基于Rasch模型的高中化学学科核心素养测评研究——以“变化观念与平衡思想”为例

以《普通高中化学课程标准(2017年版)》对“变化观念与平衡思想”素养的内涵描述和水平划分为例,开发高中生“变化观念与平衡思想”素养测试题,运用Rasch测量模型对工具的质量进行检验、优化并加以运用。结合测试数据调查了学生“变化观念与平衡思想”素养水平现状,分析了研究被试能力值的学校差异和班级差异,并对该素养培养提出建议。     

剖析师生对绿色化学的认知偏差

在绿色化学思想逐渐普及的同时,发现许多学生和教师对“绿色化学“和“绿色化学实验”的认知存在偏差。学生错误地认为“绿色化学”就是任何时候都禁止排放任何废物的化学;教师错误地认为：实施绿色化学实验教学时,不能向教室或实验室泄漏一丁点废气,致使学生的嗅觉等感官体验被剥夺,造成他们对事物的感知不完整。     

“绿色化学”的项目式教学*——环氧乙烷制备工艺中的绿色化学

以“环氧乙烷制备工艺中的绿色化学”为项目式学习主题,以绿色化学概念学习、化学工艺中绿色化学的设计评价等为项目学习活动,探究绿色化学理念的教学设计。培养学生绿色化学意识,提升科学态度和社会责任的化学学科核心素养。     

试论化学核心素养的结构

化学核心素养包含了“化学”的素养、“核心”的素养、“人”的素养三重意蕴。基于对化学核心素养的概念分析和层次分析,提出其四维度结构模型。在4个维度中,“化学基本观念”是基础维度,“化学过程”和“化学在生活中的应用”是2个活化维度,“对化学的态度”是动力维度。化学核心素养为学术性化学素养和生活性化学素养的发展同时奠定了基础。把握3种化学素养在结构和具体维度上的差异有助于理解化学核心素养的内涵,也有助于把握中学化学课程中不同模块的教学定位。     

高中生对化学课堂环境感知的调查研究

采用“中学化学课堂环境问卷”作为研究工具,对深圳市、长春市、佳木斯市等3个地区的4所高中861名学生的化学课堂环境进行调查,并进行差异分析。研究结果表明,高中生对化学课堂环境的总体感知较好,7个维度中“学生凝聚力”“平等”“任务取向”“合作”等4个维度的平均分大于3.4,“教师支持”和“参与”维度的平均分在3.0~3.4,只有“探究”维度的平均分小于3.0。城市高中生对课堂环境的感知明显好于乡镇高中生,学生心目中所期待的化学课堂比实际的化学课堂更积极。     

核心素养视角下人教版新旧教材中“硫及其化合物”的对比分析*

选取人教版新旧必修化学教材中的“硫及其化合物”单元作为研究对象,基于新课标中化学学科核心素养的培养视角,明确了新课标对“硫及其化合物”的素养定位后,对新旧教材中该单元的引言、正文、栏目和插图进行对比分析。对比分析结果显示,新教材“硫及其化合物”的内容侧重“证据推理与模型认知”素养的培养,其次是“宏观辨识与微观探析”“科学态度与社会责任”素养,而在素养水平上则侧重水平1和2维度的培养,符合新课标对该主题单元的学业要求和素养定位。     

从“精灵”到催化“多面手”的钴元素

钴因德语中“Kobold”一词而得名,从最早发现时的“精灵”到现在已成为催化“多面手”。回顾了钴元素的发现与得名过程以及钴元素在化学学科发展过程中的重要历史意义,介绍了钴元素作为催化剂的活性中心在清洁能源和绿色合成方面的相关应用。     

高中生化学人文素养现状的调查与思考

基于已有研究和实践调查,提出化学人文素养的三维模型,即“知”“信”“行”。“知”包括人文知识与价值传承,“信”包括创新意识与探究精神,“行”包括健康生活与社会责任。以此模型设计研究工具,对北京市普通高中的272名学生的问卷调查及68名学生的访谈显示,学生自认为人文素养略高于“一般”水平,只有33.3%的学生获得了一定的人文知识和价值传承(知),以及具有健康生活和社会责任意识(行),仅20.0%的学生获得了一定的创新意识和探究精神(信)。基于此,从化学史、化学实验、化学与生活3个切入点提出人文素养提升的建议。     

促进学生“科学探究与创新意识”素养的发展*——以“氢氧化亚铁的制备”为例

以“氢氧化亚铁的制备”教学设计为例,通过开展专题课,引导学生深入探究氢氧化亚铁制备实验的设计与改进,重点关注学生“科学探究与创新意识”素养水平的发展,并基于具体的测评数据进行反馈评价。     

化学师范生模型认知能力的测查研究

“模型认知”是化学核心素养的重要组成部分，本研究确立了化学模型认知能力的构成要素及其相关的表现指标，并设计调查问卷探查化学师范生“模型认知”能力现状。调查结果显示：化学师范生“模型认知”能力整体水平不高，随年级升高，无性别差异。     

UV‐Triggered Surface‐Initiated Polymerization from Colorless Green Tea Polyphenol‐Coated Surfaces

A facile and versatile approach to constructing colorless surface coatings based on green tea polyphenols is reported, which can further act as a photoinitiating layer to initiate radical polymerization. These colorless green tea polyphenol coatings are capable of successfully photografting polymer brushes, and the resulting polymer brush patterns show spatial shape adjustability by masked UV irradiation. Both surface modifications and photografted polymer brushes do not alter the original color of the substrates. This method could be promising for the development of surface modifications.

