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2016 Volume 31 Issue 11
2016, 31(11): 1-10
doi: 10.3866/PKU.DXHX201607001
Abstract:
Recently,magnetic nanomaterials are widely applied in biomedical area owing to their unique physical and chemical properties.Herein,we introduce the progress of application of magnetic nanomaterials in cell separation,especially,in detection of circulating tumor cells from human whole blood.
Recently,magnetic nanomaterials are widely applied in biomedical area owing to their unique physical and chemical properties.Herein,we introduce the progress of application of magnetic nanomaterials in cell separation,especially,in detection of circulating tumor cells from human whole blood.
2016, 31(11): 11-18
doi: 10.3866/PKU.DXHX201609036
Abstract:
“Teaching-Practice-Test” Teaching Mode of Inorganic and Analytical Chemistry for Non-Chemical Majors
2016, 31(11): 19-21
doi: 10.3866/PKU.DXHX201604001
Abstract:
This article discussed "teaching-practice-test" teaching mode with teaching practical experience and content matching.Results showed that this mode highlighted the proportion of practice and problem-solving in the process of learning;improved students' ability to solve problems using professional and disciplinary knowledge;changed learning styles from cramming way to autonomous learning step by step and trained students' creativity.
This article discussed "teaching-practice-test" teaching mode with teaching practical experience and content matching.Results showed that this mode highlighted the proportion of practice and problem-solving in the process of learning;improved students' ability to solve problems using professional and disciplinary knowledge;changed learning styles from cramming way to autonomous learning step by step and trained students' creativity.
2016, 31(11): 22-27
doi: 10.3866/PKU.DXHX201603017
Abstract:
In this paper,the strategy to cultivate students' space sense ability was introduced in teaching of structure,reaction mechanism and rapid conformational transition equilibrium.Teaching practice showed that the strategy performance had a good effect.
In this paper,the strategy to cultivate students' space sense ability was introduced in teaching of structure,reaction mechanism and rapid conformational transition equilibrium.Teaching practice showed that the strategy performance had a good effect.
2016, 31(11): 28-36
doi: 10.3866/PKU.DXHX201604015
Abstract:
Based on the scientific nature of the teaching content and curriculum design,this article demonstrates that the chapter "atomic structure" in basic inorganic chemistry course should be divided into two chapters, "atom and atomic structure" and "element and the periodic law".The chapter "atom and atomic structure" includes the contents of atomic structure,electron motion state and the nucleus structure,while the chapter "element and the periodic law" includes the origin of elements,the establishment of the periodic law and basic property regularity of elements.Through teaching practice,such treatment is helpful in exploring the effect of the teaching content structure,and is agreeable with the law of epistemology.The reform of the teaching is helpful in improving students' scientific research consciousness in fundamental course teaching.
Based on the scientific nature of the teaching content and curriculum design,this article demonstrates that the chapter "atomic structure" in basic inorganic chemistry course should be divided into two chapters, "atom and atomic structure" and "element and the periodic law".The chapter "atom and atomic structure" includes the contents of atomic structure,electron motion state and the nucleus structure,while the chapter "element and the periodic law" includes the origin of elements,the establishment of the periodic law and basic property regularity of elements.Through teaching practice,such treatment is helpful in exploring the effect of the teaching content structure,and is agreeable with the law of epistemology.The reform of the teaching is helpful in improving students' scientific research consciousness in fundamental course teaching.
2016, 31(11): 37-44
doi: 10.3866/PKU.DXHX201603022
Abstract:
The determination of the absolute configuration (AC) of chiral compounds,especially the new chiral compounds,is one of the difficulties of the structure determination.The most widely used AC determination chiroptical spectroscopic methods include electronic and vibrational circular dichroism,optical rotatory dispersion,Raman optical activity etc.This mini review summarizes the main test principles,applications and corresponding theoretical calculation methods.With the developments of theoretical chemistry,the AC determination through instrumental characterization technique coupled with quantum chemical calculation,is envisaged to be the new trends of AC assignment.
