• 대한화학회지
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• 제39권1호
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• pp.57-65
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• 1995

$1.0{\times}10^{-2}M\; KNO_3$ 수용액에서 methylene blue(MB)의 전기화학적 환원을 직류 및 펄스차이 폴라로그래피, 순환 전압-전류법, 조절 전위 전기량법으로 조사하였다. MB의 전극환원은 처음 가역파(-0.18 volts vs. Ag/AgCl)에서 2전자 이동의 CE 반응기구로 진행되었다. Methylene blue는 정지된 수은전극에 강하게 흡착되었으며, 조절 전위 전기분해로 환원된 생성물은 공기중에서 빠르게 자동산화되어 본래의 MB로 돌아왔다. pH 변화에 따른 순환 전압-전류 그림과 폴라로그램의 해석을 근거로 하여 CE 반응기구를 제시하였다.

• 대한화학회지
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• 제35권6호
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• pp.612-616
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• 1991

Sodium dodecyl sulfate(SDS), chondroitin sulfate 그리고 L-${\alpha}$-lecithin vesicle의 각각의 수용액에서 methylene blue (MB)의 metachromatic 성질을 $18^{\circ}$C에서 $52^{\circ}$C까지 흡수분광법으로 측정했다. MB는 지질이 고농도일 때 vesicle 매트릭스에 뭉치를 형성했다. MB의 metachromasy는 vesicle의 상전이 온도에 무관하게 나타났으며, 이것은 색소가 vesicle의 친수성 표면에서 회합함을 의미한다. Vesicle에서 MB의 metachromasy 현상은 hexadecyltrimethylammonium bromide(CTAB)를 첨가할 때보다 SDS를 첨가할 때 매우 약하게 관측되었다. 이것은 vesicle 표면에서 계면활성제들의 끼어드는 위치가 다른 것으로 보이며, CTAB가 SDS보다 색소뭉치 사이에 더욱 잘 끼어드는 것으로 사료된다.

• 한국응용과학기술학회지
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• 제14권2호
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• pp.103-114
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• 1997

Metachromatic properties of admixture of methylene blue(MB) and thionine in aqueous solution has been studied by fluorescence spectroscopy. In spite of nonfluorescence character has been MB itself, mixing MB to monomeric concentration of thionine, new coaggregation band has been formed in shorter wave length than fluorescence of thionine because of MB was redistributed to thionine aggregate. It suggested that coaggregate of MB and thionine were more tightly formed than the each dye aggregate.

• 대한화학회지
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• 제28권6호
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• pp.355-360
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• 1984

Methylene blue(MB$^+$)와 tetraphenylborate(TPB$^-$)이 공존하는 묽은 수용액에서 MB+만의 흡수스펙트럼보다는 장파장 쪽에서 스펙트럼의 변화를 관찰하고, 이를 나타내는 화학종에 관한 연구를 흡수분광법으로 수행하였다. 소수성이 큰 이들 두 이온의 물의 구조를 덜 깨뜨리려는 힘에 의하여 이온쌍으로 되고 더 나아가 전자밀도가 높은 TPB$^-$로 부터 전자가 옮겨진 전하이동 착물이 그것일수도 있다. 그러나 MB$^+$만의 최대 흡수 파수를 기준으로 1,000cm$^{-1}$ 만큼 높고 낮은 두 흡수띠를 보였으므로 중이온쌍, (MB-TPB)$_2$가 새로운 흡수를 보이는 주된 화학종으로 생각되었다.

• 한국환경과학회지
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• 제22권11호
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• pp.1433-1441
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• 2013

The adsorption ability of wood-based activated carbon to adsorb methylene blue (MB) and crystal violet (CV) from aqueous solution has been investigated. Adsorption studies were carried out on the batch experiment at different initial MB and CV concentrations (MB=150 mg/L~400 mg/L, CV=50 mg/L~350 mg/L), contact time, and temperature. The results showed that the MB and CV adsorption process followed the pseudo-second-order kinetic and intraparticle diffusion was the rate-limiting step. Adsorption equilibrium data of the adsorption process fitted very well to both Langmuir and Freundlich model. The maximum adsorption capacity ($q_m$) by Langmuir constant was 416.7 mg/g for MB and 462.4 mg/g for CV. The thermodynamic parameters such as ${\Delta}H^{\circ}$, ${\Delta}S^{\circ}$ and ${\Delta}G^{\circ}$ were evaluated. The MB and CV adsorption process was found to be endothermic for the two dyes.

