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FTS법을 이용한 ITO박막의 제작 (Preparation of ITO thin films by FTS(Facing Targets Sputtering) method)

  • 김건희;금민종;김한기;손인환;장경욱;이원재;김경환
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
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    • pp.203-206
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    • 2004
  • In this study the ITO thin films were prepared by using FTS(Facing Targets Sputtering) system. The electric characteristics, transmittance, surface roughness of ITO thin films were investigated as a function of varying input current and working gas pressure at room temperature. As a result, the ITO thin film was fabricated with resistivity $6{\times}10^{-4}[\Omega{\cdot}cm]$, carrier mobility $52.11[cm^2/V{\cdot}sec]$, carrier concentration $1.72{\times}10^{20}[cm^{-3}]$ of ITO thin film at working pressure 1mTorr and input current 0.6A.

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Penicillium verruculosum의 원형질체 형성과 재생 (Formation and Regeneration of Penicillium verruculosum Protoplasts)

  • Chung, Ki-Chul;Park, Chang-Ryeol
    • 한국미생물·생명공학회지
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    • 제16권2호
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    • pp.156-162
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    • 1988
  • 섬유소 분해효소를 생산하는 P. verruculosum F-3 의 세포융합에 관한 연구의 일환으로 균사체로부터의 원형질체 형성과 재생 최적조건을 검토하였다. 세포벽 분해효소로 유효한 각종시판효소제제중 0.5%(w/v) Novozym 234가 가장 효과적이었고 PDY 배지로 3$0^{\circ}C$ 20시간 배양한 균사체 400mg을 3$0^{\circ}C$ 1시간 반응시 가장 많은 원형질체가 형성되었다. 원형질체 형성을 위한 최적 삼투압 조절제는 0.7M sorbitol(pH5.6)이었고 원형질체 재생을 위한 최적 삼투압 조절제는 0.6M MgSO$_4$(pH 5.6)이었으며 RCM에서의 재생율은 4.6~27.8%였다. 원형질체를 RLM에 배양시 균사체로 환원되는 형태적 변화가 관찰되었다.

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Effects of Intraperitoneally Administered Lipoic Acid, Vitamin E, and Linalool on the Level of Total Lipid and Fatty Acids in Guinea Pig Brain with Oxidative Stress Induced by H2O2

  • Celik, Sait;Ozkaya, Ahmet
    • BMB Reports
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    • 제35권6호
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    • pp.547-552
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    • 2002
  • The aim of our study was to investigate the protective effects of intraperitoneally-administrated vitamin E, dl-alpha lipoic acid, and linalool on the level of total lipid and fatty acid in guinea pig brains with oxidative stress that was induced by $H_2O_2$. The total brain lipid content in the $H_2O_2$ group decreased when compared to the $H_2O_2$ + vitamin E (p<0.05), $H_2O_2$ + linalool (p<0.05), ALA (p<0.05), control (p<0.01), linalool (p<0.01), and vitamin E (p<0.01) groups. While the proportion of total saturated fatty acid (${\Sigma}SFA$) in the $H_2O_2$ group significantly increased (p<0.005) when compared to the vitamin E group, it only slightly increased (p<0.01) when compared to the control and $H_2O_2$ + vitamin E groups. The ratio of the total unsaturated fatty acid (${\Sigma}USFA$) in the $H_2O_2$ groups was lower (p<0.05) than the control, vitamin E, and $H_2O_2$ + vitamin E groups. The level of the total polyunsaturated fatty acid (${\Sigma}PUEA$) in the $H_2O_2$ group decreased in when compared to the control, vitamin E, and $H_2O_2$ + vitamin E groups. While the proportion of the total w3 (omega 3), w6 (omega 6), and PUFA were found to be lowest in the $H_2O_2$ group, they were slightly increased (p<0.05) in the lipoic acid group when compared to the control and $H_2O_2$ + lipoic acid groups. However, the level of ${\Sigma}SFA$ in the $H_2O_2$ group was highest; the level of ${\Sigma}USFA$ in same group was lowest. As the proportion of ${\Sigma}USFA$ and ${\Sigma}PUFA$ were found to be highest in the linalool group, they were decreased in the $H_2O_2$ group when compared to the control group. Our results show that linalool has antioxidant properties, much the same as vitamin E and lipoic acid, to prevent lipid peroxidation. Additionally, vitamin E, lipoic acid, and linalool could lead to therapeutic approaches for limiting damage from oxidation reaction in unsaturated fatty acids, as well as for complementing existing therapy for the treatment of complications of oxidative damage.

