This study has summarized the allotropes of tin from bulk materials to typical emerging nanomaterials (stanene and Sn quantum dots) including their structures, preparations, properties, applications. The discussion enhances the study of allotropes in inorganic metals.

Rare earth elements have important strategic value in science and technology, industry and national defense system. The flotation capture reagents of rare earth ore are very crucial for rare earth smelting and the effective utilization. A brief introduction to the research on coordination effect in flotation capture reagents is presented in this paper. The correlation among the structures and selections of flotation capture reagents and the mechanism of rare earth elements is further clarified.

A continuous improvement evaluation mechanism from teaching management to curriculum is implemented under the concept of continuous improvement. Although process assessment is widely used in curriculum evaluation, there are some deficiencies such as emphasizing form over feedback and focusing on results over improvement. This article constructs a PDCA cycle mode of curriculum assessment system of the “teaching objectives-teaching implementation-teaching assessment-teaching improvement” based on quality management methods. The characteristics of this mode are: firstly, achieving consistency in learning objectives, teaching activities and evaluation; secondly, the evaluation cycle of “faculty evaluation-peer assessment-self assessment-improvement” achieves iterative growth assessment; thirdly, the teaching cycle of “pre-test-instruction-internalization-consolidation” ensures the alignment and achievement of teaching objectives; fourthly, the “review and reflection” stimulates learning interest and enhances intrinsic motivation. Practice has shown that the PDCA cycle mode of the teaching evaluation system provides an effective pathway for the implementation of the continuous improvement concept in curriculums.

Teaching evaluation is an important link in teaching management. There are often uncertainties and differences in university teaching evaluation,which makes the teaching evaluation results not enough truly reflect the teaching reality, thus can not really play the incentive role of evaluation, and even hinder the improvement of teaching quality. On the basis of introducing the Grubbs rule, this paper takes Analytical Chemistry for example to verify the uncertainty and difference of teaching evaluation, and uses mathematical statistics Grubbs test method and mathematical modeling method to analyze and discuss the uncertainty and difference of teaching evaluation of Analytical Chemistry, and to research and solve the deviation caused by evaluation data. By scientifically processing data and correcting unreasonable evaluation data, to ensure that teaching evaluation is true, fair, and effective.

Through the implementation of the process assessment concept and the careful designing of the examination content, using multiple test mode, including unit test + stage test, online test + offline test, with the means of appreciation education, the teaching reform exploration of English chemistry specialty course was completed. Together with the enhancement of confidence of the students, the goal of “promoting learning by examination” was realized, so that the students wound learn with pressure and motivation, and obtain an efficient and obvious improvement on teaching effect.

By designing effective scientific issues, students use computational chemistry techniques to obtain the data, and apply the theoretical knowledge of structural chemistry to analyze, interpret, and summarize the data, and then clarify the scientific issues. In this way, the scientific issues drive the series understanding of the core knowledge points in structural chemistry. For students, they can learn deeply and understand the theoretical knowledge of structural chemistry. At the same time, this greatly improves their ability to analyze and demonstrate questions, and enhance their learning initiative.

Based on the ADDIE mode, the author established an integrated analytical chemistry ideological and political mode for analysis, design, development, implementation and evaluation. Focusing on the four themes of “social service, scientific development, professional ethics, and philosophical speculation”, 17 cases and 8 philosophical principles were selected and integrated into the teaching. A long-term ideological and political education method of “instruction before class-internalization in class-extension after class” was constructed. The Minnesota Short Form Scale was used for evaluate the effectiveness of education. The application of the ADDIE mode improved the quality and efficiency of analytical chemistry teaching, promoted the advancement of knowledge and ability, and realized value guidance for students.

In this paper, the deficiencies in the experiment of determining total iron content by potassium dichromate titration are improved, and a mercury-free iron determination method based on SnCl₂-I₂-AgCl pretreatment is explored. The improved experiment involves major knowledge of the four chemical equilibrium theories. The method has better reproducibility, environmental friendliness, low cost, and has achieved good teaching results.

In the experiment of determining the saponification kinetics of ethyl acetate by conductivity method, the different results were obtained by different data processing methods. Based on the original experimental data of 31 groups from students, the linear, nonlinear and exponential function programs were used to fit .Then,the measurement, calculation results and correlation coefficient of the original data were compared.It was indicted that the results from the latter two methods are close and better than the first method. Moreover, the exponential fitting method can achieve the fitting effect with smaller standard deviation of activation energy. Therefore the accuracy of analysis results and the application ability computer software by students can be improved via the variety of data analysis methods.

Aiming at the problem that alum was easy to lose water in the inorganic chemistry experiment “preparation of alum”, we used thermal gravimetric analyzer to heat and analyze the pure alum in different temperatures, then the sample (KAl(SO₄)₂) after heat treatment at 300 ℃ was taken for rehydration experiment. The samples were characterized by X-ray powder diffraction (XRD), and the structural change between alum dehydration and rehydration after heat treatment was explored. Through theoretical calculation and combined with the crystal microstructure of the material, the reason why alum was easy to lose water was clarified, and the mechanism of water loss and rehydration of alum was analyzed, which can provide a detailed theoretical basis for explaining the phenomenon of teaching experiment.

