• 제목/요약/키워드: Pd/Si

검색결과 243건 처리시간 0.037초

PdO 박막의 환원과 환원된 Pd박막의 수소 감지 특성 (A Reduction Process of Palladium Oxide Thin Films and Hydrogen Gas Sensing Properties of Reduced Palladium Thin Films)

  • 이영택;김연주;이준민;조진현;이우영
    • 대한금속재료학회지
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    • 제48권4호
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    • pp.347-352
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    • 2010
  • This study reports a novel method off abricating highly sensitive hydrogen gas sensors based on PdO thin films. The PdO thin films with a thickness of 40 nm were deposited on Si substrates under Ar and $O_2$ ambient conditions using a reactive de magnetron sputtering system. Considerable changes in the resistance of the palladium oxide thin films were observed when they were initially exposed to hydrogen gas, as a result of the reduction process. The sensitivity of the PdO thin films was found to be as high as 90%. After the thin films were exposed to hydrogen gas, the nano-sized cracks were discovered to have formed on the surface of the PdO thin films. These types of nano-cracks that formed on the deoxidized PdO thin films are known to play a key role incausing a four-fold reduction of the response time of the absorption process. The results of this study demonstrate that deoxidized PdO thin films can be applied for use in the creation of high-sensitivity hydrogen sensors.

달의 주기(週期)에 따른 음주(飮酒)와 인성(人性)과의 연관성(聯關性)에 관(關)한 조사연구(調査硏究) (A Study on the correlation between Drinking and MMPI in lunar cycle)

  • 이석준;류영수;류희영
    • 동의신경정신과학회지
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    • 제4권1호
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    • pp.155-164
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    • 1993
  • In this study the author had attempted to establish a correlation among alcohol use and MMPI and lunar cycle. MMPI was carried on 2, April 1992(the last day of the second lunar month) and 15, June 1992(the fifteenth day of the fifth lunar month). These experiments took male and female students who were in WON KWANG University as subjects. The results of it suggested the followings. 1) Drinkers and normal subjects average of T-score in each scales were in a normal scores. 2) In every scales except L,K,Si scales drinkers showed higher scores than normal subjects. There was a significant difference on L, F, Pd, Pa, Sc, Ma scales. 3) On the fifteenth day of the month, drinkers showed Higher T-Scores than normal subjects in every scales excepts L,K,Si scales. There was a significant difference in Ma scale. 4) On the last day of the month, drinkers showed higher T-scores than normal subjects in every scales except L,K,Mf,Si scales. There was a significant difference on L, F, Pd, Sc, Ma scales. 5) Drinkers showed higher than normal subjects in symptom of neurosis and psychosis. As the results of above, human character changes to some extend according to alcohol use. There is a tendency that repeated drinking of college students prone to change into habitual drinking or alcoholic impairment. So controlled drinking among the college students is highly recommended.

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Pd/SiO2-Al2O3 촉매상에서 아크로레인과 암모니아로 부터 피리딘과 β-피콜린의 합성 (Synthesis of Pyridine and β-Picoline from Acrolein and Ammonia on Pd/SiO2-Al2O3 Catalysts)

  • 천승우;최정근;오석연;나석은;박대원
    • 공업화학
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    • 제2권2호
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    • pp.138-146
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    • 1991
  • 실리카-알루미나에 담지된 팔라듐 촉매를 제조하여 아크로레인과 암모니아로부터 피리딘과 ${\beta}$-피콜린의 합성반응에 사용하였다. 시간이 경과함에 따라 촉매표면에 생성된 침적물에 의하여 촉매의 활성이 크게 감소하였다. TPR 실험 결과 이 침적물은 아크로레인과 암모니아의 축합 중합에 의하여 생성됨을 알 수 있었다. 전화율과 피리딘 및 ${\beta}$-피콜린의 생성속도는 아크로레인의 분압이 증가할수록 감소하였다. 침적물의 양과 촉매재생 온도는 아크로레인의 분압에 따라 증가하였으나 암모니아의 분압에는 큰 영향을 받지 않았다.

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Aquaporin 8 Involvement in Human Cervical Cancer SiHa Migration via the EGFR-Erk1/2 Pathway

  • Shi, Yong-Hua;Tuokan, Talaf;Lin, Chen;Chang, Heng
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권15호
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    • pp.6391-6395
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    • 2014
  • Overexpression of aquaporins (AQPs) has been reported in several human cancers. Epidermal growth factor receptor (EGFR)-extracellular signal-regulated kinases 1/2 (Erk1/2) are associated with tumorigenesis and cancer progression and may upregulate AQP expression. In this study, we demonstrated that EGF (epidermal growth factor) induces SiHa cells migration and AQP8 expression. Wound healing results showed that cell migration was increased by 2.79-1.50-fold at 24h and 48h after EGF treatment. AQP8 expression was significantly increased (3.33-fold) at 48h after EGF treatment in SiHa cells. An EGFR kinase inhibitor, PD153035, blocked EGF-induced AQP8 expression and cell migration and AQP8 expression was decreased from 1.59-fold (EGF-treated) to 0.43-fold (PD153035-treated) in SiHa. Furthermore, the MEK (MAPK (mitogen-activated protein kinase)/Erk (extracellular signal regulated kinase)/Erk inhibitor U0126 also inhibited EGF-induced AQP8 expression and cell migration. AQP8 expression was decreased from 1.21-fold (EGF-treated) to 0.43-fold (U0126-treated). Immunofluorescence microscopy further confirmed the results. Collectively, our findings show that EGF induces AQP8 expression and cell migration in human cervical cancer SiHa cells via the EGFR/Erk1/2 signal transduction pathway.