광중합형 글라스 아이오노머 시멘트의 개발에 관한 연구

김철위,윤수한,임범순 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.1

The object of this study was to synthesize the experimental light-activated glass ionomer cement change of glass components such as aluminum, fluorine, calcium, and strontium. To reinforce the glass ionomer cement, additions of metallic powder, ceramic powder, and light-activated composite resin to glass ionomer cements were performed. Radiopacity, comprehensive strength, bond strength, fracture toughness, sloubility, and cytotoxicity of the various experimental glass ionomer cements were investigated. From the experiment, the following results were obtained: 1. Experimental light-activated glass ionomer cement showed similar physical and mechanical properties to commercial glass ionomer cement. Radiopacity, resistance of solubility, fracture thoughness, and compressive strength of the experimental cement were superior to those of commercial cements, but bond strength and biocompatibility of the experimental cement were inferior to commercial cements. 2. Addition of amalgam powder to light-activated glass ionomer cement resulted in the lower compressive strength and fracture toughness, but addition of aluminium powder resulted in the enhanced the fracture toughness. 3. Addition of alumina powder (Al₂O₃) could enhance the compressive strength and fracture toughness of the glass ionomer cement without sacrificing of the esthetic property. 4. Physical mixing light-activated glass ionomer cement with light-activated composite resin could enhanced the physical properties except for bond strength.

유방암과 섬유선종의 방사선학적 소견 : 유방 단순촬영술과 유방 초음파검사 소견의 비교 연구 Studies on mammographic and ultrasonographic findings evaluation

임한혁,최득린,고은석,이혜경,임철완,이상진,홍현숙,최교창,김영화,박재성 순천향의학연구소 1997 Journal of Soonchunhyang Medical Science Vol.3 No.2

Purpose : To evaluate the utility of mammography and ultrasonography in study of morphologic differential diagnosis between malignant and benign mass. Materials and Methods : Average age of patients with breast cancer was 48.4 year-old, and that of fibroadenoma was 29.4 year-old. The equipments used for examination were MF-159 high frequency mammography(Bennet Co.) and Acoustic image 5200S. We evaluated mammographic findings about breast parenchymal pattern, calcification, margin and size of the mass associated tumor nature, and ultrasonographic findings about shape, height and width, internal homogenicity and echo pattern, wall contour, boundary echo, and posterior shadow in breast mass. Thirty-seven of mammographic findings and 34 cases of ultrasonogreaphic findings in pathologically proven breast cancer and 34 case of mammographic findings and 71 cases of ultrasonographic findings in breast fibroadenoma were reviewed retrospectively. Results : In mammographic study, the parenchymal patterns of breast cancer according to Wolfe classification were NI(16.2%), PI(24.3%), P@(37.8%), and DY(21.6%) and those in fibroadenoma were NI(3.1%), Pl(11.7%), P2(35.2%),and DY(50%). Mammographic findings about presence of calcification were as follows; only calcification(16.2%), only mass(51.3%), and mass with calcification(32.5%) in breast cancer, and only mass(91.2%), mass with calcification(8.8%) in fibroadenoma. The features of mass margins were classified as ill-defined margin(45.9%), well-defined(5.4%), and well-defined with partial spiculation(48.6%) in breast cancer and ill-defined(20.5%), well-defined(73.5%), and well-defined with partial spiculation(5.8%) in fibroadenoma. The mass were grouped by size; 1-2cm(37.8%), 2-4cm(45.9%), and 4-6cm(16.3%) in breast cancer and 1-2cm(79.4%), 2-4cm(17.6%), and 4-6cm (3.0%) in fibroadenoma. On ultrasonographic study, the shape of masses in breast cancer were lobulated(82.3%),oval(14.7%), and round(3.0%),and those in fibroadenoma were lobulated(14.0%), oval(57.7%), and round(18.3%). The cases that the height was longer than width were 32.3% in breast cancer and 0% in fibroadenoma. The findings about homogenecity and echo patterns were as follows; hypoechoic(52.9%) and mixed(47.1%) in breast cancer and hypoechoic(2.8%), hypoechoic(63.4%), and mixed(33.8%) in fibroadenoma. The margin of masses were smooth in 85.9% of fibroadenoma, and irregular in 73.6% of breast cancer. The boundary echoes of masses and decreased posterior echo shadow were seen only in 61.8% and 55.9% of breast cancer, respectively. Conclusion: The margin and calcifications are more clearly delineated on mammography but breast cancer and fibroadenoma, both are more commonly developed in dense parenchymal pattern(P2+DY),and there findings are easily obscured in mammography. So ultrasoography is very useful in these masses evaluation, especially amoung young patients.

