• 대한한방내과학회지
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• 제26권1호
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• pp.199-212
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• 2005

Objective : Airway inflammation is now regarded as a defining feature of asthma. The importance of eosinophits in the airway inflammation of asthma patients is widely recognized, and eosinophils mobilization in the respiratory epithelium is activated by chemoattractants and cytokines. This study was designed to examine the extent of the ability of Moutan Cortex Radicis to inhibit eosinophil chemotaxis of pulmonary epithelium after allergic stimulation. Material and Methods : Water extracts of Moutan Cortex Radicis and pulmonary epithelial cell lines A549(human type II-like epithelial cells) and human eosinophils were used. Cytotoxic effects of Moutan Cortex Radicis were estimated via MTS assay, and the effects of Moutan Cortex Radicis on chemokines from prestimulated A549 cells were estimated by sandwich ELISA and RT-PCR. Chemotaxis assay on prestimulated eosinophils treated with Moutan Cortex Radicis. was conducted Result : In this study we demonstrated that $TNF-{\alpha}$ and IL-4, $IL-1{\beta}$ induced the accumulation of chemokines' mRNA in the pulmonary epithelial cell lines A549 in a dose-dependent manner. Chemokines of eotaxin, ICAM-1, YCAM-1, IL-8, IL-16 were inhibited by Moutan Cortex Radicis in a dose dependent manner, but RANTES showed no inhibition due to Moutan Cortex Radicis. Eosinophil migration was inhibited at high concentrations of Moutan Cortex Radicis. Conculusion : These findings are indicative of supression of chemokines accomplished by Moutan Cortex Radicis treatment, demonstrating the potential therapeutic value of Moutan Cortex Radicis for treating diseases such as asthma.

• 공업화학
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• 제7권3호
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• pp.410-415
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• 1996

여러 가지 중수생산 공정중에서 백금촉매를 이용한 수소-중수소 동위원소 교환반응에 의해 중수를 생산하는 공정이 가장 효율적인 것으로 알려져 있다. 본 연구에서는 수소동위원소 교환반응에 이용될 수 있는 소수성 백금촉매를 개발하기 위하여, 담체로서 실리카라이트를 합성하였으며, 합성된 실리카라이트가 활성탄이나 ZSM-5보다 더 강한 소수성을 가지는 것을 보였다. 또한, 일반적인 함침법과 이온교환법을 이용하여 백금을 담지시켰으며, 여러 가지 방법으로 처리하여 제조한 백금담지 실리카라이트 촉매의 백금분산도를 수소흡착법을 이용하여 측정하였다. 함침법에 의해 제조된 촉매의 백금분산도는 매우 낮았으며, 이온교환법에의해 제조된 촉매는 백금담지량은 적으나 분산도는 높음을 확인하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제9권3호
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• pp.120-128
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• 2005

콘크리트용 혼화재료로 고로슬래그미분말은 경제적, 환경적 이점뿐만 아니라, 고강도, 내해수성, 내화학성과 같은 성능개선의 효과도 있다. 고로슬래그미분말이 콘크리트용 재료로서 아주 유용한 자원임에도 불구하고, 초기 강도의 저하로 인한 거푸집의 해체 및 순환의 문제로 공사기간이 지연되어 공사비의 증가 등의 단점이 있다. 따라서 본 연구에서는 고로슬래그미분말 혼합 모르타르의 초기 강도의 증진을 위하여, 다양한 알칼리 자극제를 혼합 사용하여, 모르타르의 유동성 및 압축강도 특성을 평가하였다. 또한 알칼리 자극제의 혼합에 따른 수화 반응 성상을 알아보기 위하여, XRD 분석, 미소수화열 및 $Ca(OH)_2$를 정량하였다. 실험결과 유동성과 응결시간에 대한 단점을 고로슬래그미분말로 보완하고, 적당한 알칼리 자극제의 선택과 첨가량을 조절하여 사용한다면, 고로슬래그미분말을 콘크리트에 사용하여도 초기 강도 저하 없이 사용가능할 것으로 판단된다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권3호
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• pp.205-215
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• 2002

