N₂O₂계 거대고리 리간드와 중금속 이온과의 착물형성에 관한 연구

최규성,김정,정윤숙 경남대학교 환경문제연구소 1989 환경연구 Vol.11 No.-

The protonation constants for the macrocyclic ligands containing nitrogen and oxygen donors such as 1,12-diaza-3, 4 : 9, 10-dibenzo-5, 8-dioxa-cyclopentadecane(NtnOenH₄), 1, 13-diaza-3, 4 : 10, 11-dibenzo-5, 9-dioxacyclohexadecane(HtnOtnH₄) have been determined by potentiometric titration at 25°C. In order to obtain the stability constants of complexation reactjon of Zn(Ⅱ), Cd(Ⅱ) ion with these ligands, half-wave potential have been measured by polarographic method at 25°C. Protonation constants and stability constants have been found to be effected by the basicities of the macrocyclic ligands and macrocyclic effect.

영구형 항서맥 심박조율기 환자의 장기추적관찰

최현석,이무용,최영진,최성준,김효수,손대원,오병희,이명묵,박영배,최윤식,이영우,이명용 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.5

수목추출물의 생리활성에 관한 연구(Ⅸ) : 아까시나무 심재의 항산화활성 물질 Antioxidative Compounds from Heartwood of Robinia pseudo-acacia

최돈하,이학주,이성숙,김윤근,강하영 한국목재공학회 2002 목재공학 Vol.30 No.4

항산화활성이 우수한 아까시나무 심재 에탄올 조추출물로부터 항산화물질을 탐색할 목적으로 4종의 화합물을 단리하였으며, MS, NMR 등의 분광학적 방법에 의해 그 화학적 구조를 3-β-stigmast-5-en-3-ol(daucosterol)를 비롯하여 스틸베노이드 화합물인 3,3' ,4' ,5-tetrahydroxystilbene과 후라보노이드인 3,3' ,4' ,5' ,7-pentahydroxyflavone(robinetin) 및 3,3' ,4' ,7-tetrahydroxyflavanone(fustin)으로 각각 동정하였다. 단리된 화합물의 프리라디칼 소거능을 측정하여 항산화활성을 검정한 결과, 페놀성 수산기가 5개인 3,3' ,4' ,5' ,7-pentahydroxyflavone은 천연항산화제 및 합성항산화제보다 높은 항산화활성을 나타내어 단리화합물 중 가장 항산화활성이 높은 것으로 나타났다. 또한, 페놀성 수산기가 4개인 3,3' ,4' ,5-tetrahydroxystilbene과 3,3' ,4' ,7-tetrahydroxyflavanone도 천연항산화제인 α-tocopherol보다 높은 항산화활성을 나타내었으나 3-β-stigmast-5-en-3-ol은 항산화활성이 없는 것으로 나타나 프리라디칼 소거능에 의한 항산화활성은 화합물의 페놀성 수산기수에 크게 좌우되는 것으로 판단되었다. 이상의 결과 아까시나무의 높은 항산화활성은 3,3' ,4' ,5' ,7-pentahydroxyflavone. 3,3' ,4' ,5-tetrahydroxystilbene 및 3,3' ,4' ,7-tetrahydroxyflavanone에 기인하는 것으로 사료되었다. Antimicrobial and antioxidative activities on heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. One steroid, stilbene derivatives and two flavonoids were isolated from heartwood of Robinia pseudo-acacia which has been selected due to its high antioxidative activity among the tested species. The structures were determinded as : 3-β-stigmast-5-en-3-ol(daucosterol), 3,3',4,5-tetrahydroxystilbene, 3,3',4',5',7-pentahydroxyflavone(robinetin) and 3,3',4',7-tetrahydroxyflavanone(fustin) respectively on the basis of spectroscopic data and chemical correlations. According to the results of free radical scavenging activity, 3,3',4',5',7-pentahydroxyflavone was evaluated as the highest antioxidative compound among the four compounds and showed higher radical scavenging activity than those of α-tocopherol and butylated hydroxytoluene(BHT), one of the strongest synthetic antioxidants. 3,3',4',5-Tetrahydroxystilbene and 3,3',4',7-tetrahydroxyflavanone showed higher antioxidative activities than that of α-tocopherol. However, 3-β-stigmast-5-en-3-ol did not show free radical scavenging activity. In this regard, it could inferred that high antioxidative activity of extractives of R. pseudo-acacia was derived from 3,3',4',5',7-pentahydroxyflavone, 3,3',4',5-tetrahydroxystilbene and 3,3',4',7-tetrahydroxyflavanone.

