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2016 Volume 31 Issue 7
2016, 31(7): 1-13
doi: 10.3866/PKU.DXHX201512007
Abstract:
In this paper, the Gd(Ⅲ)-based contrast agents are reviewed from four aspects as followed:principles, conditions, research progresses and approaches for improving relaxivity. The research progresses in the fields of fluorescent and biological contrast agents are deeply introduced. Moreover, the activity of enzyme, pH and metal ions of biological contrast agents are discussed.
In this paper, the Gd(Ⅲ)-based contrast agents are reviewed from four aspects as followed:principles, conditions, research progresses and approaches for improving relaxivity. The research progresses in the fields of fluorescent and biological contrast agents are deeply introduced. Moreover, the activity of enzyme, pH and metal ions of biological contrast agents are discussed.
2016, 31(7): 14-19
doi: 10.3866/PKU.DXHX201606018
Abstract:
2016, 31(7): 20-23
doi: 10.3866/PKU.DXHX201509013
Abstract:
In this article, the topic of "chemical principles in warmer pad" is used as an example to illustrate how problem-based learning (PBL) and case learning (CL) are used in the teaching of general chemistry. We take the advantages of PBL to arouse the studying interests of students in the casing learning atmosphere. Moreover, the teacher leads the discussion. By using these two teaching methods properly, students' active learning ability, the skills of analyzing and solving problems, as well as the comprehensive practical ability can be improved.
In this article, the topic of "chemical principles in warmer pad" is used as an example to illustrate how problem-based learning (PBL) and case learning (CL) are used in the teaching of general chemistry. We take the advantages of PBL to arouse the studying interests of students in the casing learning atmosphere. Moreover, the teacher leads the discussion. By using these two teaching methods properly, students' active learning ability, the skills of analyzing and solving problems, as well as the comprehensive practical ability can be improved.
2016, 31(7): 24-28
doi: 10.3866/PKU.DXHX201507019
Abstract:
The experiment teaching mode of inorganic and analytical chemistry was constructed for training applied innovative talents. The specific implementation measures of this mode were proposed, with the expected results prospected. Problems needed to be solved were also pointed out. The teaching mode advocates the primary classroom teaching combined with the participation of company and society, where the "learning-production" and "learning-research" will be formed. Students are encouraged to get involved in the practical production, social service and scientific research. In such a way, their abilities of innovation and social adaptation will be improved.
The experiment teaching mode of inorganic and analytical chemistry was constructed for training applied innovative talents. The specific implementation measures of this mode were proposed, with the expected results prospected. Problems needed to be solved were also pointed out. The teaching mode advocates the primary classroom teaching combined with the participation of company and society, where the "learning-production" and "learning-research" will be formed. Students are encouraged to get involved in the practical production, social service and scientific research. In such a way, their abilities of innovation and social adaptation will be improved.
2016, 31(7): 29-33
doi: 10.3866/PKU.DXHX201509016
Abstract:
Based on the reform of the basic chemistry courses system and teaching contents in agricultural and forestry universities, a distinctive multilevel agricultural-based curriculum system was built in which optimally-designed teaching contents, enhanced teaching pertinence, and the highlighted personality developments of students have laid an important chemical foundation for cultivating innovative talents of agricultural colleges.
Based on the reform of the basic chemistry courses system and teaching contents in agricultural and forestry universities, a distinctive multilevel agricultural-based curriculum system was built in which optimally-designed teaching contents, enhanced teaching pertinence, and the highlighted personality developments of students have laid an important chemical foundation for cultivating innovative talents of agricultural colleges.
2016, 31(7): 34-38
doi: 10.3866/PKU.DXHX201507009
Abstract:
This article discusses about the application of constructivism teaching theory in inorganic and analytical chemistry teaching based on the characteristics of inorganic and analytical chemistry course. The teaching mode, independence of students and teaching quality are improved in this way.
This article discusses about the application of constructivism teaching theory in inorganic and analytical chemistry teaching based on the characteristics of inorganic and analytical chemistry course. The teaching mode, independence of students and teaching quality are improved in this way.
