• 한국압력기기공학회 논문집
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• 제7권3호
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• pp.15-22
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• 2011

The chemistry factor and RTPTS margin for domestic reactor pressure vessel materials were analyzed by using the surveillance data which have been obtained from 8 nuclear power plants in Korea. The surveillance data have been used to assess the integrity of the pressure vessel under the pressurized thermal shock (PTS) event. The chemistry factor, which is determined by the Cu and Ni contents of vessel materials, is considered a proper tool to assess the $RT_{PTS}$. The chemistry factors, which were obtained from the surveillance data of domestic reactor pressure vessels, were investigated and compared with those of Regulatory Guide 1.99 in this study. Regressions for ${\Delta}RT_{NDT}$ were performed to expect the chemistry factor as a function of Cu and Ni, and to estimate $RT_{PTS}$ margin. The margin analysis was performed by comparing the regression graphs and standard deviations with those of Regulatory Guide 1.99. The standard deviations calculated by using the domestic surveillance data for base metal and welds are almost same as the standard deviations which are suggested on Regulatory Guide 1.99, Rev.2.

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4201-4203
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• 2012

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2511-2514
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• 2013

• 대한화학회지
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• 제64권2호
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• pp.119-129
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• 2020

과학 고등학교에서 다양한 재능을 지닌 학생들의 효과적인 교수- 학습 활동을 위해서, 교수자는 학생들의 다양한 재능과 교과목의 특성에 따라 자연세계의 정보를 인식하고 처리과정에서의 개인차를 이해하는 것이 중요하다. 본 연구의 목적은 수학/과학 성취도의 교과 간 상관 및 요인 분석으로 과학고 학생들의 화학 교과에 대한 인식을 규명하는데 있다. 아울러 R&E 학급에 따른 화학 교과의 인식을 알아보고자 하였다. 연구 대상은 입학 전형과 교육과정의 개편 시기에 따른 G과학고 3개년 입학생(296명)이 주 연구 대상자이고, 경남·울산 지역 2개 과학고를 포함하였다. 성취도의 상관 및 요인 분석은 SPSS 25를 이용하여 탐색적 요인분석법으로 수행하였다. 본 연구의 수행 결과, 다음과 같은 결론을 얻었다. 첫째, 수학·과학 성취도 간의 상관분석에서 화학의 Pearson 상관계수는 다른 교과목들에 비해 높은 정적 상관을 보이는 것이 확인되었다. 둘째, 수학·과학 성취도의 요인 분석에서 요인 지표는 수리-논리(수학, 물리)와 자연 이해(생명과학, 지구과학)의 2개 요인으로 구분되는 것이 확인되었다. 셋째, 요인 분석에서 화학 교과는 수리-논리와 자연 이해 능력이 모두 요구되는 교과로 인식하고 있음을 확인할 수 있었다. 마지막으로, R&E 학급에 따라서 화학 교과에 대한 학생들의 인식이 다르다는 것을 확인하였다. 즉, R&E 화학반 학생들은 다른 학생들과 달리 화학 교과를 수리-논리가 요구되는 과목으로 인식하고 있음이 확인되었다.

• Natural Product Sciences
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• 제27권2호
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• pp.134-139
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• 2021

A new cipadesin limonoid, i.e. 3-epi-cipadonoid C (1), and a new tirucallane triterpene, i.e. hispidol B 3-palmitate (3), have been isolated from the seeds and fruit peels extract of Sandoricum koetjape, respectively. Along with these compounds the known limonoid, cipaferen G (2), and two pentacyclic triterpenes, bryonolic (4) and bryononic (5) acids, were also isolated. The strucrures of the new compounds were elucidated by the analysis of NMR and mass spectral data. Compounds 1 - 5 were evaluated as the inhibitor of receptor tyrosine kinases (EGFR, Epidermal Growth Factor Receptor; HER2, HER4, Human Epidermal growth factor Receptor 2, -4; IGFR, Insulin-like Growth Factor Receptor; InsR, Insulin Receptor; KDR, Kinase insert Domain Receptor; PDGFRα, and PDGFRβ, Platelet-Derived Growth Factor Receptor-α and -β). The results showed only 1 and 3 that have weak activity against InsR.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.74-77
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• 1994

