• Title/Summary/Keyword: morphology formation

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Analysis of Filamentous Fungal Growth and Pellets Formation by Fractal Geometry (Fractal 기하학을 이용한 균사의 성장과 구체 형성의 특성 분석)

  • 류두현
    • KSBB Journal
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    • v.10 no.2
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    • pp.119-125
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    • 1995
  • The morphology of fungal growth, which is an important variable for separability and rheological property of fermented medium, was quantified with fractal geometry Fractal dimensions were determined for submerged growth of two industrially important fungi, Aspergillus niger and Aspergillus oruzae. The tendency of pellet formation was related to the fractal dimension of fungi.

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Electrochemical Synthesis of Octahedral Nanostructured PbF2

  • Lee, Joon-Ho;Choi, Jin-Sub
    • Bulletin of the Korean Chemical Society
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    • v.32 no.2
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    • pp.463-466
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    • 2011
  • In this work, we investigate anodization of Pb in ethylene glycol containing small amount of $NH_4F$, demonstrating that ${\beta}-PbF_2$ particles with octahedral morphology can be prepared by adjusting the applied potential and anodizing time. FE-SEM images and XRD measurements of anodic nanostructures as a function of anodizing time clearly show that PbO is first formed on Pb. Subsequently, a local dissolution of PbO leads to formation of skeleton structure of PbO, releasing $Pb^{2+}$ ions in the electrolyte. The lead ions can be precipitated on the walls or intersection of the skeleton walls when the concentration of lead ions is saturated. The method described in this article shows the feasibility of formation of metal fluoride crystal by anodization of metal in a fluoride containing solution.

Deposition Characteristics and Stability of Itaconate LB Films (이타코네이트계 LB막의 안정성 및 누적특성)

  • 신훈규;최용성;김은구;김경철;권영수;이범종;장정수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.11a
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    • pp.198-201
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    • 1994
  • Stability improvement of fragile LB films was attempted by polyion complexation of monolayers at the air-water interface and crosslinking of the resulting LB films. The spreading polymers were synthesized by radical copolymerization of monoalkyl itaconate with oligoethyleneglycol methyl vinylether, and poly(allylamine) was employed as the subphase polymer. Formation and characteristic of the monolayers were comfirmed by surface pressure-area($\pi$-A) isotherms. The two different polymers formed polyion-complexed monolayer through the formation of carboxylate/ammonium salt at the air-water interface. Y-type deposition occurred on solid substrates, and the transfer ratio was over 0.7. Pores (diameter, 0.1$\mu\textrm{m}$) of a membrane filter could be covered by polyion-complexed 6 layers. Interactions of the polymers with metal ions were investigated of the air-water interface and in the LB films. The structure change and macroscope morphology of the LB films were confirmed by FT-lR and SEM, respective1y.

New Retention System Using Branched Polymer

  • Son, Dong-Jin;Kim, Bong-Yong
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2006.06b
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    • pp.251-256
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    • 2006
  • The purpose of this study was to confirm multiple retention system of C-PAM, A-PAM and Inorganic micro particles vs. traditional micro particle system and dual polymer system by measuring retention, drainage and formation using RDA HSF and Techpap 2D -F Sensor The benefits of dual polymer system were easy to use, low chemical consumption and good retention property but defect was worse drainage property than inorganic microparticle systems. On the other hand, Inorganic microparticle system had benefit of good drainage effect but defects were difficult to use, high chemical consumption. Therefore, we tried to find optimal morphology of polyacrylamide and applied to multiple retention system of C-PAM, A-PAM and inorganic microparticles to compensate defects of both of retention systems. As a result, we found the performance of branched C-PAM, branched A-PAM and inorganic micro particle triple system was more appropriate than traditional inorganic mircoparticle systems or dual polymer systems by comparing retention, drainage and formation.

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Numerical Simulation of Particle Deposition Pattern on Cylindrical Fiber under External Electrical Field (외부 전기장내의 단일 섬유에 대한 먼지층 형사 수치 모사)

  • 박현설;정용원;박영옥;이규원
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.1
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    • pp.41-51
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    • 1999
  • In this study, the two dimensional morphology of particle accumulates on a cylindrical fiber was numerically simulated when a uniform external electric field was present across a cylindrical fiber. In order to investigate the mechanism of linear dendrite formation which is observed under the above electrostatic condition, the electrostatic forces between a newly introduced particle and each deposited particle were calculated and compared with those between the particle and fiber As a result of this study it was found that dielectrophoretic forces between the oncoming particle and fiber play principal roles in linear dendrite formation.

