• 제목/요약/키워드: growth morphology

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영지의 액체배양 중 균사형태에 미치는 통기.교반의 영향 및 Scale-up (Effect of Agitation, Aeration and Scale-up on Mycelial Morphology During Liquid Culture of Ganoderma lucidum)

  • 이학수;이기영;최상윤;이신영
    • KSBB Journal
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    • 제26권4호
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    • pp.357-364
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    • 2011
  • This study was carried out to investigate the effects of agitation, aeration and scale-up on the mycelial growth, exo-polysaccharide (EPS) production, and mycelial morphology in the liquid culture of Ganoderma lucidum. A correlation between roughness and operating variables was also studied to scale-up the liquid culture of G. lucidum in a jar fermenter. When the agitation speed or aeration rate increased, the morphological form was changed from rough pellet to smooth pellet form. Increase of the agitation and aeration reduced the mycelial roughness. On the other hand, in the case of pellet size, it was not affected by aeration. The higher EPS production was obtained at approximately 17% of roughness and mycelial pellet size of 3~5 mm. The morphology at each fermenter was closely correlated with kLa value, and it was found that similarity of morphology would be used as a criteria of scale-up for liquid culture of G. lucidum.

Preparation of Alumina Powder with Special Morphology

  • Ma, Chicheng;Zhou, Xuesi;Zhu, Tun
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1997년도 Proceedings of the 12th KACG Technical Meeting and the 4th Korea-Japan EMGS (Electronic Materials Growth Symposium)
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    • pp.3-5
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    • 1997
  • Synthesis of ammonium aluminum hydrogen carbonate(AAHC) via reaction of aluminum bicarbonate and aluminum salt and thermal decomposition is oner of the important processes for preparation of high pure and ultra fine alumina. Kato and coworkers[1] developed this process, at same time Von Erdos and Altorfe[2] found AAHC in the corrosive products of aluminum in the atmosphere of carbon dioxide and ammonia. Murase and Iga[3] synthesized acicular AAHC in a autoclave under 60 to 12$0^{\circ}C$ Hayashi[4] optimized the conditions for preparation of AAHC and alumina. Attemp has been made in this paper to reveal the conditions affect the morphology of the synthesized AAHC and the consequently produced alumina.

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Pulsed laser ablation of hydroxyapatite in ethanol

  • Lee, Jung-Il;Ryu, Jeong Ho
    • 한국결정성장학회지
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    • 제24권5호
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    • pp.219-223
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    • 2014
  • Pulsed laser ablation in liquid medium was successfully employed to synthesize hydroxyapatite colloidal nanoparticles. The crystalline phase, particle morphology, size distribution and microstructure of the hydroxyapatite nanoparticles were investigated in detail. The obtained hydroxyapatite nanoparticles had spherical shape with sizes ranging from 5 to 20 nm. The laser ablation and the nanoparticle forming process were discussed with explosive ejection mechanism by investigating change of surface morphology on target. The analytical results of XPS, FT-IR and Raman spectroscopy confirms that the stoichiometry and bonding properties of the hydroxyapatite nanoparticles are in good agreement with reported bulk hydroxyapatite materials.

CIGS 박막 태양전지를 위한 CdS 버퍼층의 특성 연구 (Characteristics of CdS buffer layer for CIGS thin film solar cells)

  • 박미선;성시준;황대규;김대환;이동하;강진규
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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    • pp.394-396
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    • 2012
  • Chemical bath deposition (CBD) process conditions for depositing CdS buffer layers was studied for high efficiencies of CIGS thin film solar cells. Growth rate of CdS thin films has an effect on surface morphology and quality of thin films. By the change of growth rate, CdS buffer layers showed a large difference in surface morphology and this difference was closely related with the photovoltaic properties of CIGS solar cells.

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과수목(果樹木)의 역병(疫病)을 유발하는 Phytophthora cactorum의 유주자(遊走子)와 난포자(卵胞子)의 균사생장과 균총의 형태 (Growth Rate and Colony Morphology of Progenies of Zoospores and Oospores of Phytophthora cactorum causing Phytophthora rots in Apple Trees)

  • 심재욱;이민웅
    • 한국균학회지
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    • 제22권4호
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    • pp.281-285
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    • 1994
  • Phytophthora cactorum으로부터 분리된 유주자(遊走子)는 균사 생장이 상대적으로 균일하고 균사 생장분포가 모체(母體) 균주(菌株)와 유사하였으나, 분리된 난포자(卵胞子)는 균사생장분포가 매우 다양하였다. 또한, 균총의 특징은 난포자에서 크게 다양한 반면, 유주자에서는 균일하였다. 이 결과는 P. cactorum의 균사생장과 균총의 모양을 결정하는데 있어 다양한 유전자가 관여하고 있으며, 몇몇 역병균이 생장하는 동안에 이배체성 생식을 나타낼 수 있다는 점을 시사한다.