The determination of the absolute configuration (AC) of chiral compounds,especially the new chiral compounds,is one of the difficulties of the structure determination.The most widely used AC determination chiroptical spectroscopic methods include electronic and vibrational circular dichroism,optical rotatory dispersion,Raman optical activity etc.This mini review summarizes the main test principles,applications and corresponding theoretical calculation methods.With the developments of theoretical chemistry,the AC determination through instrumental characterization technique coupled with quantum chemical calculation,is envisaged to be the new trends of AC assignment.
2016, 31(11): 45-50
doi: 10.3866/PKU.DXHX201602004
Abstract:
By starting from the origin of the concept of Hard-Soft-Acid-Base (HSAB),we briefly introduced the background of its establishment and development,and discussed about potential applications.Finally we gave a summary and evaluation based on the current knowledge and applications of HSAB.
By starting from the origin of the concept of Hard-Soft-Acid-Base (HSAB),we briefly introduced the background of its establishment and development,and discussed about potential applications.Finally we gave a summary and evaluation based on the current knowledge and applications of HSAB.
2016, 31(11): 51-55
doi: 10.3866/PKU.DXHX201603024
Abstract:
Through improving the way of isolating reactant in the eudiometry,the improved eudiometry is applied to quantitative determination,and the results are compared with that by other methods.The results show that the improved eudiometry is convenient,simple,fast and environmentally friendly,and can be applied to determine constants and quantitative analyses which involve quantitative generation of the gaseous product.
Through improving the way of isolating reactant in the eudiometry,the improved eudiometry is applied to quantitative determination,and the results are compared with that by other methods.The results show that the improved eudiometry is convenient,simple,fast and environmentally friendly,and can be applied to determine constants and quantitative analyses which involve quantitative generation of the gaseous product.
2016, 31(11): 56-60
doi: 10.3866/PKU.DXHX201603018
Abstract:
The separation experiment project introduced in this paper had been used in undergraduate teaching since the spring of 2015.A patented spiral wound diffusion dialysis membrane module was used to design a set of teaching instrument.Parts of an onging National Natural Science Foundation research contents were applied in teaching.The chemical engineering laboratory teaching contents were continuously enriched by following the forefront of scientific research.
The separation experiment project introduced in this paper had been used in undergraduate teaching since the spring of 2015.A patented spiral wound diffusion dialysis membrane module was used to design a set of teaching instrument.Parts of an onging National Natural Science Foundation research contents were applied in teaching.The chemical engineering laboratory teaching contents were continuously enriched by following the forefront of scientific research.
2016, 31(11): 61-66
doi: 10.3866/PKU.DXHX201603025
Abstract:
This experiment adopts electrospinning to prepare the PAN/PMMA gel polymer electrolyte membrane.The conductivity under different temperature was tested by AC impedance.The impact of temperature on the ion transport properties of composite gel polymer electrolyte membrane was explored.The prepared membrane was also compared with PAN/PMMA flat synovial membrane made by solvent casting method.The conductive kinetics of the two different forms of membranes was analyzed.The relationship between their conductive mechanism and microstructure was explored.The results showed that the conductive mechanism of the two kinds of membranes conforms to the Arrhenius formula,with the membrane made by electrostatic spinning having lower ion conductive activation energy.
This experiment adopts electrospinning to prepare the PAN/PMMA gel polymer electrolyte membrane.The conductivity under different temperature was tested by AC impedance.The impact of temperature on the ion transport properties of composite gel polymer electrolyte membrane was explored.The prepared membrane was also compared with PAN/PMMA flat synovial membrane made by solvent casting method.The conductive kinetics of the two different forms of membranes was analyzed.The relationship between their conductive mechanism and microstructure was explored.The results showed that the conductive mechanism of the two kinds of membranes conforms to the Arrhenius formula,with the membrane made by electrostatic spinning having lower ion conductive activation energy.
