• 제목/요약/키워드: Ion Irradiation

검색결과 453건 처리시간 0.032초

IBS법에 의한 BSCCO 박막의 에피택셜 성장 (Epitaxial Growth of BSCCO Films by IBS Method)

  • 양승호;박용필
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2002년도 춘계종합학술대회
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    • pp.627-630
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    • 2002
  • Bi$_2$Sr$_2$CuOx(Bi-2201) thin films were fabricated by atomic layer-by-layer deposition using an ion bean sputtering method. 10 wt% and 90 wt% ozone mired with oxygen were used with ultraviolet light irradiation to assist oxidation. XRD and RHEED investigations revealed that a buffer layer is formed at the early stage of deposition (less than 10 unit cell), and then c-axis oriented Bi-2201 grows on top of it.

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A STUDY OF THE PHOTOTOXICITY OF ORANGE FLOWER ABSOLUTE

  • Yang, Hai-Joo;Lee, Neung-An
    • 대한화장품학회지
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    • 제13권1호
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    • pp.1-6
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    • 1987
  • We have confirmed the phototoxicity of orange flower absolute, studied the phototoxic ingredient and developed a method to eliminate it. To confirm the phototoxicity, we tested French orange flower absolute, Moroccan absolute and Egyptian absolute with Hartley strain guinea Pig under UV irradiation ranging from 320400 nm supplied with fluorescent lamps. Using a combination of isolation techniques including HPLC and IR, we were able to confirm that the phototoxic agent was bergapten. The development of a non-phototoxic orange flower absolute using ion exchange chromatography is described.

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Gas permeation property of organic-inorganic hybrid membrane made by ion-beam irradiation

  • Kawakami, Hiroyoshi
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.90-93
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    • 2004
  • In this study, we have reported an organic-inorganic hybrid membrane, which exhibits an asymmetric structure consisted of a carbonized skin layer and a polyimide porous substructure, to synthesize a novel gas separation membrane combining high gas permeability and selectivity. Both the gas permeability and selectivity of the carbonized layer significantly enhanced when compared with those determined in the control polyimide.

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Irradiation enduced In-plane magnetization in Fe/MgO/Fe/Co multilayers

  • Singh, Jitendra Pal;Lim, Weon Cheol;Song, Jonghan;Kim, Jaeyeoul;Asokan, K.;Chae, Keun Hwa
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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    • pp.188.1-188.1
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    • 2015
  • For present investigation Fe/MgO/Fe/Co multilayer stack is grown on Si substrate using e-beam evaporation in ultrahigh vacuum. This stack is irradiated perpendicularly by 120 MeV $Ag^{8+}$ at different fluences ranging from $1{\times}10^{11}$ to $1{\times}10^{13}ions/cm^2$ in high vacuum using 15UD Pelletron Accelerator at Inter University Accelerator Centre, New Delhi. Magnetic measurements carried out on pre and post irradiated stacks show significant changes in the shape of perpendicular hysteresis which is relevant with previous observation of re-orientation of magnetic moment along the direction of ion trajectory. However increase in plane squareness may be due to the modification of interface structure of stacks. X-ray reflectivity measurements show onset of interface roughness and interface mixing. X-ray diffraction measurements carried out using synchrotron radiation shows amorphous nature of MgO and Co layer in the stack. Peak corresponding body centered Fe [JCPDS-06-0696] is observed in X-ray diffraction pattern of pre and post irradiated stacks. Peak broadening shows granular nature of Fe layer. Estimated crystallite size is $22{\pm}1nm$ for pre-irradiated stack. Crystallite size first increases with irradiation then decreases. Structural quality of these stacks was further studied using transmission electron microscopic measurements. Thickness from these measurements are 54, 36, 23, 58 and 3 nm respectively for MgO, Fe, MgO, Fe+Co and Au layers in the stack. These measurements envisage poor crystallinity of different layers. Interfaces are not clear which indicate mixing at interface. With increase fluence mixing and diffusion was increased in the stack. X-ray absorption spectroscopic measurements carried out on these stacks show changes of Fe valence state after irradiation along with change of O(2p)-metal (3d) hybridized state. Valence state change predicts oxide formation at interface which causes enhanced in-plane magnetization.

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