• Title/Summary/Keyword: High-$T_{c}$

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Composite Effect of Ag and Au in the $Bi_{1.84}\;Pb_{0.34}\;Sr_{1.91}\;Ca_{2.03}\;Cu_{3.06}\;O_{10+\delta}$(110K Phase) High-Tc Superconductor (Ag와 Au가 혼합된 $Bi_{1.84}\;Pb_{0.34}\;Sr_{1.91}\;Ca_{2.03}\;Cu_{3.06}\;O_{10+\delta}$ 산화물 고온초전도체의 초전도특성)

  • 이민수
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.52 no.6
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    • pp.241-248
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    • 2003
  • $Bi_{1.84}Pb_{0.34}Sr_{1.91}Ca_{2.03}Cu_{3.06}O_{10+\delta}$ high $T_{c}$ superconductors containing Ag as an additive were fabricated by a solid-state reaction method. The superconducting properties, such as the structural characteristics, the critical temperatures, the grain size and the image of mapping on the surface were investigated. Samples with Ag and Au of 50 wt% each were sintered at various temperature(820~$850^{\circ}C$). The structural characteristics, the microstructure of surface and the critical temperature with respect to the each samples were analyzed by XRD and SEM, EDS and four-prove methode respectively. The critical temperature showed the result which the Ag additive samples are higher than Au additive samples. The microstructure of the surface showed the tendency which the Ag additive samples become more minuteness than Au additive samples.

Effect of Electrical Field on the Phase Transformation of 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 Single Crystals (단결정 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 의 상전이에 미치는 전장의 영향)

  • Lee, Eun-Gu
    • Korean Journal of Materials Research
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    • v.23 no.6
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    • pp.329-333
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    • 2013
  • The structural phase transformations of $0.7Pb(Mg_{1/3}Nb_{2/3})O_3-0.3PbTiO_3$ (PMN-0.3PT) were studied using high resolution x-ray diffraction (HRXRD) as a function of temperature and electric field. A phase transformational sequence of cubic (C)${\rightarrow}$tetragonal (T)${\rightarrow}$rhombohedral (R) phase was observed in zero-field-cooled conditions; and a $C{\rightarrow}T{\rightarrow}$monoclinic $(M_C){\rightarrow}$ monoclinic ($M_A$) phase was observed in the field-cooled conditions. The transformation of T to $M_A$ phase was realized through an intermediate $M_C$ phase. The results also represent conclusive and direct evidence of a $M_C$ to $M_A$ phase transformation in field-cooled conditions. Beginning from the zero-field-cooled condition, a $R{\rightarrow}M_A{\rightarrow}M_C{\rightarrow}T$ phase transformational sequence was found with an increasing electric field at a fixed temperature. Upon removal of the field, the $M_A$ phase was stable at room temperature. With increasing the field, the transformation temperature from T to $M_C$ and from $M_C$ to $M_A$ phase decreased, and the phase stability ranges of both T and $M_C$ phases increased. Upon removal of the field, the phase transformation from R to $M_A$ phase was irreversible, but from $M_A$ to $M_C$ was reversible, which means that $M_A$ is the dominant phase under the electric field. In the M phase region, the results confirmed that lattice parameters and tilt angles were weakly temperature dependent over the range of investigated temperatures.

Physical ppropperties in Rare-earth Compounds

  • Takashi, Suzuki
    • Proceedings of the Korean Vacuum Society Conference
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    • 1998.02a
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    • pp.18-18
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    • 1998
  • F First I will introduce our works how to improve the crystal growth t technique for Rare earth pnictides and chalcogenides. All these substances h have hi양1 vapor pressure and high melting print up to 3$\alpha$)()C. 까len we employ m the tungsten or molybden crucibles and enclose the sample by 빼e welding of m the lid with high current electron beam. We cannot elevate the temperature up t to 3$\alpha$)()C without suitable radiation shield because rate of radiation loss r rapidly increase in such a high temperature regions. There were no good r radiation shield but we discovered that the p-BN could work as an excellent r radiation shield after checking of the many substances. S Secondly I will show several interesting and unusual 뻐ysical properties of obtained crystals under high magnetic field, hi양1 pressure and also i including angle resolve photoemission spectroscopy. I will stress the p properties of the low carrier concentration with strong correlation on C댐, U USb and Yb4As3

