Organic molecules have become one novel type of catalysts developed after enzymes and metal catalysts, which are named as organocalysis, the third type of catalysis. As a new tool toward the precise construction of molecules, organocatalysis has a huge impact on the development of chiral new drugs, which has been used in the fields of pharmacy, pesticides, chemicals, materials, and so on. The 2021 Nobel Prize in Chemistry was awarded to German chemist Benjamin List and American chemist David W. C. MacMillan for their pioneering and important contributions to this field. This article will briefly describe chirality and asymmetric catalysis, especially, the history of organocatalysis development, its advantages and future prospects.
In the past two decades, fundamental chemistry laboratory teaching courses in Chinese universities and colleges have experienced series of alterations and reform, not only in philosophies, contents, and teaching standards, but also in organizations and evaluations. Facing the new historical opportunities and times, it's necessary for us to deeply understand and clarify the nature and role of basic chemistry laboratory teaching during the stage of undergraduates. We neither can look down on their course positions in the teaching program, nor can overstate their roles in the training program. The real effects of basic laboratory teaching must be revealed as it should be, which have play an irreplaceable role in transmission of the Third Kind of Knowledge as well as in cultivating the metacognition. Only in this way can we be far away from negligence and confusion during the teaching reformation tides.
Under the influence of COVID-19, online learning has been widely popularized and promoted. With the fading of the outbreak, online learning is not widely used, though it is still used as one of the teaching and learning approaches. According to the questionnaire survey on the online learning situation of Hubei Normal University and Hanjiang Normal College, it is found that students are much less satisfied with online learning than offline learning, and the result of online learning is not as good as offline learning. How to make students accept online learning and make it widely used in universities, this research suggests a few strategies.
Chemical experiment courses are important basic curriculum offered by the universities and colleges involving science and technology, and they are also indispensable links for learning and understanding chemistry. Fully extracting ideological and political elements relevant to the chemical experimental courses and integrating them into course teachings can not only help undergraduates deeply understand the theoretical knowledge and activate the classroom atmosphere, but also stimulate their learning enthusiasm and cultivate their professional quality and social responsibility, achieving the goal of knowledge education and value guidance in higher education.
Organic chemistry is a basic course for many students majoring in science, technology, agriculture, medicine. There are many knowledge points and some of them are quite difficult to understand, therefore, Q & A are always highly desirable. Today, with the development of the internet environment, the use of the internet platform to help answering questions can be an important means of auxiliary teaching. After groping and trying, the organic question and answer group of the study guidance center of the Chemistry Department of Zhejiang University has successfully built a public question answering platform for organic chemistry teaching, which has been in operation over 1 year. It has received the active participation of students from various colleges and departments and the full support of teachers and students of the chemistry department, and the evaluation is good. This paper will introduce the method, effect and improvement direction of realizing public question answering platform by using student volunteer organization and QQ group construction.
Currently, there is a large gap between the classical courses of graduate and lab research activities, which gives graduates/supervisors an incorrect impression that classical course learning does not benefit their lab works too much. To bridge this gap and revise this underestimation on the values of classical courses, we proposed to train researching abilities during the teaching of classical courses through a variety of precisely designed immersion and interactive teaching/learning approaches such as group discussions, introduction of latest developments and applications of classical theories, understanding of paradigm in science developments, etc. We implemented the measurements in the colloids and Interface chemistry course and received excellent feedbacks from graduates as well as course-supervising groups of the university.
This paper expounds the significance of carrying out the ideological and political education in the course of basic medical chemistry experiment. The ideological and political elements in this course was excavated according to its characteristics. The syllabus revision, case design, formative evaluation, construction of online experimental teaching platform and teachers' morality construction were performed to cultivate students' rigorous scientific spirit, seeking truth attitude, good experimental habits, sincere and cooperative team spirit and conscious awareness of environmental protection. The path of ideological and political education in the experimental teaching of basic medical chemistry was explored. A relatively complete teaching system was established to carry out ideological and political education in the whole process and all-round way in the non-professional ideological and political courses. The core value education of Chinese socialism was carried out throughout the curriculum. The moral value establishment and people cultivation was conducted in unconscious way. The system has reference value for other non-professional ideological and political courses to carry out ideological and political education.