2016, 31(7): 39-43
doi: 10.3866/PKU.DXHX201508012
Abstract:
The theory of Karpicker retrieval practice is applied in the inorganic chemistry course teaching in order to improve the effect of classroom teaching of inorganic chemistry. The strategy is designed in particular for chemistry majoring undergraduates with less learning interests and poor initiatives and passions, as well as unpleasant teaching quality of professional course. Through three years of chemistry teaching practices of the theory of Karpicker retrieval practice, the results demonstrated that retrieval practice not only contributed to information encoding and information retrieve, but also improved learning results of chemical undergraduates significantly.
The theory of Karpicker retrieval practice is applied in the inorganic chemistry course teaching in order to improve the effect of classroom teaching of inorganic chemistry. The strategy is designed in particular for chemistry majoring undergraduates with less learning interests and poor initiatives and passions, as well as unpleasant teaching quality of professional course. Through three years of chemistry teaching practices of the theory of Karpicker retrieval practice, the results demonstrated that retrieval practice not only contributed to information encoding and information retrieve, but also improved learning results of chemical undergraduates significantly.
2016, 31(7): 44-48
doi: 10.3866/PKU.DXHX201511028
Abstract:
We conducted a survey using questionnaire to the laboratory condition, curriculum setting and teaching model, in order to examine the effect of minority students' basic chemistry experiments at Tarim University. The results demonstrate that the whole experiment teaching effect is satisfactory, but instead there is still shortage on developing students' ability of seeking knowledge and solving the problem on their own. This article discussed the problem existing in basic chemistry experiment teaching and put forward measures, considering the characteristics of minority students.
We conducted a survey using questionnaire to the laboratory condition, curriculum setting and teaching model, in order to examine the effect of minority students' basic chemistry experiments at Tarim University. The results demonstrate that the whole experiment teaching effect is satisfactory, but instead there is still shortage on developing students' ability of seeking knowledge and solving the problem on their own. This article discussed the problem existing in basic chemistry experiment teaching and put forward measures, considering the characteristics of minority students.
2016, 31(7): 49-51
doi: 10.3866/PKU.DXHX201507010
Abstract:
In this paper, the implementation of research-oriented teaching mode in coordination chemistry was introduced, including the strategies, main contents and evaluation.
In this paper, the implementation of research-oriented teaching mode in coordination chemistry was introduced, including the strategies, main contents and evaluation.
2016, 31(7): 52-56
doi: 10.3866/PKU.DXHX201507020
Abstract:
In the teaching of instrumental analysis for students majored in chemical engineering and technology, environmental science, chemical and pharmaceutical engineering, chemistry and applied chemistry, emphases have to be made according to the specialty and the future career. With the rational positioning for training applied talents and innovative talents, the new course system was established by selecting course contents for specific major needs led by the main line of the teaching. Diversified teaching approaches as well as advanced instrumental analysis experiments are also adopted for training talents.
In the teaching of instrumental analysis for students majored in chemical engineering and technology, environmental science, chemical and pharmaceutical engineering, chemistry and applied chemistry, emphases have to be made according to the specialty and the future career. With the rational positioning for training applied talents and innovative talents, the new course system was established by selecting course contents for specific major needs led by the main line of the teaching. Diversified teaching approaches as well as advanced instrumental analysis experiments are also adopted for training talents.
2016, 31(7): 57-60
doi: 10.3866/PKU.DXHX201509006
Abstract:
Fine chemicals field has become a hot issue in the world chemical market. For chemical professionals who are engaged in new products development, the compound technology is one of the rulers that reflects their skill level. The fine chemical formula design course is educational for students majoring in chemistry and chemical engineering for their vocational skills. This article introduces the college textbook entitled Fine Chemical Formula Design and published by Chemical Industry Publishing House, as well as recommends the new test forms and requirements in the teaching process.
Fine chemicals field has become a hot issue in the world chemical market. For chemical professionals who are engaged in new products development, the compound technology is one of the rulers that reflects their skill level. The fine chemical formula design course is educational for students majoring in chemistry and chemical engineering for their vocational skills. This article introduces the college textbook entitled Fine Chemical Formula Design and published by Chemical Industry Publishing House, as well as recommends the new test forms and requirements in the teaching process.
2016, 31(7): 61-64
doi: 10.3866/PKU.DXHX201509014
Abstract:
Seminar of quality assurance of analytical test was designed and implemented in the course of analytical chemistry for undergraduates of grade 2012, 2013 and 2014. Class reports, questionnaires, and summary reports on seminar of quality assurance of analytical test were conducted to evaluate the teaching outcomes. The results displayed that the seminar teaching method was helpful in improving students' abilities of independent study, analyzing and solving the problems, and logical thinking, as well as improving the teaching quality.