Rare earth elements (REE) were individual separated by applying the gradient elution via HPLC using ${\alpha}-hydroxyisobutyric$ acid (HIBA) as an eluent. However, the overlap of Y and Dy peaks was too severe to obtain the resolution of these two peaks. The target transformation factor analysis (TTFA) was applied to resolve the elution peaks of Y and Dy. [A]$_{raw}$ formed from the absorbances of mixed solution was factor analyzed. The abstract factor analysis(AFA) was used to determine the number of components that contributed to the poorly resolved peaks. The error theory in the AFA showed that the number of components was 2. The test vectors which correspond to pure component were selected from the standard solutions of Y and Dy. TTFA was accomplished by target testing. The results showed that the resolution of two peaks as well as the determination of Y and Dy were possible by the factor analysis.

• Bulletin of the Korean Chemical Society
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• 제14권3호
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• pp.367-370
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• 1993

• Biomolecules & Therapeutics
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• 제24권2호
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• pp.184-190
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• 2016

Rosa rugosa Thunb, a deciduous shrub of the genus Rosa, has been widely used to treat stomach aches, diarrhoea, pain, and chronic inflammatory disease in eastern Asia. In recent years, our research team has extensively studied the Rosa rugosa flower extract, and specifically undertook pharmacological experiments which have optimized the extraction process. Our methods have yielded a standard extract enriched in phenolic compounds, named PRE. Herein, we expand our efforts and evaluated the anti-inflammatory activity of PRE on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages. PRE significantly inhibited production of nitric oxide (NO), prostaglandin $E_2(PGE_2)$, tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and interleukin $1{\beta}$ (IL-$1{\beta}$), as well as expression of their synthesizing enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase2 (COX-2). Furthermore, PRE inhibited activity of mitogen-activated protein kinases (MAPK) as well as nuclear factor-kappa B (NF-${\kappa}B$) signaling pathway. Our findings are the first to explain the anti-inflammatory mechanism by PRE in LPS-stimulated macrophages. Given these results, we propose that PRE has therapeutic potential in the prevention of inflammatory disorders.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3405-3409
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• 2013

The activation of heat shock factor 1 (HSF1) can be induced by the changes in environmental pH, but the mechanism of HSF1 activation by acidification is not completely understood. This paper reports that a low pH (pH~6.0) can trigger human HSF1 activation. Considering the involvement of the imidazole group of histidine residues under acid pH stress, an in vitro EMSA experiment, Trp-fluorescence spectroscopy, and protein structural analysis showed that the residue, His83, is the essential for pH-dependent human HSF1-activation. To determine the roles of His83 in the HSF1-mediated stress response affecting the cellular acid resistance, mouse embryo fibroblasts with normal wild-type or mutant mouse HSF1 expression were preconditioned by heating or pH stress. The results suggest that His83 is essential for HSF1 activation or the HSF1-mediated transcription of heat shock proteins, in protecting cells from acid pH stress.

• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1801-1806
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• 2004

Ligand-based quantitative structure-activity relationship (QSAR) studies were performed on indolinones derivatives as a potential inhibitor of the protein tyrosine kinase of fibroblast growth factor receptor (FGFR) by comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) implemented in the SYBYL packages. The initial X-ray structure of docked ligand (Su5402) to FGFR was used to minimize the 27 training set molecules using TRIPOS force field. Seven models were generated using CoMFA and CoMSIA with grid spacing 2 ${\AA}$. After the PLS analysis the best predicted CoMSIA model with hydrophobicity, hydrogen bond donor and acceptor property showed that a leave-one out(LOO) cross validated value $({r^2}_{cv})^$ and non-cross validated conventional value $({r^2}_{ncv})^$ are 0.543 and 0.938, respectively.