붕소를 함유하지 않는 E-glass fiber의 제조 및 특성에 대한 연구

이지선,임태영,이요셉,이미재,황종희,김진호,현승균,Lee, Ji-Sun,Lim, Tae-Young,Lee, Yo-Sep,Lee, Mi-Jai,Hwang, Jonghee,Kim, Jin-Ho,Hyun, Soong-Keun 한국결정성장학회 2013 韓國結晶成長學會誌 Vol.23 No.1

E-glass 섬유는 항공기, 자동차, 레져기구의 복합재료 보강용으로 가장 널리 사용되는 유리섬유이다. 그러나 최근 E-glass 섬유의 원재료비 상승, 환경문제 및 화학적 저항성과 기계적 특성을 향상시키기 위해 산화붕소 함량을 8 %에서 0(제로)까지 감소시키는(소위 'Boron free E-glass'라고 불리는) 연구가 진행되고 있다. 본 연구에서는 'BF(Boron free E-glass)' 조성의 벌크유리와 섬유유리를 제조하고, 열적특성 및 광학적특성을 평가하였다. 5~10 %의 서로 다른 알루미나 함량을 갖는 배치를 $1550^{\circ}C$에서 2시간 용융하여 'BF(Boron free E-glass)'가 얻어졌고, 81~86 %의 높은 가시광투과율, $4.2{\sim}4.9{\times}10^{-6}/^{\circ}C$의 낮은 열팽창계수, $907{\sim}928^{\circ}C$의 연화점을 갖는 투명하고 맑은 유리가 얻어졌다. 'BF' 섬유 시편에 대한 화학적내구성 시험에 있어서는 알루미나 함량이 높아질수록 더 좋은 침식저항성을 나타냄을 확인할 수 있었다. E-glass fiber is the most widely used glass fiber for reinforced composite materials of aircrafts, automobiles and leisure equipments. But recently researches are being progressed to reduce boric oxide from 8 % to 0 (zero), as is called 'Boron free E-glass', because of increasing material cost, environmental problem, and improving chemical resistance and mechanical properties of E-glass fiber. In this study, we fabricated the bulk glass and fiber glass of 'Boron free E-glass (BF) compositions', and characterized thermal properties and optical properties. 'Boron free E-glass (BF)' was obtained by the melting of mixed batch materials at $1550^{\circ}C$ for 2 hrs with different $Al_2O_3$ compositions 5~10 %. We obtained transparent clear glass with high visible light transmittance value of 81~86 %, and low thermal expansion coefficient of $4.2{\sim}4.9{\times}10^{-6}/^{\circ}C$ and softening point of $907{\sim}928^{\circ}C$. For the chemical resistance test of 'BF' fiber samples, we identified that the higher alumina contents gives the better corrosion resistance of glass fiber.

신생아기에 새로운 CPS1 유전자 돌연변이가 확인되고, 간세포이식 시행 받은 Carbamoyl phosphatase synthetase 1 deficiency 1례

이지선,양아람,김진섭,박형두,이상훈,이석구,조성윤,진동규,Lee, Jisun,Yang, Aram,Kim, Jinsup,Park, Hyung-Doo,Lee, Sanghoon,Lee, Suk-Koo,Cho, Sung Yoon,Jin, Dong-Kyu 대한유전성대사질환학회 2017 대한유전성대사질환학회지 Vol.17 No.1

