• 제목/요약/키워드: methylene-blue

검색결과 886건 처리시간 0.027초

Preparation of Different Fe Containing TiO2 Photocatalysts and Comparison of Their Photocatalytic Activity

  • Meng, Ze-Da;Zhang, Kan;Oh, Won-Chun
    • 한국재료학회지
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    • 제20권4호
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    • pp.228-234
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    • 2010
  • In this paper, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composite photocatalysts were prepared with titanium (IV) n-butoxide (TNB) by a sol-gel method. $TiO_2$, Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ were characterized by scanning electron microscopy (SEM), Transmission electron microscope (TEM), specific surface area (BET), X-ray diffraction analysis (XRD) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activities were evaluated by the photocatalytic oxidation of methylene blue (MB) solution. XRD patterns of the composites showed that the photocatalyst composite contained a typical single and clear anatase phase. The surface properties shown by SEM presented a characterization of the texture on Fe-fullerene/$TiO_2$ composites and showed a homogenous composition in the particles for the titanium sources used. The EDX spectra for the elemental identification showed the presence of O, C and Ti elements. Moreover, peaks of the Fe element were observed in the Fe-$TiO_2$ and Fe-fullerene/$TiO_2$ composites. The degradation of MB solution by UV-light irradiation in the presence of photocatalyst compounds was investigated in complete darkness. The degradation of MB concentration in aqueous solution occurred via three kinds of physical phenomena: quantum efficiency of the fullerene; organo-metallic reaction of the Fe compound; and decomposition of $TiO_2$. The degradation rate of the methylene blue solution increased when using Fe-fullerene/$TiO_2$ compounds.

붕소 착물 음이온의 이온쌍 추출 (제1보) (Ion-Pair Extraction of Boron Complex Anions (I). Methylene Blue-Tetrafluoroborate Complex)

  • 장호겸;김강진;김시중
    • 대한화학회지
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    • 제26권5호
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    • pp.326-332
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    • 1982
  • 플루오르화수소산 존재하에서 methylene blue의 양이온과 $BF_4^-$, 음이온이 이루는 착물을 1,2-dichloroethane과 nitrobenzene으로 용매추출하여 분광광도법으로 분석하였다. 적외선과 가시선 스펙트럼을 조사하여 이 착물은 1:1 조성비를 가지는 ion-pair로 존재하는 것으로 보이며 1,2-dichlorethane 중에서는 해리하지 않는 것을 알아냈다. 1,2-Dichlorethane에 대해서는 HF의 농도가 1.43${\times}10^{-2}$~ 2.86${\times}10^{-1}$M 범위에서 추출상수가 25$^{\circ}$C에서 1.1${\times}10^4M{-1}$로 일정한 값을 나타내었으며 nitrobenzene에 대하여는 대체로 10배 가량 큰 값을 가지지만 HF농도가 증가함에 약간씩 증가하였다.

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수열합성법에 의한 과산화티탄 수용액으로부터 이산화티탄의 합성 및 메틸렌블루의 광분해반응 (Synthesis of Titanium Dioxides from Peroxotitanate Solution Using Hydrothermal Method and Their Photocatalytic Decomposition of Methylene Blue)

  • 정원영;이승호;김대성;이근대;박성수;홍성수
    • Korean Chemical Engineering Research
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    • 제48권4호
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    • pp.417-422
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    • 2010
  • 서로 다른 관능기를 가진 카르복시산 화합물을 첨가제로 하여 과산화티탄 수용액으로부터 수열합성법으로 나노 크기의 이산화티탄을 제조하였다. 제조된 나노 크기의 이산화티탄의 물리적 성질을 조사하였으며, 이들을 사용하여 메틸렌블루의 광분해 반응에서의 활성을 조사하였다. 첨가된 카르복시산 화합물에 관계없이 아나타제형 나노 크기의 이산화티탄이 합성되었으며, 소성온도가 $700^{\circ}C$ 이상에서는 아나타제 결정구조가 루틸 결정구조로 변환되기 시작하였다. 광촉매 반응의 활성은 카르복시산의 탄소수가 커질수록 증가하였으며, 숙신산을 첨가제로 한 경우와 $500^{\circ}C$에서 소성시킨 경우에 가장 높은 활성을 보여주었다.

일체형 산화철 촉매를 전극으로 하는 전기펜톤산화법 (An Electro-Fenton System Using Magnetite Coated One-body Catalyst as an Electrode)

  • 최윤정;주재백;김상훈
    • 공업화학
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    • 제29권1호
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    • pp.117-121
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    • 2018
  • 하폐수 고도산화처리(AOP, advanced oxidation process) 중 하나인 펜톤산화법과 전기화학적 방법을 결합한 전기펜톤산화법의 cathode에 stainless steel mesh (SUS mesh)를 적용하였다. 난분해성 물질인 염료 methylene blue (MB) 용액에 대해서, SUS mesh의 표면 처리 및 산화철 코팅 여부에 따라 전기펜톤산화 처리의 효율이 어떻게 달라지는지를 비교, 분석하였다. MB분해 반응의 효율 비교를 통해 mesh 표면에 코팅된 산화철의 양이 많을수록 전극의 촉매 특성이 높아짐을 확인하였고, 이는 전극표면에서 in situ로 발생하는 과산화수소의 발생량이 높아지는 것과 연관이 있었다. 전류-전위 순환법(CV)을 통해 개발된 전극의 전기화학적 특성을 평가해 본 결과, mesh 표면에 코팅된 산화철의 양이 많을수록 전기화학적 산화-환원 특성 또한 개선되었고, 이것이 우수한 전기펜톤산화 전극으로서의 성능과 밀접한 관계가 있음을 확인하였다.

