• Journal of the Korean Chemical Society
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• v.53 no.5
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• pp.570-584
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• 2009

The purpose of this study was to find out high school students' perception on psychologicallearning environment generated by science teachers and their attitude change related to science. The subjectsconsisted of 539 freshmen in a boys' high school pre-applied of common school group in S city. This study wasconducted with students' perception survey and classification of teachers' features according to it. The surveyabout science-related attitude was also made in early 1st semester and 2nd semester, and the students showingthe great attitude change related to science were interviewed. The results of this study revealed that statistically,students had a more positive perception on female teachers than on male ones and that according to their teachers,there were clear different in the psychological learning environment perceived by students. As for the relation of teachers' features and students' attitude change, it showed the negative effect only when the teacher was incharge of only one class, but in most of the cases, there was no meaningful correlation. The semi-structuredinterview with students with great attitude change related to science indicated that the main cause of the changewas the achievement they made in class. The interview showed that the change related to science happenedunder the indirect influence of teachers rather than direct influence. Furthermore, students wanted scienceteachers to meet the science class possessing various instruction behaviors and support behaviors. Therefore,science teachers playing an important role in students' choice of career should make efforts to realize thelearner-centered curriculum and change students' science-related attitude into a positive direction.

• Journal of The Korean Association For Science Education
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• v.21 no.5
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• pp.944-967
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• 2001

The purpose of this study is to compare and analyze secondary school chemistry education in Korea and China in order to identify implications for the improvement of Korean chemistry education. The school systems, curricula, and teacher education related to secondary chemistry education of both countries were compared and analyzed. The 6-3-3-4 school system is used in both countries, and national school curricula are formulated by the Ministries of Education in both countries. The 1996 chemistry curricular standard for advanced middle schools in China, and 1997 chemistry curriculum for Korean high schools were compared in several aspects, followed by comparisons of chemistry teacher education in both countries. Based on the comparative analysis of chemistry education, some ideas and issues which provide implications for improving Korean high school chemistry education were identified. Chemistry teaching in the junior secondary schools, tentative implementation of curricula, required course work in chemistry, structure of curricula, oral assessments, probation of teachers and other issues are identified and discussed in this study.

• Hwankyungkyoyuk
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• v.14 no.2
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• pp.40-50
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• 2001

To meet the objectives of environmental education, teachers especially have to perceive the importance of environmental education, comprehend various characteristics of teaching/learning methods, and be able to conduct classes by choosing proper teaching/leaming methods in accordance with a specific purpose and educational focus about environmental education. Therefore, it Bs necessary to investigate the current status of Korean environmental education and provide teachers with appropriate environmental teaching/leaming methods. To this end this study aims to examine Korean science teachers'perceptions'on environmental education and the kind of teaching/learning methods which can be utilized in environmental education. Teachers who completed the survey were 135 science teachers from middle and high schools in Seoul, and 126 social science teachers from Kyoungki province. The majors of the science teachers were in physics, chemistry, biology, geology, and earth science. Also, there was one teacher who majored in special education. For social science teachers two majors were common, geography and general sociology. After analysis of the data from the surveys the results are as follows. First, science and social science teachers in middle and high school recognized the necessity of environmental education in school education. Second, most teachers had applied environment related topics to their subject of study occasionally, but they mostly concurred that environment related contents should be included in their textbooks. Third, science teachers agreed that field trip, discussion, and the STS approach were the most proper methods for environmental education, and social science teachers agreed that field trips, inquiry, and discussion were the most appropriate methods for a teaching environment. They realized that they should decide good teaching-learning methods appropriate to the objectives and content needed for effective environmental education as they selected different teaching-learning methods according to detailed environmental objectives and contents in their textbooks.

