问题式教学和案例教学在普通化学教学中的综合应用——自发热贴发热原理中的基础化学

In this article, the topic of "chemical principles in warmer pad" is used as an example to illustrate how problem-based learning (PBL) and case learning (CL) are used in the teaching of general chemistry. We take the advantages of PBL to arouse the studying interests of students in the casing learning atmosphere. Moreover, the teacher leads the discussion. By using these two teaching methods properly, students' active learning ability, the skills of analyzing and solving problems, as well as the comprehensive practical ability can be improved.     

Flood search under the California Split rule

We consider flood search on a line and show that no algorithm can achieve an average-case competitive ratio of less than 4 when compared to the optimal off-line algorithm. We also demonstrate that the optimal scanning sequences are described by simple recursive relationships that yield surprisingly complex behavior related to Hamiltonian chaos.     

On the Non Linear Behaviour of Nematic Liquid Single Crystal Elastomers (NLSCE) Under Biaxial Mechanic and Electrical Force Fields

A continuum theory has been developed to give account of the three characteristic zones appearing in the “semisoft” behaviour of nematic single crystal elastomers under the effect of biaxial mechanic and electrical force fields considering higher order coupling terms. The analysis is based on a model which takes into account two coexistent coupled components showing a preferred direction. Two cases are analysed according to the type of input: stress and displacement. Bifurcation phenomena are predicted in the first case. Sress-strain curves show the characteristic features experimentally observed. The case where shear terms in the strain are considered is approximately analysed.     

雨课堂背景下巧用案例法提高现代分析测试技术教学效果*

现代分析测试技术是工程类相关专业硕士研究生的必选课程,该课程传统的教学模式往往以教师讲授为主,学生实际操作的机会少,造成了学生学习积极性不高。和传统的教学模式相比,雨课堂增加了教师和学生间的沟通互动和课堂趣味性,有利于提高学生的课堂积极性。基于雨课堂,将教师的科研作为案例融入课堂教学,同时采用“打卡通关”式的案例教学模式,通过案例模拟实际测试,提供真实情境教学,激发学生学习兴趣,提高学生的课堂参与度,明显提高了该课程的学习效果。     

国外配位化学主题教学案例研究——Journalof Chemical Education近十年的载文分析

选取Journal of Chemical Education近十年来有关“配位化学”主题教学的载文,从文献栏目分布、关键词分析、教学案例类型的不同视角分析该主题的发文情况,并基于趣味活动、生产生活、模型教学、信息技术等4个维度介绍了具有代表性的教学案例。最后提出促进“配位化学”主题有效教学的研究建议,为我国“配位化学”主题教学研究及教师教学实践提供借鉴和参考。     

CBL结合学科思维导图在生物化学检验教学中的应用

为了培养高职高专检验专业学生在临床思维、问题探究及知识系统性掌握运用等方面的综合能力,在生物化学检验教学中探索了CBL与学科思维导图相结合的教学方法,多年的教学实践证明,这是一种可以用于提高学习者综合能力的良好的教学方法。     

促进深度学习的化学课堂教学案例研究

基于深度学习提出了相应的教学对策,并通过对创设真实情境、整合意义联接的学习内容、设计联系生产和生活的劣构迁移领域、设置留悬的批判空间、选择持续关注的评价方式等5个方面的案例分析,为培养学生的高阶思维,促进学生的深度学习提供一定借鉴。     

CALCULATION OF THE YOUNG''''S MODULUS OF AN ADSORBED POLYMER LAYER

Polymer layers adsorbed to a surface or in a confined environment often change their mechanical properties. There is even the possibility of solidification of the confined layer. To judge the stiffness of such a layer, we used the Hertz model to calculate the Young's modulus of the polymer layer in the confinement of AFM experiments with silicon nitride tip with a radius of curvature of R≈50 nm and a glass sphere attached to the cantilever R = 5μm. Since there is no visible indentation of the layer in the AFM experiments, the layer is either penetrated very easily, or the indentation is too small to be seen in a force curve. The latter would be the case for a polymer layer with a Young's modulus above 4×108 Pa in case of an experiment with a silicon nitride tip and 4×105 Pa in case of a glass sphere.     

Syntheses and Crystal Structures of Chiral BINOL Derivatives and Their Applications in Enantioselective Lewis Acid Catalyzed Addition of Diethylzinc to Aldehydes

Two novel chiral BINOL derivatives with bis(benzylamine) groups at the 3,3- positions have been synthesized through the condensation reaction between 2,2'-bis(methoxy- methyleneoxy)-1,1'-binaphthyl-3,3'-dicarboxylic acid and benzylamine or N-phenyl benzylamine in the presence of triethylamine. Suitable single crystal of (R)-N,N'-dibenzyl-2,2'-dihydroxy-1, 1'-binaphthly-3,3'-diformamide (R)-3 for X-ray diffraction was obtained by recrystallization at room temperature from the mixture solvents. Crystallographic data of (R)-3: C40H36N2O6, Mr = 640.71, monoclinic, space group P21, a = 6.746(3), b = 21.883(9), c = 11.723(5) , β = 104.605(7)°, Z = 2, V = 1674.7(12) 3, Dc = 1.271 g/cm3, F(000) = 676, R = 0.0729, wR = 0.1687 and μ(MoKα) = 0.086 mm-1. Two chiral BINOL ligands were found to be effective in the enantioselective addition of diethylzinc to aldehydes and much different enantioselectivity was observed both in the presence and absence of Ti(OiPr)4. In the former case, (R)-3 showed moderate enantioselectivity, which was lower than that of (R)-BINOL's; and in the latter case, (R)-4 gave the highest enan- tioselectivity up to 93.3% ee.*     

关于两类广义多项式的一些恒等式(英文)

By means of generating function and partial derivative methods, we investigate and establish several general summation formulas involving two classes of polynomials. The general results would apply to yield some identities for the Pell polynomials and Pell-Lucas polynomials, and other general polynomials can also be recovered in this paper.