Syntheses and Reactions of Iridium Complexes Containing Mixed Phosphine-Olefin Ligand: (3-(Diphenylphosphino)propyl)(3-butenyl)phenylphosphine

  • Young-ae W. Park;Devon W. Meek
    • Bulletin of the Korean Chemical Society
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    • 제16권6호
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    • pp.524-528
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    • 1995
  • The reaction of [IrCl(cod)]2 with ppol ligand, Ph2PCH2CH2CH2P(Ph)CH2CH2CH=CH2, in ethanol gives an iridium complex, whose structure is converted from an ionic form, [Ir(cod)(ppol)]Cl·2C2H5OH (1),in polar solvents (ethanol, methanol and acetonitrile), to a molecular form, [IrCl(cod)(ppol)], in non-polar solvents (benzene and toluene). The cationic complexes, [Ir(cod)(ppol)]AsF6·1/2C2H5OH and [Ir(cod)(ppol)]PF6·1/2CH3CN, were prepared to compare with the ionic form by 31P NMR spectroscopy. When carbon monoxide is introduced to 1, cod is replaced by CO to give the 5-coordinated complex, [IrCl(CO)(ppol)]. Hydrogenation of 1-octene was not successful in the presence of 1. In order to verify the reason for 1 not behaving as a good catalyst for hydrogenation, electrophilic reactions with HCl, I2 and HBF4·etherate were performed, which yielded the oxidative addition product, [IrHCl2(ppol)], the substitution product, [IrI(cod)(ppol)], and another cationic product, [Ir(cod)(ppol)]BF4, respectively. Thus, the iridium complex is not sufficiently basic to activate hydrogen atoms or the olefin of the ppol ligand.

Production of Hydrolyzed Red Ginseng Residue and Its Application to Lactic Acid Bacteria Cultivation

  • Kim, Dong-Chung;In, Man-Jin
    • Journal of Ginseng Research
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    • 제34권4호
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    • pp.321-326
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    • 2010
  • Enzymatic treatment conditions for red ginseng residue (RGR) were investigated to apply RGR as a microbial medium. Polysaccharide hydrolyase and protease were screened to obtain high solid and carbohydrate yields, and a good degree of carbohydrate hydrolysis. The optimal dosage and reaction time for Viscozyme, the chosen polysaccharide hydrolyase, were found to be 1.0% (w/w) and 3 h, respectively. Of the tested proteases, Flavourzyme, whose optimal dosage was 0.5% (w/w), was selected. Co-treatment with the optimal dosages of Flavourzyme and Viscozyme increased solid yield, carbohydrate yield, and degree of carbohydrate hydrolysis by 76%, 65%, and 1,865%, respectively, over levels in non-treated RGR. The culture characteristics of Leuconostoc mesenteroides strain KACC 91459P grown in enzymatically hydrolyzed red ginseng residue (ERGR) and RGR suspensions were compared. After cultivation for 6 h, the viable cell counts of both cell suspensions rapidly increased to $1.3{\times}10^9$ colony-forming units (CFU)/g. Moreover, while the viable cell population drastically decreased to $2.4{\times}10^6\;CFU/g$ for cells grown in RGR medium, it was maintained in cells fermented in ERGR medium for 24 h.

저압 $C_6H_6/Ar/O_2$ 화염에서 PAHs 생성 특성 및 플러렌$(C_{60},\;C_{70})$ 합성에 대한 연구 (PAHs Formation Characteristics and Fullerenes $(C_{60},\;C_{70})$ Synthesis in a Low-Pressure $C_6H_6/Ar/O_2$ Flame)

  • 이교우;김용우;황정호;정종수;최만수
    • 한국연소학회지
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    • 제7권4호
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    • pp.36-44
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    • 2002
  • Carbon molecules with closed-cage structures are called fullerenes $(C_{60},\;C_{70})$, whose applications include super-conductors, sensors, catalysts, optical and electronic device, polymer composites, and biological and medical materials. The synthesis of fullerenes has been recently studied with low-pressure benzene/argon/oxygen flames. The formation of fullerene is known as molecular weight growth processes of PAHs (polycyclic aromatic hydrocarbon). This study presents results of PAHs and fullerene measurements performed in a low-pressure benzene/argon/oxygen normal co-flow laminar diffusion flame. Through the central tube of the burner, benzene vapors carried by argon are injected. The benzene vapors are made in a temperature-controlled bubbler. The burner is located in a chamber, equipped with a sampling system for direct collection of condensable species from the flame, and exhausted to a vacuum pump. Samples of the condensable are analyzed by HPLC (High Performance Liquid Chromatography) to determine the yields of PAHs and fullerene. Also, we computed mole fraction of fullerene and PAHs in a nearly sooting low pressure premixed, one-dimensional benzene/argon/oxygen flame (equivalence ratio ${\Phi}=2.4$, pressure=5.33kPa). The object of computation was to investigate the formation mechanism of fullerenes and PAHs. The computations were performed with CHEMKIN/PREMIX. As a result of this study, fullerenes were synthesized in a low pressure (20torr) $C_6H_6/Ar/O_2$ flames and the highest concentration of fullerene was detected just above the visible surface of a flame.

