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关键词： 物理化学   思政元素   翻转课堂  

摘要： 物理化学是基于量子力学结论,应用数学的方法和思想来研究化学变化和物理变化现象之间关系的一门课程分支。该课程具有公式多,概念抽象,方法性强三大特点。结合物理化学课程的特点,借助多种教学方式,积极探索蕴含在该课程中的思政元素,提高学生的学习积极性,活跃课堂气氛,培养学生的创新能力,变"要我学"为"我要学",最终实现学生思想道德建设,创新能力和知识储备全面提升。

关键词： 土力学   环境荷载   物理化学   NaCl溶液   有效应力   体变  

摘要： 盐溶液浓度变化对土体变形行为的影响是环境及能源岩土工程中的一个重要科学问题。为了实现饱和黏土在外荷载作用下以及孔隙盐溶液浓度变化条件下体变行为的定量化描述,基于考虑土颗粒间物理化学作用的粒间应力方程,建立考虑孔隙盐溶液浓度影响的饱和黏土统一压缩模型。采用不同孔隙盐溶液浓度下高庙子膨润土的固结试验数据验证了统一压缩模型的存在性。应用该统一压缩模型进行了饱和黏土在不同上覆应力下的盐溶液浓度增加路径,盐溶液浓度-外荷载耦合加载路径的计算。计算结果与试验结果的对比表明,建立的统一压缩模型能够较好的描述不同孔隙盐溶液浓度作用下饱和黏土的变形特性。进而验证了建立的统一压缩模型的正确性。

关键词： Stingless bee honey   Physicochemical properties   Volatile compounds profiling   Chemometrics and machine learning   Discrimination   Chemical markers  

摘要： Identification of honey origin based on specific chemical markers is important for honey authentication. This study is aimed to differentiate Malaysian stingless bee honey from different entomological origins (Heterotrigona bakeri, Geniotrigona thoracica and Tetrigona binghami) based on physicochemical properties (pH, moisture content, ash, total soluble solid and electrical conductivity) and volatile compound profiles. The discrimination pattern of 75 honey samples was observed using Principal Component Analysis (PCA), Hierarchical Clustering Analysis (HCA), Partial Least Square-Discriminant Analysis (PLS-DA), and Support Vector Machine (SVM). The profiles of H. bakeri and G. thoracica honey were close to each other, but clearly separated from T. binghami honey, consistent with their phylogenetic relationship. T. binghami honey is marked by significantly higher electrical conductivity, moisture and ash content, and high abundance of 2,6,6-trimethyl-1-cyclohexene-1-carboxaldehyde, 2,6,6-trimethyl-1-cyclohexene-1-acetaldehyde and ethyl 2-(5-methyl-5-vinyltetrahydrofuran-2-yl)propan-2-yl carbonate. Copaene was proposed as chemical marker for G. thoracica honey. The potential of different parameters that aid in honey authentication was highlighted.

关键词： 表面张力   接触角   量子化学计算   分子动力学模拟  

摘要： 文章采用铂金板法、静滴接触角量角法对胺类阳离子捕收剂的表面张力和接触角进行测定;采用Origin软件对数据进行处理并进一步计算临界胶束浓度(CMC)、分子横截面积和粘附功等;采用Material Studio 8.0软件进行建模,并分别使用Dmol3模块、Forcite模块对药剂和矿物进行结构优化、量子化学计算、分子动力学模拟等。该综合实验将表面物理化学实验与浮选药剂结构及性能判据的理论知识有效结合,在锻炼学生实验动手能力的同时,能够培养学生在药剂浮选机理研究中的科学思维与分析能力。

关键词： 材料物理化学   思政教育   教学改革   本科教育   材料化学  

摘要： 高校教师在工作中应时刻坚持以“立德树人”为教学目标。《材料物理化学》作为我校材料化学专业的必修课程,对本科生专业素质的培养起着重要作用。教师在传授书本知识的同时,还应意识到对学生进行思政教育的重要性。本文从课程的学习内容出发,结合我国思政教育的方针政策,深入挖掘课程中所包含的思政元素,以期为相关专业教师的课程思政教改提供参考思路。