폐혈성 감염성 심내막염으로 개심술 후 발생한 Vasoplegic Syndrome에서 메틸렌 블루의 투여 후 혈압회복 - 1예 보고 - (Restoration of Blood Pressure after Administering Methylene Blue for Vasoplegic Syndrome, which Developed after Open Heart Surgery for Septic Infective Endocarditis -A case report -)

  • 이삭;배미경;이기종;윤영남;송석원;김도균
    • Journal of Chest Surgery
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    • 제40권4호
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    • pp.305-308
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    • 2007
  • Vasoplegic syndrome은 심장 수술 후 $8{\sim}10%$의 빈도로 발생하고, nitric oxide와 guanylate cyclase가 중요 역할을 하는 염증반응에 유도함에 기인하며, 높은 사망률과 유병률을 나타낸다. 본 증례에서는 수술 전 패혈증이 있던 환자에서 심폐순환 후 vasoplegenic syndrome이 발생하였다. Gguanylate cyclase 억제제인 메틸렌 블루(MB)를 투여하여 환자는 즉시 호전을 보였으며 어떠한 혈압수축제의 도움 없이도 적절한 혈압을 유지할 수 있었기에 보고한다.

개질 영가철을 이용한 산성 및 염기성 염료의 탈색 특성 (Decolorization Characteristics of Acid and Basic Dyes Using Modified Zero-valent Iron)

  • 최정학;김영훈
    • 한국환경과학회지
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    • 제25권12호
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    • pp.1717-1726
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    • 2016
  • In this study, the reductive decolorization of three acid and basic dyes using modified zero-valent iron (i.e., acid-washed iron (Aw/Fe) and palladium coated iron (Pd/Fe)) at various pH conditions (pH 3~5) was experimentally investigated and the decolorization characteristics were evaluated by analyzing the absorbance spectra and reaction kinetics. In the case of acid dyes such as methyl orange and eriochrome black T, color removal efficiencies increased as initial pH of the dye solution decreased. However, the color removal of methylene blue, a basic dye, was not affected much by the initial pH and more than 70% of color was removed within 10 min. During the decolorization reaction, the absorbance of methyl orange (${\lambda}_{max}=464nm$) and eriochrome black T (${\lambda}_{max}=528nm$) decreased in the visible range but increased in the UV range. The absorbance of methylene blue (${\lambda}_{max}=664nm$) also decreased gradually in the visible range. Pseudo-zero order, pseudo-first order, and pseudo-second order kinetic models were used to analyze the reaction kinetics. The pseudo-second order kinetic model was found to be the best with good correlation. The decolorization reaction rate constants ($k_2$) of methylene blue were relatively higher than those of methyl orange and eriochrome black T. The reaction rate constants of methyl orange and eriochrome black T increased with a decrease in the initial pH.

Mechanisms Underlying Relaxations Caused by Angiotensin II and Its Analogs in Isolated Rabbit Mesenteric Artery

  • Hong, Ki-Whan;Park, Ji-Young;Kim, Chi-Dae;Lee, Won-Suk;Rhim, Byung-Yong;Yoo, Sung-Eun
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권4호
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    • pp.393-402
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    • 1997
  • In the present study, we characterized the angiotensin II (AII)-induced relaxations in the phenylephrine-precontracted rabbit mesenteric arteries with endothelium. 1) AII-induced relaxation was consistently observed in the rabbit mesenteric arteries with and without endothelium, but not in the aortic segment with endothelium. 2) AII-induced endothelium-dependent relaxation was markedly inhibited by $N^w-nitro-L-arginine$ (L-NNA, $100\;{\mu}M$), methylene blue ($10\;{\mu}M$) and LY83583 ($10\;{\mu}M$), respectively. 3) Inhibition of cyclooxygenase with indomethacin ($10\;{\mu}M$) strongly decreased the vasorelaxant response to AII irrespective of the presence of endothelium. 4) 7-Ethoxyresorufin ($1\;{\mu}M$) and clotrimazole ($1\;{\mu}M$), inhibitors of cytochrome P-450-dependent arachidonic acid metabolism, greatly attenuated the vasodilator response to AII. 5) Carbacyclin, arachidonic acid and prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$) caused concentration-dependent relaxations in the mesenteric artery with endothelium, which were inhibited by L-NNA and methylene blue. 6) AII and $PGF_{2{\alpha}}$ significantly stimulated cyclic GMP formation in the mesenteric arteries with endothelium, which was inhibited by L-NNA and methylene blue, respectively. 7) AII enhanced synthesis of $PGF_{2{\alpha}}$ and 6-keto $PGF_{1{\alpha}}$ from the arterial segments with endothelium, which was inhibitable by indomethacin, but not by L-NNA. In conclusion, the vasorelaxant responses to AII of the rabbit mesenteric artery with endothelium are subserved by arachidonic acid and its metabolites produced via activation of cyclooxygenase and cytochrome P-450 enzyme as well as by nitric oxide.

