• 한국전기전자재료학회논문지
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• 제13권10호
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• pp.865-870
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• 2000

In this paper, catalytic combustible gas sensor was fabricated and tested under flammable gases such as CH$_4$and $C_4$H$_{10}$by using Pt coil as a heater and/or temperature sensing element. Fine $Al_2$O$_3$powder was used for a bead and Pt, Pd noble metal powder for a catalyst. Resistance variation of Pt wire was traced by the changes of the gas concentrations in a chamber. Output voltage was then monitored to obtain the gas concentration from the resistance variation. In this experiment, MgO was used to protect cracks in the based and TiO$_2$to increase the sensitivity of the sensors. Water glass was also added to enhance the selectivity to the combustible gases.s.

• 조명전기설비학회논문지
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• 제20권7호
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• pp.58-64
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• 2006

최근 탈취, 탈색, 정수처리 및 배연가스의 정화에 많이 이용되고 있는 오존의 효과적인 발생에 많은 관심이 모아지고 있다. 전기 방전에 의한 오존 발생 방법 중 유전체 배리어 방전이 보다 낮은 전력을 소모하며, 또한 저전압 동작이 가능하여 가장 효과적인 것으로 생각되고 있다. 본 연구에서는 오존발생농도 및 에너지효율을 개선하기 위하여 알루미나 유전체 및 알루미나 유전체와 알루미나 비드를 충진한 무성방전관을 제작하여 무성방전특성을 연구하였다. 또한 오존발생특성을 무성방전특성과 연관하여 논하였으며, 특히 방전시 유전체에 축적되는 벽전하 및 소비전력특성의 관점에서 논하였다. 결과, 비드를 가진 방전관의 경우 축적되는 벽전하량은 비드가 없는 방전관에 비하여 약 2.5배 정도였으며, 발생되는 오존농도 및 에너지 수율 또한 개선되었다.

• 대한한의학회지
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• 제33권4호
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• pp.42-49
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• 2012

Objectives: The purpose of this study was to investigate effects of Red Ginseng-Ejung-tang Water Extract (ER) on cytokine production in RAW 264.7 mouse macrophages stimulated by lipopolysaccharide (LPS). Methods: Levels of various cytokines such as interleukin (IL)-6, IL-10, IL-2, IL-12p70, vascular endothelial growth factor (VEGF), monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-2, keratinocyte-derived chemokine (KC), tumor necrosis factor (TNF)-alpha, granulocyte macrophage colony-stimulating factor (GM-CSF) were measured by high-throughput multiplex bead array cytokine assay based on xMAP (multi-analyte profiling beads) technology. Results: ER significantly decreased levels of IL-6, IL-10, IL-2, IL-12p70, VEGF, and MCP-1 for 24 hrs incubation at the concentrations of 25, 50, and $100{\mu}g/mL$ in LPS-induced RAW 264.7 cells (P < 0.05). But ER did not exert significant effects on production of MIP-2, KC, TNF-${\alpha}$, and GM-CSF in LPS-induced RAW 264.7 cells. Conclusions: These results suggest that ER has an anti-inflammatory property related with its inhibition of cytokine production in LPS-induced macrophages.

• 대한본초학회지
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• 제28권6호
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• pp.129-133
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• 2013

Objectives : The purpose of this study was to investigate the effects of Angelicae acutilobae Radix Water Extract (AA) on the production of cytokines in RAW 264.7 cell stimulated with lipopolysaccharide (LPS). Method : RAW 264.7 cells were cotreated with AA (50 and $100{\mu}g/mL$) and lipopolysaccharide (LPS; $1{\mu}g/mL$) for 24 hours. After 24 hours treatment, using bead-based multiplex cytokine assay, concentrations of various cytokines such as interleukin(IL)-6, tumor necrosis factor-alpha(TNF-${\alpha}$) granulocyte colony-stimulating factor(G-CSF), granulocyte macrophage colony-stimulating factor(GM-CSF), and macrophage inflammatory protein(MIP)-$1{\alpha}$ were measured. Result : AA significantly inhibited LPS-induced production of IL-6 and MIP-$1{\alpha}$ from LPS-stimulated RAW 264.7 cells at the concentration of $50{\mu}g/mL$. AA significantly inhibited LPS-induced production of TNF-${\alpha}$ from LPS-stimulated RAW 264.7 cells at the concentration of $100{\mu}g/mL$. AA significantly inhibited LPS-induced production of G-CSF and GM-CSF in RAW 264.7 cells at the concentrations of 50 and $100{\mu}g/mL$. Conclusion : These results suggest that AA has anti-inflammatory effect related with its inhibition of proinflammatory cytokines such as IL-6, TNF-${\alpha}$, G-CSF, GM-CSF, and MIP-$1{\alpha}$ in LPS-induced macrophages.