Laboratory teaching plays an irreplaceable role in cultivating the practical ability and scientific literacy of engineering students. Experimental preview is very important for students to form good laboratory habits and safety awareness. Based on the platform of "Wechat + Questionnaire star", this paper reformed the preview mode of university chemistry laboratory, introduced the concept of game breakthrough, and developed the online examination small program of breakthrough type preview of university chemistry laboratory, to replace the traditional paper preview thinking questions, and guide students to actively accept the challenge of breakthrough type. The practice achieved good teaching effect.
Facing the emerging frontier areas and policy orientation for national and local economic construction needs, we summarized some experience of curriculum form and content in our innovation seminars in combination of present situation of teaching basic knowledge of chemistry.
In response to the teaching needs of the post-epidemic era and the insufficiency of information teaching resources in local universities, a new model of WeChat integrating inorganic chemistry laboratory teaching was initially explored, through the creation of WeChat official account and WeChat group. Before class, students will be guided to preview the tweet on the official account, and the test will be conducted through the WeChat group. Adjustment is made based on the test feedback to the key points of the experiment that needs to be discussed. These photos and videos of experimental procedure, experimental phenomena and the experimental results will be shared through the WeChat group by the teacher and students during the experiment process, and that fully stimulates students' interest in doing experiments and enhance their abilities. After class, combined with photos of wrong operations, tweets of experimental feedback are sent to help students form a habit of reflection.
As a star in the field of materials science, the development of covalent organic frameworks (COFs) is based on the successful selection of organic reactions and the optimization of synthetic conditions. This paper discusses the way of introducing the bonding manner of COFs into the organic chemistry teaching, demonstrating the application of organic reactions in the design of new nanomaterials. The teaching mode of integration of scientific research and teaching can cultivate students' ability to acquire knowledge and use knowledge to solve complex problems; Meanwhile, it can mobilize students' learning interest, expand their scientific research horizon and stimulate their enthusiasm for scientific research. It can enhance students' sense of major identity and cultivate students' sense of innovation and social responsibility from scientific research achievements. The fusion of scientific research and teaching is an important link in the cultivation of innovative students.
Laboratory teaching involves teaching, management, service and environment education. A good laboratory environment can not only play a subtle role in students, but also promote the development and implementation of teaching, management and service education. This article mainly introduces the practice and experience of strengthening the connotation construction of laboratory teaching environment and improving the quality of laboratory environment education of the "student-centered" at National Experimental Teaching Demonstration Center of Chemistry, Xiamen University, in order to provide a replicable and popularized construction scheme for laboratory teaching "ideological politics".
Changing teaching philosophy is an important means to improve teaching level and a powerful way to promote teaching reform. This curriculum reform integrates the educational concept of ecological civilization into the course of electrochemistry and life. Combined with the publicity of garbage classification in communities and schools in recent years, the knowledge points of garbage classification are organically embedded into the curriculum teaching. The teaching mode is guided by teachers, explored by students themselves, discussed in groups after class, summarized and reported. And then a curriculum structure design is formed with ecological civilization education idea as the core idea, electrochemical curriculum knowledge content as the central axis, and garbage classification knowledge point as the "wings". The importance of ecological civilization, the change of teaching philosophy, curriculum examples, assessment and evaluation are discussed.
The integration of professional courses and ideological and political education is the fundamental task of moral education in colleges and universities. In this study, based on the character and teaching objectives of structural chemistry, possible methods for ideological and political education in the course are explored for cultivating students' philosophy and science, national pride and self-confidence in order to realize the organic unity of knowledge imparting and value leading.
Aiming at the problems of the traditional BOPPPS model, such as insufficient understanding of student conditions, poor fault tolerance, delayed checking of learning effects, and loose connection between teaching contents, this article proposes the teaching design method based on Rain Classroom and BOPPPS improved model based on the student-centered teaching concept by focusing on student analysis. This paper also expounds the design concept, discusses the design link of the improved model, and introduces the teaching reform and practice by taking the course of "College Chemistry" as an example.
Knowledge visualization is an effective technology to promote knowledge learning, collation, creation and dissemination. By constructing teaching design based on self-generated drawing strategy and graphic organizer strategy in inorganic chemistry teaching, the teaching content and teaching method are highly integrated with visual representation, which can effectively impart explicit knowledge, cultivate students' thinking ability and realize the integration of ideological and political education. The results confirm that knowledge visualization can promote students to actively participate in the teaching process, arouse students' positive thinking and lays a good foundation for the cultivation of students' innovative ability and creative thinking.
