The article introduced the discovery of calcium element as well as its application in the field of building materials, including the history, production process, and technical innovation. Moreover, based on his research experiences, the author also reported the development of calcium building materials in the field of nanocomposite.

The German chemist Johann Wolfgang Döbereiner proposed his triad theory of elements in 1829, which is considered as the first effort towards the discovery of the periodic system of elements. He also made excellent achievements in many other areas of chemistry. The year 2019 is not only the International Year of the Periodic Table of Chemical Elements, but also the 170th anniversary of the death of this great chemist. This article aims to give a detailed overview about Döbereiner.

Advanced analysis techniques are important tools for revealing the micro world. It is also important for students to learn micro scale dimension. Contrary to that of the traditional optical microscopy and electronic microscopy, the observation of the morphology of a sample by atomic force microscopy is based on the atomic force interaction between the tip and the sample. This article briefly describes the basic principle and basic structure of atomic force microscopy, and explains its core components and functions. There are four main operating modes for atomic force microscopy. This article compares their advantages and disadvantages and their applications. Finally, the practical application of atomic force microscopy in analysis is briefly described, demonstrating the superiority and broad application prospects of atomic force microscopy.

Flexible lithium-ion battery is an emerging lithium-ion battery, which has the same working principle with the conventional lithium ion battery. However, it uses the flexible current collector, which endows it flexible, bendable, stretchable characteristics, thus being a power source for flexible/wearable devices. Herein, we introduce two ways to realize flexible lithium-ion battery, on one hand, developing various conductive current collectors (including carbon nanotube, graphene and carbon cloth)-based flexible lithium-ion battery, on the other hand, designing and constructing flexible lithium-ion battery with new structures (including cable/wire type, transparent and stretchable).

This paper explored the flipped classroom of inorganic chemistry teaching for material major freshman based on micro-course videos, and the implementation effect was evaluated by examination results and Likert 5 scale questionnaire scores. It was found that after 36 school hours of inorganic chemistry teaching, the scores of the students in the experimental class were significantly higher than those in the control class, and the rate of failure was lower. The scores of most index questionnaires in the three dimensions of knowledge and skills, process and method, attitude, emotion and values were significantly higher than those in the control class. It was showed that the students' learning effect was improved as well as their learning attitude and ability, and the students' learning process was optimized. The above results are analyzed in detail, and the suggestions for further application of flipping classroom in inorganic chemistry teaching in colleges and universities are put forward.

Inorganic chemistry of elements is a key course of chemistry and relative specialities in universities. How to teach well and to learn well inorganic chemistry of elements has been being a research project of educators in inorganic chemistry. An idea of integration of knowledge of inorganic chemistry of elements is proposed in this article in order to change teaching status, improve teaching effect and cultivate students' abilities of logical thinking and scientific innovation. The chapter of oxide is as an example to show how to carry out this more systemic knowledge integration of inorganic chemistry of elements based on the types of compounds.

In this paper, we propose to replace or supplement the traditional offline exercises teaching by using online teaching mode with both micro-lesson video and autonomous learning guide. We explore the method of determining the stratified teaching difficult point in the micro-lesson design. Taking a common fallibility electrochemical exercise as an example,we introduce the teaching design and procedure in the exercises type micro-lesson. The exercise involves teaching important and difficult point listed below, the design of the battery and the writing of the cell notation, the calculation of the standard electromotive force and the standard equilibrium constant. The teaching practice shows that the method of using the micro-lesson teaching mode to perform the homework wrong analysis can make up the problem of insufficient class hour of the traditional college chemistry. It is also suitable for the students with different level and beneficial to the student's extending and innovative learning.

Inspired by the U-shaped seven-step discussion method of the private board of directors, the author proposes a new method that can be applied to research-oriented teaching and studying, U-type seven-step inquiry method. The "U-type" means that the problem exploration has a process of first sinking to find the essence and then flouting out to clarify the problem. The seven-step discussion method includes specific processes such as questioning and exploring. The inquiry is guided by the coach and centred on the owner of the case, and then benefits the entire staff. This article also gives a detailed explanation of the method with a successful operation example.

The preparation experiment of polymeric ferric sulfate was improved. Considering dosages of hydrogen peroxide, concentrated sulfuric acid and water, synthesis temperature are the four most influential factors for the preparation of polymeric ferric sulfate, these four factors were changed into variables. The orthogonal test with four factors and three levels was carried out by students, and then the best conditions for preparation were obtained by comparing to the rate of turbidity. The improved experiment not only improved the students' ability of exploration, but also deepened the students' grasp of the preparation conditions of polymeric ferric sulfate.

