• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1239-1240
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• 2006

Effects of $Ag_2O$ doping on the electromagnetic properties in the BiSrCaCuO superconductors. The electromagnetic properties of $Ag_2O$ doped and undoped BiSrCaCuO superconductor were evaluated to investigate the contribution of the pinning centers to the magnetic effect. It was confirmed experimentally that a large amount of magnetic flux was trapped in the $Ag_2O$ doped sample than that in the undoped one, indicating that the pinning centers of magnetic flux are related closely to the occurrence of the magnetic effect. It is considered that the area where normal conduction takes place increases by adding $Ag_2O$ and the magnetic flux penetrating through the sample increases. The results suggested that Ag acts to increase pinning centers of magnetic flux, contributing to the occurrence of the electromagnetic properties.

• Journal of Electrical Engineering and Technology
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• 제2권1호
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• pp.102-105
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• 2007

Effects of $Ag_2O$ doping on the electromagnetic properties in the BiSrCaCuO superconductors. The electromagnetic properties of the $Ag_2O$ doped and undoped BiSrCaCuO superconductor were evaluated to investigate the contribution of the pinning centers to the magnetic effect. It was confirmed experimentally that a large amount of magnetic flux was trapped in the $Ag_2O$ doped sample than that in the undoped one, indicating that the pinning centers of magnetic flux are related closely to the occurrence of the magnetic effect. It is considered that the area where normal conduction takes place increases by adding $Ag_2O$ and the magnetic flux penetrating through the sample increases. The results suggested that Ag acts to increase the pinning centers of the magnetic flux, contributing to the occurrence of the electromagnetic properties.

• Journal of Electrochemical Science and Technology
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• 제11권4호
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• pp.392-398
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• 2020

Producing solar grade silicon using an inexpensive method is a key factor in lowering silicon solar cell costs; the direct electrochemical reduction of SiO₂ in molten salt is one of the more promising candidates for manufacturing this silicon. In this study, SiO₂ granules were electrochemically reduced in molten CaCl₂ (850℃) using Ag-Si eutectic droplets that catalyze electrochemical reduction and purify the Si product. When Ag is used as the working electrode, the Ag-Si eutectic mixture is formed naturally during SiO₂ reduction. However, since the Ag-Si eutectic droplets are liquid at 850℃, they are easily lost during the reduction process. To minimize the loss of liquid Ag-Si eutectic droplets, a cylindrical graphite container working electrode was introduced and Ag was added separately to the working electrode along with the SiO₂ granules. The graphite container working electrode successfully prevented the loss of the Ag-Si eutectic droplets during reduction. As a result, the Ag-Si eutectic droplets acted as stable catalysts for the electrochemical reduction of SiO₂, thereby producing one-dimensional Si rods through a mechanism similar to that of vapor-liquid-solid growth.

• 공업화학
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• 제16권1호
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• pp.123-130
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• 2005

산소 PSA용 흡착제의 제조를 위하여 표면적이 큰 제올라이트 X형 흡착제를 합성하고 양이온교환을 통하여 질소의 선택적 흡착 능력이 우수한 흡착제로 제조하였다. 제올라이트 X형 흡착제는 50 L급 대형 반응기에서 $SiO_2\;:\;Na_2O\;:\;H_2O\;:\;Al_2O_3$ = 2.5 : 3.5 : 150 : 1의 조성으로 $98^{\circ}C$, 18 h 동안 반응한 결과 표면적이 $650m^2/g$ 이상의 표면적을 나타내었다. 흡착제의 양이온교환은 Li, Ag, Ca, Br, Sr 등의 금속 이온을 대상으로 조사하였다. Ag 이온의 이온교환 속도가 가장 빠르게 일어났으며 모든 금속 이온이 제올라이트 X형에 포함된 Na 이온과 거의 당량적으로 이온 교환이 일어남을 알 수 있었다. 양이온 교환된 제올라이트 X형 흡착제의 질소와 산소의 흡착 성능을 $10{\sim}40^{\circ}C$, 0~9 atm의 범위에서 측정한 결과 이온교환을 하지 않은 NaX 흡착제에 비하여 월등히 높은 흡착 성능을 나타내었으며 이온 교환된 제올라이트 X형 흡착제의 질소 흡착량은 0.5 atm 이하의 저압에서는 Ag > Li > Ca > Sr > Ba > K 이온의 순으로 나타났으나 1 atm 이상의 고압에서는 Li > Ag > Ca > Sr > Ba > K 이온의 순으로 나타났다. 공기의 조성에 준하는 질소 및 산소의 분압에서 흡착량의 비를 조사하여 질소/산소 분리도를 측정한 결과 $20^{\circ}C$의 온도에서 Li으로 이온 교환된 흡착제의 분리도는 13.023을 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.101-103
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• 2001

