运用科学阅读策略提高中学生的化学学习能力

科学阅读是科学学习的重要组成部分,将科学阅读策略应用于化学学习中,有利于学生对化学概念和化学知识的理解,有利于学生将新知识、新概念整合到自己的认知结构中,从而达到有意义的学习。     

发展学生化学学科核心素养离不开化学实验

化学实验是化学教学的重要组成部分,不仅具有教育教学功能,而且具有发展学生化学学科核心素养的功能。从认识层面、实践层面和价值追求层面来看,化学实验在发展学生科学本质观、科学实践观和科学价值观方面均发挥着不可替代的功能。教师可以利用化学实验史实呈现真实的科学发现过程,发展学生的科学本质观;可以通过引导学生对化学实验现象的观察和基于实验事实证据的推理发展学生“宏观辨识与微观探析”“证据推理和模型认知”素养;可以通过开展化学实验探究,引导学生拓宽认识视角和认识思路,发展学生“科学探究与创新意识”素养;可以通过化学实验评价发展学生的“科学态度和社会责任”素养。     

论化学史教育的职业教育功能

在化学教学中适当地穿插化学史事例进行的教学,一般称之为化学史教育。学习和研究化学史的重要意义已为化学家和化学史家所重视,并且也为教育领导部门所重视。在1988年,我国著名化学家和化学教育家戴安邦教授就说过：“全面的化学教育既要传授化学知识与技术,更应训练科学方法和思维,还应培养科学精神和科学品德。”著名化学家傅鹰也说过：“化学给人以知识,化学史给人以智慧”。因此,化学史教育也是全面的化学教育的一个组成部分。通过化学史教育,不仅可以培养学生的职业道德,还可以培养学生的科学实践意识,发展学生的创造力。     

运用化学史料提高学生的科学探究能力

化学发展的历史就是科学探究的历史,化学史料十分丰富,在化学教育中充分应用化学史料进行教学,可以提高学生提出问题的能力、猜想和假设的能力、形成结论的能力以及评价与反思的能力等基本要素,因而能够提高学生的科学探究能力。     

化学问题解决中的科学方法教育

科学方法教育不仅是中学理科教学的重要内容,更是培养学生实践能力和创新精神的重要途径。化学教学活动的要旨之一是让学生获得科学方法的训练,从而培养化学学科意识、思想及精神。本文从有机化学问题解决案例教学中如何注重分类与比较、分析与综合、归纳与演绎这3类常见的方法入手,落到实处,试图为科学方法教育提供便于实施的操作性建议。     

初三化学教学要重视对学生进行学习目的和辩证唯物主义观点的教育

初三化学是中学生学习化学的开端.??教师要引导学生爱好化学,学好化学,可以通过多种途径.现就对学生进行学习目的教育和辩证唯物主义观点教育,谈点看法. 一、明确教学目的,结合实际对学生进行学习目的教育. 为了使学生学习化学有个良好的开端,必须让他们明确学习化学的目的和重要性,这一点非常重要. 在化学的第一堂课——绪言上,就要使学生清楚地知道:世界是物质的,化学研究的对象就是物质.所以,化学研究的范围是非常广泛的,化学与各门科学、工农业生产、国防建设和     

为学生构建神奇的化学史与化学美的世界

化学教学,既是一门科学,又是一门艺术。科学精神体现在不尽的教学探索中,而对教学艺术的追求,也是永远没有穷尽的。化学史与化学美中具有科学、人文和审美的重要内容。作为化学教师,笔者深感为学生构建神奇的化学世界,应该是我们教师最重要的工作。多年来,笔者努力开展化学史与化学美教育,探索为学生构建神奇的化学史与化学美的世界。1为学生构建神奇的化学史的世界1.1统计、挖掘教材中的化学史内容伟大的法国物理学家、教育家、科学史家、诺贝尔物理学奖获得者郎之万曾经尖锐地批判在科学教育中,只向学生灌输科学知识的教条主义、形式主义…     

转变中学化学前科学概念的课堂观察系统

化学前科学概念、教师教学方式与提问类型、学生课堂参与度和学习目标达成度等4个维度构成的课堂观察系统,可以观察、统计师生课堂行为,评估来自教学实践的前科学概念转化策略的有效性。     

基于雨课堂和BOPPPS改进模型的教学设计——以大学化学课程为例

在高等学校专业课程教学中融入思政教育教学的理念,是以"立德树人"为教育根本任务的基本要求。结合结构化学课程特点和教学内容,以"培养学生的哲学观和科学观、培养学生民族自豪感和自信心"的目标为切入点,提出结构化学教学中思政元素的融入策略,发挥结构化学课程的"育德功能",实现知识传授和价值引领的有机统一。     

快乐化学伴你成长——读美国高中化学教科书有感

美国高中科学教科书《化学:概念与应用》让阅读变成了一种享受,学习科学也变得趣味盎然.我们的化学教学也要多一些体验,引导学生像科学家那样思考、探索与发现.     

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。