• Title/Summary/Keyword: oxygen effect

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Studies on the Effect of 'Gal Geun Tang' upon Stress Resistance of Rats (갈근탕(葛根湯) 투여가 흰 쥐의 스트레스 저항 반응에 미치는 영향에 관한 연구)

  • Kwon, Chang-Ho
    • Korean Journal of Pharmacognosy
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    • v.5 no.4
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    • pp.217-222
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    • 1974
  • Oxygen consumption rate has been determined to study the effect of 'Gal Geun Tang' upon stress resistance of rats. The oxygen consumption rate of liver tissue increased slightly when normal rats were given the Gal Geun Tang infusion only. When rats were given the infusion after an injection of typhoid vaccine, the elevated boby temperature and oxygen consumption rate due to typhoid vaccine fell to normal level. From this result, it is concluded that 'Gal Geun Tang' has a function that may normalize abnormally strained liver metabolism. Oxygen consumption rate of the rats significantly increased when rats were exposed to cold condition. However, under the same condition it rather maintained the normal consumption rate when the rats were given previously "Gal Geun Tang". It is suggested that 'Gal Geun Tang' has an effects that impairs the immune response from cold stress. The rats that were given Cinnamomi Ramulus('Ge Ji Tang') showed less effect than the group of 'Gal Geun Tang'.

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The Effect of Glucose Deprivation on the Oxygen Deprivation-induced Changes of [[$^3H$]-5-hydroxytryptamine Release in Rat Hippocampal Slices (흰쥐 해마 절편에서 산소고갈에 의한 [$^3H$-5-hydroxytryptamine 유리변동에 미치는 포도당고갈의 영향)

  • 이경은
    • Toxicological Research
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    • v.14 no.4
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    • pp.483-488
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    • 1998
  • During cerebral ischemia two important factors such as hypoxia and reduction of glucose can act as modulating stressor affecting the release of amine neurotransmitters including 5-hydroxytryptamine (5-HT). This study was performed to investigate the effect of glucose deprivation on the oxygen deprivation-induced changes of [3H]-5-HT release in the rat hippocampal slices. Experimental groups were divided into 4 groups for this study: normoxic/normoglycemic group, oxygen-deprived group, glucose-deprived group, and oxygen/glucose-deprived group. The hippocampus of rat brain was sliced by 400 $\mu\textrm{m}$ thickness with manual chopper. After 30 minutes preincubation in the normal buffer, the slices were incubated for 20 min in buffer containing [3H]-5-HT (0.1 M, 74 $\mu\textrm$Ci) for uptake. To measure the release of [3H]-5-HT into the buffer, the incubation medium was drained of and refilled with fresh buffer every ten minutes through a sequence of 14 tubes. Oxygen deprivation by gassing with 95% $N_2$/5% $CO_2$ and/or glucose deprivation was done in the 6th and 7th tube. The radioactivities in each buffer and the tissue were counted using scintillation counter. The results were expressed as fractional release. When slices were exposed to oxygen-deprived media for 20 min, the diminution followed by the rebound release of [3H]-5-HT was observed during the post-oxygen deprived period. However, glucose deprivation or oxygen/glucose deprivation markedly increased the release of [3H]-5-HT. which was opposite to the pattern observed in oxygen-deprived group. These results suggested that oxygen deprivation itself inhibits [3H]-5-HT release in rat hippocampal slices during oxygen-deprived period, but additional glucose deprivation convert the inhibitory response to increase of [3H]-5-HT release.

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The Effect of Oxygen in Fuel on the Exhaust Gas Emissions in Diesel Engine (디젤기관에서 연료중의 산소성분이 배기가스 배출특성에 미치는 영향)

  • 유경현;오영택
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.4
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    • pp.59-67
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    • 2000
  • Recently the world is faced with the very serious problems related to the increasing use of the conventional petroleum fuels. THe air pollutions in big cities were also occurred by the exhaust emissions from automobiles. many researchers have been attracted various oxygenated fuels as an alternative fuel and a renewable fuel for the measure of these problems. In this study the effect of oxygen in fuel on the exhaust gas emissions has been investigated with oxygenated fuels as an alternative fuel for diesel engine. The exhaust gas emission were investigated by comparing with that of the diesel fuel. The vegetable fuel oil such as soybean oil gives lower smoke level than that with diesel fuel. Furthermore the smoke emission is more affected by the oxygen content in fuel than by the fuel viscosity. This study concluded that the fuels including oxygen might be a good measure to reduce smoke in diesel engine because the oxygen strongly influenced the combustion process.

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THE KINETIC STUDIES OF GLUCONIC ACID FERMENTATION (PART 1) Effect of Phenol and Catechol Derivatives on Oxygen Transfer in the Fermentation (Gluconic acid의 발효에 관한 연구(제1보) 발효조중 산소이동에 미치는 Phenol 유도분 및 Catechol 유도분의 영향)

  • LEE Keun-Tai;LEE Kyung-Hee
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.11 no.4
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    • pp.205-211
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    • 1978
  • The effect of phenol derivatives (guaiacol, vanillin, o-vanillin, eugenol) and catechol derivatives (pyrogallol, resoicinol) to enhance the volumetric oxygen transfer coefficient, in the aerobic fermentation was studies. Guaiacol, vanillin, o-vanillin, pyrogallol and resorcinol revealed to enchance the volumetric oxygen transfer coefficient, and eugenol had no such ability. The enhancement of the oxygen transfer ability is probably due to the formation of the charge transfer complex by the derivatives and oxygen molecules.