     

Microcalorimetric investigation of the growth of the engineering <Emphasis Type="Italic">BACILLUS</Emphasis><Emphasis Type="Italic">THURINGIENSIS</Emphasis> with different plasmid numbers and various promoters

A microcalorimetric technique based on the bacterial heat output was applied to evaluate the influence of plasmid copy number and various promoters on the green fluorescent protein expression in Bacillus thuringiensis. The thermogenic curves of the aerobic metabolism of B. thuringiensis strains were determined by using an LKB-2277 bioactivity monitor at 28°C. The analysis of the thermogenic curves indicated for the first time that the more plasmid copy number per cell the more protein synthetization. Promoter BtI-BtII had a stronger impact on the gene expression than promoter 3A investigated by the method of microcalorimetry.     

Green and rapid preparation of thermally stable and highly organosoluble polyamides containing L‐phenylalanine‐9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido moieties

A chiral diacid monomer containing L ‐phenylalanine‐9,10‐dihydro‐9,10‐ethanoanthracene‐11,12‐dicarboximido unit was successfully synthesized in four steps and used in the preparation of a series of novel optically active polyamides by direct polycondensation with diverse aromatic diamines using 1,3‐dipropylimidazolium bromide under microwave dielectric heating. Ionic liquids (ILs) efficiently absorb microwave energy and thus are employed as solvent. By controlling the concentration of 1,3‐dipropylimidazolium bromide, reaction time and power level, high yield and moderate inherent viscosity polymers could be achieved in a very short period of time. All the resulting polymers exhibited excellent solubility in various organic solvents. The polyamides were found to have inherent viscosities in the range of 0.54–0.85 dL g^?1. These polyamides had glass‐transition temperatures (T_g) above 180°C, and a 10% weight‐loss temperatures in excess of 340°C with char yield at 800°C in nitrogen higher than 40%. A comparative study on effects exerted by microwave technique with conventional method is also presented. Copyright © 2009 John Wiley & Sons, Ltd.     

High‐Performing Red‐Light‐Emitting Pyrotechnic Illuminants through the Use of Perchlorate‐Free Materials

The development of perchlorate‐free M662 40 mm illuminating pyrotechnic compositions is described. On the bases of cost, performance, and sensitivity, potassium periodate was determined to be most effective potassium perchlorate replacement in the compositions tested. The optimal periodate‐based composition exceeded the performance of the perchlorate‐containing control, exhibited low sensitivity values to impact, friction, and electrostatic discharge, and had high thermal onset temperatures.     

Preparation of choline chloride–urea deep eutectic solvent‐modified magnetic nanoparticles for synthesis of various 2‐amino‐4H‐pyran derivatives in water solution

A novel hybrid magnetic nanocatalyst was synthesized by covalent coating of Fe₃O₄ magnetic nanoparticles with choline chloride–urea deep eutectic solvent using 3‐iodopropyltrimethoxysilane as a linker. The structure of this new catalyst was fully characterized via elemental analysis, transmission and scanning electron microscopies, X‐ray diffraction and Fourier transform infrared spectroscopy. It was employed in the synthesis of various 2‐amino‐4H ‐pyran derivatives in water solution via an easy and green procedure. The desired products were obtained in high yields via a three‐component reaction between aromatic aldehyde, enolizable carbonyl and malononitrile at room temperature. The employed nanocatalyst was easily recovered using a magnetic field and reused four times (in subsequent runs) with less than 8% decrease in its catalytic activity.     

Solvent‐free reactions of alcohols with β‐dicarbonyl compounds catalyzed by iron(III) chloride

The direct substitution of alcohols and β‐dicarbonyl compounds was catalyzed with FeCl₃ under solvent‐free conditions. The catalyst loading could be decreased to 0.01 mol% at high activities. It was shown that the reaction proceeded in two steps via the etherification of the alcohols. This method provided an easy and practical procedure for C? C bond formation.Copyright © 2007 John Wiley & Sons, Ltd.     

Metal‐ and Reagent‐Free Dehydrogenative Formal Benzyl–Aryl Cross‐Coupling by Anodic Activation in 1,1,1,3,3,3‐Hexafluoropropan‐2‐ol

A selective dehydrogenative electrochemical functionalization of benzylic positions that employs 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP) has been developed. The electrogenerated products are versatile intermediates for subsequent functionalizations as they act as masked benzylic cations that can be easily activated. Herein, we report a sustainable, scalable, and reagent‐ and metal‐free dehydrogenative formal benzyl–aryl cross‐coupling. Liberation of the benzylic cation was accomplished through the use of acid. Valuable diarylmethanes are accessible in the presence of aromatic nucleophiles. The direct application of electricity enables a safe and environmentally benign chemical transformation as oxidizers are replaced by electrons. A broad variety of different substrates and nucleophiles can be employed.     

Star‐like polyfluorenes based on 2,4,6,8, 10,12‐hexabenzyl‐2,4,6,8,10,12‐hexaazaisowurtzitane caged‐core: toward non‐aggregating,blue‐light‐emitting polymers

Multi‐functionality compound 2,4,6,8,10,12‐hexa(p‐bromo)‐benzyl‐2,4,6,8,10,12‐hexaazaiso‐wurtzitane (Br‐HBIW) was synthesized and used for the core of star‐like polymers. Star‐like polyfluorene based on 2,4,6,8,10,12‐hexabenzyl‐2,4,6,8,10,12‐hexaazaisowurtzitane (HBIW) caged‐core was synthesized by Suzuki coupling method. The comparative studies between the star‐like polyfluorene and the linear polyfluorene based on UV–Vis and photoluminescence (PL) spectra revealed that the bulky HBIW cage could reduce the chain aggregation and π–π interaction, so brought about improved PL quantum efficiency and annealing PL stability. Such results could be owed to the successful suppression of excimers formation, which originated from the incorporation of the HBIW cage and star‐like architecture. Copyright © 2009 John Wiley & Sons, Ltd.