• 제목/요약/키워드: $A_2B_2O_7$ crystal and poly crystal

검색결과 2건 처리시간 0.019초

$A_2B_2O_7$계를 중심으로 한 고온용 압전체의 개발동향 (The recent trend of $A_2B_2O_7$ piezoelectric ceramics having high curie temperature)

  • 남효덕
    • E2M - 전기 전자와 첨단 소재
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    • 제9권4호
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    • pp.415-421
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    • 1996
  • 본 고에서는 고온센서용 압전체가 필요하고 실용화할 수 있는 다결정 압전세라믹스 및 박막재료가 요구되는 점을 감안하여 고온에서도 사용할 수 있는 단결정 $A_{2}$B$_{2}$O$_{2}$형의 성장과 그 전기적 특성 및 최근 개발을 시도하고 있는 다결정 $A_{2}$B$_{2}$O$_{2}$형 압전체에 대한 지금까지의 개발동향을 문헌소개와 함께 필자의 연구결과 일부도 보고하며 아울러 박막화의 가능성도 제시하고자 한다.

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진무탕(眞武湯)이 $H_2O_2$로 유도된 C6 Glial 세포사에 미치는 영향 (Protective Effect of Jinmu-tang on $H_2O_2$-induced Cell Death in C6 Glial Cells)

  • 최정훈;신용진;하예진;조문영;유주연;이숭인;신선호
    • 대한한방내과학회지
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    • 제33권3호
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    • pp.272-283
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    • 2012
  • Objectives : The purpose of this study was to investigate the mechanism of protective effect of Jinmu-tang (JMT, Zhenwu-tang) extract on $H_2O_2$-induced cell death in C6 glial cells. Methods : Cultured C6 glial cells of white mice were pretreated with JMT extract and exposed to $H_2O_2$ for inducing cell death. We measure the cell viability by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and investigate the cell morphology using a light microscope after crystal violet (CV) staining. Reactive oxygen species (ROS) formation was analyzed using a flow cytometer and a fluorescent microscope after staining with 2'7'-dichlorofluorescein diacetate (DCF-DA). DNA fragmentation was analyzed using a flow cytometer after propidium iodide (PI) staining and nuclei morphology was investigated using a fluorescent microscope after 2-[4-amidinophenyl]-6-indo-lecarbamidine dihydrochloride (DAPI) staining. We analyzed expression of Bax, processing of procaspase-3 and poly (ADP-ribose) polymerase (PARP), and activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) by western blot method. Tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) secretion was analyzed using Quantikine kit. Results : We determined the elevated cell viability by JMT extract on $H_2O_2$-induced C6 glial cell death. ROS formation, DNA fragmentation, $I{\kappa}B{\alpha}$ phosphorylation, NF-${\kappa}B$ activation, and secretion of TNF-${\alpha}$ induced by $H_2O_2$ are inhibited by JMT extract pre-treatment. JMT extract inhibits Bax expression, processing of caspase-3 and PARP that are critical biochemical markers of apoptotic cell death. Conclusions : These results suggest that JMT extract has a protective effect on $H_2O_2$-induced C6 glial cell death in various pathways.