油膜의 衝突 效果에 對한 硏究

河鈺男,洪錫柱,金炳哲 조선대학교 동력자원연구소 1988 動力資源硏究所誌 Vol.10 No.1

Oil Film can not reduce the error in the course of manufacturing process but also soften the sliding contact, so it can increase the efficiency of the machines. In many case of cold rolling there are impacts and the oil film influences on the structure of the surface. In this manner the influences of the oil film under impact on the flates were studied and the following conclusions were obtained; 1) In the case of being oil film and not being oil film, there were differences in the central area of surface. 2) In the case of not being the oil film the structure of the surface was flated and being ol film the structure did not change. 3) When the oil film is broken by the impact the metal begin to contact and when the viscosity is thick, it hard to breaking. 4) The higher the viscosity is the longer the contact the time of metal.

RF Sputtering으로 제작한 SiO₂ 및 SiO₂/TiN 박막의 R-V 특성

김창석,하충기,김병인 조선대학교 에너지.자원신기술연구소 2001 에너지·자원신기술연구소 논문지 Vol.23 No.2

In this study the thin films with the structure of Si+SiO₂and Si+SiO₂+TiN are made by RF sputtering method. TIN, which has small diffusion coefficient and low resistivity, is evaporated between SiO₂and A1 layers. It investigates the V-R characteristics depending on the thickness of SiO₂which is used as insulation layer and researches its effects on voltage stability of thin film and varistor. These films show very small resistance value in negative(-) voltage and large value in positive voltage band, and with the increase of voltage, resistance value is rapidly reduced and the satisfactory characteristic of varistor is shown at +l[V]. It is found that resistance value of TIN thin film is small and also TiN thin film has more current than the thin film which is not evaporated by TIN thin film. When A1 electrode is evaporated on SiO₂thin film, spiking occurs, but the spiking can be prevented with evaporation of TIN between SiO₂and Al layers and this thin film is made easily because of its good attachment. With the increase of the resistance is changed into non-linear pattern and the bidirectional varistor characteristic is shown and then its theory can be verified by this experiment. Accordingly, when TiN is evaporated on Si Wafer(n-100), it obtains better voltage-resistance than thin film which is not evaporated and also when varistor character is used electrically to automatic control element such as elimination of flame, power distribution arrestor and constant voltage compensation, satisfactory reproducibilities are expected.

Diesel-Diglyme 混合燃料가 디젤엔진의 性能에 미치는 影響

문병수,한상덕,하종석,김한덕 충북대학교 산업과학기술연구소 2002 산업과학기술연구 논문집 Vol.16 No.1

While the amount of diesel engine is increasing, the harmful exhaust emission is regarded as one of the main causes of environment pollution. In this study, by using reformulated diesel fuel mixed with the oxygenate Diglyme in various ratios, the effects of the reformulations on engine's output performance and exhaust emission have been shown. The reformulated fuel mixed with oxygenate Diglyme shows an increase in output power while CO and SMOKE were lowered by using the regular diesel fuel. By applying the mixed Diglyme fuel to diesel engine, in general, some reduction of harmful exhaust emission could be achieved without any significant change of the output efficiency of the engine.

자연 방사선량 중 ²²²Rn 기여 성분 정량 해석

이병영,채하석,전재식,오희필,김도성 대한방사선 방어학회 1989 방사선방어학회지 Vol.14 No.2

옥외 라돈이 호흡기관에 주는 선량을 측정·평가할 목적으로 CR-39 비적검출기를 내장한 라돈컵을 사용하여 대기중 라돈농도를 측정하였다. 직접형 검출기 및 개방 컵과 필터 컵의 구조를 갖는 CR-39비적검출기에 대한 라돈검출인자는 공기중의 농도가 잘 알려진 표준라돈 조사시설에서 이들 검출기와 라돈컵을 일정기간 조사하여 결정하였다. CR-39를 70°c, 30% NaOH용액으로 220분간 화학부식하였을 때 직접형 거출기와 개방 컵, 필터 컵에 대한 라돈검출인자는 각각 0.273, 0.0813, 0.0371tr mm-2/37 Bqm-3·d)였다. 또한 1988년 5월에서 1989년 3월까지 대전(충남대학교)에서 측정한 대기중의 라돈농도는 개방 컵에 의한 결과는 27.4 - 135.8Bq/m3(0.74 - 3.67 pCi/l)로서 연평균 73.3 Bq/m3(1.98 pCi/l)이었으며, 필터 컵에 의한 결과는 16.7 - 143.9 Bq/m3(0.45 - 3.89 pCi/l)로 연평균 68.5 Bq/m3(1.85 pCi/)이었다. 측정한 옥외 대기중이 라돈농도와 부위별 폐선량모형으로부터 산출한 ICRP표준인의 호흡기관에 대한 실효 선량당량률은 약 520 nSv/h로 평가되었다. A study for the assessment of dose given by outdoor radon to respiratory system has been carried out by making use of radon-cups containing CR-39 plastic track detectors. Detection efficiencies were determined by irradiation of the radon-cups in a standard radon chamber of known concentration. Thus determined detection factors of CR-39 plastic track detector in bare, open cup and filtered cup geometry are found to be 0.273, 0.0813 and 0.0371 trmm-2/(37 Bqm-3 d), respectively, which are chemically etched in 30% NaOH solution of 70℃ for 220 minutes. The outdoor radon concentrations measured at Taejeon (Chungnam National University) from May 1988 to March 1989 are in the range of 27.4 - 135.8 Bq/m3 (0.74 - 3.67pCi/l) by open cup and 16.7 - 143.9 Bq/m3 (0.45 - 3.89pCi/l) by filtered cup, which yield overall annual average value of outdoor radon concentration of 70.8 Bq/m3 (1.91 pCi/l). Corresponding effective dose equivalent rate to respiratory system of ICRP standard man is assessed to be 520nSv/h.