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서로 다른 입자크기의 ZrC가 첨가된 W-ZrC 복합체의 미세구조 및 고온강도에 관한 연구 (Microstructure and Elevated Temperature Strength of W-ZrC Composites with Micrometric and Nanosized ZrC Particles)

  • 한윤수;류성수
    • 한국분말재료학회지
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    • 제21권6호
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    • pp.415-421
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    • 2014
  • W-10vol.%ZrC composites reinforced by micrometric and nanosized ZrC particles were prepared by hot-pressing of 25 MPa for 2 h at $1900^{\circ}C$. The effect of ZrC particle size on microstructure and mechanical properties at room temperature and elevated temperatures was investigated by X-ray diffraction analysis, scanning electron microscope and transmission electron microscope observations and the flexural strength test of the W-ZrC composite. Microstructural analysis of the W-ZrC composite revealed that nanosized ZrC particles were homogeneously dispersed in the W matrix inhibiting W grain growth compared to W specimen with micrometric ZrC particle. As a result, its flexural strength was significantly improved. The flexural strength at room temperature for W-ZrC composite using nanosized ZrC particle being 740 MPa increased by around 2 times than that of specimen using micrometric ZrC particle which was 377 MPa. The maximum strength of 935 MPa was tested at $1200^{\circ}C$ on the W composite specimen containing nanosized ZrC particle.

Cartan Subalgebras of a Semi-restricted Lie Algebra

  • Choi, Byung-Mun
    • 충청수학회지
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    • 제6권1호
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    • pp.105-111
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    • 1993
  • In this paper we show that if a semi-restricted Lie algebra L has an one dimensional toral Cartan subalgebra, then L is simple and $L\simeq_-sl(2)$ or $W(1:\underline{1})$. And we study that if L is simple but not simple and H is 2-dimensional, then H is a torus.

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다양한 배양조건에 따른 Rhodobacter sphaeroides KD131의 광발효 수소생산 (Photo-Fermentative Hydrogen Production by Rhodobacter Sphaeroides KD131 under Various Culture Conditions)

  • 손한나;김동훈;이원태;이영하;김미선
    • 한국수소및신에너지학회논문집
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    • 제22권4호
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    • pp.451-457
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    • 2011
  • Purple non-sulfur (PNS) bacterium $Rhodobacter$ $sphaeroides$ KD131 was studied with the aim of achieving maximum hydrogen production using various carbon and nitrogen sources at different pH conditions. Cells grew well and produced hydrogen using $(NH_4){_2}SO_4$ or glutamate as a nitrogen source in combination with a carbon substrate, succinate or malate. During 48h of photo-heterotrophic fermentation under 110$W/m^2$ illumination using a halogen lamp at $30^{\circ}C$, 67% of 30mM succinate added was degraded and the hydrogen yield was estimated as 3.29mol $H^2$/mol-succinate. However, less than 30% of formate was consumed and hydrogen was not produced due to a lack of genes coding for the formate-hydrogen lyase complex of strain KD131. Initial cell concentrations of more than 0.6g dry cell weight/L-culture broth were not favorable for hydrogen evolution by cell aggregation, thus leading to substrate and light unavailability. In a modified Sistrom's medium containing 30mM succinate with a carbon to nitrogen ratio of 12.85 (w/w), glutamate produced 1.40-fold more hydrogen compared to ammonium sulfate during the first 48h. However, ammonium sulfate was 1.78-fold more effective for extended cultivation of 96h. An initial pH range from 6.0 to 9.0 influenced cell growth and hydrogen production, and maintenance of pH 7.5 during photofermentation led to the increased hydrogen yield.

Validity of self-reported height and weight in elderly Poles

  • Niedzwiedzka, Ewa;Dlugosz, Anna;Wadolowska, Lidia
    • Nutrition Research and Practice
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    • 제9권3호
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    • pp.319-327
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    • 2015
  • BACKGROUND/OBJECTIVES: In nutritional epidemiology, collecting self-reported respondent height and weight is a simpler procedure of data collection than taking measurements. The aim of this study was to compare self-reported and measured height and weight and to evaluate the possibility of using self-reported estimates in the assessment of nutritional status of elderly Poles aged 65 + years. SUBJECTS/METHODS: The research was carried out in elderly Poles aged 65 + years. Respondents were chosen using a quota sampling. The total sample numbered 394 participants and the sub-sample involved 102 participants. Self-reported weight (non-corrected self-reported weight; non-cSrW) and height estimates (non-corrected self-reported height; non-cSrH) were collected. The measurements of weight (measured weight; mW) and height (measured height; mH) were taken. Using multiple regression equations, the corrected self-reported weight (cSrW) and height (cSrH) estimates were calculated. RESULTS: Non-cSrH was higher than mH in men on average by 2.4 cm and in women on average by 2.3 cm. In comparison to mW, non-cSrW was higher in men on average by 0.7 kg, while in women no significant difference was found (mean difference of 0.4 kg). In comparison to mBMI, non-cSrBMI was lower on average by $0.6kg/m^2$ in men and $0.7kg/m^2$ in women. No differences were observed in overweight and obesity incidence when determined by mBMI (68% and 19%, respectively), non-cSrBMI (62% and 14%, respectively), cSrBMI (70% and 22%, respectively) and pcSrBMI (67% and 18%, respectively). CONCLUSIONS: Since the results showed that the estimated self-reported heights, weights and BMI were accurate, the assessment of overweight and obesity incidence was accurate as well. The use of self-reported height and weight in the nutritional status assessment of elderly Poles on a population level is therefore recommended. On an individual level, the use of regression equations is recommended to correct self-reported height, particularly in women.