• Journal of the Semiconductor & Display Technology
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• v.10 no.4
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• pp.31-35
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• 2011

For high efficiency of Si-cells, Si wafers were textured by the KOH and NaOH etching solution to decreas the reflectance at surfaces of the cells. The textured surfaces were shown various types such as isotropic and anisotropic depending on the etching solution. The reflectance at sample of an anisotropic form with pyramid type was lower than that of isotropic form. The surface with isotropic form of general tiny circles on the surface increased the efficiency, however, the reflectance of it was increased. The efficiency was increased on surface with low roughness.

• YAKHAK HOEJI
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• v.4 no.1
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• pp.43-46
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• 1959

A new quantitiative analytical method of prussic acid by "Microdiffusion analysis" was studied. HCN-Glucoside of ARMENIACA was hydrolysed with KOH in out-room of unit, and then concentrated sulfuric acid was poured in order to liberate the HCN gas. The liberated gas was absorbed into nickel sulfate solution of inner room of unit quantitatively. The excess of nickel sulfate was determined by EDTA Reagent using MX-indicator. By this method, the following results were obtained: (1) It was needed more than 4 hours, in order to hydrolyse completely at $50^{\circ}C$, but could be shortened to 3 hrs. at $^60{\circ}C$. (2) It was completely absorbed into nickel sulfate solution after 30min.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.237.2-237.2
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• 2003

DWP40458 is a novel human thrombopoietin mutein with two additional N-linked glycosylation site. The thermal stability of DWP40458 in both solution and lyophilized form was studied in the temperature range of 4-50$^{\circ}C$, compared with recombinant human TPO (rhTPO). When the aggregation or degradation pattern of DWP40458 and rhTPO solution was characterized by using SDS-PAGE, gel permeation chromatography (GPC) and reverse phase HPLC, it was found that thermostability of DWP40458 was significantly different to rhTPO in the temperature at 25, 40, 40, 50$^{\circ}C$. (omitted)

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.17 no.4
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• pp.172-178
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• 2007

Mica (muscovite) powders were synthesized by hydrothermal method (horizontal turning method). The hydrothermal conditions for the synthesis of mica were prepared by the ratio of $K_2O : Al(OH)_3 : SiO_2$ = 1 : 3 : 3 mol% as the starting materials with KOH (8 mol%) solution as the hydrothermal solvent and reaction temperature at $260^{\circ}C$ for 72hrs. The synthetic powder used for preparation of nano silver coated mica by vertical hydrothermal treatment. The hydrothermal conditions for the treated as nano silver coating were prepared by the synthetic powder as raw materials, triple distilled water ($0.5{\ell}$) solution as the hydrothermal solvent with nano silver sol (1,000 ppm) as the material of nano silver coating and reaction temperature at $160{\sim}260^{\circ}C$ for 72 hrs. After hydrothermal treatment, structural, judgment of nano silver coating and character of nano silver coated mica were examined by XRD, SEM, TEM-EDX and shake plask method.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.12 no.3
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• pp.126-132
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• 2002

The nanocrystalline zirconia powder with anisotropic shapes was synthesized by hydrothermal treatment of the tetragonal zirconia prepared by aging the zirconium hydroxide precipitate, which was obtained from the reaction between $ZrOCl_2{\cdot}8H_2O$ and KOH solutions under the fixed pH of 13.5, at $100^{\circ}C$ for 24 h. With increasing the hydrothermal reaction temperature and time, the fraction of tetragonal phase with spherical zirconia decreased, whereas, relatively the fraction of monoclinic phase with spindle-like and rod shape zirconia increased. As increased concentration of the NaOH solution it promoted the particle size to become larger and the crystalline phase to transform tetragonal to monoclinic. However, the specific surface area at the early stage of the reaction increased and subsequently decreased because of grain growth in powder with longer reaction time.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.1
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• pp.47-53
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• 2012

As one of the methods for recycling the FRP from the waste ships, separation of roving layer from the mat has some merits in a sense of the eco-friendly and economical recycling process. Similar characteristics, however, between the roving and the mat even with different ratio of the resin and the glass and the thickness of the roving, much thinner than the mat, make the mechanically automatic differentiation difficult. In this study spectrochemical differentiation between the two layers has been made using boiling concentrated sulfuric acid, methanol and isopropanol solution saturated with KOH, or hydrogen fluoride (HF) solution. Furthermore efficiently coloring water-soluble dye following the HF treatment makes the roving layer more distinguishable photophysically. The layer differentiation and the automatic layer distraction move up the date of simple and automatic separation process for the waste FRP.