• 한국응용과학기술학회지
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• 제13권3호
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• pp.43-49
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• 1996

Metachromatic properties of admixture of thionine and methylene blue(MB) in aqueous solution and phospholipid bilayer membrane have been studied by absorption spectroscopy. When thionine and MB were mixed, new coaggregate has been formed because of MB was redistributed to thionine aggregate. In phosphlipid bilayer membrane system, the highly concentrated thionine was easily formed the coaggregation with MB moiety independent of MB concentration, and absorption band of admixture were more transferred to short wavelength than aqueous system. In monomeric thionine concentration, the coaggregation band was observed at the middle wavelength between the site of monomeric thionine and the site of dimeric MB in the presence of lipid bilayer membrane.

• Environmental Engineering Research
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• 제24권1호
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• pp.99-106
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• 2019

Using the abandoned agricultural by-product corncobs, the most commonly used methylene blue (MB) dyestuffs were removed. This experiment is very meaningful because it is the recycling of resources and the use of environmentally friendly adsorbents. According to the Hauser ratio and porosity analysis, the corncob has a good flow ability of the adsorbent material and many pores, which is very advantageous for MB adsorption. As a result of the experiment, MB concentration of less than 0.005 g/L was very efficiently removed with 10 g/L of bioadsorbent corncob and the maximum adsorption capacity of corncob for MB dyes was obtained at 417.1 mg/g. In addition, adsorption process of MB onto corncob was a physical process according to adsorption energy analysis. Corncob can efficiently and environmentally remove MB in aqueous solution, and is very cost effective and can recycle the abandoned resources.

• 대한화학회지
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• 제36권4호
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• pp.504-510
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• 1992

L-${\alpha}$-lecithin vesicle, bacteriorhodopsin(BR) 그리고 인지질로 재구성된 BR vesicle(InBR vesicle)의 각각의 수용액에서 methylene blue(MB)의 흡수성질을 $20^{\circ}C$에서 $60^{\circ}C$까지 흡수분광법으로 측정하였다. 인지질 vesicle에서 묽은 농도의 MB는 단위체와 이합체 사이에 평형을 이루었고, 고농도의 MB는 oligomer를 형성하였다. 대부분의 경우에 지질(vesicle)의 농도가 매우 높아지면 점점 단위체로 재분배 되었다. 일정한 MB 농도에 BR를 첨가할 때 흡광도비(${\alpha}/{\beta}$)는 감소되며 oligomer가 형성되었다. MB는 InBR vesicle의 상전이 온도 부근에서 흡광도비(${\alpha}/{\beta}$)가 증가했으나 인지질 vesicle에서는 상전이에 무관했다. 이것은 InBR vesicle 표면 위에서 회합하는 MB 분자들은 지질의 상전이에 영향을 받아 단위체로 재분배되는 것으로 사료된다.

• Archives of Pharmacal Research
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• 제18권3호
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• pp.159-163
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• 1995

Previously, we have reported that methylene blue (MB) induces cytotoxicity in human brain tumor cells through the generation of free radicals. In this study the effect of deferoxamine (DFO), an iron chelator, on MB-induced cytotoxicity was investigated using SK-N-MC human neuroblastoma and U-373 MG human astrocytoma cells as model cellular systems. The cytotoxic effect of MB was potentiated by DFO. The potentiation effect of DFO was significantly blocked by either stoichiometric amounts of ferric ion, various antioxidants, hydroxyl radical scavengers or intracellular $Ca^{2+}$ release blockers. These results suggest that hydroxyl radical and intracellular $Ca^{2+}$ may act as important mediators of the enhanced cytotoxicity by MB and DFO. These results further suggest that the combined treatment with MB and DFO may be useful for the therapeutical applications of human brain tumors.

• Advances in environmental research
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• 제5권1호
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• pp.37-50
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• 2016

The main objective of this study is to evaluate adsorptive removal of Methylene Blue (MB) dye from aqueous solution using pumice powder. The effects of pH, adsorption time, agitation speed, adsorbent dose, and dye concentrations on dye adsorption were investigated. Process kinetics and isotherm model constants were determined accordingly. The results showed that adsorbent dose, dye concentration and agitation speed are the important parameters on dye adsorption and the removal of MB did not significantly change by varying pH. A total adsorption process time of 60 min was observed to be sufficient to effectively remove 50 mg/L MB concentration. The MB adsorption data obeyed both pseudo first order and second order kinetic models. Adsorption of MB by pumice fitted well both Langmiur and Freundlich isotherms ($R^2{\geq}0.9700$), except for 150 rpm agitation speed that system fitted only Langmiur isotherm. The results of this study emphasize that pumice powder can be used as a low cost and effective adsorbent for dye removal.