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2019 Volume 34 Issue 7
2019, 34(7): 1-5
doi: 10.3866/PKU.DXHX201901023
Abstract:
Aiming at the dilemma of the traditional university chemistry teaching mode, this paper explores the multi-dimensional teaching mode from the perspective of "student-centered" and "process management". The teaching mode focuses on the four dimensions of "acceptance, application and expansion" of knowledge and "improvement" of ability. It introduces eight teaching sections, including classroom teaching, classroom practice, classroom question and answer, tutoring and answering after class, homework, classroom speech, course essay and extracurricular practice. This teaching mode has achieved initial results and provided an opportunity for students to expand their knowledge and enhance their ability.
Aiming at the dilemma of the traditional university chemistry teaching mode, this paper explores the multi-dimensional teaching mode from the perspective of "student-centered" and "process management". The teaching mode focuses on the four dimensions of "acceptance, application and expansion" of knowledge and "improvement" of ability. It introduces eight teaching sections, including classroom teaching, classroom practice, classroom question and answer, tutoring and answering after class, homework, classroom speech, course essay and extracurricular practice. This teaching mode has achieved initial results and provided an opportunity for students to expand their knowledge and enhance their ability.
2019, 34(7): 6-10
doi: 10.3866/PKU.DXHX201812018
Abstract:
In view of the increasing quantity of MOOC curriculum construction and the utilization of MOOC resources, this paper puts forward how to efficiently make use of MOOC resources through deepening curriculum teaching reform. In this paper, the problems in MOOC teaching are summarized, and then the SPOC course is introduced. Along with introducing SPOC course, taking the course of inorganic and analytical chemistry in Huazhong Agricultural University as an example, four main functions of SPOC are expounded emphatically which include solving the problem of cultivating students' autonomous learning ability, solving the problem of obtaining knowledge from MOOC in a piecemeal way, solving the concern about the effect of online learning and solving the low participation of MOOC. It is concluded that the course of SPOC is an important way to make good use of MOOC. It is suggested that the co-construction and sharing of MOOC should be strengthened to enhance the efficiency of MOOC.
In view of the increasing quantity of MOOC curriculum construction and the utilization of MOOC resources, this paper puts forward how to efficiently make use of MOOC resources through deepening curriculum teaching reform. In this paper, the problems in MOOC teaching are summarized, and then the SPOC course is introduced. Along with introducing SPOC course, taking the course of inorganic and analytical chemistry in Huazhong Agricultural University as an example, four main functions of SPOC are expounded emphatically which include solving the problem of cultivating students' autonomous learning ability, solving the problem of obtaining knowledge from MOOC in a piecemeal way, solving the concern about the effect of online learning and solving the low participation of MOOC. It is concluded that the course of SPOC is an important way to make good use of MOOC. It is suggested that the co-construction and sharing of MOOC should be strengthened to enhance the efficiency of MOOC.
2019, 34(7): 11-15
doi: 10.3866/PKU.DXHX201901027
Abstract:
In the past practical training courses, the courses were separated from the industry. Professional teachers in the school had no industry background, and industrial instructors lacked the ability of curriculum design. Focusing on these problems, as well as the demand for applied talents, new practical training courses are urgently needed. Taking the practical training course of "analytical detection technique" as an example, the paper explores the application of project-driven teaching model to realize the transformation from knowledge paradigm to ability paradigm. Finally, it will cultivate applied talents to meet the needs of social developments and industry demands.
In the past practical training courses, the courses were separated from the industry. Professional teachers in the school had no industry background, and industrial instructors lacked the ability of curriculum design. Focusing on these problems, as well as the demand for applied talents, new practical training courses are urgently needed. Taking the practical training course of "analytical detection technique" as an example, the paper explores the application of project-driven teaching model to realize the transformation from knowledge paradigm to ability paradigm. Finally, it will cultivate applied talents to meet the needs of social developments and industry demands.
