• Journal of Korean Society of Environmental Engineers
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• v.35 no.9
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• pp.636-642
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• 2013

In order to overcome drawbacks (i.e., filtration and recovery) of conventional powder type photocatalysts, nano-ZnO/Laponite/PVA (ZLP) photocatalyzed adsorption balls were developed by using in situ mixing of nanoscale ZnO as a photocatalyst, and Laponite as both adsorbent and supporting media in deionized water, followed by the poly vinyl alcohol polymerization with boric acid. The optimum mixing ratio of nano-ZnO:Laponite:PVA:deionized water was found to be 3:1:1:16 (by weight), and the mesh and film produced by PVA polymerization with boric acid might inhibit both swelling of Laponite and detachment of nanoscale ZnO from ZLP balls. Drying ZLP balls with microwave (600 watt) was found to produce ZLP balls with stable structure in water, and various sizes (55~500 ${\mu}m$) of pore were found to be distributed based on SEM and TEM results. In the initial period of reaction (i. e., 40 min), adsorption through ionic interaction between methylene blue and Laponite was the main removal mechanism. After the saturation of methylene blue to available adsorption sites for Laponite, the photocatalytic degradation of methylene blue occurred. The effective removal of methylene blue was attributed to adsorption and photocatalytic degradation. Based on the results from this study, synthesized ZLP photocatalyzed adsorption balls were expected to remove recalcitrant organic compounds effectively through both adsorption and photocatalytic degradation, and the risks of environmental receptors caused by detachment of nanoscale photocatalysts can be reduced.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.21-25
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• 2011

In this study, anatase/brookite hybrid $TiO_2$ was prepared using different acid catalysts and microwave to improve photodegradation of organic pollutants. The methylene blue photodegradation properties of the prepared photocatalysts with different particle/crystal size and brookite fractions were investigated. Surface characteristics and particle sizes of anatase/brookite hybrid $TiO_2$ were evaluated using scanning electron microscopy (SEM) and laser diffraction particle size analyzer, respectively and crystal structures were investigated with X-ray diffraction (XRD). Methylene blue photodegradation properties were evaluated with UV-vis spectrophotometer. Anatase and anatase/brookite hybrid $TiO_2$ had less than 500 nm size of clusters and the average particle size of $6.66{\sim}6.85{\mu}m$, suggesting that types of acid catalysts did not affect the size. XRD of the prepared $TiO_2$ showed that the photocatalysts had anatase/brookite hybrid crystal structure and applying microwave did not change their crystal structure. Photodegradation of methylene blue with the prepared photocatalyst did not increased proportionally to the fraction of brookite and the crystal size and decreased when brookite fraction and the crystal size increased further. Anatase/brookite hybrid $TiO_2$ with brookite fraction of 9.4% and crystal size of 4.53 nm shows the best photodegradation activity of methylene blue.

• Journal of Acupuncture Research
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• v.29 no.2
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• pp.73-88
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• 2012

Objectives : The purpose of this study is to research the effects of acupuncturing $BL_{67}$ and $LI_1$ and determine the mechanism of action of acupuncturing $BL_{67}$ and $LI_1$ by measuring the changes of regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP) in normal rats and ischemic rats. Method : This study researched the effects of acupuncturing $BL_{67}$ and $LI_1$ on the change of rCBF and MABP. To determine the mechanism of action of acupuncturing $BL_{67}$ and $LI_1$, pretreatment with indomethacine and methylene blue was done. Result : 1. Acupuncturing $BL_{67}$ and $LI_1$ significantly increased rCBF and acupuncturing $BL_{67}$ and $LI_1$ induced increase of rCBF was significantly inhibited by pretreatment with indomethacin(1 mg/kg, i.p.), an inhibitor of cyclooxygenase, and methylene blue(10 ${\mu}g$/kg, i.p.), an inhibitor of guanylate cyclase. 2. Acupuncturing $BL_{67}$ and $LI_1$ decreased MABP and there was no significantly change of decrease of MABP on acupuncturing $BL_{67}$ and $LI_1$ by pretreatment with indomethacin and methylene blue. 3. These result suggested that acupuncturing $BL_{67}$ and $LI_1$ might significantly increase rCBF by dilating arterial diameter and mechanism of acupuncturing $BL_{67}$ and $LI_1$ might be mediated by cyclooxygenase and guanylate cyclase. 4. The rCBF was significantly and stably increased by acupuncturing $BL_{67}$ and $LI_1$ during the period of cerebral reperfusion in cerebral ischemic rats, which contrasted with the rapid and marked increase in the control group. Pretreatment with methylene blue significantly decreased rCBF by acupuncturing $BL_{67}$ and $LI_1$ during the period of ischemic state, increased rCBF during the period of cerebral reperfusion. These results suggested that the mechanism of acupuncturing $BL_{67}$ and $LI_1$ might be mediated by guanylate cyclase. Conclusion : Acupuncturing $BL_{67}$ and $LI_1$ can increase rCBF in normal state, and improve stability of rCBF in ischemic state. In addition, we suggested that mechanisms related with acupuncturing $BL_{67}$ and $LI_1$ was more involved in the guanylate cyclase pathway.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.817-822
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• 2008

