Login In
2023 Volume 38 Issue 1
2023, 38(1): 1-7
doi: 10.3866/PKU.DXHX202212058
Abstract:
The 2022 Nobel Prize in Chemistry was awarded to Carolyn R. Bertozzi, Morten Meldal, and K. Barry Sharpless, for the development of click chemistry and bioorthogonal chemistry. Stemming from the advances on the methodology of organic synthesis, click chemistry provides a versatile tool for coupling molecules with high efficiency under mild conditions. Orignially developed for specific labeling and visualization of glycans–an important biomacromolecule in living systems–bioorthogonal chemistry is a class of ligation reactions which neither interfere with nor being interfered by the surrounding biological milieu. Click chemistry and bioorthogonal chemistry are interconnected through similar philosophy and have emerged as the most useful chemical reactions in chemistry, biomedicine, and material science. Here, we briefly introduce the fundamental concepts and frontiers related to click chemistry and bioorthogonal chemistry.
The 2022 Nobel Prize in Chemistry was awarded to Carolyn R. Bertozzi, Morten Meldal, and K. Barry Sharpless, for the development of click chemistry and bioorthogonal chemistry. Stemming from the advances on the methodology of organic synthesis, click chemistry provides a versatile tool for coupling molecules with high efficiency under mild conditions. Orignially developed for specific labeling and visualization of glycans–an important biomacromolecule in living systems–bioorthogonal chemistry is a class of ligation reactions which neither interfere with nor being interfered by the surrounding biological milieu. Click chemistry and bioorthogonal chemistry are interconnected through similar philosophy and have emerged as the most useful chemical reactions in chemistry, biomedicine, and material science. Here, we briefly introduce the fundamental concepts and frontiers related to click chemistry and bioorthogonal chemistry.
2023, 38(1): 8-21
doi: 10.3866/PKU.DXHX202209017
Abstract:
The important role of analytical chemistry teaching in professional training of undergraduate students in chemistry majors is discussed. The significance, necessity, documental basis for establishing this detailed suggestion for teaching contents and teaching requirements, and the principles for using this suggestion are explained. This suggestion is set with clear statements of the requirements of knowledge, abilities and quality of analytical chemistry teaching. This suggestion can provide guidance on the teaching reform and innovation, the construction of teaching resources, the compilation of textbooks and the assessment of teaching effectiveness for analytical chemistry course at present and in future.
The important role of analytical chemistry teaching in professional training of undergraduate students in chemistry majors is discussed. The significance, necessity, documental basis for establishing this detailed suggestion for teaching contents and teaching requirements, and the principles for using this suggestion are explained. This suggestion is set with clear statements of the requirements of knowledge, abilities and quality of analytical chemistry teaching. This suggestion can provide guidance on the teaching reform and innovation, the construction of teaching resources, the compilation of textbooks and the assessment of teaching effectiveness for analytical chemistry course at present and in future.
2023, 38(1): 22-28
doi: 10.3866/PKU.DXHX202202010
Abstract:
A new teaching methodology was explored to synergistically combine theoretical and experimental courses in physical chemistry. Experimental principles were introduced in the theoretical course by selecting a suitable point of introduction. Students’ understanding of the subject was enhanced, and so was their interest in learning and acquiring more knowledge. The class atmosphere was active; the students were better integrated into the classroom environment and interacted better with each other. Teachers should guide students on learning the thought process and methods of designing experiments, and stipulate specific requirements on data recording and processing during experimental courses. The experimental reports of the students were more logical than before. They were able to correctly analyze experimental errors, and could propose suggestions on the experimental approach, experimental method, and instrumentation. Thus, this methodology can foster logical thinking capabilities and nurture the practical abilities of students. The implementation of this teaching methodology requires strong enforcement by the school and the department.
A new teaching methodology was explored to synergistically combine theoretical and experimental courses in physical chemistry. Experimental principles were introduced in the theoretical course by selecting a suitable point of introduction. Students’ understanding of the subject was enhanced, and so was their interest in learning and acquiring more knowledge. The class atmosphere was active; the students were better integrated into the classroom environment and interacted better with each other. Teachers should guide students on learning the thought process and methods of designing experiments, and stipulate specific requirements on data recording and processing during experimental courses. The experimental reports of the students were more logical than before. They were able to correctly analyze experimental errors, and could propose suggestions on the experimental approach, experimental method, and instrumentation. Thus, this methodology can foster logical thinking capabilities and nurture the practical abilities of students. The implementation of this teaching methodology requires strong enforcement by the school and the department.
2023, 38(1): 29-33
doi: 10.3866/PKU.DXHX202202020
Abstract:
To improve the quality of professional training in vocational colleges for medicine and health, we explore teaching reforms for analytical chemistry courses considering a diverse student background. By focusing on teaching materials and methods, such as theoretical teaching resources, practical training platforms, curriculum ideological and political education, and teachers’ teaching abilities, we have deeply integrated information technology to promote the independent, ubiquitous, and personalized learning of students opting for higher vocational education. Thus, we have initiated a cycle of student improvement and teacher achievement, and improved the teaching efficacy of analytical chemistry courses in medicine and health colleges. Our work serves as a reference for driving teaching reforms in theoretical foundation courses considering a diverse student background.
To improve the quality of professional training in vocational colleges for medicine and health, we explore teaching reforms for analytical chemistry courses considering a diverse student background. By focusing on teaching materials and methods, such as theoretical teaching resources, practical training platforms, curriculum ideological and political education, and teachers’ teaching abilities, we have deeply integrated information technology to promote the independent, ubiquitous, and personalized learning of students opting for higher vocational education. Thus, we have initiated a cycle of student improvement and teacher achievement, and improved the teaching efficacy of analytical chemistry courses in medicine and health colleges. Our work serves as a reference for driving teaching reforms in theoretical foundation courses considering a diverse student background.
2023, 38(1): 34-40
doi: 10.3866/PKU.DXHX202203073
Abstract:
To save the problems in physical chemistry laboratory teaching, a student-centered teaching implementation program based on OBE (Outcomes-based education) theory is proposed from the aspects of formulating course objective, constructing application-oriented courses, developing course resources, and restructuring assessment system. Combined with actual cases, the OBE teaching mode is applied to pre-course guidance, in-class exercises and post-course intensive training. This teaching mode has exerted the subjective initiative of students, enhanced students’ comprehensive innovation ability, and improved teaching effects to a great extent.
To save the problems in physical chemistry laboratory teaching, a student-centered teaching implementation program based on OBE (Outcomes-based education) theory is proposed from the aspects of formulating course objective, constructing application-oriented courses, developing course resources, and restructuring assessment system. Combined with actual cases, the OBE teaching mode is applied to pre-course guidance, in-class exercises and post-course intensive training. This teaching mode has exerted the subjective initiative of students, enhanced students’ comprehensive innovation ability, and improved teaching effects to a great extent.
