• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.45-49
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• 2003

The solubility and stability of ondansetron hydrochloride (OS) in various vehicles were determined. The effect of cyclodextrins (CD) on the solubility of OS in water was determined by equilibrium solubility method. The solubility of OS at $32^{\circ}C$ increased in the rank order of isopropyl myristate (IPM) < propylene glycol laurate (PGL) ${\ll}$ propylene glycol monolaurate < propylene glycol monocaprylate (PGMC) < poly(ethylene glycol) 400 < diethylene glycol mono ethyl ether (DGME) < ethanol < poly(ethylene glycol) 300 < water (36.1 mg/ml) ${\ll}$ propylene glycol (PG) (283 mg/ml). The addition of PG or DGME to non-aqueous vehicles such as IPM, PGL and PGMC markedly increased the solubility of OS. The addition of CDs in water increased the solubility. Apparent stability constant for the CD complexation with OS was calculated to be $25.5\;M^{-1}$ for $2-hydroxypropyl-{\beta}-CD\;(2HP{\beta}CD)$. Twenty mM ${\beta}-CD$, 69.4 mM sulfobutyl ether ${\beta}-CD$ and 115.4 mM $2HP{\beta}CD$ increased the aqueous solubilty of OS 1.27, 2.18 and 1.85 times, respectively. OS was stable in buffered aqueous solution (pH 5.0). However, OS was relatively unstable in non-aqueous vehicles in the order of PG

• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.467-472
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• 2009

Ultraviolet curable coating solution was prepared with poly(ethylene glycol) acrylate oligomer and various mono and multi-functional acrylate monomers. The optical properties of UV cured coating layer on PET film with acrylate coating solution containing metal oxides, such as fumed silica and alumina, were also investigated to reduce light reflection on films. Poly(ethylene glycol) diacrylate which has 575 of average molecular weight was used as oligomer acrylate, and pentaerythritol triacrylate and dipentaerythritolpenta-/hexa acrylate were used as multi-functional acrylate monomers. Also, butyl acrylate was used to improve the adhesion as well as to reduce glass transition temperature to give a better flexability. 1-hydroxy cyclohexyl phenyl ketone was used as photoinitiator. We found out the metal oxides in acrylate coating solution showed a homogeneous dispersion from energy dispersive spectroscopy data. Transmittance and light reflection of coated PET film was measured with UV/vis spectrometer and gloss meter, respectively. When 1.00 g of both metal oxides was added into coating solution, the transmittance and the glossiness were reduced from 90% to 30% and from 190 GU to 35 GU, respectively. However, adding up to 1.00 g of the metal oxide into coating solution did not affect on the hardness of coating layer and adhesion between coated layer and PET film. Conclusively, we can control transmittance and light reflection of coated film by adjusting the amounts of metal oxide in coating solution.

• Proceedings of the IEEK Conference
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• 2004.08c
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• pp.675-679
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• 2004

The existing conjugated blue emitting material polymer which has been used for the two-wavelength method white-emission has good stability and low operating voltage as merits, but the imbalanced carrier transport has been indicated as problem area. We have introduced a novel blue emitting material having perylene moiety unit with hole transporting ability and blue emitting property and triazine moiety unit with electron transporting ability into the same host chain. We have synthesized N-[p-(perylen-3-y1)pheny1]methacry1 amide (PPMA) monomer and [N-(2,4-dipheny1-1,3,5-triazine)pheny1 methacry1 amide] (DTPM) monomer having blue light-emitting unit and electron transport unit, respectively by three steps. A novel non-conjugated blue emitting material Poly[N -[p­(perylene-3-y1) pheny1] methacry1 amide-co-N-[P-(4,6-dipheny1-1,3,5-triazine-2-y1]pheny1]methacry1 amide] (PPPMA-co-DTPM) copolymer having electron transporting unit was synthesized by the solution polymerization of PPMA and DTPM monomers with an AIBN initiator and showed high yield of $75{\%}$. It was very soluble in common organic solvents, and the fabrication of the thin film using a spin coating method was very simple. The PPPMA exhibited a good thermal stability.

