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2019 Volume 34 Issue 2
2019, 34(2): 1-16
doi: 10.3866/PKU.DXHX201806019
Abstract:
In recent decades, hypervalent iodine chemistry has witnessed its explosive development. Hypervalent iodine reagents have drawn considerable attentions and their reactivities have been continuously explored. Hypervalent iodine reagents, featuring facile availability and easy handling, offer multiple advantages over established methods as a green, efficient and multipurpose oxidant. The reactivities of hypervalent iodine reagents are similar to derivatives of mercury, chromium, lead, thallium and other heavy metals, but the toxicity and environmental problems are less than those of the heavy metal reagents. This paper mainly introduces the development of hypervalent iodine chemistry, the structure and classification of hypervalent iodine reagents and the synthetic application of hypervalent iodine reagents in organic chemistry, materials chemistry and industrial synthesis.
In recent decades, hypervalent iodine chemistry has witnessed its explosive development. Hypervalent iodine reagents have drawn considerable attentions and their reactivities have been continuously explored. Hypervalent iodine reagents, featuring facile availability and easy handling, offer multiple advantages over established methods as a green, efficient and multipurpose oxidant. The reactivities of hypervalent iodine reagents are similar to derivatives of mercury, chromium, lead, thallium and other heavy metals, but the toxicity and environmental problems are less than those of the heavy metal reagents. This paper mainly introduces the development of hypervalent iodine chemistry, the structure and classification of hypervalent iodine reagents and the synthetic application of hypervalent iodine reagents in organic chemistry, materials chemistry and industrial synthesis.
2019, 34(2): 17-21
doi: 10.3866/PKU.DXHX201806007
Abstract:
The practice and innovation ability of professional masters are the important goal during the professional master training process. In this paper, the practice course of “chemical power manufacturing engineering” in Harbin Institute of Technology has been used as an example to resolve the problems of the course. The teaching reform has been carried out on the reformation in the aspects of teaching methods, teaching contents, teaching staff, and evaluation system. Finally, we construct the autonomous learning system of students both in the class and out of class, and discuss about how to improve the abilities of practice, innovation, and scientific research of professional masters.
The practice and innovation ability of professional masters are the important goal during the professional master training process. In this paper, the practice course of “chemical power manufacturing engineering” in Harbin Institute of Technology has been used as an example to resolve the problems of the course. The teaching reform has been carried out on the reformation in the aspects of teaching methods, teaching contents, teaching staff, and evaluation system. Finally, we construct the autonomous learning system of students both in the class and out of class, and discuss about how to improve the abilities of practice, innovation, and scientific research of professional masters.
2019, 34(2): 22-25
doi: 10.3866/PKU.DXHX201807008
Abstract:
With the development modes of chemical industries in China being transformed from the simple capacity-expansion to comprehensive connotative development of manufacture, quality control, market and environmental protection, the importance for undergraduates to master relevant knowledge of chemical business management is rising. This paper introduced the necessity and feasibility for introducing chemical business management related projects into graduation thesis of students of applied chemistry major, which will provide a new way to improve the quality of graduation thesis.
With the development modes of chemical industries in China being transformed from the simple capacity-expansion to comprehensive connotative development of manufacture, quality control, market and environmental protection, the importance for undergraduates to master relevant knowledge of chemical business management is rising. This paper introduced the necessity and feasibility for introducing chemical business management related projects into graduation thesis of students of applied chemistry major, which will provide a new way to improve the quality of graduation thesis.
2019, 34(2): 26-29
doi: 10.3866/PKU.DXHX201807019
Abstract:
We focused on strengthening the cultivation of students' teaching practice ability and innovation ability through a variety of initiatives such as the plan for improving teachers' educational ability and the plan for enhancing scientific innovation ability. Some methods, such as combining studying professional knowledges with capability of innovation for scientific research, and teaching skill training with middle school teaching, were developed. These methods have obviously improved the students' ability of innovation and teaching skills.
We focused on strengthening the cultivation of students' teaching practice ability and innovation ability through a variety of initiatives such as the plan for improving teachers' educational ability and the plan for enhancing scientific innovation ability. Some methods, such as combining studying professional knowledges with capability of innovation for scientific research, and teaching skill training with middle school teaching, were developed. These methods have obviously improved the students' ability of innovation and teaching skills.
2019, 34(2): 30-36
doi: 10.3866/PKU.DXHX201806020
Abstract:
X-ray crystallography is the study of the structures of crystallized materials. X-ray diffraction analysis is the most important technology to measure and provide the more detailed structural information. In this paper, the brief history of X-ray crystallography is introduced and its contribution to human civilization is included. The importance of X-ray crystallography in university education, particularly in general education, is discussed.
X-ray crystallography is the study of the structures of crystallized materials. X-ray diffraction analysis is the most important technology to measure and provide the more detailed structural information. In this paper, the brief history of X-ray crystallography is introduced and its contribution to human civilization is included. The importance of X-ray crystallography in university education, particularly in general education, is discussed.