2023, 38(1): 41-47
doi: 10.3866/PKU.DXHX202203062
Abstract:
While taking fundamental chemistry experiments courses, students may easily lose their interest owing to their limited understanding of related chemical principles. Many of these principles involve microscopic concepts and quantities hard to determine and describe, such as the interaction among matters, state of electrons in matters, the interactions between light and electricity with molecules. Results from theoretical chemistry investigations are capable to bridge this gap and present these quantities and concepts more vivid for students to understand the principles easily. Considering the separation of alcohols by gas chromatography as an example, we attempted to combine theoretical chemistry investigations with fundamental chemistry experiments to help students rationalize the chromatography theory with experimental and theoretical results. In addition to conventional experiments, students investigated the alcohols- adsorbents interactions theoretically and analyzed the results. This approach not only successfully stimulated students to learn and understand chemical principles more comprehensively, cultivated their problem identification and resolution abilities, but also promoted the teaching quality, thus benefiting the cultivation of top innovative talents in chemistry.
While taking fundamental chemistry experiments courses, students may easily lose their interest owing to their limited understanding of related chemical principles. Many of these principles involve microscopic concepts and quantities hard to determine and describe, such as the interaction among matters, state of electrons in matters, the interactions between light and electricity with molecules. Results from theoretical chemistry investigations are capable to bridge this gap and present these quantities and concepts more vivid for students to understand the principles easily. Considering the separation of alcohols by gas chromatography as an example, we attempted to combine theoretical chemistry investigations with fundamental chemistry experiments to help students rationalize the chromatography theory with experimental and theoretical results. In addition to conventional experiments, students investigated the alcohols- adsorbents interactions theoretically and analyzed the results. This approach not only successfully stimulated students to learn and understand chemical principles more comprehensively, cultivated their problem identification and resolution abilities, but also promoted the teaching quality, thus benefiting the cultivation of top innovative talents in chemistry.
2023, 38(1): 48-55
doi: 10.3866/PKU.DXHX202201044
Abstract:
Based on an investigation of extracurricular reading among undergraduate chemistry students at six universities in Hunan Province in 2003 and 2013, we conducted another investigation and comparative analysis of extracurricular reading in 2021. We found some problems among the current regular chemistry students, such as a low extracurricular reading volume, neglect of periodical reading, neglect of library borrowing, and other similar problems. According to this, some suggestions are put forward to encourage extracurricular reading among regular chemistry students, such as strengthening the educational guidance of first-year students, increasing the attendance of classroom teaching sessions, developing optimal habits through extracurricular innovation, and promoting reading through community activities.
Based on an investigation of extracurricular reading among undergraduate chemistry students at six universities in Hunan Province in 2003 and 2013, we conducted another investigation and comparative analysis of extracurricular reading in 2021. We found some problems among the current regular chemistry students, such as a low extracurricular reading volume, neglect of periodical reading, neglect of library borrowing, and other similar problems. According to this, some suggestions are put forward to encourage extracurricular reading among regular chemistry students, such as strengthening the educational guidance of first-year students, increasing the attendance of classroom teaching sessions, developing optimal habits through extracurricular innovation, and promoting reading through community activities.
2023, 38(1): 56-64
doi: 10.3866/PKU.DXHX202203005
Abstract:
On the basis of blended teaching reform, flipped classroom was applied to the teaching of physical chemistry experiment. The teaching process included online learning before class, classroom demonstration, discussion and laboratory work, and consolidation and improvement after class. The validity of this teaching mode was verified by quantitative research and questionnaire survey. The results showed that this teaching mode can improve students’ academic performance, develop their initiative, stimulate their learning enthusiasm, and improve classroom participation.
On the basis of blended teaching reform, flipped classroom was applied to the teaching of physical chemistry experiment. The teaching process included online learning before class, classroom demonstration, discussion and laboratory work, and consolidation and improvement after class. The validity of this teaching mode was verified by quantitative research and questionnaire survey. The results showed that this teaching mode can improve students’ academic performance, develop their initiative, stimulate their learning enthusiasm, and improve classroom participation.
2023, 38(1): 65-70
doi: 10.3866/PKU.DXHX202205040
Abstract:
Based on the outcome-based education (OBE) and by combining with the instructional objectives of Organic Chemistry in USTC and Learning Pyramid, we have designed an online and offline blended “PTDCA” teaching method of guided preview (P), precise teaching (T), mutual discussion (D), demonstrative comments (C) and whole process assessment (A). This teaching method is student-centered and achievement-oriented, and could guide students to improve their learning initiative and ability to solve practical problems. The method has been applied to practical teaching, achieved good teaching results and achieved the expected goal.
Based on the outcome-based education (OBE) and by combining with the instructional objectives of Organic Chemistry in USTC and Learning Pyramid, we have designed an online and offline blended “PTDCA” teaching method of guided preview (P), precise teaching (T), mutual discussion (D), demonstrative comments (C) and whole process assessment (A). This teaching method is student-centered and achievement-oriented, and could guide students to improve their learning initiative and ability to solve practical problems. The method has been applied to practical teaching, achieved good teaching results and achieved the expected goal.
2023, 38(1): 71-75
doi: 10.3866/PKU.DXHX202203042
Abstract:
The policy of public funded normal students is of great significance to promote the effective allocation of teachers and promote the balanced development of compulsory education. Compared with the public funded normal students in the subordinate normal universities, the training of public funded normal students in the provincial normal universities has a certain gap in both the objective conditions of running a school and the level of students’ subjective ability. The chemistry major of Sichuan Normal University adopts the strategy of “two layers and three steps” to carry out layered training for public funded normal students and teach students according to their aptitude. After testing the students’ learning situation, the students are graded. The excellent students mainly carry out research-based learning and innovative experimental learning, and the ordinary students carry out intensive training of weak knowledge and basic experimental skills; Establish a quality evaluation system and implement the dynamic adjustment of students’ level after a period of time, so as to stimulate students’ internal potential. This strategy has effectively improved the learning motivation and teaching ability of public funded normal students.
The policy of public funded normal students is of great significance to promote the effective allocation of teachers and promote the balanced development of compulsory education. Compared with the public funded normal students in the subordinate normal universities, the training of public funded normal students in the provincial normal universities has a certain gap in both the objective conditions of running a school and the level of students’ subjective ability. The chemistry major of Sichuan Normal University adopts the strategy of “two layers and three steps” to carry out layered training for public funded normal students and teach students according to their aptitude. After testing the students’ learning situation, the students are graded. The excellent students mainly carry out research-based learning and innovative experimental learning, and the ordinary students carry out intensive training of weak knowledge and basic experimental skills; Establish a quality evaluation system and implement the dynamic adjustment of students’ level after a period of time, so as to stimulate students’ internal potential. This strategy has effectively improved the learning motivation and teaching ability of public funded normal students.
