• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.129-130
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• 1998

In this paper, We designed the ECG-NIBP-$SpO_2$ patient monitor. This production can measure Electrocardiograph, Heart Rate, Noninvasive Blood Pressure, and Oxygen Saturation for Noninvasive Mehod and can display each information. These informations were implemented by the electrodes of ECG part, the cuff of NIBP module and the finger probe with light sensor of $SpO_2$ without injection of needle or catheter. In addition, We developed a new analysis algorithm and measurement technique for NIBP and $SpO_2$ to observe patient's conditions correctly.

• Journal of the Korean Ceramic Society
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• v.24 no.1
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• pp.17-22
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• 1987

This study is to detect the synthetic condition for the formation of Sr-Ferrite(SrFe12O19) by hydrothermally reaction. Mixed suspension of SrCl26H2O and FeCl3 6H2O were fixed on pH and were subjected to autoclavings at various temperature(150∼300$^{\circ}C$), reaction time(2hrs.∼48hrs.). The Sr-Ferrite powders were synthesized at 150$^{\circ}C$ for 36hrs, 200$^{\circ}C$ for 4hrs and 250$^{\circ}C$ for 2hrs. Synthesized powders were increased particle sizes at longer reaction time and higher reaction temperature. It has hexagonal ferrite M-type structure and has high purity of SrO.5.6 Fe2O3 composition.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.317-317
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• 2012

본 연구는 전착법으로 형성된 $Cu_2O$ 박막의 광특성 변화를 고찰한 것이다. 0.3M $CuSO_4$과 4M Lactic acid에 4M NaOH로 전해액의 pH를 조절하여 $Cu_2O$ 박막의 결정성 및 극성을 조절하였다. $Cu_2O$ 박막의 결정성 및 극성에 따른 광특성을 고찰한 결과, 무극성인 (111)면에서 광특성이 우수함을 확인하였다. 하지만, 측정시간의 증가에 따라 표면에 Cu 금속이 형성되어 광전류가 감소함을 확인 할 수 있었다.

• Journal of the Korean Vacuum Society
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• v.19 no.4
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• pp.275-280
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• 2010

The influence of $O_2$-plasma treatment on $H_2$ post-treated BZO (ZnO:B) thin film using MOCVD (Metal-Organic Chemical Vapor Deposition) are investigated. An $O_2$-plasma treatment of the $H_2$ post-treated BZO thin films resulted in XRD peak of (100), (101) and (110). Also, electrical properties resulted in an increase in sheet resistance and work function. The weighted optical transmittance and haze at 300~1,100 nm of BZO thin films with $O_2$-plasma treatment on the $H_2$ post-treatment show approximately 86% and 15%, respectively.

• Resources Recycling
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• v.31 no.4
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• pp.49-55
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• 2022

In this study, the heavy metal ions (of Pb, Cd, Cr, and Hg) in wastewater were removed using a spent Li₂O-Al₂O₃-SiO₂-based crystallized glass previously used as an induction top plate material. Changes in the removal efficiency of heavy metals according to different reaction parameters, such as the amount of zeolite used as a heavy-metal adsorbent, adsorption time, initial concentration of the heavy metals, and pH of the initial solution, were investigated. As the amount of zeolite added increased, the heavy-metal removal efficiency also increased. Adsorption time had a considerable influence on adsorption characteristics, and the removal efficiency of all heavy metals increased with increasing adsorption time. In the case of Cd, the removal efficiency was greatly improved depending on the adsorption time. The initial concentration of the heavy-metal solution did not affect the removal efficiency; however, the initial pH of the heavy-metal solution affected the removal efficiency. More specifically, the removal efficiency of Cd increased while that of Pb and Cr decreased with increasing pH. The adsorption characteristics of Hg were not significantly affected by pH.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1466-1468
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• 1994

In this paper Dielectric and strain properties of (1-x-y)PMN-yPT-xST Ceramics have been investigated as a function of the amount of $SrTiO_3(ST)$. The $SrTiO_3$ content is ranged from 0.01-0.06(wt%). As the amount of ST is increased, dielectric constant has a maximum value at 0.05 mol composition. The Curie temperature is decreased linearly with increasing ST composition and Polarization properties have been investigated. Coercive field and ramnant polarization has a maximum value at 0.01mol composition.