반도성 BaTiO₃의 PTCR 효과에 미치는 첨가제와 냉각속도의 영향

이경희,최석진,이병하 明知大學校 産業技術硏究所 1988 産業技術硏究所論文集 Vol.7 No.-

In this study, first, we measured the PTCR effects according to the variations of dopant amount (0.1-0.3wt% Sb₂O₃, 0.075-0.175w1% ??) of BaTiO₃specimens, which fired at 1320℃ in 1 hour and cooled 100℃/hr rate. Second. we measured the PTCR effects according to the colling rate (200℃/11r, 100℃/hr, 50℃/11r) of 0.lwt% Sb₂O₃or 0.075wt% ?? doped BaTiO₃ specimens which have the best characteristics. Third, we investigated the PTCR effects and microstructures according to the variations of MnSO₄additive amount (0.0045 - 0.0125wt%) of BaTiO₃, specimens based on the compositions and cooling rate which showed the best characteristics from previous experiments. The results were that the PTCR effects were increased and the grain growths were inhibited as the increased amount of MnSO₄and slowed cooling rate.

CT-26 선암을 접종한 마우스에서 Iodine-131-Iodomisonidazole 의 생체분포 및 종양저산소증의 영상화

Yang, David J,Kim, E Edmund,김혜원,김창근,윤권하,김현정,정선관,노병석,Lee, Hyun-Chul 대한핵의학회 1999 핵의학 분자영상 Vol.33 No.3

urpose: Misonidazole is a radiosensitizer that binds in hypoxic cells. The purpose of this study was to find out the feasibility of I-131-Iodomisonidazole (IMISO) for imaging of tumor hypoxia. Materials and Methods: Tosyl precursor was dissolved in acetonitrile and I-131-NaI was added to synthesize IMISO. Balb/c mice inoculated with CT-26 adenocarcinoma were injected with IMISO. Mice were sacrificed at 1,2,4,24 hr and % of injected dose per gram of tissue (%ID/g) was determined. For scintigraphy and MRI, mouse bearing CT-26 adenocarcinoma was administered with IMISO and imaging was performed 4 hr after. Then, mouse body was fixed and microtomized slice was placed on radiographic film for autoradiography. Results: %ID/g of tumor was 1.64 (1h), 0.98 (2h), 0.85 (4h) and 0.20 (24h), respectively. At 24h, %ID/g of tumor was higher than that of all other tissues except thyroid. Tumor to muscle ratio increased with time and tumor to blood ratio also increased with time and reached 1.53 at 24 hr. On autoradiogram, tumor was well visualized as an increased activity in central hypoxic area of the tumor which corresponds to the area of high signal intensity on T2-weighted MR image. On scintigraphy, tumor uptake was visualized. Conclusion: This results suggest that IMISO may have a potential for tumor hypoxia imaging in mouse model. However, further study is needed to improve it's localization in tumor tissue and to achieve acceptable images of tumor hypoxia.