SD Rats를 이용 1-hexene의 흡입독성 연구

김현영,임철홍,정용현,이권섭,이성배,이준연,한정희,전윤석,이용묵 한국환경독성학회 2001 환경독성보건학회지 Vol.16 No.4

The purpose of this study was to investigate the acute (4 hours) and repeated-dose (6 hours a day, 5 days a week, 4 weeks) toxic effects of I -hexene on Sprague- Dawley (SD) rats which were treated by inhalation. The results were as follows; I. The median lethal concentration (LC_(50)) was estimated 52,694 ppm (confidence limit 95%; 49,494~55,447 ppm) in acute inhalation. Abnormal clinical signs related to the l-Hexene were not observed with the acute inhalation dose. Gross findings of necropsy revealed on evidence of specific toxicity related to the 1-hexene, II. By repeated inhalation exposure the body weight of male were more or less reduced by the dose of 2,500 ppm and 5,000 ppm compared with control group. However there were no significant variation hematology and blood biochemistry for the exposed rats compared with the control rats. Abnormal clinical signs and gross findings of necropsy related to the 1-hexene were not shown. In conclusion when we exposed I-hexene to SD rats for 4 weeks, 5 days per week, 6 hours per day, the Lowest observed effect level (LOEL) was over 2,500 ppm and Non observed effect level (NOEL) was below 500 ppm.

크롬(Ⅵ)의 체내 흡수와 소실속도에 관한 연구

김현영,이성배,임철홍,이권섭,정용현,이종성,한정희,전윤석,황호순,이용묵 한국산업위생학회 2003 한국산업보건학회지 Vol.13 No.1

The CrO3 mostly used in plating. metal surface disposal, leather, cosmetic manufacturing, as an experiment material by repeatedly inhaling and exposure the male S.D. rats at a 0.00, 0.2., 0.50, 1.25 mg/㎡ concentration(particle size: 0.5-0.5 aerosol)6hours a day, 5day a week in 13weeks comparing with 2weeks, 8weeks of recovery group about the noxiousness of the experiment animal and the reduce scale of the CrO3 in the internal organ especially in blook and respiratory organ with the period of convalescent and clearance. The experiment results which we received are as follows. 1. In blood the RBC, HGB and HCT experiment, rats with 0.20, 0.50 mg/㎡ concentration showed that there were some decreases but not dependent. The kidneys absolute weight compared with control group was reduced intentionally(p〈0.05) and the lungs absolute weight compared with control group showed intentional increase(p〉0.05). 2. After the exposure of the experiment material, the whole blook, l\blood plasma and red blood cell in blood by (x): the period of convalescent, per (y); the decreasing of Cr concentration, was y=66.51 e -0.057x, y=67.2 e-0.101x, y=70.01 e-0.030 in 0.50 mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life (day)was estimated 12.0, 6086, 23.0 each. 3, After the exposure of the experiment material, the experiment animals lung, liver and kidneys by(x); the period of convalescent, per (y); the decreasing of Cr conentration, was y=1808 e-0.00493x, y=12.02e-0.0297x, y=67.61 e-0.0292x in 0.50mg/㎡ exposure concentration by calculating the clearance coefficient of correlation, and the half life(day)was estimated 140.6, 23.3, 23.7, each, and including lung, liver with all of the experiment internal organs, the Cr clearance decreased as the exposure concentration increased.

S.D. Rats를 이용 1, 1-Dichloro-1-fluoroethane의 아민성 흡입독성 연구

김현영,이성배,임철홍,김철우,점용현,한정희,전윤석,최수영,강대봉,이용묵 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.1

There were no specific effects for test materials on Sprague-Dawley (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body l, l-Dichloro-1 -fluoroethane (used as coolant, metal cleaner and solvents) exposure(0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations, there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration. Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-l -fluoroethene inhalation was evaluated in groups with 3,000 ppm below (S .D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-l-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure .

Aortocaval Fistula by Luetic Abdominal Aortic Aneurysm : Report of a case

Lim, Sang Hyun,Lee, Cheol Joo,Roh,Hwan-Kyu,Kim, Dae Jun,Han, Jung Sun,Shin, Joon Han,Kim, Han Soo 아주대학교 1996 아주의학 Vol.1 No.2

A 53-year-old male patient was operated on because of a spontaneous abdominal aortic aneurysm with aortocaval fistula. The fistula was successfully closed and bifurcated woven Dacron graft was used to replace the aneurysm. The patient had with characteristic signs and symptoms of aortic aneurysm with arteriovenous fistula. Proper diagnosis and prompt surgical repair of aortocaval fistula saved the patient. The use of rapid infusion system provided stable hemodynamics during the operation.

