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关键词： 亨利定律   摩尔浓度   气体分压   英国化学家   基本定律   物理化学   溶解度  

摘要： 亨利定律,是物理化学的基本定律之一。是由英国化学家威廉:亨利在1803年研究气体在液体中的溶解度规律时所发现的一个气体的定律。可表述为在常温下且密闭的容器中,溶于某溶剂的某气体之体积摩尔浓度,会正好与此溶液达成平衡的气体分压成正比。

关键词： 物理化学   状态函数   大道至简   教学方法  

摘要： 物理化学是化学学科的理论基础,其中化学热力学、化学动力学、量子力学以及统计热力学是构成物理化学的四大基础。物理化学涉及到很多抽象的概念、理论以及复杂的公式推导等。本文以状态函数为例,通过简单形象的类比,帮助学生判断状态函数的强度性质和广度性质,教学效果良好。故此,物理化学教学过程中“大道至简”的教学方法应高度重视和积极提倡。

关键词： 亨利定律   摩尔浓度   气体分压   英国化学家   基本定律   物理化学   溶解度  

摘要： 亨利定律,是物理化学的基本定律之一。是由英国化学家威廉·亨利在1803年研究气体在液体中的溶解度规律时所发现的一个气体的定律。可表述为在常温下且密闭的容器中,溶于某溶剂的某气体之体积摩尔浓度,会正好与此溶液达成平衡的气体分压成正比。亨利定律的公式为。

关键词： 化学教学   表面化学   课程建设   创新发展   协调发展  

摘要： 以开尔文公式为例,探讨新发展理念在物理化学教学中的应用,把创新、协调、绿色、开放、共享的新发展理念贯穿到物理化学教学的全过程和各章节并通过教学设计展示,以促进物理化学课程的高质量发展,加快新时代物理化学课程建设的新格局,贯穿落实新发展理念,对化学、理学乃至整个高等教育的发展具有示范作用。

关键词： 课程思政   物理化学   资源发掘   有效实施  

摘要： 课程思政建设是当前加强高校思想政治工作和专业课程教学改革的重要内容。本文结合物理化学课程思政实践,提出实施课程思政要把握“身正示范、把握涵义、隐性教育”三原则,按照思政教育七个目标,通过基本理论知识、公式推导与结论证明、理论知识应用、中国物理化学家的贡献、优秀传统文化、学科交叉融合、科学家故事等挖掘思政元素,培养辩证唯物主义观、学科思维、创新思维、审辨能力、家国情怀、人文素养、社会责任感与使命感,为理工科课程思政教学提供了有益参考。

关键词： 物理化学   自主学习能力   教学方法  

摘要： 物理化学是一门理论性很强的课程。随着网络的普及,教育与现代信息技术的不断融合发展改变了传统的教学理念和教学模式,自主学习能力成为获取知识和信息不可或缺的技能。本文结合物理化学教学和网上课程的建设,对以提升大学生自主学习能力为目标的教学方法和模式进行了研究和探讨。

关键词： Salted vegetable   Dry salting   Brine pickling   Flavour profile   Bacterial community  

摘要： The profiling of physicochemical properties, nonvolatile flavour compounds and bacterial community during the fermentation of Chinese dry-salted and brine-pickled radishes was performed. Dry-salted radishes matured on the 30th day, and the pH, total titratable acid, and water activity of the matured samples were 4.7, 0.43 g/100 g lactic acid, and 0.90, respectively. Brine-pickled radishes matured in only 5 days, and the pH, total titratable acid, and water activity were 3.4, 0.31 g/100 g lactic acid, and 0.96, respectively. The contents of reducing sugars, organic acids, and free amino acids generally increased with the fermentation of dry-salted radishes, reaching 15.8 g/100 g, 1009.1 mg/100 g, and 300.3 mg/100 g on the 30th day, respectively. Lactic acid was the characteristic flavour substance of brine-pickled radishes. Exiguobacterium, Glutamicibacter, and Leuconostoc were the dominant genera when the dry-salted radishes matured. Lactobacillus dominated brine-pickled radish fermentation and was correlated to lactic acid, Arg, Val, and His (P<0.05). This study could improve our understanding of the effects of dry salting and brine pickling on the flavour and bacterial characteristics of salted vegetables.

关键词： COVID-19   表界面化学   解读   科学研究   知识点  

摘要： 以表界面物理化学的视角看待和解读抗疫科研成果,充分挖掘生命健康,讨论新冠疫情事件中的病毒检测和传播、护目镜起雾及口罩防护涉及到的知识点,结合物理化学6个章节中的热力学第一和第二定律、胶体化学、表面化学、相平衡和溶液等内容来理解。抽象概念和理论与现实抗疫元素的有机结合,使学生能够学以致用。

关键词： Biomass   Activated biochar   Activation methods   Impregnation techniques   Water purification  

摘要： The biochar produced from agricultural crop residues through thermochemical processes helps in crop waste management. Biochar has paid more attention due to its distinctive features such as high organic carbon content, stable structure, large surface area, and cation exchange capacity. The biochar obtained from crop residues can be readily converted into activated biochar. This review paper systematically summarised the preparation of activated biochar, characterisation, and analytical techniques of activated biochar based on more than 150 literatures published in the last 10 years. The physicochemical properties of activated biochar varies according to the type of feedstock, pyrolysis condition, and mode of activation. The selection of the activation method mainly depends on its further end environmental application. Physical activation or steam purging at high temperature creates pores inside biochar. Gas purging increases the surface area and pore volume, although steam activation is not much suitable to improve the BC surface functionality as compared to chemical and impregnation activation. Sulphuric and oxalic acid-modified biochar was found to be most suitable for the soil amendment. Alkaline activation enhances the surface area and oxygen-containing functional group in activated biochar. Metal oxide-modified biochar had better surface functionalities than did physical- and chemical-activated biochar and better sorption of organic and inorganic contaminants from potable water and waste water. In summary, activated biochar has a wide environmental prospect in remediation.

关键词： Muskmelon   Pectin   Bonding state   Sugar composition   Viscosity  

摘要： Pectin is one of the crucial endogenous components in cloudy juice and easily affects cloud stability due to its stabilizing property. To obtain improved cloud stability, the physicochemical and structural characteristics of pectin fractions from muskmelon and their correlation with juice cloud stability were investigated. In this study, a water-soluble pectin fraction, a trans-cyclohexane-1,2-diaminetetraacetic acid (CDTA)-soluble pectin fraction, and a sodium carbonate-soluble pectin fraction were sequentially extracted from the whole muskmelon fruits. All pectin fractions were classified as low-methoxy pectin and contained 3.06-8.26% protein. Measurements of the monosaccharide compositions and microstructure showed that CDTA-soluble pectin and water-soluble pectin consisted of aggregates of linear homogalacturonan, whereas sodium carbonate-soluble pectin was more highly branched. Analysis of Fourier transform infrared and nuclear magnetic resonance spectroscopy revealed observable differences between the chemical structures of the three pectin fractions. Thermogravimetric analysis indicated sodium carbonate-soluble pectin had the highest thermal stability than other pectin. Of all pectin fractions, CDTA-soluble pectin had the highest molecular weight, which resulted in the highest apparent vis-cosity. Moreover, the principal component analysis showed that CDTA-soluble pectin played an important role in cloud stability. This study will provide valuable information for the melon juice industry with regard to the utilization of pectin to improve cloud stability.