• Korean Journal of Materials Research
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• v.24 no.2
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• pp.93-97
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• 2014

In this study, a cobalt sulfate ceramic coating was sintered on various clays at $1250^{\circ}C$. The specimen characteristics were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM), TG-DTA, UV-vis spectrophotometer, and HRDPM. The ceramic coating had a constant thickness of thousands ${\mu}m$, and the surface was confirmed to be densely fused. Other new compounds were produced by the cobalt sulfate sintering process and reactions. These compounds were a $CoAl_2O_4$ phase, $Co_2SiO_4$ phase, anorthite($CaAl_2Si_2O_8$) phase, and $FeAl_2O_4$ phase, respectively. UV properties of the coated specimen were investigated, celadon clay specimen in 530-550 nm band is showing a dark gray color. The white clay and white mix clay specimen in 460-500 nm band is showing a blue color. The cobalt-aluminate($CoAl_2O_4$) spinel and the cobalt-silicate olivine($Co_2SiO_4$) were the strongest of the ceramic pigments, producing a very pure, navy blue color.

• Membrane and Water Treatment
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• v.10 no.3
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• pp.245-250
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• 2019

Prussian blue (PB) is well known for its excellent $Cs^+$ ions adsorption capacity. Due to the high dispersibility of PB in aqueous phase, composite materials imbedding PB in supporting materials have been introduced as a solution. However, building PB particles inside porous supporting materials is still difficult, as PB particles are not fully formed and elute out to water. In this study, we suggest layer-by-layer (LBL) assembly to provide better immobilization of PB on supporting materials of poly vinyl alcohol sponge (PVA) and cellulose filter (CF). Three different PB attachment methods, ex-situ/in-situ/LBL assembly, were evaluated using PB leaching test as well as $Cs^+$ adsorption test. Changes of surface functionality and morphology during PB composite preparation protocols were monitored through Fourier transform infrared spectroscopy and scanning electron microscopy. The results indicate that LBL assembly led to better PB attachment on supporting materials, bringing less eluting PB particles in aqueous phase compared to other synthesis methodologies, such as ex-situ and in-situ synthesis. By enhancing the stability of the adsorbent, adsorption capacity of PVA-PB with LBL improved nine times and that of CF-PB improved over 20 times. Therefore, the results suggest that LBL assembly offers a better orientation for growing PB particles on porous supporting materials.

• The Korean Journal of Zoology
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• v.12 no.3
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• pp.94-102
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• 1969

The protective action of methylene blue against gamma-irradiation was studied with rats. Albino rats were given 360 rads of whole-body gamma-irradiation following an intraperitoneal injection of physiological saline or methylene blue. Male rats given methylene blue (38mg/kg) and the control rats given saline were alive following gamma-irradiation. Serum lactic dehydrogenase (LDH) activity, and LDH isoenzyme patterns in serum and various organs were determined at various time intervals after the exposure. 1) The serum LDH level in both the control and methylene blue-treated rats was increased during the initial phase, but returned to the initial level thereafter. 2) Methylene blue showed a marked delay in the rise of serum LDH at 15 and 64 hours after exposure. 3) The exposure in the control and methylene blue-treated rats resulted in an increase in the relative amount of the more electrophoretically mobile-anodal isoenzyme (band 1) and a decrease in the least mobile-cathodal isoenzyme (band 5) in serum, liver, heart and testis nearly at 40 and 116 hours, respectively. 4) Isoenzyme patterns in serum, liver and testis after exposure were not significantly different between the control and the methylene blue-treated rats. 5) Methylene blue showed a slight delay in alteration of heart tissue LDH isoenzyme patterns after exposure. 6) The increase of serum LDH level after exposure is a reflection of an immediate increase in the H type, band 1 of LDH isoenzymes. 7) It is concluded from this study that methylene blue has a remarkable radioprotective action in the serum LDH activity and in the heart tissue LDH isoenzyme patterns.

• Journal of Microbiology
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• v.34 no.1
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• pp.101-104
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• 1996

The influences of culture parameters on the decolorization of anthron-type dye, Remazol brilliant blue R(RBBR) by Pleurotus ostreatus were studied in defined media. In the decolorization, 1-10 mM nutrient nitrogen and 40 mM glucose were effective whereas agitation and Tween 80 were not suitable. The decolorization occurred and the activity of extracellular peroxidase was detected during the stationary phase.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.12
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• pp.173-183
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• 1995

Blue light of 0.15mW at 417.6nm is generated in a quasi-phase-matched LITaO$_{3}$ optical waveguide. A new heat-treatment technique using a metal-oxide mask is proposed to fabricate the periodic domain-inverted grating with less degraded optical properties. The mask promotes the proton indiffusion by inhibition of the proton outdiffusion during the heat treatment. It reduces the amount of the initial proton exchange for the domain inversion and prevents the formation of crystal defects on the surface accompanied by the proton outdiffusion. Consequently, it minimizes the degradation of nonlinear coefficient and scattering loss caused by the initial proton exchange.