• Bulletin of the Korean Chemical Society
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• v.29 no.3
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• pp.546-550
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• 2008

The title compound of nicotinato lead(II) complex [Pb$(C_5H_4NCOO)_2$] has been optimized at B3LYP/LANL2DZ and HF/LANL2DZ levels of theory. The calculated results show that the lead(II) ion adopts 2- coordinate geometry, which is the same as its crystal structure and different from the 4-coordinate geometry of isonicotinato lead(II) complex. Atomic charge distributions indicate that during forming the title compound, each nicotinic acid ion transfers their negative charges to central lead(II) ion. The electronic spectra calculated by B3LYP/LANL2DZ level show that there exist two absorption bands, which have some red shifts compared with those of isonicotinato lead(II) complex and the electronic transitions are mainly derived from intraligand $\pi$ -$\pi$ transition and ligand-to-metal charge transfer (LMCT) transition. CIS-HF method is not suitable for the system studied here. The thermodynamic properties of the title compound at different temperatures have been calculated and corresponding relations between the properties and temperature have also been obtained. The second order optical nonlinearity was calculated, and the molecular hyperpolarizability was $1.147754{\times}10^{-30}$ esu.

• Journal of the Korean Chemical Society
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• v.35 no.1
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• pp.64-69
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• 1991

Kinetics of the reaction of p-methylphenacyl arenesulfonates with pyridine in acetonitrile were investigated by an electric conductivity method at 1∼2000 bars and 35∼55$^{\circ}C$. The rates of these reactions were increased with raising pressures and temperatures. The activation enthalpy(${\Delta}H^{\neq}$), entropy(${\Delta}S^{\neq}$) and activation volume(${\Delta}V^{\neq}$) of the reaction were obtained with the rate constants. Activation volume and entropy were both negative valued, and activation enthalpy was positive. The acteivation parameters (${\Delta}V^{\neq}$ and ${\Delta}S^{\neq}$) were decreased with increasing pressure. From all of the above results, it was found that this reaction proceeds on the S$_N$2 in which C${\cdots}$O bond breaking is more advanced as pressure increases.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.611-620
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• 2010

The purpose of this study was to explore the structure and content of chemistry teacher's explanations from the perspective of 'persuasion'. Especially, this study was to explore how the argument structure and the conceptual change constructs in chemistry teachers' explanations were established and interacted. Data were collected from chemistryI classes considering the gas unit which includes kinetic theory of gas, Graham's law, Boyle's law, and Charles' law. The classes were vediotaped and transcribed. The transcriptions were analyzed with Toulmin's argument frame and the two constructs of conceptual change model; the conceptual ecology and the status of a conception to interpret the persuasive structure and content of the teacher's explanations. As the results of this study, four explanatory discourses which show various persuasive explanations in chemistry classes. Based on this results, discussion and implications for effective teachers' explanations in chemistry classes were presented.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.96-106
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• 2008

The purpose of this study was to identify the actual conditions of operation in school and investigate the perceptions of science teachers and students regarding the 7th elective-centered curriculum of high school science subjects. For this study, a questionnaire survey was conducted for the selected subjects including 127 high school science teachers and 763 high school students in their third year who had experienced the 7th elective-centered curriculum. As a result of the study, concerning the way to present the elective subjects of science, many cases were the alternative way and the group-elective way in humanity courses while natural science courses had the alternative way and the free-elective way in most cases. In other words, in many cases, the right of elective was given within a limited range. The result of the investigation on science teachers' perceptions on the elective-centered curriculum was that negative views dominated as a whole. Especially, earth science teachers showed the most negative attitudes. The number of biology and chemistry teachers who supported students' right to opt subjects were lower than that of physics teachers and earth science teachers who were against it. To help students make a right choice, many viewed that the system of the college Scholastic Ability Test should be complemented in order to prevent any disadvantage to each elective subject or that it was necessary to have systematic and realistic career education. As the result of investigating the perception of high school students in their third year regarding the elective-centered curriculum, they were usually not very satisfied with it. As the reason for it, many said the selection right was limited. Many others also expressed that there were lack of public relations and education on subjects and careers. Based on these results, limits still exist in accepting all demands although there are a lot of efforts made to smoothly adjust supply and demand of science teachers as well as students' electives in the field of school. It is considered necessary to come up with counterplan and complements to prevent basic science from being neglected or lower academic achievement in the subject of science from happening, and at the same time to harmoniously deal with supply and demand of science teachers as well as the issues of students' demands given the actual conditions of school.

