• 원자력산업
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• 제36권9호
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• pp.23-28
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• 2016

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제53권10호
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• pp.495-499
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• 2004

Characteristics of ohmic Ni/Si/Ni contacts to n-type 4H-SiC are investigated systematically. The ohmic contacts were formed by annealing Ni/Si/Ni sputtered sequentially The annealings were performed at 950℃ using RTP in vacuum ambient and N₂ ambient, respectively. The specific contact resistivity(p/sub c/), sheet resistance(R/sub s/), contact resistance (R/sub c/) transfer length(L/sub T/) were calculated from resistance(R/sub T/) versus contact spacing(d) measurements obtained from TLM(transmission line method) structure. While the resulting measurement values of sample annealed at vacuum ambient were p/sub c/ = 3.8×10/sup -5/Ω㎠, R/sub c/ = 4.9 Ω and R/sub T/ = 9.8 Ω, those of sample annealed at N₂ ambient were p/sub c/ = 2.29×10/sup -4/Ω㎠, R/sub c/ = 12.9 Ω and R/sub T/ = 25.8 Ω. The physical properties of contacts were examined using XRD 3nd AES. The results showed that nickel silicide was formed on SiC and Ni was migrated into SiC. This result indicates that Ni/Si/Ni ohmic contact would be useful in high performance electronic devices.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.545-546
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• 2006

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• 대한화장품학회지
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• 제36권2호
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• pp.121-128
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• 2010

본 논문에서는 치아 씨앗으로부터 분리한 단백다당체(proteoglycan)의 성분분석과 분자량 측정 및 피부보습 효과를 연구하였다. 분리된 단백다당체의 성분분석 결과 치아 씨앗 단백다당체를 이루고 있는 당 성분(%)은 galactose (46.8), glucuronic acid (27.1), rhamnose (8.7), xylose (7.6), glucose (4.9), fructose (2.3), mannose (1.8), arabinose (0.9)로 확인되었으며, 함유된 단백질의 함량은 31.3 mg/g으로 이를 구성하는 아미노산 성분(mg/g)은 Asp (1.9), Glu (3.6), Ser (0.9), Gly (3.6), Thr (0.8), Arg (1.0), Ala (2.0), Tyr (0.4), Cys (4.8), Val (1.1), Phe (0.5), Ile (0.6), Leu (0.9)로 확인 되었다. Gel permeation chromatography (GPC)에 의해 측정한 치아 씨앗 단백다당체의 분자량 범위는 100,000~250,000 Da로 분자량 분포에 의한 평균 분자량은 170,000 Da이었다. 또한, 사람을 이용한 피부수분 보유 효과 및 피부 수분 손실량을 평가한 결과, 피부의 수분함량을 유지하는 효과가 우수하였으며 표피 수분 손실량 또한 적어서 피부 보습제로서 매우 우수하였다. 결론적으로 치아 씨앗의 다당체로부터 분리한 단백다당체를 화장품에 응용하면 우수한 보습효과를 가지는 화장품을 개발 할 수 있을 것으로 사료된다.

• 설비공학논문집
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• 제16권5호
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• pp.444-451
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• 2004

Flow condensation heat transfer coefficients (HTCs) of R22, R134a, R407C, and R410A were measured on horizontal plain and microfin tubes. The experimental apparatus was composed of three main parts; a refrigerant loop, a water loop and a water/glycol loop. The test section in the refrigerant loop was made of both a plain and a microfin copper tube of 6.0∼6.16 mm inside diameter and 1.0 m length. Refrigerants were cooled by passing cold water through an annulus surrounding the test section. Tests were performed at a fixed refrigerant saturation temperature of 4$0^{\circ}C$ with mass fluxes of 100, 200, and 300 kg/m2s. Test results showed that at similar mass flux the flow condensation HTCs of R134a were similar to those of R22 for both plain and microfin tubes. On the other hand, HTCs of R407C were lower than those of R22 by 4∼16% and 16∼42% for plain and microfin tubes respectively. And HTCs of R410A were similar to those of R22 for a plain tube but lower than those of R22 by 3∼9% for a microfin tube. Heat transfer enhancement factors of a microfin tube were 1.3∼1.9.

