• Title/Summary/Keyword: C.M.R.T.

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Crystallographic Properties of ZnO/AZO thin Film Prepared by FTS method (FTS법으로 제작한 ZnO/AZO 박막의 결정학적 특성)

  • 금민종;강태영;최형욱;박용서;김경환
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.9
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    • pp.979-982
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    • 2004
  • The ZnO thin films were prepared by the FTS (facing target sputtering) system, which enables to provide high density plasma and a high deposition rate at a low working gas pressure. We introduced the AZO thin film in order to improve the crystallographic properties of ZnO thin film because of the AZO(ZnO:Al) thin film has an equal crystal structure to the ZnO thin film. ZnO/AZO thin films were deposited at a different oxygen gas flow ratio, R.T. 2mTorr working pressure and a 0.8A sputtering current. The film thickness and c-axis preferred orientation of ZnO/AZO/glass thin films were measured by ${\alpha}$-step and an x-ray diffraction (XRD) instrument. In the results, we could prepare the ZnO thin film with c-axis preferred orientation of about 6$^{\circ}$ on substrate temperature R.T. at O$_2$ gas flo rate 0.5.

Enzyme Kinetics Based Modeling of Respiration Rate for 'Fuyu' Persimmon (Diospyros kaki) Fruits (효소반응속도론에 기초한 단감의 호흡 모델에 관한 연구)

  • Ahn, Gwang-Hwan;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
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    • v.36 no.4
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    • pp.580-585
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    • 2004
  • Respiration of 'Fuyu' persimmon (Diospyros kaki) fruits were measured in terms of oxygen consumption rate and carbon dioxide evolution by closed system experiments at 0, 5, and $20^{\circ}C$. Enzyme kinetics-based respiration model was used to describe respiration rate as function of $O_2\;and\;CO_2$ gas concentrations $(R=V_m[O_2]/K_m+(1+[CO_2]/K_i)[O_2])$, and Arrhenius equation was applied to analyze temperature effect. $V_m\;and\;K_m$ increased, while $K_i$ decreased, with increasing temperature. $K_m\;of\;O_2$ consumption was greater than that of $CO_2$ evolution at equal temperature. Inhibitory effect of reduced $O_2$ level on $O_2$ consumption was more prominent than that on $CO_2$ evolution. Activation energy of respiration decreased with reduced $O_2$ and elevated $CO_2$ concentrations. Activation energy of $CO_2$ evolution was greater than that of $O_2$ consumption. Permeable package experiments verified respiration model parameters by showing good agreement between predicted and experimental gas concentrations in package.

Thermally Stimulated Exoelectron Emission from LiF(Mg,Cu,Na,Si) Phosphor (LiF(Mg,Cu,Na,Si)형광체의 열자극엑소전자방출)

  • Doh, Sih-Hong;Jeong, Jung-Hyun;Aoki, M.;Nishikawa, T.;Tamagawa, Y.;Isobe, M.
    • Journal of Sensor Science and Technology
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    • v.3 no.2
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    • pp.11-15
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    • 1994
  • The TSEE characteristics of LiF(Mg,Cu,Na,Si)phosphor for gamma and beta rays are described. The TSEE glow curve of this phosphor showed 5 peaks in the range from $20^{\circ}C$ to $400^{\circ}C$ and its main peak appeared at $240^{\circ}C$. The sensitivity of the phospor for $^{60}Co$ gamma rays was about 450counts/mR. TSEE energy dependence for various beta radiation was nearly constant (${\pm}10%$) in the mean beta particle energy range from 0.02MeV to 0.8MeV. The efficiency of TSEE of the phosphor for beta radiation was $(2{\sim}15){\times}10^{-3}$.

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Effect of the Electrode Type on the Dielectric and Piezoelectric Properties of Piezoelectric PMN-PZT Single Crystals (압전 PMN-PZT 단결정의 유전 및 압전 특성에 미치는 전극 종류의 영향)

