• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.73-74
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• 2015

Synthesis gas such as hydrogen and carbon monoxide was produced from $CH_4/oxygen$ mixture using insulated pressurized porous media combustor. Experimentally, two cylindrical SiC foams with the different pore density were piled up in a quartz tube and fully premixed mixture was supplied in the axial direction. After stabilizing fuel-rich flame at the interface of the two foams at several pressure conditions, mole fractions of synthesis gases were measured by gas chromatography. Heat recirculation through the inner foam structure could extend the flow velocity of stable region over the laminar burning velocity. As the pressure increased, the rich flammability limit, $H_2/CO$ ratio, and module M increased.

• 한국재료학회지
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• 제23권11호
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• pp.631-637
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• 2013

Synthesis of sub-micron $2SnO{\cdot}(H_2O)$ powders by chemical reduction process was performed at room temperature as function of viscosity of methanol solution and molecular weight of PVP (polyvinylpyrrolidone). Tin(II) 2-ethylhexanoate and sodium borohydride were used as the tin precursor and the reducing agent, respectively. Simultaneous calcination and sintering processes were additionally performed by heating the $2SnO{\cdot}(H_2O)$ powders. In the synthesis of the $2SnO{\cdot}(H_2O)$ powders, it was possible to control the powder size using different combinations of the methanol solution viscosity and the PVP molecular weight. The molecular weight of PVP particularly influenced the size of the synthesized $2SnO{\cdot}(H_2O)$ powders. A holding time of 1 hr in air at $500^{\circ}C$ sufficiently transformed the $2SnO{\cdot}(H_2O)$ into $SnO_2$ phase; however, most of the PVP (molecular weight: 1,300,000) surface-capped powders decomposed and was removed after heating for 1 h at $700^{\circ}C$. Hence, heating for 1 h at $500^{\circ}C$ made a porous $SnO_2$ film containing residual PVP, whereas dense $SnO_2$ films with no significant amount of PVP formed after heating for 1 h at $700^{\circ}C$.

• Preventive Nutrition and Food Science
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• 제4권2호
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• pp.107-112
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• 1999

Effect of solvent extracts and juice supernatants from kimchis on the growth of various human cancer cells was studied, comparing with the actions on the normal cells. Inhibitory effect of kimchi extracts on[3H] thymidine incorporation n cancer cells was also investigated. The methanol extract, hexane extract and methanol soluble fraction (MSF) of 3-week fermented kimchi did not have growth inhibitory effect on Ac2F rat normal liver cells at the concentrations of 0.5~2%. However, marked decrease in the growth of AGS human gastric cancer cells was shown by the treatment of those extacts. The juice from the kimchi samples also suppressed the growth of K-562 human leukemia cells and MG-63 human osteosarcoma cells. Especially, the juice of 3-week fermented kimchi exhibited the strong growth inhibitory effect in MG-63 human osteosarcoma cells. At the photomicrographs, growth inhibition and morphological change of the cells treated with kimchi juice were observed. And the solvent extracts of 3-week fermented kimchi suppressed the growth of cancer morethan the extracts or juices from fresh and 6-week fermented kimchi. When AGS human gastric cancer cels were treated with the extracts of 3-week fermented kimchi, [3H] thymidine incorporation in the cells also decreased. These results showed that kimchi extracts and juices had growth inhibitory effects on human osteosarcoma, leukemia and gastric cancer cells, but had no toxicity to the normal cells. We suggest that kimchi might have anticancer effect in part due to inhibition of the growth and DNA synthesis of cancer cells.