• 설비공학논문집
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• 제20권2호
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• pp.87-96
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• 2008

Flow condensation heat transfer coefficients(HTCs) of R123 and R245fa are measured in a horizontal plain tube. The main test section in the experimental flow loop is made of a plain copper tube of 9.52 mm outside diameter and 530 mm length. The refrigerant is cooled by passing cold water through an annulus surrounding the test section. Tests are performed at a fixed saturation temperature of $50\;{\pm}\;0.2\;^{\circ}C$ with mass fluxes of 50, 100, $150\;kg/m^2s$ and heat flux of $7.3{\sim}7.7\;kW/m^2$. Heat transfer data are obtained in the vapor quality range of $10{\sim}90%$. Test results show that the flow condensation HTCs of R245fa are overall 7.9% higher than those of R123 at all mass fluxes. The pressure drop of R245fa is smaller than that of R123 at the same heat flux. In conclusion, R245fa is a good candidate to replace ozone depleting R123 currently used in chillers from the view point heat transfer and environmental properties.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1429-1435
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• 2002

The absolute stereochemistry of tetrin B (1), an antifungal antibiotic isolated from a soil actinomycete was determined by applying Rychnovsky analysis, the modified Mosher method, and CD exciton chirality to be 4R, 5R, 7S, 9R, 11S, 12R, 13S, 15R, 24S, and 25R.

• Bulletin of the Korean Chemical Society
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• 제19권1호
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• pp.115-118
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• 1998

• Journal of Acupuncture Research
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• 제24권1호
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• pp.111-125
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• 2007

Objection : The aim of this study was to investigate anti-ischemic effect of LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture. Methods : I designed to investigate whether LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture affects cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), mean arterial blood pressure (MABP) ] in normal and cerebral ischemia rats by MCA occlusion method, and to make manifest whether LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. The changes of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was determinated by video microscope and width analyzer. Results: The results were as follows ; 1. LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture was significantly increased rCBF, PAD, but decreased MABP after withdrawing of the needle. This results suggest that LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced significantly rCBF by dilating PAD. 2. Pretreatment with indomethacin (1mg/kg, i.v.) was significantly inhibited LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced increase of rCBF and PAD, but increased LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced decrease of MABP after withdrawing of the needle. 3. Pretreatment with methylene blue(10/${\mu}$g/kg, i.v.) was decreased LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced increase of rCBF and MABP, but accelerated LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture induced decrease of PAD. This results suggest that the mechanism of LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. Conclusion : I suggest that LR1 ${\cdot}$ HT8 ${\cdot}$ HT9 Reinforcement in Acupuncture has an anti-ischemic effect through the improvement of cerebral hemodynamics, and the mechanism IS mediated by cyclooxygenase.

• 한국동물학회지
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• 제18권4호
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• pp.163-172
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• 1975

생쥐에 400 및 800 R의 X線을 一時全身照射한 뒤, 몇가지 臟器에서 Dische 陽性物質의 放出量과 CdR-aminohydrolase의 活性變化 및 尿중의 CdR量을 照射후의 時間經過에 따라 측정하여 放射線照射후 deoxycytidineuria의 增加機構의 一面을 究明하려고 시도했다. CdR-aminohydrolase의 活性度는 照射후 1時間째에 小腸과 肝에서 顯著한 감소를 보였으며, 5$\\sim$12시간 사이에 정상水準으로 복귀되었다가 3日째에 最大의 증가를 나타냈다. 한편, 脾臟과 血液의 경우는 對照群과 照射群에서 모두 극미한 活性만이 관찰되었다. Dische 陽性物質의 放出量은 小腸의 경우 照射후 3$\\sim$12시간 사이에 증가를 보였으며 6$\\sim$9시간에 最大値를 나타냈다. 이에 반해서 肝, 脾臟 및 賢臟의 경우는 小腸에 비해 1/20 이하에 불과하였으며, 이들 조직은 照射후 증가하는 deoxycytidineuria에 직접 寄與하지는 않는 것으로 생각된다. Deoxycytidineuria는 照射후 9$\\sim$12시간에 最大値를 보였는데, 이의 相當量이 小腸에 연유하는 것으로 믿어지고, 특히 小腸의 CdR-aminohydrolase의 活性度의 변화와 깊은 關連이 있는 것으로 생각된다. 즉 放射線照射후 DNA分解産物중 CdR이 CdR-aminohydrolase의 活性이 격감하는 시기에 조직으로부터 血液으로 放出되고, 血液내에서는 별다른 量的변화를 거치지 않고 尿에 섞여 排泄되는 것으로 思料된다.