  • Lee, Jong-Yeb;Oh, Hyun-Taek;Choi, Kyoon;Lee, Ho-Yong
    • Journal of the Korean Ceramic Society
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    • v.52 no.1
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    • pp.77-82
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    • 2015
  • The effect of the electrode type on the dielectric and piezoelectric properties of $Pb(Mg_{1/3}Nb_{2/3})O_3-PbZrO_3-PbTiO_3$ (PMN-PZT) single crystals was investigated in an effort to improve their properties for various piezoelectric applications. First, three different types of PMN-PZT single crystals [PMN-PZT-A (piezoelectrically soft type; dielectric constant ~ 10,000), PMN-PZT-B (piezoelectrically soft type; phase-transition temperature between the rhombohedral and tetragonal phases ($T_{RT}$) ~ $145^{\circ}C$), PMN-PZT-C (piezoelectrically hard type; high mechanical quality factor ($Q_m$) ~ 1,000)] were fabricated using the solid-state single crystal growth (SSCG) method. Then, four different types of electrodes [sputtered Au, sputtered Cr/Au, sputtered Ti/Au, and fired Ag] were formed on the single crystals, and their dielectric and piezoelectric properties were measured. The single crystals with a sputtered Ti/Au electrode showed the highest dielectric and piezoelectric constants but the lowest coercive electric field ($E_C$). The single crystals with a fired Ag electrode showed the lowest dielectric and piezoelectric constants but the highest coercive electric field ($E_C$). This dependence on the type of electrode was most significant in the piezoelectrically hard PMN-PZT-C single crystals. However, the effects of the electrode type on the phase transition temperatures ($T_C$, $T_{RT}$) and dielectric loss were negligible. These results clearly demonstrate that it is important to select an appropriate electrode so as to maximize the dielectric and piezoelectric properties of single crystals in each type of piezoelectric application.

Study on Precipitation and Mechanical Properties of High Strength Invar Alloy (고강도 인바합금의 석출거동과 기계적 특성 연구)

  • Jeong, J.Y.;Lee, K.D.;Ha, T.K.;Jeong, H.T.
    • Transactions of Materials Processing
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    • v.17 no.7
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    • pp.507-510
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    • 2008
  • Effect of V addition on the precipitation behavior and strength of Fe-36Ni based high strength Invar alloy for power transmission wire was investigated. Fe-36Ni Invar alloy plates were fabricated using conventional ingot casting followed by hot rolling. High strength can be obtained through precipitation hardening and strain hardening by cold rolling. Simulation using FactSage$^{(R)}$ revealed that equilibrium phases which can be formed are two kinds of MC-type precipitates, $Mo_{2}C$ and $M_{23}C_6$ carbide. The latter stoichiometric carbide was expected to be formed at relatively lower temperature of $800^{\circ}C$.

Studies on the Controlled Release Fertilizer METAP Application on Paddy Rice (1972) (수도에 대한 완효성비료 METAP의 비효시험(1972))

  • Lee, E.W.;Ahn, S.B.;Lee, M.H.;Lee, Z.Y.;Song, N.H.;Kwon, S.M.;Kim, C.Y.;Choe, B.C.;Chung, H.S.;Cho, B.O.;Lee, I.J.;Park, C.S.;Ko, C.S.;Park, K.H.;Chung, S.C.;Chung, H.S.;Lee, H.D.;Park, S.T.;Lee, H.S.;Choe, S.R.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.13
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    • pp.107-118
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    • 1973
  • Experiments were carried out to study the effectiveness of METAP as a slow released fertilizer on the growth, grain yield and its components of paddy rice, and to compare its effects with those of single fertilizers in the fields of 3 Crop Experiment Stations and 7 provincial Offices of Rural Development. The effectiveness of METAP seems to be different according to the physical and chemical characteristics of soil, the time of application, climatic conditions, variety and cultural methods. Therefore, the experimental results obtained from the above experiment are summurized as follows: 1. When METAP was applied into sandy soil, grain yield was increased due to increase of the number of panicles, and split application of METAP was more effective than basal only. However, in the reclaimed soil, not heavily percolated soil and fertile soil, no differences were observed between MET AP and single fertilizer applied plot. 2. When a rice variety, 'TONGIL' which is sensitive to the low temperature and produce higher yield in the early transplanting, was not transplanted early and air temperature is relatively lower during the ripening stage, the percentage of ripened grains and 1,000 grains weight were not higher in the METAP applied plots than in the single fertilizer applied plots.

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Flow cytometric analysis of apoptosis in mouse thymocytes by galectin-3 (유세포 분석기를 이용한 galectin-3에 의해 유도된 흉선세포의 apoptosis 분석)