Carbamoyl phosphate synthetase 1 (CPS1) 결핍은 요소회로 이상 질환 중 하나로 상염색체 열성으로 유전되며 2q35 염색체에 존재하는 CPS1 유전자 변이로 발생된다. CPS1의 완전한 결핍을 가진 경우 신생아 시기에 빠르게 진행하는 고암모니아혈증으로 발현한다. 신생아 시기의 심한 고암모니아혈증은 즉각적인 치료를 받지 않을 시 심각한 뇌 손상, 혼수, 사망에 이르기에 진단 시 응급 투석과 체계적인 집중 치료가 필요하다. 본 증례는 생후 4일 째 신생아실에서 발열, 경련, 고암모니아혈증이 확인되어 생화학적, 분자유전학적 방법으로 두 개의 새로운 변이 c.1117G>C (p.Ala373 Pro)와 c.1883G>T (p.Gly628Val)가 이형접합체로 발견되고 CPS1 결핍이 진단된 신생아에서 응급 투석 및 집중치료와 함께 궁극적인 치료인 간이식 전 간세포이식술을 생후 1개월에 시행하여 반복적인 고암모니아혈증 발생을 막고 불가역적인 신경손상을 예방하여 현재 생후 6개월까지 단기간 경과관찰 결과 성장과 발달 및 신경학적 예후가 좋음을 보고하는 바이다. Carbamoyl phosphate synthetase 1 deficiency (CPS1D) is an autosomal recessive disorder of the urea cycle that causes hyperammonemia. Two forms of CPS1D are recognized: a lethal neonatal type and a less severe, delayed-onset type. Neonatal CPS1D cases often present their symptoms within the first days of life. Delayed-onset cases are predominantly adolescents or adults, and infantile delayed-onset cases are rare. Severe hyperammonemia in the neonatal period leads to serious brain damage, coma, and death if not treated promptly. Therefore, early diagnosis and acute treatment are crucial. Despite the improvement of treatments, including continuous hemodialysis, ammonia-lowering agents, and a low-protein diet, the overall outcome of severe forms of hyperammonemia often remains disappointing. As the liver is the only organ in which ammonia is converted into urea, liver transplantation has been considered as an elegant and radical alternative therapy to classical dietary and medical therapies. However, liver transplantation has many disadvantages, such as a considerable risk for technical complications and perioperative metabolic derangement, especially in neonates. Additionally, there is a lack of suitable donor organs in most countries. According to recent studies, liver cell transplantation is a therapeutic option and serves as a bridge to liver transplantation. Here, we report a Korean CPS1D patient with novel mutations in CPS1 who was treated by liver cell transplantation after being diagnosed in the neonatal period and showed a good neurodevelopmental outcome at the last follow-up at six months of age.

섬유화 온도 변화에 따른 E-glass fiber의 물리적 특성

이지선,이미재,임태영,이영진,전대우,현승균,김진호,Lee, Ji-Sun,Lee, MiJai,Lim, Tae-Young,Lee, Youngjin,Jeon, Dae-Woo,Hyun, Soong-Keun,Kim, Jin-Ho 한국재료학회 2017 한국재료학회지 Vol.27 No.1

E (Electric) -glass fibers are the most widely used glass fibers, taking up 90 % of the long glass fiber market. However, very few papers have appeared on the physical characteristics of E-glass fibers and how they depend on the fiberizing temperature of fiber spinning. Glass fiber was fabricated via continuous spinning process using bulk E-glass. In order to fabricate the E-glass specimen, raw materials were put into a Pt crucible and melted at $1550^{\circ}C$ for 2hrs; mixture was then annealed at $621{\pm}10^{\circ}C$ for 2hrs. The transmittance and adaptable temperature for spinning of the bulk marble glass were characterized using a UV-visible spectrometer and a viscometer. Continuous spinning was carried out using direct melting spinning equipment as a function of the fiberizing temperature in the range of $1175{\sim}1250^{\circ}C$, while the winder speed was fixed at 500 rpm. Subsequently we investigated the physical properties of the E-glass fiber. The average diameter of the synthesized glass fiber was measured by optical microscope. The mechanical properties of the fiber were confirmed using a UTM (universal materials testing machine); the maximum tensile strength was measured and found to be $1843{\pm}449MPa$ at $1225^{\circ}C$.

