• Title/Summary/Keyword: growth conditions

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Deposition of Epitaxial Silicon by Hot-Wall Chemical Vapor Deposition (CVD) Technique and its Thermodynamic Analysis

  • Koh, Wookhyun;Yoon, Deoksun;Pa, ChinHo
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1998년도 PROCEEDINGS OF THE 14TH KACG TECHNICAL MEETING AND THE 5TH KOREA-JAPAN EMGS (ELECTRONIC MATERIALS GROWTH SYMPOSIUM)
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    • pp.173-176
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    • 1998
  • Epitaxial Si layers were deposited on n- or p-type Si(100) substrates by hot-wall chemical vapor deposition (CVD) technique using the {{{{ {SiH }_{ 2} {Cl }_{2 } - {H }_{ 2} }}}}chemistry. Thermodynamic calculations if the Si-H-Cl system were carried out to predict the window of actual Si deposition procedd and to investigate the effects of process variables(i.e., the deposition temperature, the reactor pressure, and the source gas molar ratios) on the growth of epitaxial layers. The calculated optimum process conditions were applied to the actual growth runs, and the results were in good agreement with the calculation. The expermentally determined optimum process conditions were found to be the deposition temperature between 900 and 9$25^{\circ}C$, the reactor pressure between 2 and 5 Torr, and source gad molar ration({{{{ {H }_{2 }/ {SiH }_{ 2} {Cl }_{2 } }}}}) between 30 and 70, achieving high-quality epitaxial layers.

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The culture conditions for the mycelial growth of Auricularia auricula-judae

  • Jo, Woo-Sik;Kim, Dong-Geun;Seok, Soon-Ja;Jung, Hee-Young;Park, Seung-Chun
    • 한국버섯학회지
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    • 제12권2호
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    • pp.88-95
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    • 2014
  • Auricularia auricula-judae is an edible mushroom, which is known as wood ear, free ear, black ear mushroom, and free jelly fish. This study was carried out to obtain the basic information for mycelial culture conditions of Auricularia auriculajudae. According to colony diameter and mycelial density, the media for suitable mycelial growth were PDA and MCM. The optimum temperature for mycelial growth was $25{\sim}30^{\circ}C$. Carbon and nitrogen sources were mannose and malt extract, respectively. The optimum C/N ratio was in the range of 10 to 1 with 2% glucose. Other minor components for the optimal growth were thiamine-HCl and biotin as vitamins, succinic acid and lactic acid as organic acids, and $MgSO_4{\cdot}7H_2O$ and $KH_2PO_4$ as mineral salts.

RESPONSES TO MONENSIN AND OESTRADIOL IN STEERS GRAZING TWO TROPICAL PASTURES IN N. E. QUEENSLAND

  • Jones, R.J.;Minson, D.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제3권3호
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    • pp.183-186
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    • 1990
  • Monensin administered as a slow release capsule to Droughtmaster steers grazing mixed pastures containing Stylosanthes hamata or grass pastures fertilized with N, had no effect on growth rate over 111 day period. Monensin significantly increased the level of propionic acid (p<0.001) and decreased the level of butyric acid (p<0.01) in the rumen. The lack of response to monesin was partly attributed to the poor pasture conditions and growth rate of the steers during part of the experimental period. An implant of oestradiol improved growth rates during the period of poor forage quality and in the subsequent 56 days when pastures were of high quality following rain. Mean growth rates over the entire 157 days for control, monensin and monensin/oestradiol treatments were 0.37, 0.37 and 0.50 kg/d respectively. It was concluded that when pasture conditions are sufficient only for the maintenance of liveweight, production can be improved by an oestradiol implant but not by feeding an ionophore such as monensin.

Enhancement of UV-induced nucleotide excision repair activity upon forskolin treatment is cell growth-dependent

  • Lee, Jeong-Min;Park, Jeong-Min;Kang, Tae-Hong
    • BMB Reports
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    • 제49권10호
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    • pp.566-571
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    • 2016
  • Forskolin (FSK), an adenylyl cyclase activator, has recently been shown to enhance nucleotide excision repair (NER) upon UV exposure. However, our study revealed that this effect was detected in human skin epithelial ARPE19 cells only in growing cells, but not in non-cycling cells. When the cells were grown at low density (70% confluence), FSK was capable of stimulating cAMP responsive element binding (CREB) phosphorylation, a marker for FSK-stimulated PKA activation, and resulted in a significant increase of NER activity compared to control treatment. However, cells grown under 100% confluent conditions showed neither FSK-induced CREB phosphorylation nor the resulting NER enhancement. These findings indicate that cellular growth is critical for FSK-induced NER enhancement and suggest that cellular growth conditions should be considered as a variable while evaluating a reagent's pharmacotherapeutic efficacy.