• 유기물자원화
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• 제14권4호
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• pp.93-103
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• 2006

바이오가스는 유기물의 혐기소화과정에서 생기는 부산물로 열에너지와 전기에너지로 사용되어왔다. 바이오디젤생산의 반응물과 연료로 사용되고 있는 메탄올의 수요는 꾸준히 증가하고 있다. 본 총설에서는 메탄올을 메탄올로 전환하는 직접부분산화법의 최근 발전 동향을 간략한 메탄올합성의 역사와 함께 다루었으며, 산업 규모에서 주로 사용되고 있는 증기개질반응과 현재 연구단계에서 발전하고 있는 촉매산화법을 비교하였다. 이 총설에서는 바이오가스로부터 메탄올전환의 가능성이 기술적인 측면과 경제적 실용성 면에서 제시되었다.

• Archives of Pharmacal Research
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• 제27권2호
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• pp.189-193
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• 2004

Clerodendron trichotomum Thunberg Leaves (CTL) have been used for centuries in Chinese folk medicine for their anti-inflammatory properties. We have studied the anti-inflammatory effects of CTL extracts in rats, mice and in Raw 264.7 cells. 1 mg/kg solutions of the 30％ and 60％ methanol extracts of CTL were used and a 1 mg/kg of indomethacin was used as a positive anti-inflammatory standard; these were then administrated to rats. Carrageenan was injected subcutaneously to induce hind paw edema in rats. The result of carrageenan-induced rat paw oedema showed that a 1 mg/kg of the 30％, and 60％ methanol fraction of CTL and 1 mg/kg of indomethacin inhibited the hind paw edema by 19.5％, 23.0％, and 20.5％ respectively. The effect of CTL on inflammation in mice by a capillary permeability assay was examined by detecting Evans blue leakage from capillaries after the intraperitoneal injection of acetic acid, a potent inflammatory stimulus. The 60％ methanol fraction of CTL inhibited Evans blue dye leakage by 47.0％, which was 10％ higher than that of the inhibition of 1 mg/kg of indomethacin. Also, the 60％ methanol fraction of CTL suppressed the prostaglandin $E_2$ ($PGE_2$) generation in RAW 264.7 macrophage cells after treatment with lipopolysaccharide (LPS) by as much as the inhibition of 1 mg/kg of indomethacin and this led to the synthesis of $PGE_2$ by COX-2 induction. The inhibition of the carrageenan-induced rat paw oedema, vascular permeability and the $PGE_2$ generation demonstrates that the 60％ methanol fraction of CTL contains a potent anti-inflammatory activity.

• 한국균학회지
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• 제41권2호
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• pp.104-111
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• 2013

장수진흙버섯 자실체에서 메탄올을 이용해 추출한 물질의 폴리페놀 함량을 측정한 결과 4.2 mg/g으로 확인되었다. 장수진흙버섯 추출물의 B16/F10 melanoma와 NIH3T3 세포주에 대한 독성시험에서 이들 공시세포는 $200{\mu}g/mL$ 농도에서 50% 이상 생존하여 세포독성은 없는 것으로 확인되었다. DPPH 전자공여능 시험에서 장수진흙버섯 추출물의 항산화 효과는 농도 의존적으로 나타났으며 양성대조군인 BHT에 비해 우수하였다. 장수진흙버섯 추출물을 B16/F10 melanoma 세포에 150 mg/mL 처리하여 세포내 티로시나아제의 저해능을 조사한 결과, 양성대조군인 arbutin은 31.2%의 저해능을 보인 반면, 같은 농도의 장수진흙버섯 추출물 처리군의 저해능은 46.0%로 나타나 장수진흙버섯 추출물의 티로시나아제의 저해능이 양성대조군 보다 높았다. 또한 장수진흙버섯 메탄올 추출물을 B16/F10 melanoma 세포에 처리하여 멜라닌 생성량을 조사한 결과 $100{\mu}g/mL$ 농도 처리군의 멜라닌 생성량은 대조군의 31.3%로 같은 농도의 arbutin을 처리한 군의 43.9%에 비해 효과가 높았으며, 투여한 추출물의 농도가 증가함에 따라 멜라닌의 생성량은 농도 의존적으로 감소하였다. 또한 장수진흙버섯 메탄올 추출물을 분광광도계를 이용하여 자외선 영역에서의 흡수 스펙트럼을 조사한 결과 270-370 nm의 자외선 파장에서 흡광도가 높아 자외선 차단효과가 우수하였다. 따라서 장수진흙버섯의 메탄올 추출물은 피부미백이나 자외선차단 기능성 화장품으로 개발의 가능성이 높다고 사료되었다.