2019, 34(2): 37-43
doi: 10.3866/PKU.DXHX201807006
Abstract:
It is one of the contents of the connotation construction of laboratory construction and management to complete the meticulous preparation of basic chemistry experiments scientifically and provide more efficient services for the laboratory teaching. This paper mainly introduces practices and experiences in the preparation of inorganic and chemical analysis laboratory teaching of National Demonstration Center for Experimental Chemistry Education (Xiamen University), hoping to provide applicable guidance for the preparation of basic chemistry laboratories.
It is one of the contents of the connotation construction of laboratory construction and management to complete the meticulous preparation of basic chemistry experiments scientifically and provide more efficient services for the laboratory teaching. This paper mainly introduces practices and experiences in the preparation of inorganic and chemical analysis laboratory teaching of National Demonstration Center for Experimental Chemistry Education (Xiamen University), hoping to provide applicable guidance for the preparation of basic chemistry laboratories.
2019, 34(2): 44-48
doi: 10.3866/PKU.DXHX201806012
Abstract:
We present three management modes to enhance the management to the medium-scale and small-scale instruments in basic chemistry laboratory, such as the whole-process management, classification management and internet plus auxiliary management. These methods make the management of the instrument scientific, efficient and standard, and improve the utilization rate and availability, and thus, improve the teaching quality of basic chemistry laboratory.
We present three management modes to enhance the management to the medium-scale and small-scale instruments in basic chemistry laboratory, such as the whole-process management, classification management and internet plus auxiliary management. These methods make the management of the instrument scientific, efficient and standard, and improve the utilization rate and availability, and thus, improve the teaching quality of basic chemistry laboratory.
2019, 34(2): 49-54
doi: 10.3866/PKU.DXHX201806014
Abstract:
The experiment on preparation and empirical formula determination of hexamine cobalt(Ⅲ) chloride is a comprehensive experiment in the basic chemistry laboratory. The coordination compound was prepared by the reaction of CoCl2 with H2O2 as the oxidant, excess ammonia and NH4Cl with the catalysis of activated carbon. The empirical formula of the product was obtained by taking the integer of the ratio of NH3, Co and Cl based on their contents from titration. In this paper, the titration method of Cl was improved. The Cl contents from the potentiometric titration method and Mohr method were compared. Results show that the potentiometric titration method has the advantages of higher precision, better reproducibility and reliability, as well as the better teaching effect.
The experiment on preparation and empirical formula determination of hexamine cobalt(Ⅲ) chloride is a comprehensive experiment in the basic chemistry laboratory. The coordination compound was prepared by the reaction of CoCl2 with H2O2 as the oxidant, excess ammonia and NH4Cl with the catalysis of activated carbon. The empirical formula of the product was obtained by taking the integer of the ratio of NH3, Co and Cl based on their contents from titration. In this paper, the titration method of Cl was improved. The Cl contents from the potentiometric titration method and Mohr method were compared. Results show that the potentiometric titration method has the advantages of higher precision, better reproducibility and reliability, as well as the better teaching effect.
2019, 34(2): 55-60
doi: 10.3866/PKU.DXHX201807046
Abstract:
Isothermal cycle is a classical method to solve thermodynamic problems in physical chemistry textbooks. In this paper, it is pointed out that The Gibbs free energy change of the reversible phase transformation of the droplet into the gas should be given by the criterion in the method. The Gibbs free energy criterion at constant temperature, gas and liquid pressures can be proven based on the basic principles of thermodynamics. At the same time, a new model and a new understanding of the isothermal cycle method are put forward, which is more straightforward, and thus suitable for teaching.
Isothermal cycle is a classical method to solve thermodynamic problems in physical chemistry textbooks. In this paper, it is pointed out that The Gibbs free energy change of the reversible phase transformation of the droplet into the gas should be given by the criterion in the method. The Gibbs free energy criterion at constant temperature, gas and liquid pressures can be proven based on the basic principles of thermodynamics. At the same time, a new model and a new understanding of the isothermal cycle method are put forward, which is more straightforward, and thus suitable for teaching.
2019, 34(2): 61-64
doi: 10.3866/PKU.DXHX201807040
Abstract:
Living polymerization, particularly the criteria of living polymerization, plays an important role in the course of polymer chemistry. In this paper, we summarize the criteria of living polymerization and analyze the sources of each criterion carefully. These teaching contents can be used as supplements to the existing textbooks, which help students understand the connotation and denotation of living polymerization deeply.
Living polymerization, particularly the criteria of living polymerization, plays an important role in the course of polymer chemistry. In this paper, we summarize the criteria of living polymerization and analyze the sources of each criterion carefully. These teaching contents can be used as supplements to the existing textbooks, which help students understand the connotation and denotation of living polymerization deeply.
2019, 34(2): 65-69
doi: 10.3866/PKU.DXHX201811004
Abstract:
Taking the chapter of electrolyte solution as an example, multiple kinds of treatments on the data listed in tables in physical chemistry textbook are introduced in this article. Data supplement, diagram with curves, data difference calculation and the corresponding integrated application have been used to analyze the corresponding topics, including the ionic mobility, transference number and mean activity factor of ions. Based on the treatments, active thinking and in-depth analysis from sensitive view can be achieved for the students, and the understanding about theoretical knowledge can be enhanced.
