• Title/Summary/Keyword: Inner Purity

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Effect of Ca Implantation on the Sintering and Crack Healing Behavior of High Purity Al2O3 Using Micro-lithographic Technique - I. Formation of Crack-like Pore and Its Morphological Evolution (Ion Implantation으로 Ca를 첨가한 단결정 Al2O3의 Crack-like Pore의 Healing 거동 - I. Crack-like Pore의 형성과 Morphological Evolution)

  • 김배연
    • Journal of the Korean Ceramic Society
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    • v.34 no.8
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    • pp.834-842
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    • 1997
  • Controlled Ca impurity implanted inner crack-like pore in the high purity alumina single crystal, sapphire, had been created by micro-fabrication technique, which includes ion implantation, photo-lithography, Ar ion milling, and hot press technique. The morphological change and the healing of cracklike pore in Ca doped high purity single crystal alumina, sapphire, during high temperature heat treatment in vacuum were observed using optical microscopy. The dot-like surface roughening was developed and hexagon like crystal appeared on inner surface of crack-like pore after heat treatment. Bar type crystals, probably CaO.6Al2O3, were observed on the inner surface after 1 hour heat treatment at 1, 50$0^{\circ}C$, but this bar type crystal disappeared after 1 hour heat treatment at 1, $600^{\circ}C$. This disappearance means that there should be a little increase of Ca solubility limit to alumina at this temperatures.

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Color Simulation to Demonstrate the Effects of the Filter Layer with $CoAl_2O_4$ on Inner Face of CRT Panel

  • Kim, Sang-Mun
    • Journal of Information Display
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    • v.6 no.3
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    • pp.26-29
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    • 2005
  • Nanosize cobalt aluminate($CoAl_2O_4$) power was coated as filter layer for us to improve the color purity and contrast performances on the inner face of CRT panel. We simulated color properties by measuring the transmittance and thickness of the coated filter layer. Contrast performance could be improved and color gamut was also changed by the selective light absorption of filter layer at 580${\sim}$605 nm.

A study on the production of chestnut powder in the inner layer of the chestnut from its treatment plant (II) - Physicochemical properties and baking properties of recovered chestnut powder - (밤가공공장의 밤껍질에서 밤분말의 생산에 대한 연구(II) - 밤껍질에서 분리회수한 밤분말의 특성과 제빵가능성 -)

  • 조숙자;정은희;전병관
    • Korean Journal of Rural Living Science
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    • v.10 no.2
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    • pp.78-84
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    • 1999
  • This study was performed to find out the usefulness of chestnut powder recovered from the inner layer, which used to be discarded. After the Physicochemical properties of the chestnut powder were examined, breads were prepared with 10-50% of chestnut Powder and the sensory quality was compared by QDA. Bread could be made even using up to 50% of chestnut powder, and in 20-30% of chestnut powder, the sensory quality was acceptable enough compared with wheat bread. Even though the low purity of the chestnut powder affected the flavor and color, the breads contained it were generally acceptable. Therefore, the chestnut powder recovered from the inner layer can be used as the effective food resource as itself, and with the higher purification to remove inner layer, it can be applied to more diverse food.

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Utilization of Biomass Resources(I) - HPLC Analysis of Chemical Components for Utilization of Chestnut Inner Bark - (Biomass 자원의 활용 (I) - 율추의 유효이용을 위한 화학적 조성분의 HPLC 분석 -)

  • Kim, Yun-Geun;Jo, Jong-Soo
    • Journal of the Korean Wood Science and Technology
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    • v.32 no.2
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    • pp.58-64
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    • 2004
  • For the utilization of chestnut inner bark as forest biomass, the diethyl ether solubles of hot water extract from chestnut inner bark was analyzed by HPLC. Each peak was identified by comparing with retention time of standard regents and their purity from obtained UV spectrum by RI detector. Identified 6 compounds were gallic acid, 3,5-dihydroxybenzoic acid, 2,4,6-trihydroxybenzoic acid and protocatecualdehyde as phenolic acids and aldehyde, and catechin and epicatechin as flavonoids.

Heat treatment induced morphological changes of $Ca^{++}$ implanted single crystal $Al_2O_3$ ($Ca^{++}$를 implant한 단결정 $Al_2O_3$에서 열처리에 의한 형태학적 변화)

  • 김배연
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.9 no.3
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    • pp.327-333
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    • 1999
  • Controlled Ca impurity implanted inner crack-like pore in the high purity alumina bi-crystal had been created by micro-fabrication technique, which includes ion implantation, photo-lithography, Ar ion milling, and hot press. The morphological change and the growth od crystals formed by heat treatment in Ca doped high purity single crystal alumina, were observed using optical microscopy. The dot was developed and hexagon like crystal appeared on inner surface of crack-like pore after heat treatment. Bar type crystals, probably CaO . $6Al_2O_3$, were observed on the inner surface of 100ppm Ca implanted specimen after 1 hour heat treatment at $1,500^{\circ}C$, but this bar type crystal disappeared after 1 hour heat treatment at $1,600^{\circ}C$. This disappearance means that there should be little increase of Ca solubility limit to alumina and/or changes of diffusion coefficient of Ca in alumina around this temperature.