• Bulletin of the Korean Chemical Society
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• 제35권9호
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• pp.2813-2817
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• 2014

A new magnetic semiconductor material was synthesized to enable separation after a liquid-type photocatalysis process. Core@shell-structured $CuFeS_2@TiO_2$ magnetic nanoparticles were prepared by a combination of solvothermal and wet-impregnation methods for photocatalysis applications. The materials obtained were characterized using X-ray diffraction, transmission electron microscopy, ultraviolet-visible, photoluminescence spectroscopy, Brunauer-Emmett-Teller surface area measurements, and cyclic voltammetry. This study confirmed that the light absorption of $CuFeS_2$ was shifted significantly to the visible wavelength compared to pure $TiO_2$. Moreover, the resulting hydrogen production from the photo-splitting methanol/water solution after 10 hours was more than 4 times on the core@shell structured $CuFeS_2@TiO_2$ nanocatalyst than on either pure $TiO_2$ or $CuFeS_2$.

• Carbon letters
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• 제25권
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• pp.33-42
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• 2018

Activated carbon (AC) was modified by ammonium persulphate or nitric acid, respectively. AC and the modified materials were used as catalyst supports. The oxygen groups were introduced in the supports during the modifications. All the supports were characterized by $N_2$-physisorption, Raman, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and thermogravimetric analysis. Methanol synthesis catalysts were prepared through wet impregnation of copper nitrate and zinc nitrate on the supports followed by thermal decomposition. These catalysts were measured by the means of $N_2$-physisorption, X-ray diffraction, XPS, temperature programmed reduction and TEM tests. The catalytic performances of the prepared catalysts were compared with a commercial catalyst (CZA) in this work. The results showed that the methanol production rate of AC-CZ ($23mmol-CH_3OH/(g-Cu{\cdot}h)$) was higher, on Cu loading basis, than that of CZA ($9mmol-CH_3OH/(g-Cu{\cdot}h)$). We also found that the modification methods produced strong metal-support interactions leading to poor catalytic performance. AC without any modification can prompt the catalytic performance of the resulted catalyst.

• 한국재료학회지
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• 제9권8호
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• pp.798-803
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• 1999

본 연구는 SAPO-34 결정골격에 도입된 Fe(III)의 메탄올 전환성능에 미치는 영향에 중점을 두었다. 신속결정화법에 의해 높은 결정화도, 좁은 입자 분포도를 갖는 결정(FeAPSO-34; Si/Fe=40,20,5)들이 얻어졌으며, SRD와 SEM의 결과로부터, 골격에 도입된 Fe양이 증가할수록 결정화도는 감소하고, 그 입자크기도 아울러 감소함이 관찰되었다. 한편, 이들의 산성도는 골격에 도입된 Fe양이 증가할수록 감소하였고, 그 결과 메탄올 전환에 있어서 에틸렌의 선택성이 향상되는 결과를 가져왔다.

• 한국전기전자재료학회논문지
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• 제25권10호
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• pp.824-829
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• 2012

Zn wires have been electrically exploded in methanol or distilled water using the pulsed power technologies. The nanopowders produced by the explosions have been observed by using SEM and TEM, and analyzed its phase by using EDS and XRD. The nanopowders produced in distilled water showed ZnO phase only. On the other hands, the nanopowder produced in methanol showed mixed phases with Zn and ZnO. The HR-TEM images of the nanopowders produced in methanol showed that the some particles have been coated with carbon like materials. It is considered that the carbon coatings could be depended on the positions of the particles during the plasma state formed by explosion.