• Title/Summary/Keyword: H II regions

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Studies on Silk Fibroin Membranes(II) -Adsorption of Acid Dyes in Silk Fibroin Memberane- (Silk Fibroin 막에 관한 연구 (II) -Silk Fibroin 막에 대한 산성염료의 흡착-)

  • 최해욱;박수민;김경환
    • Textile Coloration and Finishing
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    • v.6 no.3
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    • pp.60-66
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    • 1994
  • With the view of studying on the dual adsorption mechanism of acid dyes in connection with the structural difference of silk fibroin, silk fiber and silk fibroin memberane were used for equilibrium dyeing at $60^{\circ}C$, $70^{\circ}C$, $80^{\circ}C$ and pH 3.2, pH 5.0. The dyes used were C.I.Acid Orange 7 and C.I.Acid Red 88 introduced aromatic hydrocabon into Acid Orange 7. From the adsorption isotherm experiment, the total uptake of dyes can be described by Langmuir sorption and Nernst partition. Nernst partition. Nernst partition coefficient $K_1$ decrease of crystalline regions and orientation. The saturation value S of Acid Red 88 were large than total amino group contents and it was attributed it hydrophobic bond. On the other hand, the standard afficity and enthalpy were increased with the in crease of hydrophobic part of dyes. Both $k_1$ and $K_2$ were decreased with the increase of pH, but $k_2$ were more effected than $K_1$.

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IGRINS NIR Spectroscopy of Diffuse Sources around MWC 1080

  • Kim, Il-Joong;Oh, Heeyoung;Jeong, Woong-Seob;Lee, Jae-Joon
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.48.1-48.1
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    • 2019
  • We found a diffuse Hα feature with a large size of ~2' around a Herbig star, MWC 1080. It shows a strong correlation with the elongated outflow cavity centered on the star. To investigate the diffuse Hα source and the molecular cavity in detail, we carried out the high-resolution NIR spectroscopy using IGRINS. We detected six hydrogen Brackett line series, seven H2 lines, and an [Fe II] forbidden line. With the obtained spatial, kinematic, and line ratio results, we discuss the characteristics of the central MWC 1080A, the NE outflow cavity, and the SE molecular cloud regions separately. Most of the bright Brγ sources around MWC 1080A were found to be reflection nebulae, but a point-like Brγ source close to another young star, MWC 1080E, was identified as a distinct source due to MWC 1080E itself. The narrow components of the H2 lines observed around MWC 1080A were found to trace PDRs located on the wall of the main outflow cavity. Based on the shock-excited H2 and [Fe II] lines detected just inside a bow-shock shape Hα feature, we suggest that it represents the actual shock at the head of the NE outflow from MWC 1080A. Also, we newly detected the shock-excited H2 and [Fe II] lines with highly blueshifted velocities in the SE molecular cloud region. They could be related to unrevealed outflows from other young stars existing around MWC 1080A.

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Bonding and Antibonding Regions (II). Origin of Barriers to Internal Rotation of $H_2O_2$ and $C_2H_6$ (결합공간과 반결합공간 (제2보). $H_2O_2$$C_2H_6$의 Internal Rotation Barrier의 원천적 요인)

  • Kim Hojing;Lee Duckhwan
    • Journal of the Korean Chemical Society
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    • v.23 no.1
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    • pp.20-29
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    • 1979
  • The origin of barriers to internal rotation of hydrogen peroxide and ethane is investigated by using the concept of Bonding and Antibonding Regions. The strong bond formations between the axial and end atoms on the same side make the real charge densities in these molecules less dependent on conformations than those in the hypothetical molecules having no axial atoms. Thus, the existence of the axial atoms should induce the migration of the transition density from the Bonding region to the Antibonding region. Barrier to internal rotation can be understood in terms of this migration of the transition density to such an extent that the change in nuclear-nuclear repulsion energy becomes the dominating part of the total perturbation energy.