Bread is the staff of life. However, few topics have been addressed on the chemical reactions related to food systematically and professionally in Chinese literatures. Such situation undoubtedly prevents the public to understand the essence of food through the phenomena, and results in the detachment of chemistry courses with livelihood. Based on this background, this manuscript focuses on the introduction of non-enzymatic Browning reactions, mainly caramel reaction, Maillard reaction and vitamin C oxidation, which contribute to the unique flavor and color of food. The molecular transformation in food related to medicine is also discussed from the perspective of chemistry, such as the conversion of iodine in table salt within the body, health adverse effects of trans-fatty acid, and the alcohol metabolism. It is hoped to set up a close connection between chemistry teaching and real life in order to bridge the gap between food science, medicine and other fields.
Acetal/ketal is a kind of important organic compounds, which is prepared by the nucleophilic addition reaction of aldehyde/ketone with alcohol or orthoformate. This reaction is also widely applied for protection of carbonyl group of aldehyde/ketone or ethylene glycol in organic synthesis. Therefore, synthesis of acetal/ketal attracts extensive concern. According to the different reaction systems, the research progress of acetal/ketal synthesis in recent years was reviewed in detail from three aspects, including acid catalysis, electrocatalysis and photocatalysis. It is expected that students could master this basic reactions and students' innovation ability will be developed by this review.
The content of the Nobel Prize in Chemistry has witnessed the development of chemistry, the inextricable connection between chemistry and human life, and the forefront of the development of chemistry. With the Nobel Prize in Chemistry as the main line, we use the interesting facts of the Nobel Prize in Chemistry to explain that the discipline of chemistry will be the basis of human survival and development, even an important contribution to human society, survival and development. We hope to make everyone realize the importance of chemistry and better understand how to carry out chemistry research, and to promote the rapid development of chemistry.
The 2021 Wolf Prize in Chemistry was awarded to Profs Leslie Leiserowitz and Meir Lahav for demonstrating the interaction between three-dimensional molecular structure and the structure of organic crystals. Their findings greatly complement the scientific understanding of the mechanisms and mechanisms of self-assembly of organic macromolecules. It has made outstanding contributions to the development of organic crystal chemistry. This article took this opportunity to briefly introduce the two winners of the Wolf Prize in Chemistry in 2021 and the history and status of the Wolf Prize.
In the Co2+ identification experiment, it was accidentally found that with an appropriate amount of SCN- added into CoCl2 solution, the solution presented reversible thermochromic phenomenon. Inspired by this phenomenon, the "flipped classroom" mode of experimental teaching of "doing first, teaching later, teaching determined by doing" was adopted accordingly based on the analysis and discussion of its thermochromic mechanism. Specifically, students do the experiment first and have questions during the experimental process, then the teacher demonstrates with students based on their questions, leading students to intuitive understanding of the thermochromic phenomenon and its influencing factors of some Co(Ⅱ) compounds or complexes. This article inspires students to use chemical principles and knowledge to explain and discuss the nature of thermochromic phenomenon, so as to deepen students' understanding of the structure, properties and concept of splitting energy of complexes. It also cultivates the students' ability of observation, analysis, judgment, induction, reasoning, summary, conclusion regular and "critical" thinking.
The fundamental chemistry laboratory mainly offers basic or large-scale general education courses, which are mainly aimed at non-chemistry majors or undergraduate students. In practice, the teaching process of fundamental chemistry laboratory often involves dangerous chemical reagents or high temperature, high pressure and other dangerous operations. Under the new situation that the enrollment of students is expanding, and the teaching tasks of basic courses also grow with each passing day. The safe operation and management of fundamental chemistry laboratory are crucial. Taking the fundamental chemistry laboratory of Xi'an Jiaotong University as an example, the current situation, the problems and the solutions of the fundamental chemistry laboratory in our school are introduced. All these means could provide reference for the safe operation and management of the similar chemical laboratories.