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A study on Lee Gyubo's Poems Composed before his Travelling to Gangnam (이규보(李奎報)의 강남 유람 이전 한시 연구 - 내면의식을 중심으로 -)

  • Lee, Hee Young
    • (The)Study of the Eastern Classic
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    • no.59
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    • pp.33-56
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    • 2015
  • This paper examines how Lee Gyubo expressed his inner consciousness in his poems, confining chiefly to the works that he composed before his travelling to Gangnam. Criticism of his poems during that period should be subjected to the fact that he was critical-minded about social issues and was eager to succeed as well. He was spending his unlucky life as an intellectual while the military group seized political power. He could not overcome the prejudice of others and expressed his solitude in his lyrics in which he described things around him in detail. By doing this he tried to preserve his inner purity away from dusty world. On the other way he was very sensitive to the passing of time as he was always eager to succeed. Lee Gyubo edited Gangnam-jip after his travelling to Gangnam. After his travel, he sought a government post continuously, and lived a tough life until he was appointed to Jikhallim. What is remarkable is that he seldom expressed his solitude or frustration after his travel in spite of his tough life. It is presumed that he changed his mind to go with the times during his travel and there we can find the meaning of his travel to Gangnam.

A Consideration of Adolf Loos's Inner Spatial Conception and Furniture -Focused on the Use of 18C Anglo Saxon's Classical Furniture with "Affluent Interior" and That of Biedermeier- (아돌프 로스의 실내공간개념과 가구에 관한 고찰 -"풍요로운 내부"의 18세기 앵글로 색슨 및 비더마이어 고전가구 사용을 중심으로-)

  • 지수인
    • Korean Institute of Interior Design Journal
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    • no.21
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    • pp.154-165
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    • 1999
  • It is characteristic that houses designed by Adolf Loos show commonly a contradictory aspect between the exterior and interior. The exteriors of the houses are simple and on the other hand the interiors are affluent to the greatest degree. At that time, a stylized gorgeous decoration of the inner space had been prevailed in general among the historicism and Vienna Secession people, and such an inner spatial conception as by Loos must have brought a turning point for the development of a new inner spatial conception which can by itself be called revolutionary. This study is gong to clarify the fact that Loos has been in full consideration of the emotional side basically for the human being in the conception of inner space, by complementing the respect that his conception of the inner spatial composition, concentrating purity, comfort and classicalism on the furniture. Despite the independency of the Loos furniture is near copying, different from existing creative conception, it can be meaningful in respect that it creates out a rather accustomed and still a new space thought adding a little transformation to the existing classical furniture. So this study is going to re-establish the characteristics of the Loos furniture which work as the greatest impact in the composition of affluent inner space, the prototypical characteristics of that furniture, and the basical thinking system of Loos which can be found out in a little transformatiov.

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AlN preparation by Self-propagation High-temperature Synthesis (SHS) in Al-N2 and Al-N2-AIN system (Al-N2와 Al-N2-AlN계에서 고온자전연소법에 의한 AlN 합성)

  • 이재령;이익규;안종관;김동진;안양규;정헌생
    • Journal of Powder Materials
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    • v.11 no.4
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    • pp.294-300
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    • 2004
  • This study for preparation of aluminum nitride (AlN) with high purity was carried out by self-propagating high-temperature synthesis method in two different systems, $Al-N_{2}$ and $Al-N_{2}$-AlN, with the change of nitrogen gas pressure and dilution factor. On the occasion of $Al-N_{2}$ system, unreacted aluminum was detected in the product in spite of high nitrogen pressure, 10 MPa, This may be caused by obstructing nitrogen gas flow to inner part of molten and agglomerate of aluminum, formed in pre-heating zone. In $Al-N_{2}$-AlN system, AlN with a purity of 95% or ever can be prepared in the condition of $f_{Dil}\geq0.5$, $P_{N_{2}}\geq$ 1 MPa, and the purity can be elevated to 98% over in the condition of $f_{Dil}$ = 0.7 and $P_{N_{2}}$ = 10 MPa.

Analysis of 3-Dimensional Magnetic Field Distribution in C.P.M Considering Magnetization Vector Distribution (자화 벡터 분포를 고려한 C.P.M(Convergence Purity Magnet)의 3차원 자계 분포 해석)

  • Lee, Chol-Gyu;Kwon, Byung-Il;Park, Seung-Chan;Yoon, Tae-Ho
    • Proceedings of the KIEE Conference
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    • 2000.11b
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    • pp.241-243
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    • 2000
  • In this paper, we analyze three-dimensional magnetic field distribution of a convergence purity maget(C.P.M) which is used for a cathode ray tube. The magnetization vector distribution of the C.P.M is obtained from the result of magnetization process analysis using the 2D F.E.M. Then the motion of electron beam passing through the inner space of the C.P.M is determined and compared with experimental result.

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Semi-Insulating SiC Single Crystals Grown with Purity Levels in SiC Source Materials (고순도 SiC 파우더를 이용한 반절연 SiC 단결정 성장)

  • Lee, Chae Young;Choi, Jeong Min;Kim, Dae Sung;Park, Mi Seon;Jang, Yeon Suk;Lee, Won Jae;Yang, In Seok;Kim, Tae Hee;Chen, Xiufang;Xu, Xiangang
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.2
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    • pp.100-103
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    • 2019
  • The change in vanadium amount according to the growth direction of vanadium-doped semi-insulated (SI) SiC single crystals using high-purity SiC powder was investigated. High-purity SiC powder and a porous graphite (PG) inner crucible were placed on opposite sides of SiC seed crystals. SI SiC crystals were grown on 2 inch 6H-SiC Si-face seeds at a temperature of $2,300^{\circ}C$ and growth pressure of 10~30 mbar of argon atmosphere, using the physical vapor transport (PVT) method. The sliced SiC single crystals were polished using diamond slurry. We analyzed the polytype and quality of the SiC crystals using high-resolution X-ray diffraction (XRD) and Raman spectroscopy. The resistivity of the SI SiC crystals was analyzed using contactless resistivity mapping (COREMA) measurements.