외상성(外傷性) 기관지(氣管支) 파열(破裂) - 1례(例) 보고(報告) -

이종국,이성구,이성행,Lee, Chong Kook,Lee, Sung Koo,Lee, Sung Haing 대한흉부심장혈관외과학회 1976 Journal of Chest Surgery (J Chest Surg) Vol.9 No.1

Rupture of a bronchus is an unusual result of nonpenetrating trauma to the chest. This case was a 19 year old male who was a worker in the mine. The patient had sustained a compression chest injury without external wound or rib fracture. At five days after trauma, he was suffered from dyspnea and the symptom was progressively increased. Two weeks after the chest trauma, a diagnosis of left main bronchial obstruction due to traumatic bronchial rupture was made by means of bronchoscopy and bronchography. He was operated upon. The left lung was completely atelectatic and the left main bronchus was found to be transected at the level of 3cm from carina. End-to-end anastomosis of the bronchus was performed and the left lung was aerated very well. postoperative course was uneventful.

기관(氣管) 섬유종(纖維腫)의 1례(例)

이종국,이성구,이성행,Lee, Chong Kook,Lee, Sung Koo,Lee, Sung Haing 대한흉부심장혈관외과학회 1976 Journal of Chest Surgery (J Chest Surg) Vol.9 No.1

Primary tumors of trachea are rather uncommon, and few cases of direct surgical excision were reported in the literature. Recently we had the opportunity to see a patient with a benign obstructing tumor of the trachea which was confirmed as fibroma. The patient has complained of intermittent dyspnea, especially during inspiratory phase, dry cough and wheezing of a strident character for last 8 years. Bronchoscopy or bronchography were not attempted because of severe dyspnea. Trachea tomogram revealed oval mass at the terminal trachea. The right posterolateral thoracotomy was performed. Tumor, $2.5{\times}1.7cm$ in size, was located at terminal trachea and removed through right lateral tracheotomy without difficulty. Postoperatively all the symptoms and signs disappeared.

상압소결 $\beta$-SiC에 있어서 표면부에서의 액상집중과 미세구조의 변화

이종국,양권승,김환,Lee, Jong-Kook,Yang, Gwon-Seung,Kim, Hwan 한국세라믹학회 1996 한국세라믹학회지 Vol.33 No.8

The liquid-phase concentration from the interior to the surface region and its influence on the microstructural changes were investigated in pressureless sintered $\beta$-SiC Surface reaction-layer was formed by reaction of packing powder and volatile components on the surface during sintering which was induced the concentration of liquid-phase in the surface regions. The microstructural changes between the surface region and the interior were appeared in sintered specimen which was resulted from the difference of liquid-phase content during sintering. Microstructural changes were observd with the depth of about 250${\mu}{\textrm}{m}$ from he surface. The grain size and aspect ratio of SiC in the interior are larger than those in the surface region and the rate of transforma-tion of $\beta$-to $\alpha$-SiC during sintering is higher in the interior than that in the surface region.

콜로이드 Ag 나노입자 합성시 계면활성제의 영향

이종국,최남규,서동석,Lee Jong-Kook,Choi Nam-Kyu,Seo Dong-Seok 한국재료학회 2005 한국재료학회지 Vol.15 No.5

Silver nanoparticles were synthesized by chemical reduction method from aqueous silver nitrate solution ana hydrazine as a reduction agent. The morphology, particle size and shape were dependent on the mixing method, reaction temperature and time, molar ratio of hydrazine and silver nitrate, the kind of surfactant, and the addition of surfactant. The stability of the colloidal silver was achieved by the adsorption of surfactant molecules onto the particle. Silver nanoparticles have a characteristic absorption maximum at 430 nm under UV irradiation. It was found that the colloid was nanometer m size and formed very stable dispersion of silver. The Ag nanoparticles obtained showed the spherical shape with the size range of 10-30 nm.

