手持技术数字化实验慕课使用意愿的影响因素研究*——基于TAM3模型的PLS-SEM分析

在第三代技术接受模型(TAM3)的理论基础上,以华南师范大学化学学院2017级职前化学师范生为研究对象,构建手持技术数字化实验慕课的使用意愿模型。利用SmartPLS3.0软件,以偏最小二乘结构方程实证该模型的科学性。结果发现:(1)主观规范、产出品质和个体创新对感知有用性存在显著的正相关;(2)自我效能和感知愉悦性对感知易用性存在显著的正相关,而个体创新对感知易用性的影响并不显著;(3)感知易用性对感知有用性存在显著的正相关,2者对行为意向有显著的直接影响,而主观规范对行为意向的影响并不显著。基于以上结果,对手持技术数字化实验慕课的建设提出对策建议。     

化学职前教师手持技术TPACK调查研究

设计了《化学职前教师手持技术TPACK量表式问卷》,对223名化学职前教师进行问卷调查,采取探索性因子分析与验证性因子分析检验问卷的信度、效度以及七因子模型的合理性,同时通过结构方程模型构建并讨论化学职前教师手持技术TPACK的发展路径。研究结果表明：(1)问卷具有良好的信效度;(2)TPACK七因子模型具有一定的合理性;(3)化学职前教师手持技术TPACK的发展路径中除CK对PCK无直接影响外,均支持TPACK的变革观点。文末据此对手持技术TPACK基础研究与化学教师发展两方面提出相应的建议。     

基于TPACK研究手持技术在中学化学课堂教学的应用现状

为了解中学化学教师对手持技术的应用水平和影响因素。以整合技术的学科教学知识（TPACK）理论为依据,创新性地将境脉（Context）因素引入TPACK调查中进行问卷设计,并对来自于全国16个省直辖市的187位教师进行了网络问卷调查,同时采用SPSS软件对问卷进行信效度评价,采用SPSS AMOS对问卷进行探索性因子分析,并对调查结果进行分析。研究结果显示中学化学教师手持技术TPACK量表结构模型较好,能够用于评价中学化学教师的手持技术应用水平;中学化学教师手持技术应用情况良好,但是与性别、教龄、学校类别有显著关系。针对研究结果,提出提高中学化学教师手持技术应用水平的发展建议,以期提高中学化学教师手持技术在中学化学教学的应用水平。     

化学师范生的TPACK与化学认识信念及其关系研究

测查246名化学师范生的TPACK与化学认识信念的结构与水平,并使用结构方程模型进一步探查2者的关系。结果表明,师范生的化学TPACK尚属中等水平,其化学认识信念为建构主义知识观取向,化学认识信念的5个维度对TPACK均有显著的预测作用。     

我国化学教育类硕士的TPACK现状调查与分析

为在宏观上了解化学教育类硕士是否具有进行有效技术整合所必需的知识,基于TPACK提供的知识框架,对我国230名化学教育类硕士的TPACK水平及影响因素进行调查。结果表明,化学教育类硕士TPACK呈中等偏上水平;学术型硕士的TPACK水平高于专业型硕士;学习经历和实践经历对TPACK各要素有不同程度的影响;学习能力对TPACK的发展无显著影响;TPK、TCK和CK是影响TPACK发展的主要因素。在此基础上,提出了提升TPACK水平的相关策略。     

化学师范生TPACK影响因素的质性研究

通过开放性问卷、半结构化访谈等数据收集工具,采取质性研究方法对数据进行自下而上的分析,探查化学师范生TPACK的影响因素。结果表明,影响因素可分为客观因素与主观因素,其中客观因素主要包含宏观、中观及微观层面的外在因素,主观因素主要为化学师范生的知识、信念与能力。据此对我国化学师范生培养以及后续研究提供参考。     

化学教师的TPACK结构及建构策略

随着教师职业的不断发展,教师进行有效教学的核心就是发展他们的TPACK,化学教师的TPACK主要包括:扎实科学的化学学科知识、信息技术与化学教学整合目的的统领性观念、信息技术与化学教学整合的课程资源和课程组织知识、关于信息技术与化学教学整合的学生理解和学生误解知识、信息技术与化学教学整合的教学策略和教学表征知识。化学教师TPACK建构的基本策略有:形成TPACK的教学意识、观摩培训、亲自参与教学、提升整合转化能力、多渠道多种方式丰富TPACK资源。     

TPACK视野下“整合技术的化学教学知识”的案例研究——以“氨”为例

以国外对TPACK进行的相关研究及成果为基础,选择中学化学学科作为切入点,从理论研究的视角提出了"整合技术的化学教学知识(TPCHK)"结构模型,并分析其内涵。同时,以中学一线教学实践为基础,从实践微观的视角,通过对"氨"一课教学实践的案例分析,详细讨论了教师应具备的TPCHK结构,为TPACK在我国本土化学学科中的教学实践研究提供参考。     

TPACK知识框架下中学化学体验式教学的研究

以国外整合技术的学科教学法(TPACK)知识框架的相关研究及成果为基础, 选择中学化学学科作为切入点, 由教师进行信息技术与课程整合所需知识为载体, 在对TPACK支持下的体验式学习活动构建的基础上, 以“原电池”一课的实践为例, 从主题选择、软件设计、教学实施、教学反思等方面开展了较为系统的、微观的、实证的研究, 以期为我国TPACK本土实践研究提供一定的借鉴作用。     

化学师范生对化学本质及其教学的认识研究

使用问卷调查法与访谈法,以广东某高校的化学师范生为样本,测查了30名化学师范生对化学本质的认识状况、教学意愿及教学策略。结果表明,（1）师范生对化学本质（包括化学知识的性质、来源、论证、评价等维度）的认识主要体现了辩证唯物主义取向;（2）师范生仅在对个别化学本质维度的认识上涉及到化学的学科专属性;（3）师范生有进行化学本质教学的意愿并能阐述原因,但缺乏进行化学本质教学的策略。据此对我国化学师范生教育及其研究提出相关建议。     

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.