• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.278-282
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• 2018

The development of treatment technologies for recycling waste woods generated from tree pruning is required in Gangwon province forest. In this study, according to adsorption experiments using three types (Larix kaemoferi, Juniperus chinensis, Pinus densiflora) of waste woods, Juniperus chinensis as a biosorbent showing an excellent removal ability was selected for the removal of methylene blue in an aqueous phase. When 0.4 g/100 mL of Juniperus chinensis was used to improve the removal efficiency of methylene blue for 4 h, each 100, 200 and 300 mg/L of methylene blue dissolved in the aqueous phase were removed to 98, 93, and 81%, respectively. The adsorption equilibrium data obtained by changing adsorbent concentrations was found to be more consistent with the Langmuir than the Freundlich equation. In addition, based on dynamic experiments by changing the methylene blue concentration, the biosorption kinetics equation was more suitable for a pseudo-second order model. In order to enhance the removal capability of highly concentrated methylene blue, 300 and 400 mg/L of methylene blue were operated for 4 h under 210 rpm of agitation velocity and removal efficiencies were 92 and 76%, respectively. Consequently, these experimental results can be effectively utilized as a new biosorption technology for economically treating methylene blue dissolved in an aqueous phase.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.3
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• pp.356-364
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• 2020

An experimental study to investigate the effect of self-cleaning of mortar mixed with photocatalyst was performed out in this study. Test parameters included the photocatalyst content and surface roughness of the specimens. The experimental mortar specimens were manufactured by mixing a photocatalyst by cement weight of 2.5%, 5.0%, 7.5% and 10.0%. In addition, the surface roughness was categorized into three cases. They included flat surface condition, little surface roughness(medium roughness), and high surface roughness. After mortar specimens were cured for 28 days, they were illuminated by an ultraviolet lamp for 24 hours and immersed in a methylene blue conditioning solution for 12 hours. Thereafter, an ultraviolet(UV) lamp was illuminated on the specimens for 48 hours in an experimental chamber and then the color change of methylene blue solution was measured by using a spectrophotometer over illuminating time of UV lamp. The color change of methylene blue tended to increase as photocatalyst contents increased. Test results meant that photocatalyst was effective for self-cleaning in mortar. However, the color change of the methylene blue solution did not show a noticeable tendency at different surface roughness conditions. It might be due to the uneven photocatalyst distribution on the surface of mortar specimens.

• Korean Journal of Food Science and Technology
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• v.42 no.3
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• pp.277-280
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• 2010

Bisphenol A (BPA) is an endocrine disruptor frequently used in food containers, including epoxy resin and polycarbonates. BPA concentrations were monitored by high performance liquid chromatography (HPLC) under photosensitization of riboflavin (RF), methylene blue (MB), rose bengal (RB), or titanium dioxide ($TiO_2$) and the involvement of singlet oxygen was determined using sodium azide ($NaN_3$). The stability of BPA decreased significantly in the order of RF, RB, and MB photosensitization (p<0.05), while the concentration of BPA in samples with $TiO_2$ was not significantly different from that of control samples without photosensitizers under light (p>0.05). The stability of BPA decreased in an MB concentration-dependent manner and increased as the concentration of added $NaN_3$ increased, implying that singlet oxygen was involved in the photodegradation of BPA during MB photosensitization. The results of this study may help control the BPA content in foods or the environments using photosensitized oxidation and visible light irradiation.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2348-2353
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• 2007

In this work, combustion-synthesized $TiO_2$ nanoparticles were used for the photocatalytic degradation of methylene blue with UV light irradiation. Also the results were compared with those of commercial $TiO_2$ nanoparticles (Degussa, P-25). Particle characteristics of the two were analyzed thru the SEM, TEM, and XRD. In spite of the lower specific surface area than that of P-25, the $TiO_2$ nanoparticles formed in this study showed the relatively good ability to degrade the concentration of the organics.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.5-12
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• 2017

Effects of operating parameters such as activated carbon dose, gaseous $O_3$ concentration and pH on the properties of methylene blue(MB) degradation in a catalytic ozonation were investigated through a series of batch experiments. Activated carbon catalyzed the self-decomposition of ozone, generating $OH{\cdot}$, thus promoting MB degradation. Thus the increase of activated carbon dose enhanced the MB and TOC removal. The higher gaseous ozone concentration injected, the promoted MB and TOC removal obtained through the enhanced mass transfer. The MB removal was not significantly affected by the variation of aqueous pH. Catalytic ozonation can be considered as an efficient alternative in treating refractory pollutants in textile wastewater with faster and higher dye and TOC removal compared with ozonation and adsorption.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.3
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• pp.393-399
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• 2018

