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1.
王星乔  包朝龙 《化学教育》2020,41(21):35-41
针对当前高三化学实验常态复习难以适应“素养为本”的实验试题考查要求的现状,提出了以深度学习指引高三化学实验有效复习的设计思路:精选学习主题、设计学习任务、进行实时评价,并以“七水合硫酸锌的制备、葡萄糖酸锌的制备、葡萄糖酸锌的纯度测定、构建认知模型”为主线,设计了“葡萄糖酸锌的制备及纯度测定”一课,为高三化学实验的深度复习提供了可资借鉴的设计思路和教学案例。  相似文献   

2.
杨发丽 《化学教育》2018,39(5):49-53
以"煤的综合利用"高三复习教学为例,基于化学核心素养确立教学目标,将"化工厂如何解决煤燃烧产生的SO2"科学家如何选择煤气化的反应条件"这2个问题的讨论作为重点,并详述以上教学环节。对教学的实施和目标的落实进行了总结反思:创设真实情境,有效发展化学学科核心素养;创新教学设计,激发学生学习兴趣;用好问题串,促进知识、思路结构化;精心设计,促进素养显性化。  相似文献   

3.
钟国华 《化学教育》2022,43(17):87-93
以2021年高考广东卷为例进行试题情境与类型研究,发现试题情境化的特点。分析情境教学的研究现状,提出基于真实情境的高三化学微专题教学设计模型,概述其要素构成、一般流程。基于课例探讨从回归教材知识、深度挖掘试题、制造认知冲突等方面创设教学情境,结合三元整合教学策略提出设计课堂问题的角度,以期提升课堂教学的有效性,为高三化学微专题复习提出教学建议。  相似文献   

4.
袁君亚 《化学教育》2022,43(7):21-25
以高三复习课“平衡原理的应用”为例,通过真实情境的剖析让学生感知模型,引导学生分析归纳提炼模型,并进行针对练习运用模型,变式训练体会模型,让学生在实践中以模型思维为突破,深入领悟建构模型的实质,有序解决复杂化学问题,提升科学思维能力,发展化学学科核心素养。  相似文献   

5.
高三化学复习的应遵循“高效性、有效性、针对性”的原则.本文重点结合镇江市的复习教学实践和所见所闻所思探讨复习中常见的3种偏差现象及防偏策略,以便更好地提高复习效率,进一步提升学生的化学素养.  相似文献   

6.
林秀銮  张贤金 《化学教育》2022,43(23):67-72
针对高三定量实验的复习特点,以“摩尔盐纯度的测定”为例进行基于“模型认知”核心素养培养的教学实践。对教学背景、设计思路、教学过程等方面进行研究分析,并从精心选素材,引发模型认知;高质量设问,建构模型认知;点、线、面结合,丰富模型认知等3个角度对促进学生“模型认知”素养提升的化学教学进行分析和阐释。  相似文献   

7.
郭浩芳 《化学教育》2012,33(3):36-37
针对高考化学卷试题和学生的考试情况,反思高三一年的教学,剖析化学高考复习3大误区:教学内容机械重复;教学手段因袭陈旧;复习缺少人性关怀。  相似文献   

8.
邓阳  王后雄 《化学教育》2010,31(12):48-51
利用二段式测验准确诊断高三化学复习中学生的迷思概念对于教师顺利实施概念转变教学、选择适当的复习教学策略、提高高三复习效益有着重要的意义。详述了二段式测验题的类型、编制、施测和分析方法,并结合具体教学实例(化学平衡)讨论如何利用二段式测验诊断高三化学复习中学生的迷思概念。  相似文献   

9.
优化教学程序 提高高考化学复习的效度   总被引:1,自引:0,他引:1  
王愫懿 《化学教育》2010,31(9):47-49
从如何解读《考试说明》,严控高三化学复习的范围;如何研究近两年全国各地的高考试题,提高高三化学复习的针对性;如何捕捉学生的化学知识薄弱点与盲点;如何提高高三化学复习课的效度;如何狠抓“三化”,提高学生的答题效率与成功率等方面介绍了进行高考复习的成功经验。  相似文献   

10.
《普通高中化学课程标准(2017年版)》构建了化学学科核心素养的内容体系及其发展水平框架,重视开展“素养为本”的教学,重视真实情境的创设。在分析教学情境的内涵与功能的基础上,解读了新课标中课程内容、实施建议和命题原则中对真实情境创设与应用的要求,讨论了真实情境在发展学生化学学科核心素养中的教育价值。通过对具体教学案例的分析,探讨了基于学生化学学科核心素养发展的教学情境设计的策略。  相似文献   

11.
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.  相似文献   

12.
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。  相似文献   

13.

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.

  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
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^-。  相似文献   

17.
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.  相似文献   

18.
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, Mo, 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 600-700oC. 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.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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