• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2092-2094
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• 2000

As a next generation lithography (NGL) technology for VLSI semiconductor fabrication, electron beam, ion beam, X-ray and extreme ultraviolet(EUV) are considered as possible candidates. Among these methods, EUV lithography(EUVL) is thought to be the most probable because it is easily realized by improving current optical lithography technology. In order to set EUV radiation which can be applied to EUVL, it is essential to generate very high density and high temperature plasma stably. The method using a pulse power laser and a high voltage pulse discharge is commonly used to accomplish such a high density and high temperature plasma. In this paper we review the recent trends of the EUV generation technique by high density and high temperature plasma.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1255-1260
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• 2004

Decomposition of ozone at room temperature was investigated comparatively with commercial monolithic ozone decomposition catalyst (ODC, $MnO_2$) and monolithic photo catalyst ($TiO_2$). The effects of residence time, UV (ultraviolet) light dependence and ozone concentration on the conversion was presented. UV ray was irradiated using BLB (black light blue) lamp ($315{\sim}400$ nm), supplied with a constant intensity in the reactor. The concentration of ozone in the square-shape reactor can be controlled by combining the DBD (dielectric barrier discharge) reactor with an AC high voltage supply system. The catalytic performance, in presence of UV irradiation did not show significant changes for $MnO_2$ catalyst. $TiO_2$ catalyst was the different case, which showed higher decomposition activity in presence of UV irradiation. Deactivation of catalyst detected by real-time ozone monitor for 120 hours with a constant inlet ozone concentration.

• Journal of Applied Reliability
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• v.5 no.4
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• pp.405-412
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• 2005

In this paper, we verified the failure mechanism of the discolored masking tape wrapped around the wire and studied an improved case study as well. Masking tapes are poly(Vinylchloride-co-Methyl methacrylate) (PVC) and the wire connecting with indoor/outdoor components of the air conditioner is chloroprene(CR). The masking tape under. the ultraviolet ray was accelerated to discolor fivefold. The results determined reveal the discoloration of masking tapes as an elution of the additives, dephenyl Amine series antioxidants, in the connecting wire. When changed dephenyl Amine series to phenol series, we found that the degree of discoloration was dramatically decreased. Due to stink of Thiourea and Thiuram monosulfide, as accelerators in CR wire, we controlled the vulcanization temperature and time without using these accelerators and could get the wire not to smell bad with the equal mechanical properties.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2669-2674
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• 2009

Controlled reduction of silver alkylcarbamate complexes with hydrogen gas was investigated as a facile synthetic method for high concentrations of silver nanocolloids in organic solvent. Polyvinylpyrrolidone (PVP) was used to stabilize the silver colloids obtained from the chemical reduction. To determine optimum conditions for preparation of the stable and controlled silver colloids with the narrowest particle size and distribution, a large number of experiments were carried out involving variations in the concentrations of the silver 2-ethylhexylcarbamate (Ag-EHCB) complex, PVP, and 2-propanol. The initial colloid had a mean particle diameter between 5$\sim$50 nm, as measured by transmission electron microscopy, and exhibited a sharp absorption band in the UV region with a maximum size near 420 nm. After treatment with a reducing agent, the colloids were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.131.1-131.1
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• 2012

We use three-dimensional magnetohydrodynamic (MHD) simulations of flux emergence from solar subsurface to corona. In our previous work, we reported the relation between magnetic-field configuration and the flux expansion factor. Following these results, we investigate where an upflow is generated in an active region and how its location is related to the flux expansion factor. We also derive physical quantities of a real active region from observation data provided by Nobeyama Radioheliograph (NoRH), X-Ray Telescope (XRT), and Extreme Ultraviolet Imaging Spectrometer (EIS) onboard Hinode. These physical quantities are plasma density, temperature and flow. By comparing the simulation result and observational one, we will discuss the properties of the location producing a solar wind.

• Elastomers and Composites
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• v.55 no.3
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• pp.191-198
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• 2020

Nickel oxide (NiO) nanoparticles were synthesized by a reaction of nickel nitrate hexahydrate (Ni(NO₃)₂·6H₂O) and sodium hydroxide (NaOH). The synthesized NiO nanoparticles were examined with X-ray diffraction, scanning electron microscopy, Raman spectroscopy, and ultraviolet-visible (UV-vis) spectroscopy. The NiO nanoparticles were used as the catalyst for the reduction of o- and m-nitroaniline to phenylenediamine. The reduction rate of m-nitroaniline was faster than that of o-nitroaniline. The reduction rate for both o- and m-nitroaniline increased as the reaction temperature increased. The rate of reduction for nitroaniline followed a pseudo first-order reaction rate law.

• Applied Science and Convergence Technology
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• v.23 no.5
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• pp.301-307
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• 2014

We have fabricated $SnO_2$/Zn core-shell nanowires by employing a sputtering technique with a Zn target. Scanning electron microscopy indicated that the surface of the nanowires became rougher by the coating. X-ray diffraction of the coated nanowires exhibited the hexagonal Zn diffraction peaks. TEM image of coated structures showed that shell layer was mainly comprised of hexagonal Zn phase. EDX spectra suggested that the shell layer consisted of Zn elements. The photoluminescence spectrum of the coated nanowires in conjunction with Gaussian fitting analysis revealed that the emission was disconvoluted with three Gaussian functions, which are centered at 2.1 eV in the yellow region, 2.4 eV in the green region, and 3.3 eV in the ultraviolet region. We speculated the possible mechanisms of these emission peaks.

• Journal of Pharmaceutical Investigation
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• v.18 no.4
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• pp.181-186
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• 1988

Inclusion complex of sulfamethoxazole with ${\beta}-cyclodextrin$ was prepared by freeze-drying method in molar ratios of 1:1, 1:1.25, 1:1.5 and 1:1.75, and the complex formation was identified by ultraviolet and infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Dissolution rate and solid state stability of the complex were investigated in comparison with those of sulfamethoxazole powder and the physical mixture of sulfamethoxazole with ${\beta}-cyclodextrin$. As a result, the dissolution rate and the stability of solid complexes in various relative humidity conditions increased more remarkably than those of sulfamethoxazole powder and physical mixture. But the difference according to molar ratio of the complex was not recognized.

• Corrosion Science and Technology
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• v.20 no.4
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• pp.169-174
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• 2021

In this study, performance tests, a field evaluation, and a life cycle cost (LCC) analysis for high performance coating systems were conducted to prepare a plan to reduce the cost of maintenance coating and contribute to the service life extension of steel bridges by applying high performance coatings to steel bridges that will be constructed in the future. From the deterioration models based on the field evaluation for chlorinated rubber and urethane topcoat systems, which have been applied often, the mean service lives were derived as 20.8 and 26.6 years, respectively. For the other coating systems that have not been applied in practice, the coordination factors were differentially applied with evaluation items. The most durable coating system was predicted to be thermal spray coating (TSC) primer/epoxy intermediate coat/fluoride resin topcoat, with a predicted value as long as 42.2 years. The LCC analysis indicates that partial application of high performance coating, such as TSC and fluoride resin, to specific parts vulnerable to corrosion and ultraviolet ray (UV) is more advantageous than the use of general coating systems.

• Elastomers and Composites
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• v.54 no.3
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• pp.252-256
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• 2019

Fullerene oxide[$C_{60}(O)_n$, ($n{\geq}1$)] was synthesized by dissolving fullerene[$C_{60}$] and 3-chloroperoxybenzoic acid in toluene under refluxing condition for 5 h. Hybrid fullerene oxide-silver nanoparticle composites were synthesized by dissolving fullerene oxide and silver nitrate[$AgNO_3$] in diethylene glycol under ultrasonic irradiation for 3 h. The synthesized hybrid nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, and ultraviolet-visible[UV-vis] spectroscopy. The catalytic activity for the reduction of various nitroanilines[NAs] was identified by UV-vis spectrophotometer. The efficiency of the catalytic reduction by the synthesized hybrid nanocomposites has an order of 4-NA > 2-NA > 3-NA.