• 제목/요약/키워드: Optical Probe

검색결과 598건 처리시간 0.022초

Structure and Physical Conditions in MHD Jets from Young Stars

  • SHANG HSIEN
    • 천문학회지
    • /
    • 제34권4호
    • /
    • pp.297-299
    • /
    • 2001
  • We have constructed the foundations to a series of theoretical diagnostic methods to probe the jet phenomenon in young stars as observed at various optical forbidden lines. We calculate and model in a self-consistent manner the physical and radiative processes which arise within an inner disk-wind driven magneto centrifugally from the circumstellar accretion disk of a young sun-like star. Comparing with real data taken at high angular resolution, our approach will provide the basis of systematic diagnostics for jets and their related young stellar objects, to attest the emission mechanisms of such phenomena. This work can help bring first-principle theoretical predictions to confront actual multi-wavelength observations, and will bridge the link between many very sophiscated numerical simulations and observational data. Analysis methods discussed here are immediately applicable to new high-resolution data obtained with HST and Adaptic Optics.

  • PDF

Application of Optical Method for Quantitative Investigation of MgO Erosion in AC-PDP

  • Choi, Seung-Ho;Lee, Soon-Il;Oh, Soo-Ghee;SunWoo, Jin-Ho;Kim, Jae-Gak;Lee, Gol-Hee;Kim, June-Dong
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
    • /
    • pp.185-186
    • /
    • 2000
  • For the quantitative investigation of the erosion of MgO layers in real ac-PDP cells, we constructed a microscopic spectrophotometer which is capable of measuring transmission spectra from the area as small as 20 ${\times}$ 20 ${\mu}m^2$. In the test on the sputtered MgO films with a thickness gradient, we were able to probe the thickness variation of 1000 nm over $1000-{\mu}m$ distance. Using this instrument, we were able to determine not only the erosion rate at the particular position of ac-PDP cells but also the relative erosion rate at different positions in a single ac-PDP cell.

  • PDF

평판형 광원에서 제논(Xe) 플라즈마의 전기적 광학적 특성 연구 (The electrical and optical properties of Xe plasma in flat lamp)

  • 백광현;양종경;이종찬;최용성;박대희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 춘계학술대회 논문집
    • /
    • pp.60-64
    • /
    • 2005
  • Discharge of the flat lamp lighting source research are requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important, distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp, we tested the discharge from 100 Torr to 300 Torr pressure, the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

  • PDF

팔공산 화강암내 흑운모의 풍화과정에서 생성되는 고령토광물들의 광물학적 특성 및 생성 환경 (Mineralogical Characteristics and Formation Environment of Kaolin Minerals in the Weathering of Granitoids: Weathering of Biotite in Palgongsan Granite)

  • 정기영
    • 한국광물학회지
    • /
    • 제11권2호
    • /
    • pp.97-105
    • /
    • 1998
  • Weathering of biotite in Palgonsan granite was studied by using X-ray diffraction, optical microscopy, scanning electron microscopy, and electron probe micro analysis. Biotite altered to biotite/vermiculite regular mixed layer mineral (B/V) in the early stage of weathering. Although partially replaced by kaolinite with the progress of weathering. B/V is the major weathering product of biotite throughout the profile. During the formation of B/V, Mg, Fe and K are removed from a biotite layer to form a vermiculite layer by about 28%, 44% and 88%, respectively, whereas the Ti content is not changed. Considerable volume increase after the kaolinitization of B/V suggests that Al and Si are largely introduced from the external weathering solution. The silicate lattice templet of a weathering biotite facilitated the nucleation and growth of kaolinite. In the Palgongsan granite weathering profile, plagioclase weathered mostly into halloysite whereas biotite greatly contributes to the kaolinite crystallization though its small content in fresh rock.

  • PDF

석출강화형 Ni 기 초내열합금의 천이액상확산접합 (Transient Liquid Phase Bonding of Gamma Prime Precipitation Strengthened Ni Based Superalloy)

  • 김정길;박해지;심덕남
    • Journal of Welding and Joining
    • /
    • 제35권3호
    • /
    • pp.52-61
    • /
    • 2017
  • Transient liquid phase (TLP) bonding is essential technology to repair micro-cracking on the airfoil of blades and vanes for gas turbines. Understanding of the characteristics of TLP bonding of the superalloys is necessary in the application of the technology for repairing these components. In this study, the focus was on investigating TLP bonding characteristics of ${\gamma}^{\prime}$ precipitation strengthened Ni based superalloy. TLP bonding was carried out with an amorphous filler metal in various bonding conditions, and the microstructural characterization was investigated through optical microscopy (OM) and electron probe micro-analysis (EPMA). The experimantal results explained clearly that bonding temperatures had critical effects on the TLP bonding behaviors, and that isothermal solidication of the joints made at higher temperatures than $1170^{\circ}C$ was controlled by Ti diffusion instead of B.