A new experiment of the photoluminescence spectrum of organic molecules was introduced to undergraduate teaching. The emission behaviors of different aggregation with perylene and 1, 1, 2, 3, 4, 5-hexaphenylsilole (HPS) as typical luminophores were measured so as to observe the different phenomena of aggregation-caused quenching (ACQ) and aggregation-induced emission (AIE). The crystal structures characteristics of the above molecules could be obtained by the use of the Cambridge Crystallographic Data Centre (CCDC). The causes of the phenomena of AIE and ACQ were analyzed from the aspects of structures of molecular crystals. Therefore, the intrinsic relations between photoluminescence mechanism and molecular states were discussed on this basis. In this paper, the design, contents and conclusions of the photoluminescence experiment were elaborated in detail. Combining with the teaching process, the teaching effects were discussed for broadening the undergraduates' horizons as well as improving their cognitive abilities and scientific research qualities.
This study illustrates an exploratory comprehensive experiment covering organic, medicinal chemistry and instrumental analysis. In this experiment, (Z)-enaminones with a 3, 4-dihydroquinoxalin-2(1H)-one with anticancer, antibacterial, antidiabetic and antiviral activities was selected as the synthesis and research object. The first use of a recyclable acid resin (Amberlyst 15) as heterogeneous catalyst, under the coordination of visible light catalysis, one step synthesis anticancer quinoxalinone JNK3 inhibitors. Based on validated studies in the hot frontier, this experiment helps students to learn the experimental method of classical Mannich reaction, and strengthen the understanding of professional knowledge; it also helps students to study heterogeneous catalytic and optical knowledge based on the most recent advance; students' exploration innovation consciousness is improved by combining with the expanded reading. It is suggested that the course of "Comprehensive Chemistry Laboratory" should be included in senior undergraduate and junior graduate students.
A new comprehensive university chemistry experiment, "Synthesis, structure characterization, and room temperature phosphorescence property of 9-(4-Bromobutyl)-9H-carbazole prepared by phase transfer catalysis method", was recommended for undergraduates. 9-(4-Bromobutyl)-9H-carbazole was synthesized by phase transfer catalysis reactions, and the structure and purity of 9-(4-Bromobutyl)-9H-carbazole were confirmed by nuclear magnetic resonance (1H NMR), high resolution mass spectrometer (HRMS), as well as fourier transform infrared spectroscopy (FTIR). The room temperature phosphorescence property of the 9-(4-Bromobutyl)-9H-carbazole was studied with UV-Vis absorption, steady and transient state fluorescence spectroscopy, and density functional theory (DFT) calculations. This comprehensive chemistry experiment included the knowledge of organic chemistry, physical chemistry, analytical chemistry, instrumental analysis and theoretical chemistry. Thus, the comprehensive chemistry experiment should be arranged for junior university students.
In this paper, the physical and chemical properties of micelle formation process of surfactants were studied by studying the influence of temperature and salt concentration on the critical micelle concentration (CMC) of sodium dodecyl sulfate (SDS) using conductivity method. The thermodynamic parameters of micelle formation were obtained according to the pseudo-phase separation model, and the conductance activation energy of the system dependence of temperature and SDS concentration was discussed. The results showed that CMC of SDS was increased with the increasing of temperature, and decreased with the increasing of sodium chloride concentration, suggesting a spontaneous, exothermic and entropy-increasing process in the micelle formation of SDS in aqueous solution; in kinetics, the relationship between the conductivity of the SDS solution and the temperature conforms to the Arrhenius formula, the activation energy information can reveal the mechanism of ionic surfactants forming micelles.
Phthalocyanine blue B was produced by ammonolysis reaction, substitution reaction, complexation reaction and condensation reaction using phthalic anhydride, urea and cuprous chloride as raw materials. The morphology of the intermediate and the product were observed by metallurgical microscope, and the structure of the functional group and the characteristic peaks of analytical spectrum were characterized by IR and UV-visible spectroscopy, and the optical stability of the product was investigated. Through this experiment, different chemical unit operations are brought together into a knowledge chain, and different types of reactions ware integrated to achieve the goal of inspiring innovation consciousness, improving comprehensive knowledge and practical skills.
