• Title/Summary/Keyword: Faction

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The Structural properties of BSCT thick films fabricated by screen-printing method (Screen-printing법으로 제작한 BSCT 후막의 구조적 특성)

  • Heo, Young-Sik;Lee, Sung-Gap;Park, Sang-Man;Lee, Young-Hie
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.545-548
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    • 2002
  • $(Ba_{0.6-x}Sr_{0.4}Ca_x)TiO_3$(BSCT) (x=0.10, 0.15, 0.20) powders were prepared by the sol-gel method and BSCT thick films were fabricated by the screen-printing method. The structural properties as a faction of the composition ratio were studied. As a result of the differential thermal analysis (DTA), exothermic perk was observed at around $860^{\circ}C$ dne to the formation of the polycrystalline perovskite phase. The BSCT thick films sintered at $1350^{\circ}C$ for 2h showed the average grain size of $2{\sim}7{\mu}m$. The average thickness of BSCT thick films, obtained by 3 times of screen-printing, was approximately $85{\mu}m$.

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Antioxidative Activity of Extrcts from Fruit of Curdrania tricuspidata (꾸지뽕나무 열매 추출물의 항산화 활성)

  • 차재영;조영수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.3
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    • pp.547-551
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    • 2001
  • The comparative activities of acetone, ethanol, and aqueous fractions extracted from fruit powder of Cudrania tricuspidata by different temperature were tested by in vitro experimental models; peroxidation of linoleic acid and autooxidation of rat hepatic and renal microsomes by using thiobarbituric acid (TBA) for assay of free malondialdehyde production, and scavenging activities of free radicals by DPPH (α, α'-diphenyl-β-picrylhydrazyl). In DPPH method, acetone fraction extracted at 30℃ showed the highest free radical scavenging activities and acetone fractions extracted at 30℃ and 60℃ and ethanol fraction extracted at 30℃ showed stronger than BHT (butylated hydroxitoluene) although used ten-fold lower concentrations. In thiocyanate method used linoleic acid an inhibitory effects of all fractions showed higher than control treatment. TBA method used linoleic acid showed the highest antioxidative activity in acetone fraction extracted at 30℃ and 60℃. an inhibition activity against lipid peroxidation in hepatic microsomes of rats showed the highest at acetone faction extracted at acetone fraction among extracted fractions was shown to be the most potent antioxidative properties and this action was more potent in fractions extracted at 30℃ than those extracted at 60℃.

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An Ethnographic Analysis on Affective Aspects of Apparel Buying Behavior (의류구매행동에서의 감정적 측면에 관한 정성적 분석 - 문화기술학적 접근방법으로 -)

  • 황연순
    • Journal of the Korean Society of Costume
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    • v.31
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    • pp.75-87
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    • 1997
  • The purpose of this study was to investigate the experiential aspects of consumer in the ap-parel buying process especially the affective aspects. An ethnographic approach is a kind of qualitative analysis or naturalistic inquiry be-ing adopted by studies of anthnopology and consumer behavior,. Data were collected via doing participant observation interview field notes and recording for three months from fe-male students of universities in Pusan. Results were as following: First consumers experienced the various kinds of affection in the apparel buying pro-cess such as satisfaction pleasure/refresh-ment interest/attraction pride conspicous-ness impulse neglect prostration anxiety ir-ritation and dispiritedness. Second especially they were felt satis-faction and conspicousness by the atmosphere of store pleasure by the smell of store and impulse by nostalgia in apparel buying process. Also negative affections felt in the process such as neglect prostration anxiety and irri-taton had a great influence to apparel buying behavior. This study was to serve as a pilot study we wished to fortify the methodology of qualitat-ive analysis to identify themes and to de-velop hypothesis for further study.

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A Study on the Wearing and Purchasing Hanbok of Korean Urban Women (한국 도시 여성의 한복 착용 및 구매 실태)

  • 최선형;정인희;강순제
    • Journal of the Korean Society of Costume
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    • v.37
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    • pp.33-46
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    • 1998
  • The purposes of present study were (1) to examine the actual condition of wearing and purchasing Hanbok, (2) to investigate the effect of demographic variables on the wearing and purchasing Hanbok and (3) to identify the dissatisfaction with Hanbok. Data were collected from 702 females, age 20 or older, residing in Seoul, Taejon, Pusan and were analysed. Results of this study were as follows : (1) Korean urban women possess from one to three Traditional Dress and wear Hanbok in one to three during one year for special days. (2) The demographic variables that affect on wearing and purchasing Traditional Hanbok were age, income, family make-up and growing region. (3) One among the four Korean urban women possesses a Deformed Hanbok. And Korean women wears Deformed Hanbok for both daily life and special days. (4) The store that most women purchase Hanbok was order-made store near the house. The income affected on the store that purchaser selects significantly. (5) Three factors consisting of dissatis-faction with Hanbok were dissatisfaction with 'wearing', 'purchasing' and 'diversity of Hanbok design'. (6)Significant levels of correlations existed between the degrees of wearing Hanbok and the dissatisfaction.

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Effect of Microstructure on the Damping Capacity of 12Cr Martensitic Heat-resisting Steel (12Cr 마르텐사이트계 내열강의 감쇠능에 미치는 미세조직의 영향)

  • Lee, S.M.;Kang, C.Y.
    • Journal of Power System Engineering
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    • v.14 no.2
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    • pp.78-83
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    • 2010
  • This study was carried out to investigate the effect of microstructure on the damping capacity of 12Cr martensite heat-resisting steels, in case of the specimen with martensite phase contained the volume faction of ferrite phases, under 5%. The damping capacity was decreased with the increase of solution treatment temperature and time. While it was increased with the increase of tempering temperature and time. The damping capacity was higher in case of specimen with martensite single phase structure than the specimen with martensite phase contained of ferrite phases.

