• Title/Summary/Keyword: Seperation

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A Study on the Recovery of Rare Earth Minerals from Ja-Eun Iron Ore. (자은철광석으로부터 희토류광물 회수에 관한 연구)

  • Jeon, Ho-Seok;Kim, Joon-soo;Moon, Young-bae;Lee, Jae-Jang
    • Journal of Industrial Technology
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    • v.21 no.A
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    • pp.257-261
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    • 2001
  • The separation of rare earths minerals is very difficult because of their similar chemical properties. The rare earth minerals are used as the mixed rare earth minerals or the misch metal without separation to each element. However, the high purity rare earths are recently produced commercially to each element so they there are used as the materials for high tech. Based on the characterization results for the raw minerals, we have developed a combined process containing gravity seperation, magnetic seperation and flotation. The result obtained from this study is monazite concentration of TREO grade 69.11% and Recovery 56.02%.

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A Study on Dobe Distribution at the Junction of $^{60}CO\;\gamma-Ray$ and Elecron Beam in Postoperative Radiotherapy of Breast Cancer (유암수술후 방사선치료시 $^{60}Co\;\gamma$선과 전자선 조사야 접합부 선량분포에 관한 연구)

  • Kang, Wee-Saing;Huh, Seung-Jae;Ha, Sung-Whan
    • Radiation Oncology Journal
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    • v.2 no.1
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    • pp.149-153
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    • 1984
  • Postoperative radiotherapy of breast cancer makes it possible to reduce loco-regional recurrence of breast cancer. The treatment technique, which can reduce the low-dose region at the junction and lung, is required. To produce proper dose distribution of internal mammary chain and chest wall, authors tried to find the method to expose $^{60}Co\;\gamma-ray$ on internal mammary region and 7MeV electron on chest wall. Exposure time of $^{60}Co\;\gamma$ and monitor unit of 9MeV were selected so that dose of $^{60}Co$ at 4cm depth was the same as that of 7Mev electron at $80\%$ dose depth. The position and direction of electron beam were changed for $^{60}Co$ beam: $0^{\circ},\;5^{\circ}$ for 0cm seperation; $0^{\circ},\;5^{\circ},\;10^{\circ}$ for 0.5cm seperation; $5^{\circ},\;10^{\circ},\;15^{\circ}$ for 1cm seperation. The results are as followings. 1. When the seperation of two fields was increased, dose on the axis of $^{60}Co$ beam was increased and dose at the junction region decreased while the volume of lung to be exposed to high dose and hot spot size were irregularly changed. 2. The dose distribution in the target volume of internal mammary and chest wall was most ideal when the seperation of two fields was $0\~0.5cm$ and the direction of electron beam was parallel to $^{60}Co$ beam.

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Structural Seperation of Unsymmetric Highrise Apartments (비정형 고층아파트에서의 구조체 분리 간격)

  • 정하선;현창국;윤영호
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1989.04a
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    • pp.56-60
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    • 1989
  • It is well known that the symmetric buildings have higher resistance than the unaymetric ones do under seismic load. However, it is sometimes inevitable to build an unsymmetric structure due to the site conditions or architectural needs. The unsymmetric building has structural disadvantages under seismic load. In such a case the structural seperation joints are often used to avoid those disadvantages. This paper presents a method to determine the width of the seperation joints for unsymmetric, reinforced concrete apartments structured by walls and slabs only. The variables of the study were the ratio of shear-wall stiffness to the building length in the same directron, the building height and the story mass.

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A Case of Child Seperation Anxiety Disorder with Severe Weight Loss and School Refusal (심한 체중감소 및 등교거부증을 보인 분리불안장애 아동 1례)

  • Jang, Sang-Ruyl;Park, Hyung-Bae
    • Journal of Yeungnam Medical Science
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    • v.10 no.1
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    • pp.226-236
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    • 1993
  • Seperation anxiety disorder(SAD) is characterized by excessive anxiety about being apart from the individuals to whom a child is most attached. We noticed a case of a 13 year old boy's SAD with symptoms of nausea/vomiting, stomachache, school refusal, and severe weight loss. His mother was overanxious and overdependent but her dependency was frustrated due to family problem. We investigated this case from a point of developmental aspect and family dynamics and tried to attempt therapeutic approach.