소 뼈로부터 제조한 다공형 하이드록시아파타이트 세라믹스의 생체친화 특성

이종국,고영화,이난희,Lee, Jong-Kook,Ko, Young-Hwa,Lee, Nan-Hee 한국결정성장학회 2012 한국결정성장학회지 Vol.22 No.3

소뼈를 하소하여 천연 하이드록시아파타이트 분말을 얻은 다음, $1100^{\circ}C$ 및 $1200^{\circ}C$로 상압 소결하여 기공율이 각각 35 % 및 18 %인 다공성 하이드록시아파타이트를 제조한 후 이들 시편의 생체친화성을 평가하였다. 골아세포의 성장속도과 세포독성의 유무에 따라 평가되는 생체친화성은 MG-63 세포의 부착능과 분화되어 증식되는 세포의 수로 측정하였다. in vitro에서 세포 반응을 관찰한 결과 소뼈로부터 제조된 하이드록시아파타이트 시편은 독성이 없고 생체 친화성이 좋은 시편이었다. 세포배양 1일 후부터 하이드록시아파타이트 표면에 세포가 부착되었고, 세포배양 후 3일 후에는 핵 주위로 세포질이 퍼져나갔으며, 5일 후에는 부착된 세포의 수가 크게 증가하였다. 배양 초기에는 밀도에 관계 없이 세포의 부착능이 유사하였지만, 세포 배양 시간이 증가하면서 기공율이 높은 시편에서 세포의 부착 및 성장이 더 활발하게 진행되었다. Natural hydroxyapatite powder was obtained from the calcination of bovine bones and its porous compacts were fabricated by pressureless sintering at 1100 and $1200^{\circ}C$ for 1h. To evaluate and compare their biocompatibility with porosity, we investigated the support of osteoblast cells growth and cytotoxicity using the MG-63 cell line model in vitro. Sintered hydroxyapatite ceramics have a porous microstructure with a relative density of 65 % at $1100^{\circ}C$ and 82 % at $1200^{\circ}C$. Cells adherence to the surface of hydroxyapatite ceramics was observed in a day after the cell culture, and the spreading of cytoplasm around the nucleus was shown after 3 day cell culture. Most of cells were extended to the surface of hydroxyapatite through the wide area. Cell viability was nearly the same till 3 days culturing. But the rate of cell growth is higher in the specimen sintered at $1100^{\circ}C$ than that of $1200^{\circ}C$. It indicates that the porosity is an important factor to enhance the cell viability in the porous hydroxyapatite ceramics derived from bovine bones.

사용자탐방-(주)첨성대 이완호 사장

이종국,Lee, Jong-Guk 한국과학기술정보연구원 2000 지식정보인프라 Vol.2 No.-

슈퍼컴퓨터의 벤치마크 시험용으로 자주 이용되던 기상예측, 이제 공공기관이 아닌 민간업체가 나서고 있다. 슈퍼컴퓨터를 비롯한 정보기술의 발달과 더불어 고부가가치 자원으로 부각되고 있는 기상정보를 가공하여 실시간 웹 서비스를 제공하는 (주)첨성대 이완호 사장을 만나보았다.

CeO$_2$ 도핑에 의한 불규칙 입자형상의 이트리아 안정화 지르코니아 제조

이종국,강현희,김영정,김환,Lee, Jong-Kook,Kang, Hyun-Hee,Kim, Young-J.,Kim, Hwan 한국세라믹학회 1998 한국세라믹학회지 Vol.35 No.12

Yttria-stabilized zirconia ceramics with irregular grain shapes and curved grain boundaries was prepared by ceria doping. The amount of ceria doped into zirconia compacts by a dipping method were at range of 2 to 20 mol% Irregular grain shapes and curved grain boundaries were formed only inspecimens doped with more than 8mol% cerial. Ceria-doped specimens showed large grain size and low sintered density compared with pure yttria-stabilized zirconia which was due to the increase in the contents of stabilizer and cubic phase. The amount of doped ceria was larger on the surface than the inside regions and therefore mi-crostructure and phase on the surface were different from those in the inside regions. Transgranular frac-ture mode was observed ion ceria doped specimens due to irregular large grain sizes.

