• 제목/요약/키워드: Plasma exchange

검색결과 116건 처리시간 0.024초

반도체 식각 공정용 냉각 시스템 구축을 위한 AMESim 모델 개발 (A Study on the Development of AMESim Model for Construction of Cooling System for Semiconductor Etching Process)

  • 김대현;김광선
    • 반도체디스플레이기술학회지
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    • 제16권3호
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    • pp.106-110
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    • 2017
  • Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

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식각 공정용 냉각시스템에서의 직접 냉각 방식과 간접 냉각 방식에 관한 연구 (A Study on Direct Cooling and Indirect Cooling in Etching Process Cooling System)

  • 장경민;김광선
    • 반도체디스플레이기술학회지
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    • 제17권3호
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    • pp.100-103
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    • 2018
  • Due to the plasma applied from the outside, which acts as an etchant during the etching process, considerable heat is transferred to the wafer and a separate cooling process is performed to effectively remove the heat after the process. In this case, a direct cooling method using a refrigerant is suitable for cooling through effective heat exchange. The direct cooling method using the refrigerant using the latent heat exchange is superior to the cooling method using the sensible heat exchange. Therefore, in this paper, AMESim is used to design a direct refrigerant cooling system using latent heat exchange simulator was built.The constructed simulator is reliable compared with the actual experimental results. It is expected that this simulator will help to design and search for optimal process conditions.

Cucurbita pepo에서 분리한 Light Membrane Vesicle의 ATPase와 Phosphatase의 정제 및 특성 (Purification and Characterization of ATPase and Phosphatase of Light Membrane Vesicles Isolated from Cucurbita pepo)

  • 오승은
    • Journal of Plant Biology
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    • 제33권4호
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    • pp.325-332
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    • 1990
  • Light membrane vesicles were isolated from the zucchini hypocotyl by floatation on ficoll density gradients and the proteins were solubilized with Triton X100. Three ATP-hydrolyzing enzymes were partially purified by ion-exchange and gel filtration chromatography and isoelectric focusing. There are plasma membrane-type ATPase whose activity was inhibited by vanadate but not by nitrate, tonoplast-type ATPase which was sensitive to nitrate but insensitive to vanadate and one having a phosphatase activity with a pI value different from that of an acid phosphatase. A fraction was obtained after DEAE-ion-exchange chromatography crossreacting with polyclonal antibodies against Ca2+ -ATPase from human erythrocytes.

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혈장 총 율기 포집 능력(TRAP) 수준 및 항산화 비타민 영양상태와 인체 임파구 DNA 손상정도와의 상호관련성 연구 (The Associations between Plasma Concentrations of Total Radical-Trapping Antioxidant Potential(TRAP), Antioxidant Vitamins and DNA Damage in Human Lymphocytes)

  • 강명희
    • Journal of Nutrition and Health
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    • 제34권4호
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    • pp.401-408
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    • 2001
  • The spontaneous frequency of genetic damage and the possible relationship of this damage to total radical-trapping antioxidant potential(TRAP) and antioxidant vitamins, including plasma levels of $\alpha$-carotene, $\beta$-carotene, cryptoxanthin, retinol, $\alpha$-tocopherol and ${\gamma}$-tocopherol in humans were investigated in 57 subjects using two indices of genetic damage, SCE & HFC frequency. The mean of SCE and HFC frequencies were weakly correlated with plasma TRAP(r=-0.305, p<0.1 for SCEs: r=-0.297, p<0.1 for HFCs, respectively), but those were strongly negatively correlated with plasma $\beta$-carotence(r=-0.385, p<0.01 for SCEs : r=-0.392, p<0.01 for HFCs) and cryptoxanthin(r=-0.312, p<0.05 for SCEs : r=0.335, p<0.05 for HFCs, respectively) levels in the subjects. However, those DNA damage markers including SCE and HFC did not correlate with either plasma $\alpha$-carotene, $\alpha$-tocopherol or retinol concentrations. The mean of SCE and HFC frequencies were positively correlated with plasma ${\gamma}$-tocopherol level(r=0.421, p<0.01 for SCEs : r=0.399, p<0.01 for HFCs, respectively). These findings indicate that increased cytogenetic DNA changes, as determined by SCE and HFC frequencies are possibly associated with generation of free radicals in lymphocytes and decreased plasma antioxidant vitamin($\beta$-carotene and cryptoxanthin) status in the subjects. (Korean J Nutrition 34(4) : 401~08, 2001)

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몬테카를로 계산 방식에 의한 RF 플라즈마 에칭 시스템에서의 이온 분포 계산 (Calculation of ion distribution in an RF plasma etching system using monte carlo methods)

  • 반용찬;이제희;윤상호;권오섭;김윤태;원태영
    • 전자공학회논문지D
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    • 제35D권5호
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    • pp.54-62
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    • 1998
  • In a plasma etching system, ions become an important parameter in determining the wafer topography which depends on both the physical sputtering mechanism and the chemically enhanced reaction. this paper reports the energy and angular distributions of ions across the plasma sheath using a monte carlo method. The ion distribution is mainly affected by the magnitude of the sheath voltage and by the collision in the sheath. Furthemore, the local potential distribution in a plamsa sheath has been determined by solving the poisson's equation. In th is work, ionic collisions were cosidered in terms of both charge exchange and momentum transfer. The three-dimensional distributions of ions were calculated with varying the input process conditions in the plasma reactor.

