高职“聚合物合成技术”项目化课改——“情感注入、四动一定、熟能生巧”之探讨

"聚合物合成技术"通过以合成典型高分子产品为项目载体,实施理实一体项目化教学改革。通过改革,凝练两大特色:项目设计有理念,"吃出方法、吃出味道、品出文化";项目实施有特色,"情感注入、四动一定、熟能生巧"。在轻松的师生关系前提下,在充满赏识的教学氛围中,学生熟"四动",巧"一定",真正实现"做中学、学中做、学做一体"课改实效,使课改脚踏实地、落地有声。     

混合教学模式在有机化学课程教学中的应用

针对目前高职院校有机化学教学中面临的难题,本文以"羧酸"教学为例,探讨了混合教学模式在有机化学教学中的应用,采用在线学习和课堂教学相结合的方式实施翻转课堂教学,使课堂教学模式由"以教为主"转变为"以学为主",同时根据高职院校学生的特点,采用问题式学习任务单的方式和组长负责制的分组学习模式。实践证明,教学效果良好。     

有机化学实验“四位一体”教学模式的实践与探讨

以苯甲酸正丁酯的合成为例,介绍了有机化学实验"学、教、做、评"四位一体的教学模式。以导学、助学、促学、先学后教等方式促进学生自主学习的积极性;采用以问题为中心的教学方法,确立了以教师为主导、学生为主体的师生关系,充分发挥了学生的主观能动性;以开放性实验代替传统实验,充分培养了学生的实验技能和科学素养;对实验成绩进行综合立体评价,体现了评价的客观性和真实性。实践表明"四位一体"的教学模式不仅能够充分调动学生的主观能动性,培养学生的实验技能和兴趣,而且能有效地提高实验教学质量。     

促进科学观念与科学实践协同发展的学生必做实验的教材编写

国内外科学教育界普遍认为,科学观念与科学实践的协同发展是培养学生科学素养的重要途径。教材对于学生必做实验的编排和处理,对于教师的教学设计及实施具有重要的影响。简要介绍了科学观念与科学实践协同发展的内涵,并针对北京师范大学“新世纪”山东科学技术出版社高中化学必修教材中的学生必做实验编写的整体情况和具体策略进行了深入分析,阐释了该教材对于学生必做实验的编写是如何体现科学观念与科学实践的协同发展、彰显这些实验的核心素养发展功能的,并提出了新教材学生必做实验的教学实施建议。     

医学化学课程中开设专题研讨课的实践

以2011级本科医学心理学专业学生为研究对象,尝试在医学化学课程部分章节的教学实施中增加"阿尔茨海默病与生物元素"的专题研讨。通过比较增加研讨课前后的教学效果,发现采用该模式进行教学后,学生的学习兴趣、学习主动性有了较大提高,同时提升了发现问题、分析问题和解决问题的能力。     

小组作业及Origin软件在高分子化学教学中的应用

将Origin软件用于高分子化学教学,选择合适的习题设计成小组作业,并通过翻转课堂进行交流、总结,让学生在做中学、教中学、学中做、学中思,取得了良好的教学效果。找到了将工程教育专业认证所要求的,学生使用现代工具的意识与能力、合作意识与能力、交流与表达能力的培养,渗透、融入到高分子化学教学中的结合点与切入点,找到了在高分子化学教学中培养学生上述意识与能力的具体方法与实现形式,使学生在完成这些小组作业的过程中,不仅学会并练习用Origin软件解决高分子化学相关问题,同时相关意识与能力也得到培养。同时,也使"以学为中心"、"以学生为中心"的理念在教学设计与教学实践中得到有效贯彻。     

初中"科学"课堂中学生学习行为的特征及其影响因素

从综合科学课程改革实验区的"科学"课堂入手,运用质化的研究方法对学生的学习状态及学习行为进行观察分析和总结,进而阐述"科学"课中学生学习行为的主要特征,以及影响学生学习行为的主要因素.希望通过对"科学"课堂的观察与思考给目前的理科教学提供一定的启示,使学生养成良好的学习行为,更好的促进学生科学素养全面的、主动的发展.     

谈"物质的分类"在新教材中的地位和作用

新教材中"物质的分类"这一节内容是连接初、高中化学的纽带和桥梁,具有非常重要的承前启后的作用,我们应该把衔接教学的思想渗透到整个教学过程中去,使知识间的跨度小一些,让学生接受容易一些;物质的分类也是学习和研究化学物质及其变化的一种常用科学方法,我们要让学生学知识的同时学到方法——"鱼"、"渔"兼得。     

提高探究学习活动的实效性

探究学习活动实质上是让学生在做中学,不是辅助教师"灌输知识"的手段.新课程实施要努力提高探究学习活动的自主性、探究性和实效性.教师要尊重学生学习的主体地位,关注学生在学习上可能出现的问题,注意挖掘学习课题中蕴涵的科学方法、思维训练等教育因素,注意创设能引发学生发现问题、找到探究实验设计思路的真实情景,注意探究学习活动和其他教学环节的整合.     

“厚基础、强能力、重探究”教学模式的探索与实践

传统的化学实验教学,特别是基础实验阶段,大多采用"听老师讲、照书本做"的模式,忽略了对学生自主学习能力和探究能力的培养。为提高学生的积极性,培养学生的创新能力,提升课程的教学质量,在基础化学实验中探索并实践了"厚基础、强能力、重探究"的新型三阶段教学模式,即巩固基本操作、强化综合技能、突出自主探究。经过近五年的实施,取得了较好的教学效果。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.