2019, 34(7): 16-22
doi: 10.3866/PKU.DXHX201901015
Abstract:
The construction of application-based courses is one of the keys to the development of application-oriented universities. In this paper, the construction of the project-driven "Cosmetics and Spices" course was introduced. Its construction content from the four modules of theory, experiment, open experiment, enterprise project-oriented curriculum design and maker education was explored, and corresponding implementation plans of application-based courses were proposed.
The construction of application-based courses is one of the keys to the development of application-oriented universities. In this paper, the construction of the project-driven "Cosmetics and Spices" course was introduced. Its construction content from the four modules of theory, experiment, open experiment, enterprise project-oriented curriculum design and maker education was explored, and corresponding implementation plans of application-based courses were proposed.
2019, 34(7): 23-30
doi: 10.3866/PKU.DXHX201901030
Abstract:
Colligative properties of dilute solutions are the basic contents for chemistry, chemical engineering and biomedicine majors. The teaching model of multidimensional interact takes teachers as the leader and students as the main body. Through the multi-dimensional interaction among teachers and students, students and groups, students' interest in learning, strong sense of cooperation and independent learning ability can be cultivated. This paper introduces the implementation process of the multi-dimensional interactive teaching mode of "colligative properties of dilute solutions", which includes clarifying the purpose of interaction, constructing learning groups, raising interactive questions, launching interactive activities and implementing interactive evaluation, etc. Multi-dimensional teaching goals can be achieved through group explorations, group presentations and group discussions.
Colligative properties of dilute solutions are the basic contents for chemistry, chemical engineering and biomedicine majors. The teaching model of multidimensional interact takes teachers as the leader and students as the main body. Through the multi-dimensional interaction among teachers and students, students and groups, students' interest in learning, strong sense of cooperation and independent learning ability can be cultivated. This paper introduces the implementation process of the multi-dimensional interactive teaching mode of "colligative properties of dilute solutions", which includes clarifying the purpose of interaction, constructing learning groups, raising interactive questions, launching interactive activities and implementing interactive evaluation, etc. Multi-dimensional teaching goals can be achieved through group explorations, group presentations and group discussions.
2019, 34(7): 31-37
doi: 10.3866/PKU.DXHX201902008
Abstract:
Multi-dimensional interactive teaching mode focuses on the teacher-student and student-student interactions. It implements the education conception of student as the subject and teacher as the guider. It is an effective way to cultivate high quality individuals with innovative and practical abilities. This paper sets forth the necessity and measures to carry out the multi-dimensional interactive teaching mode in the laboratory teaching of preparation of ferrous ammonium sulfate. The measures include defining the teaching aim, asking interactive questions, experiencing interactive activities and conducting interactive evaluation. Those measures make it possible to achieve the goals of promoting the students' comprehensive development of knowledge, ability, emotion, attitude as well as personal integrity.
Multi-dimensional interactive teaching mode focuses on the teacher-student and student-student interactions. It implements the education conception of student as the subject and teacher as the guider. It is an effective way to cultivate high quality individuals with innovative and practical abilities. This paper sets forth the necessity and measures to carry out the multi-dimensional interactive teaching mode in the laboratory teaching of preparation of ferrous ammonium sulfate. The measures include defining the teaching aim, asking interactive questions, experiencing interactive activities and conducting interactive evaluation. Those measures make it possible to achieve the goals of promoting the students' comprehensive development of knowledge, ability, emotion, attitude as well as personal integrity.
2019, 34(7): 38-41
doi: 10.3866/PKU.DXHX201902001
Abstract:
The "Senior High School Students Elite Program" is a training program developed by the state to train top-notch talents for scientific and technological innovation. This paper summarized the training situation of elite students in the past three years, and put forward a progression education mode. We hope that this education mode will truly benefit those senior high school students who have a strong interest in scientific research, so that the "Senior High School Students Elite Program" can be developed well and provide reference significance to realize its original intention.