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Near-Infrared Spectra of Super Star Clusters in M82

  • Nguyen, Kim Ngan N.;Pak, Soo-Jong;Im, Myung-Shin;Ho, Luis C.
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.61.2-61.2
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    • 2012
  • We observed selected super cluster regions in M82 with 5'5 arcsec field-of-view using near-IR high resolution echelle spectrometer, IRCS, at the SUBARU 8.2 m telescope. The slit width of 0.15 arcsec makes the high resolution (R ${\approx}$ 20,000) spectra in the H and K bands. In this poster, we present sample spectra of [FeII] lines and ro-vibration lines of $H_2$ which trace ionic shocks in the intercloud regions and molecular shocks. The line widths of $Br{\gamma}$ line are also measured to derive the velocity dispersion within the super star clusters.

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High-Resolution Observations of the Molecular Clouds Associated with the Huge H II Region CTB 102 (거대 수소 이온화 영역 CTB 102와 연관된 분자운의 고분해능 관측)

  • Kang, Sung-Ju;Marshall, Brandon;Kerton, C.R.;Kim, Youngsik;Choi, Minho;Kang, Miju
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.71.1-71.1
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    • 2019
  • We report the first high-resolution (sub-arcminute) large-scale mapping $^{12}CO$ and $^{13}CO$ observations of the molecular clouds associated with the giant outer Galaxy H II region CTB 102 (KR 1). These observations were made using a newly commissioned receiver on the 13.7-m radio telescope at the Taeduk Radio astronomy Observatory (TRAO). Our observations show that the molecular clouds have a spatial extent of $60{\times}35pc$ and a total mass of $10^{4.8}-10^{5.0}$ solar mass, Infrared data from WISE and 2MASS were used to identify and classify the YSO population associated with ongoing star formation activity within the molecular clouds. Moving away from the H II region, there is an age/class gradient consistent with sequential star formation. The infrared and molecular line data were combined to estimate the star formation efficiency (SFE) of the entire cloud as well as the SFE for various sub regions of the cloud.

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Development of Prediction Model for Sidewall Curl in Sheet Meta1 Forming(II)-Experimental Validation (박판성형시 컬 예측모델 개발(II)-실험적 검증)

  • Joo, B.D.;Park, H.K.;Kim, D.W.;Moon, Y.H.
    • Transactions of Materials Processing
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    • v.16 no.6
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    • pp.438-442
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    • 2007
  • Sidewall curl is the curvature that results from non-uniform through-thickness strain present in the sheet stamping process which involves material flow over a die radius. In order to understand and control curl for tight fit-up tolerances, an analytical model that can provide a reliable measure for the amount of curl would be very helpful. In this study, a model is developed based on the moment-curvature relationship during bending-under-tension operations. For the verification of analytical model, sidewall curl is experimentally measured after deformation of a strip using a bending-under-tension test system. The results show a consistent relationship between the theoretically predicted value and the experimentally obtained one, especially in regions of high curl.

CHEMICAL ABUNDANCE ANALYSIS OF M31 AND M33 BASED ON THE SPECTRUM OF HII REGIONS (HII 영역 분광자료를 통한 M31과 M33의 화학원소 결정)

  • HAN SOO RYEON;HYUNG SIEK;PARK HONG-SUH;LEE WOO-BAlK
    • Journal of The Korean Astronomical Society
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    • v.34 no.2
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    • pp.67-80
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    • 2001
  • Chemical evolution of galaxies can be understood by studying the spatial distribution of heavy elements. We selected two nearby galaxies, M31 and M33 and investigated spectrum of their HII regions: a) the elec-tron densities have been derived from the [S II] 6717/6731 ratio along with the most recent atomic constants (Hyung & Aller 1996); b) the electron temperatures were determinated from the Pagel's empirical method. Nebula Model (Hyung 1994) has been employed to predict the spectral line intensities which gives the proper chemical abundances. The model would predict the line intensities correctly only when various input parameters such as the effective central star temperatures, gravity log g, model atmosphere as well as the geometry and the nebula physical condition are appropriate. Thus, the determination of chemical abundances of O, S, N of the two nearby galaxies M31 and M33 has been done, which shows a radial dependance of O/H and N/H: decrease with the distance, or increasing electron temperature due to the elemental deficiency. Abundances of M31 appear to be enhanced than those of M33.

