models defined by using best-fitting analysis. According to the results, the fitted models illustrated a desirable coefficient of determination (>= 81%). The optimization of the variables indicated that using 43.562% sugar, 7.186% MOP and 7.252% HC produced the optimum chocolate spread with the highest desirability (1.00) without unwanted variations in the quality properties. The HC as an industrial by-product could be used in chocolate spread to increase bioactive compounds and also to decrease product costs by decreasing the sugar, milk and whey powder of the final product.

关键词： catfish byproducts   denaturation   pH   protein isolate   protein recovery   texture  

摘要： In order to optimize protein recovery from catfish byproducts by alkaline extraction, the effects of different factors, including particle size, mince-to-water ratio, pH, and extraction time were investigated. It was found that a protein recovery of about 30% could be achieved. Increases in pH (pH 10.5, 11, and 11.5) not only improved protein recovery, but also increased protein denaturation evidenced by decreased solubility, decreased alpha-helix, increased beta-sheet, and increased random coil. The color and texture of gels made from protein isolate were greatly affected by the pH values used for protein extraction. For the gels made from fillet mince, and protein isolates extracted at pH 10.5, 11, and 11.5, the "L" values were 78.96, 60.38, 57.74, and 54.39, the breaking forces were 205, 492, 585, and 458 g, and deformation values were 10.59, 8.07, 6.73, and 5.04 mm, respectively. Electrophoresis revealed protein degradation during alkali-aided extraction with MHC, the most predominant band, showing about 50% decrease in comparison with fillet mince. It also demonstrated that gelation not only caused cross-linking, but also autolysis with 53%, 56%, 59%, and 81% decrease in MHC intensity for fillet mince, protein isolates extracted at pH 10.5, 11, and 11.5, respectively. Fillet mince and protein isolates exhibited different storage modulus patterns during temperature sweep, implying different gelation mechanisms. This study proved the protein extracted from catfish byproducts was potential to be utilized as edible food components especially in gel making. Practical Application Catfish byproducts, which account for 70% of total weight and 50% of total protein of catfish, are normally used as animal feed, fertilizer, or even waste. This study demonstrated the potential of the utilization of catfish wastes to develop edible food components. This could reduce the total processing waste being discarded into the environment and nutrient loss, therefore increasing profit

关键词： Red seaweed   Chondracantus canaliculatus   Carrageenan   Ultrasound extraction   Physicochemical properties  

摘要： Red seaweed Chondracanthus canaliculatus, an underexploited algae species, was used as a potential source for the obtaining of carrageenan. Seaweed was treated under alkaline conditions using ultrasound alone or combined with conventional procedures, to improve the yield extraction. Color, syneresis behavior, water retention capacity, and functional groups of the gelling and non-gelling fractions of carrageenan were determined;these properties were compared with those of commercial carrageenans named A and B. Ultrasound alone or with heat significantly (p < 0.05) increased the yield extraction up to 41-45% and influenced color parameters, in comparison with conventional treatments. Functional groups kappa and iota, and alginates, were confirmed in both carrageenan fractions. Syneresis behavior was well fitted to a third-degree polynomial equation within days 1 to 6, after which, it reached a plateau. While, the use of ultrasound at room temperature gave carrageenan properties more similar to those of the commercial carrageenan type A.

关键词： Luminance  

摘要： Corn grits were extruded then extrudates were expanded by microwave-heating. Effects of addition of xanthan gum (XG) (0%-1%), feed moisture content (37%-47%) and screw speed (100-300 rpm) level on physicochemical properties of snacks were evaluated with response surface methodology (RSM). All suspensions of expanded samples exhibited shear-thinning behavior. Apparent amylose content of samples ranged from 22.47% to 37.97%. Screw speed and feed moisture content had positive effect on apparent viscosity and amylose content but XG level had negative effect on them. Increasing screw speed increased expansion and luminosity but decreased browning index and total color difference. Increasing feed moisture content resulted in reduced expansion, luminosity but increased browning index. In contrast to the initial effect, expansion and browning index decreased when XG addition level was above 0.5%. Optimum conditions were determined to obtain the maximum values for expansion index and luminosity and minimum value for the total color difference by desirability function. They were found as 300-rpm screw speed, 47% feed moisture content and 0.34% XG level. Practical applications Extrusion process occupies an important place in the food industry for production of snacks and breakfast cereals. This technology is especially preferred due to its versatility, high productivity, relative low cost energy efficiency for snack production. However, extrusion process conditions (feed moisture, screw speed, and barrel temperature) and additives used in this process have critical importance for snack characteristics. Gum addition provides lubrication during extrusion process. Expansion and color characteristics of product may be change according to gum addition level. Response surface methodology (RSM) can be used as an optimization tool to achieve a better product considering multiple quality characteristics for snacks. A better evaluation of simultaneous interactive effects of process vari

关键词： Navy bean   Flours   Functionality   Starch digestibility   Protein quality  

摘要： Physicochemical, functional, and nutritional properties of flours from six navy bean varieties cultivated in two different locations in Manitoba, Canada were evaluated. The effect of genotype was found insignificant for protein content, ash content, zeta potential, and surface hydrophobicity among physicochemical properties (p > 0.05). For protein content, total starch content, and zeta potential of navy bean flours, environmental factors were found significant (p < 0.05). Genotype, environment, and genotype x environmental interactions were determined as significant for water holding capacity as well as for trough and final viscosities of flours. There was no significant effect on the pasting temperature of flours (p > 0.05). In vitro protein digestibility results varied by genotype. Although in vitro protein digestibility corrected amino acid score values were significantly affected by genotype, environment, and their interactions similar to slowly digestible starch. The current study established a better understanding of the varietal effects of genotype and environment on a wide range of properties of navy bean flours.