• Mycobiology
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• 제30권4호
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• pp.228-232
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• 2002

This study focused on the production of high quality compost for the growth of aero-thermophilic fungi, which has a promoting effect on the growth rate and production of oyster mushrooms. The automated solid-state bioreactor system was designed on the basis of a Three-Phase-One system, which controls the serial steps of prewetting, pasteurization and fermentation processes. High numbers of thermophilic fungi and bacteria were recovered from the mushroom composts prepared by this solid-state bioreactor. The rates of composting process were depended on physical as well as chemical factors. Among these factors, the parameters of moisture content and temperature were found to be particularly important. In our automated system, constant levels of moisture content, temperature and ventilation via mixing were provided by a centralized control apparatus including PLC, water tank and water jacket systems. These features induced higher microbiological activity of aero-thermophiles.

• 대한기계학회논문집
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• 제18권9호
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• pp.2404-2412
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• 1994

A mathematical model has been developed for predicting kinematic, thermal, and solidification histories of atomized droplets during flight. Liquid droplet convective cooling, recalescence, equilibrium-state solidification, and solid-phase cooling were taken into account in the analysis of the solidification process. The spherical shell model was adopted where the heterogeneous nucleation is initiated from the whole surface of a droplet. The growth rate of the solid-liquid interface was determined from the theory of crystal growth kinetics with undercooling caused by the rapid solidification. The solid fraction after recalescence was obtained by using the integral method. The thermal responses of atomized droplets to gas velocity, particle size variation, and degree of undercooling were investigated through the parametric studies. It is possible to evaluate the solid fraction of the droplet according to flight distance and time in terms of a dimensionless parameter derived from the overall energy balance of the system. It is also found that the solid fraction at the end of recalescence is not dependent on the droplet size and nozzle exit velocity but on the degree of subcooling.

• 한국재료학회지
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• 제9권11호
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• pp.1108-1111
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• 1999

결정성장 도중 전류에 의해 고/액 계면에서 발생하는 Peltier 열을 이용하면 온도구배의 증가와 이에 따른 성장속도의 증가 및 결정성의 향상에 기여할 것이라 예상되어, 고/액 계면에서 복합적으로 발생하는 Peltier 효과를 조사하였다. 전류 밀도, 극성 및 온도구배의 변화에 따른 고상과 액상 및 그 계면에서의 온도변화로부터 이론적 추론에 의해 Peltier 열, Thomson 열 및 Joule 열만의 영향으로 분류할 수 있었고, 고상/액상 계에 대한 Peltier 계수 및 Thomson 계수도 구할 수 있었다.

• 한국주조공학회지
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• 제29권5호
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• pp.213-219
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• 2009

Optimum conditions for production of semi-solid Al-Zn-Mg alloy billets was carried out by the Taguchi design method. And, Al-Zn-Mg alloy billets contained Sc (free, 0.1 and 0.3 mass %) were fabricated at optimum conditions. Evolution of microstructure in semi-solid state was investigated through various liquid fractions, holding times and holding temperatures. The Al-Zn-Mg alloy billets reheated at $615^{\circ}C$ during 30min are grain growth and it was fractured due to increasing liquid fraction before quenching. And, during reheating up to $600^{\circ}C$, grain growth of Al-Zn-Mg alloy billets contained Sc (0.1 and 0.3 mass %) was not occurred in comparison with those of Al-Zn-Mg alloy without Sc. It was thought that $Al_3Sc$ phases have a pinning effect in grain boundary and Sc content of 0.1 mass% is able to inhibit grain growth effectively through reheating process.

• 한국진공학회지
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• 제22권2호
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• pp.105-110
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• 2013

Vapor-Liquid-Solid 방법을 이용하여 다양한 성장온도와 V/III 비율 아래 $In_xGa_{1-x}As$ 나노와이어를 실리콘 (111) 기판 위에 성장하였다. 나노와이어 성장은 화학기상증착(MOCVD)장치를 이용하였으며, 나노와이어의 구조적 특성은 주사전자현미경 및 투과전자현미경을 이용하여 분석하였다. 나노와이어의 조성비 분포를 확인하기 위하여 투과전자현미경에 장착된 Energy dispersive X-ray 분석기로 나노와이어의 길이에 따른 In과 Ga의 조성비를 측정하였다. 성장온도와 V/III 비율이 올라갈수록 In 조성비가 나노와이어 내부에서 크게 변하는 것을 확인하였는데, 이는 Vapor-Solid 방식에 의한 나노와이어 표면에서의 성장이 증가하기 때문으로 이해된다.