유네스코 지속가능발전교육 공식프로젝트에 나타난 공간스케일의 유형

이지선,Lee Ji Sun 글로벌교육연구학회 2015 글로벌교육연구 Vol.7 No.2

유네스코 지속가능발전교육 공식프로젝트는 다른 조직이나 집단에 비해 지속성, 광범위성, 제도화 및 영향력을 지닌다. 2011년부터 2014년까지 총 51개의 유네 스코 지속가능발전교육 공식프로젝트를 분석한 결과 나타난 공간스케일 유형은 4개의 기본 스케일과 11개의 연계 스케일 유형이다. 공간스케일 유형의 빈도를 분 석한 결과는 다음과 같다. 첫째, 연계스케일 유형(69.6%)이 기본스케일 유형 (30.4%)에 비해 많이 나타난 것은 개별 공간스케일 중심 활동보다 여러 공간스케 일에서 활동이 이루어짐을 의미한다. 둘째, 기본스케일 유형 중 글로벌 스케일 (9.5%) 국지적, 지역적 스케일 유형(각각 7.6%), 인터내셔널 스케일(5.7%)이 나타난 것은 교육 내용이 공정무역, 빈곤감소, 평화, 인권 등 글로벌 수준에서 구성 되어있으며, 내 주변의 문제를 해결하고 지속가능한 지역개발을 위한 다양한 실천 프로그램을 실시함에 기인한다. 셋째, 연계스케일 유형 중 국지(지역)-글로벌 연 계 스케일이 36.3% 나타난 것은 지구공동체의 지속가능발전을 위한 교육을 지향 하는 유네스코 지속가능발전교육 공식프로젝트의 교육 내용이 글로벌 차원에서 계 획되었으며 지구공동체의 문제를 나의 문제로 인식하고 주변에서부터 실천하는 프 로그램으로 구성되어 있음을 알 수 있다. Korea UNESCO ESD Official Project sustainability compared to other official organizations and groups and has a wide range of gender, institutionalization and influence. 2011-2014 a total of 51 Korea UNESCO ESD Official Project presented the results of analyzing the spatial scale type of formal education projects are 4 basic types of scale and 11 connection types of scale. First, connection types of scale (69.6%) appeared more than basic types of scale (30.4%) refers to the activities in various space scales than the individual scale space center activities. Second, In basic types of scale the global scale (9.5%), local and regional scale type (7.6%), international scale (5.7%) appears this curriculum is composed in fair trade, poverty reduction, peace, human rights and global levels which is due in solving the problems around me, and carried out various action programs for sustainable regional development. Third, regional (local) - global connection types of scale of education represented 36.3% of the contents of Korea UNESCO ESD Official Project oriented education for sustainable development of the global community was planned at the global level in the global community. It is aware of the problem to my problems and found that contains the program to action from the surrounding.

정밀 지오이드 구축을 위한 자료처리의 최적 변수 결정

이지선,권재현,Lee, Ji-Sun,Kwon, Jay-Hyoun 한국공간정보학회 2009 한국공간정보학회지 Vol.17 No.3

기존의 우리나라 지상중력자료는 자료의 분포 및 정밀도에 있어서 문제점을 가지고 있었고 이러한 문제를 해결하기 위하여 2008년 항공중력측정을 통하여 정밀도 1.56mGal의 항공중력자료를 확보한 바 있다. 그러나 항공중력자료는 비행고도 상에서 획득된 값으로 기존의 지상중력자료 및 해상중력자료와 병합하기 위해서는 지표면 상의 값으로 환산되어야 한다. 또한 다양한 자료를 융합하여 정밀한 지오이드를 계산하기 위해서는 Stokes' 적분반경, Stokes' kernel 및 지형 효과 계산 반경 등의 많은 변수들을 최적으로 고려하여야 한다. 본 연구에서는 지상 및 항공중력자료의 분포 및 특성을 고려하여 보다 정밀한 지오이드 결정을 위한 최적의 매개변수들을 결정하고자 하였다. 선정된 최적 변수들을 적용하여 지오이드를 계산한 결과, 항공중력 및 지상중력 기반의 두 지오이드는 평균 -16.95cm, 표준편차 ${\pm}8.50cm$의 차이를 나타내었는데, 이는 지상 및 항공중력자료의 분포와 지상중력자료에 포함된 오차에 기인한 것으로 판단된다. 향후 본 연구에서 고려한 매개변수 외에도 다양한 하향연속 방법, 지형효과 계산 방법이 지오이드에 미치는 효과와 추가적으로 확보한 중력 및 GPS/Leveling 자료, 해상중력자료를 포함하였을 때의 효과에 대한 연구도 진행되어야 할 것이다. To solve the problems of distribution and quality on land gravity data, airborne gravity survey was performed in 2008 obtaining the airborne gravity data with accuracy of 1.56mGal. Since airborne gravity data is the obtained at the flight height, it is necessary to convert the airborne gravity data to the surface to combine various gravity data and compute precision geoid. In addition, Stokes' integral radius, Stokes' kernel and the radius of terrain effect computation should be optimally determined to calculate precision geoid. In this study, we made an effort to decide the optimal parameters based on the distribution and the characteristic of gravity data. Then, two geoid models were calculated using the selected parameters and the difference of geoid was calculated with mean of -16.95cm and the standard deviation of ${\pm}8.50cm$. We consider that this difference is due to the distribution and errors on the gravity data. For future work, the study on the effect of geoid with newly obtained land gravity data ship-borne gravity data and GPS/Leveling data should be conducted. Furthermore, the study on the downward continuation and terran effect calculation should be studied in detail for better precision geoid construction.