• Journal of the Korean institute of surface engineering
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• v.38 no.1
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• pp.44-48
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• 2005

We prepared nickel silicide layers from p-Si(l00)/SiO₂(2000 Å)/poly-Si(700 Å)/Ni(400 Å) structures, feasible for gates in MOSFETs, by annealing them from 500℃～900℃ for 30 minutes. We measured the color coordination in visible range, cross sectional micro-structure, and surface topology with annealing temperature by an UV-VIS-IR spectrometer, field effect scanning electron microscope(FE-SEM), and scanning probe micro-scope respectively. We conclude that we may identify the nickel silicide by color difference of 0.90 and predict the silicide process reliability by color coordination measurement. The nickel silicide layers showed similar thickness while the columnar grains size and surface roughness increased as annealing temperature increased.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1647-1653
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• 2014

9,10-Bis(bromomethyl)phenanthrene reacted with fullerenes via a Diels-Alder reaction to give phenanthrene-substituted fullerene mono-adducts (PCMA) and bis-adducts (PCBA) as electron acceptors for organic photovoltaic cells (OPVs). The syntheses of the fullerene derivatives were confirmed by $^1H$ $^{13}C$ NMR spectroscopy and MALDI-TOF mass spectrometry. PCMA and PCBA showed better light absorption in the UV-visible region than $PC_{61}BM$. Their electrochemical properties were measured using cyclic voltammetry. Accordingly, the lowest unoccupied molecular orbital (LUMO) energy levels of PCMA and PCBA were -3.66 and -3.57 eV, respectively. Photovoltaic cells were fabricated with a ITO/PEDOT:PSS/poly(3-hexylthiophene)(P3HT):acceptor/LiF/Al configuration, where P3HT and PCBA are the electron donors and acceptors, respectively. The polymer solar cell fabricated using the P3HT:PCBA active layer showed a maximum power conversion efficiency of 0.71%.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.12
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• pp.120-126
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• 2002

The needs of ultra-precisely machined parts are increasing more and more. But the experimental data required to ultra precision machining of nonferrous metal is insufficient. The behavior of cutting in micro cutting area is different from that of traditional cutting because of the size effect. Copper is widely used as optical parts such as LASER reflector's mirror and multimedia instrument. In experimental, after oxygen-free copper is machined by ultra precision machine with natural mono crystal diamond tool (NCD) and synthetic poly crystal diamond tool (PCD), we compared chip formation and tool's wear according to used tool. Also, we researched optimized cutting condition with the results measured according to cutting condition such as spindle speed, feed rate and depth of cut. As a result, the optimal working condition that makes good surface roughness is obtained. The surface roughness is good when spindle speed is above 80 m/min, and feed rate is small and depth of cut is above 0.5 ${\mu}{\textrm}{m}$. In cutting of klystron anode and cavity 3.2 nmRa of surface roughness is obtained.

• Journal of Environmental Science International
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• v.22 no.6
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• pp.773-777
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• 2013

This study examined the effects of cage rearing system and backyard raising system on fatty acid profile of egg in laying hens during 9 weeks. Two hundred hens, 70-wk-old, Hy-line Brown, were used in this study and fed basal diets. 100 hens, randomly collected from facility, were transferred to cage rearing system and 100 remaining hens were moved to backyard raising system. For overall period, higher unsaturated fatty acid percentages in two different rearing systems than did saturated fatty acid (SFA) were observed. In unsaturated fatty acid compositions, both rearing system showed a higher mono unsaturated fatty acid (MUFA) contents than poly unsaturated fatty acid (PUFA) contents. Egg quality traits of laying hens reared in backyard system had considerably lower contents of SFA and higher contents of MUFA compared with eggs from cage rearing system (P<0.05). In addition, eggs from cage rearing system resulted in a significantly lower n-3 contents and higher n-6:n-3 ratios and CLA contents in comparison with backyard raising system (P<0.05). However, no significant effects of two different rearing systems on PUFA, PUFA:SFA ratio, and n-6 contents were observed during the experimental period. In conclusion, this result suggests that cage rearing system and backyard raising system will play an important role in improving egg production as functional foods.