2023, 38(1): 76-87
doi: 10.3866/PKU.DXHX202203061
Abstract:
This study briefly introduces the implementation scheme and curriculum objectives for constructing the ideological and political education system of inorganic chemistry based on outcome-based education (OBE) theory. It introduces the construction of the ideological and political material database for the course in terms of traditional culture and patriotism, scientific spirit and methods, principles of Marxist philosophy, and the concept of sustainable development. Subsequently, it focuses on the methods of designing classroom teaching and demonstrates the practice of organically integrating knowledge transfer, ability improvement, and valuable guidance throughout the teaching process. Through discussions and writing course papers, students are encouraged to debate, reflect, and experience. This approach enables the students to understand and recognize the value of the course objectives and adopt them into their own value consciousness and practical actions to achieve the maximum learning results and effectively realize the ideological and political objectives of the course.
This study briefly introduces the implementation scheme and curriculum objectives for constructing the ideological and political education system of inorganic chemistry based on outcome-based education (OBE) theory. It introduces the construction of the ideological and political material database for the course in terms of traditional culture and patriotism, scientific spirit and methods, principles of Marxist philosophy, and the concept of sustainable development. Subsequently, it focuses on the methods of designing classroom teaching and demonstrates the practice of organically integrating knowledge transfer, ability improvement, and valuable guidance throughout the teaching process. Through discussions and writing course papers, students are encouraged to debate, reflect, and experience. This approach enables the students to understand and recognize the value of the course objectives and adopt them into their own value consciousness and practical actions to achieve the maximum learning results and effectively realize the ideological and political objectives of the course.
2023, 38(1): 88-96
doi: 10.3866/PKU.DXHX202201037
Abstract:
Two-photon absorption (2PA) and two-photon excited fluorescence (2PEF) have received extensive attention due to their potential applications in the fields of high-resolution bioimaging, photodynamic therapy, optical power limiting, three-dimensional microfabrication and high-capacity data storage, etc. Innovative preparation of novel 2PA materials involves nonlinear optical characterization, photophysical studies and the underlying structure-property relationships. 2PA and 2PEF feature the characteristics of interdisciplinary and cross-fields. Aiming to prompt the development of 2PA mechanics and guide for designing efficient 2PA materials, we identify several key questions related to the photophysical processes and characterization methods of 2PA. The effect of laser characteristics on the nonlinear results is illustrated based on our research contributions and the future perspective and challenges in this field are also pointed out.
Two-photon absorption (2PA) and two-photon excited fluorescence (2PEF) have received extensive attention due to their potential applications in the fields of high-resolution bioimaging, photodynamic therapy, optical power limiting, three-dimensional microfabrication and high-capacity data storage, etc. Innovative preparation of novel 2PA materials involves nonlinear optical characterization, photophysical studies and the underlying structure-property relationships. 2PA and 2PEF feature the characteristics of interdisciplinary and cross-fields. Aiming to prompt the development of 2PA mechanics and guide for designing efficient 2PA materials, we identify several key questions related to the photophysical processes and characterization methods of 2PA. The effect of laser characteristics on the nonlinear results is illustrated based on our research contributions and the future perspective and challenges in this field are also pointed out.
2023, 38(1): 97-102
doi: 10.3866/PKU.DXHX202202067
Abstract:
Based on the latest research results in the field of synthetic chemistry, a new type of catalytic tandem reactions characterized by “separation of the catalytic processes” have been developed. In such reactions, each step of the reaction takes place successively in time, and each step is independent and does not affect the others. Taking a typical reaction as an example, in this paper, the basic characteristics of this type of reaction and its importance in the field of synthetic chemistry are introduced, and a theoretical model is established to understand the kinetic characteristics of this type of reaction based on the results of quantum chemistry calculations found in the literature.
Based on the latest research results in the field of synthetic chemistry, a new type of catalytic tandem reactions characterized by “separation of the catalytic processes” have been developed. In such reactions, each step of the reaction takes place successively in time, and each step is independent and does not affect the others. Taking a typical reaction as an example, in this paper, the basic characteristics of this type of reaction and its importance in the field of synthetic chemistry are introduced, and a theoretical model is established to understand the kinetic characteristics of this type of reaction based on the results of quantum chemistry calculations found in the literature.
2023, 38(1): 103-110
doi: 10.3866/PKU.DXHX202202011
Abstract:
After the discovery in 2007, polydopamine has drawn much attention to the field of surface modification of the materials. This paper reviews the discovery process of polydopamine and its formation reactive mechanism, which further illustrates the application status of polydopamine in the field of sensing, cancer photothermal therapy, and catalysis, and the outlook of future research and applications.
After the discovery in 2007, polydopamine has drawn much attention to the field of surface modification of the materials. This paper reviews the discovery process of polydopamine and its formation reactive mechanism, which further illustrates the application status of polydopamine in the field of sensing, cancer photothermal therapy, and catalysis, and the outlook of future research and applications.
2023, 38(1): 111-118
doi: 10.3866/PKU.DXHX202203077
Abstract:
The Achmatowicz rearrangement reaction is an important organic reaction that is based on a unique oxidative rearrangement mechanism. The reaction is widely used in organic synthesis, medicinal chemistry, and other fields, and its products are important fine chemicals that are widely used in the total synthesis of complex natural products. This article reviews the mechanism underlying the Achmatowicz rearrangement reaction and its research progress, including bromine and peroxidation and participation of high valence metal oxidants, photo promotion, and enzyme-catalyzed Achmatowicz rearrangement reaction. Moreover, the future development and opportunities in this field are discussed.
The Achmatowicz rearrangement reaction is an important organic reaction that is based on a unique oxidative rearrangement mechanism. The reaction is widely used in organic synthesis, medicinal chemistry, and other fields, and its products are important fine chemicals that are widely used in the total synthesis of complex natural products. This article reviews the mechanism underlying the Achmatowicz rearrangement reaction and its research progress, including bromine and peroxidation and participation of high valence metal oxidants, photo promotion, and enzyme-catalyzed Achmatowicz rearrangement reaction. Moreover, the future development and opportunities in this field are discussed.
2023, 38(1): 119-128
doi: 10.3866/PKU.DXHX202203011
Abstract:
Proteomic cysteines play important roles in maintaining and regulating redox homeostasis in cells; they also act as functional active site in many proteins and participate in many physiological processes. In addition, post-translationally modifying proteomic cysteines also extends protein functional diversity. The development of chemical proteomics and activity-based protein profiling (ABPP) has led to many important improvements that enable cysteines and their post-translational modifications to be explored. In this paper, we briefly introduce ABPP methods for the proteome-wide profiling of cysteines, present the latest proteomics research into protein-based cysteines and their post-translational modifications, and discuss future developmental trends in this field.
Proteomic cysteines play important roles in maintaining and regulating redox homeostasis in cells; they also act as functional active site in many proteins and participate in many physiological processes. In addition, post-translationally modifying proteomic cysteines also extends protein functional diversity. The development of chemical proteomics and activity-based protein profiling (ABPP) has led to many important improvements that enable cysteines and their post-translational modifications to be explored. In this paper, we briefly introduce ABPP methods for the proteome-wide profiling of cysteines, present the latest proteomics research into protein-based cysteines and their post-translational modifications, and discuss future developmental trends in this field.