2016, 31(11): 67-71
doi: 10.3866/PKU.DXHX201604008
Abstract:
The preparation of benzoic acid through the oxidation of toluene by KMnO4 was improved upon microwave irradiation in the presence of benzyl triethylammonium chloride.The reaction conditions such as microwave power,reaction temperature,reaction time,the molar ratio of reactants,and the dosage of catalyst were investigated.The results showed that the optimal reaction conditions were as follows:irradiation time 40 min,microwave power 80 W,reaction temperature 80℃,0.2 equivalent of catalyst for toluene,and the molar ratio of KMnO4 to toluene to be 4.5:1.Compared with the traditional heating method,the microwave radiation shortened reaction time,and improved reaction efficiency up to 72.5% yield.Additionally,the preparation of benzoic acid was taken as an example to illustrate the application of the new method,namely, "teaching one,practicing two,and testing three" in organic chemistry laboratory course.
The preparation of benzoic acid through the oxidation of toluene by KMnO4 was improved upon microwave irradiation in the presence of benzyl triethylammonium chloride.The reaction conditions such as microwave power,reaction temperature,reaction time,the molar ratio of reactants,and the dosage of catalyst were investigated.The results showed that the optimal reaction conditions were as follows:irradiation time 40 min,microwave power 80 W,reaction temperature 80℃,0.2 equivalent of catalyst for toluene,and the molar ratio of KMnO4 to toluene to be 4.5:1.Compared with the traditional heating method,the microwave radiation shortened reaction time,and improved reaction efficiency up to 72.5% yield.Additionally,the preparation of benzoic acid was taken as an example to illustrate the application of the new method,namely, "teaching one,practicing two,and testing three" in organic chemistry laboratory course.
2016, 31(11): 72-75
doi: 10.3866/PKU.DXHX201603001
Abstract:
The treatment,recovery and detection of copper-containing waste from chemical laboratory were designed as a comprehensive experiment for college students.The students' ability of integrating theory with practice was enhanced.The environmental awareness was cultivated.At the same time,feasible suggestions for reducing laboratorial waste were proposed to strengthen the university chemistry laboratory waste pollution control.We aim to promote the teaching reform of chemistry experiment course,and to protect the environment.
The treatment,recovery and detection of copper-containing waste from chemical laboratory were designed as a comprehensive experiment for college students.The students' ability of integrating theory with practice was enhanced.The environmental awareness was cultivated.At the same time,feasible suggestions for reducing laboratorial waste were proposed to strengthen the university chemistry laboratory waste pollution control.We aim to promote the teaching reform of chemistry experiment course,and to protect the environment.
2016, 31(11): 76-80
doi: 10.3866/PKU.DXHX201603005
Abstract:
Point group in crystallography is one of the important subjects in structural chemistry.Some topics are very difficult to understand.To name a few,why does point group of D2d belong to tetragonal? Why are D4d and D6d not included in 32 kinds of crystallographic point groups? The two questions are easy to answer if we understand the following topic:for the Dnd point group,when n is odd,it contains an In symmetry axis;when n is even,it contains an I2n symmetry axis.In this work,graphic method and matrix method are adopted to clarify why the Dnd point group includes an S2n axis,and thus give explanations that D2d belongs to tetragonal as well as D4d and D6d are not included in 32 kinds of crystallographic point groups.
Point group in crystallography is one of the important subjects in structural chemistry.Some topics are very difficult to understand.To name a few,why does point group of D2d belong to tetragonal? Why are D4d and D6d not included in 32 kinds of crystallographic point groups? The two questions are easy to answer if we understand the following topic:for the Dnd point group,when n is odd,it contains an In symmetry axis;when n is even,it contains an I2n symmetry axis.In this work,graphic method and matrix method are adopted to clarify why the Dnd point group includes an S2n axis,and thus give explanations that D2d belongs to tetragonal as well as D4d and D6d are not included in 32 kinds of crystallographic point groups.
2016, 31(11): 81-82
doi: 10.3866/PKU.DXHX201603019
Abstract:
The luminescence mechanism of anti stokes light is explained in this paper.According to the definition of fluorescence,it is concluded that the anti stokes fluorescence does not belong to fluorescence.This paper points out the conceptual mistakes in the teaching materials of instrumental analysis,and briefly analyzes the causes of the mistakes.