• KIEAE Journal
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• v.13 no.5
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• pp.111-118
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• 2013

This study aims to investigate advantages of complex installation of green roof and PV system in a public building, to analyze the impact of green roof on the efficiency of PV power generation, and to consider the correlation between green roof and PV power generation. When the temperature and power generation of the modules installed in the green roof and non-green roof of the public building were measured for 3 days, the average temperature of the green roof was 23.6 degrees, and it was 36.1 degrees in the non-green roof which increased by nearly 53%. Overall, the module temperature in the green roof was lower. On the other hand, in relation to the PV generation depending on temperature reduction during the same period, the mono-crystalline module and the poly-crystalline module in the green roof showed an increase in generation at nearly 222.2W and 341.6W, and the efficiency rose by 5.5% and 6.2%, respectively, compared to the modules in the non-green roof. Therefore, it is analyzed that green roof has a positive influence on PV power generation. Finally shows the efficiency of the installed on the Green Roof PV system (complex Installation) higher than on the concrete roof PV system. Thus, the complex PV systems as well as the usual benefits of green roofs will provide greater synergies.

• Proceedings of the Korean Society of Rheology Conference
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• 2002.05a
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• pp.25-27
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• 2002

In this study we investigated the reaction kinetics by a convenient but useful method-rheology to characterize the interface between two immiscible blends with a Reactive compatibilizer. Also, we made an attempt to correlate changes of interface roughness with rheological properties. The blend systems employed in this study was mono-carboxylated polystyrene (PS-mCOOH) and an poly(methyl methacrylate-ran-glycidylmethacrylate) (PMMA-GMA). PS-mCOOH was synthesized by an anionic polymerization and PMMA-GMA by a free radical polymerization. We prepared two plates of each polymer using compression molding with a smooth surface molder, then put one upon another. As soon as these two plates welds together inside a rheometer under nitrogen environment, the torque and moduli were obtained with reaction time at different temperatures. Through the analysis of this modulus change with reaction time, we estimated interfacial reaction and roughening. The increment of modulus in initial state can be correlated to the extent of reaction. We obtained the reaction kinetic constant by fitting appropriate kinetic equation into experimental data. We also showed that increment of modulus in later state was due to by roughened interface.

• Textile Coloration and Finishing
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• v.11 no.4
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• pp.1-7
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• 1999

Urethane-acrylate propelymers for secondary coating of optical fiber and high - performance material were prepared from the 4,4'-diphenylmethane diisocyanate(MDI), poly(tetramethylene oxide)glycol(PTMG, Mw 650 or 1000), 1,6-hexanediol(HD), 2-hydroxyethyl acrylate(HEA), and dibutyltin dilaurate as a catalyst. UV-Curable polyurethane acrylates were formulated from the urethane-acrylate prepolymers, three types of reactive diluents(DTs) having mono-, di-, and trifunctional-phenoxyethyl acrylate(PEA), hexanediol diacrylate(HDDA), and trimethylolpropane triacrylate(TMPTA), and 1-hydtoxycyclohexyl phenyl ketone(Irgacure 184) as a photoinitiator. The UV-cured films of polyurethane acrylates were obtained by curing using a medium-pressure mercury lamp(U W/cm, $\lambda_{max}=365\;nm)$. In this work, the effects of molecular weights of polyol and diol with low molecular weight into polymer chain on mechanical and dynamic mechanical properties of UV-cured polyurethane acrylates were studied. The structure and properties of the films obtained from the UV photopolymerization of urethane-acrylate prepolymer were investigated by FT-IR spectroscopy, dynamic mechanical measurement, tensile testing, and X-ray diffractometry.