• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.4-4
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• 1997

• Proceedings of the Korean Magnestics Society Conference
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• 1996.05a
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• pp.52-53
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• 1996

• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.43-43
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• 2006

• Proceedings of the Korean Vacuum Society Conference
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• 2002.02a
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• pp.208-208
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• 2002

• Proceedings of the Membrane Society of Korea Conference
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• 2000.04a
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• pp.59-62
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• 2000

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.585-588
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• 1998

We investigated the ultra-low energy B, P, and As ion implantation using ungraded MDRANGE code to form nanometer junction depths. Even at the ultra-low energies that were simulated in paper, it was found that channeling cases must be carefully considered. In the cases of B, channeling occurred above 500 eV, in the cases of P, channeling occurred above 1 keV, and in the cases of As, channeling occurred above 2 keV. Comparing 2D dopant profiles of 1 keV B, 2 keV P, and 5 keV As with tilts, we demonstrated that most channeling cases occurred not lateral directions but depth directions. Through thus results, even below 5 keV energy ion implant considered here, it is estimated that channeling effects are important in the formation of nanometer junction depths.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04a
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• pp.55-56
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• 2009

A light guiding plate (LGP) with nanometer-sized patterns was fabricated by injection molding method which employed electrically healed mold and the transcription of injection-molded parts was investigated. A Ni stamper was fabricated using MEMS technology. The Ni stamper was then installed in a movable heated core which is a key part of the mold. Using this mold, injection-molded plastic LGP parts were manufactured at different mold temperatures and the effect of the temperature on the transcription of the parts was investigated.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.1932-1936
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• 2008

A new analytical method using 1-(2-pyridylazo)-2-naphthol modified $SiO_2$ nanoparticles as solid-phase extractant has been developed for the preconcentration of trace amounts of mercury(II) in different water samples. Conditions of the analysis such as preconcentration time, effect of pH, sample volumes, shaking time, elution conditions and effects of interfering ions for the recovery of analyte were investigated. The adsorption capacity of nanometer $SiO_2$-PAN was found to be 260 ${\mu}molg^{-1}$ at optimum pH and the detection limit (3$\sigma$) was 0.48 ${\mu}gL^{-1}$. The extractant showed rapid kinetic sorption. The adsorption equilibrium of mercury(II) on nanometer $SiO_2$-PAN was achieved just in 5 mins. Adsorbed mercury(II) was easily eluted with 5 mL of 6 M hydrochloric acid. The maximum preconcentration factor was 50. The method was applied for the determination of trace amounts of mercury(II) in various water samples and industrial effluents.

• Journal of the Korean Ceramic Society
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• v.47 no.2
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• pp.177-182
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• 2010

To synthesize $Gd_2O_3:Eu^{3+}$ phosphor, gadolinium-europium oxalate precursors were prepared from oxalic acid, NaOH or aqueous ammonia via coprecipitation method. The obtained precursors were heat-treated and then characterized by XRD, SEM and PL. The kinds and amounts of coprecipitant (NaOH or aqueous ammonia) were found to affect the powder morphology and properties of gadolinium-europium oxalate precursors. Two crystalline precursors and one amorphous precursor were synthesized. The nanometer-sized amorphous gadolinium-europium oxalate precursor was first prepared using the oxalate coprecipitation technique. The calcined powders obtained from the amorphous precursor were nearly spherical in shape, and a narrow size distribution was obtained. The NaOH coprecipitant was more effective in the preparation of nanometer-sized spherical powders. A thermal decomposition process was conducted for the three kinds of precursors. The photoluminescence property was also measured as a function of europium content, and concentration quenching occurred for samples with europium concentrations of over 10 mol%.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1334-1336
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• 2001

In this study, laser ablation atomic fluorescence (LAAF) spectroscopy has been applied for a nanometer-scale surface analysis of Na-doped polymethyl methacrylate (PMMA). LAAF spectroscopy is a new sensitive element detection technique which involves atomizing of a sample by the laser ablation and detection of ablated plume by laser-induced fluorescence (LIF) spectroscopy. Using this technique in the detection of Na atoms with Na-doped PMMA, a detection limit is obtained as 36 fg for single laser shot. Further, the depth distribution in the sample is measured with a very high spatial resolution using a two-layer PMMA sample by observing the shot-by-shot LIF intensity from the Na atoms.