• Title/Summary/Keyword: Dust sample

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2 - 5 μm Spectroscopy of Red Point Sources in the Galactic Center

  • Jang, DaJeong;An, Deokkeun;Sellgren, Kris;Ramirez, Solange V.
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.67.4-67.4
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    • 2019
  • We present preliminary results of our long-term (2009-2017) observing campaign using the NASA IRTF at Mauna Kea, to obtain $2-5{\mu}m$ spectroscopy of ~200 red point sources in the line of sight to the Galactic center. Point sources in our sample were selected from the mid-infrared images of the Spitzer Space telescope, and include candidate massive young stellar objects, which have previously been identified from our Spitzer/IRS spectroscopy. We show high foreground extinction of these sources from deep $3.1{\mu}m$ H2O ice and aliphatic hydrocarbon absorption features, suggesting that they are likely located in the central 300 pc region of the Galactic center. While many sources reveal photospheric $2.3{\mu}m$ gas CO absorption, few of them clearly indicate $3.54{\mu}m$ CH3OH ice absorption, possibly indicating a large dust column density intrinsic to a massive young stellar object.

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GALAXY SED FITTING FROM AKARI TO HERSCHEL: 0.7 < z < 4 SUB-MILLIMETER LYMAN BREAK GALAXIES IN INFRARED

  • Burgarella, D.;The PEP-HerMES-COSMOS team, The PEP-HerMES-COSMOS team
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.311-316
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    • 2012
  • Lyman break Galaxies are galaxies selected in the rest-frame ultraviolet. But, one important and missing information for these Lyman break galaxies is the amount of dust attenuation. This is crucial to estimate the total star formation rate of this class of objects and, ultimately, the cosmic star formation density. AKARI, Spitzer and Herschel are therefore the major facilities that could provide us with this information. As part of the Herschel Multi-tiered Extragalactic Survey, we have began investigating the rest-frame far-infrared properties of a sample of more than 4,800 Lyman Break Galaxies in the GOODS-North fiels. Most LBGs are not detected individually, but we do detect a sub-sample of 12 objects at 0.7 < z <1.6 and one object at z = 2.0. The ones detected by Herschel SPIRE have redder observed NUV-U and U-R colors than the others, while the undetected ones have colors consistent with average LBGs at z > 2.5. We have analysed their UV-to-FIR spectral energy distributions using the code cigale to estimate their physical parameters. We find that LBGs detected by SPIRE are high mass, luminous infrared galaxies. They also appear to be located in a triangle-shaped region in the $A_{FUV}$ vs. $logL_{FUV}$ diagram limited by $A_{FUV}$ = 0 at the bottom and by a diagonal following the temporal evolution of the most massive galaxies from the bottom-right to the top-left of the diagram. In a second step, we move to the larger COSMOS field where we have been able to detect 80 Lyman break galaxies (out of ~ 15,600) in the far infrared. They form the largest sample of Lyman break galaxies at z > 2.5 detected in the far-infrared. We tentatively name them Submillimeter Lyman break galaxies (S-LBGs).

ON THE NATURE OF SODIUM EXCESS OBJECTS

  • Jeong, Hyunjin;Yi, Sukyoung K.;Kyeong, Jaemann;Sarzi, Marc;Sung, Eon-Chang;Oh, Kyuseok
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.47.2-47.2
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    • 2014
  • Several studies have reported the presence of sodium excess objects having neutral atomic absorption lines at $5895{\AA}$ (NaD) and $8190{\AA}$ that are deeper than expected based on stellar population models that match the stellar continuum. The origin of these lines is therefore hotly debated. van Dokkum & Conroy proposed that low-mass stars (0.3M) are more prevalent in massive early-type galaxies, which may lead to a strong NaI 8190 line strength. It is necessary to test this prediction, however, against other prominent optical line indices such as NaD, Mgb, and Fe5270, which can be measured with a significantly higher signal-to-noise ratio than NaI 8190. We identified a new sample of roughly one thousand NaD excess objects (NEOs; ~8% of galaxies in the sample) based on NaD line strength in the redshift range 0.00$H{\beta}$ line strengths and significant emission lines, which are indicative of the presence of young stellar populations. This result implies that the presence of the interstellar medium and/or dust contributes to the increase in NaD line strengths observed for these galaxies.