• 한국결정성장학회지
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• 제2권1호
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• pp.76-85
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• 1992

열전 재료로 사용되는 $Ag_2S$의 단결정을 밀폐된 석영관내에서 고상의 $Ag_2S$가 분해되면서 성장 계면에 $Ag^+$이온과 전자를 공급하고, 휘발성이 강한 황은 vapour 상태로 전송되면서, $Ag_2S$ 계면에서부터 단결정이 성장하는 고상에서의 전기 화학적인 방법을 이용한 vapour 성장법으로 성장시켰다. 고상에서의 $Ag^+$ 이온의 확산이 성장을 지배하는 온도 영역에서는 bulk $Ag_2S$ 단결정을 얻었으며, Ag 분해 온도가 높을수록, Ag분해 온도와 성장 계면의 온도 차이가 클수록 성장속도가 빠름을 확인하였다. 한편 기상으로의 황의 확산이 성장을 지배하는 영역에서는 whisker Ag$_2$S가 성장되었으며 황의 포화 압력이 증가할수록 성장속도는 증가하였다. 또한, 열전재료의 효율을 결정하는 물성치인 전기 전도도를 측정한 결과 고온상에서 다결정의 전기 전도도가 단결정보다 크게 나타나며, 따라서 열전 효율은 다결정이 우수하다고 생각된다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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• pp.116-116
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• 2003

Most of all nano-structures, SiC had a high electrical conductivity and mechanical strengths ay high temperatures. So It was considered a useful materials for nanosized device materials and added materials for strength hardening. Much methods were developed for SiC nanowire and nanorods like CVD, carbothermal reduction, Laser ablation and CNT-confined reduction. These methods used the VLS (Vapor-Liquid-Solid) growth mechanism. In these experiments, SiC nanowire was grown by SLS (Sold-Liquid-Solid) growth mechanism used Graphite substrate, And we characterized its microstructure to compare with VLS growth mechanism.

• Journal of the Korean Wood Science and Technology
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• 제33권5호통권133호
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• pp.92-98
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• 2005

This study was performed to get the basic information concerned to the optimum culture condition of Inonotus obliquus. Several solid media, PDA, MEA and Czapek-Dox, and three liquid media were adopted for the in vitro cultivation. Some main features of the fungal morphological characteristics under cultivation conditions were observed and described. Preliminary results showed that appearance of the mycelial mat, hyphal size and substrate pigmentation differed according to the media. The PDA medium was the most favorable substrate for the growth on solid culture, followed by MEA and Czapek-Dox media. Concerned to the addition of amino acids, 5 amino acids, such as alanine, alginine, isoleucine, leucine and threonine, enhanced to the mycelial growth. Isoleucine was shown the best fungal growth. An important morphological hyphal structure for the fungus, the setae, was found in abundance and diverse its shape and size. In liquid culture, fresh potato broth was the best growth stimulant of the fungus, followed by Malt extract and potato broth. Addition of yeast extract to the liquid media had improved the biomass, but not laccase production.

• 한국균학회지
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• 제42권1호
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• pp.40-49
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• 2014

우리나라 산림에서 수집한 목재부후성 버섯 균주들에 대한 배지 및 온도별 균사생장 특성을 고체평판배지 상에서 조사하였다. 대부분의 균주들은 malt extract agar (MEA)나 sabouraud dextrose agar (SDA)보다는 PDA (potato dextrose agar) 배지에서 균사 생장력이 더 높았다. 몇몇 균주들을 제외하고, 균주들의 대부분은 PDA 배지 상에서 배양 시 $25^{\circ}C$에서 가장 잘 생장하였으며, 고온($30^{\circ}C$)보다는 저온($10^{\circ}C$)에서 균사 생장이 저조하였다. 2종류의 서로 다른 세포외효소 활성에 각각 특이적으로 반응할 수 있는 기질이 함유된 고체평판배지 상에서 모든 시험균은 carboxymethyl cellulase 활성과 laccase 활성을 나타냈다.

• Journal of Information Display
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• 제10권2호
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• pp.76-79
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• 2009

In Joule-heating-induced crystallization, solid-to-solid or liquid-to-solid phase transformation could occur. It was found that novel physical phenomena that randomly nucleated liquid seeds, followed by rapid solidification in an amorphous matrix, during the Joule-heating-up period play an important role especially in liquid-to-solid transformation. Under some processing conditions, super-grains sized 6-8 ${\um}m$ were produced by the lateral growth from the initial seeds, without any artificially control.