• Polymer Science and Technology
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• v.25 no.3
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• pp.201-204
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• 2014

• Applied Chemistry for Engineering
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• v.20 no.6
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• pp.632-637
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• 2009

Poly(${\varepsilon}-caprolacton$)/ethyl cellulose (PCL/EC) microcapsules containing pluronic F127 were prepared by a spray drying method. The aqueous phase, 20% of pluronic F127 was dissolved in distilled water, and the organic phase, 5% of PCL and EC were dissolved in dichloromethane. The microcapsules were obtained by spray drying the water-in-oil (W/O) emulsion. According to the data of scanning electron microscopy and particle analyzer, tens of micro size microcapsules were observed. On a differential scanning calorimeter, the phase transition temperatures of microcapsules were observed and they were found around those of pluronic F127 and poly(${\varepsilon}-caprolacton$), which were the main components of the microcapsules. At the range of $30{\sim}45^{\circ}C$, temperature-dependent release properties were investigated using fluorescein isothicyanate-dextran (FITC-dextran) and blue dextran as a model drug. When the temperature was increased, the degree of release of microcapsule was also increased. FITC-dextran, the relative low molecular weight, was more released than blue-dextran.

• Journal of the Korean Chemical Society
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• v.52 no.1
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• pp.16-22
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• 2008

on-line system for preconcentration and separation of lead(II) is presented. The method is based on the complex formation of Pb(II) with adsorbed Methyl thymol blue on activated carbon. The conditions of preparing the solid phase reagent and of quantitative recovery of Pb(II) from diluted solutions, such as acidity of aqueous phase, solid phase capacity, and flow variables were studied as well as effect of potential interfering ions. After preconcentration step, the metal ions are eluted automatically by 5 ml of 0.5 M HNO3 solution and the lead ions content was determined by flame atomic absorption spectrometry. Under the optimum conditions, the lead ions in aqueous samples were separated and preconcentrated about 1000-fold by the column. The detection limit was 0.001 g mL-1. Lead has been determined in river and tap water samples, with recovery of 98 to 102%.

• Journal of Powder Materials
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• v.11 no.2
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• pp.143-148
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• 2004

In the present study, $TiO_2$ imbedded composite powders have been successfully prepared from the (Cu. Zn)/$TiO_2$ composite salt solution. The composite (Cu, Zn)/$TiO_2$ powders were formed by drying the solution at 200~$600^{\circ}C$ in the hydrogen atmosphere. Photocatalytic characteristics was evaluated by detecting the decomposition ratio of aniline blue with UV-visible spectrophotometer(Shimazu Co., UV-1601). Phase analysis of (Cu, Zn)/$TiO_2$ composite powders was carried out by XRD and DSC, and powder size was measured with TEM. The mean particle size of composite powders was about 100mm. As the reduction temperature increases, a few zinc sulfide and oxide phases was formed and copper oxide phase was reduced. The decomposition ratio of aniline blue was about 80％ under the UV irradiation by the TiO$_2$ phase in the composite (Cu, Zn)/$TiO_2$ powders and similar decomposition ratio of 80％ was obtained at the UV lightless condition by virtue of Cu and Zn compounds.

• Journal of the Optical Society of Korea
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• v.20 no.6
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• pp.784-793
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• 2016

We present a single shot low coherence white light Hilbert phase microscopy (WL-HPM) for quantitative phase imaging of Si optoelectronic devices, i.e., Si integrated circuits (Si-ICs) and Si solar cells. White light interferograms were recorded by a color CCD camera and the interferogram is decomposed into the three colors red, green and blue. Spatial carrier frequency of the WL interferogram was increased sufficiently by means of introducing a tilt in the interferometer. Hilbert transform fringe analysis was used to reconstruct the phase map for red, green and blue colors from the single interferogram. 3D step height map of Si-ICs and Si solar cells was reconstructed at multiple wavelengths from a single interferogram. Experimental results were compared with Atomic Force Microscopy and they were found to be close to each other. The present technique is non-contact, full-field and fast for the determination of surface roughness variation and morphological features of the objects at multiple wavelengths.