• 제목/요약/키워드: segregation

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12%Cr 대형강괴(大型鋼塊)의 편석경감(偏析輕減)에 관(關)한 연구(硏究) (A Study on the Reduction of Segregation in Large 12%Cr Steel Ingot)

  • 은옥기;장윤석
    • 한국주조공학회지
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    • 제10권6호
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    • pp.520-527
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    • 1990
  • In order to reduce segregation in 12%Cr steel ingots of 60-100tons, numerical analysis by computer was applied to simulate solidification profiles and the profiles of liguid-solid coexisting zone in accordance with the ratios of H(Height) /D(diameter) of 100-ton ingot. The result is that the ratio of L(vertical length) /D(diameter) of liquid-solid coexisting zone was reduced in proportion to the decrease of H/D ratio. With the reduced H/D ratio(0.92) of ingot, the segregation in 60-ton ingot of 12% Cr steel can be much reduced and recovery was also improved by reducing ingot weight.

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극박 3%규소강에서 Mn이 황의 편석 거동 및 자성특성에 미치는 효과 (Effects of Mn on Sulfur Segregation and Magnetic Induction in Thin-gauged 3%Si-Fe Strip)

  • 조성수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.917-920
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    • 2001
  • Effects of addition of manganese and final reduction on segregation behavior of sulfur and final mangetic induction during final annealing have been investigated in the 300 ppm sulfur-contained 3% silicon-iron alloy strips with or without manganese. At the same concentration of sulfur, lower final reduction is favorable for final Goss texture. This is because the probability that the initial Goss grains survive under the highly segregated sulfur atmosphere and grow selectively within the segregated sulfur-free time range becomes higher. In the case of 3% silicon-iron with manganese, much lower magnetic induction was obtained, although the weak final reduction of 30% is given to the alloy, comparative to the 40%. This is because MnS particles acted as an reducer in the primary grain size.

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반용융 단조금형의 Gate 형상이 성형성에 미치는 영향 (The Effect of Gate Shape for Semi-Solid Forging Die on the Filling Limitation)

  • 손영익;강충길
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2000년도 추계학술대회 논문집
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    • pp.178-184
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    • 2000
  • To obtain high quality component with thixoforming process, it is important that the homegeneous distribution of solid particles without liquid segregation. In closed-die semi-solid forging process, liquid segregation is strongly affected by injection velocity than any other process variables because the material has to travel relatively long distance to fill the cavity through a narrow gate before solidification begins. The optimal injection velocity and die temperature were investigated to fabricate near-net-shape compressor component called Al frame.

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아스팔트 포장의 현장 밀도 추정을 위한 유전율 측정에 관한 연구 (On the Dielectric Constant Measurement for Asphalt Pavement Filed Density Estimation)

  • 김동식
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.338-340
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    • 2009
  • The asphalt pavement is usually non-uniform since achieving a non-segregated and homogeneous asphalt mixture is very difficult. The segregation can occur in the mixed material before it is fed onto the road and it become segregated as it is being placed onto the road surface. Note that this segregation determines the performance of the asphalt pavement. Hence, it is necessary to check the segregation by estimating the density of the asphalt pavement in the field. In this paper, a research on estimating the density of the asphalt mixture by measuring the dielectric constant of the material is conducted. An RF transceiver and an antenna are designed and tested to a series of asphalt density samples, and discussions are shown.

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슬라브 내부 크랙 및 중심편석 자동 판정 시스템 개발 (Automatic Measuring System Developement of Slab Inner Crack and Center Segregation)

  • 김성용;이수현;안인석
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2009년도 정보 및 제어 심포지움 논문집
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    • pp.332-334
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    • 2009
  • This thesis puts forward a suggestion of measuring inner crack and center segregation in steel processing by using scanner and image processing with sulfur printer. This is a system to scan according to the program, to choose the size of the specimen and to press the 'Measurement' button, come to a check result, to send the result to the server, and to save the data and check the measurement result in web. To sum up, there are three points in this system.

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쌍롤 주조법에 의해 제조한 알루미늄 합금의 미세조직 (Microstructures of Twin Roll Cast Aluminum Alloys)

  • 박종우;김희수;백남익
    • 한국주조공학회지
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    • 제16권2호
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    • pp.149-157
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    • 1996
  • Several aluminum based alloys were fabricated by a twin roll strip casting mill. As-cast microstructures and microsegregations of these aluminum alloys were investigated by means of optical microscope, scanning electron microscope and electron probe micro analysis. Clear distinction on microsegregation among the alloy systems was observed, that is, A1235 and A8011 alloys showed diffused segregation in the middle of the strip, while A3003 and A5086 alloys revealed a centerline segregation consisted of lamellar structure. Above center line segregation was resulted from enrichment of the alloying elements such as Mn, Fe, Cu, Si and eutictic reaction in central region of the alloy strip.

