• Title/Summary/Keyword: absorption line

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SMALL-SCALE Hα DYNAMIC FEATURES SUPPORTED BY CHROMO SPHERIC MAGNETIC RECONNECTION

  • LEE SANGWOO;YUN HONG SIK;CHAE JONGCHUL;GOODE PHILIP R.
    • Journal of The Korean Astronomical Society
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    • v.36 no.spc1
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    • pp.21-27
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    • 2003
  • In the present study, we have investigated morphology and evolution of small-scale Ha dynamic features on the quiet sun by analyzing video magnetograms and high resolution Ha images simultaneously taken for 5 hours at Big Bear Solar Observatory on April 18, 1997. From comparisons between time sequential longitudinal magnetograms and H$\alpha$ images covering $150" {\times} 150"$, several small-scale H$\alpha$ dynamic features have been observed at a site of magnetic flux cancellation. A close relationship between such features and cancelling magnetic fluxes has been revealed temporarily and spatially. Our results support that material injection by chromospheric magnetic reconnect ion may be essential in supporting numerous small-scale H$\alpha$ dynamical absorption features, being in line with recent observational studies showing that material injection by chromospheric magnetic reconnect ion is essential for the formation of solar filaments.

Constraining the MBH-${\sigma}*$ relation of the NLS1s using a directly measured stellar velocity dispersion

  • Yoon, Yosep;Woo, Jong-Hak
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.46.1-46.1
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    • 2013
  • WIth high accretion rate and low black hole mass, narrow line seyfert 1 galaxies (NLS1s) are an interesting sub-class of AGNs. To investigate whether NLS1s follow the same M-${\sigma}*$ relation as other AGNs, we selected a sample of 110 NLS1s at relatively low redshift z < 0.1 from SDSS DR7 by constraining the FWHM of Ha broad component, and determined their black hole masses. We measured stellar velocity dispersion of 65 objects which showed strong enough stellar lines in the SDSS spectra, while we adopted the ${\sigma}*$ measurements of 45 objects from Xiao et al. 2011. We find that NLS1s follow the M-${\sigma}*$ relation of active and inactive galaxies while there is a dependency due to the galaxy inclination, which probably cause rotational broadening of stellar absorption lines.

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Production of Shikonin by A Hairy Root Culture of Lithospermum erythrorhizon

  • Seo, Weon-Taek;Park, Young-Hoon;Choe, Tae-Boo
    • Journal of Microbiology and Biotechnology
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    • v.2 no.1
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    • pp.41-45
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    • 1992
  • Shikonin production was examined in a bubble column bioreactor system with the hairy roots of Lithosphermum erythrorhizon. The volumetric productivity was higher than those obtained from other reactor configurations with free or immobilized cells of the same cell line. The productivities of the bubble column reactor, with and without a product absorption trap, were 7.4 and 4.5 mg of shikonin/l/d, respectively. This indicated the importance of the product removal in the design and operation of the shikonin production system with hairy root culture.

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Environmental Noise Prediction of Power Plants (발전소 환경소음 예측)

  • 조대승;유병호
    • Journal of KSNVE
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    • v.7 no.4
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    • pp.621-629
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    • 1997
  • For computer aided design and costruction of low noisy power plants, indoor and outdoor noise prediction program has been developed. The program utilizes the predefined data of noise sources and building materials and has the faculty to estimate the source level using the empirical formula in case of the measured data not being available. In the noise prediction, the mutual noise propagation between indoor and outdoor sites are considered. The outdoor noise source in the calculation of geometric divergence effects is modelled as the omni-directional finite line or planar source according to the source geometry and the receiving points. Outdoor noise prediction is carried out to consider the diffraction effect due to plant structures as well as the attenuation effect due to atmospheric absorption and soft ground. The results of indoor and outdoor noise prediction for a recently constructed diesel engine power plant show good agreement with the measured.

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Study of Transient Response in Non-uniform Plasma Layer with Optically-Controlled Microwave Pulses (광-마이크로파 기반 유도플라즈마의 과도응답 특성에 관한 연구)

  • Wang, Xue;Choi, Yue-Soon;Park, Jong-Goo;Kim, Yong-K.
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.6
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    • pp.1174-1179
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    • 2009
  • In this paper we develop the characteristic of density on non-uniform plasma in different layer of the semiconductor with optically controlled microwave pulses. The transient response of the microwave pulses in different plasma layer has been evaluated by calculating the variation of the reflection function of dielectric microstrip lines. The lines has used under open-ended termination containing optically induced plasma region, which has illuminated a laser source. The characteristics impedances resulting from the presence of plasma are evaluated by the transmission line model. The analyzes the variation of transient response in a 0.01cm layer near the surface for frequency range from 1GHz to 128GHz. The diffusion length LD is larger than compared to the absorption depth $l/_{\alpha}l$. The variation of characteristic response in plasma layer with microwave pulses which has in deferentially localized has been evaluated analytically.

