• Title/Summary/Keyword: Chemistry Experiment

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The Effect of the 'Chemistry and Experiment' Course Employing Small-Scale Chemistry on Pre-service Elementary Teachers' Attitude toward Laboratory Work and Science Teaching Efficacy (Small-Scale Chemistry를 적용한 '화학 및 실험' 강좌가 초등 예비 교사의 실험 활동에 대한 태도 및 과학 교수 효능감에 미치는 효과)

  • Yoon, Hee-Sook;Yoo, Mi-Hyun
    • Journal of Korean Elementary Science Education
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    • v.26 no.4
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    • pp.449-458
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    • 2007
  • The purpose of this study was to investigate the effect of the 'Chemistry and Experiment' course employing the Small-Scale Chemistry(SSC) experiment on the 30 pre-service elementary teachers' attitude toward laboratory work and their science teaching efficacy. This study also examined the perception of the pre-service elementary teachers about the SSC experiment. In the result, there were found significant interactions between the treatment and prior level in attitude toward laboratory work. The attitude toward laboratory work of low-level pre-service teachers was improved while that of high-level pre-service teachers remained unchanged. However, there was no significant change in their beliefs regarding science teaching efficacy. Through the analysis of questionnaire, it was also found that they had positive perceptions about the SSC experiment, and most of them as pre-service teachers found the SSC experiment helpful to teach chemistry experiments.

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Transverse relaxation-optimized HCN experiment for tautomeric states of histidine sidechains

  • Schmidt, Holger;Himmel, Sebastian;Walter, Korvin F.A.;Klaukien, Volker;Funk, Michael;Lee, Dong-Han
    • Journal of the Korean Magnetic Resonance Society
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    • v.12 no.2
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    • pp.89-95
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    • 2008
  • Function of protein is frequently related with tautomeric states of histidine sidechains. Thus, several NMR experiments were developed to determine the tautomeric states of histidines. However, poor sensitivity of these experiments caused by long duration of magnetization transfer periods is unavoidable. Here, we alleviate the sensitivity of HCN experiment for determining the tautomeric states of histidine residues using TROSY principle to suppress transverse relaxation of $^{13}C$ spins during long polarization transfer delays involving $^{13}C-^{15}N$ scalar couplings. In addition, this experiment was used to assign the sidechain resonances of histidines. These assignments can be used to follow the pH-titration of histidine sidechains.

Analysis of Preservice Chemistry Teachers' Modelling Ability and Perceptions in Science Writing for Audiences of General Chemistry Experiment Using Argument-based Modeling Strategy (논의-기반 모델링 전략을 이용한 일반화학실험에서 글쓰기 대상에 따른 예비화학교사들의 모델링 능력 및 모델링에 대한 인식 분석)

  • Cho, Hye Sook;Kim, HanYoung;Kang, Eugene;Nam, Jeonghee
    • Journal of the Korean Chemical Society
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    • v.63 no.6
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    • pp.459-472
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    • 2019
  • The purpose of this study was to investigate the effect of science writing for different audiences on preservice chemistry teachers' chemistry concept understanding and modeling ability in general chemistry experiment activities using Argument-based Modeling (AbM) strategy. And we also examined preservice chemistry teachers' perceptions of modeling in different audience groups. The participants of the study were 18 university students in the first grade of preservice chemistry teachers taking a general chemistry experiment course. They completed eleven topics of general chemistry experiment using argument-based modeling strategy. The understanding of chemistry concept was compared with the effect size of pre- and post-chemistry concept test scores. To find out modeling ability, we analyzed level of model by each preservice chemistry teacher. Analytical framework for the modeling ability was composed of three elements, explanation, representation, and communication. The questionnaire was conducted to check up on preservice chemistry teacher's recognition of modeling. The result of analyzing the effect of modeling for different audience on the understanding of chemistry concept and modeling ability, the preservice chemistry teachers' were found to be more effective when the level of audience was low. There was no difference in the recognition of modeling between the groups for audience. However, we could confirm that the responses of preservice chemistry teachers are changed in concrete when they have an experience in succession on modeling.