The "Senior High School Students Elite Program" is a training program developed by the state to train top-notch talents for scientific and technological innovation. This paper summarized the training situation of elite students in the past three years, and put forward a progression education mode. We hope that this education mode will truly benefit those senior high school students who have a strong interest in scientific research, so that the "Senior High School Students Elite Program" can be developed well and provide reference significance to realize its original intention.
2019, 34(7): 42-46
doi: 10.3866/PKU.DXHX201901024
Abstract:
Under the background of establishing the emerging engineering education, teaching of organic chemistry in engineering specialties needs innovation. Efforts have been made to improve the teaching effect of organic chemistry, including selecting textbooks and teaching contents, reforming teaching methods, improving assessment system, and making the best of organic chemistry laboratory course.
Under the background of establishing the emerging engineering education, teaching of organic chemistry in engineering specialties needs innovation. Efforts have been made to improve the teaching effect of organic chemistry, including selecting textbooks and teaching contents, reforming teaching methods, improving assessment system, and making the best of organic chemistry laboratory course.
2019, 34(7): 47-51
doi: 10.3866/PKU.DXHX201901026
Abstract:
Super-star learning assisted sectionalized examinations were carried out in university organic chemistry course. The passing rate and excellent rate of final examination of organic chemistry course have been effectively improved. This strategy emphasizes the accumulation of knowledge in normal learning which can improve students' active learning ability and teaching quality.
Super-star learning assisted sectionalized examinations were carried out in university organic chemistry course. The passing rate and excellent rate of final examination of organic chemistry course have been effectively improved. This strategy emphasizes the accumulation of knowledge in normal learning which can improve students' active learning ability and teaching quality.
2019, 34(7): 52-59
doi: 10.3866/PKU.DXHX201902012
Abstract:
In order to improve the quality of teaching and cultivate chemical innovation talents in university for nationalities, in the course of organic synthetic chemistry curriculum construction, efforts were made to overcome problems such as the single teaching objective, abstract and boring teaching content, tedious and relatively dull teaching methods and low enthusiasm for students' learning, etc. According to the study rule of "before class-on class-after class", the trinity mixed teaching mode of "teaching goal-teaching means-practice examination" was constructed. Through the construction of the "teaching goal-teaching means-innovative practice" trinity mixed teaching mode, we refined teaching objectives, optimized teaching methods, implemented small classes, improved assessment methods, designed comprehensive laboratory programs, reinforced practices, and reformed the assessment measures. Discussion on teaching reform and practice of organic synthetic chemistry was carried out from multiple perspectives. Through the practice of teaching reform, the teaching effect has been improved, the enthusiasm of students to learn organic synthetic chemistry has been improved, and the expected effect of cultivating students' innovative ability has been achieved.
In order to improve the quality of teaching and cultivate chemical innovation talents in university for nationalities, in the course of organic synthetic chemistry curriculum construction, efforts were made to overcome problems such as the single teaching objective, abstract and boring teaching content, tedious and relatively dull teaching methods and low enthusiasm for students' learning, etc. According to the study rule of "before class-on class-after class", the trinity mixed teaching mode of "teaching goal-teaching means-practice examination" was constructed. Through the construction of the "teaching goal-teaching means-innovative practice" trinity mixed teaching mode, we refined teaching objectives, optimized teaching methods, implemented small classes, improved assessment methods, designed comprehensive laboratory programs, reinforced practices, and reformed the assessment measures. Discussion on teaching reform and practice of organic synthetic chemistry was carried out from multiple perspectives. Through the practice of teaching reform, the teaching effect has been improved, the enthusiasm of students to learn organic synthetic chemistry has been improved, and the expected effect of cultivating students' innovative ability has been achieved.
