• 제목/요약/키워드: Acceptor concentration

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A novel red light-emitting material and the characteristics of OLEDs using the same as red dopant

  • Lim, Seung-Han;Park, Jung-Hyun;Seo, Ji-Hoon;Ryu, Gweon-Young;Kim, Young-Kwan;Shin, Dong-Myung
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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    • pp.1573-1576
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    • 2007
  • ABCV-Py, a new red fluorescent material, in which two identical electron donor (dimethylamino group) and acceptor (cyano group) moieties are linked to two independent biphenyl groups which share the same core phenyl, has been synthesized for use in OLED application. Performance of red doped electroluminescent devices using ABCV-Py as dopant were measured with various host materials, $Alq_3$, CBP, DPVBi, and p-terphenyl. The performance of device with DPVBi host material was better than those with other host materials and high doping concentration could be applied on device with ABCV-Py as dopant.

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생쥐 췌조직내 Protein Methylase에 대한 자율신경계약물의 영향 (Effect of Adrenergic and Cholinergic Agents on the Activities of Protein Methylases in Pancreatic Tissue)

  • 유태무;박선미;이향우
    • 약학회지
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    • 제35권4호
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    • pp.341-347
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    • 1991
  • It was reported that protein carboxymethylation is involved in amylase secretion of parotid gland by isoproterenot. It was also suggested that a small part of the total cellular protein carboxymethylation is directly involved in pancreatic enzyme secretion. On the contrary, other authors reported that there is no relationship between protein carboxymethylation and secretion in pancreas and parotid gland. In recent study, it was proposed that a methyl acceptor protein plays a limited modulatory role in the coupling of cytosolic $Ca^{++}$ accumulation and exocytosis. In this study, the effects of cholinergic and adrenergic agents on the activities of protein methylase II in pancreatic tissues were examined to test the relationship between protein methylation and pancreatic secretion. The results are as follows. The activity of amylase was slightly increased at the concentration of $10^{-5}$ M of isoproterenol and norepinephrine. The activities of protein methylase I and II were decreased by isoproterenol and norepinephrine, but the activities of protein methylase III were hardly changed. The cholinergic stimulants acetylcholine and carbachol at a concentration of $10^{-5}$ M increased the activities of protein methylase I and decreased the activitiy of protein methylase III compared with control.

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산화구리 나노입자를 혼합한 PEDOT:PSS 박막을 이용한 유기 태양전지 (Organic Solar Cells with CuO Nanoparticles Mixed PEDOT:PSS Buffer Layer)

  • 오상훈;허승진;김현재
    • 한국전기전자재료학회논문지
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    • 제27권2호
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    • pp.121-125
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    • 2014
  • In this research, nanocomposite layers consisting of poly (3,4,-ethylene dioxythiophene):polystyrene sulfonic acid (PEDOT:PSS) and CuO nanoparticles were investigated as hole transport layers in organic solar cells based on poly (3-hexylthiophene) (P3HT) as the electron donor and (6.6) phenyl-C61-butyric acid methyl ester (PCBM) as the electron acceptor. The addition of CuO nanoparticles to PEDOT:PSS layer improved the solar cell performance with 0.5% CuO nanoparticle concentration. At optimized concentration, CuO mixed PEDOT:PSS films had good electrical ($4.131{\Omega}{\cdot}cm$) and optical (transmittance > 90%) properties for using hole transporting layer. We investigated that improved solar cell performance with CuO nanoparticles mixed PEDOT:PSS films.

