• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.1 s.139
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• pp.149-156
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• 2005

The purpose of this study was to produce the high quality of electromagnetic wave shielding fabrics. In this study, we have produced polyester fabrics by electroless Ag plating. The untreated polyester was etched with $4\%$ NaOH solution added accelerant(Benzyl Dimethyl Dodecyl Ammonium Chloride) then it was catalyzed by $SnCl_2$ solution and activated by $PdCl_2$ solution. Electroless Ag plating was carried out by changing conditions such as temperature. time, weight loss rate of polyester and kind of reducing agents. The electromagnetic wave shielding effectiveness of polyester fabric by electroless Ag plating was measured by RF Impedance Analyzer and element of electromagnetic wave shielding substance was measured using Electron probe micro analyzer. The results were as follows; The plating bath using potassium sodium tartrate by reducing agent was excellent electromagnetic wave shielding effectiveness. Element of electromagnetic wave shielding substance was silver. Electromagnetic wave shielding effectiveness was shown over 64dB at the temperature of $40^{\circ}C$, treating time 30min., weight loss rate $20\%$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.5
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• pp.423-429
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• 2001

PbS, CuS and (Pb,Cu)S thin films were chemically deposited on glass from alkaline baths containing lead acetate, copper chloride, thiourea and triethanolamine. The deposition, optical, resistivity and thermal electric properties of these films were studied. PbS thin films showed a hexagonal structure and CuS thin films showed amorphous. The crystalline of (Pb,Cu)S thin films was obtained by heat treatment at 200$\^{C}$ and the deposition ratio of Pb to Cu showed 7:3. The energy gap of PbS, CuS and (Pb,Cu)S thin films were 1.7, 2.1 and 2.4 eV, respectively. Sheet resistance of PbS thin films was less affected on thermal annealing, but hose of (Pb,Cu)S and CuS thin films were more reduced about 3 orders of magnitude. All of those thin films indicated p type semiconductor in temperature ranging 30$\^{C}$ to 150$\^{C}$.

• Korean Journal of Materials Research
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• v.14 no.12
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• pp.857-862
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• 2004

Production of titanium powder directly from tantalum oxides ($TiO_2$) pellet through an electronically mediated reaction (EMR) by calciothermic reduction has been investigated. Feed material ($TiO_2\;pellet$) and reductant (Ca-Ni alloy) were charged into electronically isolated locations in a molten calcium chloride ($CaCl_2$) bath at $950^{\circ}C$. The current flow through an external circuit between the feed (cathode) and reductant (anode) locations was monitored during the reduction of $TiO_2$. The current approximately 3.2A was measured during the reaction in the external circuit connecting cathode and anode location. After the reduction experiment, pure titanium powder with low nickel content was obtained even though Ca-Ni alloy was used as a reductant. These results demonstrate that titanium powder can be produced without direct physical contact between the feed and reductant. In certain experimental conditions, pure titanium powder with approximately $99.5\;mass\%$ purity was successfully obtained.

• Journal of Surface Science and Engineering
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• v.49 no.1
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• pp.1-13
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• 2016

This review deals with one of the surface modification techniques, chemical conversion coating and particularly cerium-based conversion coatings (CeCC) as a promising substitute for chromium and phosphate conversion coating on magnesium and its alloys. The CeCCs are commonly considered environmentally friendly. The effects of surface preparation, coating thickness, bath composition, and e-paint on the corrosion behavior of CeCCs have been studied on the AZ31 magnesium alloy. This review also correlates the coating microstructural, morphological, and chemical characteristics with the processing parameters and corrosion protection. Results showed that the as-deposited coating system consists of a three layer structure (1) a nanocrystalline MgO transition layer in contact with the Mg substrate, (2) a nanocrystalline CeCC layer, and (3) an outer amorphous CeCC layer. The nanocrystalline CeCC layer thickness is a function of immersion time and cerium salt used. The overall corrosion protection was crucially dependent on the presence of coating defects. The corrosion resistance of AZ31 magnesium alloy was better for thinner CeCCs, which can be explained by the presence of fewer and smaller cracks. On the other hand, maximum corrosion protection was achieved when AZ31 magnesium samples with thin CeCCs are e-painted. The e-paint layer further restricts and hinders the movement of chloride and other aggressive ions present in the environment from reaching the magnesium surface.

