• Title/Summary/Keyword: High pressure processing

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Effects of Particle Size and High Pressure Process on the Extraction Yield of Oil Compounds from Soybean Powder Using Hexane and Supercritical Fluid (입자 크기와 초고압 처리에 따른 유기용매와 초임계 유체 추출법에서의 대두유 추출수율의 변화)

  • Yoon, Won-Byong
    • Food Engineering Progress
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    • v.15 no.3
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    • pp.203-208
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    • 2011
  • Effects of particle size and high pressure processing on the extraction rate of oil compounds from soybean powder were evaluated by Soxhlet method using hexane and supercritical fluid extraction (SFE) using $CO_{2}$. SFE was carried out at 4,000 psi and $50^{\circ}C$ for 4 hr. The mean particle sizes were varied from 26.7 to 862.0 ${\mu}m$ by controlling milling time. Saturation solubility increased as the particle size decreased. At large particle size, high pressure processing (HPP) showed higher extraction yield in both hexane extraction and SFE, but, as the particle size decreased, the HPP was irrelevant to the extraction yield in SFE. The higher extraction rate obtained from the smaller particle size. The scanning electronic microscopy of soybean powder treated by HPP showed pores on the surface of the particle. The higher extraction rate and yield from HPP treatment might be due to the less internal resistance of transferring the solvent and miscellar in the solid matrix by collapsing of tissues.

Nanocrystallization of Metallic Powders during High Pressure Torsion Processing (금속분말의 고압비틀림 성형시 나노결정화)

  • Yoon, Seung-Chae;Kim, Hyoung-Seop
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.105-106
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    • 2007
  • Microstructure and hardness of metallic powder of Cu was studied after high pressure torsion (HPT) with 10 torsions and high pressure of 6 GPa. The size Cu grain decreases drastically after HPT and reaches the nano size range. During HPT, Cu powder increases hardness and Hall-Petch hardening, due to the decreasing grain size. In this study, effect of HPT on the hardness of Cu powders and consolidation with Nanocrystalline of the work reported here. The results indicated that Cu powder has a beneficial effect on homogeneous deformation, reducing grain size.

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Analyses of Sever Plastic Deformation Behavior of Hot Isostatic Pressed Ni-base Superalloy during High Pressure Torsion Process (열간정수압성형공정으로 제조된 니켈기 초내열합금의 고압비틀림 공정을 통한 강소성 변형거동 분석)

  • Lee, D.J.;Lee, Y.;Kim, H.-K.;Kwon, Y.-N.;Kim, H.S.;Yoon, E.Y.
    • Transactions of Materials Processing
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    • v.25 no.4
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    • pp.254-260
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    • 2016
  • In this study, hot isostatic pressed Ni-base superalloy was subjected by high-pressure torsion process to improve the dispersion of gamma prime phase, mechanical properties and remove prior particle boundaries. The resulting microstructural size decreases and prior particle boundaries removed with increasing strain by high-pressure torsion process. Moreover, the microhardness values and room temperature tensile strength were enhanced. However, the tensile elongation was decreased as increasing strain due to fast crack propagation along the refined and well dispersed gamma prime particles.

Influence of Frictional Behavior Depending on Contact Pressure on Springback at U Draw Bending (접촉 압력에 의한 마찰 특성 변화가 U 드로우 굽힘에서의 스프링백에 미치는 영향)

  • Han, S.S.
    • Transactions of Materials Processing
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    • v.20 no.5
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    • pp.344-349
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    • 2011
  • Variation of contact pressure causes change of friction coefficient, which in turn changes stress distribution in the sheet being formed and final springback. In the present study, U-draw bending experiments were carried out under constant blank holding force(BHF) and different blank sizes, and finite element analysis was conducted with and without considering contact pressure effect on friction. When the BHF was sufficiently high, the degree of springback was different between constant blank holding pressure condition and that with varying blank holding pressure. Finite element analysis considering the influence of contact pressure effect on friction could explain the occurrence of springback.

The Characteristics on Arc Pressure Distribution of TIG Welding with Shield Gas Mixing Ratio (TIG 용접에서의 실드 가스 혼합비에 따른 아크 압력분포 특성)

  • Oh Dong-Soo;Kim Yeong-Sik;Cho Sang-Myung
    • Journal of Welding and Joining
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    • v.23 no.1
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    • pp.41-47
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    • 2005
  • Arc pressure is one of important factors in understanding physical arc phenomena. Especially it affects on the penetration, size and shape of TIG welding. Some researches were reported on the effect of arc pressure in low and middle current region. But there are not any research in high current region. The purpose of this study is to investigate the arc pressure distribution with mixing ratio of shield gas such as Ar and He gases. A Cu block with water cooling was specifically designed and used as an anode electrode in order to measure the arc pressure in high current region. Then, the arc pressure distribution was measured with change in welding current and mixing ratio of shield gases. The arc force was obtained by numerically integrating the measured results. As the results, it was shown that the arc pressure was concentrated at the central part of the arc in middle and high current regions when a pure Ar gas was used. In case of Ar + He mixing gas, the arc pressure was much lower than that of pure Ar gas. In addition, it was widely distributed to radial direction.