• Journal of The Korean Association For Science Education
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• v.32 no.8
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• pp.1356-1366
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• 2012

As the recent demand for human resources in science, technology, engineering, and mathematics (STEM), the development of professional STEM teacher is called worldwide. It is becoming a critical need in teacher education in order to educate student teachers, and prepare pre-service and beginning teachers for high quality of teaching competency. To promote the competency for $21^{st}$ century STEM teachers, the epistemology of technological pedagogical content knowledge (TPACK) is currently considered as the essential qualities of knowledge for highly qualified teachers. The aim of this study is explore the effect of case-based learning approach on TPACK competency of pre-service STEM teachers. In order to develop the pre-service teachers' competency regarding effective integration of technologies into teaching specific content areas, a series of innovative case study teaching in science and mathematics was presented to 43 participants of pre-service physics, chemistry, biology, mathematics, and computer teachers during a course of information and communication technology (ICT) in Education at Khon Kaen University, Thailand. After finishing a case presentation, the pre-service teachers were encouraged into a forum of critical open discussion by considering the potential impact of the case and the TPACK framework. They were investigated instructional design competency of using ICT tools into student learning process and their personal beliefs about ICT in educational process both before and after. The participant's reactions and learning was evaluated by using a self-reported questionnaire and an implementation log of content-specific learning process design, respectively. Results showed a change of their beliefs and the transformation of their TPACK competency in STEM teaching. In an effort to better serve the needs of high quality STEM teachers, the results of this study illustrated that the competency of TPACK could be particularly considered as a core attributes for future STEM teachers. By the way, case-based learning approach can play an effective part in preparing and professing the TPACK competency for STEM teachers.

• Journal of the Korean earth science society
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• v.34 no.5
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• pp.435-449
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• 2013

The purpose of this study was to investigate the difference of teachers' interaction with their students when teaching science in New York (NY) and in Korea. As part of the 2011 Korean International Teacher Fellows (KITF), supported by the Ministry of Education, Science and Technology (MEST) and the National Institute for International Education Development (NIIED), Korean science teachers observed, for six months, New York's science classes in terms of how teachers interact with their students and how students learn science during science instruction. The participants were 10 science teachers in five middle and high schools that taught Physics, Chemistry, Biology, Earth Science, and Environment Science in NY. The National Board for Professional Teaching Standards (NBPTS, 2003) and Instruction as Interaction (Cohen et al., 2003) were used as an instrument to identify each teacher's teaching and classroom interaction. Several characteristics of science classes in NY were revealed, which are different from Korean science classes. First, science teachers in NY dominantly put more focus on their subject of teaching during science interaction while, Korean science teachers not only teach science but also do counseling to students as a homeroom teacher. Second, science teachers in NY acknowledged the students' individuality and have positive experiences of professional development supported by their school and district more than Korean science teachers do. Third, science teachers in NY sometimes showed limited knowledge about the concepts of science and lack of collaboration with other science teachers. This characteristics may prevent the school from strengthening its subject program and keeping equity across the grade levels and courses.

• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.371-378
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• 1989

Kinetics of the substitution reaction of [pt[dien]X]$^+$(X = $Cl^-$, $Br^-$, $I^-$) with NO2- in aqueous solution were investigated by a spectrophotometric method at $20-35^{\circ}C$ and 1-1500 bars. The rates of these reactions were increased with raising temperature and pressure. The relative reactivities of replaceable ligands in [pt[dien]X]$^+$ follow the order ($Cl^-$ > $Br^-$ > $I^-$). Activation volumes (${\mid}{\Delta}V^{\neq}{\mid}$) were large negative values and decreased with raising temperature. First ($k_1$) and second($k_2$) order rate constants of these reactions were determined at $25^{\circ}C$ and both $k_1$ and $k_2$ were increased with raising pressure and activation volumes (${\Delta}{V_1}^{\neq}$, ${\Delta}{V_2}^{\neq}$) for the $k_1$ and $k_2$ path were large negative values respectively. The $k_1$ and $k_2$ of these reactions were determined at 1 bar and these values were increased with raising temperature. Activation parameters of $k_1$ and $k_2$ path were determined, therefore it can be inferred frp, these results that the substitution reactions of [pt[dien]X]$^+$ with ${NO_2}^-$ proceed through on associative (A) mechanism independent of a leaving groups and reaction paths.