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Analysis of Filamentous Fungal Growth and Pellets Formation by Fractal Geometry (Fractal 기하학을 이용한 균사의 성장과 구체 형성의 특성 분석)

  • 류두현
    • KSBB Journal
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    • v.9 no.5
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    • pp.512-517
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    • 1994
  • The morphology of fungal growth, which is an important variable for separability and rheological property of fermented medium, was quantified with fractal geometry. Fractal dimensions were determined for submerged growth of two industrially important fungi, Aspergillus niger and Aspergillus oryzae. The tendency of pellet formation was related to the fractal dimension of fungi.

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Epidermis Proliferative Effect of the Panax ginseng Ginsenoside $Rb_2$

  • Choi, Seong-Won
    • Archives of Pharmacal Research
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    • v.25 no.1
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    • pp.71-76
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    • 2002
  • Ginseng has been used as a traditional medicine with various therapeutic effects. However, it is still unknown which component of this plant is effective at promoting wound healing. Recently, ginsenoside $Rb_2$ has been reported to improve wound healing. In this study, to investigate the reported wound healing effect of the ginsenoside $Rb_2$, cell morphology and protein factors involved in epidermal formation were evaluated by immunshemical and immunoblotting analysis. $Rb_2$ stimulated epidermal cell proliferation, and the cell showed a 1.5-fold increase in thymidine uptake compared to the control (p<0.05, n=3). Futheremore $Rb_2$, was found to stimulate epidermis formation in a dose-dependent manner in raft culture, and to dose dependently enhance the expressions of protein factors related to cell proliferation, namely, epidermal growth factor and its receptor, fibronectin and its receptor, keratin 5/14, and collagenase 1 (p<0.05, n=3~9). It is believed that ginsenoside $Rb_2$, enhances epidermal cell proliferation by upregulating the expressions of these proliferation-related factors.

Effect of the Mixed Electrolyte on the Film Growth and Corrosion Characteristics of Anodized Al 6061 Alloy (Al 6061 합금 양극산화피막의 성장과 부식특성에 미치는 혼합 전해용액의 영향)

  • Ryu, Han-Woong;Kim, Yong-Hwan;Chung, Uoo-Chang;Chung, Won-Sub
    • Korean Journal of Materials Research
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    • v.17 no.5
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    • pp.244-249
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    • 2007
  • The properties of anodized films on aluminum 6061 alloy in single electrolyte of sulfuric acid and mixed electrolyte of sulfuric-boric acid and sulfuric-boric-nitric acid have been studied. Polarization tests in NaC solution were used to investigate the corrosion performance. Characteristics of film formation and surface morphology were examined by optical microscopy, FE-SEM and EDS. The results obtained have indicated that oxide films growth have been promoted by nitric acid and anodized films in mixed electrolyte have superior corrosion resistance. In case of anodic films formed in mixed electrolyte, some grooves and numerous crazings were also observed at the surface.

Enhancement of Anti-tumorigenic Polysaccharide Production, Adhesion, and Branch Formation of Bifidobacterium bifidum BGN4 by Phytic Acid

  • Ku, Seock-Mo;You, Hyun-Ju;Ji, Geun-Eog
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.749-754
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    • 2009
  • The polysaccharide (BB-pol) extracted from Bifidobacterium bifidum BGN4 showed growth inhibitory effects on several colon cancer cell lines such as HT-29 and HCT-116. To increase the yield of polysaccharide, B. bifidum BGN4 was cultured in various culture media with different compositions. When B. bifidum BGN4 was cultured in modified MRS broth containing phytic acid, the cells showed increased branch formation and enlarged morphology. The content of total carbohydrate and the ability of adhesion to intestinal epithelial cells were also increased by phytic acid. The polysaccharide obtained from the cells grown in the presence of phytic acid inhibited the proliferation of cancer cell lines such as HT-29 and MCF-7 cells but not normal colon cell line, FHC. Taken together, Bifidobacterium grown in the presence of phytic acid may confer enhanced beneficial function for the host.

Formation of Rod-like $Al_2TiO_5$ via Mechanical Activation Followed by Thermal Processing

  • Chen, Xiaohu;Chen, Xiaomin;Zhao, Huang;Wud, Jihuai
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.163-164
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    • 2006
  • A QM-ISP-4 Planetary Mill was employed to activate mechanically the mixtures of anatase and corundum at room temperature for different times. The milled powder mixtures were then sintered at $1300^{\circ}C$ for 1 h. The XRD results showed that the milled powder mixtures were completely transformed into $Al_2TiO_5$ after sintering, except the mixtures milled for 5 and 10 hours. The SEM observations showed the typical morphology of rod-like $Al_2TiO_5$ vary in the range: widths from 0.6 to $1.2\;{\mu}m$, and lengths from 3.0 to $6.0\;{\mu}m$. The rod-like $Al_2TiO_5$ formation was attributed to the positive effects caused by the mechanical activation.

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