The experiments of an elective chemicals course "Fin chemicals" are re-examined and redesigned because of the poor enthusiasm of the students during their experiments, which makes the teaching results unsatisfactory. To make students understand the way of a theory being converted into a feasible implementation plan, the students are needed to take part in the whole process of the redesigned experiments, which includes the content development, experiment operation and the result discussion. The students are required to participate in the second experiment in a progressive style,which is a chance to make up for the deficiency in their first experiment and to understand the huge impact of tiny changes in a process to the experiment result. It shows the student-centered adjustment can make the students care about the details during experiment and follow the reason of experiment failure, which helps them to correct their errors timely in the second trial. This exploration on experimental teaching provides a way to the cultivation of students' comprehensive quality.

Basic copper carbonate preparation experiment is a representative comprehensive design experiment, which is always set up in inorganic chemistry experiment course for university freshmen. While the experiment results of most students were not so ideal, such as the sample's color was too bluish or the weight was too low, etc. In order to get better results in teaching, the preparation conditions including reactants ratio, react temperature, the order of reactant adding and the order of blending and heating were studied in this paper. The samples were analyzed by XRD and FT-IR. Results indicated that green pure phase basic copper carbonate were prepared at the conditions that molar ratio of CuSO₄ to Na₂CO₃ was 1:1.2, the Na₂CO₃ solution was added into CuSO₄ solution, and then heated at 75℃ for 15 minutes.

This paper designed a comprehensive experiment including analytical chemistry, inorganic chemistry, organic chemistry, and physical chemistry. Firstly, this experiment prepared ZSM-5 zeolite which was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and physical adsorption. The change of ZSM-5 in experiment was quantitatively correlated with the structure, surface topography and pores size distribution. Thereafter, the effect of pH, adsorption time, adsorption temperature, and ZSM-5 content on the adsorption of Cu²⁺ was studied. This experiment involved the synthesis theory of inorganic and organic chemistry, the surface adsorption principle in physical chemistry and the application of analysis methods of analytical chemistry. Meanwhile, the use of data processing methods and large-scale instruments could not only exercise the practical operating ability for students, but also improve the ability to analyze the experimental data and results evaluation for students.

This experiment, coming from teachers' scientific research, can synthesize a new compound 4,4'-dipyridine (2Py-TPE) with aggregation-induced emission (AIE) property by two simple steps (condensation and Suzuki reaction) in order to enhance the students' experimental operation and innovative ability. The target compound was purified by the common organic separation means, such as filtration, washing, extraction, drying and column chromatography. The characterization and AIE property of the compound was investigated by NMR, high-resolution mass spectrometry, infrared spectroscopy and transient fluorescence spectroscopy. This experiment can not only help students understand the research status of AIE materials based on tetraphenylethylene, but also cultivate students' comprehensive experimental ability and scientific research ability.

In order to find effective strategies for training normal university students' classroom teaching behavior, we conducted an education experiment to 38 students in a normal university, discussed the influence of training strategy of teacher one-way coaching and peer reciprocal coaching on the change of classroom teaching behavior of normal university students. Results show that compared with teacher one-way training strategy, peer reciprocal coaching can stimulate the initiative of all students. So peer reciprocal coaching is a kind of low consumption and high efficiency of effective strategies for training normal university students' teaching basic skills.

Reflection is an important way for pre-service teachers to learn. We choose a representative reflective pre-service chemistry teacher Y as our research case, and collect reflection texts in her blog for inductive analysis. Her pre-employment growth in five stages are sorted out:reflection on the enlightenment stage, the study and practice stage, the deep accumulation stage, the metamorphosis stage, and the education practice stage. Each stage of growth reflection is based on different stages of learning behavior or practical actions, and requires certain key events to trigger. By analyzing the text of her blog, we summarize her reflection path mainly through four forms of lecture notes, teaching reflection, reading notes, life essays, and find that "important others" including studio tutors, famous teachers from middle school and like-minded student teachers affect her pre-employment growth.

Taking the course of organic chemistry as an example, this article discussed the construction and practice of the anchored flipped classroom teaching mode. It mainly included the production of micro-lesson video before the class, the organization of a class, the development and tutoring after the class, and teaching evaluation. Anchored teaching mode and flipped classroom could arouse the initiative and enthusiasm of the students and make the students become a principal part in the course study. It is beneficial to the teaching of organic chemistry courses and it helps to cultivate more and better talents in the new age of pharmacy.

The reform of evaluation method in college chemistry was carried out. A process-oriented assessment was applied in the course. The percent of final exam score was decreased in the total score. More homework was required to enhance basic learning and help to improve ability to judge and solve practical problem. So that is required students to study actively and avoid cram session. The questionnaire survey showed that most of students can accept the evaluation method.

Due to the diversity of the valence electrons and the coordinated atoms in the central atom of the covalent molecule, the criteria for identifying equivalent and nonequivalent hybridization from different versions of domestic textbooks are not uniform. This article discussed the advantages and disadvantages of the two distinguishing criteria that are commonly used in domestic textbooks. Based on the reasons why the concept of hybridization was presented, and referring to the approaches of foreign textbooks, this paper proposed a suggestion that we should not distinguish between equivalent and nonequivalent hybridization.