• The Journal of Internal Korean Medicine
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• v.24 no.2
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• pp.260-268
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• 2003

Object : This study was undertaken to define the mechanism of GwakHyangJungGiSan-induced relaxation in rabbit common carotid artery contracted by agonists. Method : In order to investigate the effect of GwakHyangJungGiSan on rabbit's contracted vascular ring detached from common carotid artery, vascular ring intact or damaged endothelium was used for the experiment using organ bath. To analyze the mechanism of GwakHyangJungGiSan-induced relaxation, GwakHyangJungGiSan extract was infused into contracted vascular ring which had been pretreated by pretreatment of indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}-nitro-L-arginine(L-NNA)$. Result : GwakHyangJungGiSan blocks an inflow of $Ca^{2+}$ and relaxes vascular ring by the action of Nitric oxide from endothelium. Consequently when GwakHyangJungGiSan is prescribed, a rise in blood pressure by the resistance of peripheral vessel may be controlled to some extent and so it is anticipated that hypertension, a disorder of blood flow from the vascular contraction and vascular disease will be treated well.

• Journal of Radiation Industry
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• v.9 no.4
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• pp.167-170
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• 2015

Radioisotope (Nuclear) battery using $^{63}Ni$ was prepared as beta cell. The electroplated $^{63}Ni$ on Ni foil is fabricated, and beta cell and photovoltaic hybrid battery was designed to use at both day and night in space project. A Ni-plating solution is prepared by dissolving metal particles including $^{62}Ni$ and $^{63}Ni$ from neutron irradiation of ($n,{\gamma}$). Electroplating solution of a chloride bath consists on nickel ions in HCl, $H_3BO_3$, and KOH. The deposition was carried out at current density of $10mA\;cm^{-2}$. The prepared beta source was attached on a PN junction and measured I-V properties. The power output at activity of 0.07 mCi and 0.45 mCi were 0.55 pW and 2.69 nW, respectively.

• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.313-318
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• 2003

Environmental stresses, such as heat shock, alcohol and physiological salt have been shown to induce a group of protein called heat shock protein (HSPs) in various tissues. In this investigation, we studied that arsenic stress would alter contraction of isolated rat aorta and expression of heat shock protein 70 and investigated the relation between expression of HSP 70 and vascular contractility of isolated rat aorta. Rat aorta strips, mounted in organ baths were exposed to 0, 0.5, 1,2 and 4 mM arsonic for 60 min. and 1,3 and 8 hours later tested for contractile response and expression of heat shock protein 70. Contractility of rat aorta were determined by isometric transducer connected to computerized physiograph and expression of HSP 70 was characterized by western blotting, respectively. Potassium chloride (55 mM) significantly augmented vascular contractility of yat aorta by 39％ compared with the control at 8 hours but not one or three hours after treatment of 4 mM arsenic. Arsonic stress (4 mM) also increased the expression of HSP 70 in rat aorta at 8 hours but one or three hours compared with the control and HSP expressed in vascular smooth muscle cells and some expressed in endothelium cells. These results suggest that arsenic stress not only did alter the magnitude of the contractile response to high potassium chloride but also increased the expression of HSP 70 in the rat aorta.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.4
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• pp.198-206
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• 2019

