• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.373-376
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• 2016

Transition metal dichalcogenides (TMDs) such as $MoS_2$ is the thinnest semiconductor, exhibits promising prospects in the applications of optoelectronics, catalysis and hydrogen storage devices. Uniform and high quality $MoS_2$ is highly desirable in large area for its applications on commercial scale and fundamental research. Many experimental techniques i.e CVD have been developed to successfully synthesis $MoS_2$ on large scale, here in this work atomistic detail to understand the growth mechanism is addressed which was greatly overlooked. Here based on first principles calculation we found that polarity of seeding promter (crystal violet considerd in this work) controls the growth mechanism. It is also found that molybdenum destroys the precursor while sulfur adsorption with precursor is favorable.

• Restorative Dentistry and Endodontics
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• v.4 no.1
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• pp.29-34
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• 1978

The purpose of this study was to measure penetration of dye stuff(5% Methylene blue, Hematoxylin, Crystal violet and Safranin-O) on silicate cement, Adaptic, Hi-pol and unfilled resin. Each filling material was mixed on the mixing pad and the mixed material was inserted with condensation force of 500gr, 1000gr and 2000gr and without condensation force into preformed glass tube (10mm in diameter and 10mm in height). The specimen was stored in the air for 24 hours, then specimen was immersed in various dye solution (5% methylene blue, hematoxin, crystal violet and safranin-O) for different period of time (l hour and 24 hours). These dye-treated specimen was cut horizontally at the middle portion and the dye penetration in cut surface was measured. Following results were obtained. 1. Pentration of various dye was excessive in silicate cement with and without Condensation force. 2. There has been no evidence of dye penetration in unfilled resin. 3. Dye penetration occurced with in 1 hour period and the extending time didn't affect the dye penetration.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.5
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• pp.163-167
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• 2020

Ring-shaped SiC (Silicon carbide) polycrystals used as an inner material in semiconductor etching equipment was manufactured using the PVT (Physical Vapor Transport) method. A graphite cylinder structure was placed inside the graphite crucible to grow a ring-shaped SiC polycrystal by the PVT method. The crystal polytype of grown crystal were analyzed using a Raman and an UVF (Ultra Violet Fluorescence) analysis. And the microstructure and components of SiC crystal were identified by a SEM (Scanning Electron Microscope) and EDS (Energy Disruptive Spectroscopy) analyses. The grain size and growth rate of SiC polycrystals fabricated by this method was varied with temperature variation in the initial stage of growth process.

• Journal of Life Science
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• v.18 no.10
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• pp.1331-1335
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• 2008

A Klebsiella pneumoniae WL-5 with the capability of decolorizing several recalcitrant dyes was isolated from activated sludge of an effluent treatment plant of a textile and dyeing industry. This strain showed a higher dye decolorization under static condition and color removal was optimal at pH 6-8 and $30-35^{\circ}C$. More than 90% of its color of Congo Red were reduced within 12 hr at $200\;{\mu}M$ dye concentration. Malachite Green, Brilliant Green and Reactive Black-5 lost over 85% of their colors at $10\;{\mu}M$ dye concentration, but the percentage decolorization of Reactive Red-120, Reactive Orange-16, and Crystal Violet were about 46%, 25%, and 13%, respectively. Decolorizations of Congo Red and triphenylmethane dyes, such as Malachite Green, Brilliant Green, and Crystal Violet were mainly due to adsorption to cells, whereas azo dyes, such as Reactive Black-5, Reactive Red-120, and Reactive Orange-16 seemed to be removed by biodegradation through unknown enzymatic processes.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.16 no.6
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• pp.267-272
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• 2006

A series of $Sr_{1-x}Ca_xGa_2S_4:Ce,Na$ phosphors have been synthesized by solid-state reaction. The photoluminescence and structural properties of $Sr_{1-x}Ca_xGa_2S_4:Ce,Na$ have been examined. The $Sr_{1-x}Ca_xGa_2S_4:Ce,Na$ phosphors have a strong absorption at 400 nm, which is the emission wavelength of a violet light emitting diode (LED). The emission peaks of $SrGa_2S_4:Ce,Na$are located at 448 nm and 485 nm. The partial replacement of Sr by Ca in $Sr_{1-x}Ca_xGa_2S_4:Ce,Na$ causes a red shift of emission wavelengths. The $Sr_{1-x}Ca_xGa_2S_4:Ce,Na$ can be used as blue emitting phosphors pumped by the violet LED for fabricating the multi-band white LED.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.5
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• pp.183-189
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• 2014