2023, 38(1): 129-140
doi: 10.3866/PKU.DXHX202202021
Abstract:
In recent years, photoelectrochemistry has attracted more and more attention as an efficient method of organic synthesis. A combination of the amazing performance of photochemical catalysis and the anti-thermodynamic properties of electrochemical catalysis has greatly simplified several organic syntheses. In this paper, we introduce typical photoelectrochemical reactions, summarize several catalysts widely applied in photoelectrochemistry, and propose a perspective for further applications of photoelectrochemistry.
In recent years, photoelectrochemistry has attracted more and more attention as an efficient method of organic synthesis. A combination of the amazing performance of photochemical catalysis and the anti-thermodynamic properties of electrochemical catalysis has greatly simplified several organic syntheses. In this paper, we introduce typical photoelectrochemical reactions, summarize several catalysts widely applied in photoelectrochemistry, and propose a perspective for further applications of photoelectrochemistry.
2023, 38(1): 141-148
doi: 10.3866/PKU.DXHX202203066
Abstract:
Blood, body fluids, and tissue samples from the human body are rich in information. Any disease or condition of the human body can be determined by detecting relevant markers; this method is called “in vitro diagnosis”. Immune diagnosis is a crucial part of in vitro diagnosis. Chemiluminescence immunoassay is one of the mainstream technologies for conducting immune diagnosis. Based on the principle of the specific binding of the antigen antibody, chemiluminescence immunoassay has good specificity and sensitivity in clinical applications as well as in food and environment domains. Herein, several in vitro diagnosis techniques are briefly introduced, with emphasis on the principle, classification, application field, and development trend of chemiluminescence immunoassay.
Blood, body fluids, and tissue samples from the human body are rich in information. Any disease or condition of the human body can be determined by detecting relevant markers; this method is called “in vitro diagnosis”. Immune diagnosis is a crucial part of in vitro diagnosis. Chemiluminescence immunoassay is one of the mainstream technologies for conducting immune diagnosis. Based on the principle of the specific binding of the antigen antibody, chemiluminescence immunoassay has good specificity and sensitivity in clinical applications as well as in food and environment domains. Herein, several in vitro diagnosis techniques are briefly introduced, with emphasis on the principle, classification, application field, and development trend of chemiluminescence immunoassay.
2023, 38(1): 149-154
doi: 10.3866/PKU.DXHX202202004
Abstract:
Colloidal gold and gold complexes play an important role in the detection and treatment of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this paper, it was described with vivid language and anthropomorphic method that the principle of immune colloidal gold technique for the determination of SARS-CoV-2 and the discovery process of gold complexes as anti-SARS-CoV-2 drugs.
Colloidal gold and gold complexes play an important role in the detection and treatment of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this paper, it was described with vivid language and anthropomorphic method that the principle of immune colloidal gold technique for the determination of SARS-CoV-2 and the discovery process of gold complexes as anti-SARS-CoV-2 drugs.
2023, 38(1): 155-160
doi: 10.3866/PKU.DXHX202201014
Abstract:
The determination of surface tension isotherm of surfactants is an important experiment of college physical chemistry laboratory. With the wide application of surfactants and the development of scientific instruments, it is necessary to update the experimental system of classical surface tension isotherm measurements. Herein, the surface tension isotherm of distearoyl phosphatidylcholine (DSPC) and dipalmitoyl phosphatidylcholine (DPPC) were determined by interfacial tensiometer, and the important parameters such as surface excess and cross-sectional area of molecules were calculated. An extended experiment was also suggested so as to promote the students’ comprehensive knowledge and cultivate the students’ ability to analyze and solve problems.
The determination of surface tension isotherm of surfactants is an important experiment of college physical chemistry laboratory. With the wide application of surfactants and the development of scientific instruments, it is necessary to update the experimental system of classical surface tension isotherm measurements. Herein, the surface tension isotherm of distearoyl phosphatidylcholine (DSPC) and dipalmitoyl phosphatidylcholine (DPPC) were determined by interfacial tensiometer, and the important parameters such as surface excess and cross-sectional area of molecules were calculated. An extended experiment was also suggested so as to promote the students’ comprehensive knowledge and cultivate the students’ ability to analyze and solve problems.
2023, 38(1): 161-168
doi: 10.3866/PKU.DXHX202201061
Abstract:
Covalent organic polymers (COPs) fluorescence materials are prepared by aldol condensation reaction, which is familiar to students. This experiment is intended to guide students to deepen the understanding of theoretical knowledge in practice, and learn to think independently and analyze the properties of fluorescent materials by using a variety of instruments. We hope this experiment can stimulate students’ imagination, make students to apply fluorescent materials to information encryption closely related to life — “eliminate the false and preserve the true”, and experience the charm of chemistry.
Covalent organic polymers (COPs) fluorescence materials are prepared by aldol condensation reaction, which is familiar to students. This experiment is intended to guide students to deepen the understanding of theoretical knowledge in practice, and learn to think independently and analyze the properties of fluorescent materials by using a variety of instruments. We hope this experiment can stimulate students’ imagination, make students to apply fluorescent materials to information encryption closely related to life — “eliminate the false and preserve the true”, and experience the charm of chemistry.
2023, 38(1): 169-173
doi: 10.3866/PKU.DXHX202201025
Abstract:
The physicochemical method is a classic experimental method in basic chemistry and also an important component of experimental training in undergraduate chemistry courses. However, existing measurement methods exhibit some drawbacks in terms of a lack of environmental protection of the experimental system, introduction of experimental errors, difficulty with controlling the operation steps, and a long experimental time. Based on green chemistry experiments and advanced, innovative, and challenging teaching requirements, the existing boiling point elevation method for measuring the molecular weight of compounds was explored. In the experiment, isopropanol instead of cyclohexane (acetone) was used as the solvent, benzoic acid instead of naphthalene was used as the solute, a water bath and electric heating rod were used for double heating, and a digital micrometer thermometer was affixed to the apparatus to improve the measurement accuracy. With these experimental improvements, the reagent was green, equipment was easy to operate, anti-interference ability of the device was strong, experimental reproducibility was good, and measurement error was reduced. Based on the foundation, the implementation of high-level, attach importance to challenges, the students’ understanding of the number dependence of dilute solution is strengthened, and their practical and innovative thinking is cultivated.
The physicochemical method is a classic experimental method in basic chemistry and also an important component of experimental training in undergraduate chemistry courses. However, existing measurement methods exhibit some drawbacks in terms of a lack of environmental protection of the experimental system, introduction of experimental errors, difficulty with controlling the operation steps, and a long experimental time. Based on green chemistry experiments and advanced, innovative, and challenging teaching requirements, the existing boiling point elevation method for measuring the molecular weight of compounds was explored. In the experiment, isopropanol instead of cyclohexane (acetone) was used as the solvent, benzoic acid instead of naphthalene was used as the solute, a water bath and electric heating rod were used for double heating, and a digital micrometer thermometer was affixed to the apparatus to improve the measurement accuracy. With these experimental improvements, the reagent was green, equipment was easy to operate, anti-interference ability of the device was strong, experimental reproducibility was good, and measurement error was reduced. Based on the foundation, the implementation of high-level, attach importance to challenges, the students’ understanding of the number dependence of dilute solution is strengthened, and their practical and innovative thinking is cultivated.