수목추출물의 생리활성에 관한 연구(Ⅹ) : 헛개나무 목부의 항균활성 물질 Antifungal Compounds of Hovenia dulcis

최윤정,이학주,이성숙,최돈하 한국목재공학회 2003 목재공학 Vol.31 No.1

항균활성이 우수한 혓개나무 목부 에탄올 조추출물로부터 7종의 화합물을 단리하였으며, 기기분석 결과 flavonoid인 5-hydroxy-7methoxyflavone를 비롯하여 5,7-dihydroxyflavone (chrysin). 5,7-dihydroxyfla-vanone(pinocembrin), 3,5,7-trihydroxyflavanone (pinobanksin), 3,4',5,7-tetrahydroxyflavanone (aroma-dendrin)과 stilbenoid인 3-hydroxy-5-methoxystilbene과 3,5-dihydroxystilbene (pinosylvin)으로 각각 동정되었다. 이들 단리물질에 대한 항균활성을 조사한 결과 stilbenoid인 3-hydroxy-5-methoxystilbene이 공시균주의 생장을 완전히 저해하여 단리물질 중 활성이 가장 높은 것으로 나타났다. 그 다음이 pinocembrin과 pinosylvin으로 Cryphonectria parasitica, Trametes versicolor, Tyromyces palustris 그리고 Trichoderma viride에 대한 높은 균사생장억제율을 나타내어 활성이 우수한 것으로 나타났다. 그러나, flavonoid인 pinobanksin, 5- hydroxy-7-methoxyflavone, chrysin, 그리고 aromadendrin은 항균활성이 낮은 것으로 나타났다. 이상의 결과, 헛개나무 목부 에탄올 조추출물의 높은 항균활성은 3-hydroxy-5-methoxystilbene과 pinocembrin, 그리고 pinosylvin에서 유래된 것으로 사료되었다. Antimicrobial activities of plant extractives were investigated to develop a natural fungicide. Two stilbenoids and five flavonoids were isolated from wood extractives of Hovenia dulcis (Rhamnaceae) which had been selected due to its high antifungal activity among the tested species. The chemical structures of isolated compounds were determinded as : 5-hydroxy-7-methoxyflavone, 5,7-dihydroxy-flavone (chrysin), 5,7-dihydroxyflavanone (pinocembrin), 3,5,7-trihydroxyflavanone (pinobanksin), 3,4',5,7-tetrahydroxyflavanone (aromadendrin), 3-hydroxy-5-methoxystilbene and 3,5-dihydroxystilbene (pinosylvin) on the basis of Mass and NMR spectroscopic data. According to the results of antifungal test, 3-hydroxy-5-methoxystilbene was evaluated as the strongest antifungal compound among the tested compounds and next were pinocembrin and pinosylvin, but those also had high hyphal growth inhibition activities against C. parasitica, T. versicolor, T. palustris and T. viride. However, pinobanksin, 5-Hydroxy-7-methoxyflavone, chrysin and aromadendrin showed very low antifungal activity. In this regard, it could inferred that high antifungal activity of wood extractives of H. dulcis were derived from 3-hydroxy-5-methoxystilbene, pinocembrin and pinosylvin, respectively.

DBME(Discipline-Based Music Education)에 의한 음악과 교육과정의 비판적 분석과 발전 방향 탐색

최윤경,강현석 이화여자대학교 사범대학 교육과학연구소 2005 교육과학연구 Vol.36 No.2

오늘날 음악 교육은 입시 위주의 교육 정책, 국가 경쟁력의 강화라는 표어 아래에서 학교 당국과 교사, 학생, 학부모에게 부담스러운 과목으로 외면당하고 있으며, 음악 교육의 가치와 당위성마저 흔들리는 위기에 직면해 있다. 이러한 위기는 현재까지의 음악 교육이 일반적으로 ‘음악 이론과 기능을 가르치고 음악 활동을 하는 교과’로 인식되어 왔고, 음악과 교육과정 역시 ‘이해해야 할 지식’과 ‘경험해야 할 행위와 활동’을 단순히 나열하고 있었기 때문이라고 할 수 있다. 우리나라와 비슷한 위기에 직면했던 미국은 예술 교육의 정상화를 위해 미술교육에서 DBAE(Discipline-Based Art Education) 이론을 개발하였고, DBAE의 연구 결과에 기초하여 음악 교육의 문제를 해결하고자 연구된 것이 DBME(Discipline-Based Music Education)이다. 이에 본 연구는 DBME의 역사적 배경, 목적과 내용, 특징을 살펴보고, 이를 통해 현행 음악과 교육과정을 비판적으로 분석하였으며, 향후 음악과 교육과정이 ‘사회적?역사적?문화적 맥락을 고려’하고, ‘사고와 탐구 활동을 강조’하고, ‘디지털 중심의 사회적 변화를 수용’하는 음악과 교육과정으로 발전하여야 함을 제안하였다. Today, music education is a burden to teachers, students and parents and music is recognized to difficult subject. The reason is why the purpose of education changes into the university entrance and the policy of economic growth has precedence. So, The value of music education have faced at risk. The reason is that music education was recognized by subject matter that teaches music theory and function and does music activity until now. And music curriculum lists knowledge to understand, and activity to experience. The United States of America that faced at risk similar our country developed DBAE(Discipline-Based Art Education) theory in art education to solve problem of art education. DBME(Discipline-Based Music Education) is based on DBAE and studied to solve problem of music education. DBME involves music-making, musical history, musical aesthetics and musical criticism. Each of these disciplines are related and integrated to provide students with a balance understanding of works of music. This study examines historical background, purpose, contents, characteristic of DBME for theoretical explanation. Through this, current music curriculum is analyzed critically. And the direction of music curriculum is presented as following. So Music curriculum that accommodates engineering, considers social, historical, cultural context, and emphasizes thinking ability is emphasized in the next music curriculum revision.

