This review focuses on the synthesis methods and application status of phosphocholine chloride and its derivatives and provides references for further expanding the application scope of phosphocholine chloride and its derivatives.

As a green and clean oxidant, it is very attractive to oxidize benzene with hydrogen peroxide to obtain phenol. In this paper, different kinds of heterogeneous catalysts, such as molecular sieves, carbon-based materials, metal oxides and metal organic frameworks for the oxidation of benzene to phenol with hydrogen peroxide are reviewed. The preparation routes, reaction mechanisms and catalytic performances are mainly discussed. It can provide a useful perspective for rational design of new heterogeneous catalysis.

In this paper, the allotropes of nitrogen are summarized and discussed according to the research progress on total-nitrogen substances. The allotropes of nitrogen are classified into four different kinds: molecular nitrogen, polymeric nitrogen, metal nitrogen and cluster nitrogen. The composition, structsure, existence, synthesis and application of various allotropes are discussed comprehensively. Thus, this paper can provide important materials for the teaching and research on element nitrogen.

Using an example of “emulsion polymerization of vinyl acetate”, a new teaching mode was researched to synergistically combine polymer chemistry theoretical and experimental courses. Synergistic teaching mode will overcome some drawbacks of conventional teaching in which theoretical teaching and experimental teaching are isolated as individual course, by systematical arrangement of theoretical, experimental and application teaching as a whole. The synergistical teaching mode includes the following contents: the teachers of polymer chemistry are teamed together, using one as principal teacher to teach in class of all the courses of polymer; experimental course can be placed differently at the pre-, mid- and post-stage of theoretical course, thus to meet the varying education goals for different students; compulsory content and extended content are arranged to help the top-level students to get improved education; for the assessment of polymer chemistry courses, a comprehensive balanced evaluation method is adopted by unifying theoretical course and experimental course. The teaching mode in this paper was found to resolve the problems of separate teaching and improve students' learning quality.

This article mainly introduces the online teaching practice of organic chemistry based on the Rain Classroom, WeChat-Enterprise and the supplement of the simultaneous MOOC course. It also illustrated the “questioning and probing” teaching system of “student as the center, teacher as the guide” with teaching examples. The online live teaching also integrates the interactive mode of bullet screen, WeChat group and group homework, focusing on the interaction between students and students, students and teachers, as well as students and teaching resources. Furthermore, the course paid more attention on the student's learning process by building a multi-dimensional assessment system to improve students' initiative and participation.

Taking the chapter of first law of thermodynamics in Physical Chemistry (I) as an example, this paper first discusses how to perfectly tune the teaching and studying status from offline to online by using “Rain Classroom” and “Tencent Online Education” as teaching platforms, then focuses on how teachers can guide students to accomplish the online studying task satisfactorily by making due efforts in adaption and change.

We described the application of balloons and balloon-ball-stick models in structure theoretical teaching. Balloons are excellent teaching tools in the learning of hybrid orbitals. Together with the ball-stick-models, they can help students understand conjugated molecules, comprehend conjugation and hyperconjugation effect, recognize molecular properties, grasp reaction mechanisms, and master molecular orbital theory. This experiential learning model is an excellent active learning method through involving students to operate the models by themselves. It not only greatly improves the students' interests in learning, but also increases their comprehending on the complicated and abstractive knowledge.

According to definition formula on titration error, the key to calculate titration error lies in volume ratio between titrant solution and analyte solution. In this paper, the general equation on volume ratio in complexometric titration was constructed and iteration strategy was proposed to solve the equation. The results of calculation examples showed the method is characterized of wide adaptability and high precision.

In this comprehensive experiment, potassium ferrioxalate was prepared by ferric chloride and potassium oxalate as raw materials and its structure was characterized. The composition and ion charge of the complexes was measured. The electronic spectra and infrared spectra of the ligands and complexes were mainly studied. The magnetic distance, XRD crystal structure, and thermal stability of the complex were measured. The experimental results show that the composition of the complex is K₃[Fe(C₂O₄)₃]·3H₂O with a yield of 90.0%. The value of the absorption peak of the electronic spectrum is in the range less than 350~400 nm, which is caused by the electronic transition from the ligand to the central ion. The infrared spectrum infers the presence of bidentate or chelated oxalate in the complex. The magnetic moment of the complex is 5.16 B.M.. The hybrid state of the central ion Fe³⁺ is sp³d². And the complex is a high-spin outer-orbital complex with an octahedral structure. Through this experiment, students can understand the principles of complex preparation, composition determination and structural characterization, and be familiar with various modern testing techniques. It can stimulate students' interests in scientific research, and cultivate students” comprehensive experimental and innovative abilities.