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing Ag$_2$O It has been cleared that Ag$_2$O acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.69-70
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• 2002

Suspension effect has been studied by using superconductor of BiPbSrCaCuO ceramics containing $Ag_2O$. It has been cleared that $Ag_2O$ acts as pinning center which plays an important role to the suspension effect. Magnetic repulsive force which affects a superconductor located in magnetic flux from toroidal magnet has been investigated. It has been concluded that the suspension effect arises from the interaction between the pinning effect and the diamagnetic effect.

• 분석과학
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• 제11권4호
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• pp.248-253
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• 1998

수용액에서 poly-dibenzo-18-crown-6를 이용한 알칼리, 알칼리토금속이온 및 전이금속이온들의 흡착 및 분리특성을 조사하였다. 알칼리금속이온들과 알칼리토금속이온들의 흡착정도와 분포비의 순위는 각각 Li(I)

• Journal of Magnetics
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• 제17권3호
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• pp.176-184
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• 2012

The structural, magnetic and magnetotransport properties of $La_{0.67}Ca_{0.33}MnO_3$: $Ag_x$ (x = 0, 0.1, 0.2, 0.3 and 0.4) composites were investigated systematically. X-ray and EDX analysis indicated that Ag is not substituted into the main $La_{0.67}Ca_{0.33}MnO_3$ phase and remains an additive to the second phase at the grain boundary. The Curie temperature first decreased from 269 K for x = 0 to 257 K for x = 0.1 and then remained nearly unchanged with increasing Ag content. For the x > 0.1 samples, a second transition temperature ($T_{MI2}$) was observed in the resistance curves. At temperatures below 150 K, a significant enhancement in MR was observed while high temperature MR decreased with increasing Ag content. The maximum MR was observed to be 55% in the x = 0.4 sample at 10 K and a 6T magnetic field, this value is larger than that of pure $La_{0.67}Ca_{0.33}MnO_3$ (53% at 265 K and 6 T). In addition, at low fields (H < 1T), a sharp increase in the MR was observed.

• 한국산학기술학회논문지
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• 제2권2호
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• pp.91-94
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• 2001

Glass ceramics composed of (5-X)$Li_2O$ㆍ$XAg_2O$ㆍ36CaOㆍ$20TiO_2$.27$P_2O_5$(X=1 to 5) were prepared by melting process and 2 step heat treatment for nucleation at$610^{\circ}C$ and crystallization at $730^{\circ}C$, Fabricated crystal phases were $LiTi_2(PO_4)_3$(LTP),$AgTi_2(PO_4)_3$(AgTP)와 $\beta-Ca_3(PO_4)$. Antibacterial effects and characterizations of the glass ceramics as $Ag_2$O content were investigated. Staphylococcus aureus and Salmonella typhi were used in this study. Staphylococcus aureus and Salmonella typhi bacteria were removed 5 hours added after glass ceramics.

• 한국균학회지
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• 제20권1호
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• pp.44-50
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• 1992

Rhizoctonia solani의 균사융합군(AG) 중에서 생장속도가 빠른 AG-1과 AG-4는 가장 많은 원형질체를 형성하였으며 속도가 느린 AG-3은 저조하였고 중간인 AG-2와 AG-5는 또한 중간이었다. 균핵의 형성은 AG에 따라 차이가 있었다. Cellulase "onozuka" R-l0, macerozyme R-10, ${\beta}-glucuronidase$의 효소 복합액에서 가장 많은 원형질체를 형성하였다. 5개 융합군은 30시간 배양한 3g의 균사를 0.6 M mannitol이 첨가된 효소 복합액에 $32^{\circ}C$에서 3-4시간 처리하면 가장 많은 원형질체를 형성하였다. 균핵을 형성하는 AG-1을 열처리로 불활성화시킨 후 균핵을 형성하지 않는 AG-5의 원형질체를 PEG와 ${Ca}^{2+}$로 융합시켰다. 재생배지상에서의 균총의 특징과 균핵의 형성에 의해 7 개의 원형질 융합체를 선발하고 esterase 동위효소의 zymogram 및 AG-1 과 융합체인 F150l 사이에서 일어나는 killing reaction으로 확인하였다.