Co(ll)이온과 N₂O₂계 거대고리 리간드와의 착물형성에 관한 연구

최규성,성찬기,정윤숙 慶南大學校 附設 基礎科學硏究所 1989 硏究論文集 Vol.1 No.-

The protonation constants for the macrocyclic ligands containing nitrogen and oxygen donors such as 1, 12-diaza-3,4 : 9, 10-dibenzo-5, 8-dioxacyclopentadecane(NtnOenH₄), 1, 13-diaza -3,4 : 10, 11-dibenzo-5, 9-dioxacyclohexadecane( NtnOtnH₄) have been determined by potentiometric titration at 25℃. In order to obtain the enthalpy and entropy changes of complexation reaction of Co(II)ion with these ligands, the stability constants have been measured by uv-vis spectrophotometric method at 20~45℃. Protonation constants and stability constants have been found to be effected by the basicities of the macrocyclic ligands. The complexation reactions are exothermic and show the positive entropy changes. ?? studies showed that the stepwise additions of Co(II) ion the macrocyclic ligands of constant concentration induced spectral changes. The large chemical shifts of protons nearest aside the nitrogen were noticeable with the addition of Co(II) ion.

p-Nitrocinnamaldehyde의 가수분해 반응 메카니즘에 관한 반응속도론적 연구

최석남,윤세중,홍춘표 공주대학교 사범대학 과학교육연구소 1984 과학교육연구 Vol.16 No.1

The rate constants of the hydrolysis of p-nitrocinnamaldehyde were determined by ultraviolet spectrophotometer, and a rate equation which could be applied over wide range of pH was obtained. The reaction machanism of hydrolysis of p-nitrocinnamaldehyde especially the catalytic contribution of hydroxide ion, hydroxide ion and water which was not yet studied carefully before in acidic media, could be fully explained by the equation obtained. The rate equation reveals that : below pH 6.0 the reaction is initiated by hydronium ion to p-nitrocinnamaldehyde, at pH 7.0∼9.0 the reaction is initiated by water and hydronium ion competitively and at obove pH 10.0 the reaction is initiated by hydroxide ion to p-nitrocinnamaldehyde.

청소년의 식이행태 조사 : 서울·양평 두 지역간 비교 The Comparison of Urban and Rural Areas

최준호,안동현,최보율,강윤주,백영석,조연규,고복자,남정현 漢陽大學校 精神健康硏究 1998 精神健康硏究 Vol.17 No.-

Thermocouple을 이용한 Buchanan Plugger 표면의 온도상승 분석

조진숙,황윤찬,김선호,황인남,최보영,정영진,정우남,오원만 전남대학교 치의학연구소 2003 구강과학 Vol.15 No.4

This study was performed to confirm the actual temperature rise on the surface of Buchanan plugger by evaluating the temperature rise on the surface of it, the peak temperature of pluggers of various size using thermocouple. The heat carrier system 'System B Heatsource' (Model 1005, Analytic Technologies, USA) and the Buchanan pluggers of F, FM, M and ML sizes are used for this study. The temperature was set to 200 which Dr. Buchanan's "Continuous wave of condensation" technique recommended on digital display and the power level on it was set to 10. The touch mode was used. Five thermocouples were placed in direct contact with the surface of each size of Buchanan's pluggers at 1 ㎜ increments from the tip to the 4 ㎜ length of shank. Each thermocouple was secured with cyanoacrylate adhesive and orthodontic resin block. The two wire leads of each thermocouple were connected to the appropriate channels of Data Logger. This was configured to simultaneously record input from the five thermocouples. The heat control spring was touched for 1, 2, 3, 4 and 5 seconds, and the temperature rise on the surface of the pluggers were measured at 1 sec intervals for more than 5 seconds with an accuracy of 0.01. Ten trials was determined for each plugger. The average of temperature rise and standard deviation was calculated for each size of plugger. The data were statistically analyzed by one-way ANOVA to determine their significance. The results as follows. 1. The position at which the temperature peaked was approximately at 1∼2㎜ far from the tip of Buchanan plugger (p<0.01). 2. The peak temperature was 215.25±2.28℃ in F plugger, 185.94±2.19℃ in FM plugger, 169.51±9.12℃ in M plugger, and 160.79±1.27℃ in ML plugger and the peak temperature was highest in F type and followed by, in descending order, FM type, M type. ML type showed the lowest peak temperature (p<0.01). This results suggest that the actual temperature on the surface of the pluggers does not correlate well with the temperature set on digital display. Heat concentrates around the tip. The larger plugger reveals lower temperature rise relatively.

