基于高中生概念认知水平的定量化能力测评研究

采用定量、定性相结合的研究方法探究基于高中生概念认知水平的定量化能力水平特征。研究结果表明,建构的定量化能力框架符合学生认知水平发展,编制的测量工具经Rasch模型检验具有良好的信度和效度;高中生定量化能力呈“U”型分布;数学、化学学科学业水平与学生定量化能力呈显著正相关;中、低能力水平学生在选择题、建构反应题上表现有显著差异。     

高中生“绿色应用”素养的测评研究

基于绿色化学对社会可持续发展的重要性,提出科学教育中“绿色应用”素养的理论框架,结合高中生化学学习特征开发测评工具,实施测量,分析处理测试数据,探查了高中生“绿色应用”素养的行为水平。研究发现,高中生“绿色应用”素养水平与其学科能力水平具有较好的一致性,不存在性别差异。测评结果为绿色化学实践提供借鉴和启发,以促进学生“绿色应用”素养的提升。     

基于Rasch模型的“化学实验认知能力”测验工具编制及测评研究

"实验认知"贯穿于化学实验活动的全过程,是化学实验能力的核心成分。基于Rasch模型原理及Wilson测量建构"4基石"方法,对"化学实验认知能力"进行了水平构建、测验工具的开发及优化、能力测验及数据分析。研究显示,测验所获数据符合Rasch模型预期,测验工具具有良好的信度、效度。依据测验数据,探讨了不同年级学生"化学实验认知能力"的水平分布,分析了"化学实验认知能力"的年级差异和学校差异,提出了化学实验教学改革的方向。     

利用手持技术探究原电池“电极反转”双模型的反应机理

基于手持技术表征原电池基准态与极端态工作原理的差异性,继而探究铁和铝分别与铜在浓硝酸中构成的2种极端态原电池在发生电极反转时硝酸浓度的临界值。通过双模型对比实验,帮助学生更加直观、准确、深入地建构原电池模型,同时丰富学生对元素周期律、金属活动性以及氧化还原反应等关联性知识的认知与理解。     

整合多重表征 促进概念深度理解——以“原电池”为例

有效整合多重表征,是促进学生科学概念深度理解的一种有效策略。本研究整合了科学教育领域中的3个多重表征框架的内容,对高中必修模块的“原电池”进行了教学设计。首先引导学生依次学习原电池的宏观装置、微观原理和电极符号,初步建构原电池概念,之后基于氢氧燃料电池关联表征,让学生建构原电池的装置原理二维模型图,理解原电池概念,最后依托生活中的纽扣电池应用二维模型图实现表征转换,解决实际问题,实现对原电池概念的深度理解。     

利用手持技术数字化实验促进学生原电池概念认知*——ZnCu稀硫酸原电池与Zn和稀硫酸反应的比较

以ZnCu稀硫酸原电池与Zn和稀硫酸反应的比较实验为例,探讨根据TQVC概念认知模型,设计促进学生原电池概念认知的手持技术数字化实验。具体过程是:将原电池概念关键内涵转化为可测量的温度和电流概念的关联属性,利用温度传感器和电流传感器测量实验的热能和电能的变化,通过实验数据、曲线及其四重表征分析得到实验结论,并判断实验设计的有效性。对实验设计的关键和实验证据的使用进行了讨论。     

基于证据推理与模型认知素养及跨学科概念的“原电池”教学

以“原电池”教学为例,通过设置紧密联系的任务,结合手持技术,探究“如何获得稳定工作的电池”和“如何获得高效的电池”的原理。充分运用物理、化学已有的认知模型,进行跨学科概念的教学,培养学生从宏观和微观水平上收集证据、分析证据的能力,发展“证据推理与模型认知”的学科核心素养。     

论证式教学对高中生化学概念学习的影响——以原电池为例

以“原电池”及其相关概念为例，探讨论证式教学对高中生化学概念学习的影响。研究对象为131名高二年级学生，其中对照组64人，实验组67人。教学前后，分别对学生的“原电池”概念学习情况进行了测试。实验结果显示实验组学生成绩显著优于对照组学生，表明论证式教学能显著提高学生对“原电池”概念的理解，大多数学生对论证式教学持积极态度。     

中学生实验图式的建构——以原电池形成条件实验为例

原电池形成条件的系列探究实验在课堂教学设计和实验改进方面的研究都比较成熟,但对探究实验所引发的学习心理历程的审视与解读却相对薄弱。基于认知科学视角,剖析了关于原电池形成条件的实验图式的构成要素,描述了其认知建构历程,并提出教学建议。     

电化学认识模型及其在高三原电池复习教学中的应用

综述了关于高中原电池教与学的已有研究,分析了电化学知识要求和学生电化学认识特点,从电化学的本体维度、认识维度和问题维度,构建并提出了高中电化学认识模型,并在高三原电池复习教学中进行了应用,针对分析型任务和设计型任务进行对比性教学实验。通过对学生电化学认识发展的前后测及其对比统计分析,并结合学生访谈对教学效果进行了检验,在此基础之上进一步分析和概括了基于电化学认识模型建构的原电池复习教学有效策略。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。