한국인의 항결핵제에 의한 간독성 위험인자 예측

이지선,김현아,조은,이옥상,임성실,Lee, Ji-Sun,Kim, Hyun-Ah,Cho, Eun,Lee, Ok-Sang,Lim, Sung-Cil 대한약학회 2011 약학회지 Vol.55 No.4

Standard combination chemotherapy including isoniazid, rifampin, pyrazinamide, and ethambutol is very effective against tuberculosis. But, these medicines can cause hepatotoxicity which is the main reason for treatment interruption or change in drug regimen. In order to identify risk factors associated with hepatotoxcity in Koreans and assess elevated baseline LFTs' contributions to hepatotoxicity, a retrospective case control study was performed. The medical records of 277 patients who diagnosed with tuberculosis at a community hospital from January 1st, 2007 to June 30th, 2010 were reviewed. Patients were categorized into 3 groups (non toxic group, patients without increase in LFT levels; mild to moderate hepatotoxic group and severe hepatotoxic group). And the correlation between risk factors and hepatotoxicity was analyzed by using SPSS program. The overall incidence of hepatotoxicity was 18% and 8.7% of patients developed severe toxicity. Patients in the severe toxic group had the longest treatment period among the three groups. In 75% of severe toxic group, hepatotoxicity occurred within 18.3 days after starting medication. Hypoalbuminemia (serum albumin <3 g/dl) was a significant risk factor for development of severe toxicity. Elevated baseline transaminase (except ALT), total bilirubin, and preexisting hepatitis were also risk factors which were more than twice as likely to increase risk of severe hepatotoxicity (p>0.05). In conclusion, hypoalbuminemia (serum albumin level <3 g/dl) was a significant risk factor for anti-tuberculosis druginduced severe toxicity. Therefore, before starting antituberculosis chemotherapy, serum albumin level should be assessed at baseline. In high-risk patients (hypoalbuminemia, elevated LFTs) for hepatotoxicty, liver function should be closely monitored up to at least 21 days after taking medication.

사업용 화물자동차의 교통사고 예방체계 강화방안 연구

이지선,정승주,허진수,이창섭,Lee, Ji-Seon,Jeong, Seung-Ju,Heo, Jin-Su,Lee, Chang-Seop 대한교통학회 2016 교통 기술과 정책 Vol.13 No.3

LBL법에 의해 TiO₂막이 코팅된 광촉매 글라스 비드 제조

이지선,채유진,이미재,김세기,황종희,임태영,현승균,김진호,Lee, Ji-Sun,Chae, Yoo-Jin,Lee, Mi-Jai,Kim, Sei-Ki,Hwang, Jong-Hee,Lim, Tae-Young,Hyun, Soong-Keun,Kim, Jin-Ho 한국재료학회 2012 한국재료학회지 Vol.22 No.7

