• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.223-228
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• 1997

밀도가 온도의 변화에 따라 비선형적으로 변하는 경우, 예를 들어 공업적으로 많이 이용되고 있는 저온의 물인 경우에는 $4^{\circ}C$부근의 최대밀도점의 존재로 인해 매우 특이한 유동형태 및 열전달 특성이 나타난다. 또한 유체와 접하는 고체면이 평판의 경우와는 달리 어떤 일정의 곡률을 가지는 원기둥일 경우에는 곡률반경의 효과에 대한 특성이 고려되어야 한다. 이러한 현상은 공업적 측면뿐만 아니라 자연환경의 변화 등에서 매우 중요한 의미를 갖는다. (중략)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1992.05a
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• pp.25-25
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• 1992

1.형질전환 조건 설정: 페염균을 casein hydrolysate배지에서 배양하여 550nm에서의 흡광도가 0.1이 되었을 때 pH를 7.0으로 낮추고 형질전환 능력이 나타나도록 할 때에는 pH를 7.6으로 높여 줌으로써 형질전환이 원하는 시기에 발현되도록 함. 2.돌연변이원에 대한 감수성 측정: com- mutant는 야생형보다 돌연변이가 일어난 위치에 따라 UV에 대한 감수성의 차이가 나타났으나 EMS에 대해서는 야생형과 큰 차이가 얼었음. 3.온도민감성: 5시간동안 43$^{\circ}C$에서는 37$^{\circ}C$에서의 생장율의 5%만 증가되었으나 5$0^{\circ}C$에서는 전혀 성장하지 않음.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.254-257
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• 2004

닭 도계가 완료된 도체에 $52^{\circ}C$, 1% lactic acid를 이용하여 분무세척하면 육질에 영향을 미치지 않으면서 총호기성균 뿐만 아니라 대장균, E. coli 및 L. monocytogenes의 감소에 효과적일 것으로 사료된다. 하지만 S. typhimurium를 효과적으로 감소시키기 위해서는 온도를 높이거나 처리시간을 연장시키는 것이 좋을 것으로 판단된다.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1994.11a
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• pp.84-89
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• 1994

주유동에 수직으로 분사된 제트 화염의 구조는 이해하기 위하여 화염 길이와 온도를 측정하고 reactive mie scattering 방법을 이용하여 단면 가시화를 실시하였다. 주유동 속도와 제트 분사 속도의 증가에 따라 화염 길이도 함께 증가함을 알 수 있고, 단면 가시화 결과 화염 내부에 존재하는 inner vortical structure는 일반적인 동축제트 화염과 같은 대칭 구조를 갖지 앉고 유동 조건에 따라 inner vortical motion 의 생성 위치가 변화함을 알 수 있다 이는 본 유동장의 특성 중의 하나인 bound vortex와 제트와 주유동이 접하는 상류 면에서 발생하는 rolling-up 의 강도에 좌우됨을 알 수 있다.

• Applied Biological Chemistry
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• v.11
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• pp.83-88
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• 1969

94 Cellulase producing strains were isoated from soils, composts, rotten woods and straws, and gastric contents and feces of herbivorous animals in various places. Among them, the strain MC-9, MC-10, MC-53 and MC-61 were found to be highly active in the degradation of carboxy methyl cellulose. Their cultural conditions adequate for the cellulase formation and effects of inorganic salts and various organic substances added to the wheat bran media were investigated. The results obtained are as follows; 1. Optimum conditions for the cellulase formation were MC-9: pH 5.5, temp. $35^{\circ}C$, incubation time 5 days, MC-10: pH 5.5-6.0, temp. $30^{\circ}C$, incubation time 5 days, MC-53: pH 3.5, temp. $30^{\circ}C$, incubation time 5 days, MC-61: pH 3.5-4.0, temp. 30-$35^{\circ}C$, incubation time 5 days. 2. Their cellulase activity in their optimum conditions were MC-9: CMC-LP(liquefying power). 87.7%, CMC-SP(saccharifying power) 3.20 glucose mg./gm. of the cultures/min., MC-10: CMC-LP 82.9%, CMC-SP 2.48 glucose mg./gm. of the cultures/min., MC-53: CMC-LP 72.4%, CMC-SP 1.76 glucose mg./gm. of the cultures/min., MC-61: CMC-LP 87.1%, CMC-SP 2.08 glucose mg./gm. of the cultures/min. 3. Additions of inorganic salts to the wheat bran media were not significant for the cellulase formation, but additions of soybean film and orange-peel pomace promoted the CMC-liquefying power 3 to 5 percent in wheat bran cultures of the strains.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.4 no.2
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• pp.169-177
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• 1994