A Comparative Analysis and Improvement of the Fractional Distillation Experiments in the Middle School Science Textbooks (중학교 과학 교과서 분별 증류 실험의 비교 분석 및 개선)

  • Ryu, Oh Hyun;Choi, Moon Young;Song, Ju Hyun;Kwon, Jung Geun;Paik, Seoung Hey;Park, Kuk Tae
    • Journal of the Korean Chemical Society
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    • v.45 no.5
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    • pp.481-490
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    • 2001
  • The purpose of this study was to find out the problems on the fractional distillation experiments in the middle school science textbooks based on the 6th curriculum and to suggest an efficient experiment method for the middle school students. The first step was the classification of the experiments in 8 science textbooks according to heating apparatus and liquid mixtures. The second step was doing each experiment 3 times followed by the experimental process in the textbooks. The third step was developing the alternative experiments for solving the problems found in the second step. The heating method used in the alternative experiments were direct heating, oil bath, and heating mantle. The results of the second step showed that the direct heating experiment of branched round flask was more close to the theoretical prediction than the experiment of water bath heating of branched test tube. Also the direct heating experiment of thermally insulated branched round flask was better than the result of the experiment which was not insulated. The results of the third step showed that the experiment using heating mantle regulated heating power by observing the temperature of distillate gave the closest result to the theoretical prediction. From the above results, it is concluded that the experiment using branched test-tube with water bath heating is not adequate for the fractional distillation and an alternative experiment using insulated branched round flask with heating mantle regulated heating power during experiment is recommended.

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A Study on the Effect of Science Achievement Faculties Improvements in High School Inquiry Chemistry Experiments (탐구 화학 실험을 통한 고등학교 학생들의 과학 성취도 향상에 관한 연구)

  • Choonpyo Hong;Yongyeon Kim
    • Journal of the Korean Chemical Society
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    • v.47 no.5
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    • pp.487-494
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    • 2003
  • In this study, the effects of science achievement faculties improvements upon students' logical thinking, science inquiry skills, experiment attitudes, manipulated skills and inquiry process skills were investigated in high school inquiry chemistry experiments. For this purpose, the participants were 150 students taking the course of high school chemistry class in Anyang-city. Logical thinking and science inquiry skills' data were collected from written tests, inquiry process skills' data were collected from reports and experiment attitudes and manipulated skills' data were collected from classroom observations. As the results of this study, students' inquiry process skills, experiment attitudes and manipulative skills were very low. But other parts except inquiry process skills were significantly increased. And the science achievement of students were improved when continuously inquiry chemistry experiment were applied to students.

Development of Phototactic Test Apparatus Equipped with Light Source for Monitoring Pests (LED광원에 대한 해충 행동반응 monitoring을 위한 주광성 실험장치 개발)

  • Oh, Min-Seok;Lee, Hoi-Seon
    • Journal of Applied Biological Chemistry
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    • v.53 no.4
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    • pp.248-252
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    • 2010
  • This study presented a development of a phototactic apparatus for pest monitoring. We carried out behavioral experiment against various pest species by using the phototactic chamber. Consequently, the phototactic apparatus was confirmed suitable result of behavioral experiment. Therefore, we believed that the test apparatus help to understand the phototactic responses of various pests.

Development of Online Quantum Chemistry Experiment Environment Based on Computational Science Platform (계산과학플랫폼 기반 온라인 양자화학 실험 환경 개발)

  • Jeon, Inho;On, Noori;Kwon, Yejin;Seo, Jerry H.;Lee, Jongsuk Ruth
    • Journal of Internet Computing and Services
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    • v.21 no.5
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    • pp.97-107
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    • 2020
  • This paper introduces an online experiment environment based on a computational science platform that can be used for various purposes ranging from basic education to quantum chemistry and professional quantum chemistry research. The simulation environment was constructed using a simulation workbench and simulation workflow, which are execution environment services of Science App provided by the computational science platform. We developed an environment in which learners can learn independently without an instructor by selecting experiment topics that can be used in various areas of chemistry, and offering the learning materials of the topics in a form of e-learning content that includes theory and simulation exercises. To verify the superiority of the proposed system, it was compared with WebMO, a state-of-the-art web-based quantum chemistry simulation service.

Identification of Anthocyanins from Pigmented Rice Seeds

  • Lee, Hun-Joong;Oh, Se-Kwan;Choi, Hae-Chune;Kim, Soo-Un
    • Applied Biological Chemistry
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    • v.41 no.4
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    • pp.257-260
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    • 1998
  • Anthocyanins pigments were isolated from the pigmented rice seeds (cultivar Killimhuk-mi) by a combination of Sephadex LH-20 and preparative high performance liquid chromatographies. Four anthocyanins were identified by their chromatographic, spectral and chemical properties. The major pigment was cyanidin 3-glucoside and cyanidin 3-oxalyl-glucoside was found in the rice for the first time.

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