• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.400-401
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• 2001

본 연구는 주변에서 흔히 구할 수 있는 여뀌를 이용하며 유용한 미생물을 대량생산 할 수 있는 값싼 배지를 개발하는데 있다. 길항미생물 B. lentimorbus G-74를 이 배지를 이용하여 최적화한 결과, 30% 여뀌즙액 배지. $35^{\circ}C$. pH 5.0의 조건에서 가장 높은 균체성장을 보였다.

• 한국세라믹학회지
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• 제27권1호
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• pp.27-34
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• 1990

Single crystals of YBa2Cu3Ox superconductor were grown by means of the flux method. The effectof starting material, cooling rate, melting time, and melting temperjature were evaluated as influencing paraemters. The larger single crystals of YBa2Cu3Ox were obtained with Y2BaCuOy powder as a starting material than with YBa2Cu3Ox powder. The optimum range of synthetic condition for single crystal growth was as follows ; 2-5$^{\circ}C$/hour of cooling rate, 2-5 hour of melting time and melting temperature at 106$0^{\circ}C$. The obtained size of single crystal was 2mm in average and the largest one was 5mm in maximum.

• Corrosion Science and Technology
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• 제9권3호
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• pp.137-141
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• 2010

Sodium nitrite is widely used as one of the popular corrosion inhibitors for the protection of ferrous metal in closed cooling water system, such as a diesel engine and a chiller. The optimum treatment conditions are studied through laboratory tests using linear polarization resistance (LPR) technique. Corrosion rate of the carbon steel electrode could be maintained less than $2.5{\times}10^{-3}$ mmpy in the test condition of 500 ppm as ${NO_2}^-$, 200 ppm as $Cl^-$, $70^{\circ}C$ and pH 6.8. The pH control is confirmed not to be an important factor in the protection of carbon steel by sodium nitrite inhibitor. The addition of tolyltriazole was needed for the protection of the copper alloy in the sodium nitrite treatment system.

• 한국미생물·생명공학회지
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• 제25권5호
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• pp.435-441
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• 1997

Forty seven strains of yeast were isolated from traditional Meju and were identified as Saccharomyces spp. (7 strains), Zygosaccharomyces spp. (7 strains), Kluyveromyces spp. and Hansenula spp. (each 5 strains), Rhodotorular spp. (8 strains), Candida spp. (12 strains), Pichia spp. and Debaryomyces spp. from results of their microbiological characteristics. The optimal medium for growth of all the yeasts was YM media and the optimal initial pH of the medium was 6.0. The optimum temperature for growth was 30$circ$ and among them, Sacch. exiguus OE-5, Sacch. cerevisiae OE-16, Sacch. kluyveri C-1 strains were thermotolerant yeasts which could grow at 40$circ$C.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.935-938
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• 2001

Carbon nanotubes(CNTs) was successfully grown on Ni coated silicon wafer substrate by applying PECVD technique(Plasma Enhanced Chemical Vapor Deposition). As a catalyst, Ni thin film of thickness ranging from 15∼30nm was prepared by electron beam evaporator method. In order to find the optimum growth condition, the type of the gas mixture such as C$_2$H$_2$-NH$_3$was systematically investigated by adjusting the gas mixing ratio in temperature of 600$^{\circ}C$ under the pressure of 0.4 torr. The diameter of the grown CNTs was 40∼150nm. As NH$_3$etching time increased the diameters of the nanotubes decreased whereas the density of nanotubes increased. TEM images clearly demonstrated synthesized nanotubes was multiwalled. We investigated electrical properties for the application of FED.

• 대한전기학회논문지
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• 제41권1호
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• pp.56-62
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• 1992

The GaAs bulk crystals are grown by the Synthesis Solute Diffusion(SSD) method and its properties are investigated. The crystal growth rate at optimum condition is 0.28 cm/day and their temperature dependence is R(T) = 2.92 x 10S04T exp(-1.548eV/kS1BTT) [cmS02T/day.K]. Etch pits density distribution along radial direction is order of 10S04TcmS0-2T and 10S03TcmS0-2T at the edge and middle of the wafers, respectively, and it increased exponentially along vertical direction of ingot. Moreover,it is uniformly distributed as order of 10S03TcmS0-2T in radial direction of In doped GaAs. The carrier concentration and mobilities are measured to 0.34-2.1 x 10S016T cmS0-3T and 2.3-3.3x10S03T cmS02T/V.sec, respectively.

• 한국결정성장학회지
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• 제6권4호
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• pp.480-492
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• 1996

Al이 2 wt% 포함되어 있는 Zn 금속 target을 사용하여 반응성 직류 magnetron sputtering법으로 AZO(Aluminum doped Zinc Oxide) 투명전도막을 제막하였다. 반응성 가스인 산소의 분압과 유량을 조절하여 투과율과 전도도가 모두 우수한 전이영역을 발견하였고 전이영역을 안정적으로 유지하기 위한 증착조건을 찾아냈다. ZnO:Al막의 XRD분석결과 산화막이나 전이영역에서 증착된 막들은 ZnO결정의 (002)면의 peak가 유일하게 관찰되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.328-331
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• 2000

Carbon nanotube(CNT) was successfully grown on Ni-W alloyed substrate by applying PECVD technique(Plasma Enhanced Chemical Vapor Deposition). As a catalyst, Ni-W alloyed substrate was prepared by mechanical alloying method. In order to find the optimum growth condition, initially two different types of gas mixtures such ac $C_2$H$_2$-H$_2$and $C_2$H$_2$-MH$_3$were systematically investigated by adjusting results on the mixing ratio in temperature range of 500 to 80$0^{\circ}C$. In this work, we will report the preliminary results on the CNT processed by PECVD, which were characterized by XRD, SEM and TEM. Finally we will evalute the effect on CNT growth by changing many processing parameters, such as typical gas, mixing ratio between 2 mixture, plasma power and etc.

• 한국재료학회지
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• 제17권1호
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• pp.56-59
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• 2007

Recently, requirement for the ultra thin copper foil increases with smaller and miniaturized electronic components. In this study, we evaluated the surface morphology, crystal phase ana surface roughness of the copper film electrodeposited by pulse method without using additives. Homogeneous and dense copper crystals were formed on the titanium substrate, and the optimum condition was 25% duty cycle. Moreover, the surface roughness(Ra), $0.295{\mu}m$, is the smallest value in this condition. It is thought that this copper foil is good for electromigration inhibition due to the preferential crystal growth of Cu (111)

• 한국자원식물학회지
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• 제32권3호
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• pp.237-243
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• 2019

Soybean is the one of recalcitrant legume species for shoot induction. Shoot regeneration via direct organogenesis was investigated in five soybean cultivars, 'Dawon', 'Pungsan', 'Daewon', 'Taekwang' and 'Chongdoo 1' by using cotyledonary node explants. Out of 5 soybean cultivars, an efficient shoot regeneration condition was developed in the two soybean cultivars, 'Dawon' and 'Pungsan'. When various kinds of plant growth regulators with different concentration were estimated, the optimum medium condition for shoot induction in both soybean cultivars was MS + B5 vitamin supplemented with BA at concentration 2 mg/L. In addition, shoot formation efficiency was increased with 97.09% and 93.88% by the pretreatment of BA onto the explants before in vitro culture in both cultivars. Shoot induction in 'Dawon' cultivar was originated from epidermal tissue and sub-epidermal layers when histological changes were investigated under shoot regeneration after culturing cotyledonary node segments on shoot induction medium for 0 to 21 days. Especially, cell dedifferentiation was observed from parenchyma cells to meristematic cell in 3-day cultured segments.