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A Clonorchiasis Case of a Leopard Cat, Prionailurus bengalensis euptilurus, Diagnosed by Ultrasonography and Egg Detection in Republic of Korea

  • Choe, Seongjun;Jeong, Dong-Hyuk;Yang, Jeong-Jin;Kim, Jeongho;Na, Ki-Jeong;Lee, Dongmin;Park, Hansol;Jeon, Hyeong-Kyu;Eom, Keeseon S.
    • Parasites, Hosts and Diseases
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    • v.57 no.3
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    • pp.299-302
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    • 2019
  • A clonorchiasis case in a captive leopard cat, Prionailurus bengalensis euptilurus, was confirmed by ultrasonographic findings and egg morphologies found in the bile juice sample in the Korea. The leopard cat was introduced from the wild habitat of Gyeongsangnam-do, to Cheongju Zoo in Cheongju-si, Chungcheongbuk-do, Korea in August 2014. Physical examinations were basically performed for quarantine and check-up health. The cat was comparatively good in health except anorexia. The cyst-like bile duct dilation and the increased echogenicity of gall bladder wall and hepatic parenchyma were observed by ultrasonography. Ultrasound-guided needle biopsy was conducted for collecting bile juice and the specimens were observed under light microscope. The numerous small trematode eggs were detected in the bile juice sample of the light microscopy. The eggs were $25-33(28{\pm}3){\mu}m$ by $18-22(20{\pm}1){\mu}m$ in size and showed typical characteristics of Clonorchis sinensis egg, i.e., a dominantly developed operculum, shoulder rim and dust-like wrinkles in surface. To treat the liver fluke infection, 20 mg/kg of praziquantel was orally administered only once to the case. Follow-up studies including fecal examinations were conducted during 2 years after treatment. But no more eggs were detected from the case. In the present study, we described the first clonorchiasis case of leopard cat, which was confirmed by ultrasonographic findings and egg morphologies from the bile juice sample in Korea.

Characteristics of Regulated Heavy Metals Content in Wastes Emitted from Industrial Processes (산업공정폐기물 중 규제대상 중금속류의 함량 특성)

  • Jeon, Tae-Wan;Lee, Dong-Jin;Yoon, Jung-In;Oh, Gil-Jong;Hwang, Dong-Gun
    • Journal of Korean Society of Environmental Engineers
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    • v.31 no.6
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    • pp.449-453
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    • 2009
  • This study focused on the content characteristics of regulated hazardous substances in specific wastes. Regulated heavy metal such as Cu, Pb, Cd analyzed the 108 waste samples that it choice from the representative facilities. Analytical method used content test method, suggested on the basis of analytical method of developing country, and the results as compared with limited standard in Austria Petroleum, primary metalworking and electronic industry had high content of Cu more than 100 mg/kg of Austria limited standard. Pb detected high level concentration the sample that dust producted at Primary metalworking industry. In case of total Cr was show that high content at KSIC 18, 19, 23 etc but result analyzed Cr(VI), it was shown that high level at dust producted from sewing clothes and fur industry.

A Basic Study for Treating E.A.F. Dust by use of Waste Tire (폐타이어를 이용한 제강분진 처리를 위한 기초연구)

  • 황용길;이상화;이성룡;정석수;최재신;조충형
    • Resources Recycling
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    • v.4 no.4
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    • pp.59-69
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    • 1995
  • Distillation oI the dust generated during waste tue pyrolysis was perIomerl to rccover valuable metal sucll as zlnc. lead and iron. Pemcahilily and carnprcssivc tests were pursucd to ahlain the basic dala for cslraclian of zinc from the slntering propcrtp ol stccl making dusts and distilled carhon of waste tires as wcll as wastc pulp sludge mixlure hr~quet were investigated at various sinlcring lempcraturcs. Permeablllly rncieased with increastng amount of waste pulp in specil~cd istilled carhon due tn the fnrmat~ono f porusily in lhe sample TIE co~npress~vsctr ength showed the vanous values wlth different amDunl of dislilled-carhon adrlit~nilsa nd at diIIerenl sinlering tcmpcralures. X-ray diffifraction anvlyscs oI a hnquet rn~rhtre of steelmaking dusts(20Q didilled carhon and 10% waste pulp sblered ;>I SOOT) showcd thal the briquet consisted ot ZnO and Fc,O.,, hut was not found at the hriguet rintered at over 10OO'C. Crude zinc oxide sintered a1 IOOOC contained OZA Zn.

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Measurement of Radon Daughters in Airborne Dust (공기부유진내(空氣浮游塵內)의 Radon 붕괴생성물(崩壞生成物)의 농도측정(濃度測定))

  • Kim, Pill-Soo;Min, Duck-Kee;Ro, Seung-Gy
    • Journal of Radiation Protection and Research
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    • v.2 no.1
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    • pp.9-16
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    • 1977
  • A simple method has been established for determining RaA, RaB and RaC concentrations in airborne dust. This is to evaluate the concentration from measurement of total alpha activities in three selected-time intervals after an air sample is taken from the membrane filter paper (mean pore size: $0.8{\mu}m$). As a preliminary trial, a time-variation of the concentrations has been determined using the single-filter method at the KAERI site (N. Lat. $37^{\circ}38'$ and E. Long $127^{\circ}15'$), Seoul, Korea. It appears that there is a large variation of the concentrations depending on the sampling time. Generally the highest value was observed in the morning that may coincide with the highest density of atmosphere in a day while the lowest value was obtained around fourteen o'clock.

