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复习教学在中学化学教学中有着重要的地位,对学生化学学习起着总结、提升的作用,是提高教学质量的重要环节。针对传统高中化学复习教学中存在的问题,尝试以“课程内容主题化、主题内容情境化、情境内容问题化、情境问题解决互动化、能力迁移与知识活化”的主题教学复习方法,解决教学中的问题,提高化学复习效益。 相似文献
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转变初中化学复习课的教学方式,以真实情境为载体,确定“探索蒸汽眼罩的奥秘”为项目主题,引导初中学生深入开展铁元素的专题复习。详细阐述了教师对该部分内容教学的课前分析,如何确立、规划和实施项目。学生通过完成“设计实验方案证明铁的存在”“探究活性炭和氯化钠对铁生锈的影响”等2个任务,提升了学科兴趣,对铁的性质进行了系统性再造。通过手持技术监测氧浓度和温度变化探究眼罩成分的作用,学生的科学探究能力从定性过渡到定量,实现了科学探究素养的深化与进阶;通过观看科普视频了解前沿科学,拓宽了学生的生涯认知,涵养了科学精神。 相似文献
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基于深度学习理念,以“常见高分子材料的用途与合成”为学习主题,开展关于有机合成复习课的教学实践。指出在有机合成的复习课,开展深度学习有利于激发学生的学习需求、调动学生高阶思维、让学生迁移运用所学知识。基于深度学习的教学设计需要把握挑战性学习主题、深度学习目标、深度学习活动和持续性评价4大要素。提出课前应引导学生开展挑战性学习主题的项目调研;课上应创设引导学生深度学习的问题情境,促进学生高阶思维的发展;课后应让学生以思维导图的形式理顺有机合成的一般方法等,为教师开展基于深度学习的教学实践提供参考。 相似文献
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以"常见酸式盐"复习课为素材,以分类观、离子反应和氧化还原理论为指导,以真实问题为背景,以实验探究为手段,为如何整理零散元素化合物知识及研究物质性质提供了范例。 相似文献
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概述了"实验-性质-原理"三元整合策略的内涵及在高三化学微专题复习中的实施应用。以"弱电解质的电离与电离平衡"为例,以"区别相同浓度的盐酸、醋酸"实验探究活动为驱动任务,结合盐酸、醋酸与镁反应不同时间段的现象,学生根据反应原理预测可能原因,画图分析c(H+)变化,完成强、弱电解质性质的"宏观-微观-符号"三重表征。引入电离平衡常数的数据分析活动,穿插"原因解释"的答题策略及规范训练、图表阅读、基于控制变量法设计实验方案等学习任务,为高三微专题复习提出教学建议。 相似文献
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分析了“铁的性质和冶炼”复习教学中的2个问题:未注重实验室与工业生产流程对比,缺乏真实的认知体验;只重视知识的概括和重组,缺乏基于实证的科学探究和思辨后的知识重构。设计真实的生产场景让学生感知化学的社会价值,在科学实验场景中探寻化学的本体价值,同时将化学的育人价值贯穿教学过程。 相似文献
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寓"化石燃料与有机化合物"复习于苯乙烯和乙苯的性质探究中,以此激发学生的复习兴趣,提升"化石燃料与有机化合物"复习教学的有效性。同时使学生建立"结构决定性质、性质反映结构"的化学思想,以及在此思想指导下领会分析和研究化学问题的基本方法。 相似文献
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对“原电池的工作原理”进行了教材分析、学情分析,在必修2学习的基础上,结合生活实际设计了4个教学环节:通过生活中的原电池和必修知识的复习,引出原电池原理;通过铜锌原电池的设计、分析,掌握单液原电池原理;从原电池的能量转化效率出发,学习双液原电池原理;利用原电池的形成条件,设计原电池。 相似文献
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本文是《分析试验室》定期评述中“化工、石油产品及硅酸盐分析”课题的第七次评述,评述了1997 年7 月至1999 年6 月国内关于化工产品、石油产品、硅酸盐的分析进展,引用文献709 篇。 相似文献
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Alan Quintal Eugenia Dzib Fernando Murillo Filiberto Ortíz-Chi Israel Fernández Gabriel Merino 《International journal of quantum chemistry》2024,124(1):e27194
Analyzing activation strain, energy decomposition, and reaction force models is crucial for studying chemical reactivity and gaining quantitative insights into the factors that control energy barriers. However, manually preparing and processing the necessary data can be challenging and prone to errors. To address this issue, we introduce SurfinPES, a Python-based module in Eyringpy that automates data extraction and processing for these analyses. SurfinPES also allows monitoring of the evolution of primitive properties (geometrical and electronic) along the reaction coordinate. The module is user-friendly with a simple input format, making it accessible to any user in the field of computational chemistry. 相似文献
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The aim of the present study was to determine the kinetic equations for the thermal transformations of precipitated iron oxides
and hydroxides, namely for the process of thermal dehydroxylation of goethite and consecutive of hematite crystal structure
growth as well as for the oxidation of magnetite to maghemite and its thermal transformation into crystalline hematite. The
investigations have been carried out using thermogravimetry (TG/DTG/DTA), X-ray powder diffractometry (XRD) and high temperature
powder diffractometry (HT-XRD). This presentation contains the continuation of our earlier works.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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化工,石油产品及硅酸盐分析 总被引:2,自引:2,他引:0
本文是《分析试验室》定期评述中“化工、石油产品分析“课题的第四次评述,它评述了1991年7月至1993年6月国内关于化工产品分析、石油产品分析、硅酸盐分析及我国化工、石油产品标准的进展,共引用文献642篇。 相似文献
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E. Rudnik 《Journal of Thermal Analysis and Calorimetry》1997,49(1):465-469
The results of computational modeling and experimental data on some thermophysical properties of selected polymers were compared. Different engineering polymers, e.g. polycarbonates and terephthalate polyesters, were considered and their glass transition temperatures and thermal stabilities were determined, by using thermoanalytical methods, e.g. DSC and TG. Measurements were carried out with Perkin-Elmer DSC 7 and TGA 7 instruments. Molecular modeling and computer calculations were performed at the Interdisciplinary Computer Modeling Center (ICM) of Warsaw University, using a Cray El 98 computer and the Insight II software of BIOSYM Technologies Inc. Reasonably good agreement was found between the experimental and calculated values of the glass transition temperatures of the investigated polymers, e.g. for poly(butylene terephthalate)T