침투형 집수정의 우수유출 저감효과 분석을 위한 실시간 계측

이종국,허정호,박상구,Lee, Jong-Guk,Heo, Jeong-Ho,Park, Sang-Gu 한국수자원학회 2000 한국수자원학회논문집 Vol.33 No.1

모싯잎의 육성 계통별 성분 함량, 항산화 및 ACE 저해 활성

이종국,이정,조희제,윤혜경,김명석,Lee, Jong-Kug,Lee, Jeong,Cho, Hui-Je,Yoon, Hye-Kyung,Kim, Myung-Seok 한국식품영양학회 2018 韓國食品營養學會誌 Vol.31 No.2

Ramie (Boehmeria nivea M.) has been used for fiber materials in Korea traditionally, but in recent years, the concern with ramie leaves for the food industry such as tteok (a kind of Korean rice cake) industry has been increasing, so a study for eatable ramie is required for the expansion of ramie consumption. Moreover, the ramie varieties for the food industry are not established, so the natural species are cultivated in general; therefore, it is very important to select the ramie varieties for the food industry such as rice cakes, tea, beverage and so on. This study was undertaken to compare the physiochemical properties among 9 ramie lines selected in the Yeonggwang-gun Agricultural Technology Center to select the eatable ramie varieties for the food industry. The contents of the protein among 9 ramie lines was 6.21~7.56% and had the highest content in the YG55. The folic acid (folate) and vitamin C content had varying differences among the 9 lines; the content of folate showed $771.52{\sim}1,978.84{\mu}g%$, that of vitamin C showed 149.42~275.34 mg%. The ACE inhibitory activity appeared to be the highest in YG88 (21.5%) among the 9 ramie varieties tested.

Yttria를 도핑한 세리아 안정화 지르코니아 세라믹스의 미세구조

이종국,강현희,서동석,이은구,김환,Lee, J.K.,Kang, H.H.,Seo, D.S.,Lee, E.G.,Kim, H. 한국재료학회 1999 한국재료학회지 Vol.9 No.8

세리아 안정화 지르코니아 성형체내에 이트리아를 침적법으로 도핑시켜 미세구조를 관철하였다. 도핑된 이트리아의 양과 열처리 조건을 제어하여 입계가 변형된 불규칙 입자형상의 미세구조를 형성시켰으며, 이때 입자형상의 불규칙 정도는 첨가된 이트리아의 양에 비례하였다. 0.2M 농도의 Y(NO$_3$)$_3$.6$H_2O$의 수용액에 재침적하여 1$650^{\circ}C$에서 2시간 열처리한 시편의 미세구조는 표면부와 내부 모두에서 불규칙 입자형상을 나타내었으며, 입자의 불규칙도도 가장 큰 것으로 나타났다. 가압소결을 행한 결과 입계가 불규칙하게 변화된 미세구조가 창출됨과 동시에 평균입자 크기가 0.3$\mu\textrm{m}$ 가량인 미세한 소결체를 제조할 수 있었으며, 상분석 결과 대부분 정방정상을 유지하고 있었다. 불규칙 입자형상의 미세구조를 가진 시편의 파괴인성값은, 정상적인 입자형상을 갖는 시편에서의 압흔 균열 크기로부터 비교 유추한 결과 17.6MPa.m(sup)1/2 이상인 것으로 나타났다. Yttia-doped ceria-stabilized ziconia polycrystals(Ce-TZP) was prepared by dipping method and its microstructure was investigated. By controlling doped-yttria content and annealing condition, yttria-doped Ce-TZP showed the microstructure with irregular grain shape and undulated grain boundary. Irregularity of grain shape increased with the amount of yttria doped, and severe undulated grain boundary was observed mainly at the surface region. In the case of yttria-doped Ce-TZP annealed at 1$650^{\circ}C$ for 2h after two dipping times into yttrium nitrate solution of 0.2M, it showed irregular grain shape both at the surface and at the interior region as well as the most severe irregularity. Hot pressed specimen had mean grain size of 0.3$\mu\textrm{m}$ and undulated grain boundary. All specimens with irregular grain shape were retained the tetragonal phase. The fracture toughness of yttria-doped Ce-TZP with irregular grain shape was over the value of 17.6MPa.m(sup)1/2.