2023, 38(1): 174-179
doi: 10.3866/PKU.DXHX202201035
Abstract:
One indispensable task for higher education in the new era is to involve Values Education by Curriculum into the whole pedagogy. Chemistry laboratory classes play a significant role in undergraduate chemistry education. The synthesis of 2-nitrobenzene-1,3-diol is a classic lab session in organic chemistry. This experiment is widely performed in organic chemistry labs among a large number of universities. In this article, we describe how teachers guided students to analyze the unexpected products from side reactions in the synthesis of 2-nitrobenzene-1,3-diol laboratory class. In addition, the two most important elements of Values Education by Curriculum, scientific thinking and rigorous attitude, are explained in this process. Finally, the applications of these two elements were expanded to the whole undergraduate laboratory education in this article.
One indispensable task for higher education in the new era is to involve Values Education by Curriculum into the whole pedagogy. Chemistry laboratory classes play a significant role in undergraduate chemistry education. The synthesis of 2-nitrobenzene-1,3-diol is a classic lab session in organic chemistry. This experiment is widely performed in organic chemistry labs among a large number of universities. In this article, we describe how teachers guided students to analyze the unexpected products from side reactions in the synthesis of 2-nitrobenzene-1,3-diol laboratory class. In addition, the two most important elements of Values Education by Curriculum, scientific thinking and rigorous attitude, are explained in this process. Finally, the applications of these two elements were expanded to the whole undergraduate laboratory education in this article.
2023, 38(1): 180-186
doi: 10.3866/PKU.DXHX202201052
Abstract:
In the colloidal chemistry part of physical chemistry course, the original experiment is the preparation of iron hydroxide colloid and the determination of electrophoresis rate, which are confirmatory experiments. Furthermore, the resulting characterization of colloids is limited to electrical properties with no consideration of particle size or optical properties. In this paper, the preparation, characterization, and aggregation of soybean protein colloids were studied and the experiments were improved from the original confirmatory experiment to a comprehensive, exploratory experiment. Soybean protein colloids were prepared using the physical dispersion method, and the resulting particle size was then characterized, as well as the optical and electrical properties. Next, the aggregation and precipitation conditions were explored, and finally, tofu was produced. The particle size of the soybean protein colloids was found to be between 20–120 nm, with the most probable distribution of 51 nm, and an average charge of −41.8 mV. According to the Dindal effect, scattered blue light is observed in the direction perpendicular to the incident light, whereas the transmitted light is orange and red. By exploring the effects of counter ion types, temperature, and pH value, a deeper understanding of the colloidal precipitation process of plant protein was developed. The experiment introduces modern Zeta potential and particle size analysis, and considers protein aggregation and precipitation to extend the application of book knowledge. The final product, tofu, is closely related to life, highlighting the charm of chemistry and demonstrating the crucial role it plays in the manufacture of everyday items.
In the colloidal chemistry part of physical chemistry course, the original experiment is the preparation of iron hydroxide colloid and the determination of electrophoresis rate, which are confirmatory experiments. Furthermore, the resulting characterization of colloids is limited to electrical properties with no consideration of particle size or optical properties. In this paper, the preparation, characterization, and aggregation of soybean protein colloids were studied and the experiments were improved from the original confirmatory experiment to a comprehensive, exploratory experiment. Soybean protein colloids were prepared using the physical dispersion method, and the resulting particle size was then characterized, as well as the optical and electrical properties. Next, the aggregation and precipitation conditions were explored, and finally, tofu was produced. The particle size of the soybean protein colloids was found to be between 20–120 nm, with the most probable distribution of 51 nm, and an average charge of −41.8 mV. According to the Dindal effect, scattered blue light is observed in the direction perpendicular to the incident light, whereas the transmitted light is orange and red. By exploring the effects of counter ion types, temperature, and pH value, a deeper understanding of the colloidal precipitation process of plant protein was developed. The experiment introduces modern Zeta potential and particle size analysis, and considers protein aggregation and precipitation to extend the application of book knowledge. The final product, tofu, is closely related to life, highlighting the charm of chemistry and demonstrating the crucial role it plays in the manufacture of everyday items.
2023, 38(1): 187-191
doi: 10.3866/PKU.DXHX202202025
Abstract:
Because of the important influence of the chiral selector substitution degree on the enantioseparation of ofloxacin in chiral capillary electrophoresis experiments, the effects of the substitution degree of hydroxypropyl-β-cyclodextrin (HP-β-CD) on the inclusion complex between ofloxacin and HP-β-CD were investigated according to different substitution degrees. The results showed that the enantioseparation resolution changed significantly with the substitution degree. Moreover, the best separation resolution was found for a DS (degree of substitution) = 7.9. The methods of determining DS were also discussed. Using these methods, the quality of commercial hydroxypropyl-β-cyclodextrin products can be effectively monitored, and the stability and effectiveness in teaching of the chiral capillary electrophoresis experiment can be ensured.
Because of the important influence of the chiral selector substitution degree on the enantioseparation of ofloxacin in chiral capillary electrophoresis experiments, the effects of the substitution degree of hydroxypropyl-β-cyclodextrin (HP-β-CD) on the inclusion complex between ofloxacin and HP-β-CD were investigated according to different substitution degrees. The results showed that the enantioseparation resolution changed significantly with the substitution degree. Moreover, the best separation resolution was found for a DS (degree of substitution) = 7.9. The methods of determining DS were also discussed. Using these methods, the quality of commercial hydroxypropyl-β-cyclodextrin products can be effectively monitored, and the stability and effectiveness in teaching of the chiral capillary electrophoresis experiment can be ensured.
2023, 38(1): 192-198
doi: 10.3866/PKU.DXHX202201058
Abstract:
The undergraduate talent training plan for applied chemistry and other majors includes the use of the principles and methods of chemistry needed to realize recycling. However, there are few comprehensive experiments on recycling in the training plan. In this experiment, waste rapeseed oil and methanol are used as starting materials and sodium hydroxide and choline chloride as catalysts. The generated byproduct glycerin combines with choline chloride to form an eutectic system in situ, which is immiscible with the product/substrate phase, facilitating the fast removal of glycerin from the reaction system, and thus, promoting the reaction forward, simplifying the post-treatment process and improving the purity of the product. Moreover, the separated eutectic system can be used directly for another run. In addition, the calorific value of biodiesel is comparable to that of petrodiesel according to the results of measurements of the heat of combustion. Generally, the chemical reagents used are low-toxic and the experiment is composed of a series of fundamental operations in organic, physical and analytical chemistry experiments, and is therefore a promising experiment candidate for a comprehensive chemistry laboratory for undergraduates. This experiment also helps students to systematically understand and master the technology used and to train their initiative and exploration spirit and comprehensive practical ability. Besides, it is beneficial to integrate the ideology of environmental protection, low carbon usage and recycling into comprehensive chemistry experiment teaching.