The purpose of this study was to evaluate the tissue response in various bone grafting materials, especially xenogenous bone materials in vivo, compare of bone formation capacity of various bone grafting materials on rat skull defects and evaluate the effect of Hyaluronic acid on healing of human Demineralized Freezed Dried Bone allogenous graft (DFDBA) materials in rat calvarial defects. 30 Sprague-Dawly rats were divided into 4 groups. $7{\times}7mm$ size bony defect were artificially prepared in the calvaria (both parietal bone) of all 30 rats and follwed group grafting of autogenous bone graft on right side and allogenic DFDBA on left side bone graft (rat DFDB) in 15 control group, but in 15 experimental group, xenograft (human DFDB) on left side, hyaluronic acid treated with xenograft on right side. Sequential sacrifices was performed at 1, 2, 4, 6, 8 weeks of experiment. These specimens were stained with H&E and MT stain, and then histologic analysis under light microscope was carried out. There were inflammatory reaction in all graft material during early stage. Autogenous and Allogenous DFDBA graft group observed inflammatory reaction at 1 week. Xenograft group persistant inflammatory reaction until 4 weeks, but in HA treated xenograft group inflammatory reaction was decreased at 2 weeks. Osteoblastic activity in control group was begun at 2 week, xenograft group was delayed at 6 weeks, however HA treated xenograft group was begun at 4 weeks. At 2 week, mild osteoclastic activity were observed in all xenograft group not in concerned to HA, but there was no difference each group after 4 weeks. There are most activated angiogenesis around graft mateirals in xenograft group at 2 weeks, but in HA treated xenograft group, decreased angiogenesis was observed at same time. Bone formation and bone maturation of xenograft group, there was no difference in HA treatment, was less than control group. Fibrosis around xenograft materials were observed until 6 weeks, there was no difference between xenograft and HA treated groups.

• 콘크리트학회논문집
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• 제24권2호
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• pp.121-127
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• 2012

지금까지 연구된 고인성 섬유 복합체의 주요 결합재는 시멘트이다. 이 연구의 목적은 시멘트를 전혀 사용하지 않은 고로슬래그 기반 알칼리 활성 모르타르와 PVA(polyvinyl alcohol) 섬유를 이용하여 고인성을 나타내는 복합체에 대한 가능성을 검토하는 것이다. 이를 위하여 알칼리 활성화제 종류에 따라 균일한 섬유 분산성을 확보하면서 섬유 혼합을 용이하게 하기 위한 적절한 모르타르의 유동성 및 점성을 갖는 두 가지 배합을 결정하였고, 복합체의 기본적인 성능을 평가하기 위하여 슬럼프 플로, 압축강도, 일축인장, 휨 실험을 수행하였다. 실험 결과 두 가지 배합의 슬럼프 플로는 평균 465 mm로 나타났고, 약 2% 정도의 인장 변형 성능과 다중 미세균열을 나타내는 것을 확인하였다. 이를 통하여 시멘트를 전혀 사용하지 않고도 변형률 경화 거동에 의한 고인성을 나타내는 섬유 복합체의 개발 가능성을 입증하였다.

• 한국수소및신에너지학회논문집
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• 제22권5호
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• pp.706-713
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• 2011

The effects of silica-alumina type catalysts addition on the thermal decomposition of ethylene vinyl acetate (EVA) resin have been studied in a thermal analyzer (TGA, DSC) and a small batch reactor. The silica-alumina type compounds tested were kaolinite, bentonite, perlite, activated clay and clay. As the results of TGA experiments, pyrolysis starting temperature for EVA resin had the 1st pyrolysis temperature range of 300~$400^{\circ}C$ and the 2nd pyrolysis temperature range of 425~$525^{\circ}C$. The silica-alumina type catalysts did not affect the pyrolysis rate in EVA pyrolysis reaction. In the DSC experiments, addition of kaolinite and bentonite catalysts reduced the heat of fusion and heat of 2nd pyrolysis reaction. In the batch system experiments, the mixing of silica-alumina type catalysts enhanced the yield of fuel oil, and affected to the distribution of carbon numbers. In the silica-alumina type inorganic material used in this experiments, bentonite was the most effective from the pyrolysis heat, yields, and the characteristics of fuel oil.

