• 제목/요약/키워드: Oxidation efficiency

검색결과 952건 처리시간 0.033초

Synthesis and Electrochemical Study of the Ir(III) Complexes Containing the Diphenyl-quinoline, -Quinoxaline and Pyrazolonate Ligands

  • Lee, Hyun-Shin;Ha, Yun-Kyoung
    • Bulletin of the Korean Chemical Society
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    • 제32권3호
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    • pp.1007-1010
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    • 2011
  • $Ir(dpq/dpqx)_2$(przl-R) complexes were prepared and their electrochemical properties were investigated, where dpq, dpqx and przl-R represent 2,3-diphenylquinoline, 2,3-diphenylquinoxaline and N-phenyl-R-pyrazolonate derivatives, respectively. The iridium complexes containing dpq and dpqx as main ligands were reported to show red phosphorescence, and involvement of a pyrazolonate ancillary ligand in the iridium complexes led to high luminous efficiency for organic light-emitting diodes. In this study, we synthesized red phosphorescent iridium complexes containing a new pyrazolonate ancillary ligand and investigated the HOMOs, LUMOs and resulting electrochemical gaps of $Ir(dpq/dpqx)_2$(przl-R) by cyclic voltammetry. The emission wavelengths of the complexes at 600 - 640 nm were consistent with the gaps of 1.95 - 2.03 eV measured from reduction and oxidation potentials of the complexes.

Silicon Carbide Coating on Graphite and Isotropic C/C Composite by Chemical Vapour Reaction

  • Manocha, L.M.;Patel, Bharat;Manocha, S.
    • Carbon letters
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    • 제8권2호
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    • pp.91-94
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    • 2007
  • The application of Carbon and graphite based materials in unprotected environment is limited to a temperature of $450^{\circ}C$ or so because of their susceptibility to oxidation at this temperature and higher. To over come these obstacles a low cost chemical vapour reaction process (CVR) was developed to give crystalline and high purity SiC coating on graphite and isotropic C/C composite. CVR is most effective carbothermal reduction method for conversation of a few micron of carbon layer to SiC. In the CVR method, a sic conversation layer is formed by reaction between carbon and gaseous reagent silicon monoxide at high temperature. Characterization of SiC coating was carried out using SEM. The other properties studied were hardness density and conversion efficiency.

자외선 조사에 따른 태양전지 보호용 EVA의 열화 (The degradation of EVA for the protection of solar cell by UV-rays irradiation)

  • 김규조;연복희;김승환;김완태;허창수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 하계학술대회 논문집
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    • pp.177-180
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    • 2000
  • We studied the degradation of EVA for the protection of solar cell by UV-rays irradiation. We investigated the reduction of electrical efficiency, photo transmmitance and degradation of EVA by UV-rays irradiation. We utilized the UV irradiation equiped with fluorescent 313nm UV lamp and radiated for 400 hours. For the chemial analysis, we used the UV-vis spectrometer, XPS and examined the degradation mechanism by UV irradiation. It is found that the discolored phenomena, the decrease of photo transmmitance and oxidation reaction is occured by UV irradiation on the EVA sample for the protection of solar cell.

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중첩형 다단전극에 의한 효율적인 전해 이온수 발생 특성 (Effective Electrolytic Water Generation Characteristics by Overlapped Multi-layer Electrode)

  • 신동화;황덕현;정재승;김형표;김진규
    • 조명전기설비학회논문지
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    • 제30권3호
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    • pp.59-64
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    • 2016
  • Applications of electrolytic ion water generated by the oxidation-reduction have gradually been expanded due to their strong sterilizing power and a surface active force. We demonstrate the effect of the multi-layer type electrode for effective ion water generation. The multi-layer type electrode has ability to generate stronger acid and alkali water by increase of the electrode reactive area. Also power consumption efficiency enhances because the electrodes disposed in middle position of the reactive cell raise the usage rate by overlapped effect as an electrolysis electrode.

Polypyrrole Nanotubules의 전기화학적 특성과 리튬 2차전지 정극으로 응용 (Electrochemical Properties of Polypyrrole Nanotubules and it's Application to Lithium Secondary Batteries)

  • 김민성;김현철;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2000년도 추계학술대회 논문집
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    • pp.339-342
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    • 2000
  • Polypyrrole(PPy) nanotubules were formed within template pores by chemical synthesis using $FeCl_3$ as an oxidant. The oxidation peak of PPy nanotubules in the cyclic voltammogram was observed at about 2.8V and 3.3V vs. $Li/Li^+$, while in the case of PPy film, that was observed at about 3.0V. It suggests that the electron hopping on the main chain of PPy nanotubules was improved. When the PPy nanotubules was used to a cathode of lithium secondary battery, we obtained discharge capacity as much as 27 mAh/g, and initial coulomb efficiency by 90%. We expect that the capacity can be improved by further study.

