• 대한한의학회지
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• 제18권2호
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• pp.15-32
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• 1997

This study was undertaken to define the mechanism of Siegesbeckiae Herba-induced relaxation in rabbit common carotid artery contracted by agonists. In order to investigate the effect of Siegesbeckiae Herba on 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 Siegesbeckiae Herba-induced relaxation, Siegesbeckiae Herba extract infused into contracted arterial strips induced by agonists after treatment of lanthanum chloride, indomethacin, atropine, $N\omega-nitro-{_L}-arginine$, cobalt chloride or methylene blue. The relaxation effect of Siegesbeckiae Herba was dependent on the presence of endothelium, showing that Siegesbeckiae Herba-induced relaxation was not observed in the strips without endothelium. The endothelium-dependent relaxation induced by Siegesbeckiae Herba was suppressed by the pretreatment of lanthanum chloride, $N\omega-nitro-{_L}-arginine$, cobalt chloride or methylene blue, but it was not observed in the strips pretreated with indomethacin or atropine. These results demonstrated that Siegesbeckiae Herba may inhibit agonist-induced contraction through an increase in the cyclic GMP by the production of nitric oxide in the vascular endothelial cells.

• Clinical and Experimental Pediatrics
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• 제52권3호
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• pp.385-388
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• 2009

8세 여아가 증상 발현 3일전부터 한약을 복용 후, 내원 20시간 전에 발생한 청색증과 호흡곤란을 주소로 응급실에 내원하였다. 내원 당시 메트헤모글로빈 수치가 23.7%로, 메트헤모글로빈혈증 진단 하에 methylene blue로 치료하였다. 한약 성분은 암모니아가 239.41 mg/L로 높게 측정되었다. 이에 한약 복용 후 발생한 메트헤모글로빈혈증 1예를 보고하고자 한다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2003년도 가을 학술논문집
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• pp.78-82
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• 2003

국내 원전에서 증기발생기 세정 후 발생되는 Fe-EDTA 함유 폐액 처리를 위한 초임계수 산화공정 (Supercritical Water Oxidation Process), 광촉매 산화 공정 (Photocatalyst Oxidation Process) 및 DBD 상온 플라즈마 공정 (Dielectric Barrier Discharge Atmospheric Pressure Plasma Process)이 평가되었다. 초임계수 산화 공정에 의해 99.98 %이상의 EDTA 전환율을 나타내어 EDTA 처리를 위한 효과적인 반응공정임을 확인하였으나 공정의 안정성, 부식 방지대책 등이 마련되어야 할 것으로 판단된다. 광촉매산화공정으로는 10 % 정도의 낮은 EDTA전환율을 보여 세정폐액 처리 공정으로는 부적합한 것으로 나타났다. DBD를 이용한 Methylene Blue 분해 결과 저 에너지 소비율로 높은 유기물 분해 효율을 얻을 수 있었으나 실 EDTA 공정에의 적용 및 공정 규모 확장 등에 대한 향후 연구 평가가 필요한 것으로 사료된다.

• 대한치과보철학회지
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• 제37권4호
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• pp.416-424
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• 1999

Simulation of naturally appearing enamel in fixed prosthodontics could be achieved with all ceramics. The purpose of this study was to investigate the stain resistance of 4 different all ceramics materials (In-ceram, IPS Empress, Celay, Vintage). Forty specimens were prepared using manifacture's instruction and the samples were divided into two groups. The specimens for one group were glazing and those for other group were ground to remove the glazing layer. All specimens were immersed in methylene-blue for 24hours. The color values for each specimen was measured with colorimeter (Mode Tc-6Fx, Tokyo Denshoku Co.) prior to and after immersion in methylene-blue. The following conclusions were drawn from this study. 1 The stain resistance of glazing ceramics was higher than that of unglazing ceramics. 2. The changes of ${\Delta}E^*$\;and\;L^*$ values were revealed in Vintage and unglazing Celay. 3. The changes of $a^*$ values were revealed in unglazing vintage, Celay, In-ceram. 4. The changes of $b^*$ value were revealed in Vintage, IPS Empress and unglazing Celay.

• 한국세라믹학회지
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• 제45권6호
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• pp.324-330
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• 2008

Activated carbon/$TiO_2$ (AC/$TiO_2$) composites modified with different concentrations of Fe were prepared. The $N_2$ adsorption data showed that the composites had decreased surface area compared with the pristine activated carbon. This indicated the blocking of the micropores on the surface of AC, which was further supported by observation via SEM. XRD results showed patterns for the composites and an anatase typed titanium dioxide structure with a small part of rutile in a higher Fe concentration (> 1.0 mol/L). EDX results showed the presence of C and, O, with Ti peaks on the composites of Fe-AC/$TiO_2$ with relatively lower Ti concentration, which may be due to the higher Fe concentration incorporated into the composites. Subsequently, the photocatalytic effects on methylene blue (MB) were investigated. The improved decomposition of MB showed the combined effects of adsorptions and photodegradation. Especially, the composites modified by Fe revealed enhanced photodegradation behaviors of MB.