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Cloning of hadA-like Sigma Factor Gene from Streptomyces coelicolor A3(2) (Streptomyces coelicolor A3(2)에서 hrdA유사 Sigma 인자 유전자의 클로닝)

  • Hahn, Ji-Sook;Cho, Eun-Jung;Roe, Jung-Hye
    • Korean Journal of Microbiology
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    • v.32 no.4
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    • pp.264-270
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    • 1994
  • A gene coding for a novel putative $\sigma$ factor of RNA polymerase has been identified from Streptomyces coelicolor A3(2) using Escherichia coli rpoS gene fragment as a probe. The 486 bp rpoS gene fragment was amplified from E. coli genomic DNA by PCR with two synthetic oligonucleotides, the sequences of which were deduced from the amino acid sequences in the regions 2.3 and 4.2 conserved among various bacterial factors. When E. coli genomic DNA fragments were hybridized with cloned rpoS probe, only one band corresponding to rpoS gene (3.2 kb PvuII fragment or 2.3 kb KpnI fragment) was detected. In S. coelicolor, however, two bands were detected both in PvuII digested DNA and SalI digested DNA. 3.5 kb PvuII fragment which binds the rpoS gene probe was cloned (pMS1) from the sublibrary, and the nucleotide sequences of 1.0 kb BamH'/HincII subclone (pBH2) was partially determined. The nucleotide sequences revealed extensive similarity to other $\sigma$ factor genes of S. coelicolor (hrdA, hrdB, hrdC, hrdD), S. aureofaciens (hrdA, hrdB, hrdC, hrdD), Synechococcus species, Pseudomonas aeruginosa, Stigmatella aurantiaca, and Anabaena species. The nucleotide sequences in regions 1.2 and 4 were compared with the corresponding regions of 5 known ${\sigma}$ factor genes of S. coelicolor by multiple alignment. It turned out that the cloned gene is most closely related to hrdA showing 88% amino acid similarity in region 1.2 and 75% in region 4.

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The Distribution of Regional Unusual Temperature Korea (한국의 지역별 이상기온의 분포 특성과 그 지역구분)

  • Heo, In-Hye
    • Journal of the Korean association of regional geographers
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    • v.12 no.4
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    • pp.461-474
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    • 2006
  • This paper aims to analyze regional characteristics of unusual temperature events on summer and winter. The major data used in this study are the daily mean temperature of summer (June-August) and winter (December-February) and wind field on 850 hPa height. Regions of unusual temperature are divided into five regions by the monthly frequency of unusual temperature occurrence. The divided regions are following as: the middle east coastal region (I) where the summer unusual high temperature occurrence frequency is highest; the Gyunggi west coastal and northern middle inland region (II) where winter unusual low temperature occurrence frequency is highest and winter unusual high temperature occurrence frequency is low; the western middle and south region (III) where unusual temperature occurrence ratio is not concentrated on specific season; the forest and southern east region (IV) where unusual high temperature is low; and the south coastal and Jeju island region (V) where winter unusual high temperature is highest.

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INTENSITY RATIO OF [O I] λ6300 AND Hα IN COLLISIONAL IONIZATION EQUILIBRIUM (충돌이온화평형 상태에서 [O I] λ6300과 Hα의 세기비)

  • SEON KWANG-IL;LEE DAE-HEE
    • Publications of The Korean Astronomical Society
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    • v.19 no.1
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    • pp.17-20
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    • 2004
  • In this paper, the intensity ratio of [O I] $\lambda6300$ and $H_\alpha$ lines, which plays an important role in the study of warm (or diffuse) ionized interstellar medium, is calculated assuming collisional ionization equilibrium (or coronal equilibrium). The calculated ratio is compared with the previous works, and with the observations, obtained by Reynolds (1989) and Reynolds et al. (1998) with the Wisconsin Ha Mapper facility, toward the directions that sample the faint interstellar emission-line background. The comparison confirms that most of the Ha originates from nearly fully ionized regions along the lines of sight rather than from partially ionized H I clouds or layers of H II on the surfaces of H I clouds.