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유도결합형 플라즈마에서의 Ne, Ar, Kr 혼합가스 방전특성 (Inductively Coupled Plasma discharge characteristic of Ne, Ar, Kr mixed gas)

  • 허인성;최용성;이종찬;박대희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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    • pp.306-309
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    • 2004
  • Recently, the environmental problem has received considerable attention. so, many lamps have been developing for environmental requirement and energy efficiency. also, at glow discharge lamp researchers try to reduce energy spending that is power saving lamp. this kind requirement agree with strong points of electrodeless fluorescent lamp has received to now lighting sauce. At low pressure as mTorr I.C.P make high density plasma easily, is good to maintain discharge, has high ionization and does not have failing lighting and losing ability of electron radiation by oxidation and volatilization of electrodes, because this tape does not have electrodes. This point of I.C.P can use at electrodeless fluorescent lamp in this study ICP display elements and Ar, Ne, Kr are researched for optical characteristic. each gas is looked into optical characteristic, also mixed gases is experiment for optical characteristic.

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비만증 -내과적 이해 및 치료- (Obesty - Medical Approach and Treatment -)

  • 오연상
    • 정신신체의학
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    • 제3권2호
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    • pp.197-206
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    • 1995
  • Obesity is a major nutritional problem in the developed countries. The prevalence of obesity may range from 10 to 50 per rent or mort of adult population and it may be increasing tendency. Many efforts have been made to understand the pathogenesis of obesity, but except a few metabolic obesities in the most of obese patients, the mechanisms are not understood. The treatment modalities of obesity, ranging from dietary and pubilc health intervention through the pharmacological and surgical therapy, have been developed and tested. In the obese patients mortalities and mobilities are significantly increased than non obese subjects due to hypertension, diabetics, and other problems. There are four possible mechanisms by which energy balance might be altered to enhance metabolic efficiency. futile metabolic pathway, alteration of protein rum over, alteration in sodium-potassium ATPase and alteration in uncoupled oxidation in brown adipose tissue are considered as possible mechanisms. Low calory and very low calory diets are recommended as a dietary program. Several pharmacological agent such as benzphetamine, fenfluramine, mazindol and fluoxetin are currently popular drugs for the treatment of obesity.

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과산화수소 발생을 위한 전해셀용 양성자 교환 막의 비교 (The comparative study of different membranes for electrolytic cell for the hydrogen peroxide generation)

  • 유선경;김한주;박수길
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 제38회 하계학술대회
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    • pp.1361-1362
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    • 2007
  • There is great interest in the applicability of electrogenerated hydrogen peroxide to a wide variety of industrial processes, usually involving oxidation of organics. Hydrogen peroxide is now employed for the bleaching of mechanical pulp and the bleaching of chemical pulp in the pulp and paper industry, thus displacing the traditional alkaline treatments with chlorine-based chemicals. This psper reperts a comparative study of $H_{2}O_{2}$ electogeneration on gas-diffusion electrode in divided cell with several $Nafion^{(R)}$ protonexchange membranes, Russian cation-exchange membrane MK-40 and SPEEK membrane. The influence of different PEMs on electrochemical cell voltage, current efficiency and energy consumption of hydrogen peroxide electrogeneration has been stadied.

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우수한 기계적 특성과 형상치수 확보를 위한 정밀 압출기술개발 (The Precise Extrusion-Technical Development to Get Excellent Mechanical-property and Accurate Shape- Dimension)

  • 이현철;이광식;오개희;박상우
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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    • pp.311-320
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    • 2009
  • Most advanced countries are researching to apply light weight materials far rolling stock because weight reduction for railway body derives cost-saving, energy-saving, and high-speed. Likewise, current Korea rolling stock field makes arduous effects of weight-reduction, miniaturization, and high-efficiency to achieve a high-speed railway. Aluminum becomes suitable material for these projects because it is much lighter than steel or stainless. Manufacturing the railway car body by using the Aluminum is increasing because Aluminum is not bringing the corrosion by unique oxidation-passivate. Aluminum extrusion profile far railway body requires a high mechanical property, accurate shape dimension, and stable quality because the railway body is composed with many different kinds of extruded profiles. Therefore, it is necessary to research about Aluminum precision-extrusion technology to maintain exit temperature and die load. The goal of this project is applying the Aluminum extrusion profile to next-generation railway car body by developing the Aluminum extrusion profile according to precision-extrusion technology which may maintain isothermal exit temperature.

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Nitrogen removal performance of anammox process with PVA-SA gel bead crosslinked with sodium sulfate as a biomass carrier

  • Tuyen, N.V.;Ryu, J.H.;Yae, J.B.;Kim, H.G.;Hong, S.W.;Ahn, D.H.
    • Journal of Industrial and Engineering Chemistry
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    • 제67권
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    • pp.326-332
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    • 2018
  • In this study,the result shows that polyvinyl alcohol-sodium alginate (PVA-SA) gel bead crosslinked with sodium sulfate are better among the different methods by comparing the relative mechanical strength, mechanical strength swelling and expansion coefficient of beads in water. Subsequently, anammox biomass entrapment by PVA-SA gel was introduced into continuous stirred tank reactor (CSTR). After 24 operation days, the nitrogen removal efficiency achieved 60%, while the nitrogen loading rate (NLR) was $0.14kgN/m^3/d$ and the experiment data indicated that PVA-SA gel bead crosslinked with sodium sulfate can be used to initiate anammox process. Furthermore, it is an alternative for culturing anammox in a long-term operation.