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951.
构建课程新体系和改革教学内容是高等教育改革永恒的主题。本文立足于地方综合性大学的特点,通过构建"四位一体"课程新体系,形成三层次的课程模块,进行多角度、多层面的课程内容改革,为化学创新型人才的培养奠定了基础。  相似文献   
952.
The laboratory teaching plays more important role for improving the students' scientific literacy according to the progress of the modern society. To provide enough scientific training opportunities, the usual technology and methods used in physical chemistry research field were introduced into the physical chemistry laboratory teaching.  相似文献   
953.
李英  丁伟 《化学教育》2018,39(15):68-72
铁离子和硫氰化钾反应生成稳定的血红色络合物硫氰化铁,用智能手机拍摄所得图像的颜色反映在图像的RGB值上。随着该溶液浓度的增大,溶液颜色逐渐加深,反映在拍摄的图像中颜色的RGB值也在变化,并且得出该溶液颜色的R值与溶液的浓度成线性关系。结果显示,用该实验方法测得的抗贫血药物中铁的含量与用紫外分光光度法测得同一药品中铁的含量相比误差为5%;并且该实验方法在中学的化学实验课中很容易实现,避免了学生用目视比色法测量抗贫血药物中铁的含量时因标准溶液的色阶选择不合适而导致实验的失败。  相似文献   
954.
郑长龙 《化学教育》2018,39(9):41-47
对2017年版普通高中化学课程标准中化学学科的本质及价值、化学学科核心素养的内涵及结构、化学课程内容体系和“素养为本”化学课堂教学的设计等重大变化进行了解析。  相似文献   
955.
《先进技术聚合物》2018,29(8):2336-2343
Morphology structure and interfacial interaction are crucial factors for shape memory thermoplastic vulcanizates. In this study, shape memory thermoplastic vulcanizates based on poly(lactic acid) (PLA) and nitrile butadiene rubber (NBR) were prepared through dynamic vulcanization. The influence of acrylonitrile (ACN) content on the morphology, compatibility, shape memory property, and mechanical property was investigated. A co‐continuous structure was observed. The interfacial compatibilization between PLA and NBR phases occurred, resulting in a significantly improved interface adhesion and interfacial interaction, which was confirmed by Fourier transform infrared spectroscopy. With such a novel structure, the PLA/NBR TPVs owned an excellent shape memory property and further improved with increasing ACN content of NBR, which could be explained that the cross‐linked continuous NBR phase provided a stronger recovery driving force. In the meantime, tensile strength and elongation at break of TPVs increased with increase in ACN content. It is concluded that the preparation of dynamically vulcanized thermoplastic vulcanizate with co‐continuous structure and strong interfacial adhesion is beneficial to obtain outstanding shape memory effect.  相似文献   
956.
Calorimetric measurements were carried out on the electrorefining of copper using different current densities with a Calvet type microcalorimeter at room temperature. The ratio (R) of the measured heat (Q m orW m) to the input electric energy (Q in orW in) and the excess heat (Q ex orW ex), i.e. the difference betweenQ m (orW m) andQ in (orW in) during the electrorefining process were discussed in terms of general thermodynamics. It was found thatR andQ ex were related to the current density employed in the experiment and varied as a logarithmic function. The results obtained here indicate that the heat generation under different conditions, such as different currents or voltages, may be caused partially by the irreversibility of the process or by some unknown processes.Dedicated to Prof. Menachem Steinberg on the occasion of his 65th birthdayThe authors would like to acknowledge the extreme encouragements and help of Professor Shuyi Liu (University of Science and Technology of China) and Professors Fu Tan and Guoquan Liu (Institute of Chemistry, Academia Sinica).This study was supported by the National Nature Science Foundation of China.  相似文献   
957.
The main goal of the paper is to give explicit formulas for the fundamental classes of Schubert subschemes in Lagrangian and orthogonal Grassmannians of maximal isotropic subbundles as well as some globalizations of them. The used geometric tools overlap appropriate desingularizations of such Schubert subschemes and Gysin maps for such Grassmannian bundles. The main algebraic tools are provided by the families of and -polynomials introduced and investigated in the present paper. The key technical result of the paper is the computation of the class of the (relative) diagonal in isotropic Grassmannian bundles based on the orthogonality property of and polynomials. Some relationships with quaternionic Schubert varieties and Schubert polynomials for classical groups are also discussed.  相似文献   
958.
A generalization of I. Dobrakov's integral to complete bornological locally convex spaces is given.  相似文献   
959.
The problem of estimating diffusion coefficients has been considered extensively in both discrete and continuous time. We consider here an approach based on counting occupation numbers of diffusing particles. The problem, and our approach, are motivated by statistical mechanics.  相似文献   
960.
In this paper, we work with lattice spaces. (A lattice space is an ordered pair consisting of a set X and a lattice on X). As is known, each lattice measure µ induces six outer measures on P(X), one of which is the well-known "induced outer measure" µ*(in case µ is countably additive); the others are µ, µ, µ,, and .In the first part of the paper, we consider an arbitrary lattice measure and discover various relationships involving two or more of the seven set functions under consideration, on P(X) and on various special subsets of P(X), under various conditions on the measure or on the lattice.In the second part of the paper, we consider two lattice measures related by "domination" and obtain similar results.In the third part of the paper, we consider two lattice measures related by "restriction" and obtain similar results.  相似文献   
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