• Proceedings of the KSME Conference
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• 2001.11b
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• pp.42-47
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• 2001

The heat (mass) transfer characteristics on the blade surface of a first-stage turbine rotor cascade for power generation has been investigated by employing the naphthalene sublimation technique. A four-axis profile measurement system is successfully developed for the measurements of the local heat (mass) transfer coefficient on the curved blade surface. The experiment is carried out at the free-stream Reynolds number and turbulence intensity of $2.09\times10^5$ and 1.2%. The results on the blade surfaces show that the local heat (mass) transfer on the suction surface is strongly influenced by the endwall vortices, but that on the pressure surface shows a nearly two-dimensional nature. The pressure surface has a more uniform distribution of heat load than the suction one.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.741-744
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• 2003

In this study, the influence of chemical admixture on early strength development of concrete is discussed. According to the results, fluidity with variation of kinds of chemical admixture is lower in the case of acceleration type than in the case of normal type. Setting time of naphthalene acceleration type is shortened by I hour, and that of melamine is nearly same, but that of polycarbonic acid is somewhat retarded in comparison with that of naphthalene normal type. Early compressive strength gains 5MPa in about 18hours regardless of the kinds of chemical admixture. But as time elapses, compressive strength is higher in order of polycarbonic acid, naphthalene and melamine type. The relativity between compressive strength and the rebound value of P-type schmidt hammer is also favorable at early age, and compressive strength of 5MPa is estimated at the rebound value of 22.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_4
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• pp.165-172
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• 2001

We investigated the optimal experimental conditions and reaction kinetics for the decompositions of PCE, TCE, naphthalene, and chloroform using conventional Fenton oxidation process. Additionally, the influence of pH on the decompositions of PCE was also evaluated. The results indicated that the optimal pH value was around 3. The dosage of Fenton's reagent and the molar ratio of hydrogen peroxide to ferrous ion for an approximately complete decomposition was found to depend on the properties of the organic compound. Due to their unsaturated structures, the results show that PCE, TCE, and naphthalene could be all effectively decomposed by Fenton's reagent oxidation. Their unsaturated structures could be mostly destoyed within first 1-2 minutes at a low dosage with an certain molar ratio of hydrogen peroxide to ferrous ion. However the saturated compound such as chloroform was more difficult to decompose even with a relatively high dosage of Fenton's reagent.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.177-181
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• 2000

A lab-scale slurry reactor was developed for the treatment of contaminated sediments with polycyclic aromatic hydrocarbons (naphthalene, phenanthrene). In this system, range from 85 to 95% of PAHs with 2~3 rings were degraded within 11 days. Higher naphthalene degradation(94.05%) over phenanthrene degradation(87.07%) was probably due its higher solubility. Both compounds were not detected in aqueous phase after 7days and only 26.8% of naphthalene and 49.1% of phenanthrene were biodegraded. Removal TPH(Total Petroleum Hydrocarbon) concentration in solid after 11 days of treatment was 46%.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.286-289
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• 2000

Surfactants have been extensively considered for decontamination of the subsurface polluted with hydrophobic organic compounds. Enhanced solubilization of naphthalene and phenanthrene in surfactant solution of SDDBS, MADS12 and DADS12 was studied for single compounds and their binary mixture. The order of increasing solubility enhancement of naphthalene and phenanthrene is SDDBS < MADS12 < DADS12. The solubility enhancement of phenanthrene is more than that of naphthalene because of the higher hydrophobicity. A synergistic effect on the solubilization of two PAHs was observed in the presence of another PAH.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.191-194
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• 2005

Characteristics of sorption and desorption in soils affect chemical fate, soil-remediation time, and selection of remediation technology. The sorption and desorption behavior of atrazine and naphthalene on soils was studied. Six soils collected at Gwangju area were used as sorbents and the organic matter contents ranged from 1.28 to 5.21%. Sorption and desorption experiments were conducted and sorption distribution coefficients(Kd) of atrazine and naphthalene were nearly linear$(R^2=0.93{\sim}0.97)$. Desorption parameters were evaluated using three site desorption model included equilibrium, nonequilibrium and nondesorption sites. Non-desorbable site fraction for atrazine was evaluated, but for naphthalene it was not enumerated during the experimental period. Through the series dilution desorption experiments, non-desorpbable sites were observed for both chemicals.

