• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.113-114
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• 2000

The secondary electron emission coefficient(${\gamma}$) of vacuum annealed MgO films has been investigated by ${\gamma}-focused$ ion beam(${\gamma}-FIB$) system. The vacuum annealed MgO films have been found to have higher ${\gamma}$ values from 0.053 up to 0.121 than those for as-deposited MgO films from 0.026 up to 0.062 for $Ne^+$ ion energies ranged from 50eV to 200eV. Also it is found that ${\gamma}$ for air hold of vacuum annealed MgO layers for 24-hours is similar to that for vacuum annealed MgO films without any air-hold.

• Journal of Pharmaceutical Investigation
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• 제7권1_4호
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• pp.38-50
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• 1977

A study on the mechanism of biliary and urinary excretion of chloramphenicol has been performed in the dog. 1) Chloramphenicol administered intravenously to dogs with ligated renal pedicle, readily appeared in bile greater than in plasma. 6.9% of a 50mg /kg i. v. dose of chloramphenicol were excreted into bile within 100 minutes. During the same periods of above experiment, the bile/plasma concentration ratios(B/P ratios) were 46 to 87. 2) Chloramphenicol injected into the vein of dog was rapidly excreted into urine. 18% of the administered dose were excreted into urine within 70 minutes. In the same periods of this experiment, Ccm/Ccr ratios were greater than 1.0 in most cases. 3) In experiment of simultaneous measurement of biliary and urinary excretion of chloramphenicol, Ccm/Ccr ratios were less than 1.0 and B/P ratios were 50 to 52. 4) In experiment measured simultaneously biliary and urinary excretion both Ccm/Ccr and $C^Hcm$(hepatic clearance) were significantly declined by probenecid, but not affected by 2,4-DNP and aminophylline although 2,4-DNP increased only bile flow and aminophylline both bile and urine volume. 5) Ccm/Ccr and $C^Hcm$ were increased in proportion to increment of plasma concentration ranging from 3.3 to 30 mg% of chloramphenicol. But when plasma concentration were increased to 70mg %, Ccm/Ccr were not increased and $C_Hcm$ were reduced about 30% in comparison with values obtajned at 30mg% of chloramphenicol. 6) Free/Bound(free to bouid from) ratios ranging from 1.0 to 90.0mg% of chloramphenicol were 76.2+3.72% $(mean{\pm}S.E.)$ Above results suggest that chloramphenicol is excreted into bile by a process of active trasport, that excretion of chloramphenicol into urine was made up with dual process, reabsorption and secretion, and that renal secretion was attained by active trasport process although renal reabsorption process could not understand.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 추계학술발표논문집
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• pp.180-186
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• 1999

Alkaline peroxide bleaching of (chemi) mechanical pulp is a very complicated system where various process factors affect the bleaching performance and pulp properties. Traditional on-factor-at a time method is ineffective and costly in finding the optimal bleaching conditions. In this study statistical experimental methods which include three steps. I. e. screening, response surface modeling and optimization, were used to find the conditions for maximal brightness development during one stage alkaline peroxide bleaching of TMP which had an initial brightness of 54.5% Elerpho. The TMP was pretreated with EDTA(0.5% on O. D. pulp. consistency, $30^{\circ}C$ for 60 minutes) and bleached in a 2L Mark V Quantum Reactor at 750rpm, 7.5% of bleaching consistency and with 0.05% magnesium sulfate addition. The ranges of other factors studied were 1~5% hydrogen peroxide on O. D plup, 1~4% sodium hydroxide on O. D pulp and 1~4% sodium silicate on O. D pulp, reaction temperature 50~$90^{\circ}C$ and reaction time 40~180minutes. A models with good predictability was established and the maximal brightness after one stage bleaching was found to be 70% Elerpho at $50^{\circ}C$, 50 minutes 5% hydrogen peroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D pulp and 4% silicate on O. D pulp. However further studies on other pulp properties such as strength and brightness stability shall be carried out in order to find out the optimal bleaching conditions.

• Food Science and Biotechnology
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• 제16권6호
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• pp.963-966
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• 2007

The objectives of this study were to identity antioxidant substance in heated garlic juice (HGJ). We evaluated the antioxidant activities of heated garlic juice exposed to 120, 130, and $140^{\circ}C$ for 2 hr. The HGJ was partitioned using the solvents of hexane, chloroform, ethyl acetate, butanol, and water. The ethyl acetate fraction of HGJ treated at $130^{\circ}C$ for 2 hr showed strong antioxidant activity; this extract was isolated and purified using silica gel column chromatography and semi-preparative high-performance liquid chromatography. The structure of the purified compound was determined using spectroscopic methods, i.e., ultraviolet, mass spectrometry, infrared, $^1H$ NMR, $^{13}C$ NMR, DEPT, HMBC, and HMQC. The isolated compound was identified as thiacremonone (2,4-dihydroxy-2,5-dimethyl-thiophene-3-one). Thiacremonone showed strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, with a 50% inhibition concentration ($IC_{50}$) of $22.25{\pm}0.44\;{\mu}g/mL$, which is much higher than that of the antioxidants ascorbic acid ($30.06{\pm}0.42\;{\mu}g/mL$), ${\alpha}$-tocopherol ($71.30{\pm}0.97\;{\mu}g/mL$), and butylated hydroxyanisole ($50.54{\pm}0.94\;{\mu}g/mL$).