This study was conducted to evaluate the vasorelaxant effect of DangGuiSu-San and SamHwangSaSim-Tang extract on contracted rabbit carotid artery. To study the effect of DangGuiSu-San and SamHwangSaSim-Tang extract on contracted rabbit carotid arterial strips, arterial strips with intact or damaged endothelium were used for experiment using organ bath. The pre-contracted arterial strips with Phenylephrine(PE) was treated with various concentrations of DangGuiSu-San and SamHwangSaSim-Tang extract(0.01, 0.03, 0.1, 0.3 and $1.0mg/m{\ell}$). To determine the mechanisms of DangGuiSu-San and SamHwangSaSim-Tang-induced vasorelaxant, DangGuiSu-San and SamHwangSaSim-Tang extract were infused into contracted arterial rings which had been pretreated by indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}$-nitro-L-arginine ($_L-NNA$), methylene blue(MB). And calcium chloride(Ca) 1 mM was infused into precontracted arterial ring induced by PE after treatment of DangGuiSu-San and SamHwangSaSim-Tang extract in $Ca^{2+}$-free krebs solution. DangGuiSu-San and SamHwangSaSim-Tang extract revealed significant relaxation on PE-induced arterial contraction. DangGuiSu-San and SamHwangSaSim-Tang extract also had an effective relaxation to the intact endothelium arterial ring. SamHwangSaSim-Tang extract on contracted rabbit carotid artery is related with NO-cGMP pathway. Pretreatment of DangGuiSu-San and SamHwangSaSim-Tang extract inhibited the contraction by influx of extracellular $Ca^{2+}$ in contracted arterial ring induced by NE. This study indicated that the relaxation effect of SamHwangSaSim-Tang extract on contracted rabbit carotid artery is related with NO-cGMP pathway. Pretreatment of DangGuiSu-San and SamHwangSaSim-Tang extract inhibited the contraction by influx of extracellular $Ca^{2+}$ in contracted arterial ring induced by NE.

• Journal of Energy Engineering
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• v.13 no.2
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• pp.93-100
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• 2004

The smear media possible to sampling and radiation detection was prepared and evaluated for the surface contamination using indirect method. The films were made by impregnating Cerium Activated Yttrium Silicate (CAYS) in a polysulfone membrane. The membranes used solution as a dimethylformamide (DMF) and methylene chloride (MC), polysulfone as a polymer matrix and CAYS as a inorganic scintillator. The proximity membranes were prepared with single- and double-layered structure. The solidified methods were immersion to the nonsolvent bath such at water and ethanol and solvent evaporation. The measurement of the photon produced by interaction with radiation and inorganic scintillator used a photomultiflier tube (PMT), amplifier, and counter. In the comparison with the low background alpha/beta counter, the counter rate using inorganic scintillator proximity membrane for the $\^$14/C surface contamination was about 50%. Also. the $^3$H counting results revealed that the prepared membranes were efficient to monitor the surface contaminated with the low energy be-ray emitter nuclides.

• The Journal of Pediatrics of Korean Medicine
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• v.12 no.1
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• pp.163-181
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• 1998

The purpose of this study was to analyze the Rhizoma on the blood pressure, heart rate and to define the mechanism of Notopterygii Rhizoma-induced relaxation in rabbit common carotid arterial contracted by agonists. Method : In order to explore the effect of Notopterygii Rhizoma on the blood pressure and heart rate, Notopterygii Rhizoma extract was injected in vein of rabbit ear. In order to investigate the effect of Notopterygii Rhizoma on norepinephrine(NE)-induced contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. To analyze the mechanism of Notopterygii Rhizoma-induced relaxation, Notopterygii Rhizoma extract infused into NE-induced contracted strips induced by agonists after treatment of methylene blue, propranolol, ouabain and it infused into serotonin, potassium chloride-induced contracted strips. Result : The blood pressure was significantly decreased by Notopterygii Rhizoma, but heart rate was insignificantly. In addition, Notopterygii Rhizoma significantly relaxed the norepinephrine, serotonin, potassium-induced contracted strips with intact endothelium or damaged endothelium. The relaxing effect of Notopterygii Rhizoma In NE-induced contracted strips with damaged endothelium by pretreatment of methylene blue, propranolol was not changed, but Ouabain was significantly decreased. Conclusion : These results were shown that Notopterygii Rhizoma affected the NE -induced contracted smooth muscle without the participation of endothelium, and demonstrated that the mechanism of NotoDtervgii Rhizoma-induced relaxation was the obstruction of receptor-operated Ca2+ channel.