• Journal of Microbiology
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• v.39 no.4
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• pp.338-342
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• 2001

Pseudomonas fluorescens SM11 is a naphthalene-degrading strain whose dissimilatory genes are cho-mosomally encoded. We have cloned the 2.9 kb Sal I fragment harboring genes for the naphthalene-degrading upper pathway. The nucleotide sequences were determined to be nahQ, napA, and partial regions of nahE genes. The nahQ encods a protein of 188 amino acid residues with a deduced molec-ular wight of 20.8kDa. The high homology with other proteins suggests that NAhQ may be an active and useful protein whtich gives as selective advantage to naphthalene degradatin. Transposase(TnpA)encodes a polypetide chain with a molecular mass of 41.8kDa consisting of 376 amino acid residues. The deduced anino acid sequence of tnpA revealed 96% idenitity with putative transposase of P. stutzeri OX1,. It was assumed that transposase plays an important role in the evloution of the catabloic-path way in the regulation of nah expression.

• Bulletin of the Korean Chemical Society
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• v.28 no.8
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• pp.1256-1260
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• 2007

Two β-diketone derivatives bearing triphenylene (1-naphthalene-2-yl-3-triphenylen-2-yl-propane-1,3-dione (NTPD)) and naphthalene (1,3-di-naphthalene-2-yl-propane-1,3-dione (DNPD)) and their Ln(III) complexes (Ln = Er or Gd) were synthesized and their photophysical properties were investigated. The sensitized emission of Er3+ ion in Er3+-[NTPD]3(terpy) and Er3+-[DNPD]3(terpy) was observed upon excitation at absorption maximum of ligands. Their photophysical studies indicate the sensitization of Er3+ luminescence by energy transfer through the excited triplet state of β-diketone ligand. The energy transfer rate through the excited triplet state of β-diketone ligand to Er3+ ion occurs faster than that of the oxygen quenching rate.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1242-1247
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• 2000

Results from a study on the effect of the chemical agent on the flowing and setting properties of high flowing.high strength concrete using blast-furnace slag are presented in this paper. The flowing and setting properties of concrete are investigated by slump, slump-flow, flowing velocity, L-flow, velocity of V-funnel, L-spatial passability and setting time. In addition, kinds of chemical agent were composed of naphthalene type, of naphthalene and melamine and melamine type. The results indicate that dispersive capacity can be increased by naphthalene composition. Also, it shows that viscosity and early strength can be increased by melamine composition.

• Bulletin of the Korean Chemical Society
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• v.26 no.6
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• pp.943-946
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• 2005

An effective spectrophotometric determination of palladium with 4-(2-pyridylazo)-resorcinol (PAR) using molten naphthalene as a diluent has been studied. A red complex of palladium with PAR is formed at 90 ${^{\circ}C}$. In the range of pH 9.0-11.0, the complex is quantitatively extracted into molten naphthalene. The organic phase is anhydrously dissolved in $CHCl_3$ to be determined spectrophotometrically at 520 nm against the reagent blank. Beer’s law is obeyed over the concentration range of 0.1-2 ${\mu}g{\cdot}mL^{-1}$. The molar absorptivity and Sandell’s sensitivity are 8.0 ${\times}\;10^5\;L{\cdot}mol^{-1}{\cdot}cm^{-}1\;and\;0.49\;{\mu}g{\cdot}cm^{-2}$ respectively. From the results of tolerance limits, it was found that there was no interferences were observed for most of the ions examined and those somewhat high interferences by Co(II), Fe(II) and Bi(III) could be effectively masked by EDTA.