• Food Science and Preservation
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• v.13 no.5
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• pp.555-562
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• 2006

This study was conducted to investigate the rheological properties of protein-bound polysaccharide powders (SD-1, 2, 3) using ultrafiltration (UF) and spray drying (SD) process from Agaricus blazei Murill. The calculated weight-average molar mass (Mw) in the positions at 29.7 mL (for SD-1), and at 27.8 mL (for SD-2), and at 18.7 mL (for SD-3) was $8.2{\times}10^3,\;9.6{\times}10^4$, and $5.9{\times}10^6g/mol$, respectively. As concentration increased the solution showed higher pseudoplasticity where the pseudoplasticity decreased as temperature increased. The flow behaviors of spray dried powder solutions were more fitted to Herschel-Bulkley equation than Power law equation. Apparent viscosity of SD-2 was more temperature-dependent than that of SD-1 and 3. However, the SD-3 tended to be more concentration-dependent than SD-1 and 2 as temperature increasing.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.1
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• pp.30-35
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• 2000

The experimental study on the lift-off height of diffusion flames was conducted to investigate the damage of swirl-coaxial injector used in $GO_2$/kerosene rocket engine during initial stage of ignition. To investigate the causes of damage and to prevent further damage of the injector, experimental injector was designed and hot fire tests were performed with varying propellant momentum ratio($\frac{Momentum of {GO_2}}{Momentum of Kerosene}$) from 1 to 12. In experimental coaxial injector, kerosene is sprayed from the central nozzle with swirl and $GO_2$ sprayed around the kerosene nozzle in the direction parallel to the axis of combustion chamber. Chamber pressure are close to the atmospheric condition. Lift-off height was measured by still images from camcoder and average values were used as data.

• Clean Technology
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• v.25 no.1
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• pp.19-32
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• 2019

As regional air pollution gets worse by the sulfur oxides emitted from various types of vessels passing through the many countries, the International Maritime Organization establishes the emission control areas and regulates sulfur dioxide in those areas. In order to satisfy these regional regulations, the fuel selection method and the exhaust gas post-treatment device are applied to the ships. Due to the economic reasons, the post-treatment method of exhaust gas for reducing the amount of sulfur oxides discharged is mainly preferred. The scrubber which is dominantly used in the ships are the spray type system where the sprayed liquid drops used for capturing the soluble sulfur dioxides in the exhaust gas. The performance of the spray type system depends on the size distribution of the sprayed droplets. In order to evaluate this performance, we designed counterflow type scrubber and cyclone scrubber and evaluated the desulfurization efficiency and the amount of droplet evaporation according to the size of each droplet by using computational fluid dynamics. The Eulerian-Eulerian analysis method was used because the scrubber had a gas-liquid two-phase flow inside the scrubber. When the diameter of the droplet was $100{\mu}m$, $300{\mu}m$, $500{\mu}m$ and $700{\mu}m$. As a result, both of scrubbers showed high desulfurization efficiency and low evaporation amount at $500{\mu}m$ and $700{\mu}m$.

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.3
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• pp.9-15
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• 1999

The Analysis of spray characteristics for combined spray group are necessary to develop large rocket engine. In this study, basic effects of interaction from spray fan formed by impinging jets were investigated with respect to mass distribution, droplet velocities and diameter. Patternater and PDPA are used for experimental apparatus. Water was used as a test fluid When momentum ratio is 1, effect of interaction from collision of spray fan on mass distribution are small. Also, effect of interaction from collision of spray fan on droplet velocities and diameter are small. But, droplet diameter is smaller near collision point due to second collision. Therefor, for the same momentum ratio from spray fan formed by impinging jets, we may neglect effect of interaction on mass distribution, droplet velocities and diameter.

• Journal of the Korean Magnetics Society
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• v.16 no.4
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• pp.221-227
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• 2006

We have synthesized uniform nanometer sized magnetite particles using chemical coprecipitation technique through a sonochemical method with surfactant such as oleic acid. Magnetite phase nanoparticles could be observed from X-ray diffraction. Magnetite nanoparticles is surface phase morphology and biopolymer-microspheres for Application Medical. Magnetite nanoparticles coated biopolymer. Atomic Force Microscope (AFM) was used to image the coated nanoparticles. Magnetic colloid suspensions containing particles with sodium oleate, chitosan and $\beta$-glucan have been prepared. The morphology of the magnetic biopolymer microsphere particles were characterized using optical microscope. Magnetic hysteresis measurement were performed using a superconducting quantum interference device (SQUID) magnetometer at room temperature to investigate the magnetic properties of the biopolymer microspheres and magnetite coated biopolymer including magnetite nanoparticles. Magnetic Resonance (MR) imaging was used to investigate biopolymer coated nanoparticles and biopolymer microspheres.