Seminar of quality assurance of analytical test was designed and implemented in the course of analytical chemistry for undergraduates of grade 2012, 2013 and 2014. Class reports, questionnaires, and summary reports on seminar of quality assurance of analytical test were conducted to evaluate the teaching outcomes. The results displayed that the seminar teaching method was helpful in improving students' abilities of independent study, analyzing and solving the problems, and logical thinking, as well as improving the teaching quality.
2016, 31(7): 65-71
doi: 10.3866/PKU.DXHX201509019
Abstract:
Eu(Ⅲ) acetate and Tb(Ⅲ) acetate reacted with acetyl acetone at about 60℃ to synthesize two different rare earth β-diketone complexes. With the UV light illumination, the fluorescence of Eu(acac)3·3H2O is dark red, while the Tb(acac)3·3H2O is bright green. Results from infrared spectra agreed with the theoretical prediction. Through fluorescence analysis, we found these complexes are relatively better luminescent materials. These complexes presented good luminescent properties and thermal stability.
Eu(Ⅲ) acetate and Tb(Ⅲ) acetate reacted with acetyl acetone at about 60℃ to synthesize two different rare earth β-diketone complexes. With the UV light illumination, the fluorescence of Eu(acac)3·3H2O is dark red, while the Tb(acac)3·3H2O is bright green. Results from infrared spectra agreed with the theoretical prediction. Through fluorescence analysis, we found these complexes are relatively better luminescent materials. These complexes presented good luminescent properties and thermal stability.
2016, 31(7): 72-76
doi: 10.3866/PKU.DXHX201508009
Abstract:
Potassium tris(oxalato) ferrate(Ⅲ) trihydrate has the industrial production value, and its synthesis is a classic experiment in the laboratory course for chemistry majors. However, results from the experimental procedure in the textbook are unsatisfactory. Based on the rigorous analysis of chemical equilibrium theory, we first proposed that the key factor for improving the yield is to strictly control the amount of oxalic acid and potassium oxalate. The improved synthesis conditions are as follows:in the oxidation step, the reaction is carried out at 40℃, and the concentration of H2O2 is 6%; after full oxidation, the solution is kept boiling for two minutes; a slight excess of oxalic acid and 10% excess of potassium oxalate are used in the acid dissolution step; sufficiently cooling is followed in crystallization. With the improved procedure, operations are simplified and raw materials are saved. The yield is 87% for laboratory average and greater than 70% for students in the laboratory class.
Potassium tris(oxalato) ferrate(Ⅲ) trihydrate has the industrial production value, and its synthesis is a classic experiment in the laboratory course for chemistry majors. However, results from the experimental procedure in the textbook are unsatisfactory. Based on the rigorous analysis of chemical equilibrium theory, we first proposed that the key factor for improving the yield is to strictly control the amount of oxalic acid and potassium oxalate. The improved synthesis conditions are as follows:in the oxidation step, the reaction is carried out at 40℃, and the concentration of H2O2 is 6%; after full oxidation, the solution is kept boiling for two minutes; a slight excess of oxalic acid and 10% excess of potassium oxalate are used in the acid dissolution step; sufficiently cooling is followed in crystallization. With the improved procedure, operations are simplified and raw materials are saved. The yield is 87% for laboratory average and greater than 70% for students in the laboratory class.
2016, 31(7): 77-79
doi: 10.3866/PKU.DXHX201508014
Abstract:
le Chatelier principle is empirical and qualitative. In fact, it often comes to incorrect results about the shift direction to restore chemical equilibrium, since introduced in 1884. It is proved theoretically that le Chatelier principle's application conditions are very strict. The modern chemical equilibrium principle is quantitative and legible, and has been taught widely. We propose that le Chatelier principle should not be used in chemical teaching anymore.
le Chatelier principle is empirical and qualitative. In fact, it often comes to incorrect results about the shift direction to restore chemical equilibrium, since introduced in 1884. It is proved theoretically that le Chatelier principle's application conditions are very strict. The modern chemical equilibrium principle is quantitative and legible, and has been taught widely. We propose that le Chatelier principle should not be used in chemical teaching anymore.