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Fabrication and Characterization of High Performance Green OLEDs using $Alq_3$-C545T Systems ($Alq_3$-C545T시스템을 이용한 고성능 녹색 유기발광다이오드의 제작과 특성 평가)

  • Jang Ji-Geun;Kim Hee-Won;Shin Se-Jin;Kang Eui-Jung;Ahn Jong-Myong;Lim Yong-Gyu
    • Journal of the Microelectronics and Packaging Society
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    • v.13 no.1 s.38
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    • pp.51-55
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    • 2006
  • The green emitting high performance OLEDs using the $Alq_3$-C545T fluorescent system have been fabricated and characterized. In the device fabrication, 2-TNATA [4,4',4'-tris(2-naphthylphenyl-phenylamino)-triphenylamine] as a hole injection material and NPB [N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine] as a hole transport material were deposited on the ITO(indium thin oxide)/glass substrate by vacuum evaporation. And then, green color emission layer was deposited using $Alq_3$ as a host material and C-545T[10-(2-benzothiazolyl)-1,1,7,7- tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-[1]/benzopyrano[6,7,8-ij]-quinolizin-11-one] as a dopant. Finally, small molecule OLEDs with structure of ITO/2-TNATA/NPB/$Alq_3$:C545T/$Alq_3$/LiF/Al were obtained by in-situ deposition of $Alq_3$, LiF and Al as the electron transport material, electron injection material and cathode, respectively. Green OLEDs fabricated in our experiments showed the color coordinate of CIE(0.29, 0.65) and the maximum power efficiency of 7.3 lm/W at 12 V with the peak emission wavelength of 521 nm.

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Screening of BRCA1/2 Mutations Using Direct Sequencing in Indonesian Familial Breast Cancer Cases

  • Anwar, Sumadi Lukman;Haryono, Samuel J;Aryandono, Teguh;Datasena, I Gusti Bagus
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.4
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    • pp.1987-1991
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    • 2016
  • Breast cancer has emerged as the most prevalent cancer among women worldwide, including in Indonesia. The contribution of genes associated with high-risk breast-ovarian cancers, BRCA1 and BRCA2, in the Indonesian population is relatively unknown. We have characterized family history of patients with moderate- to high-risk of breast cancer predisposition in 26 unrelated cases from Indonesia for BRCA1/2 mutation analyses using direct sequencing. Known deleterious mutations were not found in either BRCA1 or BRCA2 genes. Seven variants in BRCA2 were documented in 10 of 26 patients (38%). All variants were categorized as unclassified (VUSs). Two synonymous variants, c.3623A>G and c.4035T>C, were found in 5 patients. One variant, c4600T>C, was found in a 38 year old woman with a family history of breast cancer. We have found 4 novel variants in BRCA2 gene including c.6718C>G, c.3281A>G, c.10176C>G, and c4490T>C in 4 unrelated patients, all of them having a positive family history of breast cancer. In accordance to other studies in Asian population, our study showed more frequent variants in BRCA2 compared to BRCA1. Further studies involving larger numbers of hereditary breast cancer patients are required to reveal contribution of BRCA1/2 mutations and/or other predisposing genes among familial breast cancer patients in Indonesia.

An Experimental Study of T-mode Vibration on the Diesel Power Plant (디젤 발전소의 T-mode 진동에 관한 실험적 고찰)

  • Lee, D.C.;Nam, T.K.;Bae, Y.C.;Kim, Y.H.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.411-416
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    • 2005
  • Nowadays, diesel power plant using low speed two stroke diesel engine is widely used in islands and restricted areas. Considerations were given to its benefit of high thermal efficiency, reliability and durability compared to the other prime movers. However, various types of engine vibration affect neighboring buildings to their structural vibration. For this, diesel power plant are held liable for the troubles caused by these vibration. These are mainly due to the X- and H-type engine vibrations which we excited by the X- and H- guide force moment. Authors have identified a structural vibration of new pattern called ‘T-mode vibration’ due to the torsional vibration of shafting system. In this paper, T-mode vibration is analyzed through an experimental method based on the global vibration measurement.

