• Title/Summary/Keyword: electrophoretic method

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Electrophoretic variations of enzyme, GDH (NADP-dependent glutamate dehydrogenase)(EC. 1.4.1.4) in characterizing clones and isolates of Malaysian Plasmodium falciparum

  • Ang, Hooi-Hoon;Chan, Kit-Lam;Mak, Joon-Wah
    • Parasites, Hosts and Diseases
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    • v.34 no.3
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    • pp.211-213
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    • 1996
  • Malaysian, Ajricn and Thai PZQsmodiumJnkipamm isolates were cultured in uiko by the Tracer and Jensen method (1976, 1977) and were later cloned by the limiting dilution method (Rosario, 1981), Forty-eight clones were obtained and were characterized by electrophoretic variations of GDH (NADP-dependent glutamate dehydrogenase)(EC. 1.4.1.4). It was found that they were pure clones because they possessed either GDH-1 or GDH-2 unlike their parent isolates which exhibited both GDH-1 and GDH-2.

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Fabrication of YBCO Superconducting Thick Film by Use of Lateral Shaky Field Assisted EPD Method (측면진동보조전계 전기영동 전착방식을 적용한 YBCO 초전도 후막의 제작)

  • 소대화;전용우
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.11
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    • pp.1041-1046
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    • 2003
  • In order to improve the surface uniformity and the conduction properties of the fabricated YBCO thick films, a system that applies alternating field vertically to the EPD field has been developed for the first time and applied to the electrophoretic deposition process. The applied alternating electric field, so called Shaky Alternating Assisted Field, caused a force to be exerted on each YBCO particle and resulted in a shaking of the particle in the direction of applied electric field, accomplishing a uniform particle orientation. The usual commercial electrical power was used for the vertically applied alternating voltage and the induced electric field was 25-120 V/cm at 60Hz. The thick film fabricated by the method developed in this paper showed better surface uniformity without crack and porosity and improved film characteristics such as critical temperature (Tc,zero = 90 K) and critical current density (2354 A/$\textrm{cm}^2$), Therefore, it is expected that the shaky-aligned electrophoretic deposition method can be used to fabricate superconductor films through a simpler process and at less expense.

Field emission properties of carbon nanotubes grown on micro-tip substrates using an electrophoretic deposition method (미세 팁 기판 위에 전기영동법으로 성장시킨 탄소 나노튜브의 전계방출 특성)

  • Chang, Han-Beet;Noh, Young-Rok;Kim, Jong-Pil;Park, Jin-Seok
    • Journal of the Semiconductor & Display Technology
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    • v.9 no.4
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    • pp.7-12
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    • 2010
  • Field-emission characteristics of carbon nanotubes(CNTs), which were grown on conical-type tungsten micro-tips by using an electrophoretic deposition(EPD) method, were examined. The EPD method proved to be convenient to manipulate and arrange CNTs from well dispersed suspensions onto such tip-type substrates. The growth rate of CNTs was proportional to the applied d.c. bias voltage and the process time. It was observed from the Raman study that the EPDproduced CNTs showed better crystal qualities with the Raman intensity ratio( $I_D$/$I_G$) of 0.41-0.42 than the CVD-produced CNTs and their crystal qualities could be further improved by thermal annealing. The electron emitters based on the EPDCNTs showed excellent field emission properties, such as the threshold voltage for electron emission of about 620 V and the maximum emission current of about 345 ${\mu}A$. In addition, the EPD-CNTs exhibited the stable long-term(up to 40 h) emission capability and the emission stability was enhanced by thermal annealing.

Electrophoretic Deposition for the Growth of Carbon nanofibers on Ni-Cu/C-fiber Textiles

  • Nam, Ki-Mok;Mees, Karina;Park, Ho-Seon;Willert-Porada, Monika;Lee, Chang-Seop
    • Bulletin of the Korean Chemical Society
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    • v.35 no.8
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    • pp.2431-2437
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    • 2014
  • In this study, Ni, Ni-Cu and Ni/Cu catalysts were deposited onto C-fiber textiles via the electrophoretic deposition method, and the growth characteristics of carbon nanofibers on the deposited catalyst/C-fiber textiles were investigated. The catalyst deposition onto C-fiber textiles was accomplished by immersing the C-fiber textiles into Ni or Ni-Cu mixed solutions, producing the substrate by post-deposition of Ni onto C-fiber textiles with pre-deposited Cu, and passing it through a gas mixture of $N_2$, $H_2$ and $C_2H_4$ at $700^{\circ}C$ to synthesize carbon nanofibers. For analysis of the characteristics of the synthesized carbon nanofibers and the deposition pattern of catalysts, SEM, EDS, BET, XRD, Raman and XPS analysis were conducted. It was found that the amount of catalyst deposited and the ratio of Ni deposition in the Ni-Cu mixed solution increased with an increasing voltage for electrophoretic deposition. In the case of post-deposition of Ni catalyst onto substrates with pre-deposited Cu, both bimetallic catalyst and carbon nanofibers with a high level of crystallizability were produced. Carbon nanofibers yielded with the catalyst prepared in Ni and Ni-Cu mixed solutions showed a Y-shaped morphology.