Antioxidative Activity on Human Low Density Lipoprotein(LDL) Oxidation by 2,6-Dimethoxyphenol Purified from Bacillus sp. KS-96

  • Ho, Ryu-Beung;Lee, Young-Sook
    • Journal of Life Science
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    • v.9 no.2
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    • pp.57-61
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    • 1999
  • This study was designed to develope the antioxidative activity on oxidation of human low density lipoprotein(LDL) from marine microbials. Bacillus KS-96 producign antioxidant have been isolated and identified from seawater, Bacillus sp. KS-96. The optimal medium pH was 7.0 and incubation temperature was 30$^{\circ}C$. The antiosidant of potential substance produced extracellularly in the culture broth by Bacillus sp. KS-96 was obtained by elution of silica gel culumn chromatography with hexane, ethylacetate and water. The ethylacetate faction are shown at highest level of antioxidant activity using thiocyanate method among them. By IR, NMR, and GC/MS, antioxidant purified from ehtylacetate fraction was identified and named as 2,6-dimethoxyphenol. 2,6-dimethoxyphenol inhibited the metal mediated oxidation of human LDL at concentration of 50∼100 ${\mu}$g/mL in the presence of 5uM CuSO4 with macrophage or J774 cells.

Phytochemical and Antioxidant Activity of Spathodea campanulata P. Beauvois. Growing in Egypt

  • Nazif, Naglaa M.
    • Natural Product Sciences
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    • v.13 no.1
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    • pp.11-16
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    • 2007
  • Alcoholic extract of Spathodea campanulata P. aerial parts, and two of the isolated fractions from celite column showed strong antioxidant activity (92, 94 & 89% RSA, Radical Scavenging Activity). Phytochemical investigation of chloroform/EtOAc faction of this column led to the isolation of phenolic acids, caffiec acid (1), and ferulic acid (2), fraction EtOAc/MeOH on further fractionation afforded 3 Flavonoids, kampferol 3-O-glucoside (3), quercetin 3-methyl ether (4) and 8-methoxy kampferol 3-O-glucoside (5). The isolated constituents were identified by co chromatography with authentic samples, TLC, PC., UV, MS and $^1H-NMR$. Also the lipoidal matter of the plant was studied. The unsaponifiable matter was found to be mixture of hydrocarbons from $(C_{14}-C_{28})$, cholesterol, campasterol, stigmasterol, and ${\alpha}-amyrin$. Fatty acid methyl esters were found to contain 12 fatty acids. The fatty acids containing $C_{18}$ farmed ca.65% of the total mixture.

The Calculation of Radiative Heat Transfer from Turbulent Diffusion Flames Using the Finite Volume Method (유한 체적법을 이용한 난류 확산 화염에서의 복사 열전달 계산)

  • Kim S. H.;Huh K. Y.
    • 한국전산유체공학회:학술대회논문집
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    • 1997.10a
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    • pp.106-112
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    • 1997
  • The effects of radiative heat transfer are investigated in a turbulent combustion flow field with highly non-adiabatic flames. Turbulent combustion is modeled by the $k-{\varepsilon}-g$ model and a one step irreversible reaction scheme for the combustion chemistry. The radiative trasport equation is solved by the finite volume method considering the radiative transfer from $CO_2,\;H_{2}O$ and soot only. Gray gas is assumed to calculate the radiative properties of $CO_2\;and\;H_2O$. A two-equation soot formation model is applied to predict soot volume faction distribution. All equations are solved in a coupled manner and the numerical results are compared with available experimental data.

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NUMERICAL ANALYSIS OF MULTIPHASE FLOW BY NUFLEX (NUFLEX의 다상유동 해석)

  • Son, Gi-Hun;Suh, Young-Ho;YU, Tae-Jin;Hur, Nahm-Keon
    • 한국전산유체공학회:학술대회논문집
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    • 2007.04a
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    • pp.95-98
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    • 2007
  • A general purpose program NUFLEX has been extended for two-phase flows with topologically complex interface and cavitation flows with liquid-vapor phase change caused by large pressure drop. In analysis of two-phase flow, the phase interfaces are tracked by employing a LS(Level Set) method. Compared with the VOF(Volume-of-Fluid} method based on a non-smooth volume-fraction function, the LS method can calculate an interfacial curvature more accurately by using a smooth distance function. Also, it is quite straightforward to implement for 3-D irregular meshes compared with the VOF method requiring much more complicated geometric calculations. Also, the cavitation process is computed by including the effects of evaporation and condensation for bubble formation and collapse as well as turbulence in flows. The volume-faction and continuity equations are adapted for cavitation models with phase change. The LS and cavitation formulation are implemented into a general purpose program for 3-D flows and verified through several test problems.

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Optimation of Reactor Control System by using Random Noise (랜덤 잡음을 이용한 원자로의 제어계 최적안전운전에 관한 연구 (1))

  • 고병준;신재인
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.6 no.1
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    • pp.1-11
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    • 1969
  • Reactor power frequency spectrum measurements at various power levela-OW, 1KW, 50KW, 100KW were made with TRIGA-MARK-II. An ion chamber was exposed to reactor flux, and the fluctions in its output current were analyed in a tunable bandpass filter to get the frequency spectrum of these fluctuation. The measured frequency spectrum of pile determined the modules of modules of zero power transfer function and indicated a prompt neutron mean life time of (7.90$\pm$1.62)X10 sec based on effective delayed neutron faction of 0.0075. The absolute value of reactor power obtained by noise analysis agreed within 5% with the power meter indication at the power below 10Kw.

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