The undergraduate talent training plan for applied chemistry and other majors includes the use of the principles and methods of chemistry needed to realize recycling. However, there are few comprehensive experiments on recycling in the training plan. In this experiment, waste rapeseed oil and methanol are used as starting materials and sodium hydroxide and choline chloride as catalysts. The generated byproduct glycerin combines with choline chloride to form an eutectic system in situ, which is immiscible with the product/substrate phase, facilitating the fast removal of glycerin from the reaction system, and thus, promoting the reaction forward, simplifying the post-treatment process and improving the purity of the product. Moreover, the separated eutectic system can be used directly for another run. In addition, the calorific value of biodiesel is comparable to that of petrodiesel according to the results of measurements of the heat of combustion. Generally, the chemical reagents used are low-toxic and the experiment is composed of a series of fundamental operations in organic, physical and analytical chemistry experiments, and is therefore a promising experiment candidate for a comprehensive chemistry laboratory for undergraduates. This experiment also helps students to systematically understand and master the technology used and to train their initiative and exploration spirit and comprehensive practical ability. Besides, it is beneficial to integrate the ideology of environmental protection, low carbon usage and recycling into comprehensive chemistry experiment teaching.
2023, 38(1): 199-205
doi: 10.3866/PKU.DXHX202202043
Abstract:
Four experimental methods, including two double-indicator methods, the BaCl2 method and the potentiometric titration method were developed for determining the mass concentration (Mass of components in unit volume of solution) of NaOH, Na2CO3 and NaHCO3 in two types of industrial mixed alkali solutions, i.e., solutions I (NaOH + Na2CO3) and II (Na2CO3 + NaHCO3). Errors and standard deviations of the four analytical methods were calculated and compared based on the measurements. Significance tests were also performed on the results of the four methods, and possible factors/causes that led to poor accuracy and significant differences were also discussed. It was concluded from the experimental results that the potentiometric titration offered the highest accuracy and precision, whereas the BaCl2 method suffered from the lowest accuracy and precision from among the four methods. The results also showed significant differences between the BaCl2 method and the other three methods. This paper not only provides a reference for the accurate determination of each component in industrial bases, but also supplies a comprehensive experimental protocol for acid-base titration teaching experiments.
Four experimental methods, including two double-indicator methods, the BaCl2 method and the potentiometric titration method were developed for determining the mass concentration (Mass of components in unit volume of solution) of NaOH, Na2CO3 and NaHCO3 in two types of industrial mixed alkali solutions, i.e., solutions I (NaOH + Na2CO3) and II (Na2CO3 + NaHCO3). Errors and standard deviations of the four analytical methods were calculated and compared based on the measurements. Significance tests were also performed on the results of the four methods, and possible factors/causes that led to poor accuracy and significant differences were also discussed. It was concluded from the experimental results that the potentiometric titration offered the highest accuracy and precision, whereas the BaCl2 method suffered from the lowest accuracy and precision from among the four methods. The results also showed significant differences between the BaCl2 method and the other three methods. This paper not only provides a reference for the accurate determination of each component in industrial bases, but also supplies a comprehensive experimental protocol for acid-base titration teaching experiments.
2023, 38(1): 206-212
doi: 10.3866/PKU.DXHX202202003
Abstract:
The devil is in the details. Although atmospheric distillation is a basic purification technique in organic chemistry, a literature search on the subject revealed that many practical details of the process are not explained in depth, whether in textbooks or articles. As a result, many students and even some teachers harbor misconceptions about distillation techniques. Based on knowledge acquired from years of practical experience in organic synthesis, this paper presents these missing details as well as common mistakes encountered throughout the distillation process, from the setup and use of the lab equipment to the distillation itself. It is hoped that this paper will facilitate fruitful discussions with peers and help students master distillation in the lab.
The devil is in the details. Although atmospheric distillation is a basic purification technique in organic chemistry, a literature search on the subject revealed that many practical details of the process are not explained in depth, whether in textbooks or articles. As a result, many students and even some teachers harbor misconceptions about distillation techniques. Based on knowledge acquired from years of practical experience in organic synthesis, this paper presents these missing details as well as common mistakes encountered throughout the distillation process, from the setup and use of the lab equipment to the distillation itself. It is hoped that this paper will facilitate fruitful discussions with peers and help students master distillation in the lab.
2023, 38(1): 213-219
doi: 10.3866/PKU.DXHX202202063
Abstract:
The preparation of organic functional materials has become one of the most important research areas in modern organic chemistry and allows the industrial manufacture of relative intermediates and products. At present, a basic organic experimental course mainly includes study of unit operations and synthesis of simple fine chemicals; extension of teaching content and promotion of engagement between education and emerging industries offer considerable strengthening the knowledge system. To this end, this project selected one of the research frontiers in organic chemistry–development of organic thermally activated delayed fluorescence (TADF) materials. This project can simultaneously supplement the existing types of organic reactions and guide students in understanding the key role of synthetic reactions in constructing organic functional materials. Furthermore, in addition to the elucidation of modern fluorescence spectroscopy technology, this project can reveal the scientific connection between organic molecular structures and the properties of organic functional materials to complete the systematic teaching of the “synthesis–molecular structure–photoelectric properties” knowledge chain. Through material preparation, structure determination, and TADF property measurement, students can not only strengthen their basic knowledge of experimental operations but also understand nuclear magnetic resonance spectrometry and fluorescence spectroscopy techniques. This experiment enriches the course of undergraduate organic experiments and allows students to experience the complete scientific research process, thus facilitating the formation of a gradient, multi-disciplinary knowledge system.
The preparation of organic functional materials has become one of the most important research areas in modern organic chemistry and allows the industrial manufacture of relative intermediates and products. At present, a basic organic experimental course mainly includes study of unit operations and synthesis of simple fine chemicals; extension of teaching content and promotion of engagement between education and emerging industries offer considerable strengthening the knowledge system. To this end, this project selected one of the research frontiers in organic chemistry–development of organic thermally activated delayed fluorescence (TADF) materials. This project can simultaneously supplement the existing types of organic reactions and guide students in understanding the key role of synthetic reactions in constructing organic functional materials. Furthermore, in addition to the elucidation of modern fluorescence spectroscopy technology, this project can reveal the scientific connection between organic molecular structures and the properties of organic functional materials to complete the systematic teaching of the “synthesis–molecular structure–photoelectric properties” knowledge chain. Through material preparation, structure determination, and TADF property measurement, students can not only strengthen their basic knowledge of experimental operations but also understand nuclear magnetic resonance spectrometry and fluorescence spectroscopy techniques. This experiment enriches the course of undergraduate organic experiments and allows students to experience the complete scientific research process, thus facilitating the formation of a gradient, multi-disciplinary knowledge system.