In the inorganic chemistry experiment, "Preparation and Component Determination of Hexamine Cobalt Chloride (Ⅲ)", the yield of product is low, which impedes the implement of subsequent experiment and teaching. Based on basic principles of chemistry, the effects of the quantity and particle size of activated carbon catalyst and the amount of hydrochloric acid and water were investigated. The experimental results showed that with 0.2 g, 120 mesh activated carbon catalyst, acid solution of 1 mL HCl plus 25 mL hot H2O, and 3 mL concentrated hydrochloric acid, the yield of hexamine cobalt chloride(Ⅲ) was up to 42.5%, the color(orange), purity and crystallinity of the product were significantly improved. Through the experiment, the ability of students to apply the basic principles of chemistry to solve problems was enhanced.
In Chinese literature on polymer chemistry and photo-chemistry, "quench" and "quencher" are both expressed in two different terms. And this has been bringing trouble to teaching and academic exchanges. To solve this problem, an analysis and textual research were made on these words from both linguistics and chemistry perspectives. A solid conclusion is led, and the right word for quench and quencher in Chinese are given. Also, a suggestion is made that, it should be adopted in the relevant books and specifications.
In this paper, the physical meaning of C in BET equation is introduced from the view of kinetics and statistical thermodynamics. The influence of the size of C on the shape of adsorption isotherm is analyzed. The relationship between the inflection point, the position of B point and the size of C on the adsorption isotherm is deduced, and the relationship between C and relative pressure, the fraction of covered surface when the adsorption capacity reaches one-way, is also deduced. This paper introduces the method to ensure the positive value of C by mathematical method, explains a common phenomenon in data analysis, and discusses the lower limit of C from the mathematical form and physical meaning of BET equation.
Hückel Molecular Orbital (HMO) theory is popular in chemistry, but it assumes that the reduced resonance integrals exist only between the nearest-neighbor carbon atoms. Such an approximation has been justified by the explicit inclusion of the resonance integrals between the meta-directing π-bonded atoms. The energy eigenvalues are obtained using the symmetry-adapted molecular orbitals, together with the extra stabilization energy due to symmetry breaking. The polyynic geometries of cyclo[2n]carbons with alternating angles are explained rationally using the modified HMO model, which gains new insights on the second-order Jahn-Teller effect for carbon rings.
Free energy of a single polymer chain in polymer solutions is critical for the derivation and understanding of the scaling law between the polymer size and its degree of polymerization. This work provides a novel derivation of the single-chain free energy based on the Flory lattice model.
In the long history of human beings, for every leap and progress, there is a strong hand of destiny behind-heat, which constantly guiding the path of civilization and inspiring the understanding of thermal science and technology. The thermal technologies of ancient China was in the leading position in the world for a long time. The Chinese people's exploration of heat has created great achievements and made essential contributions to the human civilization, which is really worthy of our pride. However, due to the closeness of feudal society and the conservatism of people's way of thinking, the rejection of the impact of foreign science and culture, and the unscientific research methods, China's thermal technology and science began to lag behind the West in modern times, which is a very regrettable thing. This paper briefly reviews the history of Chinese civilization's constant exploration and confrontation with heat in the history.
This paper presents a comprehensive overview on the discovery and development of optical activity and chiroptical spectroscopy since the nineteenth century, with emphasis on the background and basic principles of the development of optical rotatory dispersion (ORD), electron circular dichroism (ECD) and vibrational circular dichroism (VCD) spectroscopy. Therein, the outstanding contributions of Chinese scientists Guangxian Xu and Yunjie Xu in the development of chiroptical spectroscopy are specifically mentioned.
Can we count hydrocarbon isomers systematically and accurately? This article demonstrates a neat solution by introducing generating functions and Pólya's Counting Theorem based on high-school-level mathematics and chemistry knowledge. Starting with alkyls, we derive formulae to enumerate acyclic isomers (stereoisomerism not considered) of alkanes, monoalkenes, monoalkynes, benzene derivatives, disubstituted alkanes and dienes. We then check our results against manual enumeration to show their correctness. We also explore the asymptotic behavior of isomerism and empirically propose approximation formulae for counting isomers of the aforementioned hydrocarbons. Compared to results from literature, we strive to reduce advanced mathematical concepts involved to eliminate barriers for inquisitive high school readers, who may gain a more in-depth understanding of hydrocarbon structure and train their computational thinking. Compared to results from Chinese literature, our derivation is more concise, flexible and extendable.