$TiO_2$ thin films consisting of positively charged poly(diallyldimethylammonium chloride)(PDDA) and negatively charged titanium(IV) bis(ammonium lactato) dihydroxide(TALH) were successfully fabricated on glass beads by a layer-by-layer(LBL) self-assembly method. The glass beads used here showed a positive charge in an acid range and negative charge in an alkaline range. The glass beads coated with the coating sequence of(PDDA/TALH)n showed a change in the surface morphology as a function of the number of bilayers. When the number of bilayers(n) of the(PDDA/TALH) thin film was 20, Ti element was observed on the surface of the coated glass beads. The thin films coated onto the glass beads had a main peak of the (101) crystal face and were highly crystallized with XRD diffraction peaks of anatase-type $TiO_2$ according to an XRD analysis. In addition, the $TiO_2$ thin films showed photocatalytic properties such that they could decompose a methyl orange solution under illumination with UV light. As the number of bilayers of the(PDDA/TALH) thin film increased, the photocatalytic property of the $TiO_2$-coated glass beads increased with the increase in the thin film thickness. The surface morphologies and optical properties of glass beads coated with $TiO_2$ thin films with different coating numbers were measured by field emission scanning electron microscopy(FE-SEM), X-ray diffraction(XRD) and by UV-Vis spectrophotometry(UV-vis).

사암계 석탄폐석을 활용한 E-glass fiber 조성의 유리 제조 및 특성

이지선,임태영,이미재,황종희,김진호,현승균,Lee, Ji-Sun,Lim, Tae-Young,Lee, Mi-Jai,Hwang, Jonghee,Kim, Jin-Ho,Hyun, Soong-Keun 한국결정성장학회 2013 韓國結晶成長學會誌 Vol.23 No.4

삼척도계지역의 탄광에서 석탄채굴시에 부산물로 발생되는 사암계 석탄폐석을 원료로 사용하여 E-glass fiber 조성의 유리를 제조하였다. 본 연구에서는 카본함량이 비교적 적은 실리카-알루미나질의 사암계 석탄폐석을 사용하였으며, 폐석의 투입량을 0~35 %까지 변화시켰다. 서로 다른 석탄폐석 투입량을 갖는 배치원료를 $1550^{\circ}C$에서 2시간 용융하여 E-glass조성을 갖는 투명하고 맑은 유리가 얻어졌고, 81~84 %의 높은 가시광투과율, $5.39{\sim}5.61{\times}10^{-6}/^{\circ}C$의 열팽창계수, 851~$860^{\circ}C$의 연화점을 나타내었다. 유리섬유 시편은 $1150^{\circ}C$에서 섬유인상장치를 통해 얻어졌고, 복합재료의 보강용 유리섬유로서 내화학성 시험과 기계적 특성평가를 위한 인장강도를 측정하였다. 그 결과 석탄폐석을 사용한 E-glass fiber의 특성이 석탄폐석을 사용하지 않은 보통 E-glass 섬유에 비해 충분히 양호한 특성을 나타내어 E-glass 섬유용 원료로서 석탄폐석의 활용가능성을 확인할 수 있었다. The glass of E-glass fiber composition was fabricated by using refused coal ore which is obtained as by-product from Dogye coal mine in Samcheok. We used silica-alumina refused coal ore which has low carbon content relatively, and the amount of refused coal ore has been changed from 0 to 35 % in batch composition. E-glass was fabricated by the melting of mixed batch materials at $1550^{\circ}C$ for 2 hrs with different refused coal ore composition of 0~35 %. We obtained a transparent and clear glass with high visible light transmittance value of 81~84%, thermal expansion coefficient of $5.39{\sim}5.61{\times}10^{-6}/^{\circ}C$ and softening point of $851{\sim}860^{\circ}C$. The glass fiber samples were also obtained through fiberizing equipment at $1150^{\circ}C$, and tested chemical resistance and tensile strength to evaluate the mechanical property as a reinforced glass fiber of composite material. As the result, we identified the properties of E-glass fiber by using refused coal ore are plenty good enough compare to that of normal E-glass without refused coal ore, and confirmed the possibility of refused coal ore as for the raw material of E-glass fiber.

단신;1,2,3,4-Tetrahydroisoquinoline 유도체의 합성

이지선,이채호,Lee, Ji Sun,Lee, Chai Ho 대한화학회 2001 대한화학회지 Vol.45 No.1