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Separation of Goid, Palladium and Platinum in Chromite by Anion Exchange Chromatography for Inductively Coupled Plasma Atomic Emission Spectrometric Analysis

  • 최광순;이창현;박영재;조기수;김원호
    • Bulletin of the Korean Chemical Society
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    • 제22권8호
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    • pp.801-806
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    • 2001
  • A study has been carried out on the separation of gold, iridium, palladium, rhodium, ruthenium and platinum in chromite samples and their quantitative determination using inductively coupled plasma atomic emission spectrometry (ICP-AES). The dissolution condition of the minerals by fusion with sodium peroxide was optimized and chromatographic elution behaviour of the rare metals was investigated by anion exchange chromatography. Spectral interference of chromium, a matrix of the minerals, was investigated on determination of gold. Chromium interfered on determination of gold at the concentration of 500 mg/L and higher. Gold plus trace amounts of iridium, palladium, rhodium and ruthenium, which must be preconcentrated before ICP-AES was separated by anion exchange chromatography after reducing Cr(Ⅵ) to Cr(III) by H2O2. AuCl4- retained on the resin column was selectively eluted with acetone- HNO3-H2O as an eluent. In addition, iridium, palladium, rhodium and ruthenium remaining on the resin column were eluted as a group with concentrated HCl. However, platinum was eluted with concentrated HNO3. The recovery yield of gold with acetone-HNO3-H2O was 100.7 ${\pm}2.0%$, and the yields of palladium and platinum with concentrated HCl and HNO3 were 96.1 ${\pm}1.8%$ and 96.6 ${\pm}1.3%$, respectively. The contents of gold and platinum in a Mongolian chromite sample were 32.6 ${\pm}$ 2.2 ${\mu}g$/g and 1.6 $\pm$ 0.14 ${\mu}g$/g, respectively. Palladium was not detected.

Monte Carlo Simulation for Particle Behavior of Recycling Neutrals in a Tokamak Diverter Region

  • Kim, Deok-Kyu;Hong, Sang-Hee;Kihak Im
    • Nuclear Engineering and Technology
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    • 제29권6호
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    • pp.459-467
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    • 1997
  • The steady-state behavior of recycling neutral atoms in a tokamak edge region has been analyzed through a two-dimensional Monte Carlo simulation. A particle tracking algorithm used in earlier research on the neutral particle transport is applied to this Monte Carlo simulation in order to perform more accurate calculations with the EDGETRAN code which was previously developed for a two-dimensional edge plasma transport in the authors' laboratory. The physical model of neutral recycling includes charge-exchange and ionization interactions between plasmas and neutral atoms. The reflection processes of incident particles on the device wall are described by empirical formulas. Calculations for density, energy, and velocity distributions of neutral deuterium-tritium atoms have been carried out for a medium-sized tokamak with a double-null configuration based on the KT-2 conceptual design. The input plasma parameters such as plasma density, ion and electron temperatures, and ion fluid velocity are provided from the EDGETRAN calculations. As a result of the present numerical analysis, it is noticed that a significant drop of the neutral atom density appears in the region of high plasma density and that the similar distribution of neutral energy to that of plasma ions is present as frequently reported in other studies. Relations between edge plasma conditions and the neutral recycling behavior are discussed from the numerical results obtained herein.

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타우린 복용이 정상 성인여성의 혈장 총지방산 및 인지질 지방산패턴에 미치는 영향 (Effects of Oral Taurine Supplementation on Plasma Total and Phospholipid Fatty Acid Patterns in Healthy Female Adults)