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Effects of Feeding Split Diets for a.m. and p.m. on Laying Hen Performance and Feed Cost (산란계에 대한 오전용 사료와 오후용 사료의 별도 급여가 산란능력과 경제성에 미치는 영향)

  • 이규호;정연종
    • Korean Journal of Poultry Science
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    • v.23 no.1
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    • pp.27-37
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    • 1996
  • This experiment was carried out to study the effects of feeding split diets for a.m. and p.m. on laying hen performance and feed cost with 480 ISA Brown layers for three periods during 32∼36, 52∼56 and 72∼76 wk of age, respectively. The control group(C) was fed a conventional single diet throughout the day and split diet groups (T$_1$, T$_2$, T$_3$, T$_4$ and T$\_$5/) were offered high energy-high protein-low Ca diets, and low energy-low protein-high Ca diets in a.m. and p.m., respectively. In split diet groups, feed intake, ME and CP consumption, and feed cost were significantly reduced(P<0.05) compared to the C, while the hen-day egg production was significantly improved. However, the average egg weight was not influenced by the feeding system. Due to the reduced daily feed, ME, and CP intakes, and the improved egg production, the conversions of feed, ME, CP, and feed cost required per kg egg mass were also significantly improved (P<0.05) in splits diet groups. Among split diet groups, the T$_2$ group fed the diet devoid of Ca supplement from the conventional laying hen diet in a.m., and the diet containing the Ca supplement 2 times the conventional diet in p.m., was superior in conversion of nutrients and feed cost per kg egg mass to the other split diet groups. It was concluded that daily feed and nutrients cousumption and daily feed cost could be reduced 5∼6% while hen-day egg production could be improved about 4%, so that about 10% of the feed and nutrients and feed cost per kg egg mass could be spared by introducing the split diet feeding for a.m. and p.m. based on T$_2$ treatment in laying hens.

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Process Development of Pyrolysis Liquefaction for Waste Plastics (폐플라스틱의 열분해 유화기술 개발)

  • Nho Nam-Sun;Shin Dae-Hyun;Park Sou-Won;Lee Kyong-Hwan;Kim Kwang-Ho;Jeon Sang-Goo;Cho Bong-Gyu
    • New & Renewable Energy
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    • v.2 no.2 s.6
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    • pp.118-125
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    • 2006
  • The target of this work was the process development of demonstration plant to produce the high quality alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70 t/y and the pilot plant of 360 t/y had been developed. Main research contents in this step were the process performance test of pilot plant of 360 ton/year and the development of demonstration plant of 3,000 t/y, which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/y showed about 80% yield of liquid product, which was obtained by both light gas oil(LGO) and heavy gas oil(HGO), The boiling point range distribution of LO product that was mainly consisting of olefin components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

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Process Development of Pyrolysis Liquefaction for Waste Plastics (폐플라스틱의 열분해 유화기술 개발)

  • Nho, Nam-Sun;Shin, Dae-Hyun;Park, Sou-Won;Lee, Kyong-Hwan;Kim, Kwang-Ho;Jeon, Sang-Goo;Cho, Bong-Gyu
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.523-526
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    • 2006
  • The target of this work was the process development of demonstration plant to produce the high quailty alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70t/y and the pi lot plant of 360 t/v had been developed. Main research contents in this step were the process performance test of pilot plant ot 360ton/year and the development of demonstration plant of 3 000 t/y which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/v showed components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

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Back-Extraction Processes of C.C.Lipase with Mediated AOT Reverse Micellar System

  • Lee, Sung-Sik;Kim, Bong-Gyu;Sung, Nak-Chang;Lee, Jong-Pal
    • Bulletin of the Korean Chemical Society
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    • v.25 no.6
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    • pp.873-877
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    • 2004
  • The relationship between the behaviors of c.c.lipase back-extraction and their percolation phenomena by using AOT reverse micellar systems (RVMS) has been studied by the addition of a small amount of additives to organic phase such as thiols and nonionic-surfactants focusing on micelle-micelle interactions. The values of ${\beta}_t$ defined by the variation of percolation processes and back-extraction behaviors of c.c.lipase have a good linear correlation. The hydrophobicity of additive molecules suppressing the cluster formation of reverse micelles (high values of ${\beta}_t$) improved the back-extraction behavior of c.c.lipase. The back-extraction fraction and its rate of c.c.clipase are increased with decreasing of the value of hydrophilic lipophilic balance (HLB) and increasing of the hydrophobicity per additive molecules added to reverse micellar systems (RVSM) in the same additives concentration.