Ti-6A1-4V 합금의 피로거동에 미치는 온도, 주파수 및 미세조직의 영향 (The Effect of Temperature, Frequency and Microstructure on Fatigue Crack Propagation in Ti-6A1-4V Alloy)

  • 김현철;김승한;임병수;김두현;이용태
    • 한국자동차공학회논문집
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    • 제4권1호
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    • pp.198-207
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    • 1996
  • The effect of temperature, frequency and microstructure on fatigue crack propagation property of Ti-6A1-4V alloy has been investigated. The temperatures employed were room temperature, 20$0^{\circ}C$ and 40$0^{\circ}C$. The frequencies were 20Hz and 8 Hz. The microstructures tested were equiaxed and bimodal microstructures. Mechanical properties and fatigue crack growth rates were measured in different test conditions. From the experimental results, following conclusions were obtained. Bimodal microstructure showed superior fatigue crack growth resistance to equiaxed microstructure. Under all test conditions, fatigue crack growth rate increased with test temperature. Wine the frequency decreasing from 20Hz to 8Hz, fatigue crack growth rate increased.

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Ginkgo biloba 세포배양에서 배지 및 배양조건이 세포성장 및 Flavonol Glycosides 생합성에 미치는 영향 (Effects of Nutrients and Culture Conditions on the Cell Growth and the Flavonol Glycosides Production in Cell Cultures of Ginkgo biloba)

  • 이원규;유연우변상요정헌관
    • KSBB Journal
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    • 제8권1호
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    • pp.55-61
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    • 1993
  • Ginkgo biloba의 세포배양을 통하여 세포성장과 flavonol glycosides의 생성에 영향을 미치는 여러 조건들을 연구하였다. 다양한 지역으로부터 유도된 세포주들의 세포성장과 flavonol glycosides의 생합성 능력은 서로 차이가 있었다. 이들의 캘러스 및 현탁 세포는 배지조건과 배양조건에 따라 성장 및 f1avonol glycosides 생합성에 많은 영향을 받았었다. 특히 배양조건 중 빛의 영향은 현저하여 명조건에서의 f1avonol glycosides의 생성은 암조건보다 10배 이상 증가함을 알 수 있었다.

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III-V 족 MOCVD 공정의 열전달 및 필름 성장에 대한 연구 (A Study on the Heat Transfer and Film Growth During the III-V MOCVD Processes)

  • 임익태
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1213-1218
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    • 2004
  • Film growth rate of InP and GaAs using TMI, TMG, TBA and TBP is numerically predicted and compared to the experimental results. Obtained results show that the film growth rate is very sensitive to the thermal condition in the reactor. To obtain exact thermal boundary conditions at the reactor walls, we analyzed the gas flow and heat transfer in the reactor including outer tube as well as the inner reactor parts using a full three-dimensional model. The results indicate that the exact thermal boundary conditions are important to get precise film growth rate prediction.

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Optimal Culture Conditions for Mycelial Growth and Exo-polymer Production of Ganoderma applanatum

  • Jeong, Yong-Tae;Jeong, Sang-Chul;Yang, Byung-Keun;Islam, Rezuanul;Song, Chi-Hyun
    • Mycobiology
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    • 제37권2호
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    • pp.89-93
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    • 2009
  • The effect of fermentation parameters and medium composition on the simultaneous mycelial growth and exo-polymer production from submerged cultures of Ganoderma applanatum was investigated in shake-flask cultures. The optimum initial pH for mycelial growth and exo-polymer production was 5.0 and 6.0, respectively. The optimum temperature was $25^{\circ}C$ and the optimum inoculum content was 3.0% (v/v). The optimal carbon and nitrogen sources were glucose and corn steep powder, respectively. After 12 days fermentation under these conditions, the highest mycelial growth was 18.0 g/l and the highest exo-polymer production was 3.9 g/l.

배지와 배양조건이 검은비늘버섯의 균사생장에 미치는 영향 (Effect of Cultural Media and Conditions on the Mycelial Growth of Pholiota adiposa)

  • 이병석;서건식;이종수
    • 현장농수산연구지
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    • 제7권1호
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    • pp.74-80
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    • 2005
  • 검은비늘버섯의 균사체와 기능성 물질 대량생산을 목적으로 배지의 종류, 배양온도, 배양중의 진탕 유무가 균사생장에 미치는 영향을 조사한 결과 균사생장 최적배지는 MCM, 최적온도는 25℃로 밝혀졌고 진탕배양을 하였을 경우 정치배양보다 약 2~3배의 균사생장을 보였다.

Simultaneous growth of graphene and vertically aligned single-walled carbon nanotubes at low temperature by chemical vapor deposition

  • Hong, Suck Won;Kim, Kwang Ho;Jung, Hyun Kyung;Kim, Daesuk;Lee, Hyung Woo
    • Journal of Ceramic Processing Research
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    • 제13권spc1호
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    • pp.154-157
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    • 2012
  • We present the simultaneous growth of single-walled carbon nanotubes and graphene with the optimal conditions of the synthesizing parameters. The dense and vertically aligned SWNTs having the length of over 100 ㎛ was grown by 2 nm-thick Fe catalytic layer. From 650 ℃, the vertically well-grown SWNTs were obtained by increasing the temperature. The severallayered graphene was synthesized with the gas mixing ratio of 15 : 1(H2 : C2H2) at 650 ℃ and higher temperatures. With these optimal conditions, the vertically well-grown SWNTs and the several-layered graphene were synthesized simultaneously. The presence of SWNTs and the layer of graphene were verified by field emission scanning electron microscopy and high resolution transmission electron microscopy. From the result of this simultaneous synthesizing approach, the possibility of one step growth process of CNTs and grapheme could be verified.