• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.441-441
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• 2007

As Rhenium-Iridium{Re-Ir) coating possesses such features as, high hardness, high elasticity, abrasion resistance and chemical stability, there have been exerted continuous efforts in research works in a variety of fields, and this technology has also been applied widely to industrial areas. In this research, the optimal grinding condition was identified using Microlens Process Machine in order to contribute to the development of aspheric glass lens for mobile phone module having 3 mega pixel and 2.5X zoom, and molding core(WC) was manufactured having performed ultra-precision machining. Effects of Re-Ir coating on form accuracy (P-V) of molding core and surface roughness(Ra) were measured and evaluated.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1999년도 제38차 추계학술대회
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• pp.13.2-13.2
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• 1999

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2000년도 특별강연 및 춘계학술발표대회 개요집
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• pp.211-214
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• 2000

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2002년도 추계학술발표회요약집
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• pp.382.1-382
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• 2002

• 한국재료학회지
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• 제10권5호
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• pp.335-342
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• 2000

리늄판의 미세경도를 압흔 하중 및 온도의 함수로 구하였다. 미세경도의 온도의존성은 상온에서 100$0^{\circ}C$까지의 범위에서 Vickers 압흔기가 내장된 고온 미세압흔기를 이용하여 연구되었다. 미세경도의 하중의존성은 Vickers와 Knoop 압흔기를 이용하여 검토되었다. 압흔 크기 영향은 표준화된 Meyers법칙에 위해 충분히 설명 되었다. 압흔도중 압흔기 아래에서의 가공경화 때문에 어닐링된 리늄판 경도값은 높은 압흔 하중에서 압련되 리늄판의 경도값에 접근하였다. 경도의 하중의존성으로부터 외삽하여 얻어진 하중 영에서의 경도값은 경도값이 다른 열활성을 나타내는 두 개의 다른 기구에 의해 제어됨을 제시하였다. 낮은 온도에서 활성화에너지는 0.02eV 였으며, 한편 높은 온도에서 활성화에너지는 0.15eV 였다. 이때 전이온도는 대략 $250^{\circ}C$ 이었다.

• 한국재료학회지
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• 제26권12호
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• pp.751-756
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• 2016

Graphite was diffusion-bonded by hot-pressing to W-25Re alloy using a Ti interlayer. For the joining, a uniaxial pressure of 25 MPa was applied at $1600^{\circ}C$ for 2 hrs in an argon atmosphere with a heating rate of $10^{\circ}C\;min^{-1}$. The interfacial microstructure and elemental distribution of the W-25Re/Ti/Graphite joints were analyzed by scanning electron microscopy (SEM). Hot-pressed joints appeared to form a stable interlayer without any micro-cracking, pores, or defects. To investigate the high-temperature stability of the W-25Re/Ti/Graphite joint, an oxy-acetylene torch test was conducted for 30 seconds with oxygen and acetylene at a 1.3:1 ratio. Cross-sectional analysis of the joint was performed to compare the thickness of the oxide layer and its chemical composition. The thickness of W-25Re changed from 250 to $20{\mu}m$. In the elemental analysis, a high fraction of rhenium was detected at the surface oxidation layer of W-25Re, while the W-25Re matrix was found to maintain the initial weight ratio. Tungsten was first reacted with oxygen at a torch temperature over $2500^{\circ}C$ to form a tungsten oxide layer on the surface of W-25Re. Then, the remaining rhenium was subsequently reacted with oxygen to form rhenium oxide. The interfacial microstructure of the Ti-containing interlayer was stable after the torch test at a temperature over $2500^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• 제16권10호
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• pp.1491-1498
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• 2006

The feasibility of pullulan acetate nanoparticles (PAN) with ionic strength (IS) sensitivity as a radioisotope carrier to inhibit tumor growth is demonstrated. PAN was radiolabeled with rhenium 188 (Re-188) without any chelating agents. The labeling efficiency of Re-188 into PAN (Re-188PAN) was $49.3{\pm}4.0%$ as determined by TLC. The tumor volumes of mice treated with 0.45 mCi of Re-188-PAN were measured and compared with that of free Re-188 after 5 days of intratumoral injection. For the histological evaluation of apoptotic nuclei of tumor cells, hematoxylin and eosin (H&E), and terminal deoxynucleotidyl transferase biotinylated deoxyuridine triphosphate nick end labeling (TUNEL) staining were performed. The mean tumor volume of the Re-188-PAN-treated group was decreased by 36% after 5 days, whereas that the free Re-188-treated group was decreased by only 15% (P<0.05). The mean number of TUNEL-positive cells in Re-188-PAN-treated tumors at $144.3{\pm}79.9$ cells/section was significantly greater than the control ($26.7{\pm}7.9$ cells/section, P=0.03). The numbers of leukocyte and lymphocyte were decreased in both free Re-188- and Re-188-PAN-treated mice. These results indicated that the intratumoral injection of Re-188-PAN effectively inhibits the tumor growth by prolonging Re-188 retention time in tumor site induced by the IS sensitivity.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2007년도 춘계학술대회 논문집
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• pp.17-18
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• 2007

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2005년도 춘계학술발표회
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• pp.313-314
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• 2005

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1999년도 추계학술발표회요약집
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• pp.335-335
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• 1999