• Advances in Energy Research
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• 제5권3호
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• pp.219-226
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• 2017

Electrochemical double layer capacitors (EDLCs) have received a tremendous interest due to their suitability for diverse applications. They have been fabricated using different carbon based electrodes including activated carbons, single walled/multi walled carbon nano tubes. But, graphite which is one of the natural resources in Sri Lanka has not been given a considerable attention towards using for EDLCs though it is a famous carbon material. On the other hand, EDLCs are well reported with various liquid electrolytes which are associated with numerous drawbacks. Gel polymer electrolytes (GPE) are well known alternative for liquid electrolytes. In this paper, it is reported about an EDLC fabricated with a nano composite polyethylene oxide based GPE and two Sri Lankan graphite based electrodes. The composition of the GPE was [{(10PEO: $NaClO_4$) molar ratio}: 75wt.% PC] : 5 wt.% $TiO_2$. GPE was prepared using the solvent casting method. Two graphite electrodes were prepared by mixing 85% graphite and 15% polyvinylidenefluoride (PVdF) in acetone and casting n fluorine doped tin oxide glass plates. GPE film was sandwiched in between the two graphite electrodes. A non faradaic charge discharge mechanism was observed from the Cyclic Voltammetry study. GPE was stable in the potential windows from (-0.8 V-0.8 V) to (-1.5 V-1.5 V). By increasing the width of the potential window, single electrode specific capacity increased. Impedance plots confirmed the capacitive behavior at low frequency region. Galvanostatic charge discharge test yielded an average discharge capacity of $0.60Fg^{-1}$.

• Journal of Periodontal and Implant Science
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• 제38권3호
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• pp.543-550
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• 2008

Purpose: The purpose of this study was to investigate induction of cytokine expression in human gingival fibroblasts (HGFs) by whole cell and the components of T. forsythia. Material and Methods: After HGFs were treated with lipopolysaccharide (LPS), membrane protein isolated from T. forsythia or culture media of T. forsythia, the induction of interleukin (IL)-1, IL-6 and IL-8 was examined with real-time PCR and ELISA. Their induction ability of cytokines was compared with whole bacteria. Result: The expression of IL-6 and IL-8 was significantly induced in HGFs by whole bacteria and membrane protein. The expression of IL-$1{\beta}$ was induced by membrane protein of T. forsythia, not by whole bacteria. LPS and condition media of T. forsythia slightly activated HGFs. Conclusion: The membrane protein of T. forsythia could be one of virulence factors.

• 한국환경과학회지
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• 제25권5호
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• pp.645-654
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• 2016

For the purpose of reuse the wasted by-products from the skate process to the health functional food or medicinal material, chondroitin sulfate was extracted from the skate cartilage with the method of hydrolysis with protease enzyme, and the contents of chondroitin sulfate and hydrolyzed protein were measured qualitatively and quantitatively. The effects of chondroitin sulfate on body weight or liver weight changes, hepatotoxicity elimination and anti-inflammatory actions were measured from in vivo test with feed-treated mice. From the hydrolytic extraction of skate cartilage with the mixture of 1% alcalase and 1% protease for 4 hours, the extraction yield of chondroitin sulfate was about 32.55%. The content and molecular weight of chondroitin sulfate was 26.63% and $2.85{\times}10^5Da$., respectively and the content ratio of chondroitin sulfate to protein was measured to 1 to 2.76 with gel permeation chromatography. For the odor component, trimethylamine decreased about 30% but almost not ammonia from chondroitin sulfate with the treatment of activated carbon. From the feeding chondroitin sulfate to mice, the control effect of body and liver weights decrease was measured, anti-inflammatory action and hepatotoxicity elimination action were also measured. From these results, process operation conditions for manufacturing of chondroitin sulfate were suggested.

• 한국세라믹학회지
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• 제40권3호
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• pp.241-248
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• 2003

고체산화물 연료전지용 음극소재로 사용되는 다공성 NiO-YSZ 소재의 강도를 향상시키기 위하여 $Y_2$O$_3$첨가제의 양 및 기공전구체로 첨가되는 탄소첨가제의 종류를 변화시켰으며, 이에 따른 기계적 강도와 기공율, 전기전도도를 측정하였다. $Y_2$O$_3$첨가제의 양은 8 mol%와 10 mo1%로 각각 변화시켰으며, 기공전구체는 활성탄과 카본블랙의 영향을 고찰하였다. 그 결과 카본블랙을 기공전구체로 사용하였을 경우 활성탄을 사용한 경우에 비해 기계적 강도가 크게 향상되었으며, 상대적으로 고온의 소결온도에서 제조된 10 mo1%의 $Y_2$O$_3$가 첨가된 NiO-YSZ 음극소재가, 8 mol%가 첨가된 소재에 비하여 상대적으로 우수한 강도를 나타내었다. 10 mo1%의 $Y_2$O$_3$와 카본블랙이 첨가된 음극소재는 전기전도도 값에 있어서도 $700^{\circ}C$~100$0^{\circ}C$의 온도범위에서 $10^2$~$10^3$S/cm의 양호한 값을 나타내는 것으로 평가되었다.