• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.269.1-269
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• 2001

• Proceedings of the Materials Research Society of Korea Conference
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• 2005.05a
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• pp.299-299
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• 2005

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2004.05a
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• pp.191-195
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• 2004

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2003.10a
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• pp.66-70
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• 2003

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.109-110
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• 2010

• Journal of the korean veterinary medical association
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• v.32 no.5
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• pp.285-316
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• 1996

소 해면형 뇌증(Bovine Spongiform Encephalpathy; BSE)이 처음 확인된 것은 1986년 11월이며, 영국에서의 최초발생을 시작으로 하여, 지난 10여년 동안 발생국가의 수는 다소 증가하고 있지만 전체적인 발생두수는 1993년을 정점으로하여 감소하는 추세를 보이고 있다. 아직까지도 확실한 병인체는 밝혀져 있지 않은 상태이며, 최초 확인당시 인체에의 감염 가능성은 없는 것으로 발표된 바 있으나, 지난 1996년 3월 20일, 영국정부 보건장관이 영구하원에서, 소 해면형 뇌증이 사람의 희귀한 뇌 질환인 크로이츠휄트-야곱병(CJD)의 새로운 스트레인(v-CJD)과 관련성이 있을 수 있다고 보고한 다음날, CNN 등 세계 각 매스컴을 통하여, '광우병 사람에게 전파될지도$\cdots$'(Mad cow illness may threaten humans)라는 제목으로 Top News로 보도되었으며, 수의학이나 의학적인 사실 확인의 여부를 떠나, 사회 경제적인 문제로 큰 놀라움과 많은 의문사항을 남겨둔 채, 국제적인 문제로 확대된 바있다. 본 편에서는, 소 해면형 뇌증 (BSE)과 관련, 영국의 광우병 파동이 일어난 지난 3월부터 지금까지 국내외 매스컴에 보도된 내용중 주요사항들을 스크랩하여 참고자료로 제공하고자 한다. 자료중에는 중복기사나 추측기사, 검증되지 아니한 오보, 지극히 개인적인 견해 등도 있을 수 있으며, 외신보도의 접수시간, 국내보도의 조간-석간, 지면구성, 수도권판과 지방판 등, 그리고 특히 병명이나 고유명사, 외래어 등의 전문용어 표기에 있어서 꼭 일치하지 아니하는 경우가 있을 수 있음을 참고로 하여야할 것이다.

• Journal of Korea Foundry Society
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• v.18 no.3
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• pp.240-245
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• 1998

In the view point of the environmental conservation and the energy reduction, the recycling of metal scrap is coming as one of the global subjects in the world. In this study, the movement of intermetallics with electromagnetic force in a melt of a scrap of Al-Si-Cu alloy (JIS ADC12), which was widely used in diecasting process, was investigated in order to eliminate the Fe element, which was usually accumulated in a scrap. In this study, we applied electromagnetic method to eliminate Fe element in ADC12 aluminum alloy scrap which contains 1.64wt.% Fe and the effects of electromagnetic force on the particle movement was visualized and confirmed by water modeling and experiment. As a result, the Fe intermetallic compounds are moved to the direction opposite to that of the electromagnetic force as the force applies, thus eliminated from the bulk metal. Therefore, the content of Fe in matrix decreased from 1.64wt.% to 0.45wt.%.

• Resources Recycling
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• v.18 no.5
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• pp.26-36
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• 2009

A recovery process of Ruthenium from waste electronic scrap has been investigated by means of nitric acid leaching as a part of development for scrap pretreatment process to obtaining an optimum conditions for removal of removing various impurities such as Pb, Bi, Zn, Al, Bi, Ag Fe, Co, Zr, Si. From the experiments, 90% of Pb leached with 250 g/l pulp density in 10-15% nitric acid. Leaching behavior of Ba was also similar to that of the Pb, but those of other metal impurities, such as Zn, Al, Bi, Ag, Fe, Co, Zr, showed different behavior, in which the dissolution rate increased as the concentration of nitric acid in solution is increased up to the 10% $HNO_3$ in solution and then it was constant above 10% $HNO_3$ concentrations. Meanwhile, the dissolution of Ru in $HNO_3$ solution was less then 100ppm, and that the total content of Ru in undissolved residue scrap was resulted in an increment of 50%.

• Resources Recycling
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• v.26 no.6
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• pp.3-9
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• 2017

In this study, plasma arc remelting behaviors according to arc current, arc voltage, and types of plasma gas were investigated using Kroll processed Ti sponges as anode. In the discharge pressure range of vacuum pump ($200{\sim}300kgf/cm^2$), the arc voltage did not vary greatly with the increase of discharge pressure at a given arc length. This means that the pressure in the vacuum chamber during operation hardly changes and the atmospheric pressure maintains. Under various conditions of arc currents (700~900A), the arc voltage slightly increased with arc current. The effects of anode materials and operational variables on the arc length-arc voltage relationship were compared with the results in previous studies. When the atmospheric gas changed from argon to helium, double effect of improvement on the output of the steady state was observed. The increase of output in the plasma arc device was accompanied by an increase in the melting rate of the Ti sponge and the quality of the ingot surface was also improved. The plasma arc remelting of the new scrap titanium and the old scrap zirconium alloy could result in the fabrication of an ingot with high surface quality.

• Resources Recycling
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• v.31 no.1
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• pp.46-55
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• 2022

The recycling of coated cemented carbide scraps is becoming increasingly significant for the recovery of rare metals. However, coatings consisting of Group IV and V transition metal nitrides are one of the challenging factors in obtaining high-purity materials. We investigated the structural, elastic, and mechanical properties of Group IV and V transition-metal nitrides (TiN, VN, ZrN, NbN, HfN, and TaN) using first-principle calculations. Convergence tests were performed to obtain reliable calculated results. The equilibrium structures of the nitrides were in good agreement with those of a previous study, indicating the reliability of the data. Group IV transition metal nitrides show a higher covalent bonding nature. Thus, they exhibit a higher degree of brittleness than that of Group V transition metal nitrides. In contrast, Group V transition metal nitrides show weaker resistance to shear loading and more ductile behavior than Group IV transition metal nitrides because of the metallic bonds characterized by valence electron concentration. The results of the crystal orbital Hamilton population analysis showed good agreement with the shear resistance tendencies of all transition metal nitrides.