g (calc.)=74C andT
g (experim.)=70C. Discrepancies were observed for the temperature of half decompositionT
d,1/2, some of them can be explained by effects of polymer molecular weight and/or char-forming effects.Polymer modeling computations were performed at the Interdisciplinary Computer Modeling Center (ICM) of the Warsaw University, where a CRAY EL 98 computer and the software of BIOSYM Technologies, Inc. were used. 相似文献
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W. Hoppe 《Angewandte Chemie (International ed. in English)》1966,5(3):267-280
The extent to which it is possible to automate the determination of a structure from the data collected with automatic measuring equipment is discussed. The development of the automatic evaluation is synchronous with that of digital computer program.—Even the simple calculation of structure factors from the intensities (i.e. the analysis of the geometrical and physical intensity factors) takes several weeks when the many thousand reflections are processed “manually”, i.e. with a desk calculator. A large electronic computer, on the other hand, executes these calculations in a few seconds. Nevertheless, even the largest computers available at present are too small for many of the complex steps in the calculation and for the quantity of data involved. Evaluation methods which, owing to long computing times, can at present only be tested on relatively simple structures will become more attractive with the advent of machines with computing times in the nanosecond range. For corrigendum see DOI: 10.1002/anie.196605112 相似文献
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A critical comparison of the various PCA methods on the absorbance matrix data concerning the complexation equilibria between SNAZOXS and Cd2+, Co2+, Cu2+, Ni2+, Pb2+ and Zn2+ or Naphtylazoxine 6S and Cd2+, Cu2+, Ni2+ and Zn2+ at 25 °C is performed. The number of complex species in a complex-forming equilibria mixture is the first important step for further qualitative and quantitative analysis in all forms of spectral data treatment. Therefore, the accuracy of the nine selected index functions for the prediction of the number of light-absorbing components that contribute to a set of spectra is critically tested using the principal component PCA algorithm INDICES in S-Plus software. Four precise methods based upon a knowledge of the experimental error of the absorbance data and five approximate methods requiring no such knowledge are discussed. Precise methods always predict the correct number of components even a presence of the minor species in mixture. Due to the large variations in the index values and even at logarithmic scale they do not reach an obvious point where the slope changes. An improved identification with the second or third derivative and derivative ratio function for some indices is preferred. Behind the number of various complexes formed the stability constants of species ML, ML2, (and ML3, respectively) type log β11, log β12, (and log β13, respectively) for the system of SNAZOXS (ligand L) with six metals (the standard deviation s(log βpq) of the last valid digits are in brackets) Cd2+ (4.50(3), 8.36(7)), Co2+ (5.75(6), 9.79(9), 13.05(2)), Cu2+ (6.69(6), 11.40(7)), Ni2+ (6.44(8), 10.91(11), 15.07(10)), Pb2+ (5.63(5), 9.97(9)) and Zn2+ (5.11(3), 8.84(5)) and for system of Naphtylazoxine 6S with Cd2+ (6.08(4), 11.44(7), 16.06(11)), Cu2+ (7.80(8), 13.41(14)), Ni2+ (6.35(12), 11.43(19), 16.68(24)) and Zn2+ (7.01(8), 12.65(15)) at 25 °C are estimated with SQUAD(84) nonlinear regression of the mole-ratio spectrophotometric data. The proposed strategy of an efficient experimentation in a stability constants determination, followed by a computational strategy, is presented with goodness-of-fit tests and various regression diagnostics able to prove the reliability of the chemical model proposed. 相似文献
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植物类中药中微量元素的因子分析和聚类分析 总被引:40,自引:0,他引:40
尝试利用化学计量学方法探讨微量元素含量与中药药性的相关性。对105味植物类中药42种微量元素测定数据用因子分析和聚类分析进行了多因素分析。因子分析证实了一个10因子模型合理解释这些微量元素间的相关关系;样本聚类分析证明了105株中药合理地聚类成不同组; 相似文献