Photoluminescence property of Al,N-codoped p-type ZnO films by dc magnetron sputtering

  • Jin, Hu-Jie;Liu, Yan-Yan;Park, Bok-Kee;Park, Choon-Bae
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.419-420
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    • 2008
  • In this study, high quality (Al,N)-codoped p-type ZnO thin films were obtained by DC magnetron sputtering. The film on buffer layer grown in 80% $N_2$ ambient shows highest hole concentration of $2.93\times10^{17}cm^{-3}$. The films show hole concentration in the range of $1.5\times10^{15}$ to $2.93\times10^{17}cm^{-3}$, resistivity of 131.2 to 2.864 $\Omega$cm, mobility of 3.99 to 31.6 $cm^2V^{-1}s^{-1}$. The films on Si show easier p-doping in ZnO than those on buffer layer. The film on Si shows the highest quality of optical photoluminescence (PL) characteristics. The donor energy level $(E_d)$ of (Al,N)-codoped ZnO films is about 50 meV and acceptor energy level $(E_a)$ is in the range of 63 to 71 meV. It will help to improve p-type ZnO films.

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Enhancing Factors of Electricity Generation in a Microbial Fuel Cell Using Geobacter sulfurreducens

  • Kim, Mi-Sun;Cha, Jaehwan;Kim, Dong-Hoon
    • Journal of Microbiology and Biotechnology
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    • 제22권10호
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    • pp.1395-1400
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    • 2012
  • In this study, we investigated various cultural and operational factors to enhance electricity generation in a microbial fuel cell (MFC) using Geobacter sulfurreducens. The pure culture of G. sulfurreducens was cultivated using various substrates including acetate, malate, succinate, and butyrate, with fumarate as an electron acceptor. Cell growth was observed only in acetate-fed medium, when the cell concentrations increased 4-fold for 3 days. A high acetate concentration suppressed electricity generation. As the acetate concentration was increased from 5 to 20 mM, the power density dropped from 16 to $13mW/m^2$, whereas the coulombic efficiency (CE) declined by about half. The immobilization of G. sulfurreducens on the anode considerably reduced the enrichment period from 15 to 7 days. Using argon gas to create an anaerobic condition in the anode chamber led to increased pH, and electricity generation subsequently dropped. When the plain carbon paper cathode was replaced by Pt-coated carbon paper (0.5 mg $Pt/cm^2$), the CE increased greatly from 39% to 83%.

탈질조건에서 nitroglycerin의 생물학적 분해 동역학 및 미생물 군집 변화 (Nitroglycerin Biodegradation under Denitrification Conditions and Corresponding Microbial Community Shifts upon Acclimation)

  • 최원철;배범한
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제24권5호
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    • pp.42-54
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    • 2019
  • Biodegradation of an explosive compound, glyceryl trinitrate (GTN), was studied with a denitrifying microbial culture grown in a sequencing batch reactor and a GTN acclimated denitrifying culture. The GTN acclimated culture, which were fed on GTN for 1 month, degraded GTN regioselectively via denitration on C1 position as compared to C2 position denitration by denitrifying culture that has never been exposed to GTN. Accumulation of two isomeric glyceryl dinitrates (GDNs) in both culture medium suggests that GDN denitration is the rate-limiting step in GTN biodegradation. The first order GTN degradation rate normalized to cell concentration of the acclimated culture was calculated to be 0.045 (${\pm}0.002$) L/g-hr. Increasing concentration of electron acceptor(nitrate) resulted in discouraged GTN degradation. According to microbial community analysis, prolonged GTN exposure resulted in 25% increase in the genus level of the GTN acclimated culture with the disappearance of two dominating denitrifying microbial species of Methyloversatilis universalis and Hyphomicrobium zavarzinii in the denitrifying culture.

Synthesis of CuO/ZnO Nanoparticles and Their Application for Photocatalytic Degradation of Lidocaine HCl by the Trial-and-error and Taguchi Methods

  • Giahi, M.;Badalpoor, N.;Habibi, S.;Taghavi, H.
    • Bulletin of the Korean Chemical Society
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    • 제34권7호
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    • pp.2176-2182
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    • 2013
  • A novel sol-gel method was implied to prepare CuO-doped ZnO nanoparticles. XRD and SEM techniques were used to characterize the CuO-doped ZnO sample. The photocatalytic degradation of Lidocaine HCl was investigated by two methods. The degradation was studied under different conditions such as the amount of photocatalyst, pH of the system, initial concentration, presence of electron acceptor, and presence of anions. The results showed that they strongly affected the photocatalytic degradation of Lidocaine HCl. The photodegradation efficiency of drug increased with the increase of the irradiation time. After 6 h irradiation with 400-W mercury lamp, about 93% removal of Lidocaine HCl was achieved. The degree of photodegradation obtained by Taguchi method compatible with the trial-and-error method showed reliable results.