• Structural Engineering and Mechanics
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• 제49권2호
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• pp.261-271
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• 2014

This paper reported an experimental study on creep behaviors of PVB and Ionoplast laminated glass (LG) under load duration of 30 days. The tests were carried out in room temperature ($23^{\circ}C$). The study revealed that after sustaining loads for 30 days, the mid-span deflection of PVB LG increased by almost 102% compared with its short term deflection, while that of Ionoplast LG approximately increased by 14%; composite effects between two glass plies in PVB LG gradually reduced with time, but did not fully vanish at the 30th day; two glass plies in Ionoplast LG on the other hand was able to withstand loads as an effective composite section during the entire loading period; the creep behaviors of both LG were not finished yet at the 30th day. In addition to this, also studied was the varying of the bending stresses of PVB and Ionoplast LG under load duration of 2 hours. The tests were carried out in ambient temperatures of $30^{\circ}C$, $50^{\circ}C$ and $80^{\circ}C$ respectively. It was found that under a given load, although the bending stresses of both LG increased with increasing temperature, for PVB LG the increasing rate of the bending stress decreased with increasing temperature, while for Ionoplast LG the increasing rate of the bending stress increased with increasing temperature.

• 한국진공학회지
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• 제5권3호
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• pp.245-250
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• 1996

$Y_2O_3$ thin film on si(100) was successfully grown by ionized cluster beam(ICBD) technique at substrate temperature of around $500^{\circ}C$ and pressure of ~$10^{-5}$Torr.To prevent the oxidation of Si substrae, a very thin yttrium layer was deposited on Si before reactive depositing of oxygen and yttrium source. In asdeposited stage, b.c.c and h.c.p strucutres of $Y_2O_3$ were observed from S-ary analysis. From the observation of spots and ring patterns in selected area diffractin(SAD) patterns. crystallane formation and growth could be proceeded during the deposition. $Y_2O_3$/mixed layer/$SiO_2=170\AA/50\AA/10\AA$ structure were verified by high resolution transmition electron imcroscopy(HRTEM) image, and the formation of amorphous layer of SiO2 was discussed . Electricla charateristics of the film were also investigated . In as-deposited Pt/$Y_2O_3$/Si sturcuture, leakage current was less than $10^{-6}$A/$\textrm{cm}^2$ at 7MV/cm strength.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2002년도 추계기술심포지움논문집
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• pp.109-113
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• 2002

본 연구에서는 공침법에 의한 초미세분말을 이용하여 제조된 (NiCuZn)-ferrite와 건식법을 이용하여 제조된 (NiCuZn)-ferrite의 저온소결 특성 및 전자기적 특성을 상호 비교 분석하였다. 조성은 (N $i_{0.4-x}$C $u_{x}$Z $n_{0.6}$)$_{1+w}$(F $e_2$ $O_4$/)$_{1-w}$에서 x의 값을 0.2, w의 값은 0.03으로 고정하였고, 소결은 공침법으로 합성된 분말의 경우 초기열처리과정을 거쳐 최종적으로 90$0^{\circ}C$에서, 건식법의 경우 11$50^{\circ}C$의 온도에서 진행하였다. 그 결과, 공침법으로 제조된 (NiCuZn)-ferrite는 건식법으로 제조된 (NiCuZn)-ferrite보다 20$0^{\circ}C$이상 낮은 소결온도에서 높은 소결밀도 값을 가졌으며, 품질계수 등 칩 인덕터에서 중요한 요소인 전자기적 특성이 우수하게 나타났다. 또한, 공침법으로 합성된 페라이트는 분말의 초기열처리온도에 따라 최종소결 특성이 크게 변하였다. 그밖에 공침법과 건식법으로 합성한 (NiCuZn)-ferrite의 결정성, 미세구조들을 XRD, SEM, TEM을 이용하여 비교 고찰하였다.하였다.다.

• International Journal of Industrial Entomology and Biomaterials
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• 제3권2호
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• pp.113-116
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• 2001

Fifth instar larvae of the new bivoltine hybrid (CSR2 ${\times}$ CSR5) were reared under different temperature and humidity viz., $20^{\circ}C$ and 85 ${pm}$ 5% R.H (T1), $25^{\circ}C$ and 70 ${pm}$ 5% R.H (T2-Optimum), $30^{\circ}C$ and 80% ${pm}$ 5 R.H (T3) and $35^{\circ}C$and 50 ${pm}$ 5% R.H (T4). The cocoon yield, cocoon characters and disease incidence were studied in normal (non infectious source, i.e control) rearing as well as in 1% infectious source of rearing. The results indicated that V instar larval duration was prolonged and cocoon weight was improved in T1. ERR and shell ratio were significantly improved and disease incidence was minimised in T2. Further significant difference was observed among the treatments with regard to spread of diseases.

