• Clean Technology
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• v.2 no.2
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• pp.90-99
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• 1996

Being confronted with the 21th century at hand, a paradigm shift has been a common topic for development in many fields. Among these, a concept of sustainable development is the most important one to resolve conflict and nurture mutualism between science/technology(SCI/TEC) and society/environment(SOC/ENV). Looking briefly over the resent stats of the chemical industry in Japan, in this paper, we will introduce a research program named simple chemistry as an example for such a challenge.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2002.04a
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• pp.9-12
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• 2002

The Dyestuff is fixed to the fiber to color it in a unique way depending on the chemistry between them. Whenever there arose problems in coloring fibers, the chemistry of dyestuff could be adjusted to solve them. That manner new concept dye classes, e.g., reactive dyes, disperse dyes, cationic dyes, have arrived along with the introduction of new fibers. The attempt has made to introduce the new reactive dye to solve this problem.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1225-1230
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• 2012

A new unsymmetrical zinc phthalocyanine has been designed and synthesized based on the 'push-pull' and extended ${\pi}$-conjugation concept for the dye-sensitized solar cells. Three tert-butoxy groups, which act as electron releasing ('push'), enhance the solubility of phthalocyanine in common organic solvents and reduce the aggregation. Hydroxy substituted 9,10-anthraquinones act as electron acceptors ('pull') for the study of photoinduced electron transfer processes as well as grafting onto nanocrystalline $TiO_2$. The new unsymmetrical zinc phthalocyanine was fully characterized by FTIR, UV-vis, $^1H$ NMR, cyclic voltammetry and differential pulse voltammetry. The new sensitizer was tested in dye-sensitized solar cells, and gave a better performance.

• Journal of The Korean Association For Science Education
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• v.27 no.6
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• pp.477-487
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• 2007

Previous studies show that students have difficulties in understanding and using molecular visualization tools. This study focuses on the ways in which first year chemistry undergraduates use ball-and-stick molecular models to explain the concept of addition reaction and the difficulties that they face using the models. Video recordings of interviews with undergraduates manipulating ball-and-stick models to solve problems related to reaction mechanisms are analysed to determine if they are able to elucidate their understanding with use of models. The results showed that students have difficulties with viewing the ball-and-stick models from the proper perspective and understanding the relationship between the various structures that they have created using the models. They also find the use of ball-and-stick models tedious and prefer drawing molecular structures on paper to explain their ideas. Implications for the teaching using ball-and-stick molecular models are discussed.

• Journal of the Korean Chemical Society
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• v.62 no.3
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• pp.243-252
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• 2018

In this study, we compared 8th graders' macroscopic and microscopic conceptions related to the properties of substances. A test for the basic particle concept and a test for the macroscopic and microscopic concepts of melting point, solubility, and density were developed and administered to 371 students. Their responses were classified into 4 categories on the bases of their understanding of the macroscopic and microscopic concepts. The proportions and characteristics of each category were also analyzed. The analyses of the results revealed that the students who understood the macroscopic concepts had various misconceptions at the microscopic level. Many students had difficulty in understanding not only microscopic concepts but macroscopic concepts. The microscopic responses of the students who did not understand the macroscopic concepts hardly corresponded with their macroscopic level responses. The students who responded correctly to the test for the basic particle concept also had difficulty in understanding the concept of the properties of substances. When they understood the macroscopic concepts, the proportions of the students who understood the microscopic concepts were high. On the bases of the results, educational implications for effective teaching and learning of concepts related to the properties of substances and for improving the future national curricular are discussed.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.137-143
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• 2012

This study analyzed the questions posted on the chemistry Q&A board by students and teachers in a chemistry education homepage, in order to understand the difficulties in learning and teaching chemistry. The different tendencies were found in the contents and the motivations of questions by students and teachers. In Chemistry I, students raised many questions in the 'Water' unit, while teachers raised many ones in the 'Chemical compound in our life' unit. In Chemistry II, students asked many questions in the 'Gas, liquid, solid' unit, while teachers did in 'Chemical reaction and energy' unit. Students' motivations of questioning were 'Explanation of unclear concept', and 'Problem solving', while teachers' motivations were 'Searching information', and 'Question in experiment'. The Q&A board provided a field in exchanging informations needed in learning and teaching chemistry. Educational implications were discussed on the use of Q&A board in chemistry education.