  • Kim, Tae-jung;Woo, Hee-jong
    • Korean Journal of Veterinary Research
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    • v.39 no.6
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    • pp.1112-1118
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    • 1999
  • Galectin-3 plays an important role in cell development, differentiation and cancer metastasis, including cell-cell/extracellular matrix (ECM) interactions and is supposed to have an effect of apoptosis on T-cells in thymic clonal selection. In this study, to know the effect of galectin-3 on thymocyte development, we used recombinant human galectin-3 (rHgal-3) from Escherichia coli, JM105, which was inserted with human gal-3 gene-transformed plasmid vector (prGal-3) to express human galectin-3. Expressed rHgal-3 was confirmed by western blot using the culture supernant of hybridoma (M3/38) producing monoclonal antibody to human galectin-3. Sepharose gel affinity chromatography was used to purify the expressed rHgal-3. Thymocytes and hepatocytes from 6-week-old male BALB/c mice were incubated with rHgal-3 and showed marked increase of apoptotic population on analysis using flow cytometry with 7-AAD in a dosedependent manner. However, rHgal-3 failed to induce apoptosis on hepatocytes. Interestingly, this apoptotic effect was not inhibited by lactose, a specific lectin domain inhibitor. From these results, we concluded that extrinsic -3 induces apoptosis on mouse thymocytes, and galectin-3 may have an apoptotic effect on T-cells in thymic clonal selection.

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Estimating of Pollutant Load at Paddy Field Area (광역논에서의 오염물질 부하량 산정)

  • Kim, Byoung-Hee;Yoon, Chun-Gyeong;Hwang, Ha-Sun
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2001.10a
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    • pp.509-512
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    • 2001
  • In this study, pollutant load from paddy field was estimated by regression equation from 5 to 8 in 2001. During study period, total rainfall was 511.3mm and runoff discharge was 968.71mm. Regression equation between flow rate(m3/s) and pollutant loading rate(g/s) is exponential relationship. For site 1, coefficient of determination (R2) for $COD_{cr}$, T-P, T-N were 0.7068, 0.8441, 0.6806 respectively and site 2, 0.9369, 0.8855, 0.4262 respectively. Considering unit loads, Jun was the highest valus as 13.85 $COD_{c}kg/km2/day$, 0.24 T-Pkg/km2/day, 1.22 T-Nkg/km2/day. Until study period, total $COD_{cr}$ load estimated regression equation is 19.32kg/km2/day and, T-P, T-N were 0.264, 1.88 respectively

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Combustion Characteristics of HCNG Burner System with Tail Gas Addition (HCNG용 버너시스템에서 Tail Gas 첨가 시 연소특성)

  • Han, J.O.;Lee, J.S.;Kim, H.T.;Kim, S.M.;Lee, Y.C.;Kim, Y.C.;Hong, S.H.
    • Journal of the Korean Society of Combustion
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    • v.20 no.2
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    • pp.36-39
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    • 2015
  • The combustion characteristics of metal fiber burner fueled natural gas with tail gas produced from reforming process were analyzed on the point of flame stability and excess air conditions. Also, it was analyzed the effect of energy efficiency improvement due to decrease the fuel input in reforming system by using residue gases. As a results, it was confirmed that tail gas including hydrogen, CO and $CO_2$ could be directly injected without any change of air control system in natural gas burner and also energy efficiency was increased up to 30% maintained stable combustion.

Marine Algal Flora and Community Structure in Kijang on the Southern East Coast of Korea (부산시 기장군 연안의 해조상 및 군집 특성)

  • Choi, Chang-Geun;Chowdhury, M.T.H.;Choi, In-Young;Hong, Yong-Ki
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.3
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    • pp.133-139
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    • 2010
  • Marine algal flora and community structure were investigated at four sites in Kijang area on the southern east coast of Korea in August 2006 and August 2009, respectively. A total of 54 seaweeds including 6 green, 10 brown, 38 red were collected and identified. Of 54 seaweeds, 35 species were found throughout the survey period. Mean biomass in wet weight was from $616.0\;g\;m^{-2}$ to $1,462.4\;g\;m^{-2}$2 in 2006, and $354.8\;g\;m^{-2}$ to $965.6\;g\;m^{-2}$ in 2009. Maximum biomass was recorded at Mundong site, and minimum was recorded at Seoam (2006) and Dongbaek (2009) sites. The flora investigated (2006, 2009) could be classified into six functional groups such as coarsely branched form (58.7%, 58.1%), thick leathery form (10.9%, 11.6%), filamentous form (13.0%, 9.3%), crustose form (6.5%, 9.3%), sheet form (6.5%, 7.0%) and jointed calcareous form (4.3%, 4.7%) during survey period. The R/P, C/P and (R+C)/P values reflecting flora characteristics were 4.00, 0.75 and 4.75 at 2006, and 5.17, 1.00 and 6.17 at 2009, respectively. Therefore, the number of marine algae species and biomass in Kijang area were similar when they were comparing with the previous data. It suggest that any changes of seaweed diversity have not been observed in Kijang coastal area before and after the anthropogenic construction between 2006 and 2009.