표면중합을 이용한 초발수 복합입자의 제조 및 표면특성 : 중합시간의 영향 The Effect of Polymerization Time

범정철,하종욱,박인준,김정훈,이수복,ShiYuan, Cheng 한국공업화학회 2003 응용화학 Vol.7 No.2

This study investigates the preparation of poly(perfluoroalkyl acrylate)[PTA]/silica composite particles by surface polymerization and their characteristics according to surface polymerization time. The particles were prepared by "grafting-from" technique by immobilizing self-assembled initiator and surface radical polymerization from silica particle surface. Characterization was done by contact angle and sliding angle measurements, surface roughness measurement and surface free energy estimation Contact angle were inversely proportion to sliding angle. Graft density(GD) and contact angle of composites increased according to polymerization time. On the other hand, surface free energy and sliding angle were decreased according to increment of polymerization time.

Poly(perfluoroalkyl acrylate)/Silica 나노복합체의 표면이행성 연구

범정철,하종욱,이광원,박인준,소원욱,이수복 한국공업화학회 2003 응용화학 Vol.7 No.2

Surface migration of Poly(perfluoroalkylethyl acrylate)(PFA)/silica nanocomposites added in poly(methylmethacrylate()(PMMA) was investigated by comparing before and after annealing. In this study, surface migration characterizations of PFA/silica composites were measured by SEM(Scanning Electron Microscopy) and contact angle measurement. Their surface free energies were calculated with contact angle data by geometric mean approximation. The contact angles were increased and the surface free energies were decreased, according to increasing the graft density of nanocomposites and decreasing the concentration of PMMA, respectively. It was confirmed that PFA/silica nanocomposites were successfully migrated toward the surface of the PMMA film.

통계적 실험계획에 의한 PECVD로 증착된 실리콘 산화막의 특성 분석

李晟準,金洸範,崔鑛泉,漢秀一,尹知原,金劉邏,朴宰賢,洪尙眞 명지대학교 산업기술연구소 2006 産業技術硏究所論文集 Vol.25 No.-

According as the current needs of low temperature in semiconductor manufacturing process, PECVD using low temperature and high deposition rate is becoming more of a concern. However, PECVD equipment has the defect possibility on the interface between substrates and gate oxide layer, because ions or electrons with much high energy clash the interface. In this study, we embarked on the experiment with Statistical Design of Experiment and then also analyze which parameters influence on the characteristic of silicon dioxide filems. We finally made a constructive proposal for process optimization conditions.

가와사끼 질환에서 감마글로불린의 대량 정주 용법의 효과에 관한 연구

이경희,하태선,박범수,한헌석,하성훈 충북대학교 의과대학 충북대학교 의학연구소 1994 忠北醫大學術誌 Vol.4 No.1

가와사끼병으로 진단받고 고용량의 감마글로불린(2 gm/㎏)을 정맥주사 받은 17명의 환아를 대상으로 임상적 효과와 관상동맥의 변화에 미치는 영향을 연구하여 다음의 결과를 얻었다. 1. 대상 환아의 연령은 평균 2.03세로 3개월에서 5세 사이에 분포하였고, 2세 이하가 58.8%를 차지하고 남여의 비는 1.125 : 1이었다. 2. 가와사끼 진단 기준의 6가지 주증상 중 5가지는 전환아에서 나타났으며, 경부 림프선 종창만 64.7%에서 나타났다. 발생 계절은 봄과 겨울에 76.5%의 환아가 발생하였다. 3. 대량의 감마글로불린 주사 직후 평균 11.4시간에 고열이 없어지고 다른 주증상들도 없어지기 시작하였으며, 대부분(82.3%)이 주사후 20시간 이내에는 소실되었다. 주사중 3례(17.6%)에서 오한 및 일시적인 체온의 상승을 보였으나 주사를 중단할 필요는 없었다. 4. 발병 4주 이내에 관상동맥의 확장이 관찰된 경우는 8례(47.1%)였으나, 이들은 모두 경도의 확장이었다. 발병 2개월 후에 시행한 심초음파도에서는 2명(11.7%)에서만 경도의 확장을 보였고, 나머지는 모두 정상으로 회복되어 있었다. 5. 최저 헤모글로빈치, 최대 C-반응성 단백질, 최대 총백혈구수, 최고 적혈구 혈침속도, 혈소판 최고치는, 발병 4주 이내와 2개월 후에 관상 동맥의 변화가 있는 군과 정상인 군 사이에 의미 있는 차이는 없었다. 이상의 결과로 가와사끼병의 치료에 있어서 단일 고용량의 감마글로불린을 정맥주사하는 방법이 심각한 부작용 없이 임상적 증세를 빨리 호전시키며, 관상동맥의 합병증을 줄이는데 효과적임을 알 수 있었다. 따라서 모든 가와사끼병의 급성기에 가능한 빨리 단일 고용량의 감마글로불린을 정맥주사하는 것을 추천한다. The authors studied the effect of single high-dose intravenous gammaglobulin(2 gm/㎏) on the clinical symptoms and coronary artery abnormalities in seventeen Kawasaki patients and obtained the following results. 1. The patients' ages ranged from 3-month to 5-year, with mean age of 2.03-year. The patients under 2-years comprised 58.8%. The ratio of male to female was 1.125. 2. All of the patients showed 6 major diagnostic criteria with one exception of cervical lymphadenopathy(64.7%). The disease occurred mainly spring and winter season(76.5%). 3. Fever subsided within 20 hours' of intravenous gammaglobulin infusion in most of the patients(82.3%) with mean value of 11.4 hours, Transient side effects such as fever and chilling sense, developed in 3 cases(17.6%), but there was no need to quit infusion. 4. Echocardiographically, mild coronary arterial dilation was observed in 8 cases(47.1%) within 4 weeks' of onset. After 2 months' of onset, only 2 cases(11.7%) showed mild dilation. 5. There were no significant difference between coronary arterial dilation group and normal group before 4wk and after 2 mo of onset, in terms of hemoglobin nadir, maximal CRP, maximal WBC count, peak ESR, and peak platelet count. Conclusively, single high dose intravenous gammaglobulin infusion in Kawasaki disease showed effective improvement of clinical symptoms and decrease of coronary arterial abnormality. There fore all the children with Kawasaki disease should be treated with single high-dose intravenous gammaglobulin infusion as soon as possible.