Synthesis and Characterization of Graphene Counter Electrode By Electrophoretic Deposition for Dye-Sensitized Solar Cells

  • Choe, Yun-Su;Gong, Jae-Seok;Choe, Hyeon-Gwang;Jeon, Min-Hyeon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.160-160
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    • 2013
  • Dye-sensitized solar cells (DSSCs) have attracted much attention because of their moderate light-to-electricity conversion efficiency, easy fabrication, and low cost. At present, platinum (Pt) is used as a counter electrode in DSSCs. However, it is found that Pt dissolves in iodide electrolyte solutions and creates chemical compound such as PtI4 and H2PtI6. Carbon based materials are one of candidates for a counter electrode of DSSCs. We prepare two types of graphite oxides by different chemical treatments; original graphite oxide, hydrazine treated graphite oxide. Each graphite oxide and magnesium nitrate dispersed in deionized water are prepared as solutions for electrophoretic deposition (EPD). Each graphite oxide electrode is deposited on fluorine-doped tin oxide (FTO) substrate by EPD method. Structural and electrochemical properties of each electrode are investigated by field-emission scanning electron microscopy and electrochemical impedance spectroscopy, respectively.

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Microcapsulation Technique of the Black and White Particles Suspension for Electrophoretic Display

  • Kim, Chul-Am;Jeong, Meyoung-Ju;Ahn, Seong-Deok;Kang, Seung-Youl;Lee, Yong-Eui;Suh, Kyung-Soo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.509-511
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    • 2003
  • We present a microcapsule manufacturing technique, which contains a polymer coated white $TiO_2$ and black particles suspension as the core material for a electrophoretic display ink, via the in-situ polymerization method using melamine? formaldehyde as a wall material. The obtained capsules have $50 {\sim} 300 {\mu}m$ of the diameter range. They show a good mechanical strength and thermal and optical property. We fabricate the microcapsules to the single layer to test the black/white electrophoretic display application.

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Preparation of Y-Ba-Cu-O Superconducting Film on Ag Substrate by an Electrophoretic Deposition Method

  • Kang Cheol-Hwa;Jeong Cheol-Mo;Yi Cheol-Woo;Kim Keon
    • Bulletin of the Korean Chemical Society
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    • v.15 no.1
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    • pp.20-22
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    • 1994
  • The preparation of $YBa_2Cu_4O_8$ thick film on Ag substrate by electrophoretic deposition was directly studied. Electrophoretic deposition was carried out in solution, which was composed of presintered $YBa_2Cu_4O_8$ powder, sodium, and 2-propanol as a solvent. The deposited thick films were heat-treated in $O_2$ at 815$^{\circ}$C for 12 hours and at 450$^{\circ}$C for 12 hours. We succeeded in obtaining superconducting $YBa_2Cu_4O_8$ films on Ag substrate. Even though the chemical reactions at the $YBa_2Cu_4O_8$/Ag interface occurred in the range of 10 ${\mu}$m, superconductivity was not depressed. The thickness of the films was in the range of 60-80 ${\mu}$ m. The characteristics of the films were examined by electric resistance measurements, X-ray diffraction, and SEM observations.

Electrophoretic characterization of Hollow Titania Sphere for E-paper display

  • Lee, J.Y.;Kim, T.H.;Kwon, Y.K.;Choi, H.J.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07a
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    • pp.321-323
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    • 2005
  • We report a microcapsule-based electronic ink display technique, containing hollow titania particles which were prepared via a complex coacervation method using gelatin and gum arabic. In order to reduce density mismatch between nanoparticels and dielectric medium, hollow titania particles were introduced. Microcapsules were then prepared using gelatin to improve the elasticity of the microcapsule wall and their electrophoretic characteristics were $investigated^1$

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Enantiomeric Profiling Analysis of NSAIDs by Capillary Electrophoresis Using TM $\beta$-Cyclodextrin as the Chiral Selector

  • Kim, Ji-Young;La, Sookie;Kim, Jung-Han;Kim, Kyoung-Rae
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.400.1-400.1
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    • 2002
  • Because of the differences in pharmacological properties between enantiomers of chiral acidic non-steroidal antiinflammatory drugs (NSAIDs) in human body. accurate determinations of their optical purities have been in great need. An efficient capillary electrophoretic (CE) profiling method was developed for the enantioseparation of NSAIDs. Capillary electrophoretic conditions were optimized using TM$\beta$-cyclodextrin as the chiral selectors under MES buffer. (omitted)

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Effect of applied Field on YBCO Superconductor in EPD Method (전기영동전착에서 YBCO 초전도 후막의 인가전계 영향)

  • Soh, Dea-Wha;Jeon, Yong-Woo;Choi, Sung-Jai;Park, Jung-Cheul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.63-66
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    • 2003
  • The electrophoretic deposition method has the advantage of relatively few fabrication facilities and simple process procedure as well as the economical and technical merit of allowing various forms of deposition and easy control of deposition thickness and wire length. A study, especially electric field and additive, on the optimization method to increase the density of particles and uniformity of their orientation have been performed to overcome the cracking and the porosity problems in the fabricated superconductor.

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