2019, 34(7): 60-66
doi: 10.3866/PKU.DXHX201812025
Abstract:
In eukaryotes, the ubiquitin-proteasome pathway degrades the majority of intracellular proteins tagged with polyubiquitin chains. It participates in regulation of key cellular activities, such as cell proliferation, cell differentiation, apoptosis, DNA repair, etc. through the degradation of malformed or misfolded proteins. Dysfunctions of the ubiquitin-proteasome pathway have been linked to many diseases, including cancer and neurodegeneration, etc. The commercially available proteasome inhibitors have been successfully used to treat multiple myeloma and mantle cell lymphoma. In addition, novel inhibitors against other components of the ubiquitin-proteasome pathway, such as those enzymes that drive ubiquitination and deubiquitination in preclinical testing or clinical trials, exhibit promising therapeutic effects in vivo. This paper briefly introduces the ubiquitin-proteasome pathway related drug discovery progress.
In eukaryotes, the ubiquitin-proteasome pathway degrades the majority of intracellular proteins tagged with polyubiquitin chains. It participates in regulation of key cellular activities, such as cell proliferation, cell differentiation, apoptosis, DNA repair, etc. through the degradation of malformed or misfolded proteins. Dysfunctions of the ubiquitin-proteasome pathway have been linked to many diseases, including cancer and neurodegeneration, etc. The commercially available proteasome inhibitors have been successfully used to treat multiple myeloma and mantle cell lymphoma. In addition, novel inhibitors against other components of the ubiquitin-proteasome pathway, such as those enzymes that drive ubiquitination and deubiquitination in preclinical testing or clinical trials, exhibit promising therapeutic effects in vivo. This paper briefly introduces the ubiquitin-proteasome pathway related drug discovery progress.
2019, 34(7): 67-72
doi: 10.3866/PKU.DXHX201812009
Abstract:
As a new type of nano-materials, carbon dots have unique optical properties and excellent chemical properties, such as easy preparation, low cost, high chemical stability and good biocompatibility. Three kinds of carbon dots were prepared by microwave, hydrothermal and pyrolysis methods, and characterized by infrared spectroscopy. The ultraviolet-visible absorption spectra and fluorescence spectra of the three carbon dots were measured and compared with those of small organic fluorescent molecules. The fluorescence quantum yield of three carbon dots was measured using quinine sulfate as standards. This experiment not only enables students to learn the preparation methods and the unique luminescent properties of carbon nanomaterials, but also enables students to have a deeper understanding of the structures, principles and applications of three kinds of molecular spectroscopy instruments based on the measurement of quantum yield. This experiment can be used as a comprehensive 10-hour instrumental analysis experiment for junior students majoring in chemistry, applied chemistry and material chemistry.
As a new type of nano-materials, carbon dots have unique optical properties and excellent chemical properties, such as easy preparation, low cost, high chemical stability and good biocompatibility. Three kinds of carbon dots were prepared by microwave, hydrothermal and pyrolysis methods, and characterized by infrared spectroscopy. The ultraviolet-visible absorption spectra and fluorescence spectra of the three carbon dots were measured and compared with those of small organic fluorescent molecules. The fluorescence quantum yield of three carbon dots was measured using quinine sulfate as standards. This experiment not only enables students to learn the preparation methods and the unique luminescent properties of carbon nanomaterials, but also enables students to have a deeper understanding of the structures, principles and applications of three kinds of molecular spectroscopy instruments based on the measurement of quantum yield. This experiment can be used as a comprehensive 10-hour instrumental analysis experiment for junior students majoring in chemistry, applied chemistry and material chemistry.
2019, 34(7): 73-78
doi: 10.3866/PKU.DXHX201901021
Abstract:
The experiment of separating low toxic n-hexane and cyclohexane by traditional gas chromatography was improved with orthogonal experimental design. The effect of sample quantity, vaporization chamber temperature, detector temperature, column temperature, line velocity and separability of the split ratio were examined. Through the experiment, students could understand the use and maintenance of gas chromatography instruments. At the same time, they could understand separability and column efficiency of chromatography.
The experiment of separating low toxic n-hexane and cyclohexane by traditional gas chromatography was improved with orthogonal experimental design. The effect of sample quantity, vaporization chamber temperature, detector temperature, column temperature, line velocity and separability of the split ratio were examined. Through the experiment, students could understand the use and maintenance of gas chromatography instruments. At the same time, they could understand separability and column efficiency of chromatography.