• Journal of Science Education
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• v.34 no.2
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• pp.342-358
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• 2010

By using the concept of 'Resonance' in benzene which stems from a unit dealing with the carbocyclic compounds which is in a text 'Chemistry I', I developed teaching methods based on the history of science. This study was executed to analyze the effect by applying these methods. Seventy 3rd grade male students, who are attending a high school located in the Pohang area were used in this study. I investigated the level of the relative difficulty and the degree of scholastic achievement from each treatment group and controlled group using the concept of Resonance from the preceeding study. In this study, these 70 students divided into two classes- a traditional lecture group consisting of male 35 student, and a group using the history of chemistry consisting of the remaining 35 student and after a specified period, their scholastic achievement was analyzed. As a result of this study, the treatment group scored much higher (50.143) than the controlled group(25.429) in average score and showed significant difference between two groups. Through this study was based on the history of chemistry, after scientists let them realize the process of improving science attitude, and think like scientists, giving conceptual class can get much more efficiency and durability for learning.

• International Journal of Advanced Culture Technology
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• v.11 no.3
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• pp.211-224
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• 2023

This study surveyed 2nd graders of B high school and 1st graders of A university in Gyeongnam on factors such as behavior control and interaction in non-face-to-face classes, easy or difficult concepts presented in chemistry I and general chemistry textbooks. Based on the results of the survey, the effect of changes in the difficulty level of concepts presented in chemistry I and general chemistry and changes in class types (face-to-face and non-face-to-face) on students' academic achievement by level was compared and analyzed. In the face-to-face class, the average score between the first and second semesters was similar according to the change in the difficulty of the concepts presented in chemistry I and general chemistry. In the non-face-to-face class, the average score of chemistry I in the second semester was quite low, and the average score of general chemistry was rather high. In non-face-to-face classes, the average score of chemistry I in the second semester of low-level students was significantly lowered due to changes in the difficulty of the concept and changes in class types on academic achievement by level. In the case of 10% of students at the lower level, the academic achievement of chemistry I decreased in both the second semester regardless of the changes in the difficulty level of concepts and the changes in class types.

• International Journal of Advanced Culture Technology
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• v.11 no.2
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• pp.210-220
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• 2023

We analyzed and compared factors such as changes in the degree of difficulty of concepts presented in Chemistry I textbook, changes in class types (non-face-to-face, face-to-face), etc. on academic achievement by level (upper, middle, and lower). Students from A high school in Gyeongsangnam-do were selected for the subjects of the study. As a result of analyzing the change in the degree of difficulty of concepts, the total score of chemistry I combined by non-face-to-face and face-to-face classes during the second semester was lower than that of the first semester. As a result of analyzing the impact of factors such as changes in conceptual difficulty, changes in class types, etc. on academic achievement by level, students' grades at the 'lower level' by non-face-to-face classes were lower than those by face-to-face classes. In particular, at the lower level of the second semester, there was a large difference in grades between non-face-to-face and face-to-face classes. In the results of these studies, it was found that instructors' active feedback is important to identify difficulties in understanding learning contents for students with low levels of academic achievement and improve them at the same time.

• Journal of The Korean Association For Science Education
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• v.15 no.4
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• pp.437-451
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• 1995

Middle and high school students' conceptual understanding about stoichiometry, gas laws, and diffusion was compared with essay type test and multiple choice test. Whereas achievement of high school students was higher in stoichiometry, that of middle school students who were expected to go to high schools was higher in gas laws and diffusion. When students' achievement was compared to that of American college students, Korean students' achievement was higher in stoichiometry and was similar in gas laws. These results indicate that algorithmic problem solving is more emphasized than conceptual understanding in high schools and that quantitative aspects focused in chemistry education are not helpful in concept understanding. Nevertheless relatively smaller difference between concept understanding and algorithmic problem solving for high school students in this study seems to be from concept learning in middle schools.