Taking the chapter of electrolyte solution as an example, multiple kinds of treatments on the data listed in tables in physical chemistry textbook are introduced in this article. Data supplement, diagram with curves, data difference calculation and the corresponding integrated application have been used to analyze the corresponding topics, including the ionic mobility, transference number and mean activity factor of ions. Based on the treatments, active thinking and in-depth analysis from sensitive view can be achieved for the students, and the understanding about theoretical knowledge can be enhanced.
2019, 34(2): 70-75
doi: 10.3866/PKU.DXHX201806033
Abstract:
Volumetric titration analysis is an important content of chemical analysis; but it is traditionally considered to use large amount sample, take long analysis time, have low sensitivity, and involve harsh analytical conditions. This paper provides perspectives for the above issues. Examples are introduced to illustrate that the sample amount can be easily reduced with improved sample throughput by the use of automatic titration analysis. The non-traditional end-point indication method improves the sensitivity with simplified analytical condition. We hope to introduce the different titration analysis and the breadth of applications to students, and thus, to stimulate their interest.
Volumetric titration analysis is an important content of chemical analysis; but it is traditionally considered to use large amount sample, take long analysis time, have low sensitivity, and involve harsh analytical conditions. This paper provides perspectives for the above issues. Examples are introduced to illustrate that the sample amount can be easily reduced with improved sample throughput by the use of automatic titration analysis. The non-traditional end-point indication method improves the sensitivity with simplified analytical condition. We hope to introduce the different titration analysis and the breadth of applications to students, and thus, to stimulate their interest.
2019, 34(2): 76-80
doi: 10.3866/PKU.DXHX201806015
Abstract:
The subjunctive mood plays an important role in expressing wishes, doubts and uncertainties. In this paper, we analyze and summarize the use of subjunctive mood in several examples selected from chemical literatures. It is proposed that attention should be paid to accurately understand the author's intention when subjunctive mood is used.
The subjunctive mood plays an important role in expressing wishes, doubts and uncertainties. In this paper, we analyze and summarize the use of subjunctive mood in several examples selected from chemical literatures. It is proposed that attention should be paid to accurately understand the author's intention when subjunctive mood is used.
2019, 34(2): 81-89
doi: 10.3866/PKU.DXHX201805027
Abstract:
The 21st century witnesses the most rapid development of life science and computer science. As the core of current scientific research, chemistry forms an integration in close combination with other subjects including biology and information science. With the appearance and development of various interdisciplinary subjects, integrating the methodology of computer science and organic chemistry is becoming one of the main trends to understand biomacromolecules and then to solve problems in life science. Therefore, it is also enterprising and necessary to introduce relative contents to fundamental biochemistry and chemical biology education. An organic experiment has been designed and carried out, right at the time point, for the undergraduate education with chemistry related majors based on a commonly used software named as “PyMOL”. The experiment allows students to study the three-dimensional structure of a typical enzyme and with their solid understanding of organic chemistry mechanisms to investigate how the enzyme can catalyze a specific reaction. As a combination of multiple fields as organic chemistry, biochemistry, bioinformatics, protein structural biology, etc., this experimental design can largely enhance the students' understanding of higher-order protein structures, which lays the foundation of the biochemistry education and research. This experiment kills two birds with one stone, since it can also greatly intrigue students in chemistry learning. This is important to train all the promising students of interdisciplinary majors to initiate their innovative study. It's worthy to be introduced to bioorganic experimental design in China.
The 21st century witnesses the most rapid development of life science and computer science. As the core of current scientific research, chemistry forms an integration in close combination with other subjects including biology and information science. With the appearance and development of various interdisciplinary subjects, integrating the methodology of computer science and organic chemistry is becoming one of the main trends to understand biomacromolecules and then to solve problems in life science. Therefore, it is also enterprising and necessary to introduce relative contents to fundamental biochemistry and chemical biology education. An organic experiment has been designed and carried out, right at the time point, for the undergraduate education with chemistry related majors based on a commonly used software named as “PyMOL”. The experiment allows students to study the three-dimensional structure of a typical enzyme and with their solid understanding of organic chemistry mechanisms to investigate how the enzyme can catalyze a specific reaction. As a combination of multiple fields as organic chemistry, biochemistry, bioinformatics, protein structural biology, etc., this experimental design can largely enhance the students' understanding of higher-order protein structures, which lays the foundation of the biochemistry education and research. This experiment kills two birds with one stone, since it can also greatly intrigue students in chemistry learning. This is important to train all the promising students of interdisciplinary majors to initiate their innovative study. It's worthy to be introduced to bioorganic experimental design in China.
2019, 34(2): 90-98
doi: 10.3866/PKU.DXHX2018110191
Abstract:
The problems in the preliminary test of the 32nd Chinese Chemistry Olympiad were resolved. The problem-solving techniques and calculations were developed, and the background and bibliography involved were also provided.
The problems in the preliminary test of the 32nd Chinese Chemistry Olympiad were resolved. The problem-solving techniques and calculations were developed, and the background and bibliography involved were also provided.