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The effect of oxygen doping on organic light emitting diodes by oxygen plasma treatment

  • Hong, Ki-Hyon;Kim, Ki-Soo;Kim, Sung-Jun;Lee, Jong-Lam;Choi, Ho-Won;Tak, Yoon-Heung
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.485-487
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    • 2008
  • By the oxygen plasma exposure to the organic light-emitting diodes, the turn-on voltage decreased from 10.5 to 7 V and luminance increased from 470 to $852\;cd/m^2$. Synchrotron radiation photoelectron spectroscopy results showed that during oxygen plasma exposure, oxygen ions were diffused into organic layer and induced p-type doping effect.

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Effect of substrates on the geometries of as-grown carbon coils

  • Park, Semi;Kim, Sung-Hoon;Kim, Saehyun;Jo, Insu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.11a
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    • pp.163-164
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    • 2012
  • Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. The substrate with oxygen incorporation and the substrate without oxygen incorporation were employed to elucidate the effect of substrate on the formation of carbon coils. The characteristics (formation densities, morphologies, and geometries) of the deposited carbon coils on the substrate were investigated. In case of Si substrate, the microsized carbon coils were dominant on the substrate surface. While, in case of oxygen incorporated substrate, the nanosized carbon coils were prevail on the substrate surface. The cause for the different geometry formation of carbon coils according to the different substrates was discussed in association with the different thermal expansion coefficient values between the substrate with oxygen incorporation and the substrate without oxygen incorporation.

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Effect of Oxygen in the Synthesis of ZnO Nanowires (ZnO 나노선의 합성에서의 미량산소의 영향)

  • Park, Kyung-Su;Choi, Young-Jin;Park, Jae-Gwan;Kang, Gyo-Sung;Lim, Dong-Gun;Park, Jae-Hwan
    • Korean Journal of Materials Research
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    • v.17 no.9
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    • pp.458-462
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    • 2007
  • The effect of oxygen in the synthesis of oxide nanowires by using carbothermal reduction process have been studied thermodynamically and kinetically. By using laboratory air, ZnO nanowires could be fabricated in the carbothermal reduction process and a metal oxidation process. As the processing pressure decreases, the diameter of the nanowires decreases and the oxygen vacancy increases. As the processing pressure increases, the oxygen vacancy decreases and the shape of the ZnO becomes plate-like.

Effect of Mixed Jet with Primary Nozzle Area Ratio of Ejector on Oxygen Transfer Characteristics (산소 전달 특성에 미치는 이젝터 구동 노즐 면적비에 따른 혼합 분류의 영향)

  • Park, Sang Kyoo;Yang, Hei Cheon
    • Journal of ILASS-Korea
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    • v.27 no.3
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    • pp.126-133
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    • 2022
  • The objective of this is to experimentally investigate the effect of mixed jet on the oxygen transfer characteristics with the primary nozzle area ratio of an annular nozzle ejector for the application of a microbial fuel cell. A direct visualization method with a high speed camera system was used to capture the horizontal mixed jet images, and a binarization technique was used to analyze the images. The clean water unsteady state technique was used for the oxygen transfer measurement. The air-water mixed jet discharging into a water tank behaved similar to a buoyancy or horizontal jet with the primary nozzle area ratio. It was found that an optimum primary nozzle area ratio was observed where the oxygen transfer performance reached its maximum value due to the decrease of air volume fraction and the increase of jet length and air bubble dispersion.

A Study About the Effect of EGR Ratio on DME HCCI Combustion Process (EGR 율이 DME HCCI 엔진연소과정에 미치는 영향에 관한 연구)

  • Lim, Ocktaeck
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.37 no.10
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    • pp.879-886
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    • 2013
  • This study aims to provide helpful suggestions for understanding the effect of high EGR on DME HCCI combustion. This study determined which between oxygen partial pressure and oxygen concentration was the main factor affecting the LTHR heating ratio. Furthermore, EGR and the supercharging effect were investigated. To define the parameters for the EGR ratio and supercharging pressure, a numerical analysis of the chemical reaction was conducted under the following conditions: (1) variation of EGR ratio, oxygen concentration, and oxygen content; (2) variation of oxygen partial pressure while the oxygen concentration was almost constant; and (3) variation of oxygen concentration while oxygen partial pressure was constant with EGR and supercharging. The results show that an increase in EGR reduces the combustion duration. On the other hand, an increase in boost pressure increases the combustion duration. Finally, the EGR and boost pressure affect the amount of increase in LTHR.

PD184352 Releases the Regular Hypoxic Reversible DNA Replication Arrest in T24 Cells

  • Martin, Leenus
    • BMB Reports
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    • v.40 no.6
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    • pp.895-898
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    • 2007
  • The oxygen dependent regulation of DNA replication is an essential property of proliferating mammalian cells. In human T24 bladder cancer cells, several hours of hypoxia leads to reversible DNA replication arrest and re-entry of oxygen induces a burst of replication initiation. This short communication provides strong evidence that PD184352 initiates DNA replication in living hypoxic cells without elevating the oxygen level. PD184352 releases the regular hypoxic replicon arrest, however, at a low intensity compared to the effect of reoxygenation. Moreover, PD184352 shows no effect on normoxically incubated as well as reoxygenated T24 cells.