The aim of this review is to introduce about the issue of benzocaine and methemoglobinemia. Through blocking the pain during dental treatment, fear and anxiety of patients will be reduced. Thus, anesthetic agent containing benzocaine is commonly used while controlling the pain of patients during treatment. However, on May 28, 2018, the Ministry of Food and Drug Safety reported a medication safety report about restricting the use of benzocaine-containing agents in infants under 24 months and children. Also, they recommended a cautious use to adolescents and adults to prevent methemoglobinemia (MHb). This report was published due to an advice from Food and Drug Administration (FDA) on May 23, 2018. When using agents containing benzocaine, dentists must consider the probability of MHb and prepare for early diagnosis and appropriate action. Since 1930s, methylene blue is known to cure MHb patients. Therefore, the proper use of methylene blue for emergencies and diagnosis methods for early diagnosis of MHb should be familiar to dentists planning for the use of topical anesthetic agents. Dentists should be trained for emergency situation of MHb caused by the use of benzocaine.

• Journal of Chest Surgery
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• v.40 no.4 s.273
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• pp.305-308
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• 2007

Vasoplegic syndrome occurs in $8{\sim}10%$ of patients following cardiac surgery, and this happens in part because of inducing the inflammatory response. Nitric oxide and guanylate cyclase play an important role in this response, and this is associated with increased morbidity and mortality. For our case, we administered methylene blue (MB), an inhibitor of guanylate cyclase, early after performing cardiopulmonary bypass in a patient with vasoplegic syndrome. The patient recovered immediately after MB administration and maintained an optimal blood pressure without the aid help of any vasopressors.

• Applied Chemistry for Engineering
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• v.21 no.3
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• pp.323-327
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• 2010

Ti-SBA-15 catalysts doped with lanthanide ion were synthesized using conventional hydrothermal method and they were characterized by XRD, FT-IR, DRS, $NH_3$-TPD and PL. We also examined the activity of these materials on the photocatalytic decomposition of methylene blue. La/Ti-SBA-15 samples with varying lanthanide ions doping maintained the mesoporous structure and the catalysts calcined at $500^{\circ}C$ for 6 h showed the highest crystallinity. With increasing the doping amount of lanthanide ion, the pore size and pore volume of La/Ti-SBA-15 materials decreased but the surface area increased. 1% La/Ti-SBA-15 catalysts showed the highest photocatalytic activity on the decomposition of methylene blue but the catalysts doped with more than 5% lanthanide ions showed lower activity compared to pure Ti-SBA-15 catalyst.

• Resources Recycling
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• v.14 no.1
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• pp.47-54
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• 2005

Korean grape-seed that is one of the agricultural waste was used as a raw material to prepare activated carbon through roasting, carbonization and chemical activation processes. NaOH, KOH, ZnCl$^2$ were also used as activation reagents. The mixing of the ratios of the grape-seed and each activation reagent were varied to 100-300 weight percent. The surface areas of the activated carbon manufacture from the grape-seed were 44.09~121.33 m$^2$/g. The adsorbate transmittance of methylene blue was determined UV absorption at 660 nm as maximum adsorption wavelength using by UV spectrophotometer. As a result, adsorption of methylene blue on the activated carbon prepared with NaOH activation was more successful than others. Equilibrium absorption time was approximately 60 min.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.61-66
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• 2011

In this study, we prepared $TiO_2$ with the sol-gel method and controlled physico-chemical properties by a simple heat treatment. All materials were applied to photocatalytic decomposition of methylene blue and the material treated at 473 K showed the highest photocatalytic efficiency. The high performance resulted from a high adsorption amount of methylene blue due to a high surface area of $229.8m^2/g$. However, the material treated at 873 K, despite of a low surface area of $23.8m^2/g$ and a large particle size of 28.38 nm, exhibits a good photocatalytic performance due to the effect of mixed cyrstalline rutile and anatase phases formed by the high heat treatment temperature.