• The Journal of Korean Medicine
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• v.25 no.3
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• pp.149-159
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• 2004

Backgrounds & Objectives : The water extract of Gyungokgo (GOG) has traditionally been used for treatment of general weakness and hemoptysis in oriental medicine. However, little is known about the mechanism by which the water extract of GOG rescues cells from these damages. This study was designed to investigate the protective mechanisms of GOG on H2O2­induced cell death in H9c2 cardiomyoblasts. Methods : In this study, we used H9c2 cells. Cells were treated with oxidative stress in the absence and presence of 1000㎍/ml GOG for 12hrs. Cells were treated with various concentrations of GOG for 12hrs. Cell viability was measured by MTT assay. Oxidative stress, which markedly decreased the viability of H9c2 cells, was characterized by apparent apoptotic features such as chromatin condensation as well as fragmentation of genomic DNA and nuclei. Results : GOG significantly reduced H₂O₂-induced cell death and apoptotic characteristics. The cotreatment of GOG and H₂O₂ in H9c2 cells also induced the phosphorylation of ERKs in a time-dependent manner. Moreover, PD098059, a MEK1 (upstream activator of ERK) inhibitor attenuated the protective effect of GOG on H₂O₂-induced cytotoxicity in H9c2 cardiomyoblast cells. Conclusions : These results suggest that MEK/ERK pathways play important roles in the protective effects of GOG in H9c2 cells. Taken together, they suggest that the protective effects of the water extracts of GOG against oxidative damages may be mediated by the regulation of HO-1, Fas/FasL and Bcl-XS proteins.

• Journal of the Korean Chemical Society
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• v.13 no.2
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• pp.149-156
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• 1969

$NaAl(OH)_2CO_3$was synthesized using colloidal earth (Allophane) as the starting material and some of its were studied in detail. It was found that Dawsonite was formed in the pH range (pH 12.5~12.0) that the concentration of $HCO_3^-$ was just begun to increase and the presence of $HCO_3^-$ in the product was clarified from the infrared absorption spectrum. The chemical formular of Dawsonite was therefore presumed as $NaAlO (OH) HCO_3$. From toahhe results of X-ray powder diffraction, both peaks at 5.7 $\AA$ and 2.8 $\AA$ were observed, and fibrous crystalline structure was observed from electron micrograph and also found from the microscopic electron diffraction at 5.7 $\AA.$ Therefore the fibrous axis was considered as =Al=O2=Al=O2=Al=(*image) direction. True specific gravity of Dawsonite was 2.44 and its porosity was 91.4%. It was practically insoluble in water, but decomposed in the boiling water to form Pseudo Boehmite. Stable pH range of Dawsonite was about 4.5~11.5. From the results of D.T.A. and T.G.A., it was observed that $CO_2$was liberated at $350^{\circ}C$, and $H_2O$ at $650^{\circ}C$, and converted into strongly hygroscopic $NaAlO_2$, which was easily decomposed in water into $\beta-Al(OH)_3(Bayerite)$ and NaOH.

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.723-726
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• 2010

An efficient and simplified protocol for $NaHSO_4/SiO_2$ catalyzed solvent-free synthesis of $\beta$-enaminone and 2-methylquinolin-4(1H)-one derivatives under microwave irradiation is described. A series of functionalized derivatives have been synthesized in shorter reaction times with moderate to good yields. The use of milder catalyst in non-conventional method offers significant advantages over conventional methods, such as higher selectivities, simplicity, solvent-free reaction and non-environmental polluting conditions.

• Journal of Power System Engineering
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• v.20 no.5
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• pp.86-91
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• 2016

This paper is concerned chiefly with the method of porous foam manufacture using basalt stone powder sludge. The hydrogen peroxide($H_2O_2$) of bloating agent has lots of problems to manufacture porous lightweight aggregate due to fast reaction rate with cement or calcium hydroxide($Ca(OH)_2$). The $H_2O_2$ injecting method using nozzle for manufacturing porous lightweight aggregate is proposed, in this study. This method is to inject $H_2O_2$ at the pressure of 10 MPa on upper side of slurry mixing materials such as stone powder sludge and quick-lime(CaO) by injector. The specimen was dried in furnace at $100^{\circ}C$ for 1 hour and cured at ambient temperature for 30 days. We analyzed the characteristics including specific gravity and water absorption. The experiments were found that the porous foam has low specific gravity, high water absorption and uniform distribution of porous more than manufactured foam by general bloating methods.