• Resources Recycling
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• v.20 no.4
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• pp.3-22
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• 2011

Until recently, domestic high grade limestone have mainly mined so high grade limestone deposits have reduced. Because of exhaustion of high grade limestone, mine of limestone have moved from ground to deep position, the grade of limestone become lower because the amount of impurities and colored mineral increased as mining position become deeper. This paper was described about grade improvement of limestone to make a high grade limestone and suitable quality of limestone products by analysis of ore genesis and characteristics, supply and demand situation, use patterns and application standards of domestic lime-stone.

• 프린팅코리아
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• s.29
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• pp.166-167
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• 2004

일본에서는 10년 전에 화제가 되었다가 자취를 감추었던 고품위 인쇄가 최근 들어 새로운 사고방식의 기술로 주목을 받고 있다. 인쇄 회사마다 품질관리 방식은 제각기 다를 뿐만 아니라 한 공장 내에서도 각각의 인쇄기 설정을 사내 표준으로 통일해 두고 같은 품질의 인쇄물을 얻을 수 있는 것이 가장 좋은 방법이지만 기계마다 설정을 바꾸지 않으면 안 되는 경우도 있다. 그렇다면 같은 회사에서도 여러 개의 공장을 가지는 경우에는 공장마다 그 관리 방법에서 차이가 나올 수 있어 항상 같은 품질의 인쇄물을 제작하기란 상당히 어려운 일이다. 이에 본지에서는 고품위 인쇄로 공장의 기술력 향상과 품질 향상을 꾀하고 있는 일본 인쇄 회사의 사례를 소개한다.

• Mineral and Industry
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• v.17 no.2
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• pp.68-76
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• 2004

• Proceedings of the Petrological Society of Korea Conference
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• 2004.05a
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• pp.120-123
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• 2004

• Proceedings of the Mineralogical Society of Korea Conference
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• 2004.05a
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• pp.120-123
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• 2004

• Proceedings of the Petrological Society of Korea Conference
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• 2009.05a
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• pp.26-28
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• 2009

• Resources Recycling
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• v.23 no.4
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• pp.12-20
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• 2014

The objective of this study is to investigate the possibility of beneficiation of low grade iron ore. Iron ore A might be upgraded by the mineral liberation effect, while iron ore B was expected to be difficult to upgrade. However, the Fe contents of iron ore B were increased from 68% to 81% by the heat treatment process. Iron ore A was found to possibly enrich the Fe components through the physical separation process, such as magnetic separation, floatation and gravity concentration. In the case of iron ore B, it was possible to concentrate the Fe components through the heat treatment process.

• Journal of the Mineralogical Society of Korea
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• v.30 no.4
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• pp.137-147
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• 2017

Sericite is a clay mineral that has a wide applications in the industry, depending on its purity. To maintain sericite's purity as high as possible it is necessary to remove its gangue minerals or control their contents prior to use for high value-added products and applications. In this study, the wet beneficiation of sericite by applying selective grinding and sedimentation techniques, were investigated. The ore mineral was composed mainly of sericite, quartz and calcite. Analysis showed that the content of sericite increased along with the particle size decrease, but the contents of impurity minerals as quartz and calcite were tended to decrease relatively with particle size decrease. The results of liberation tests using an attrition scrubber showed that the increase in residence time and slurry density have increased the generation of fine particles in -325 mesh size range. It was observed, however, that the contents of impurities such as quartz and calcite in such fine particles also increased during prolonged scrubbing. In the dispersed form without breaking, the yield of the recovered concentrate was 15.4 wt% and the $K_2O$ content was 9.84 wt%, after the dispersed slurry was allowed to settle for 20 minutes. On the other hand, the concentrate yield was increased to 23.4 wt% after 10 minute attrition scrubbing and 40 minute sedimentation, while its $K_2O$ content was decreased to 9.71 wt%. Most of final products were observed as platelet-shaped particles containing Si, Al and K which are main component of sericite.

• Journal of Hospice and Palliative Care
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• v.16 no.4
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• pp.223-231
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• 2013

Purpose: This study was conducted to explore how nurses' attitude toward dignified death and moral sensitivity affect their end-of-life care performance. Methods: Study participants were 172 nurses who work at university hospitals in a metropolitan city in Korea. Data were collected from June 20 through August 13, 2012 using the Dignified Death Scale, Moral Sensitivity Scale, and End-of-Life Care Performance Scale. Data were analyzed using the SPSS/WIN 19.0 program. Results: Factors affecting nurses' end-of-life care performance included moral sensitivity, dignified death and education level. Conclusion: Moral sensitivity, dignified death and education level should be considered when developing an educational program for nurses' end-of-life care performance.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.366-366
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• 2009

후면접합 태양전지는 상용 태양전지의 수평전류 손실(lateral current loss) 이 없으며, 전면전극에 의해 발생하는 그림자 손실(shading loss) 줄인 고효율 태양전지의 하나이다. 생성된 반송자가 후면에 위치한 전극에서 수집되기 때문에 효율향상을 위해서는 불순물에 의한 재결합을 줄이는 것이 중요하다. 따라서 Gettering 은 높은 소수반송자 수명(life-time)을 가지는 고품위 실리콘 기판은 고효율 실리콘태양전지 제작을 위한 중요 요소 기술이다. 본 연구에서는 n-type c-Si 기판을 이용한 고효율 실리콘 이종접합 태양전지제작을 위해 external gettering 공정을 이용하여 고품위 실리콘 기판을 제작하였다. POC13 doping process 의 온도, 시간을 변화시킴으로써 이에 따른 변화를 관찰하였다. 주사전자현미경(SEM)를 통해 etch pit 을 확인 했으며,Four point probe 를 통해 면저항을 측정, 인(P)의 농도를 계산 하였다. 계산된 면저항을 통해 인(P)의 확산 깊이를 계산하였다. Iodine passivation 된 시편을 Qusi-steady state photoconductance (QSSPC)를 이용하여 소수반송자 수명을 측정함으로써 gettering 에 의한 bulk lifetime 향상 효과를 관찰하였다.