• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.432-432
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• 2005

사용후핵연료시료 중에 함유된 요오드(I-127 및 129)를 정량하기 위하여 화학적 방법으로 분리 회수하고 중성자방사화분석법을 이용하였다. 사전실험으로 모의사용후핵연료를 이용하여 회수율을 측정하였다. 모의 및 실제사용후핵연료시료를 $90^{\circ}C$에서 8 M $HNO_3$ 용액으로 용해하고 용해 후 용해용액 중의 잔류 요오드, 응축 및 휘발된 요오드 각각을 정량하였다. 응축 요오드는 핵연료 용해 후 재증류하여 회수하였다. 잔류 및 응축 요오드는 시료의 산화상태를 조절한 후 용매추출로 요오드를 회수한 다음 이온교환 또는 침전법으로 방사화학적으로 분리한 후 중성자방사화분석(RNAA)으로 정량하였다. 제작한 이온교환분리관 및 여과키트에 요오드를 흡착 또는 침전시켜 분리한 다음 중성자조사를 위한 삽입체(Insert)로 이용하였다. 휘발 요오드는 제조한 흡착체(Ag-silica gel)를 담은 흡착관에 포집하고 홉착체를 구간별 균질시료로 만든 다음 비파괴중성자 방사화분석(INAA)으로 정량하였다. 침전 및 흡착 요오드의 화학적 특성을 EPMA(electron probe microanalysis) 분석으로 조사하였다. 요오드 정량결과를 다른 방법으로 비교분석하기 위하여 음이온교환수지상에서 요오드를 정제 및 회수하기 위한 용리거동을 조사하였다.

• Economic and Environmental Geology
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• v.31 no.5
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• pp.375-388
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• 1998

The purpose of this study is to investigate the ore genesis and occurrence of the Wondong polymetallic mineral deposits. The Pb-Zn, Fe and W-Mo mineralizations are found in skarn zones which formed mainly in or along the fault shear zones with the $N25-40^{\circ}W$ and $N10-50^{\circ}E$ directions, whereas the Cu-Mo mineralization is appeared hydrothermal replacement zone. The skarn minerals consist mainly of garnet and epidote, which were the last alteration phases between pneumatolytic and hydrothermal stages. The mineral paragenesis toward the late stage are as follows: arsenopyrite, scheelite, magnetite, pyrite, pyrrhotite, sphalerite, galena, chalcopyrite and molybdenite. Average ore grades are 0.33 g/t Au, 46.29 g/t Ag, 0.06% Cu, 4.4% Pb, 2.61% Zn and 29.39% Fe in tunnels, and 0.31 % Cu, 0.52% Pb, 6.29% Zn, 29.29% Fe, 0.03% Mo and 0.12% $WO_3$ in drill cores. Fluid inclusion data shows that Type I (liquid-rich), Type II (vapor-rich) and Type III (halite-bearing) inclusions are coexisted and their homogenization temperatures are quite similar. This indicates that boiling conditions have been reached during the mineralization. It is also likely that the ore solutions were evolved through the mixing between magmatic and meteoric waters. Rhyolite and quartz porphyry far the mineralization probably are not responsible of the Wondong polymetallic mineral deposits.

• Journal of Welding and Joining
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• v.17 no.3
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• pp.90-95
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• 1999

The increase in high speed, multi-function and high I/O pin semiconductor devices highly demands high pin count, very thin, and high density packages. BGA is one of the solutions, but the package has demerits in package reliability, surface mounting problems due to the PCB warpage and solder joint crack related with TCE mismatch between the materials. On this study to verify the thermal fatigue lifetime of the solder joint FEM and experiments were performed after surface mounting BGA with different solder composition and reliability conditions. FEM showed optimum composition of Ag3.2-Sn96.5 and under the composition minimum creep deformation of the solder joint was calculated, and the thermal fatigue lifetime was improved. In view of temperature cycle condition, the conditions of $-65^{\circ}C$to $150^{\circ}C$ showed minimum lifetime and t was 1/3 of $0^{\circ}C$ to $125^{\circ}C$ condition. Test board was prepared and solder joint crack was verified. Until 1000cycle on soder joint crack was observed.

• Journal of the Korean Magnetics Society
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• v.10 no.6
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• pp.280-294
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• 2000

[(300nm)Ta/(500nm)NdFeB/(300nm)Ta] thin films were deposited at 5 mTorr Ag gas pressure by RF-DC magnetron sputtering, and their magnetic properties were investigated. The [Ta/NdFeB/Ta] films deposited on heated Si substrates showed high perpendicular anisotropy and excellent hard magnetic properties. The films sputtered at tile substrate temperature of T$\sub$s/=650$^{\circ}C$ and 700$^{\circ}C$ showed (BH)$\sub$max/=20 MGOe and $\sub$i/H$\sub$c/= 18.9 kOe along the perpendicular direction to the film plane, respectively.