In this study, the photocatalytic degradation of methylene blue in TiO$_2$ particles-dispersed water solution was carried out by irradiating microwave and UV light simultaneously. A microwave-discharged electrodeless UV lamp was developed to use microwave and UV simultaneously for photocatalytic reactions. The results of photocatalytic degradation of methylene blue showed that the decomposition rate increased with the microwave intensity, the circulating fluid velocity, and the amount of TiO$_2$ particles and auxiliary oxidizing agents added. Especially, the rate constant of H$_2$O$_2$-added photocatalytic reaction increased about three times from 0.0075 min$^{-1}$ to 0.0250 min$^{-1}$ when microwave was additionally irradiated. This study demonstrates that the microwave irradiation can play a very important role in photocatalytic degradation using peroxides although it is not easy to quantitatively assess the effect of microwave on photocatalytic reactions from the experimental data of this study.

• The Korean Journal of Pharmacology
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• v.27 no.2
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• pp.125-133
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• 1991

In the isolated rabbit mesenteric artery denuded of endothelium, we characterized the identity of the A23187-induced endothelium-dependent relaxing factor (EDRF) released from the endothelium of rabbit aorta, which is distinct from that of acetylcholine-induced relaxing factor. In the normal physiological salt solution (PSS), the dose-response curves to A23187 and acetylcholine were overlapped together. Their effects were also inhibited by methylene blue. Upon application of hypoxanthine and xanthine oxidase into the bath, the phenylephrine-induced precontraction was transiently increased followed by the sustained relaxation. During the burst of hypoxanthine-xanthine oxidase reaction, the $Ca^{++}$ ionophore, A23187 but not acetylcholine was able to cause an immediate relaxation. However, A23187-induced relaxation was not manifested when precontracted by 50 mM $K^+-PSS$. Nevertheless, in the presence of superoxide dismutase, A23187 could produce an immediate relaxation without accompanying the transient contraction as acetylcholine did during the hypoxanthine-xanthine oxidase reaction. On the other hand, acetylcholine-induced relaxation was more sensitively inhibited by phorbol 12-myristate 13-acetate (PMA) than A23187-induced relaxation. Endothelium-independent relaxation to sodium nitroprusside was not affected by PMA. Based on these results it is suggested that both A23187 and acetylcholine cause the methylene blue-inhibitable endothelium-dependent relaxation, and in addition, A23187 may release a stable EDRF which is resistant to superoxide anion and PMA.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.420-424
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• 2016

In this study, we developed photocatalytic technology to address the emerging serious problem of air pollution through indoor air cleaning. A single layer of $WO_3$ was prepared by using the dry process of general RF magnetron sputtering. At a base vacuum of $1.8{\times}10^{-6}$[Torr], the optical and electrical properties of the resulting thin films were examined for use as a transparent electrode as well as a photocatalyst. The single layer of $WO_3$ prepared at an RF power of 100 [W], a pressure of 7 [mTorr] and Ar and $O_2$ gas flow rates of 70 and 2 sccm, respectively, showed uniform and good optical transmittance of over 80% in the visible wavelength range from 380 [nm] to 780 [nm]. The optical catalyst characteristics of the $WO_3$ thin film were examined by investigating the optical absorbance and concentration variance in methylene blue, where the $WO_3$ thin film was immersed in the methylene blue. The catalytic characteristics improved with time. The concentration of methylene blue decreased to 80% after 5 hours, which confirms that the $WO_3$ thin film shows the characteristics of an optical catalyst. Using the reflector of a CCFL (cold cathode fluorescent lamp) and the lens of an LED (lighting emitting diode), it is possible to enhance the air cleaning effect of next-generation light sources.