콘크리트 포장의 플라이애쉬 재활용 방안연구

정영화,최성용,윤경구,용석응,김태경 강원대학교 석재복합신소재제품연구센터 1998 석재연 논문집 Vol.3 No.-

한국 대부분의 고속도로는 콘크리트로 포장되고 있으며, 플라이애쉬를 포장용 콘크리트에서 재활용하면 콘크리트의 성능을 향상시킴과 동시에 경제적 이익과 환경보호에 큰 기여를 할 것이다. 본 연구에서는 플라이애쉬를 포장 콘크리트에 재활용하고자, 플라이애쉬 치환율, 물-시멘트비, 굵은골재 최대치수를 주요실험 변수로 하여 이들이 플라이애쉬를 혼입한 포장용 콘크리트의 역학적 특성에 미치는 영향을 살피기 위해서 실험하여 통계처리 분석하였다. 이러한 분석결과를 바탕으로 포장 콘크리트의 적정배합을 제시하였으며 결과는 다음과 같다. 플라이애쉬를 혼입한 포장콘크리트의 휨강도에 영향을 미치는 인자는 플라이애쉬 치환율이 가장 큰 것으로 나타났으며, 다음으로 굵은골재 최대치수와 물-시멘트비 순으로 영향을 미친다. 또한, 플라이애쉬 치환율과 굵은골재 최대치수의 상관관계가 가장 큰 것을 알 수 있었다. 목표압축강도를 목표 휨강도의 6배로 선택하여 적정구간을 결정하였으나, 적정배합구간이 목표압축강도에 의해서 결정되었다. 이는 플라이애쉬의 작은 수화물이 공극을 효과적으로 채움으로써 휨강도의 증진에 크게 기여하기 때문으로 판단된다. 고속도로 포장에 적용할 수 있는 32mm의 굵은골재 최대치수와 45%의 물-시멘트비를 사용하는 목표 휨강도 45kg/㎠의 적정배합에서는 5.0%까지 플라이애쉬를 치환 가능하고, 50kg/㎠의 적정배합에서는 2.5%까지 치환 가능하다. 공항 포장에 적용할 수 있는 40mm의 굵은골재 최대치수와 37%의 물-시멘트비를 사용하는 목표 휨강도 45kg/㎠의 적정배합에서는 4.5%까지 플라이애쉬를 치환 가능하고, 50kg/㎠의 적정배합에서는 2.0%까지 치환 가능하다. The most of highway in Korea have been paved by concrete since last ten years. The recycling of fly ash in pavement concrete may result in economics, the improvement of concrete quality and the reservation of environment. This paper focused on the series of experiment and statistics analysis with experimental variables such as fly ash substitute ratio, water-cement ratio and maximum size of coarse aggregate in order to investigate the feasibility of recycling of fly ash in pavement concrete, to see the strength characteristics and t propose the optimum mix design based on previous results. The results of experiments and analysis were follows; The fly ash substitute ratio affected most seriously to the flexural strength of concrete among main variables, followed by maximum size of coarse aggregate and water-cement ratio. The interaction between fly ash substitute ratio and coarse aggregate size was the biggest. The optimum mix design was determined by target compressive, which was selected as 6 times of flexural strength. This indicated that the small hydrate of fly ash in concrete filled in effectively and resulted in the enhancement of flexural strength. the optimum mix design for highway pavement concrete with 32mm of maximum size of coarse aggregate and 45% of W/C can incorporate up to 5.0% and 2.5% of fly-ash at 45 kg/cm² and 50 kg/cm² of target flexural strength, respectively. The optimum mix design for airport pavement concrete with 40mm of maximum size of coarse aggregate and 37% of W/C can incorporate up to 4.5% and 2.0% of fly ash at 45 kg/cm² and 50 kg/cm² of target flexural strength, respectively.