This study was conducted to study the influence of Co and Fe on the color of glaze and diopside crystals in the diopside crystal glaze empirically produced and used by ceramic artists, in case of adding $Co_3O_4$ and $Fe_2O_3$. As a result, the color of glaze was blue when $Co_3O_4$ was added to the diopside crystal glaze and the diopside crystals appeared pastel violet with Co included. When $Fe_2O_3$ was added to the diopside crystal glaze, the color of glaze appeared brown and the color of diopside crystals was goldenrod with Fe included. The crystals precipitated on the surface of diopside consisted of diopside crystals and diopside precursors. With longer retention time, the amount of diopside precursors decreased and the amount of diopside crystals increased. Also, Co was more easily included by the diopside crystals than Fe was and crystallizability of dispside was improved in case of including Co. Including Fe lowered peak intensity of properties and partially dissolved the diopside crystals.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.128-132
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• 2013

L-Arginine semi-oxalate (LASO) single crystal has been grown by solution growth technique at room temperature. The crystal structure and lattice parameters were determined for the grown crystal by single crystal X-ray diffraction studies. Photoluminescence studies confirm the violet fluorescence emission peak at 395 nm. Optical constants like band gap, refractive index, reflectance, extinction coefficient and electric susceptibility were determined from UV-VIS-NIR spectrum. The dielectric constant, dielectric loss and ac conductivity of the compound were calculated at different temperatures and frequencies to analyze the electrical properties. The solid state parameters such as plasma energy, Penn gap, Fermi energy and polarizability were calculated to analyze second harmonic generation (SHG). Nonlinear optical property was discussed to confirm the SHG efficiency of the grown crystal.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.165-167
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• 1998

Nd:YAG crystals were grown by Horizontal Bridgman method. The effects of sliding rate (growth rate) of Molydbenum container, growth atmosphere and concentration of Neodymium ions on crystal qualities were investigated. The size of the crystals grown was up to 150-200 mm in length, 70 mm in width and 25-35 mm in thickness. Crystals grown under the optimum conditions were violet, transparent and could not be observed any macroscopic defects. Under the polarizing microscopoc observations with crossed polar, striations, {211} facets and inclusions were detected. With the grown crystals, prototypes of laser rods for 1.06$\mu$m laser application were manufactured and then characterized. As a result, we can get high quality of Nd:YAG laser rods with <111> and <110> axis, 63 mm in length and6.3 mm in diameter.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.3
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• pp.108-112
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• 2007

Cubic Zirconia single crystals having changeable color with light source were grown by skull melting method. Strong absorption of yellow color region light by Co and Nd and the absorption in violet color region by Fe led the color change from blue-green to red-purple with the light source from fluorescent to incandescent lamp. Color of crystals varied not only by the dopants but yttria contents and the conditions far heat treatment.

• Microbiology and Biotechnology Letters
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• v.25 no.6
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• pp.630-635
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• 1997

Decolorization of congo red, methyl orange, poly R478, remazol brilliant blue R and crystal violet by white-rot fungus Trametes sp. CJ-105, isolated in Korea, was investigated. Remazol blue and methyl orange were almost completely decolorized after 2 days of culture, but congo red, crystal violet and poly R478 were decolorized by about 80%, 40% and 30% after 10 days of culture, respectively. As a result of determination of cell mass and enzyme activity, it was shown that color removal efficiency was related to cell mass and enzyme activity, and also found that only laccase (E.C.1.10.3.2) activity was existed in the culture broth. The decolorization ratios of remazol blue in the concentrations of 100ppm to 3, 000 ppm were 85% and above after 2 days of culture. In this study, we found that white-rot fungus, Trametes sp. CJ-105, was effective in decolorizing a wide range of structurally different synthetic dyes.