2023, 38(1): 220-226
doi: 10.3866/PKU.DXHX202203020
Abstract:
In this experiment, pyrrolidine and 4-dimethylaminobenzoic acid were used as organic small molecule catalysts to catalyze the Aldol condensation and dehydration of natural fragrance (+/−)-citronellal with formaldehyde to synthesize (+/−)-2-methylene citronellal. Based on the hydrogen bond induction effect, the solvents dichloromethane, tetrahydrofuran, and anhydrous ethanol were selected for use in parallel reactions. All the reactions were monitored by thin-layer chromatography, and the relatively optimal reaction solvent was determined. Simultaneously, we used the resonance delocalization theory to explain the difference in the NMR chemical shifts, thin layer chromatography ratio shifts, and liquid chromatography retention times of raw materials and products. This experiment fills the gap in the optimization of reaction conditions in organic chemistry experiments.
In this experiment, pyrrolidine and 4-dimethylaminobenzoic acid were used as organic small molecule catalysts to catalyze the Aldol condensation and dehydration of natural fragrance (+/−)-citronellal with formaldehyde to synthesize (+/−)-2-methylene citronellal. Based on the hydrogen bond induction effect, the solvents dichloromethane, tetrahydrofuran, and anhydrous ethanol were selected for use in parallel reactions. All the reactions were monitored by thin-layer chromatography, and the relatively optimal reaction solvent was determined. Simultaneously, we used the resonance delocalization theory to explain the difference in the NMR chemical shifts, thin layer chromatography ratio shifts, and liquid chromatography retention times of raw materials and products. This experiment fills the gap in the optimization of reaction conditions in organic chemistry experiments.
2023, 38(1): 227-232
doi: 10.3866/PKU.DXHX202203034
Abstract:
Based on the activation energy of the reaction occurring at the electrode, the structure of the glassy carbon electrode (GCE) surface changes before and after pre-anodization and hydrogen bonding catalysis. This causes differences in the voltammograms of acetaminophen measured before and after pre-anodization using a GCE. These differences are discussed in this paper by applying the inquiry teaching mode, whicn can not only improve the quality of delivering chemistry experiments but also the teachers’ instructional skills.
Based on the activation energy of the reaction occurring at the electrode, the structure of the glassy carbon electrode (GCE) surface changes before and after pre-anodization and hydrogen bonding catalysis. This causes differences in the voltammograms of acetaminophen measured before and after pre-anodization using a GCE. These differences are discussed in this paper by applying the inquiry teaching mode, whicn can not only improve the quality of delivering chemistry experiments but also the teachers’ instructional skills.
2023, 38(1): 233-239
doi: 10.3866/PKU.DXHX202201019
Abstract:
The extraction of Rutin from Sophora japonica buds is a classic experiment performed in basic organic chemistry for the extraction of flavonoids from plants. The molecular structure of a series of flavonoid drugs extracted from plants, which are derived from 2-phenylchromogenone (also known as flavone) molecules, were analyzed. In the experiment, we found that the extraction yield of flavonoids is low and could not satisfy the current demand for flavonoid drugs. Therefore, we attempted to synthesize flavonoids and their corresponding derivatives using a high efficiency chemical method. Flavonoid synthesis was divided into two steps. First, 2’-hydroxychalcone was synthesized by aldol condensation, followed by the cyclization of iodine-catalyzed molecules to produce flavone. This experiment requires approximately 6 h to complete and can be used as a teaching experiment, as well as a development and open experiment after class. The improved experiment has the advantages of safety, easy operation, good repeatability, and high yield compared with the extraction from plants. In addition, through the improvement of this experiment, the students were guided to adopt a similar method to design and synthesize the flavonoid derivative “efloxatem” (the main active component in angina pectoris). This experiment enriched the teaching content of organic chemistry experiments, improved students’ analytical ability, and cultivated their spirit of scientific exploration.
The extraction of Rutin from Sophora japonica buds is a classic experiment performed in basic organic chemistry for the extraction of flavonoids from plants. The molecular structure of a series of flavonoid drugs extracted from plants, which are derived from 2-phenylchromogenone (also known as flavone) molecules, were analyzed. In the experiment, we found that the extraction yield of flavonoids is low and could not satisfy the current demand for flavonoid drugs. Therefore, we attempted to synthesize flavonoids and their corresponding derivatives using a high efficiency chemical method. Flavonoid synthesis was divided into two steps. First, 2’-hydroxychalcone was synthesized by aldol condensation, followed by the cyclization of iodine-catalyzed molecules to produce flavone. This experiment requires approximately 6 h to complete and can be used as a teaching experiment, as well as a development and open experiment after class. The improved experiment has the advantages of safety, easy operation, good repeatability, and high yield compared with the extraction from plants. In addition, through the improvement of this experiment, the students were guided to adopt a similar method to design and synthesize the flavonoid derivative “efloxatem” (the main active component in angina pectoris). This experiment enriched the teaching content of organic chemistry experiments, improved students’ analytical ability, and cultivated their spirit of scientific exploration.
2023, 38(1): 240-247
doi: 10.3866/PKU.DXHX202201018
Abstract:
We design a comprehensive chemical experiment case, including catalyst preparation, instrumental characterization, and catalytic performance evaluation, to deepen students’ understanding of the catalytic chemistry and make the traditional teaching on catalysis more stereoscopic. This experiment case involves the preparation of CuO/TiO2 catalysts by a deposition-precipitation method, the structure characterization of the catalyst by Raman spectroscopy, and the evaluation of the catalytic performance of CO oxidation reaction. From this experiment task, students can establish a preliminary understanding of the relationship of “structure-performance”, improve the practice ability, and lay a foundation for future scientific research.
We design a comprehensive chemical experiment case, including catalyst preparation, instrumental characterization, and catalytic performance evaluation, to deepen students’ understanding of the catalytic chemistry and make the traditional teaching on catalysis more stereoscopic. This experiment case involves the preparation of CuO/TiO2 catalysts by a deposition-precipitation method, the structure characterization of the catalyst by Raman spectroscopy, and the evaluation of the catalytic performance of CO oxidation reaction. From this experiment task, students can establish a preliminary understanding of the relationship of “structure-performance”, improve the practice ability, and lay a foundation for future scientific research.
2023, 38(1): 248-253
doi: 10.3866/PKU.DXHX202201032
Abstract:
This paper investigates the reference bibliographies related to laboratory safety, analyzes the current construction situation laboratory safety teaching materials at home and abroad in recent years. By combining with the current status of laboratory safety education and management, suggestions for the compilation of relevant teaching materials including strengthening the popularization of laboratory safety laws, regulations and standards, and resource integration, have been put forward.