• Clean Technology
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• v.26 no.1
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• pp.7-12
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• 2020

Ti-SBA-15 catalysts doped with lanthanide ions (Ln/Ti-SBA-15) were successfully synthesized using conventional hydrothermal method. In addition, they were characterized by XRD, FT-IR, DRS, BET, and PL. The activity of these materials on the photocatalytic decomposition of methylene blue under ultraviolet light irradiation was also examined. Ti-SBA-15 catalysts doped with various lanthanide ions maintained their mesoporous structure. The pore size and pore volume of Ln/Ti-SBA-15 materials decreased but their surface area increased upon the doping of lanthanide ion. Ln/Ti-SBA-15 materials exhibited the type IV nitrogen isotherm with desorption hysteresis loop type H2, which was characteristic of mesoporous materials. The size of hysteresis increased in the doping of lanthanide ions on Ti-SBA-15 material. There was no absorption in the visible region (> 400 nm) regardless of the doping of lanthanide ions to TiO₂ particles, while the broad bands at 220 nm appeared at the Ln/Ti-SBA-15 samples, indicating the framework incorporation of titanium into SBA-15. 1 mol% Pr/ Ti-SBA-15 catalysts showed the highest photocatalytic activity on the decomposition of methylene blue but the Ti-SBA-15 catalysts doped with Eu, Er, and Nd ions showed lower activity compared to pure Ti-SBA-15 catalyst. The PL peaks appeared at about 410 nm at all catalysts while the excitonic PL signal was proportional to the photocatalytic activity for the decomposition of methylene blue.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.34-40
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• 2004

The purpose of this study was to measure the changes of regional cerebral blood flow (rCBF) and blood pressure (BP) in rats, following the intravenous injection of Schizandrae fructus water extract. The measurement was continually monitored by laser-doppler flowmeter and pressure tranducer in anesthetized adult Sprague-Dawley rats for 2 hours to 2 hours and a half through the data acquisition system composed of MacLab and Macintosh computer. The result of this experiment was as followed. Schizandrae fructus increased the changes of rCBF in rats significantly. The rCBF of Schizandrae fructus did not change by pretreated propranolol, atropine, L-NNA and indomethacin. But the rCBF of Schizandrae fructus was increased by pretreated methylene blue. Schizandrae fructus decreased the changes of BP, significantly. The BP of Schizandrae fructus did not change by pretreated propranolol, atropine, L-NNA and indomethacin. But the BP of Schizandrae fructus was decreased by pretreated methylene blue. There results indicated that Schizandrae fructus can increase the rCBF and decrease the BP, that is related to guanylyl cyclase activity.

• The Korean Journal of Mycology
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• v.40 no.2
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• pp.98-103
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• 2012

This study has been conducted to screen the decolorization of 4 aromatic synthetic dyes and production of ligninolytic enzymes by 4 white rot fungi such as Bjerkanderia adusta, Cerrena unicolor, Pleurotus pulmonarius and Abortiporus biennis. It was found that B. adusta, C. unicolor, and P. pulmonarius have the ability to efficiently decolorize congo red and moderately decolorized amaranth and orange G in solid and liquid culture media. However, the decolorization rate of 4 synthetic dyes by A. biennis was relatively low. The decolorization of congo red, amaranth, orange G were related to the growth rate of the fungal mycelia in the solid medium. But, the all fungi tested did not efficiently decolorize methylene blue in the liquid culture media. To investigate the production of ligninolytic enzymes in media containing aromatic compounds, fungi were cultured in 1% naphthalene supplemented potato dextrose broth medium. All fungi tested had the capability to produce laccase, lignin peroxidase and manganese peroxidase, and B. adusta was the best ligninolytic enzymes producing white rot fungus among other fungi tested.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.4
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• pp.423-430
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• 2019

In this study, the flexural strength, absorption rate, methylene blue photo catalyst decomposition performance and anti-fouling performance were evaluated according to the photo catalyst mixing rate and block surface wash status by applying photo catalyst to the surface layer of concrete sidewalk block. The results showed that the flexural strength of the block that mixed photo catalyst only in the surface layer of the concrete block was 5.32MPa of the general block (SNW) of 5% photo catalyst, compared to 5.46MPa of the non-mixed concrete block of the reference concrete block. Surface washing block (SW) 5.26MPa, 10% photo catalyst general block (SNW) 5.26MPa, and 5.15MPa surface washing block (SW). It has been shown that the presence of surface washing and the mixing rate of photo catalyst in the concrete block have no effect on the flexural strength. Moreover, the photoreaction performance of concrete sidewalk blocks showed that the methylene blue removal rate of specimens with 5% TiO₂ was 34.2%, the methylene blue removal rate of specimens with 10% TiO₂ was 37.1%, and the removal rate of the methylene blue of specimens with 5% TiO₂ was about 37.9% and 10% mixed specimens with TiO₂ was about 37.6%.