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Huntingtin-interacting protein 1-related is required for accurate congression and segregation of chromosomes

  • Park, Sun-Joo
    • BMB Reports
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    • 제43권12호
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    • pp.795-800
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    • 2010
  • Huntingtin-interacting protein 1-related (HIP1r) is known to function in clathrin-mediated endocytosis and regulation of the actin cytoskeleton, which occurs continuously in non-dividing cells. This study reports a new function for HIP1r in mitosis. Green fluorescent protein-fused HIP1r localizes to the mitotic spindles. Depletion of HIP1r by RNA interference induces misalignment of chromosomes and prolonged mitosis, which is associated with decreased proliferation of HIP1r-deficeint cells. Chromosome misalignment leads to missegregation and ultimately production of multinucleated cells. Depletion of HIP1r causes persistent activation of the spindle checkpoint in misaligned chromosomes. These findings suggest that HIP1r plays an important role in regulating the attachment of spindle microtubules to chromosomes during mitosis, an event that is required for accurate congression and segregation of chromosomes. This finding may provide new insights that improve the understanding of various human diseases involving HIP1r as well as its fusion genes.

Analysis and Calibration of Transient Enhanced Diffusion for Indium Impurity in Nanoscale Semiconductor Devices

  • Lee Jun-Ha;Lee Hoong-Joo
    • KIEE International Transactions on Electrophysics and Applications
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    • 제5C권1호
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    • pp.18-22
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    • 2005
  • We developed a new systematic calibration procedure and applied it to the calibration of the diffusivity, segregation and TED model of the indium impurity. The TED of the indium impurity was studied under 4 different experimental conditions. Although the indium proved to be susceptible to the TED, the RTA was effective in suppressing the TED effect and in maintaining a steep retrograde profile. Just as in the case of boron, indium demonstrated significant oxidation-enhanced diffusion in silicon and its segregation coefficients at the Si/SiO₂ interface were significantly below 1. In contrast, the segregation coefficient of indium decreased as the temperature increased. The accuracy of the proposed technique has been validated by SIMS data and 0.13-㎛ device characteristics such as Vth and Idsat with errors less than 5% between simulation and experiment.

대기압 MOCVD 시스템을 이용하여 Si 기판 위에 자발적으로 형성된 InAs 양자점에 대한 연구 (Epitaxy of Self-assembled InAs Quantum Dots on Si Substrates by Atmospheric Pressure Metalorganic Chemical Vapor Deposition)

  • 유충현
    • 한국전기전자재료학회논문지
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    • 제18권6호
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    • pp.527-531
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    • 2005
  • Fully coherent self-assembled InAs quantum dots(QDs) grown on Si (100) substrates by atmospheric pressure metalorganic chemical vapor deposition(APMOCVD) were grown and the effect of growth conditions such as growth rate and growth time on quantum dots' morphology such as densities and sizes was investigated. InAs QDs of 30 - 80 nm in diameters with densities in the range of (0.6 - 1.7) x $10^{10}\;cm^{-2}$ were achieved on Si substrates and InAs layer was changed from 2 dimensional growth to 3 dimensional one at a nominal thickness less than 0.48 ML. This is attributed to the higher ambient pressure of APMOCVD suppressing of In segregation from the 2 dimensional InAs layer. This In segregation looked to disturb the dot formation especially when the growth rate was low so that the dots became less dense and bigger as the growth rate was lower.

융액인상법에 의한 Nd;YAG 단결정 성장시 온도구배의 변화에 따른 결함거동 (Effect of Temperature Gradient on the Defects of Nd;YAG Single Crystal Grown by Czochralski Method)

  • 김한태;배소익;이상호;정수진
    • 한국세라믹학회지
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    • 제34권10호
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    • pp.1015-1020
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    • 1997
  • In the Nd;YAG crystal growth by Czochralski method, the relationship between the core formation and the solid-liquid interface was observed by controlling the temperature gradient in the furnace. When the crystal was grown along<111> direction, defects and core area were reduced as the temperature gradient increased. The optimum temperature gradient was found to be higher than 4$0^{\circ}C$/cm. The Nd3+ concentration analysis by ICP-Mass showed that the segregation coefficient was about 20% higher in the core region than core-free region, where the segregation coefficients of core region and core-free region were 0.22 and 0.18, respectively.

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