제주 화산회토양의 중금속 연속추출 특성 및 작물 흡수에 미치는 영향

임한철(Han-Cheol Lim),문경환(Kyung-Hwan Moon),전승종(Seung-Jong Jeon),박원표(Won-Pyo Park),현해남(Hae-Nam Hyun) 한국토양비료학회 2009 한국토양비료학회지 Vol.42 No.2

이 시험은 제주도 화산회토양을 이용하여 Ni, Cu,Zn의 토양중 존재형태를 알아보고 토양 중금속이 청경채의 흡수에 미치는 영향을 알아보고자 수행되었다. 토양 중 함량을 연속추출법에 의해 알아본 결과 토양 종류마다 각 중금속의 존재형태가 차이가 있었고, 이를 이용하여 토양 종류를 구분할 수 있었다. 중금속 함량이 다른 토양을 이용하여 청경채를 재배했을 경우 Zn, Cu는 뿌리에서 흡수되어 지상부로 이동되었으나 Ni은 지상부에서 거의 검출이 되지 않아 청경채 내에서 미량원소의 이동성이 달랐다. 그러나 토양 중 함량과 청경채의 함량 간에는 치환성 Zn을 제외하고는 상관관계가 없었으며, 특히 Ni은 식물체 내에서 이동도 어려울 뿐만 아니라 토양 중 함량과 상관관계를 내기도 어렵기 때문에 전함량이나 치환성함 량 등 지금까지의 방법에 의한 토양 중 함량으로 식물체의 함량을 추정하기에는 매우 어렵다고 판단되므로 새로운 접근방법이 개발될 필요가 있다고 판단된다. 인체의 중금속 흡수에 의한 위해성 평가와 관련해서는 토양 식물체, 식물체 인체 두 단계를 거치게 되는데 각 단계에서 불확실성이 존재하므로 중금속의 기준을 토양 및 식물체 별로 각각 마련하는 것보다는 식물체내 농도만으로 정하는 것도 한가지 해결책이 될 수 있다고 생각한다. We studied to compare the fractionation patterns of Ni, Cu, Zn in Jeju volcanic ash soils and to elucidate the uptakes of them by Pakchoi(Brassica campestris var. chinensis). Fractionation patterns of soils by sequential extraction method were different and make to distinguish from various soil types. In Pakchoi, the transfer rates of Ni, Cu, Zn from root to shoot were also different by metal types. There are low corelation between fractional contents in soil and contents in plants of trace elements except for exchangeable Zn. It is needed to develop novel methods for the assessment soil Ni in relation to plant uptake because of poor corelation.

제주도 토양 종류 및 경지이용 특성에 따른 Ni, Cu 및 Zn 함량 변화

임한철 ( Han Cheol Lim ),문경환 ( Kyung Hwan Moon ),김계훈 ( Kye Hoon Kim ),장공만 ( Gong Man Jang ),장규성 ( Kyu Sung Jang ),현해남 ( Hae Nam Hyun ) 한국토양비료학회 2007 한국토양비료학회 학술발표회 Vol.2007 No.1

급결제의 인젝터 주입이 고유동 모르타르의 거푸집 누출량 저감 가능성 분석

임군수 ( Lim Gun-su ),한준희 ( Han Jun-hui ),현승용 ( Hyun Seung-yong ),김종 ( Kim Jong ),한민철 ( Han Min-cheol ),한천구 ( Han Cheon-goo ) 한국건축시공학회 2022 한국건축시공학회 학술발표대회 논문집 Vol.22 No.2

High fluidity concrete has excellent workability, and if the cross-section of the building is complicated, it is possible to place good quality concrete and increase the construction speed, so its utility value is very high. However, it is premised on the accuracy of concrete formwork assembly. Concrete leakage through formwork gaps is an important consideration when applying high flow concrete. In order to quickly solve the leak of high fluidity concrete caused by formwork gap occurring at the site by accelerator injection, we proceeded with research to confirm the possibility of reducing the amount of formwork leakage of high fluidity mortar. It was confirmed that the injection of the accelerator could reduce the amount of mortar leakage.

앙상블 학습을 이용한 콘크리트의 압축강도 예측

한준희(Han, Jun Hui),임군수(Lim, Gun Su),한수환(Han, Soo Hwan),백성진(Beak Sung Jin),김종(Kim, Jong),한민철(Han, Min Cheol) 한국콘크리트학회 2022 한국콘크리트학회 학술대회 논문집 Vol.34 No.1