• Journal of the Korean Society for Marine Environment & Energy
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• v.12 no.1
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• pp.55-59
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• 2009

As one of the methods for recycling the FRP from the small and medium waste ships, separation of roving layer from the mat has some merits in a sense of the recycling energy and the environmental effects. Similar characteristics, however, between the roving and the mat even with different ratio of the resin and the glass and the thickness of the roving, much thinner than the mat, make the mechanically automatic differentiation difficult. In this study spectrochemical differentiation between the two layers has been made using (1) boiling concentrated sulfuric acid which can dissolve the resin in the FRP layer, (2) methanol and isopropanol solution saturated with KOH which can dissolve the glass, or (3) hydrogen fluoride(HF) solution which can reacts with $SiO_2$ fragments of the glass. Furthermore coloring water-soluble dye following the HF treatment makes the roving layer more distinguishable photo-physically.

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.29.1-29.1
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• 2009

Fabrication of good quality P-type GaN remained as a challenge for many years which hindered the III-V nitrides from yielding visible light emitting devices. Firstly Amano et al succeeded in obtaining P-type GaN films using Mg doping and post Low Energy Electron Beam Irradiation (LEEBI) treatment. However only few region of the P-GaN was activated by LEEBI treatment. Later Nakamura et al succeeded in producing good quality P-GaN by thermal annealing method in which the as deposited P-GaN samples were annealed in N2 ambient at temperatures above $600^{\circ}C$. The carrier concentration of N type and P-type GaN differs by one order which have a major effect in AlGaN based deep UV-LED fabrication. So increasing the P-type GaN concentration becomes necessary. In this study we have proposed a novel method of activating P-type GaN by electrochemical potentiostatic method. Hydrogen bond in the Mg-H complexes of the P-type GaN is removed by electrochemical reaction using KOH solution as an electrolyte solution. Full structure LED sample grown by MOCVD serves as anode and platinum electrode serves as cathode. Experiments are performed by varying KOH concentration, process time and applied voltage. Secondary Ion Mass Spectroscopy (SIMS) analysis is performed to determine the hydrogen concentration in the P-GaN sample activated by annealing and electrochemical method. Results suggest that the hydrogen concentration is lesser in P-GaN sample activated by electrochemical method than conventional annealing method. The output power of the LED is also enhanced for full structure samples with electrochemical activated P-GaN. Thus we propose an efficient method for P-GaN activation by electrochemical reaction. 30% improvement in light output is obtained by electrochemical activation method.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.7
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• pp.522-527
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• 2013

In this paper, We studied the change of surface and variation of elements on both electrodes of hydrogen generator of alkaline electrolysis in use of FE-SEM and SIMS. We used the stainless steel 316(600 ${\mu}m$) as electrode in condition of 25%KOH, $60^{\circ}C$ Temperature. The results show that the intensity of elements (C, Si, P, S, Ti, Cr, Mn, Fe, Ni, Mo) of Positive Electrode are decreased as much as about $10^1{\sim}10^3 $than the original electrode. Thickness of Positive Electrode is decreased about 40 ${\mu}m$ after chemical reaction. The negative electrode, however, shows a slight variation in the intensity of elements (C, Si, P, Fe, Ni, Mn, Mo) but Change of thickness and surface' shape of electrode show nothing after chemical reaction. The change in thickness and variation of Stainless Steel 316 cause the lifetime of electrode to be shorted. We also observed hydrogen, oxygen, potassium in both electrodes. Especially, The potassium is increased in proportional with depth of positive electrode. this means the concentration of alkali solutions is changed. and so we have to supply alkaline solution to generator in order to produce same quantity of hydrogen gas continuously. we hope that this study gives a foundation to develop the electrode for hydrogen generator of alkaline electrolysis.

• Journal of Acupuncture Research
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• v.17 no.1
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• pp.67-74
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• 2000

Hominis Placenta has been used as a medicinal stuff for a long time in Oriental Medicine. And further, aqua-acupuncture solution of Hominis Placenta has produced in South Korea recently. Bibliographical study was carried on to investigate the nature of Hominis Placenta and possible indications by aqua-acupuncture as well. The nature of Hominis Placenta is warm and its taste sweet-salty. It is non-poisonous. It has correspondence to the meridians of lung, liver and kidney. Hominis Placenta is mainly effective on recuperation of infirmity and the disease related to infirmity. Aqua-acupuncture solution of Hominis Placenta can be applied to the disease as chronic hepatitis, liver cirrhosis, asthma, pulmonary tuberculosis, sterility, insufficient lactation, degenerative change, neurasthenia and cerebrovascular disease.