PFA / Silica 유-무기 복합체의 제조 및 표면특성

범정철,하종욱,박인준,이수복 한국공업화학회 2003 응용화학 Vol.7 No.1

Poly(perfluoroalkyl acrylate)(PFA) / silica composites having different silica size were prepared by surface polymerization. In this study, surface characterizations of PFA/silica composites were done by HR-TEM(High Resolution Transmission Microscopy), contact angle measurement, sliding angle measurement, surface roughness measurement, and the relationships between the sliding angle and the contact angle were investigated. In the highly hydrophobic region, the sliding angles of water droplets decreased with increasing contact angle. Their surface free energies were calculated with contact angle data by geometric mean approximation. The composites with super water repellent and sliding could be obtained with contact angle of above 150。and sliding angle of below 10。to water droplets. The ultimate value of surface free energies of the composites reached below ca. ldyn/cm.

들잔디 성숙종자로부터 캘러스배양 및 식물체 재분화에 미치는 몇 가지 요인의 영향

이상훈,김범수,원성혜,조진기,김기용,박근제,성병렬,이효신,이병현 Plant molecular biology and biotechnology research 2004 Plant molecular biology and biotechnology research Vol.2004 No.-

In an effort to optimize tissue culture responses of zoysiagrass (Zoysia japonica Steud.) for genetic transformation, factors affecting callus induction and plant regeneration were investigated. MS medium containing 3 ㎎/L 2,4-D was optimal for embryogenic callus induction from mature seed. The plant regeneration frequency of 73.3% was observed when embryogenic calli induced in this medium were transferred to N6 medium supplemented with 0.1 ㎎/L 2,4-D and 5 ㎎/L BA. Among several basic media, MS and N6 medium were optimal for callus induction and plant regeneration, respectively. Regenerated plants were grown normally when shoots transplanted to the soil. A rapid and efficient plant regeneration system established in this study will be useful for molecular breeding of turfgrass through genetic transformation.

고기능성 미립 실리카 제조

이재장,노범식,김동수,장광택 강원대학교 부설 석재복합신소재 제품연구센터 2000 석재연 논문집 Vol.5 No.-

본 연구에서는 attrition mill을 활용하여 분쇄시 발생하는 오염물질을 방지하고 고분자 유기물질의 첨가로 평균 입도 2-3㎛의 미립 실리카 분체에 가능성을 부여하여 규석 관련 첨단산업용 고부가가치 상품을 개발하고자 하였다. 실험결과 용기 내부의 코팅재에 따른 미립화 효율은 세라믹 > 텅스텐 카바이드 > 스테인레스 > 포리우레탄 > 테프론의 순이었으며 오염방지 효과는 세라믹 > 폴리우레탄 > 텅스텐 카바이드 > 테프론 > 스테인레스의 순이었다. 고분자 유기물질의 첨가에 의해 분쇄효율이 증가하였으며, 첨가제의 일부가 표면에 코팅되어 원관의 백색도 85에서 92까지 상승되었다. 형상 조절 실험 및 백색도 향상 실험결과 첨가에에 의한 분쇄 산물은 원광보다 구형에 가까운 것을 알 수가 있었다. This study focused on manufacture of the high value-added products for a high-technology industry related to silica. The silica fines less than 3㎛ was manufactured using laboratory attrition mills with various coated liner and analysed the pollutions added from the grinding test. Ground particle's shape was investigated by adding polymer. In the grinding test, coated material of cylinder affects size reduction rate by order of ceramic, tungsten carbide, stainless steel, polyurethane, teflon. In contamination tests the coated liner affects in order of stainless steel, teflon, tungsten carbide, polyurethane, ceramic. It was found also that the result of additive test showed an instant effects of grinding and whiteness.