• 한국물환경학회지
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• 제38권4호
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• pp.171-176
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• 2022

Recently, an autotrophic single-stage nitrogen removal (ASSNR) process based on the anaerobic ammonium oxidation (ANAMMOX) reaction has been proven as an economical ammonia treatment. It is highly evident that double-layered gel beads are a promising alternative to the natural biofilm for ASSNR because of the high mechanical strength of poly(vinyl alcohol) (PVA)/alginate structure and efficient protection of ANAMMOX bacteria from dissolved oxygen (DO) due to the thick outer layer. However, the thick outer layer results in severe mass transport limitation and consequent lowered bacterial activity. Therefore, the effects of the thickness of the outer layer on the overall reaction rate were tested in the biofilm model using AQUASIM for ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB) and ANAMMOX bacteria. A thickness of 0.5~1.0 mm is preferred for the maximum total nitrogen (TN) removal. In addition, a DO of 0.5 mg/L resulted in the best total nitrogen removal. A higher DO induces NOB activity and consequent lower TN removal efficiency. The optimal density of AO B and NO B density was 1~10% for a 10% ANAMMOX bacterial in the double-layered PVA/alginate gel beads. The real effects of operating parameters of the thickness of the outer layer, DO and concentrations of biomass balance should be intensively investigated in the controlled experiments in batch and continuous modes.

• 한국세라믹학회지
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• 제54권1호
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• pp.49-54
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• 2017

In this study, based on hydrolysis and condensation via $St{\ddot{o}}ber$ process of sol-gel method, synthesis of mono-dispersed silica nanoparticles was carried out with hydrophilic solvent. This operation was expected to be a more simplified process than that with organic solvent. Based on the sol-gel method, which involves simply controlling the particle size, the particle size of the synthesized silica specimens were ranged from 30 to 300 nm by controlling the composition of tetraethylorthosilicate (TEOS), DI water and ammonia solution, and by varying the stirring speeds while maintaining a fixed amount of ethanol. Increasing the content of DI water and decreasing the content of ammonia caused the particle size to decrease, while controlling the stirring speed at a high level of RPMs enabled a decrease of the particle size. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were utilized to investigate the success factors for synthesizing process; Field emission scanning electron microscopy (FE-SEM) was used to study the effects of the size and morphology of the synthesized particles. To analyze the dispersion properties, zeta potential and particle size distribution (PSD) analyses were utilized.

• 대한본초학회지
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• 제28권5호
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• pp.113-119
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• 2013

Objectives : The purpose of this study was to investigate the effects of Angelicae Gigantis Radix Water Extract(AG) on the production of proinflammatory mediators in RAW 264.7 cells stimulated with lipopolysaccharide(LPS). Method : RAW 264.7 cells were cotreated with AG(50 and 100 ug/mL) and lipopolysaccharide(LPS; 1 ug/mL) for 24 hours. After 24 hour treatment, using Bead-based multiplex cytokine assay, concentrations of various cytokines such as interleukin(IL)-6, IL-$1{\beta}$, IL-10, tumor necrosis factor-alpha(TNF-${\alpha}$), granulocyte colony-stimulating factor(G-CSF), granulocyte macrophage colony-stimulating factor(GM-CSF), interferon inducible protein-10(IP-10), leukemia inhibitory factor(LIF), lipopolysaccharide-induced chemokine(LIX), monocyte chemoattractant protein-1(MCP-1), macrophage colony-stimulating factor(M-CSF), macrophage inflammatory protein(MIP)-$1{\alpha}$, MIP-$1{\beta}$, MIP-2, Regulated on Activation, Normal T cell Expressed and Secreted(RANTES) and vascular endothelial growth factor(VEGF) were measured. Result : AG significantly inhibited LPS-induced production of TNF-${\alpha}$, MIP-$1{\alpha}$, G-CSF, RANTES, IL-10, and M-CSF from LPS-stimulated RAW 264.7 cells at the concentrations of 50 and 100 ug/mL. AG significantly inhibited LPS-induced production of MIP-$1{\beta}$, MIP-2, GM-CSF, and IL-6 from LPS-stimulated RAW 264.7 cells at the concentrations of 50 ug/mL. AG significantly inhibited LPS-induced production of VEGF from LPS-stimulated RAW 264.7 cells at the concentrations of 100 ug/mL. But AG did not show any significant effect on the production of MCP-1, LIF, LIX, IP-10 and IL-$1{\beta}$ from LPS-induced RAW 264.7 cells. Conclusion : These results suggest that AG has anti-inflammatory effect related with its inhibition of proinflammatory mediators such as TNF-${\alpha}$, MIP-$1{\alpha}$, G-CSF, RANTES, IL-10, MIP-$1{\beta}$, MIP-2, GM-CSF, IL-6, VEGF and M-CSF in LPS-induced macrophages.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.566-569
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• 2005