The discovery of crown ethers opened up a new discipline-supramolecular chemistry. The synthesis and characterization of this kind of substances were introduced into a comprehensive chemistry experiment in our college. A typical crown ether compound, named benzo-21-crown-7 (B21C7), was first synthesized by etherification reaction, and a complex (referred to as pseudorotaxane) was then formed by the host-guest interactions of B21C7 with secondary dialkylammonium salts. Moreover, its complexation ability between B21C7 and secondary dialkylammonium salts was investigated via nuclear magnetic resonance titration. The implementation of this experiment can not only improve the basic experimental operation ability of students, consolidate the understanding of professional knowledge, and train the ability of large-scale instrument test and analysis of students, but also widen the scientific research vision of students and improve their awareness of exploration and innovation. Thus, this experiment was suggested to set up to senior undergraduates and junior postgraduate.

The photocatalyst with high catalytic activity was prepared by hydrothermal treatment with bismuth nitrate and phosphomolybdic acid as raw materials. The photocatalyst was characterized by X-ray diffraction and scanning electron microscope. The surface photocatalytic degradation of tetracycline was studied with xenon lamp as light source. This experiment involves hydrothermal synthesis, structural characterization of inorganic nanomaterials and photocatalytic degradation of organic pollutants. It combines the theoretical content, experimental methods and scientific research frontier of inorganic chemistry, physical chemistry, organic chemistry and analytical chemistry, and it can comprehensively improve the comprehensive experimental skills and scientific research level of undergraduate students.

In the course design of chemical engineering principle, the scientific research project “dimethyl sulfide, methanol and water separation design project” entrusted by a pharmaceutical factory was transformed into a typical teaching case. Combined with modern computer-aided technology, the quantitative calculation software Gaussian and chemical simulation software Aspen Plus were introduced to carry out the design of the azeotrope separation by extractive distillation from the microscopic and macroscopic, respectively. Based on the density functional theory, it was confirmed that the existing component water could change the relative volatility of the binary azeotrope of dimethyl sulfide and methanol and eliminate the azeotrope via Gaussian software. Afterwards, the extractive distillation process for the azeotrope separation was further simulated and optimized using the Aspen Plus software. Finally, industrial design and equipment selection were carried out. The design of the above practical case creatively uses the existing components of the mixed liquid as the extractant, and realizes the separation of the azeotrope through the extractive distillation process, which makes up for the shortcomings of the product carrying trace third components in traditional extractive distillation. It greatly stimulates the students' interest in learning, enriches the teaching content of the course, and thoroughly explains the complex process of extractive distillation, which promotes the improvement of teaching quality and enhances the engineering design ability of students. The students participated in the National University Chemical Design Competition for many times and achieved excellent results.

In order to investigate the basic safety knowledge of chemical laboratory for first-year students, a questionair was conducted to explore the warning symbols, hazardous chemicals, waste and accident disposal among first-year undergraduates in the College of Chemistry and Chemical Engineering, Tianjin University of Technology. The results showed that 60.4% respondents confused the flammable pictogram with that of oxidizer, and the properties of hazardous chemicals and disposal of acid/base spill needed to be strengthened. Based on the results above, during the following safety education, the GHS pictogram and MSDS will be spreaded to the students to make up the deficiency specifically. And online resources will be also fully utilized to supplement the the deficiency in off-line safety education due to the limit of time and capacity.

Distribution of equilibrium concentration of solute between two immiscible phases is a core issue of liquid-liquid extraction. For most of theoretical and experimental courses in chemistry or chemical engineering, the extraction systems that showed the linear distribution were selected as teaching examples. However, the systems showing the non-linear distribution rarely occurred in teaching. This was because the current model applied in the systems mentioned above was quite complex. In the teaching research, we found that the common isotherm model can well describe the non-linear distribution of many systems, and that the distribution coefficient can be expressed by determined functional relationship as well. Further, we also found that the model applicability of extraction systems highly related to interaction mechanism among solute, solvent and extractant thereof. Above all, applying the isotherm model in the liquid-liquid extraction can solve the complexity issue of the current model, expand the teaching contents, help students better understand the extraction mechanism, and train them in scientific thinking.

Through the literature review of all the articles on the topic of critical thinking (CT)published in the Journal of Chemical Education from 1987 to 2019, the literatures can be divided into five categories based on the content analysis results. The most representative literature is selected from each category as an example to provide a path for the development of critical thinking skills from the five dimensions of experimental process analysis, active learning teaching methods, curriculum planning, correcting textbook errors and analyzing network information. Finally, this paper summarizes the current research status and trends of critical thinking in international chemistry education.

Through the design and implementation of teaching experiments at a liberal arts college in the United States, this article explores the role of Toulmin's Argumentation Pattern (TAP) from a brand-new angle in helping students construct scientific explanations with their reasonings, as well as in improving students' understanding of concepts, so as to provide a useful reference for the reform of teaching methods in applied undergraduate colleges in China.

It has been a century since polymer science was established by H. Staudinger in 1920. Based on the previous Nobel prizes in polymer science and related fields, this paper reviews the establishment of the concept of polymer, polymer synthetic chemistry, polymer theory, functional polymer and other development milestones in polymer science, and analyzes the future development trends of polymer discipline.