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关键词： Sensory attributes   consumer likeness   Young's modulus   bread staling   PCA  

摘要： The aim of this work was to evaluate the physicochemical and sensory characteristics of sliced pan breads and to investigate their possible correlation. Five commercial sliced pan breads from different brands (C1-C5) were examined for four weeks. A two-way ANOVA revealed significant differences in the moisture content, Young's modulus and mean cell area among the different brands. Principal Component Analysis showed a good agreement between sensory and instrumental measurements. MaxDiff analysis revealed that the sliced pan bread of the brand C1 is considered as the most favored bread by the consumers whereas the bread of brand C2 as the least favored one.

关键词： 物理化学   独立移动定律   概念形成策略   学习兴趣  

摘要： 物理化学是化学学科的一门基础理论课,其课程公式多、抽象概念多、理论性强、系统性强、逻辑性强,在学习的过程中学生普遍存在畏难情绪,不利于知识系统化学习和掌握。本文基于以上特点,以概念形成策略进行离子独立移动定律的教学设计为例,引导学生去伪存真,把握事物的本质形成正确概念并且调动学生对物理化学的学习兴趣,不断探索和实践。

关键词： 物理化学   稀溶液的依数性   PBL教学模式   LBL教学模式  

摘要： 理工科《物理化学》课程的学习,往往课时紧难度大,学生学习积极性不够,且枯燥难懂。如何提高课堂教学质量和教学效果,显得尤为重要。本文通过"稀溶液的依数性"的教学为例,建议在《物理化学》课程的讲授中,采用PBL联合LBL的双轨教学模式,充分调动学生学习的积极性,培养学生自主学习和终身学习的能力。

关键词： 拟薄水铝石   焙烧温度   物理化学性质  

摘要： 将工业级粉状拟薄水铝石再成型后,用不同的焙烧温度焙烧,制得柱状载体。通过XRD、NH3-TPD、BET等表征手段,对样品进行表征。结果表明焙烧温度对该氧化铝载体的晶型、表面酸性、孔容、孔道、比表面积等物理化学性质均产生不同程度的影响。

关键词： Mango butter   Polyglycerol polyricinoleate   Crystallization kinetics   Crystal behavior  

摘要： Emulsifiers act as Fat crystal modifiers and can modulate the crystallization process of fats. In this study, we have reported the effect of polyglycerol polyricinoleate (PGPR) on the physicochemical properties of an underutilized vegetable fat "mango butter" (MB). MB-PGPR based formulations were prepared by heat-cool method. Microscopic studies showed that PGPR resulted in the formation of globular MB crystals. XRD and thermal studies conjointly suggested that the MB crystals were predominantly crystallized as beta-polymorph. However, PGPR induced imperfections within the MB crystals. FTIR spectroscopy revealed that PGPR considerably varied the local environment of the MB crystals. PGPR also altered the nucleation time and crystallization rate of the MB crystal formation. The MB formulation that contained 2.5% (w/w) PGPR was found to have good mechanical stability. In gist, the addition of PGPR (as a crystal modifier) can help us to influence the crystal behavior and physicochemical properties of the MB fat.

关键词： 材料物理化学   思维导图   合作性学习   多元化考核   教学改革  

摘要： 《材料物理化学》是材料科学与工程专业必修的基础理论课程,也是比较难学的一门课程。针对该课程的特点,论文从教学方法和考核方式两大方面提出了具体改革措施,同时阐明了这些措施在教学过程中的意义。通过教学改革能够激发学生的学习兴趣,培养学生的创新思维和综合素质,也能更加全面而客观地评价学生的综合能力,有利于进一步提升教学水平。

关键词： 物理化学   教学改革   知识体系构建   自我展现   交互式教学  

摘要： 针对物理化学学科特点和学生在物理化学课程学习中存在的问题,结合3年物理化学教学经验,介绍了师生交互式课堂教学改革的成效。通过重视知识体系架构的建设,增加交互式、案例式、故事性教学和自我展现环节等教学方式改革和实践,丰富了课堂形式,增强师生互动,提升学生的课堂参与率和学习热情,增加学习趣味性和效率,值得进一步推广和示范。

关键词： Wetting  

摘要： Abstract: Analytical electron (SEM-EDX) and confocal laser scanning microscopy (CLSM), microhardness testing, determining the contact angle of wetting, and other means are used to study the mechanism behind changes in the structural state of surfaces, and the mechanical, physicochemical, and technological properties of semiconductor ore minerals (sulfides) and natural quartz under conditions of a pulsed dielectric barrier discharge at atmospheric pressure in air. Due to the action of the products of low-temperature plasma and other effective factors resulting from a discharge, the minerals soften (general maximum relative reduction in microhardness ~730%), and the morphology, roughness, contact angle of wetting of the surfaces of mineral polished sections, and the flotation activity of sulfide minerals change with respect to the duration of plasma treatment. © 2020, Allerton Press, Inc.

关键词： Higher fatty acid starch ester   Extrusion   Starch ester film   Phytotoxicity   Biodegradability  

摘要： Medium-substituted esters of starch and higher fatty acids, structurally identified in the first part of paper were subjected to further analyses, mainly to check application potential. In order to determine the possibility of using the esters in the packaging industry, the glycerol-plasticized starch esters were extruded on a single screw extruder in the form of a film. The mechanical properties tests consisted of tensile and tear strength. Hydrophobicity, water absorption and oil absorption were checked as the processing and functional properties. Environmental tests, such as phytotoxicity on monocotyledonous and dicotyledonous plants and biodegradability in soil under strictly controlled conditions of the vegetation hall were carried out. Esterification increased the hydrophobicity of the starch and the tensile and tear strength, without losing important environmental features such as biodegradability and non-toxicity. The obtained polymer materials give hope for their use in the production of new ecofriendly and biodegradable packaging.

关键词： Physicochemical properties  

摘要： Abstract: The mechanism of change in the structurally sensitive surface characteristics and physicochemical properties of rare-metal minerals (columbite and eudialyte) as a result of exposure to low-temperature atmospheric-pressure plasma is studied by means of DRIFT, analytical electron (SEM) and atomic force (AFM) microscopy, and measuring microhardness, electrokinetic potential, and angles of wetting. Results demonstrate the fundamental possibility of using low-temperature plasma to improve the efficiency of softening and altering the structural and chemical properties, surface hydrophobicity, and sorption activity of rare-metal minerals. © 2020, Allerton Press, Inc.