Carrier-Mediated Tissue Distribution and Blood-Brain Barrier Transport of New Quinolones

  • Tsuji, Akira
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1997.04a
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    • pp.57-63
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    • 1997
  • Animal and clinical investigations have shown that fluoroquinolones, new quinolone antibacterial agents (NQs), are well absorbed across the intestinal tract, with a bioavailability of 60-90% after oral administration. Although some types of carrier-mediated intestinal transport mechanisms have been reported for enoxacin (ENX), ofloxacin (OFLX) and sparfloxacin (SPFX), recent results using a human intestinal epithelial cell line, Caco-2, indicated a passive or nonsaturable transport of SPFX, one of the most hydrophobic NQs. The mechanism underlying the intestinal absorption of NQs is still largely unknown. The distribution of NQs into peripheral tissues including erythrocytes is very rapid and their tissue-to-plasma concentration ratios (Kp) are considerably larger than those of inulin (an extracellular fluid space marker), in spite of almost complete ionization of NQs at the physiological pH. Our findings suggest that OFLX and lomefloxacin (LFLX) are taken up by rat erythrocytes via a transport system common to that of a water-soluble vitamin, nicotinic acid.

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Electronic Spectroscopy and Ligand Field Analysis of mer-Chloro(1,2-ethanediamine)(1,5,9-triazanonane)chromium(III) Tetrachlorzincate(II)

  • Park, Jong-Ha;Park, Yu-Chul;Kim, Hag-Sung
    • Journal of Photoscience
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    • v.7 no.3
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    • pp.97-101
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    • 2000
  • The 77 K emission and excitation spectra, and 298 K infrared and absorption spectra of mer-[CrCl(en)(dpt)]ZnCl$_4$(en=1,2-diaminoethane; dpt=1,5,9-triazanonane) have been measured. Ligand field electronic transitions due to spin-allowed and spin-forbidden are assigned. The zero-phonon line in the excitation spectrum splits into two components by 151$cm^{-1}$ /, and large$^2$E$^{g}$ splitting can be reproduced by the modern ligand field theory. It is confirmed that nitrogen atoms of the en and dpt ligands have a strong $\delta$-donor character, but chloride ligand has weak $\delta$-and $\pi$-donor properties toward chromium(III) ion.

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Does Agitation Condition Affect the Correlation Between in vitro Permeability of Xenobiotics across Caco-2 Cells and in vivo Bioavailability of the Compounds\ulcorner

  • Yoo, Ho-Jung;Kim, In-Wha;Hong, Soon-Sun;Chung, Suk-Jae;Shim, Chang-Koo
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.419.2-420
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    • 2002
  • Caco-2 is a cell line derived from the human colon adenocarcinoma and often used as a model for studying intestinal drug absorption. It has been well-known that a strong correlation holds between in vitro permeability across Caco-2 cell monolayers and in vivo bioavailability for various drugs. but the correlation curves varied depending on laboratories. The permeabilities of drugs across Caco-2 cell monolayers have been measured under different agitation conditions. (omitted)

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A Study on the Three-Dimensional Heat Flow Analysis in the Laser Welding for Deep Penetration (레이저 심 용입 용저에서 3차원 열유동 해석에 관한 연구)

  • 이규태;김재웅
    • Journal of Welding and Joining
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    • v.18 no.3
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    • pp.76-82
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    • 2000
  • In this study, three-dimensional heat flow in laser beam welding for deep penetration was analyzed by using F.E.M common code, and then the results were compared with the experimental data. The models for analysis are full penetration welds and are made at three different laser powers (6, 9.9, 4.5 kW) with two different welding speeds (5.8mm/s, 5mm/s). The characteristics of thermal absorption by the workpiece during deep penetration laser welding can be represented by a combination of line heat source through the workpiece and distributed heat source at the top surface due to the plasma plume above the top surface. This gives an insight into the way in which the beam interacts with the material being welded. The analyses performed with the combined heat source models show comparatively good agreement between the experimental and calculated melt temperature isotherm, i.e, the fusion zone boundary. The results are used to explain the "nail head" appearance of fusion zone, which is quite common in laser beam welds.eam welds.

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SPECTROSCOPIC STUDIES IN X-RAY ASTRONOMY (X-선 천문 분야의 분광관측 연구)

  • CHOI CHUL-SUNG
    • Publications of The Korean Astronomical Society
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    • v.15 no.spc1
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    • pp.73-83
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    • 2000
  • X-ray astronomy deals with measurements of the electromagnetic radiation in the energy range of $E\~0.1-100 keV (\lambda\~0.12-120{\AA})$. The wavelength of X-ray is comparable to the size of atoms, so that the photons in the X-ray range are usually produced and absorbed by the atomic processes. Since the launch of the first X-ray astronomy satellite 'Uhuru' in 1970, technological advances in a launch capability and a detection capability make X-ray astronomy one of the most rapidly evolving fields of astronomical research. Particularly, a spectral resolving power $E/{\Delta}E$ has been increased by an order of 2 - 3 (in the energy range of 0.1 - 10 keV) during the past 30years. In this paper, I briefly review a developing process of the resolving power and spectroscopic techniques. Then I describe important emission/absorption lines in X-ray astronomy, as well as diagnostics of gas property with line parameters.

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