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Rapid Method for Seperation and Quantitation of p-Nitrophenol Derivative by HPLC (p-Nitrophenol 유도체의 HPLC에 의한 신속 분리 정량)

  • 이완구
    • Journal of Environmental Health Sciences
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    • v.9 no.1
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    • pp.89-93
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    • 1983
  • Various analytical methods for p-Nitrophenol derivatives have been reported as follows. 1) Thin-Layer Chromatography, 2) Gas Chromatography, 3) Cholinesterase Activity Determination, 4) Diazo Method, 5) Nitrophenol Method, 6) Indophenol Method. But these methods are mainly analyse total quantity of p-Nitrophenol and are not available for the seperation and pose some analytical problems associated with extensive clean up procedure. A rapid and simple method was developed for the seperation and quantitation for the p-Nitrophenol and it's derivatives by HPLC. Also an experiment was undertaken by the authors for the quantitation of the p-Nitrophenol in the blood of the intoxicated body. Levels of p-Nitrophenol ranging from approximately 0.10 to $1.69 \mu g/ml$ for Parathion and $3.44 \mu g/ml$ for EPN in each sample were measured with the average recovery of $95.5\pm0.52%$

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Why the Prescribing-Dispensing Services Are Not Separated in Korea\ulcorner -An Economic Approach- (의.약분업 왜 안 되나\ulcorner -경제학적 일고-)

  • 변재환
    • Health Policy and Management
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    • v.2 no.2
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    • pp.179-193
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    • 1992
  • This paper attempts to explain why the prescribing-dispensing services are not seperated in Korea. The main reason why physicians and pharmacists do not compromise, even though the two parties support the seperation policy in public, is contended to be that both parties would lose their interests if the policy were implemented. Physicians' loss from giving up their vested rights to dispensing would be larger than their gain from an increase in the number of prescriptions. Pharmacists' loww from being forced not to to sell medicines without prescriptions would also be larger than their gain from prohibiting physicians from dispensing. The net ganier form the seperation policy would be the patients. Therefore, the seperation policy would not be implemented unless political pressure from general public surpasses that from physicians and pharmacists.

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Vibration Analysis of Arbitrarily-Shaped Beams (임의 형태를 가진 보의 진동해석)

  • 민경원;강경수;홍성목
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1993.10a
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    • pp.175-180
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    • 1993
  • A new method for the vibration analysis of arbitrarily-shaped beams is proposed on the assumption of imaginary seperation of the beams into prismatic beams and the remaining portions. The stiffness and mass of the beams are devided into two portions according to the seperation. Applying the mode shapes of prismatic beams and Lagrange's equations give new characteristics equation. This equation has a low dimension of matrix with the coupling terms showing the effect of remaining portions on the vibration of arbitrarily-shaped beams

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Effect of heat pump performance improvement by use of thermal tank with temperature seperation plate (격판분리 축열조의 히트펌프 성능개선 효과)

  • Moon, Jongpil;Lee, Sunghyoun;Kwon, Jinkyung;Kang, YounKoo;Lee, Sujang
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.80.1-80.1
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    • 2011
  • This study was carried out in order to estimate the effect of heat pump performance by use of thermal tank with 3 seperation plates which were able to divide thermal tank into 3 chambers that have different temperatures levels. For testing the effect of developed thermal tank which was installed for supplying the heat to the paprika greenhouse in Jinju city. The volume of thermal storage tank was designed for $110m^3$ which was able to cover 30% of heating capacity. The temperature difference was 3 degree Celcius between high temperature and low temperature when only heating circulation was made from heat pump to thermal tank. but 5.5 degree Celcius difference was made when heating circulation of heat pump to thermal thank and hot water supplying circulation of thermal tank to greenhouse was done simultaneously. As a result of this study showed that COP of heat pump was increased by 15% or more than that of using normal thermal tank because heat pump was able to take 3 ~ 5 degree Celcius lower thermal thank water constantly.

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