Dilute Al-Cu and Al-Mg alloys were solidified unidirectionally upward by Bridgman method. It is necessary that solute concentration of initial melt is uniform to be able to control the concentration of crystal. When solute concentration is not uniform, it can cause unusual macro-segregation in grown solid. A non-steady state solidification was observed where the solute concentration in the grown solid decreased with the progress of solidification, when a dilute Al-Cu melt with positive axial temeprature gradient was solidified. This was caused by leaking out of Cu-rich melt into the gap between ingot and crucible during melt-down and its sedimentation after complete melting. In the case of Al-Mg alloy, the solute concentration has a minimum in the middle of grown specimen because Mg-rich melt flowed down the gap between ingot and crucible and floated after complete melting. Uniform initial melt concentration can be achieved by the homogenization of the ingot or by the absence of the gap between ingot and crucible.

• Korean Journal of Ecology and Environment
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• v.53 no.1
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• pp.73-79
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• 2020

Metarhizium anisopliae is one of the entomopathogenic fungi infecting Protaetia brevitarsis seulensis. Environmental conditions strongly affect the virulence of entomopathogenic fungus. To test the susceptibility of P. brevitarsis seulensis larvae to M. anisopliae, we determined level mortality rates under different rearing conditions: temperatures (20℃, 25℃, 30℃), relative humidities (RH; RH 40%, 50%, 60%, 70%), and water content in sawdust (40%, 50%, 60%). The mortality rate of larvae treated with 5×10⁶ conidia mL^-1 M. anisopliae was not significantly affected by rearing temperature, but was affected by low RH (40%) and low water content in sawdust (40%), both of which resulted in high mortality rates. Mortality rated among M. anisopliae-treated 1^st, 2^nd, and 3^rd instar larvae were highest in 1^st instar larvae.

• Journal of Life Science
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• v.14 no.1
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• pp.174-179
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• 2004

To develop high effiency biofertilizer, a bacterium having ability to solubilize inorganic phosphate was isolated from cultivated soils, using a sucrose minimal agar-hydroxyapatite medium. The strain was identified as Klebsiella sp. DA7l-1, based on the physiological and biochemical properties. The activity of solubilizing inorganic phosphate of Klebsiella sp. DA7l-1 against three types of insoluble phosphate such as tri-calcium phosphate, aluminium phosphate, hydroxyapatite were quantitatively determined. The results indicated that the strain solubilized hydroxyapatite. The MPS (mineral phosphate solubilizing) conditions of Klebsiella sp. DA7l-1, were measured to determine the optimal conditions. The optimal temperature and initial pH to solubilize insoluble phosphate in sucrose minimal medium were $30^{\circ}C$ and pH 6.0, respectively.

• Research in Plant Disease
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• v.9 no.1
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• pp.47-51
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• 2003

Sclerotinia rot of C. japonica caused by Sclerotinia sclerotiorum was observed throught the growing season in the vinylhouse at the Namyangiu, Yangju and Yangpyung areas. The disease was commonly occurred at late autumn after transplanting and continuously increased until spring in next year, The disease was especially severe at the Yangpyung area among three areas. Three isolates of S. sclerotiorum obtained from C. japonica in different geographic areas were evaluated for ability of sclerotia formation and viability under different temperature. Temperature for mycelial growth ranged from 5 to 3$0^{\circ}C$, with optimum temperature at 15~3$0^{\circ}C$. Sclerotia were fewer formed at low temperature, but their size was larger than that at high temperature. Small size of sclerotia was more viable than those of large size at high temperature. Based on the differences in viability of sclerotia, the relative ranks of sclerotia were in order ~2 mm > 3~4 mm > 5 mm~.

• Applied Chemistry for Engineering
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• v.35 no.5
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• pp.429-437
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• 2024

Dry reforming of methane (DRM) uses natural gas and carbon dioxide as reactants to produce hydrogen, potentially providing a solution for reducing greenhouse gas emissions and offering an alternative carbon-free energy source. However, since DRM is highly endothermic, its application and commercialization are limited by rapid temperature decrease and resulting catalyst inactivation. Consequently, research into catalyst development and reactor design to mitigate temperature decline is essential. In this study, computational fluid dynamics (CFD) is utilized to develop a multiphysics simulation platform for DRM within a fixed-bed reactor, employing two types of spherical catalysts: eggshell and uniform types. Our findings indicate that the eggshell model can maintain a higher temperature at the reactor's core than the uniform catalyst model by approximately 20 K. Furthermore, the eggshell model demonstrates superior methane conversion and hydrogen yield due to its ability to suppress excessively rapid reactions. These results underscore the benefits of eggshell catalysts in highly endothermic reactors, such as those used in DRM processes. The developed simulation platform can be used to assess various combinations of reactor and catalyst designs and further optimize their dimensions and operational protocols.