• Title/Summary/Keyword: Solid-phase

검색결과 3,143건 처리시간 0.027초

Preparation of PVDF Membrane by Thermally-Induced Phase Separation

  • Heo, Chi-Haeng;Lee, Kyung-Mo;Kim, Jin-Ho;Kim, Sung-Soo
    • Korean Membrane Journal
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    • 제9권1호
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    • pp.27-33
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    • 2007
  • PVDF membrane formation via TIPS was performed for PVDF/DBP and PVDF/DMP systems. PVDF/DBP system showed solid-liquid phase separation behavior, while PVDF/DMP system has liquid-liquid phase separation characteristic as well as solid-liquid phase separation characteristic. PVDF contents and cooling conditions had great influence on structure, and the effects of each parameter were examined. Spherulitic structure was obtained due to the dominant PVDF crystallization. Diluent rejected to the outside of spherulite occupied the surface of the PVDF spherulites to result in the microporous spherulite formation and micro-void between spherulites. PVDF/DMP system had competitive solid-liquid and liquid-liquid phase separation depending on the cooling path.

Characterization of Adsorbents for the Solid-Phase Extraction of Trace Ibuprofen from Biological Samples (생체시료로부터 미량 이부푸로펜의 고상추출에 사용될 흡착제들의 특성)

  • Kim, Kyoung-Rae;Shim, Weon-Hee
    • YAKHAK HOEJI
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    • 제36권6호
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    • pp.563-569
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    • 1992
  • The sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of ibuprofen from biological samples. Chromosorb 107 gave the highest dynamic adsorption coefficient. Among the organic solvents examined, acetone gave the highest desorption coefficient. Using the Chromosorb 107 column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of ibuprofen. The usefulness of Chromosorb 107 as the solid adsorbent and acetone as the eluting solvent was examined for the solid-phase extraction of ibuprofen from serum in the concentration range of $20{\sim}40\;{\mu}g/ml$.

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TRANSIENT SIMULATION OF SOLID PARTICLE DISTRIBUTION WITH BAFFLES DESIGN PARAMETERS IN A STIRRED TANK (배플 형상에 따른 교반기 내부 고체입자 분포의 비정상상태 해석)

  • Kim, Chi-Gyeom;Won, Chan-Shik;Hur, Nahm-Keon
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 학술대회
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    • pp.171-175
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    • 2008
  • In the present study, a numerical simulations are investigated in a stirred solid/liquid system by using Eulerian multi-phase model. The transient flow field of liquid phase and distribution of solid particles are predicted in stirred tanks consisting of 4-pitched paddles impeller and baffles. The effects of number and width of baffles on the mixing time and the quality of solid suspension in a stirred tank are presented numerically. The result shows that the mixing time decreases as the width and number of baffles increase.

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A Flow Field Analysis of Compound Jets Modified at a 10 Degree Upward Angle ($10^{\circ}$상향분사된 혼합분류의 유동장 해석)

  • 박상규;이용호
    • Journal of Advanced Marine Engineering and Technology
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    • 제24권5호
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    • pp.103-110
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    • 2000
  • A two phase compound jet, which mixes pulverized solid particles with the air in the test section, is experimentally analyzed in this study. Two phase flow is jetted 10 degree upward in the primary jet, while the secondary jet utilizes the air only. The height difference between the primary and secondary central axises is 32.5mm. The velocity vector field, concentration field, and turbulent properties of solid particles are measured by using 3-Dimensional Particles Dynamics Analyzer. When the jet angle of the secondary jet goes into effect, the solid particle recirculation zone becomes larger. Also, solid particle concentration becomes more dense due to a velocity decrement of particles.

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Study on Two Phase Flow of Two Jets Existing Velocity Difference (속도차가 존재하는 두 분류의 2상유동에 관한 연구)

  • 양희천
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권4호
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    • pp.515-521
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    • 1998
  • In this study the mixing process of two-phase flow which makes two jets existing vlocity difference are analyzed. The primary jet is jetted on the condition of the state mixed pulverized solid pariticle with air and the velocity in the secondary jet is changed into three kinds velocities(0.60, 75m/s) The velocity vector field concentration field and turbulent properties of solid particles are measured by using 3-Dimensional Particles Dynamics Analyzer. As the velocity of secondary jet increases the solid particle recirculation zone becomes larger. Also solid particle concentration gets dense due to velocity decrement of particles.

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Characterization of Adsorbents for the Solid-Phase Extraction of Trace Diphenylhydantoin from Biological Samples (생체시료로 부터 미량 디페닐히단토인의 고상추출에 사용될 흡착제의 특성)

  • Kim, Kyoung-Rae;Lee, Kyoung-Won;Shim, Weon-Hee
    • YAKHAK HOEJI
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    • 제36권2호
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    • pp.120-125
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    • 1992
  • Ths sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of diphenylhydantoin from biological samples. Graphitized carbon black(GCB) gave the highest adsorption coefficient. And among the organic solvents examined, methanol gave the highest desorption coefficient. Using the GCB column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of diphenylhydantoin. The usefulness of GCB as the solid adsorbent was examined for the solid-phase extraction of diphenylhydantoin from serum in the concentration range of $20-50\;{\mu}g/ml$.

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Surface Polarity Dependent Solid-state Molecular Biological Manipulation with Immobilized DNA on a Gold Surface

  • Lee, Jiyoung;Kim, Jeong Hee
    • International Journal of Oral Biology
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    • 제37권4호
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    • pp.181-188
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    • 2012
  • As the demand for large-scale analysis of gene expression using DNA arrays increases, the importance of the surface characterization of DNA arrays has emerged. We compared the efficiency of molecular biological applications on solid-phases with different surface polarities to identify the most optimal conditions. We employed thiol-gold reactions for DNA immobilization on solid surfaces. The surface polarity was controlled by creating a self-assembled monolayer (SAM) of mercaptohexanol or hepthanethiol, which create hydrophilic or hydrophobic surface properties, respectively. A hydrophilic environment was found to be much more favorable to solid-phase molecular biological manipulations. A SAM of mercaptoethanol had the highest affinity to DNA molecules in our experimetns and it showed greater efficiency in terms of DNA hybridization and polymerization. The optimal DNA concentration for immobilization was found to be 0.5 ${\mu}M$. The optimal reaction time for both thiolated DNA and matrix molecules was 10 min and for the polymerase reaction time was 150 min. Under these optimized conditions, molecular biology techniques including DNA hybridization, ligation, polymerization, PCR and multiplex PCR were shown to be feasible in solid-state conditions. We demonstrated from our present analysis the importance of surface polarity in solid-phase molecular biological applications. A hydrophilic SAM generated a far more favorable environment than hydrophobic SAM for solid-state molecular techniques. Our findings suggest that the conditions and methods identified here could be used for DNA-DNA hybridization applications such as DNA chips and for the further development of solid-phase genetic engineering applications that involve DNA-enzyme interactions.