다양한 기판에 제작한 ITO 박막의 실온 특성 변화 (Properties of ITO thin film's aging change prepared on the various substrate)

  • 김상모;임유승;손인환;김경환
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
    • /
    • pp.403-404
    • /
    • 2008
  • In this study, we prepared ITO thin film on glass, polycarbonate (PC) and polyethersulfone (PES) substrate in Facing Targets sputtering (FTS) system. Properties of as-deposited thin films's aging change were investigated as a function of time placed in the air. The electrical and optical properties of as-deposited thin films were employed by a four point probe and an UV/VIS spectrometer, an X-ray diffractometer (XRD), a Field Emission Scanning Electron Microscope(FESEM) and a Hall Effect measurement. As a result, as time went by, transmittance of all films did not change but resistivity of films was decreasing.

  • PDF

MOLECULAR GAS PROPERTIES UNDER ICM PRESSURE IN THE CLUSTER ENVIRONMENT

  • LEE, BUMHYUN;CHUNG, AEREE
    • 천문학논총
    • /
    • 제30권2호
    • /
    • pp.491-494
    • /
    • 2015
  • We present 12CO (2-1) data for four spiral galaxies (NGC 4330, NGC 4402, NGC 4522, NGC 4569) in the Virgo cluster that are undergoing different ram pressure stages. The goal is to probe the detailed molecular gas properties under strong intra-cluster medium (ICM) pressure using high-resolution millimeter data taken with the Submillimeter Array (SMA). Combining this with Institut de RadioAstronomie $Millim{\acute{e}}trique$ (IRAM) data, we also study spatially resolved temperature and density distributions of the molecular gas. Comparing with multi-wavelength data (optical, $H\small{I}$, UV, $H{\alpha}$), we discuss how molecular gas properties and star formation activity change when a galaxy experiences $H\small{I}$ stripping. This study suggests that ICM pressure can modify the physical and chemical properties of the molecular gas significantly even if stripping does not take place. We discuss how this affects the star formation rate and galaxy evolution in the cluster environment.

평판형 광원에서 제논 플라즈마의 전기적 및 광학적 특성 (Electrical and Optical Properties of Xe Plasma in Flat Lamp)

  • 최용성;이경섭
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 광주전남지부
    • /
    • pp.71-74
    • /
    • 2006
  • Discharge of the flat lamp lighting source research arc requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp. we tested the discharge from 100 Torr to 300 Torr pressure. the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

  • PDF

제논(Xe) 가스를 사용한 평판형 광원에서의 전기 및 광학적 특성 연구 (Electrical and Optical properties of Xe gas in flat lighting source)

  • 백광현;양종경;이종찬;최용성;박대희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
    • /
    • pp.2190-2192
    • /
    • 2005
  • Discharge of the flat lamp lighting source research are requested very much. For improving brightness, life time, efficiency of flat lamp, plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. distance of discharge electrode is 5.5mm and width is 16.5mm, we measured electron temperature and electron density measured with single langmuir probe in flat lamp. we tested the discharge from 100 Torr to 300 Torr pressure. the Pulse is rectangular pulse with frequency 20kHz and Duty ratio 20%. Resultly, electron temperature decreases and electron density increase as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.

  • PDF

디스플레이용 투명전도막(AZO)의 제작 (Transparent Conductive Oxide(TCO) thin film(AZO) prepared for display application)

  • 김현웅;금민종;손인환;신성권;가출현;김경환
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.1
    • /
    • pp.165-168
    • /
    • 2004
  • In this study, AZO(ZnO:Al) thin film were prepared by FTS(Facing Target Sputtering) system. The electrical, optical and crystallographic properties of AZO thin film with $O_2$ gas flow ratio have been investigated. The thickness, transmittance, crystal structure and resistivity of AZO thin film were measured by a-step, UV-VIS spectrometer, XRD and four-point probe, respectively. As a result AZO thin film deposited with the transmittance over 80% and the resistivity about $10^{-1}\Omega-cm$.

  • PDF