  • 박태선
    • Journal of Nutrition and Health
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    • 제31권8호
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    • pp.1315-1323
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    • 1998
  • Effect of oral taurine supplementation on plasma total and phospholidpid -fatty acid profiles and their metabolism were evaluated in healthy female adults. Among twenty five female volunteers(23.6$\pm$0.3 years old ) participated in the taruine supplementation program(6g taurine /day), twenty four subjects succesfully completed the 2 week program , and only nine subjects continued to take taurine for another 2 weeks. Levels of plasma fatty acids and taruine were measured by gas-liquid chromatobraphy and an automated amino acid analyzer based on ion exchange chromatography, respectively. Plasma taurine concentration s of the subjects were 108. 7$\pm$3.4 , 184.2$\pm$8.2 and 235.9$\pm$77.0$\mu$emol/L at 0 , 2 and 4 weeks of taurine supplementation. Fatty acid compositions and elongation and desaturation indices of polyunsaturated fatty acids (PUFA) in plasma total lipids were not influenced by oral taurine supplementation. However, fatty acid compositions and their metabolism in plasma phospholipids were significantly affected by taurine supplementation in female adults. Compared to the values for 0 week, the percentage of saturated fatty acids (SFA) in plasma phospholipid was significantly lowered at 2 weeks, but elevated at 4 weeks of taurine supplementation. In contrast , the percentage of phospholipid PUFA significantly increased at 2 weeks and decreased at 4 weeks of taurine supplementation from to the values for 0 weeks. Foru weeks of oral taurine supplementation signifinatly elevated the eongation index(20 : 4$\omega$6 ⇒22 : 4 $\omega$6, p<0.01), and decreased the desaturation index (20 : 3 $\omega$6 ⇒20 : 4 $\omega$6 , p<0.01) of $\omega$6 fatty acids in plasma phospholipids. Plasma taurine concentration was positively correlated with the percentage of 14 : 0 fatty acids and the enlongation index o f$\omega$3 fatty acids(20 : 5 $\omega$3 ⇒22 : 5 $\omega$3), and thenegatively correlated with the percentage of 20 : 0 in plasma phospholipids. These results indicate that oral taurine supplementation for 4 weeks signidicantly elelvated the percentage of SFA, and lowered the percentage of PUFA in plasma phospholipids with no influence on plasm total fatty aicd composition in healthy female adults.

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Exchange Transfusion Treatment for Dapsone-induced Methemoglobinemia

  • ;이장영
    • 대한임상독성학회지
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    • 제6권1호
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    • pp.37-41
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    • 2008
  • Methemoglobinemia can be caused by dapsone toxicity. We report a case dapsone induced methemoglobinemia unresponsive to methylene blue successfully treated by exchange transfusion. A 52-year-old male ingested a handful of dapsone. He presented with severe peripheral cyanosis in lips and fingertips and his methemoglobin level was found to be 21.9%. After admission, methylene blue (1%) at 1 mg/kg was injected each time peripheral cyanosis and rising serum methemoglobin occurred. Despite methylene blue therapy, the patient‘s methemoglobin level continued to fluctuate. Five days after the injections of methylene blue, many Heinz bodies were visualized in the peripheral blood, suggestive of hemolytic anemia occurrence. By hospital day 6, serum methemoglobine levels were elevated and not measurable (> 50%) and the patient was constantly in a semi-comatose mental state. An exchange transfusion carried out by utilizing 6 units of packed red blood cells and 4 units of fresh frozen plasma was performed. The patient's methemoglobin levels were subsequently kept up below 20% and his peripheral cyanosis receded. Physicians should recognize the important role of exchange transfusion in refractory dapsoneinduced methemoglobinemia.

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식이내의 타우린 또는 글라이신 보강이 흰쥐의 혈장과 간의 유리아미노산 농도 및 패턴에 미치는 영향 (Effect of Dietary Taurine or Glycine Supplementation on Plasma and Liver Free Amino Acid Concentrations in Rats)

  • 박정은
    • Journal of Nutrition and Health
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    • 제31권2호
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    • pp.126-134
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    • 1998
  • Our previous study demonstrated that dietary taurine or glycine supplementation significantly lowered plasma and hepatic cholesterol and triglyceride concentrations in rats fed a cholesterol-free diet. In the present study, the effect of long term dietary taurine or glycine supplementation, for the purpose of preventing and/or treating of hyperlipidemia and other known biological functions, on plasma and hepatic free amino acid concentrations and profiles were evaluated in rats. Three groups of male rats(110-130g) were fed a control diet(CD), taurine-supplemented diets(TSD ; CD+ 1.5% taurine) or glycine-supplemented diet(GSD ; CD+1.5% glycine) for 5 weeks. Plasma and hepatic free amino acid concentrations were determined by an automated amino acid analyzer based on ion-exchange chormatography. The feeding of TSD for 5 weeks yielded a 444% higher plasma taurine concentration , and the feeding GSD for the same period resulted in a 143% higher plasma glycine level in rats compared to those fed DB. Hepatic taurine concentration was significantly higher in rats fed TSD(145% increase) compared to the control rats. However, hepatic glycine concentration was not influenced by dietary glycine supplementation , which implies that the massive dose of glycine entering the body was more rapidly metabolized or excreted than taurein. Dietary taurine or glycine supplementation resulted in similar changes in plasma free amino acid concentrations, except in levels of taurine and glycine. Plasma levels of histidine, lysine, phenylalanine , alanine, proline, hydroxypoline, $\alpha$-aminogutyric acid, cystathionine and ethanolamine were significantly higher in rats fed TSD or GSD than those fed GD. Glycine supplementation did not change hepatic free amino acid concentrations as compared to CD. Concentrations of most hepatic free amino acids were not influenced by dietary taurine supplementation with the exception of significantly higher levels of asparate and tyrosine(56-63% increase) and lower levels of histidine and glutamate(33-34% decrease) compared to the control rats. These results suggest long-term dietary taurine or glycine supplementation resulted in increases in most plasma free amino acid levels, but did not cause a characteristic change in plasma aminogram pattern compared to rats fed CD.

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