The course “Educational Research Methods” offered by chemistry teachers emphasizes the integration of moral education and creative education. Firstly, the course content incorporates cutting-edge issues, continuously highlighting dynamic generation and demonstrating the pursuit of innovative development direction; Secondly, the curriculum strengthens the process orientation of teacher-student interaction and project-based learning experience; In addition, the curriculum focuses on resource construction and post class self media dissemination to promote the integration of moral education and creative education as an educational approach. Finally, a teaching design case of “content analysis method” was provided to demonstrate the specific operation of integrating moral education and creative education in the teaching process.

The online and offline blended teaching practice of the chapter “saccharides” in the organic chemistry of medicine and related majors was introduced. Under the background of the full penetration of educational information technology into college classrooms and under the guidance of the curriculum concept of “curriculum ideology and politics”, the ideological and political elements of the courses were organically integrated with the teaching content, and diversified teaching methods were used to promote students’ scientific inquiry awareness in the process of knowledge learning. The teaching practice of promoting students to deeply understand the connotation of knowledge, experience the scientific thinking and spiritual value deduced by knowledge, and cultivate scientific literacy and social responsibility awareness was explored.

Taking engineering materials course as an example, this paper discusses the construction and application of the teaching system of public basic course of materials for engineering students. The curriculum system builds targeted interactive cases, and takes this as the core through the teaching design of “one body and two wings”. Among them, “one body” refers to the cultivation target of material professionals as the main body; “Two wings” refers to the teaching hardware integrating network platform, smart classroom and smart phone (one wing: teaching infrastructure) and participatory learning, in-class testing and teaching adjustment based on instructional design (one wing: teaching resources and teaching practices). Therefore, accurate teaching guidance can be implemented according to process learning feedback, and in-depth interaction can be carried out in learning disabilities. The reform results based on the above theoretical framework show that students’ learning initiative, course participation depth and comprehensive ability have been improved, and this teaching method can be further popularized and applied.

Anaerobic digestion (AD) is an important pathway of organic matter degradation in nature, which is of great significance for achieving environmental and economic sustainability. AD involves so many biochemical reactions that it is difficult to accurately describe the reaction pattern of methane production. The teacher introduced the methanogenic kinetics into Biochemistry teaching by designing five closely connected teaching modules. After introducing the derivation process, applicable scope, and parameter characteristics of three common methanogenic kinetic models, students were then taught how to use software to perform data fitting and trained to analyze the simulated results. By introducing methanogenic kinetics into teaching, students can not only better understand the basic knowledge of complex AD process but also learn a method for describing the methanogenic process accurately and quantitatively, thus building a bridge between theory and practical application. This teaching innovation laid a foundation for students’ participation in future engineering practice and achieved good results. This paper can not only have great significance for improving the teaching framework and quality of Biochemistry course but also provide a useful reference for the teaching reform of other related courses in Environmental Engineering, Chemical Engineering, New Energy Engineering, and Biological Engineering majors.

The integration of the disaster and ethical education into the medical chemistry is an important way to improve students’ awareness of epidemic prevention. Taking the teaching reform and practice of medical chemistry as an example, this paper analyzes the methods, means, ways and effects of integrating medical chemistry into disaster ethics education. The ethics education of disaster and epidemic is integrated into medical chemistry course, which makes students feel the ethics education of epidemic and fully arouse their initiative to achieve better learning effect.

Polymerization-depolymerization equilibrium and ceiling temperature of vinyl monomer are two important thermodynamic questions in polymer chemistry. A new approach treating the polymerization-depolymerization equilibrium of vinyl monomer is developed based on the overall reaction rather than the elementary propagation reaction, with new equations being derived, new definition of ceiling temperature (T_c) being established, and typical examples being given, which can explain the effects of dissolution and concentration of the produced polymer in its monomer on the equilibrium for monomers giving soluble polymers, that were all ignored in Dainton and Ivin’s approach. Also, the concepts of neutral equilibrium and stable equilibrium are introduced. This approach and its conclusion are also applicable to ring-opening polymerization of cyclic monomers.

Instrumental analysis courses involve a wide range of knowledge, high level of difficulty difficulty in understanding, and high requirement of practical skills. Therefore, it is worth exploring how to introduce new perspectives to refine and consolidate teaching content, and enhance learning effectiveness. From the perspective of the “calibration curve”, this paper intuitively explains the definition of the analytical performance parameters and their relationship such as sensitivity, characteristic concentration, characteristic quality, limit of detection, and limit of quantitation. It summarizes the types of interference in instrumental analysis and their elimination methods using the calibration curve as the integration point, explores their commonalities and essence, proposes the approaches and strategies, and provides a new perspective of “numerical and graphical integration” and “application-oriented” for the learning of instrumental analysis courses. This perspective helps to integrate key knowledge points and cultivate students’ awareness and thinking methods of “learning for application”.

According to the textual research and analysis of the development process of the concept of cadmium, at the beginning of the 19th century, with the development of scientific ideas and chemical analysis methods, German chemist Stromeyer first made and named cadmium through drug analysis. In 1826, Swedish chemist Bezelius measured the atomic mass of cadmium for the first time, giving cadmium a new meaning. The determination of the atomic mass of cadmium and the formation of the periodic table of elements combine the concept of cadmium and cadmium atoms. In 1924, British chemist Aston discovered cadmium isotopes through a mass spectrometer, forming the modern concept of cadmium. In short, with the continuous development of scientific ideas and methods, the connotation of the concept of cadmium is also constantly evolving and changing.