2019, 34(7): 79-84
doi: 10.3866/PKU.DXHX201901033
Abstract:
In order to explore the optimum preparation conditions, effects of FeCl3 dosage, hydrolysis temperature and dialysis time on the particle size, conductivity, pH and double layer potential (ζ) of Fe(OH）3 sol were systematically studied. The ultraviolet-visible reflection spectrophotometry was used to track the particle size of Fe(OH）3 sol. With the increase of FeCl3 dosage, the particle size of the colloid increased, the reflectivity decreased and the reflection wavelength shifted to longer wavelength, which is in accordance with the quantum confinement effect theory. The excessive Cl- would inhibit the conductivity, and the stability of Fe(OH）3 sol with larger particle size would be worse. Because of the better synergistic effect of q/m and V/l under the action of electric field of 80 V with electrophoresis, the ζ of the Fe(OH）3 sol prepared under the optimum conditions (cFeCl3, 0.01 mol·L-1; 100℃; dialysis time, 1 d) was 43.67 mV which was most close to the theoretical value of 44.00 mV.
In order to explore the optimum preparation conditions, effects of FeCl3 dosage, hydrolysis temperature and dialysis time on the particle size, conductivity, pH and double layer potential (ζ) of Fe(OH）3 sol were systematically studied. The ultraviolet-visible reflection spectrophotometry was used to track the particle size of Fe(OH）3 sol. With the increase of FeCl3 dosage, the particle size of the colloid increased, the reflectivity decreased and the reflection wavelength shifted to longer wavelength, which is in accordance with the quantum confinement effect theory. The excessive Cl- would inhibit the conductivity, and the stability of Fe(OH）3 sol with larger particle size would be worse. Because of the better synergistic effect of q/m and V/l under the action of electric field of 80 V with electrophoresis, the ζ of the Fe(OH）3 sol prepared under the optimum conditions (cFeCl3, 0.01 mol·L-1; 100℃; dialysis time, 1 d) was 43.67 mV which was most close to the theoretical value of 44.00 mV.
2019, 34(7): 85-89
doi: 10.3866/PKU.DXHX201812016
Abstract:
Organic chemistry is an important course for chemistry related disciplines but it is difficult to study. With the diverse reaction conditions and types, pithy formulas were suggested to help memorization. During the programming of the pithy formulas, the various meanings of Chinese characters and the association ability of human brain were fully considered, making the pithy formulas simple and easy to read. The scattered information was organized, making the abstract reactions readily remembered. The pithy formulas can not only get beginners familiar with organic chemistry, but also be useful for knowledge system constructing, helping knowledge comprehension and application lifelong.
Organic chemistry is an important course for chemistry related disciplines but it is difficult to study. With the diverse reaction conditions and types, pithy formulas were suggested to help memorization. During the programming of the pithy formulas, the various meanings of Chinese characters and the association ability of human brain were fully considered, making the pithy formulas simple and easy to read. The scattered information was organized, making the abstract reactions readily remembered. The pithy formulas can not only get beginners familiar with organic chemistry, but also be useful for knowledge system constructing, helping knowledge comprehension and application lifelong.
2019, 34(7): 90-94
doi: 10.3866/PKU.DXHX201812011
Abstract:
In the time order, the author proposes that the discovery and development of the periodic table of chemical elements are divided into four stages:point→1D→2D→3D. This article cites the main historical facts and documents available to unscramble the above four stages, which will facilitate the teaching and scientific research of the periodic table.
In the time order, the author proposes that the discovery and development of the periodic table of chemical elements are divided into four stages:point→1D→2D→3D. This article cites the main historical facts and documents available to unscramble the above four stages, which will facilitate the teaching and scientific research of the periodic table.