PVAc 라텍스 접착제의 열적 안정성에 대한 고찰

권재범,이내우,설수덕 한국안전학회 2003 한국안전학회지 Vol.18 No.3

Latex polymers are widely used for adhesive, binder, paint etc. Especially the PVAc(Polyvinyl acetate) latex which manufactured by vinyl acetate and vinyl alcohol as protective colloid is a useful environmentally friendly adhesive. To increase useful property of PVAc latex, this study was carried out for checking thermal characteristics and physical condition of PVAc latex by DSC, FT-IR, Pyrolyzer GC-MS. The activation energies of thermal decomposition for 40, 48, 56, 64% solid content of PVAc latex were found as 28.1~36.0kcal/mol by Kissinger's method and 17.2~22.0kcal/mol by DSC method. Actually, reasonable solid content could be consiered as 56% because of activation energy and adhesive characteristics. According to the effect of protective colloid for 4, 10, 15, 20wt%, the activation energy shows same tendency to both method and in case of 15wt% has been found as the highest activation energy. The mechanism of thermal decomposition was mainly estimated by main chain scission, not by side group on FT-IR analysis. Main component of Pyrolyzer GC-MS result were consisted of CH₃COOH, CH₃, H₂O and light gases(CO, CO₂, CH₄ etc).

환경친화적인 무기/유기 Core-Shell의 제조에 관한 연구

설수덕,임재길,임종민,권재범,이내우 한국안전학회 2004 한국안전학회지 Vol.19 No.1

Composite particles using inorganic and organic chemicals were synthesized and the results of those reaction were compared to variation of temperature and agitation speed in presence of CaCO₃ which was adsorbed SDBS. Also the synthesises were optimized according to conversion rate of composite particles. In inorganic/organic core-shell composite particle polymerization, CaCO₃ adsorbed by 0.5wt% surfactant SDBS was prepared initially and then core CaCO₃ was encapsulated by sequential emulsion polymerization using MMA at the addition of APS 3.16X 10^(-3)mo1/L to minimize the coagulated PMMA particle itself during MMA shell polymerization. Encapsulated PMMA on CaCO₃ as inorganic/organic core-shell particles was verified by Fr-IR and DSC analysis. It was found that the CaCO₃ was very well encapsulated by PMMA as shell. The surfaces were distinctly found as spindle shape and broad particle distribution after capsulation.

인지된 신뢰, 위험, 유용성 및 편의성이 전자정부 민원서비스 사용의도에 미치는 영향 : 온라인 민원 안내와 민원 신청 서비스를 중심으로

김범수,이정,김경규 한국정보사회진흥원 2006 정보화정책 Vol.13 No.4

전자정부 민원서비스 혁신 시스템(G4C) 사업을 추진한 대한민국 정부는 현재 4,700 여종의 정보와 서비스를 통합전자민원창구(www.egov.go.kr)를 통하여 제공하고 있다. 이러한 전자정부 대국민 민원서비스를 그 관여도에 따라 단순 정보 제공 등“민원 안내 서비스”와 인터넷을 통한“온라인 민원 신청 및 발급 서비스”등의 두 가지로 크게 분류하고, 각 서비스 별로 정부에 대한 신뢰, 정부 서비스 이용과정에서 인지된 위험, 편의성, 유용성이 전자정부 민원서비스 혁신시스템(G4C)의 사용의도에 미치는 영향을 연구하였다. 인터넷을 사용하는 성인 3,074명을 대상으로 한 설문 조사를 통하여 (1) 관여도가 높은 전자정부 서비스에서만, 정부에 대한 신뢰가 사용의도에 영향을 미치며, (2) 인지된 위험은 서비스 종류에 따라 다양한 수준의 영향력을 보이고, (3) 서비스 이용 의도에 가장 큰 영향을 미치는 변수는 유용성이며, (4) 편의성은 서비스 이용의도에 직접적인 영향을 미치기보다는 유용성을 매개로 하여 간접적으로 미치는 영향이 더 큼을 보였다.