This paper investigates the reference bibliographies related to laboratory safety, analyzes the current construction situation laboratory safety teaching materials at home and abroad in recent years. By combining with the current status of laboratory safety education and management, suggestions for the compilation of relevant teaching materials including strengthening the popularization of laboratory safety laws, regulations and standards, and resource integration, have been put forward.
2023, 38(1): 254-261
doi: 10.3866/PKU.DXHX202201056
Abstract:
In the teaching of organic chemistry, the pericyclic reaction involves learning a large amount of theory, with a focus on explaining the reaction mechanisms in terms of molecular orbitals, apart from analyzing functional groups. The use of quantum mechanics to explain the pericyclic reaction is helpful as it can predict the products and design the synthetic route. However, classroom teaching can face immense challenges in this regard, due to the abstract theory and confusing application prospects of quantum mechanics. This article attempts to rationally simplify the complex principle of the pericyclic reaction and elucidate it from the point of view of synthesis applications. Classic cases of scientific practice in teaching, such as Fukui’s observation and prediction, Dewar-benzene conversion, and VB12 synthesis are discussed. This methodology would not only enable students to understand basic principles in depth, but also cultivate in them a scientific and systematic thinking approach to solve complex problems.
In the teaching of organic chemistry, the pericyclic reaction involves learning a large amount of theory, with a focus on explaining the reaction mechanisms in terms of molecular orbitals, apart from analyzing functional groups. The use of quantum mechanics to explain the pericyclic reaction is helpful as it can predict the products and design the synthetic route. However, classroom teaching can face immense challenges in this regard, due to the abstract theory and confusing application prospects of quantum mechanics. This article attempts to rationally simplify the complex principle of the pericyclic reaction and elucidate it from the point of view of synthesis applications. Classic cases of scientific practice in teaching, such as Fukui’s observation and prediction, Dewar-benzene conversion, and VB12 synthesis are discussed. This methodology would not only enable students to understand basic principles in depth, but also cultivate in them a scientific and systematic thinking approach to solve complex problems.
2023, 38(1): 262-267
doi: 10.3866/PKU.DXHX202202035
Abstract:
Short answer questions are commonly seen in exercises and examinations in analytical chemistry. The usual way to solve this type of question is by expressing the argument verbally, which can lead to a lack in clarity and can easily generate ambiguity. In this paper, a method for solving this type of question using mathematical analysis based on the perception of quantity is shown. This will make the solution more rigorous and easier to understand.
Short answer questions are commonly seen in exercises and examinations in analytical chemistry. The usual way to solve this type of question is by expressing the argument verbally, which can lead to a lack in clarity and can easily generate ambiguity. In this paper, a method for solving this type of question using mathematical analysis based on the perception of quantity is shown. This will make the solution more rigorous and easier to understand.
2023, 38(1): 268-279
doi: 10.3866/PKU.DXHX202202051
Abstract:
We discuss in detail the meaning of “parent hydride” and “characteristic group”, two terms used in organic chemistry. Through numerous examples, we demonstrate that nomenclature based on parent hydrides is superior in terms of convenience, systematization, and clarity. We also propose that “characteristic group” is a more accurate term than the commonly used “functional group” because each atom can only be described once.
We discuss in detail the meaning of “parent hydride” and “characteristic group”, two terms used in organic chemistry. Through numerous examples, we demonstrate that nomenclature based on parent hydrides is superior in terms of convenience, systematization, and clarity. We also propose that “characteristic group” is a more accurate term than the commonly used “functional group” because each atom can only be described once.
2023, 38(1): 280-286
doi: 10.3866/PKU.DXHX202202072
Abstract:
Limited by the decomposition voltage of water (1.23 V), the open-circuit voltage of aqueous secondary batteries is generally low. Through the analysis of factors influencing the open-circuit voltage of aqueous secondary batteries, several new strategies to improve the open-circuit voltage are introduced in this paper. In addition, the advantages and disadvantages of each strategy are discussed.
Limited by the decomposition voltage of water (1.23 V), the open-circuit voltage of aqueous secondary batteries is generally low. Through the analysis of factors influencing the open-circuit voltage of aqueous secondary batteries, several new strategies to improve the open-circuit voltage are introduced in this paper. In addition, the advantages and disadvantages of each strategy are discussed.
2023, 38(1): 287-294
doi: 10.3866/PKU.DXHX202203067
Abstract:
This paper, taking “Schroödinger equation of single electron atom” as an example, introduces an open-source web platform called Jupyter for teaching structural chemistry, which integrates knowledge presentation, scientific calculation, and data visualization. Assisted by various Python libraries, students can interactively learn theoretical concepts, deduce mathematical formulae, and understand the nature of wave functions, which can enhance the participation and interactivity of structural chemistry teaching and cultivate students’ programming ability to solve scientific problems.
This paper, taking “Schroödinger equation of single electron atom” as an example, introduces an open-source web platform called Jupyter for teaching structural chemistry, which integrates knowledge presentation, scientific calculation, and data visualization. Assisted by various Python libraries, students can interactively learn theoretical concepts, deduce mathematical formulae, and understand the nature of wave functions, which can enhance the participation and interactivity of structural chemistry teaching and cultivate students’ programming ability to solve scientific problems.
2023, 38(1): 295-303
doi: 10.3866/PKU.DXHX202201046
Abstract:
In order to extend innovation and entrepreneurship education and practice, cultivate the students’ innovation and entrepreneurship ability, improve undergraduate education quality, and further promote the reform of innovation and entrepreneurship education, a project called “National College Students’ Innovation and Entrepreneurship Training Program” has been carried out in Nankai University. In addition to details of the chemical discipline, methods for integrating science and education, as well as integrating theory with practice have been taught in the college of chemistry. In this program, undergraduates were not only guided to actively participate in scientific research training, but also to apply their innovative results in practice. A unified system of mutual complementarity and mutual promotion between “scientific research feeding into teaching” and “teaching supporting scientific research” has been realized. In this paper, a typical example of undergraduate students participating in this training program is introduced. Details from the preparation to the specific implementation process of the program, including difficulties, experiences, and successes of the project are shown, with the hopes of sharing our experience with other undergraduates majoring in chemistry and helping them improve their innovative projects.
In order to extend innovation and entrepreneurship education and practice, cultivate the students’ innovation and entrepreneurship ability, improve undergraduate education quality, and further promote the reform of innovation and entrepreneurship education, a project called “National College Students’ Innovation and Entrepreneurship Training Program” has been carried out in Nankai University. In addition to details of the chemical discipline, methods for integrating science and education, as well as integrating theory with practice have been taught in the college of chemistry. In this program, undergraduates were not only guided to actively participate in scientific research training, but also to apply their innovative results in practice. A unified system of mutual complementarity and mutual promotion between “scientific research feeding into teaching” and “teaching supporting scientific research” has been realized. In this paper, a typical example of undergraduate students participating in this training program is introduced. Details from the preparation to the specific implementation process of the program, including difficulties, experiences, and successes of the project are shown, with the hopes of sharing our experience with other undergraduates majoring in chemistry and helping them improve their innovative projects.