tyrosinase 저해 활성 실험 결과 1.2%(w/v) 이상의 농도에서 70% 이상의 저해를 나타내 색소침착에 대한 기능성 화장품 원료로 사용이 가능할 것으로 보이며, ACE 저해 활성 실험에서 1.5% 농도에서 60% 가량의 저해활성을 보여 혈관 변형 치료 및 예방에 효과가 있을 것으로 기대된다. UV 흡수능에서는 UV-B, UV-C의 영역에서 흡수 경향을 나타내며 자외선 차단제의 원료로 사용이 가능할 것으로 기대되며, 또한 bead 형성능을 가지고 있어 약물전달체로서 이용 가능성이 기대된다.

• 대한본초학회지
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• 제25권3호
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• pp.27-34
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• 2010

Objectives : The purpose of this study is to investigate the effect of Fermented Houttuyniae Herba Water Extract (HL) on production of proinflammatory mediators in mouse macrophage RAW 264.7 cells. Methods : Cell viabilities were measured by MTT assay. Effect of HL on nitric oxide (NO) production from RAW 264.7 cells was accessed by Griess reagent assay. Effect of HL on productions of inflammatory cytokines such as interleukine (IL)-17, Interferon $\gamma$-inducible protein (IP)-10, Eotaxin, IL-5, Monocyte Chemotactic Protein-3 (MCP-3), and IL-13 in LPS-induced RAW 264.7 cells was accessed by a multiplex bead array assay based on xMAP technology. Results : The results of the experiment are as follows. 1. Incubation with HL for 24 hours showed significant increase in cell viability of RAW 264.7 mouse macrophages (P < 0.05). 2. HL showed to inhibit NO production from RAW 264.7 cells at the concentrations of 25 and 50 ug/mL significantly (P < 0.05). 3. HL inhibited significantly NO production in LPS-induced RAW 264.7 cells at the concentrations of 25, 50, 100 and 200 ug/mL (P < 0.05). 4. HL inhibited significantly IL-17, IP-10 and Eotaxin in LPS-induced RAW 264.7 cells at the concentrations of 25, 50, 100 and 200 ug/mL (P < 0.05). Conclusions : These results suggest that HL has anti-inflammatory moiety related with its inhibition of NO, IL-17, IP-10, and Eotaxin in macrophages.

• 동의생리병리학회지
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• 제27권6호
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• pp.738-744
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• 2013

The purpose of this study is to investigate effects of White Ginseng-Ejung-tang water extract (EJ) on production of various cytokines such as interleukin (IL)-2, IL-5, IL-6, IL-10, IL-12p70, macrophage inflammatory protein (MIP)-2, vascular endothelial growth factor (VEGF), keratinocyte-derived chemokine(KC), tumor necrosis factor (TNF)-${\alpha}$, and granulocyte macrophage colony-stimulating factor (GM-CSF) in RAW 264.7 mouse macrophages stimulated by lipopolysaccharide (LPS). Levels of cytokines were measured by High-throughput multiplex bead array cytokine assay based on xMAP (multi-analyte profiling beads) technology. EJ significantly decreased levels of IL-2, IL-12p70, IL-5, MIP-2 for 24 h incubation at the concentrations of 25, 50, and 100 ${\mu}g/mL$ in LPS-induced RAW 264.7 (P < 0.05). EJ significantly decreased levels of IL-6 at the concentrations of 50 and 100 ${\mu}g/mL$ (P < 0.05). EJ significantly decreased levels of IL-10 and VEGF at the concentrations of 25 and 100 ${\mu}g/mL$ (P < 0.05). EJ significantly decreased levels of KC at the concentrations of 100 ${\mu}g/mL$ (P < 0.05). EJ did not show any significant effect on TNF-${\alpha}$ and GM-CSF production. These results suggest that EJ has anti-inflammtory property related with its inhibition of IL-2, IL-5, IL-6, IL-10, IL-12p70, MIP-2, VEGF, and KC production in LPS-induced macrophages.