关键词： 物理化学   一流专业   线上线下融合教学   教学改革  

摘要： 物理化学课程有着概念公式多、逻辑性强及抽象难以理解的特点,本文在互联网迅速发展的背景下,对物理化学课程线上线下融合教学模式的实践和探索进行了总结,希望能对该课程的教学改革提供一定的参考,进而达到提升其教学质量的目的。

关键词： Pear cold storage   Nitric oxide donor   Respiration rate   Sensory quality   Enzyme activity  

摘要： Quality loss in pear fruit during storage reduces its marketability for long run. To increase its storability, the efficacy of postharvest dip treatment donor sodium nitroprusside (SNP) 0.000, 0.001, 0.002 and 0.003 mol L-1 were investigated on pear fruit cv. Patharnakh under storage conditions (low temperature 0-1 degrees C and relative humidity (90-95%). SNP effectively lowered fruit mass loss, retained colour and higher firmness, suppressed browning and respiration rate and sustained soluble solids content, titratable acidity, total phenol content and ascorbic acid thus conserved the fruit quality for longer period. SNP treatments suppressed the activity of polyphenol oxidase and increased activity of superoxide dismutase enzyme. Additionally, the SNP treated fruit exhibited lesser activities of fruit softening enzymes like pectin methylesterase, polygalacturonase and cellulase. Among all, 0.002 mol L-1 SNP concentration was superior to lengthen storability and sensory quality of pear up to 60 d under cold storage.

关键词： Cactaceae   Chemical composition   Arabinogalactan   Mandacaru   Xique-xique   Facheiro  

摘要： Brazilian cacti have the high potential to be used as a source of mucilages with different technological functions that can be widely explored. The physicochemical, structural and technological properties of mucilages extracted from seven cladodes of cacti native from the semi-arid region of the Brazil were investigated. The mucilages exhibited high yields (8.9 to 21.54%), high contents of carbohydrates (39.77 to 87.68%), proteins (4.27 to 14.76%), and minerals, specifically Ca (2.90 to 15.65%). All species evaluated presented a diverse monosaccharide composition, mainly constituted of galactose and arabinose, suggesting the presence of arabinogalactans as the main polysaccharides. Both showed peaks and bands characteristic of polysaccharides with semicrystalline structure (14.50-38.60%), due to the high concentration of calcium. From the results, mucilages functional properties showed good water and oil retention capacities and a high emulsification capacity (100%) with stability above 83%. Foaming capacity was above 58% with stability greater than 95%. This study highlights the potential of using cacti as a source of functional mucilages for use in food applications.

关键词： 金属光泽   元素周期表   稀散元素   元素符号   克鲁克斯   物理化学   延展性   原子序数  

摘要： 铊是由英国物理化学家威廉·克鲁克斯于1861年从10磅含硒的硫酸产品废液中提取碲时发现的。铊的属性铊位于元素周期表中第六周期第Ⅲ主族,原子序数为81,元素符号为Tl。在自然界中,铊有两个稳定的同位素:铊205和铊203。铊的熔点为303.5℃,沸点则为(1457±10)℃,是一种银白色金属,柔软并具延展性,用指甲可以刻痕,并能在纸上画出黑色的线条,其断面有强烈的金属光泽。

关键词： 思想政治教育   “物理化学”   课程思政   教学改革  

摘要： 课程思政的提出,其目的是构建全员、全过程、全课程的育人格局,是将思想政治教育与各类课程进行有机结合,形成协同效应。以开展课程思政为契机,探究了“物理化学”课程思政的意义,并将社会主义核心价值观的思想教育和中华优秀传统文化的情感教育作为该课程的思想政治目标。同时,把民族使命感和自豪感、爱国热情和社会责任感以及礼仪文化等思想政治元素融入课程设计和课堂教学过程中,以促进课程思政建设和增强课程思政实效,从而提升教学效果和人才培养质量。