The luminescence mechanism of anti stokes light is explained in this paper.According to the definition of fluorescence,it is concluded that the anti stokes fluorescence does not belong to fluorescence.This paper points out the conceptual mistakes in the teaching materials of instrumental analysis,and briefly analyzes the causes of the mistakes.
2016, 31(11): 83-88
doi: 10.3866/PKU.DXHX201604031
Abstract:
The two main reported approaches for deducing the capillary rise equation were summarized.The simplification principle and the assumption for force analysis approach were explained.By taking the hydrodynamics,the flow rate and the height of liquid in capillary were further discussed.For liquid rise in square capillary,three situations were analyzed with some important conclusions reached.
The two main reported approaches for deducing the capillary rise equation were summarized.The simplification principle and the assumption for force analysis approach were explained.By taking the hydrodynamics,the flow rate and the height of liquid in capillary were further discussed.For liquid rise in square capillary,three situations were analyzed with some important conclusions reached.
2016, 31(11): 89-92
doi: 10.3866/PKU.DXHX201603004
Abstract:
This paper presents a novel method for finding the pH of a solution containing a weak polyprotic acid (or base).The new method has the following characteristics:its constraint condition is simple,namely if a term is less than 5% of the maximum term among the polynomial,its contribution can be ignored.The calculation steps are clear and normalized.The universality of the new method is good,applicable to the pH calculation for both weak polyprotic acids and weak polyprotic bases.
This paper presents a novel method for finding the pH of a solution containing a weak polyprotic acid (or base).The new method has the following characteristics:its constraint condition is simple,namely if a term is less than 5% of the maximum term among the polynomial,its contribution can be ignored.The calculation steps are clear and normalized.The universality of the new method is good,applicable to the pH calculation for both weak polyprotic acids and weak polyprotic bases.
2016, 31(11): 93-96
doi: 10.3866/PKU.DXHX201603041
Abstract:
This paper introduced three kinds of chiral xyliphos complexes and the according nomenclatures.Then inappropriate nomenclatures and expression of configuration on chiral xyliphos complexes in some literatures were pointed out and corrected.Finally,some typical examples were used to enhance the command of nomenclature of organics.
This paper introduced three kinds of chiral xyliphos complexes and the according nomenclatures.Then inappropriate nomenclatures and expression of configuration on chiral xyliphos complexes in some literatures were pointed out and corrected.Finally,some typical examples were used to enhance the command of nomenclature of organics.
2016, 31(11): 97-100
doi: 10.3866/PKU.DXHX201603023
Abstract:
A two-parameter data fitting method for classical surface tension experiment with Origin software was introduced.The method is not only more rigorous,but also easier for study and use;thus it is suitable for innovation of chemistry laboratory and computer aided design (CAD) teaching.
A two-parameter data fitting method for classical surface tension experiment with Origin software was introduced.The method is not only more rigorous,but also easier for study and use;thus it is suitable for innovation of chemistry laboratory and computer aided design (CAD) teaching.
2016, 31(11): 101-110
doi: 10.3866/PKU.DXHX201608024
Abstract:
2016, 31(11): 111-117
doi: 10.3866/PKU.DXHX201609016
Abstract:
This paper summarizes the 10th National Undergraduate Chemistry Laboratory Tournament,analyzes the problems existing in current experiment teaching which are reflected in the tournament,and gives some reform suggestions on the basic contents of experiment teaching and the standardization of experiment operation.
This paper summarizes the 10th National Undergraduate Chemistry Laboratory Tournament,analyzes the problems existing in current experiment teaching which are reflected in the tournament,and gives some reform suggestions on the basic contents of experiment teaching and the standardization of experiment operation.
2016, 31(11): 118-119
doi: 10.3866/PKU.DXHX201609037
Abstract:
2016, 31(11): 120-121
doi: 10.3866/PKU.DXHX201609038
Abstract:
2016, 31(11): 122-122
doi: 10.3866/PKU.DXHX201609039
Abstract:
