• Korean Journal of Materials Research
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• v.12 no.11
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• pp.870-874
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• 2002

$Mg_2$$SiO_4$: Dy, Tb pellets were made by using a sintering process, including pressing and heat treatment. In the present study, the optimum parameters of the sintering for the $Mg_2$$SiO_4$: Dy, Tb pellets obtained such as the pressing pressure, the sintering temperature and the sintering time were in terms of thermoluminescence. Experimental results showed that the main peak of the glow curve for $Mg_2$$SiO_4$: Dy, Tb thermoluminescence dosimeter was clearly correlated with the energy of the UV and with the grain size. The intensity of the TL glow curve increased and its main peak position shifted to lower temperature with increasing UV irradiation time.

• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.448-454
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• 1996

This studies was carried out to know the effects of $ultraviolet-B(280{\sim}320nm)$ irradiation on the initial growth of Tilia amurensis Rupr. seedlings. UV-B irradiation inhibited the hypocotyl elongation, height growth, leaf growth, and chlorophyll formation. The inhibition was dose-dependent, and consequently those growths were more inhibited depending on the increase of UV-B levels. Morphological change such as leaf length/leaf width ratio was also observed in the leaves of irradiated seedlings. UV-B irradiation produced scorching, glazing or chlorosis, and stunting or dwarfing in the first or second leaf of the seedlings.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.2
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• pp.195-201
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• 2007

A submerged flat-sheet membrane separation system integrated with PAC (powdered activated carbon) was used in this research in order to investigate the effects of PAC on the efficiencies of operation and treatment and to evaluate the performance of the system. The experiments were carried out under operating conditions of a filtration rate of 0.38 m/d, water temperature of $20-28^{\circ}C$, and PAC dose of 0 g/L (Run-A) and 20 g/L (Run-B). The influent concentrations of TOC (total organic carbon), $NH_4{^+}-N$ (ammonia nitrogen) and $UV_{254}$ (UV absorbance at 254 nm) were 2.48 mg/L, 1.4 mg/L and 2.53 1/m, respectively. TOC removal of 43.2 and 73.6%, ammonia nitrogen removal of 4.9 and 15.9%, and $UV_{254}$ removal of 20.6 and 31.6% were obtained for Run-A and Run-B, respectively. During an experimental period of 33 days, no change was found in TMP (Run-B), but the TMP in Run-A increased by 5 kPa after 29 days. This research showed that the filtrate quality and the performance efficiency were enhanced when PAC was introduced into the filtration system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.367-370
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• 2003

In this study, application of SAM (self-assembled monolayer) to nano replication process as an anti-adhesion layer was presented to reduce the surface energy between the nano mold and the replicated polymeric nano patterns. The electron beam lithography was used for master nano patterns and the electorforming process was used to fabricate the nickel nano stamper. Alkanethiol SAM as an anti-adhesion layer was deposited on metallic nano stamper using solution deposition method. To analyze wettability and adhesion force of SAM, contact angle and LFM (Lateral Force Microscopy) were measured at the actual processing temperature and pressure for the case of nano compression molding and at the actual UV dose for the case of nano UV molding. It was found that the surface energy due to SAM deposition on the nickel nano stamper markedly decreased and the quality of SAM on the nickel stamper maintained under the actual molding environments.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.420.2-421
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• 2002

A validated UV determination of loratadine in human plasma was developed and the pharmacokinetic profiles of single dose of loratadine were determined in 8 healthy volunteers. Human serum samples (1.0 mL) spiked with known concentration of loratadine and 50 ng diazepam as an internal standard were alkalinized with 500 ${\mu}\ell$ ${\mu}\ell$ of 10% $Na_{2}CO_{3}$ and extracted with 7 mL of mixture of isopentane and hexane (2 : 1. v/v) for 5 min. Extracts were centrifuged and 6 mL of organic layer was back-extracted with 150 ${\mu}\ell$ of 12.5% $Na_{2}PO_{4}$ for 1 min. (omitted)

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.197-198
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• 2000

A surface-assisted photo-control of the liquid crystal (LC) alignment has been achieved by modifying the topmost surface of the polyimide film with photo-reactive molecules. Recently, photo-alignment technique using a thin film of poly(vinyl cinnamates) have been reported. However their commercial potentiality is limited by their low thermal stability. To enhance thermal stability, we synthesized the chalcone derivatives as the photo-reactive molecules and introduced the materials on the surface-modified polyimide film.. We identified that the photo-chemical reaction of the chalcone derivatives occur in few minutes with irradiation of UV light. The photo-alignment characteristics of the modified polyimide films treated by polarized UV light and their LC cells are investigated as a function of exposure dose.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.53 no.7
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• pp.382-386
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• 2004

A study has been made of surface modification of organic materials by ion implantation to increase the surface electrical properties. The substrate used were PET(polyethylene teraphtalate). N$^{＋}$, Ar$^{＋}$ implantation was peformed at energies of 40 keV and 50 keV with fluences from $5{\times}10^{15}$, $1{\times}10^{16}$,$7{\times}10^{16}$, $1{\times}10^{17}$/ ions/$cm^2$. UV/Vis, FT-IR and XPS spectroscopy measured for surface structure changes. Surface resistance decrease of implanted polymers was affected by ion implantation energy, ion species and ion dose rate. Surface conductivity of PET increased $2{\times}10^{9}$/∼$2{\times}10^{10}$/$\Omega$/sq by ion implantation. Result of various spectroscopy analysis, the cause of increasing PET surface conductivity was expected to breaking C=O bonds. It was formation carbon network structure by promote cross-linking and create C-C, C=C bonds.

• Journal of Adhesion and Interface
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• v.19 no.2
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• pp.74-82
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• 2018

Many methods for cross-linking acrylic PSAs have been discussed previously. For high cross-linking density, epoxy functionalized monomer and methyl aziridines as cross-linking agents were used in this study. Additionally, photopolymerization using different UV doses was investigated to synthesize a binder because of its rapid productivity. FT-IR analysis, curing behaviours and adhesion performance were examined for the relationship between UV doses and temperature as curing conditions. According to the results, the gel fraction was over 50% even at $120^{\circ}C$ after UV curing at a dose of $800mJ/cm^2$. On the other hand, while gel fractions of all samples reached approximately 80% only at $180^{\circ}C$ in thermal curing for 1 hour, gel fractions of the samples after thermal curing for 3 hours increased rapidly above $120^{\circ}C$ regardless of UV doses and reached approximately 100% at $180^{\circ}C$. This means that the second cross-linking reaction, esterification, is mainly dependent on the curing temperature.

• Korean Journal of Clinical Pharmacy
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• v.8 no.2
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• pp.122-132
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• 1998

SB-31 which contains Pursatilla, Licoris and Ginseng extracts was recently proved as an anticancer agent. In a preclinical effort to be applied this drug to human, pharmacokinetics of SB-31 was carried out in rats and rabbits. Glycyrrhizin(GZ), a saponin of Licoris was used as a standard ingradient for the pharmacokinetics of SB-31. The rat's blood, bile and urine samples were serially collected in femoral vein, common bile duct and bladder, respectively, after bolus i.v. injection at a dose of 1 or 1/5 ampul/rat and rabbit's blood samples from the marginal ear vein at a dose of 1 or 3 amp./rabbit. GZ and glycyrrhetic acid(GA), a major metabolite of GZ in the physiological samples were analysed by HPLC with UV detection. The decline of GZ in plasma concentration was generally biexponential at each dose. GZ was almost completely recovered in bile within 18 hour. GA wasn't detected in the samples with UV detector. In the rat, Vss and Kel at a dose of 1 and 1/5 ampul of SB-31 were $98.06\pm6.07\;ml,\;0.33\pm0.05\;hr^{-1}\;and\;65.46\pm11.19\;ml,\;0.68\pm0.25\;hr^{-1}$, respectively. Those in rabbits at a dose of 3 and 1 ampul of SB-31 were $235.24\pm30.72\;ml,\;0.13\pm0.36\;hr^{-1}\;and\;341.32\pm28.58\;ml,\;0.27\pm0.04\;hr^{-1}$, respectively. 'WinNonlin' was utilized for the compartmental analysis. A two-compartment model was chosen as the most appropriate pbarmaco-kinetic model. The data were best described by using a weighting factor of $1/y^2$. To evaluate the effect of SB-31 on cardiovascular system, serially diluted SB-31 was directly injected into coronary artery in the isolated perfused rat heart and the effect of PSF, PSH, saponins of Pursatilla, and SB-31 on PT, APTT of healthy human plasma was examined. Except the positive inotropic effect of ten times diluted solution of SB-31, there was no significant effect on LVDP, (- dp/dt)/(+dp/dt), heart rate and coronary flow in comparision with that of vehicle. SB-31 had no effect on PT but slightly delayed APTT about $6.9{\sim}11.5\%$. There was no significant effect of PSF and PSH on PT & APTT. Conclusively, SB-31 did not show any notable toxic effects on cardiovascular system.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.3
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• pp.251-257
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• 2013

In this study, ultraviolet protection factor (Sun Protection Factor, SPF) was investigated to provide basic data for subject safety and research of ultraviolet (UV) irradiation test in the future. Trial subjects (395 people) of skin type I, II, and III were evaluated according to skin type standard table. After measuring the skin color using a colorimeter, ITA (Individual Typology Angle) value was calculated. Subjects with 28 and above ITA value were positioned comfortably to be UV irradiated for 60 s and erythema was evaluated 24 hours after application. MED (Minimal Erythema Dose) was investigated where the minimal amount of erythema existed among UVB irradiated area. Statistical analysis was investigated using Statistical Package the Social Sciences program. As a result, the darker skin color results in the higher MED value since the higher skin type number results increased MED value and female has higher MED value than male since female has darker skin type than male. There was no relation between MED difference by ages in all different ages. However, it is hard to draw a conclusion as above since the number of subjects were not sufficient to support statistical significance for MED values by different ages. However, MED values by skin types obtained through this study can be used as a standard when MED value is expected to evaluate efficacy of sunscreen product and as basic data for further safety of clinical researches.