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자음건비탕이 국소뇌혈류량, 평균혈압, 심근수축력에 미치는 작용기전 (Mechanism of Jaeumgenby-tang on the Regional Cerebral Blood Flow, Mean Arterial Blood Pressure and Cardiac Muscle Contractile Force in Rats)

  • 정현우;김희성;양기호
    • 동의생리병리학회지
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    • 제16권3호
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    • pp.507-513
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    • 2002
  • Jaeumgenby-tang(JGT) have been used in oriental medicine for many centries as a a therapeutic agent of vertigo caused by deficiency of qi and blood. The effects of JGT on the regional cerebral blood flow(rCBF), mean arterial blood pressure(MABP) and cardiac muscle contractile force(CMF) is not known. The purpose of this Study was to investigate effects of JGT on the rCBF, MABP, CMF and mechanism of JGT induced changed rCBF, MABP, CMF. The changes of rCBF, MABP and CMF were determinated by Laser-Doppler Flowmetry(LDF). The results were as follows; JGT extract was increased rCBF, MABP and CMF in a dose-dependent, specially JGT extract was significantly increased rCBF and MABP. Pretreatment with propranolol was significantly inhibited JGT induced increase of rCBF but pretreatment with indomethacin and methylene blue were accelerated JGT induced increase of rCBF. Pretreatment with propranolol and indomethacin were inhibited JGT induced increase of MABP, but pretreatment with methylene blue was accelerated JGT induced increase of MABP. Pretreatment with propranolol was significantly inhibited JGT induced increase of CMF but pretreatment with indomethacin and methylene blue were accelerated JGT induced increase of CMF. This results suggest that JGT increased rCBF by increasing MABP and CMF and the action of JGT is mediated by adrenergic β-receptor.

Iontophoresis Enhances Transdermal Delivery of Methylene Blue in Rat Skin (I): The Effect of Current Application Duration

  • Lee, Jae-Hyoung;Choi, Eun-Young
    • The Journal of Korean Physical Therapy
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    • 제23권6호
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    • pp.77-84
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    • 2011
  • Purpose: The objectives of this study were to determine the enhancing effect of iontophoresis method as it transdermally deliver methylene blue (MB) using visual examination, in terms of penetration depth and tissue distribution in the skin, and to determine the effect of application duration on the efficacy of iontophoresis. Methods: Twenty-four male Sprague-Dawley rats were randomly divided into 5-, 10-, 20-, and 40-minute groups. These rats were exposed to either topical or anodic iontophoresis of 1% MB using a direct current of $0.5mA/cm^2$ for 5, 10, 20, and 40 minutes. Using cryosections of rat tissues, the penetration depth of MB was measured using light microscopy. Results: Significant differences in the penetration depth (F=54.20, p<0.001) were detected among the four groups. Post hoc comparisons of the penetration depth of MB data pooled across groups showed no significant difference between all topical application groups and 5-minute iontophoresis group, but did reveal a significant difference in the penetration depth between all topical application groups and 5-minute iontophoresis group versus 10-minute group, between the 10-minute and 20-minute group, and between the 20-minute and 40-minute iontophoresis group (p<0.05). Conclusion: The results demonstrate that iontophoresis enhances transdermal delivery of MB across stratum corneum of skin barrier by visual examination. Furthermore, the penetration depth of iontophoretic transdermal delivery of MB was dependent on the application duration. The duration of iontophoresis is one of the important factor in the efficacy of iontophoresis application.

위중(委中)과 족삼리(足三里)의 자침이 뇌혈류 역학에 미치는 영향 (Effects of Acupuncture at the Wijung(BL40) and Chok-Samni(ST 36) on the Cerebral Blood Flow and Blood Pressure)

  • 정현우;김진우;한양신;;최찬헌
    • 동의생리병리학회지
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    • 제28권6호
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    • pp.601-606
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    • 2014
  • The purpose of this study is to research the effects of acupuncturing BL40 and ST36 and to determine the mechanism of action of acupuncturing BL40 and ST36 by measuring the changes of regional cerebral blood flow (rCBF) and mean arterial blood pressure (MABP) in normal rats. To determine the mechanism of action of acupuncturing BL40 and ST36, pretreatment with indomethacine and methylene blue was performed. Acupuncturing BL40 and ST36 significantly increased rCBF, and the increased rCBF by acupuncturing BL40 and ST36 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. Acupuncturing BL40 and ST36 decreased MABP, and decreased MABP by acupuncturing BL40 and ST36 was not changed by pretreatment with indomethacin and methylene blue. This result suggested that acupuncturing BL40 and ST36 might significantly increase rCBF by dilating arterial diameter and mechanism of acupuncturing BL40 and ST36 might be mediated by cyclooxygenase and guanylate cyclase.