• Title/Summary/Keyword: TFEA

Search Result 16, Processing Time 0.019 seconds

Preparation of novel PVA membranes and their pervaporation properties for esterification membrane reactor of TFEMA (불소화알콜의 에스텔화 막반응기를 위한 새로운 PVA막의 제조와 투과증발특성)

  • 안상만;장봉준;김정훈;이수복;이용택
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 2004.05b
    • /
    • pp.156-159
    • /
    • 2004
  • TFEMA(2,2,2-trifluoroethylmethacrylate)는 광섬유 코팅제, 발수 발유제, 기능성 페인트, 방오가공제, 고분자의 표면개질제 등의 많은 응용제품에 활용되는 단량체로 그 시장규모가 국내에서 600억원, 전 세계에서 8,000억에 해당하는 고부가가치의 화학원료이다. TFEMA는 현재 산촉매하의 8.$0^{\circ}C$의 고온에서 TFEA(2,2,2-trifluoroethaol)와 MA(methacrylic acid)와의 에스텔화 반응으로 제조된다.(중략)

  • PDF

Electro-optical Characterization of Transmission Holographic PDLC with Surfactant

  • Woo, Ju-Yeon;Kim, Eun-Hee;Kim, Byung-Kyu
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.1204-1207
    • /
    • 2004
  • The effects of surfactant on the electro-optic properties of holographic polymer dispersed liquid crystal(HPDLC) have been studied hoping to increase the diffraction efficiency and to reduce the anchoring energy at interfaces. Octanoic acid(OA) was used as sulfactant. The 2,2,2 trifluoroethyl acrylate(TFEA) was added to the monomer mixture to enhance the phase separation and improve optical properties. The morphology of holographic gratings was examined using scanning electron microscopy(SEM). Addition of surfactant was likely to reduce the surface anchoring of the nematic droplet with the polymer surface which favors lowering of the swiching field and to improve the optical qualities.

  • PDF

A Optimization of the ORC for Ship's Power Generation System (해수 온도차를 이용한 선박의 ORC 발전 시스템 최적화)

  • Oh, Cheol;Song, Young-Uk
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.36 no.5
    • /
    • pp.595-602
    • /
    • 2012
  • In this study, for the purpose of reduction of $CO_2$ gas emission and to increase recovery of waste heat from ships, the ORC (Organic Rankine Cycle) is investigated and offered for the conversion of temperature heat to electricity from waste heat energy from ships. Simulation was performed with waste heat from the exhaust gasse which is relatively high temperature and cooling sea water which is relatively low temperature from ships. Various fluid is used for simulation of the ORC system with variable temperature and flow condition and efficiency of system and output power is compared. Finally, 2,400kW output power is obtained by system optimization of the preheater and reheater utilizing waste heat form sea water cooling system.

Transcriptional Regulation of the AP-1 and Nrf2 Target Gene Sulfiredoxin

  • Soriano, Francesc X.;Baxter, Paul;Murray, Lyndsay M.;Sporn, Michael B.;Gillingwater, Thomas H.;Hardingham, Giles E.
    • Molecules and Cells
    • /
    • v.27 no.3
    • /
    • pp.279-282
    • /
    • 2009
  • "Two-cysteine" peroxiredoxins are antioxidant enzymes that exert a cytoprotective effect in many models of oxidative stress. However, under highly oxidizing conditions they can be inactivated through hyperoxidation of their peroxidatic active site cysteine residue. Sulfiredoxin can reverse this hyperoxidation, thus reactivating peroxiredoxins. Here we review recent investigations that have shed further light on sulfiredoxin's role and regulation. Studies have revealed sulfiredoxin to be a dynamically regulated gene whose transcription is induced by a variety of signals and stimuli. Sulfiredoxin expression is regulated by the transcription factor AP-1, which mediates its up-regulation by synaptic activity in neurons, resulting in protection against oxidative stress. Furthermore, sulfiredoxin has been identified as a new member of the family of genes regulated by Nuclear factor erythroid 2-related factor (Nrf2) via a conserved cis-acting antioxidant response element (ARE). As such, sulfiredoxin is likely to contribute to the net antioxidative effect of small molecule activators of Nrf2. As discussed here, the proximal AP-1 site of the sulfiredoxin promoter is embedded within the ARE, as is common with Nrf2 target genes. Other recent studies have shown that sulfiredoxin induction via Nrf2 may form an important part of the protective response to oxidative stress in the lung, preventing peroxiredoxin hyperoxidation and, in certain cases, subsequent degradation. We illustrate here that sulfiredoxin can be rapidly induced in vivo by administration of CDDO-TFEA, a synthetic triterpenoid inducer of endogenous Nrf2, which may offer a way of reversing peroxiredoxin hyperoxidation in vivo following chronic or acute oxidative stress.

A Study on the Ship's ORC Power System using Seawater Temperature Difference (선박의 해수 온도차를 이용한 ORC 발전 시스템에 관한 연구)

  • Oh, Cheol;Song, Young-Uk
    • Journal of Navigation and Port Research
    • /
    • v.36 no.5
    • /
    • pp.349-355
    • /
    • 2012
  • In this study, for the purpose of reduction of $CO_2$ gas emission and to increase recovery of waste heat from ships, the ORC(Organic Rankine Cycle) is investigated and offered for the conversion of temperature heat to electricity from waste heat energy from ships. Simulation is performed with waste heat from the exhaust gasse which is relatively high temperature and cooling sea water which is relatively low temperature from ships. The result shows that 1,000kW power generation is available from exhaust gas and 600kW power generation is available from sea water cooling system. Different fluid is used for simulation of the ORC system with variable temperature and flow condition and efficiency of system and output power is compared.