2019, 34(7): 95-99
doi: 10.3866/PKU.DXHX201901034
Abstract:
The oxidation state of iron in the "brown-ring" reaction product[Fe(NO)(H2O）5]2+ and the bond between Fe and NO in this cation are discussed in detail. After presenting different views from the literature based on experimental evidences and theoretical calculations, the oxidation state of iron resonates between +2 and +3 inclining to +2. The Fe-N-O bond angle is 180°. In addition, we proposed an explanation for the slightly shortening of the bond length of NO after coordination to the iron ion.
The oxidation state of iron in the "brown-ring" reaction product[Fe(NO)(H2O）5]2+ and the bond between Fe and NO in this cation are discussed in detail. After presenting different views from the literature based on experimental evidences and theoretical calculations, the oxidation state of iron resonates between +2 and +3 inclining to +2. The Fe-N-O bond angle is 180°. In addition, we proposed an explanation for the slightly shortening of the bond length of NO after coordination to the iron ion.
2019, 34(7): 100-104
doi: 10.3866/PKU.DXHX201812002
Abstract:
Using three-dimensional (3D) graphing and molecular modeling softwares, the procedures for presenting the VRML 3D wave functions have been discussed. The interactivities of VRML can help students to observe the characters of wave functions intuitively, which also improve the teaching results of quantum chemistry and electronic structures effectively.
Using three-dimensional (3D) graphing and molecular modeling softwares, the procedures for presenting the VRML 3D wave functions have been discussed. The interactivities of VRML can help students to observe the characters of wave functions intuitively, which also improve the teaching results of quantum chemistry and electronic structures effectively.
2019, 34(7): 105-108
doi: 10.3866/PKU.DXHX201812027
Abstract:
In this paper, an Origin mapping method is introduced, which can directly draw the Renolds temperature correction chart in the combustion heat measurement experiment for further data process. Compared with manual drawing, Origin has the advantages of high accuracy, simplicity and rapidity. Compared with the computer multi-segment linear fitting method, Origin not only has the same high accuracy, but also is more intuitive, reflecting the original intention of Renolds mapping method better, and can directly observe the heat leakage of combustion heat experiment. Origin's method of directly drawing Renolds temperature correction diagram has the advantages of both manual drawing and computer linear fitting, and it is worth popularizing.
In this paper, an Origin mapping method is introduced, which can directly draw the Renolds temperature correction chart in the combustion heat measurement experiment for further data process. Compared with manual drawing, Origin has the advantages of high accuracy, simplicity and rapidity. Compared with the computer multi-segment linear fitting method, Origin not only has the same high accuracy, but also is more intuitive, reflecting the original intention of Renolds mapping method better, and can directly observe the heat leakage of combustion heat experiment. Origin's method of directly drawing Renolds temperature correction diagram has the advantages of both manual drawing and computer linear fitting, and it is worth popularizing.
2019, 34(7): 109-116
doi: 10.3866/PKU.DXHX201903010
Abstract:
Scientific theory innovation needs scientists who have comprehensive critical thinking. Taking the history of science of phlogiston and periodic law of elements as an example, this paper expounds the role of the critical thinking skills and habits, and tries to develop the way for acquisition of critical thinking from the history of science.
Scientific theory innovation needs scientists who have comprehensive critical thinking. Taking the history of science of phlogiston and periodic law of elements as an example, this paper expounds the role of the critical thinking skills and habits, and tries to develop the way for acquisition of critical thinking from the history of science.
2019, 34(7): 117-124
doi: 10.3866/PKU.DXHX201901031
Abstract:
In most cases, borylenes containing boron (I) are unstable. In this article, we proceed from the electron configuration of borylene and review the common methods of stabilizing this category of compounds through a series of borylenes in literature. In addition, the article briefly introduces the metallic borylenes and non-metallic borylenes and their properties. Some of these properties have been applied in nitrogen fixation.
In most cases, borylenes containing boron (I) are unstable. In this article, we proceed from the electron configuration of borylene and review the common methods of stabilizing this category of compounds through a series of borylenes in literature. In addition, the article briefly introduces the metallic borylenes and non-metallic borylenes and their properties. Some of these properties have been applied in nitrogen fixation.