자연방사선량중 ^222 Rn 기여성분 정량해석

전재식,오희필,채하식,이병영,김도성 충남대학교 기초과학연구소 1989 연구논문집 Vol.9 No.-

옥외 라돈이 호흡기관에 주는 선량을 측정·평가할 목적으로 CR-39 비적검출기를 내장한 라돈 컵을 사용하여 대기중 라돈농도를 측정하였다. 직접형 검출기 및 개방 컵과 필터 컵의 구조를 갖는 CR-39 비적검출기에 대한 라돈검출인자는 공기중의 농도가 잘 알려진 표준라돈 조사시설에서 이들 검출기와 라돈컵을 일정기간 조사하여 결정하였다. CR-39를 70℃, 30% NaOH용액으로 220분간 화학부식하였을 때 직접형 검출기와 개방 컵, 필터 컵에 대한 라돈검출인자는 각각 0.273, 0.0813, 0.0371 tr㎜^-2/(37Bqm^-3·d)였다. 또한 1988년 5월에서 1989년 3월까지 대전(충남대학교)에서 측정한 대기중의 라돈농도는 개방 컵에 의한 결과는 2.74-18.87Bq/㎥(0.07-0.5pCi/ℓ)로서 연평균 8.25Bq/㎥(0.22pCi/ℓ)이었으며, 필터 컵에 의한 결과는 1.67-19.76Bq/㎥(0.05-0.54pCi/ℓ)로 연평균 8.18q/㎥(0.22pCi/ℓ)이었다. 그리고 대기중의 라돈농도에서 ^(220)Rn의 기여성분은 무시할 수 있을 정도인 것으로 판단되었다. 측정한 옥외 대기중의 라돈농도와 부위별 폐선량모형으로부터 ICRP 표준인의 호흡기관에 대한 유효선량당량률은 약 60nSv/h(0.5mSv/y)로 평가되었다. A study for the assesssment of dose given by outdoor radon to respiratory system has been carried out by making use of radon-cups containing CR-39 plastic track detectors. Detection efficiencies were determined by irradiation of the radon-cups in a standard radon chamber of known concentration. Thus determined detection factors of CR-39 plastic track detedtor in bare, open cup and filtered cup geometry are found to be 0.273, 0.0813 and 0.0371tr㎜^-2/(37Bqm^-3·d) respectively, which are chemically etched in 70℃, 30% NaOH for 220 minutes. The outdoor radon concentrations measured at Taejeon(Chungnam National University) from May 1988 to March 1989 are in the range of 2.74-18.8Bq/㎥(0.07-0.51pCi/l) by open cup and 1.67-19.76Bq/㎥(0.05-0.54pCi/l.) by filtered cup. The annual averaged value of the measured outdoor radon concentration is 8.2Bq/㎥(0.22pCi/l). Corresponding effective dose equivalent rate to respiratory system of ICRP standard man is assessed to be 60nSv/h or 0.5mSv/y.

돼지에서 정맥, 근육 그리고 경구 투여시의 enrofloxacin의 약물동태학

윤효인,김무열,박승춘,조준형,박병권,이내경,노상석,장범수,신광순,조명행 충남대학교 수의과대학 동물의과학연구소 1996 動物醫科學硏究誌 Vol.4 No.-

In order to characterize pharmacokinetic profiles according to route of a new enrofloxacin salt form (Enrotil®), it was given to 4 healthy pigs via oral (p.o.), intramuscular (i.m.) or intravenous (i.v.) administrations at a dose rate of 5 ㎎/㎏ body weight. Enrofloxacin (ENFX) in serum was detected by bioassay using E. coli BE1186 as a test organism. The biological elimination half-lives (t_1/2(β)) of ENFX were 6.76±0.99 h (i.v.), 7.16±2.30 h (i.m.) and 11.45±3.90 h (p.o.), Volume of distribution (Vd) of enrofloxacin was 2.20±0.31 L/㎏ (i.v.), 2.52±0.60 L/㎏ (i.m.) and 1.88±0.33 L/㎏ (i.m.). Mean residence time (MRT) was 8.77±1.26 h after i.v. injection and the maximal concentration time (Tmax) following p.o. and i.m. administration was 0.76±0.09 h and 0.60±0.12 h, indicating a rapid absorption from these routes. Bioavailibility (F) was calculated as 64.1% for p.o. administration and 59.71% for i.m. injections. In summary, the newly formulated enrofloxacin salt form has shown a high water solubility, rapid absorption and large tissue distribution, suggesting a potential antibacterials for oral application on a large scale in veterinary sectors.

골다공증성 대퇴골 골절의 위험인자 평가

정선관,박성훈,김혜원,이영환,윤권하,최시성,노병석,원종진 圓光大學校 醫科學硏究所 2007 圓光醫科學 Vol.22 No.1

Control of CNTs density through Co deposition time via PECVD

Byung ho Ha,In wha Lee,Yong suk Shin,Hyun suk Kim,Semg yerl Park,Young Jin Lee,Yun hee Kim,Ji hoon Yang,Chong yoon Park 한국진공학회 2003 한국진공학회 학술발표회초록집 Vol.- No.-