教材在教育教学工作中占有非常重要的地位.在系统分析2019人教版高中化学必修教材各栏目的过程中,发现该教材蕴含着丰富的劳动教育资源,经过进一步挖掘和整理,可归纳为认知、实践和价值三个层面;基于ADDIE教学设计模型提出化学教学中劳动教育资源的应用思路,并以"化学能转化为电能——原电池装置"为例进行教学设计.劳动教育与化学教育的深度融合,不仅可以增进学生对化学科学的理解和兴趣,还可以帮助学生树立正确的劳动观,落实"五育"并举的教育方针.
文章设计合成了含有偶氮苯和羧酸钠基团的pH响应性阴离子型两亲分子(C6-Azo-COONa),通过1H NMR和元素分析的方法对两亲分子的结构进行了表征.并利用动态光散射(DLS)、冷冻刻蚀电子显微镜(FF-TEM)、光学显微镜(OM)、X-射线衍射(XRD)和扫描电子显微镜(SEM)等手段研究了其在不同pH值的水溶液中所形成有序聚集体的形貌和结构.研究发现,C6-Azo-COONa在水溶液中可自组装形成球形胶束,当把溶液pH值调至酸性后,胶束转变为多级层状微米带结构,当把此酸性溶液再调为碱性后,胶束又可以重新形成.此外,在微米带形成的过程中,偶氮苯基团起到了必不可少的作用.
基于学生在学习彼此割裂的化学平衡移动三判据时存在明显的学困现象,针对吉布斯自由能变化ΔG与化学平衡常数K与浓度商Q的定量比较在当前课堂教学中等价性证明的欠缺,对吉布斯自由能变化与化学平衡常数的关系进行了数学推导.该推导解决了吉布斯自由能变化作为化学平衡移动的判据在课堂教学中过于突兀呈现的问题,为学生追求化学中蕴含的数学美提供了示范.
Multiple-responsive supramolecular vesicles have been successfully fabricated by the complexation between β-cyclodextrin (β-CD) and a pH/photo dual-responsive amphiphile 4-(4-(hexyloxy)phenylazo)benzoate sodium (HPB) with azobenzene and carboxylate groups. When mixing β-CD with HPB to reach a host/guest molar ratio of 1 : 1, the azobenzene group of HPB could be spontaneously included by β-CD molecules. Then, the formed inclusion complexes (HPB@β-CD) could self-assemble into vesicles, which was driven by the hydrophobic interaction of the alkyl chain of HPB and the hydrogen bonds between neighboring β-CDs. The reversible assembly/disassembly of the vesicles could be simply regulated under UV or visible light irradiation. The reversible phase transformation between vesicles and microbelts could also be realized by adjusting the pH values of the sample. Adding both competitive guest molecules (1-adamantane carboxylic acid sodium (ADA)) and α-amylase would result in the phase transformation from vesicles to micelles. Moreover, the vesicles would be destroyed when β-CD was continuously added until the ratio of host/guest reached 2 : 1. Such an interesting quintuple-responsive vesicle system reported here not only has potential applications in various fields such as controlled release or drug delivery, but also provides a reference for the design and construction of multiple responsive systems.