• 한국세라믹학회지
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• 제45권11호
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• pp.651-657
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• 2008

In this study, CNT/$TiO_2$ composites were prepared using surface modified Multiwall carbon nanotube (MWCNT) and titanium n-butoxide (TNB) with benzene. The composites were characterized by nitrogen adsorption isotherms, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), FT-IR spectra, and UV-vis absorption spectroscopy. The UV radiation induced photoactivity of the CNT/$TiO_2$ composites was tested using a fixed concentration of methylene blue (MB, $C_{16}H_{18}N_3S{\cdot}Cl{\cdot}3H_2O$) in an aqueous solution. Finally, it can be considered that the MB removal effect of the CNT/$TiO_2$ composites is not only due to the adsorption effect of MWCNT and photocatalytic degradation of $TiO_2$, but also to electron transfer between MWCNT and $TiO_2$.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.243-247
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• 2012

Photocatalysis has been applied to decompose the waste and toxic materials produced in daily life and in the global environment. Pure $TiO_2$ (Zn-$TiO_2$-0) and Zn-doped $TiO_2$ (Zn-$TiO_2$-x, x = 3-10 mol %) samples were synthesized using a novel sol-gel and ammonia-evaporation method. The Zn-doped $TiO_2$ samples showed high photocatalytic activity for the degradation of methylene blue (MB). The physicochemical properties of the samples were investigated using XRD, SEM, ICP, DLS and BET methods. In addition, the most important measurement of photocatalytic ability was investigated by a UV-vis spectrophotometer. The effects of the mol % of zinc ion doping in $TiO_2$ on photocatalytic activity were studied. Among the mol % Zn ions investigated, the Zn-$TiO_2$-9 sample showed the highest photoreactivity. This sample removed 91.4% of the MB after 4 h, while the pure $TiO_2$ only removed 46.4% of the MB.

• Journal of Ginseng Research
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• 제16권3호
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• pp.175-182
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• 1992

Intravenous administration of saponin from the root of Panax ginseng (red ginseng) lowered the blood pressure in a dose-dependent manner (10~100 mg/kg B.W) in anesthetized rats. Therefore, experiments were designed to study whether this lowering of blood pressure is associated with the release of endothelium-derived relaxing factor. Rings of thoracic aorta with and without endothelium were suspended for the measurement of isometric tension in organ chamber. All experiments were performed in the presence of indomethacin (10-5 M). Ginseng saponin (10-5~3$\times$10-4 g/ml) relaxed contractions induced by phenylephrine (10-5 M) in the aorta with endothelium but not in that without endothelium. Treatment of aortic rings with NG_monomethyl-L-arginine (L-NMMA 10-4 M for 30 min), a competive inhibitor of nitric oxide synthase and methylene blue (M.B., 3$\times$10-7 M for 30 min), an inhibitor of soluble guanylate cyclase, diminished the relaxation induced by ginseng saponin. In thoracic aortic rings from rats treated with ginseng saponin for 2 weeks intraperitoneally, the relaxation to acetylcholine was increased compared with non-ginseng treated rings. These data suggest that red ginseng saponin evokes hypotension and that vascular relaxations induced by red ginseng saponin are inediatpd by release of endothelium-derived relaxing factor.

• 한국결정성장학회지
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• 제20권1호
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• pp.35-42
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• 2010

In this paper, three types of CNT/$TiO_2$ composite electrodes were prepared with different methods. The changes in XRD patterns showed that the Electrode A contained a mixed phase of anatase and rutile while the Electrode B and Electrode C contained a typical single and clear anatase crystal structure. From SEM micrographs, $TiO_2$ particles were adhered on the surface of the CNT network in the forms of small clusters. The results of chemical elemental analysis indicated that the main elements such as C, O and Ti were existed. The results demonstrated that the efficiency of photoelectrocatalytic (PEC) oxidation for methylene blue (MB) was higher than that of photocatalytic (PC) oxidation. There was a clear enhancement trend of the MB degradation using the prepared CNT/$TiO_2$ composite electrodes with an increase of applied potential. Finally, the prominent PEC activities of the CNT/$TiO_2$ composites could be attributed to combination effects of photo-degradation of $TiO_2$, electron assistant of CNT and function of applied potential.

• Bulletin of the Korean Chemical Society
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• 제30권8호
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• pp.1798-1804
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• 2009

In this study, we have studied on improved performance of carbon nanotubes/titanium (CNT/TiO2) structure electrode for methylene blue (MB). The composite electrodes consisting of CNTs and a titanium oxide matrix with phenol resin binder was fabricated with a mixture method. The chemical and morphological structure of CNT/Ti$O_2$ composites were characterized by means of BET surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-Vis absorption technique, Raman spectroscopy and energy dispersive X-ray (EDX). The electrode showed a remarkably enhanced performance for MB oxidation under UV illumination with or without electro-chemical reaction (ECR). Such a remarkably improved performance of the CNT/Ti$O_2$ structure electrode might be due to the enhanced MB oxidation by electro- and photo-generated electrons and holes in the CNTs and Ti$O_2$ under UV illumination with or without ECR.