• 한국응용곤충학회지
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• 제14권3호
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• pp.111-131
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• 1975

한국에 있어서 벼 흰빛잎마름병의 방제 대책을 강구하기 위하여 피해, 병원균의 성질, 발병환경, 품종의 저항성, Bacteriophage에 의한 발생예찰 및 약제방제에 관하여 1965년부터 1975년까지 얻은 시험 결과를 요약하면 다음과 같다. 1. 피해 우리나라에 있어서 흰빛잎마름병은 거이 전국적으로 분포하여 피해를 주고 있으며 매년 발생이 증가하는 경향이다. 본병발생면적과 이병성품종인 진흥 및 전남풍의 재배면적 증가 사이에는 $5\%$ 수준의 유의성이 있었다. 지역별 피해상황은 남해안지대인 전남, 경남을 비롯하여 서해안지대에서 심하며 또 지대 별로 보면 저위 침수지역이 심하다. 피해 해석 결과 출수기의 병반 면적율과 수량과는 고도의 부(일)의 상관이 있었으며 병반면적율이 $20\%$ 이하에서는 수량에 미치는 영향이 적었으나 $60\%$이상되면 약 $50\%$ 내외의 감수를 초래하였다. 2. 병원균 공시한 10균주 모두 glucose, galactose를 분해하였고 lactose, dextrin, starch는 분해하지 못하였으며 saccharose, raffinose, manitol, manitol, esculin, salicin등의 탄소원에 대하여는 균주 간에 다소 차이가 있었다. 또 균주에 따라 gelatin 액화 정도에 차이가 있었다. 전국 72개 지역에서 채집 분리한 106균주를 4가지 Bacteriophage의 용균 반응에 따라 분류한 결과 1965년의 2계통에서 1971년에서 9계통으로 점차 다양화되었다. 또 진흥에서는 주로 A, B, C, I등이 분리되었고 김남풍에서는 A, B, H, I가 분리되었으며 통일에서는 D, E를 제외한 거의 모든 계통이 분리된 반면 E계통은 아끼바레에서만 분리되었다. 3. 발생환경 7-8월 중에 평년보다 기온이 낫고 습도가 높으며 강우량이 많고 일조시수가 적을 때 발병이 많았다. 출수기를 전후하여 태풍과 침수는 본병을 유발 및 만연시키는 가장 큰 원인이 되었고 이앙기가 빠를수록 발병이 많았다. 4. 저항성 검정 흰빛잎마름병에 대한 저항성 검정방법 가운데서 가위 접종법이 발병 진전이 빠르고 가장 효율적이었다. 우리나라 주요 장려 품종 중에서는 저항성 품종은 없었고 백금, 농림 6호가 중도 저항성이었다. 5. 발생예찰 전년에 발병했던 논에 설치한 못자리에서 병원균이 검출되었고, 관계수중의 Bacteriophage의 발생량과 병발생과는 높은 상관이 있었다. 관계수 1cc당 50개 내외의 Phage가 검출되면 초발을 예견할 수 있었고 Phage의 발생소장 곡선과 15일후의 발병 곡선이 거의 일치됨에 따라 관개수중의 Phage. 발생소장을 조사함으로서 2주일 앞서 발생예찰이 가능하였다. 6. 약제방제 발병 초기부터 1주간격으로 3회 약제 살포하였을 때 훼나진, 상케루 수화제 살포구는 발병율이 떨어졌으며 수량도 $20\%$ 정도 증수되었다. Bacteriophage 발생소장을 이용해서 약제방제할 때에는 Phage가 50개 내외 정도 나타날 때 살포하는 것이 가장 효과적이다.

• BMB Reports
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• 제37권4호
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• pp.454-459
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• 2004

Experimental hyperoxia represents a suitable in vitro model to study some pathogenic mechanisms related to oxidative stress. Moreover, it allows the investigation of the molecular pathophysiology underlying oxygen therapy and toxicity. In this study, a modified experimental set up was adopted to accomplish a model of moderate hyperoxia (50% $O_2$, 96 h culture) to induce oxidative stress in the human leukemia cell line, U-937. Spectrophotometric measurements of mitochondrial respiratory enzyme activities, NMR spectroscopy of culture media, determination of antioxidant enzyme activities, and cell proliferation and differentiation assays were performed. The data showed that moderate hyperoxia in this myeloid cell line causes: i) intriguing alterations in the mitochondrial activities at the levels of succinate dehydrogenase and succinate-cytochrome c reductase; ii) induction of metabolic compensatory adaptations, with significant shift to glycolysis; iii) induction of different antioxidant enzyme activities; iv) significant cell growth inhibition and v) no significant apoptosis. This work will permit better characterization the mitochondrial damage induced by hyperoxia. In particular, the data showed a large increase in the succinate cytochrome c reductase activity, which could be a fundamental pathogenic mechanism at the basis of oxygen toxicity.