2016, 31(7): 80-82
doi: 10.3866/PKU.DXHX201509005
Abstract:
A generalized thermodynamic equation is presented in this paper.
A generalized thermodynamic equation is presented in this paper.
2016, 31(7): 83-90
doi: 10.3866/PKU.DXHX201509017
Abstract:
Current criteria for spontaneity are used with the confined conditions. The various definitions of spontaneous change show the lack of universality. Here, the first law of thermodynamics was put in the total entropy criterion without any constraints. Then another form of entropy criterion was obtained and discussed. The nature of energy change in thermodynamics processes was summarized based on the characteristics of spontaneous process. As a result, the universal definition of spontaneous process was put forward. The original total entropy criterion can distinguish between the reversible and irreversible processes, but not the spontaneous and non-spontaneous processes. Another form of the entropy criterion, i.e., the exergy criterion for the arbitrary process in the closed system, was proposed. This criterion can distinguish between the spontaneous and non-spontaneous processes. Through the theoretical derivation and the actual examples, we found that the exergy criterion is equivalent to the total entropy criterion. The exergy criterion can be returned to all kinds of direction criteria when using the corresponding limited conditions. In the paper, the spontaneity criteria for the processes with variable temperature or pressure were also given, which have not appeared in the current textbooks. In summary, the universal definition and the exergy criterion can solve the problems arisen from the confusing conception and explanation related to spontaneous processes.
Current criteria for spontaneity are used with the confined conditions. The various definitions of spontaneous change show the lack of universality. Here, the first law of thermodynamics was put in the total entropy criterion without any constraints. Then another form of entropy criterion was obtained and discussed. The nature of energy change in thermodynamics processes was summarized based on the characteristics of spontaneous process. As a result, the universal definition of spontaneous process was put forward. The original total entropy criterion can distinguish between the reversible and irreversible processes, but not the spontaneous and non-spontaneous processes. Another form of the entropy criterion, i.e., the exergy criterion for the arbitrary process in the closed system, was proposed. This criterion can distinguish between the spontaneous and non-spontaneous processes. Through the theoretical derivation and the actual examples, we found that the exergy criterion is equivalent to the total entropy criterion. The exergy criterion can be returned to all kinds of direction criteria when using the corresponding limited conditions. In the paper, the spontaneity criteria for the processes with variable temperature or pressure were also given, which have not appeared in the current textbooks. In summary, the universal definition and the exergy criterion can solve the problems arisen from the confusing conception and explanation related to spontaneous processes.
2016, 31(7): 91-95
doi: 10.3866/PKU.DXHX201509011
Abstract:
In this paper, we represent the structures of many-electron atoms with different approximate Hamiltonian operators. Some related contents such as Slater determinants, electronic configurations, terms and levels are also discussed.
In this paper, we represent the structures of many-electron atoms with different approximate Hamiltonian operators. Some related contents such as Slater determinants, electronic configurations, terms and levels are also discussed.
2016, 31(7): 96-100
doi: 10.3866/PKU.DXHX201508010
Abstract:
In an ideal completely miscible two components liquid system, the two components strictly abide by the Raoult's law, and their plane phase diagrams have a definite function relationship. Based on the Clausius-Clapeyron equation, the functional analytic formula ofp-x、T-x and p-T phase diagrams in this ideal system were derived in the present paper.
In an ideal completely miscible two components liquid system, the two components strictly abide by the Raoult's law, and their plane phase diagrams have a definite function relationship. Based on the Clausius-Clapeyron equation, the functional analytic formula ofp-x、T-x and p-T phase diagrams in this ideal system were derived in the present paper.
2016, 31(7): 101-106
doi: 10.3866/PKU.DXHX201509009
Abstract:
In this paper, it is found that the chemistry specialty in Australian National University has distinctive features in the school system, curriculum, teaching mode, teaching content and examination mode based on the investigation to Australian National University. By comparison with the Australian chemistry education teaching mode, we hope that the diversity can bring some revelation to our teaching reform.
In this paper, it is found that the chemistry specialty in Australian National University has distinctive features in the school system, curriculum, teaching mode, teaching content and examination mode based on the investigation to Australian National University. By comparison with the Australian chemistry education teaching mode, we hope that the diversity can bring some revelation to our teaching reform.