Applications of Plasma Modeling for Semiconductor Industry

  • Efremov, Alexandre
    • Electrical & Electronic Materials
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    • v.15 no.9
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    • pp.10-14
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    • 2002
  • Plasma processing plays a significant role in semiconductor devices technology. Development of new plasma systems, such as high-density plasma reactors, required development of plasma theory to understand a whole process mechanism and to be able to explain and to predict processing results. A most important task in this way is to establish interconnections between input process parameters (working gas, pressure flow rate input power density) and a various plasma subsystems (electron gas, volume and heterogeneous gas chemistry, transport), which are closely connected one with other. It will allow select optimal ways for processes optimizations.

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Effect of Salt Contents on High Pressure Inactivation of Microorganism in Doenjang (염 함량이 된장의 초고압 살균에 미치는 영향)

  • Mok, Chulkyoon
    • Food Engineering Progress
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    • v.15 no.4
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    • pp.318-323
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    • 2011
  • High pressure processing (HPP) technology was applied to inactivate the microorganisms in Doenjang (soybean paste) and the effects of salt concentration on the HPP inactivation of microorganisms were analyzed. The microorganisms in Doenjang containing low salt content showed greater sensitivity to HPP than those with high salt content. HPP inactivation effects decreased as salt concentration of Doenjang increased. The HPP sensitivity decreased in the order of fungi, yeasts, bacteria in terms of microorganism type. The HPP of Doenjang at 6,500 atm for 40 min inactivated most yeasts and fungi, indicating that the HPP technology was applicable to control the microorganisms in Doenjang, especially with a low level of salt.

A Study on Injection and Combustion of D.I. Diesel Engine with Electronic-hydraulic Fuel Injection System (전자유압식 분사계를 갖는 D.I. 디젤기관의 분사 및 연소에 관한 연구)

  • Kim, Hyun-Gu;Ra, Jin-Hong;Ahn, Soo-Kil
    • Journal of Fisheries and Marine Sciences Education
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    • v.9 no.1
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    • pp.83-97
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    • 1997
  • Diesel engine is widely used for ship and industry source of power because of its high thermal efficiency and reliability and durability. However it lead to air pollution due to exhaust gas, and it is important to develop diesel engine of lower air-pollution to decrease the hazardous exhaust gas emissions. As one of the ways, the study for practically using the high pressure of fuel injection and variable injection timing system is being processing. The high pressure injection, which is said to be an effective means for reducing both NOx and particulate emissions, and great improvements in combustion characteristics have been reported by many researchers. In this study, electronic-hydraulic fuel injection system and hydraulic fuel injector system have been applied to the D.I. test engine for high pressure injection and variable injection timing. The injection pressure and injection rate depending upon accumulator pressure were measured with strain gage and Bosch injection rate measuring system before fitting the system into test engine, and analyzed the characteristics of the injection system. The combustion characteristics with this injection system has been analyzed with data concerning heat release rate, pressure rising rate, ignition point, ignition delay and maximum pressure value.

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Enhancement of Anticancer Activities of Ephedra sinica, Angelica gigas by Ultra High Pressure Extraction (초고압 추출 처리에 의한 마황과 당귀의 항암 활성 증진)

  • Jeong, Hyang-Suk;Han, Jae-Gun;Ha, Ji-Hye;Kim, Young;Oh, Sung-Ho;Kim, Seoung-Seop;Jeong, Myoung-Hoon;Choi, Geun-Pyo;Park, Uk-Yeon;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.17 no.2
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    • pp.102-108
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    • 2009
  • This study was performed to enhance anticancer activities of E. sinica, and A. gigas by ultra high pressure extraction process. The cytotoxicity of E. sinica and A. gigas on human kidney cell (HEK293) was as low as 24.94% and 25.3% in adding 1.0 $mg/m{\ell}$ of the sample extracted at 500 Mpa for 15 minute. Generally, the inhibition of cancer cell growth on A549 and MCF-7 was increased over 20% in the ultra high pressure samples, compared to the conventional extraction process. Under the extracts from ultra high pressure process showed not only the strongest anticancer activities, but also had better stability than normal extracts. It was also found that the extracts of A. gigas reduced the hypertrophy of the internal organs, such as adrenal and spleen caused stresses in several mouse models.

Toxicity Reduction and Improvement of Anticancer Activities from Rhodiola sachalinensis A. Bor by Ultra High Pressure Extracts Process (초고압 공정에 의한 홍경천의 독성 감소 및 항암활성 증진)

  • Kim, Cheol-Hee;Kwon, Min-Chul;Qadir, Syed Abdul;Hwang, Baik;Nam, Jong-Hyeon;Lee, Hyeon-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.6
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    • pp.411-416
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    • 2007
  • This study was performed to investigate the reduction of toxicity and improvement of anticancer activities from R. sachalinensis by ultra high pressure extracts process. The cytotoxicity on human kidney cell (HEK293) and human lung cell (HEL299) was showed below 20.4% and 21.6% as compare to normal extracts in adding 1.0 $mg/m{\ell}$ concentration. This showed that toxic materials through ultra high pressure processing is broken or degraded. Because bond such as hydrogen bond, electrostatic bond, Van der waals bond, the hydrophobic bond, can be broken by high pressure. The anticancer activity was also increased in over 7% by high pressure processing in A549, AGS, MCF-7 and Hep3B cells. The result showed that extraction by high pressure have low cytotoxicity and high anticancer activity. So, the high pressure extraction technology can play an important role in eruption of new material with high biological activity.