• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2863-2864
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• 2013

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1997.04a
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• pp.71-73
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• 1997

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1692-1694
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• 2004

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.242.1-242.1
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• 2003

The nucleoside analogue, L-FMUS was synthesized from L-FMAU which has been shown to have significant antiviral activity against hepatitis B virus (HBV). It was prepared by two steps. First, 5'hydroxyl of L-FMAU was substituted by thioacetyl group using diisopropylazodicarboxylate(DIAD), Triphenyl phosphine(PPh3) and thioacetic acid in anhydrous THF. (omitted)

• Analytical Science and Technology
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• v.28 no.3
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• pp.204-211
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• 2015

Lanthanide complexes have attracted much attention because of their unique light emitting property. The light-emitting efficiencies of europium β-diketonate complexes were compared with those of complexes coordinated by the ligands of amines or phosphine oxides. The results demonstrated that the complexes that were coordinated by phosphine oxides had higher light-conversion performance than those coordinated by amines. The highest light-emitting efficiency was observed when the ligand of trioctylphosphine oxide was coordinated. In order to determine the coordination equivalency of trioctylphosphine oxide in the above complexes, 31P-NMR and their photoluminescence spectra were measured. The findings showed that the europium β-diketonate complex had one or two coordination equivalencies of trioctylphosphine oxide according to the steric hindrance of its original ligand.

• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.694-700
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• 1992

Aromatic polyamides and polyesters with fexible spacers are prepared by Heck reaction with palladium catalysts In presence of carbon monoxide gas. Dichlorobis(triphenyl phosphine) plladium(II) ($PdCl_2(PPh_3)_2$) and palladium chloride ($PbCl_2$) are used as catalysts. Polyamides and polyesters prepared by his polymerization system have similar transition temperatures. Flexible spacer substituted on phenylene units are varied from hexyl to hexadecyl, the length of spacers effected on transition temperatures of substituted polymers.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.133-137
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• 1982

An experiment was conducted to find out the proper and effective fumigation method for harvested fresh chestnuts produced in Korea. Fumigation with phosphine, causing damages on chestnuts by rapid corruption or change in color on pericarp, did not completely kill chestnut curculio and nut fruit tortrix larvae in harvested fresh chestnuts regardless of long exposure of chestnuts to phosphine. Any damages not being appeared by fumigant, fumigation with methyl bromide at $40g/m^3$ for 4 hours at $21^{\circ}C$ would retain the low control against inclusion of any chestnut pests tested. Though fumigation with methyl bromide at $50g/m^3$ for 24hours was effective against any larvae of chestnut insects control, they caused serious damages by making the flesh surface of harvested fresh chests dark or dense brown. However, fumigation with methyl bromide at $50g/m^3$ for 4 hours at $21^{\circ}C$ resulted in complete kill of larvae of Curculio dentipes and Carpocapsa splendana in harvested fresh chestnuts with no significant damages on the treated fruits.

• Bulletin of the Korean Chemical Society
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• v.30 no.11
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• pp.2754-2758
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• 2009

Three novel phosphorescent 2-phenylpyridine-based iridium(III) complexes, $[(ppy)_2Ir(P\^{}N)]PF6\;(1),\;[(dfppy)_2Ir(P\^{}N)]PF_6$ (2), and $[(dfmppy)_2 Ir(P\^{}N)]PF6$ (3), where $P\^{}N$ = 2-[(diphenylphosphino)methyl]pyridine (dppmp), were synthesized and characterized. The absorption, photoluminescence, cyclic voltammetry and thermal stability of the complexes were investigated. The complexes showed bright blue luminescences at wavelengths of 448 $\sim$ 500 nm at room temperature in $CHCl_3$ and revealed that the $\pi$-acceptor ability of the phosphorous atom in the ancillary dppmp ligand plays an important role in tuning emission color resulting in a blue-shift emission. The single crystal structure of $[(dfmppy))_2Ir(P\^N)]PF_6$ was determined using X-ray crystallography. The iridium metal center adopts a distorted octahedral structure coordinated to two dfmppy and one dppmp ligand, showing cis C-C and trans N-N chelate dispositions. There is a $\pi-\pi$ overlap between π electrons delocalized in the difluorophenyl rings.

• Journal of Korean Vacuum Science & Technology
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• v.4 no.3
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• pp.73-77
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• 2000

Single crystal and polycrystalline Si thin films were doped with phosphorus by a 2-zone diffusion method to develop the low-resistivity polycrystalline Si electrode for a hemispherical grain. Solid phosphorus source was used in order to achieve uniformly and highly doped surface region of polycrystalline Si films having rough surface morphology. In case of 2-zone diffusion method, it is proved that the heavy doping near the surface area can be achieved even at a relatively low temperature. SIMS analysis revealed that phosphorus doping concentration in case of using solid P as a doping source was about 50 times as that of phosphine source at 750$^{\circ}C$. Also, ASR analysis revealed that the carrier concentration was about 50 times as that of phosphine. In order to evaluate the electrical characteristics of doped polycrystalline Si films for semiconductor devices, MOS capacitors were fabricated to measure capacitance of polycrystalline Si films. In ${\pm}$2 V measuring condition, Si films, doped with solid source, have 8% higher $C_{min}$ than that of unadditional doped Si films and 3% higher $C_{min}$ than that of Si films doped with $PH_3$ source. The leakage current of these films was a few fA/${\mu}m^2$. As a result, a 2-zone diffusion method is suggested as an effective method to achieve highly doped polycrystalline Si films even at low temperature.

• Journal of the Korean Chemical Society
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• v.45 no.1
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• pp.25-30
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• 2001

A selective kinetic fluorimetric method for the determination of trace rhodium(Ⅲ), based on the catalytic effect of rhodium(Ⅲ) on the oxidation of nile blue by periodate have been studied. The effects of pH and concentrations of nile blue, sodium periodate, trioctyl phosphine oxide(TOPO) and temperature were investigated. The calibration curve for rhodium(Ⅲ) ion was linear over the range from 100 ng/mL to 0.1 ng/mL and the detection limit was 0.01 ng/mL under the optimal experimental conditions. Effects of interferences from several cations and anions for the determination of rhodium(Ⅲ) were also investigated.