Phospholipase D에 의한 비천연 인지방질의 합성: I. 에멀젼계 내에서의 합성 (Biosynthesis of Unnatural Phospholipids by Phospholipase D: I. Synthesis in A Emulsion System)

  • 정의호;이해익이상영
    • KSBB Journal
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    • 제6권3호
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    • pp.271-279
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    • 1991
  • Phosphatidylglycerol(PG) and two unnatural phospholipids, phosphatidylethyleneglycol (PEG) and phosphatidylpropyleneglycol(PPG), were synthesized from ovolecithin using cabbage phospholipase D(PLD) in a emulsion system. Optimum pH and temperature for the enzymatic synthesis of PG, PEG and PPG in the emulsion system was 5.0-5.6 and 37$^{\circ}C$, respectively. The maximum activity for transphosphatidylation was obtained with 30-80 mM Ca++. Addition of 25% glycerol was required to convert completely ovolecithin to PG, whereas 16% glycerol was sufficient to attain the highest rate of conversion for both PEG and PPG syntheses, the highest conversion rate was obtained with addition of either 10% ethyleneglycol or propyleneglycol. However, the concentration of alcoholic acceptor should be increased up to 20% to improve selectivity up to 100% for PEG or PPG synthesis. Identification of PEG and PPG was made by analyzing the polyvalent alcohols released after their hydrolysis by HCl or PLD.

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분위기와 첨가제가 TiO2 세라믹스의 입자성장에 미치는 영향 (Effects of Additives and Atmospheres on the Grain Growth of TiO2 Ceramics)

  • 박정현;최헌진;박한수
    • 한국세라믹학회지
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    • 제25권4호
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    • pp.390-398
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    • 1988
  • Effects of atmospheres and adidtives on the grain growth of TiO2 ceramics were investigated. In the range of 1300~140$0^{\circ}C$, grain growth was increased in CO2 as compared with O2 atmosphere and the grain boundary migration activation energy was lower than the diffusion activation energy of oxygen ion in TiO2. Also, in the case of addition of oxides, the grain growth was increased by oxides acting as a acceptor andinhibited by oxides acting as a donor. From the above results, when the oxygen vacancy concentration was increased, the intrinsic grain boundary mobility was increased and the pore drag force was decreased due to the rapid densification. Also it seems that the pore was migrated by the surface diffusion rather than lattice diffusion.

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Bioelectrochemical Denitrification by Pseudomonas sp. or Anaerobic Bacterial Consortium

  • Park, Doo-Hyun;Park, Yong-Keun
    • Journal of Microbiology and Biotechnology
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    • 제11권3호
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    • pp.406-411
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    • 2001
  • In a bacterial denitrification test with Pseudomonas sp. and anaerobic consortium, more nitrates and less substrate were consumed but less metabolic nitrite was produced under an anaerobic $H_2$ condition rather than under $N_2$ condition. In a bioelectrochemical denitrification test with the same organisms, the electrochemically reduced neutral red was confirmed to be a substitute electron donor and a reducing power like $H_2$. The biocatalytic activity of membrane-free bacterial extract, membrane fraction, and intact cell for bioelectrochemical denitrification was measured using cyclic voltammetry. When neutral red was used as an electron mediator, the electron transfer from electrode to electron acceptor (nitrate) via neutral red was not observed in the cyclic voltammogram with the membrane-free bacterial extract, but it was confirmed to gradually increase in proportion to the concentration of nitrate in that of the membrane fraction and the intact cell of Pseudomonas sp.

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