• Journal of the Korean Electrochemical Society
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• v.5 no.4
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• pp.178-182
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• 2002

The electrochemical behavior of binder-free carbon anode, comprising of only artificial and natural graphite (AG and NG) particles, for intercalation and deintercalation of lithium ion $(Li^+)$ in aluminum chloride (AICI_3)-I-ethyl­3-methylimidazolium chloride (EMIC)-lithium chloride (LiCl)-thionyl chloride $(SOCI_2)$ room-temperature molten salt (RTMS) was studied. Binder-free carbon electrodes were fabricated using electrophoretic deposition (EPD) method. The binder-free carbon anodes provided a relatively flat charge and discharge potentials $(0\;to\;0.2V\;vs.\;Li/Li^+)$ and current capabilities $(250-340mAh{\cdot}g^{-1})$ for the intercalation and deintercalation of $Li^+$. Stability of the binder-free carbon anodes for intercalation and deintercalation of 50 cycles was confirmed.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.633-637
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• 2003

We have studied the surface-enhanced Raman spectroscopy (SERS) spectrum of quinomethionate (6-methyl-1,3-dithiolo[4,5-b]quinoxalin-2-one), which is an insecticide or fungicide used on vegetables and wheat. We observed no signals in the ordinary Raman spectra of solid-state quinomethionate, but when it was adsorbed on a colloidal silver surface, strong vibrational signals were obtained at a very low concentration. The SERS spectra were obtained by silver colloids prepared by the Creighton et al. method. The influence of pH and the aggregation inductors ($Cl^-,\;Br^-,\;I^-,\;F^-$) on the adsorption mechanism was investigated. Two different adsorption mechanisms were deduced, depending on the experimental conditions: The one N atom or two N atoms are chemisorbed on an Ag surface. An important contribution of the chemical mechanism was inferred when the one N atom was perpendicularly adsorbed on a surface. It is possible that quinomethionate can be detected to about $10^{-5}$ M.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.20.2-20.2
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• 2009

최근 무전해 식각법을 이용한 실리콘 나노와이어 합성이 다양한 각도에서 이루어지고 있다. 무전해 식각법을 통한 나노와이어 합성은, 단결정 실리콘 기판에 촉매를 올려 기판을 식각할 수 있는데, 이 방법을 이용하여 넓은 면적의 수직방향으로 배열된 10 ~ 300nm 지름의 단결정 실리콘 나노와이어를 합성할 수 있다. 본 연구에서는 무전해 식각법으로 boron이 도핑된 p-type실리콘 기판을 식각하여 실리콘 나노와이어를 합성하였고, 단일 나노와이어의 field-effect transistor(FET) 소자가 가지는 전기적 특성에 대하여 분석하였다. 특히 무전해 식각법을 이용하여 나노와이어를 합성할 때, 촉매로 사용되는 Ag particle이 나노와이어에 미치는 영향에 대해서 분석해 보았다. FET 소자의 게이트 절연막은 가장 일반적으로 사용되는 SiO2 (300nm)와 고유전체로 잘 알려진HfO2(80nm)를 사용하여 전기적 특성을 비교하여 보았다. 한편, HfO2 박막은 atomiclayer deposition(ALD)장비를 이용하여 증착하였다. 합성된 실리콘 나노와이어의 경우 X-ray diffraction(XRD)로 결정성을 확인하였으며, high-resolution transmission electron microscopy(HRTEM)으로 결정성 및 나노와이어의 표면 형태를 확인하였다. 전기적 특성은 I-V 측정을 통하여 Ion/Ioff ratio, 이동도, subthreshold swing, subthreshold voltage값을 평가하였다.

• Korean Journal of Microbiology
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• v.33 no.2
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• pp.97-104
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• 1997

Herpes simpex virus type 2 (HSV-2) infects the genital and oral mucosae of human and other animals. HSV-2 infection is a widespread health problem causing various clinical syndromes including oral, genital, and ocular lesions, viral encephalitis, and recurrent diseases. Hybridorna cell lines secreting a monoclonal antibody (mAb) against the HSV-2 were produced by fusing spleen cells of HSV-2-immunized mice with Sp2/0-AgI4 myeloma cells. One hybridoma cell line was established and its monoclonal C-2, IgM, recognized the antigens of 134, 86, and 43 kDa in western blot analysis. In SDS-P AGE analysis of HSV -2 antigens, 25 bands were separated between 3D kDa and 159 kDa. In indirect immunofluorescent assay, mAbs exhibited binding to the virus antigen expressed on Vero cell infected with HSV-2.

• Electrical & Electronic Materials
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• v.7 no.5
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• pp.389-396
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• 1994

The bilayer film of Ag/a-S $e_{75.G}$ $e_{25}$ and the monolayer film of a-S $e_{75.G}$ $e_{25}$ act as a negative-type and a positive-type resist in focused ion beam lithography, respectively. Using a model which takes into account the ion stopping power, the ion projected range, the ion concentration implanted into resists and the ion transmission coefficient, etc., the ion resist parameters are calculated for a broad range of ion energies and implanted doses. Ion sources of A $r^{+}$, S $i^{++}$ and G $a^{+}$ are used to expose resists. As the calculated results, the energy loss per unit distance by Ga'$^{+}$ ion is about 10$^{3}$[keV/.mu.M] and nearly constant for all energy range. Especially, the projected range and struggling for 80[keV] G $a^{+}$ ion energy are 0.0425[.mu.m] and 0.020[.mu.m], , respectively and the resist thickness of a-S $e_{75}$ G $e_{25}$ to minimize the ion penetration rate into a substrate is 0.118[.mu.m].u.m]..u.m].

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2016.09a
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• pp.41-43
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• 2016