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XPS Characterization and Morphology of MgO Thin Films grown on Single-Crystalline Diamond (100)

  • Lee, S.M.;Ito, T.;Murakami, H.
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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    • pp.19-27
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    • 2003
  • Morphology and composition of MgO films grown on single-crystalline diamond (100) have been studied. MgO thin films were deposited in the substrate temperature range from room temperature (RT) to 723K by means of electron beam evaporation using MgO powder source. Atomic force microscopy images indicated that the film grown at RT without $O_2$ supply was relatively uniform and flat whereas that deposited in oxygen ambient yielded higher growth rates and rough surface morphologies. X-ray photoelectron spectroscopy analyses demonstrate that the MgO film deposited at RT without $O_2$ has the closest composition to the stoichiometric MgO, and that a thin contaminant layer composed mainly of magnesium peroxide (before etching) or hydroxide (after etching) was unintentionally formed on the film surface, respectively. These results will be discussed in relation to the interaction among the evaporated species and intentionally supplied oxygen molecules at the growth front as well as the interfacial energy between diamond and MgO.

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Morphologically Controlled Growth of Aluminum Nitride Nanostructures by the Carbothermal Reduction and Nitridation Method

  • Jung, Woo-Sik
    • Bulletin of the Korean Chemical Society
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    • 제30권7호
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    • pp.1563-1566
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    • 2009
  • One-dimensional aluminum nitride (AlN) nanostructures were synthesized by calcining an Al(OH)(succinate) complex, which contained a very small amount of iron as a catalyst, under a mixed gas flow of nitrogen and CO (1 vol%). The complex decomposed into a homogeneous mixture of alumina and carbon at the molecular level, resulting in the lowering of the formation temperature of the AlN nanostructures. The morphology of the nanostructures such as nanocone, nanoneedle, nanowire, and nanobamboo was controlled by varying the reaction conditions, including the reaction atmosphere, reaction temperature, duration time, and ramping rate. Iron droplets were observed on the tips of the AlN nanostructures, strongly supporting that the nanostructures grow through the vapor-liquid-solid mechanism. The variation in the morphology of the nanostructures was well explained in terms of the relationship between the diffusion rate of AlN vapor into the iron droplets and the growth rate of the nanostructures.

SM490A 재질 필렛 용접시편의 피로수명과 용접부 피로파단시 스트레인 변화 연구 (A study on the fatigue life and the change of the strain during the fatigue fracture on the fillet welded specimens of SM490A)

  • 김재훈;구병춘
    • 한국철도학회논문집
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    • 제7권4호
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    • pp.345-349
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    • 2004
  • This study investigates the fatigue lives of SM490A material(base metal) specimens and fillet weld specimens, which are made same material and weld method for the railway vehicle. These fatigue lives have a difference, the fatigue lives of weld specimen are shorter than those of base metal. We measured the strains on the weld positions of the specimens during the fatigue test for investigation of crack initiation and crack growth. In these result, we could find the information of the crack initiation position on weld bead and the history of crack growth. Also we knew that the fatigue crack initiation cycles and the changes of the strain which were affected the fractured surface roughness and morphology.

Cellular Adhesion and Growth on the Vertically Aligned Silicon Nanowire Arrays

  • 윤서영;박이슬;이진석
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.266.2-266.2
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    • 2013
  • According to advanced nanotechnology, the nanostructured materials with various kinds and shape are synthesized easily or produced by process. Recently, researches about interaction between the nanostructured materials and biological system have been progressed actively. The surface topography may influence cellular responses, for example cell adhesion, cell morphology. In this work, we synthesized vertically aligned silicon nanowires (SiNWs) on the Au-covered Si(111) wafer by chemical vapor deposition (CVD) method. We accomplished to control of the SiNWs diameter by regulating thickness of Au film such as 1 nm and 10 nm. These substrates did not isolate cells and just provided surface topography for cell culture. Human Embryonic Kidney 293T cells (HEK 293T cells) were cultured on these substrates for 2 days. We studied the nanotopographical effects on cell morphology, adhesion, and growth which are evaluated on each SiNWs substrate comparing bare glass as control.

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바텀업 기반의 반도체 나노와이어 합성방법 및 응용소자 연구 (Application of Semiconductor Nanowires Based on Bottom-up Growth)

  • 이원우;양동원;박원일
    • 진공이야기
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    • 제3권3호
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    • pp.10-14
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    • 2016
  • Semiconductor nanowires (NWs) refer to one-dimensional semiconductor materials that have a diameter constrained to tens of nanometers or less and an unconstrained length. Over the past few decades, most efforts in the semiconductor NWs have been focused on synthesis, structure and morphology control, and assembly, as appropriate for diverse functional device applications. This paper provides a detailed overview of the recent research activities and major achievements in nanowire research, which especially includes nanowires synthesis, position and direction-controlled assembly or growth. In addition, the fine tuning of structure and morphology, and the related properties and device applications of the NWs are highlighted.