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Analysis of Korean Medical status of Acute Bronchitis, Chronic Bronchitis and Allergic Rhinitis patients (급·만성 기관지염과 알레르기성 비염의 국내 의료 이용 현황 분석)

  • Jung, You Jin;Yang, Woong Mo
    • The Journal of Korean Medicine
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    • v.40 no.3
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    • pp.87-98
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    • 2019
  • Objectives: Patients with respiratory diseases are increasing as air pollution due to fine dust gets worse. Diseases that occupy a large proportion of respiratory diseases in medical institutions are acute bronchitis, chronic bronchitis and Allergic rhinitis. The number of patients with all three diseases is gradually increasing. This study was to suggest assignment of medicine policy for improving accessibility to Korean medical treatment of respiratory diseases analyzing the current treatment status of acute bronchitis, Chronic bronchitis and Allergic rhinitis patients in Western medical and Korean medical institutes in this situation. Methods: This study used 2017 National patient sample data from the Korean Health Insurance Review and Assessment Service for research. Acute bronchitis, Chronic bronchitis, Allergic rhinitis was according to KCD code. This research contains Socio-demographic analysis classified by sex and age, the number of three disease's patients. Also the number of medical treatment, the expense of recuperation cost, medical practices were analyzed compare with Western and Korean medicine. Results: The incidence of three diseases is higher among female than male. There are many patients under the age of 10 in the case of acute bronchitis and allergic rhinitis, while there are many patients over 50 years of age in chronic bronchitis. Western medical treatment take up a larger proportion than Korean medical treatment in part of the number of three disease's patients, the number of medical treatment, the expense of recuperation cost. Conclusions: Much more patients of these diseases visit in Western medical clinic and hospital than Korean medical clinic and hospital for treatment. There are many parts of Korean medical treatment that are not covered by Health insurance benefits like herbal decoction, pharmacopuncture, etc. Korean medicine need to do the efforts for expanding medical field in variety. Also it is demanded for institutional support for reduction of the cost burden and improving on accessibility of Korean medical treatment in order to treat with the increase in respiratory diseases due to fine dust.

Testing delayed AGN feedback using star formation rate measurements by SED fitting with JCMT/SCUBA-2 data

  • Kim, Changseok;Jadhav, Yashashree;Woo, Jong-Hak;Chung, Aeree;Baek, Junhyun;Lee, Jeong Ae;Shin, Jaejin;Hwang, Ho Seong;Luo, Rongxin;Son, Donghoon;Kim, Hyungi;Woo, Hyuk
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.40.2-40.2
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    • 2021
  • The impact of AGN on star formation is one of the main questions in AGN-galaxy coevolution studies. However, direct evidence of AGN feedback is still rare. One of the main obstacles is that various star formation rate (SFR) indicators are contaminated by AGN contribution. We present IR-based SFR measurements of a sample of 52 local (z<0.3) AGNs, which were selected based on kinematical properties of ionized gas outflows, using SED analysis with JCMT/SCUBA-2 data. First, we will compare IR-based SFR with other SFR indicators to check the reliability of the SFR indicators. Second, we will discuss the contribution of Mid-IR emission from hot dust of AGN torus by comparing SED fitting results with and without including AGN dust component. Finally, we will report the correlation between specific SFR (sSFR) and AGN activity (e.g., outflow strength or Eddington ratio) as evidence of no instantaneous feedback and discuss the implications of these results

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OVERVIEW OF THE NORTH ECLIPTIC POLE DEEP MULTI-WAVELENGTH SURVEY (NEP-DEEP)

  • Matsuhara, H.;Wada, T.;Takagi, T.;Nakagawa, T.;Murata, K.;Churei, S.;Goto, T.;Oyabu, S.;Takeuchi, T.T.;Ohyama, Y.;Miyaji, T.;Krumpe, M.;Lee, H.M.;Im, M.;Serjeant, S.;Peason, C.P.;White, G.;Malkan, M.A.;Hanami, H.;Ishigaki, T.;Burgarella, D.;AKARI NEP Team, AKARI NEP Team
    • Publications of The Korean Astronomical Society
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    • v.27 no.4
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    • pp.123-128
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    • 2012
  • An overview of the North Ecliptic Pole (NEP) deep multi-wavelength survey covering from X-ray to radio wavelengths is presented. The main science objective of this multi-wavelength project is to unveil the star-formation and AGN activities obscured by dust in the violent epoch of the Universe (z=0.5-2), when the star formation and black-hole evolution activities were much stronger than the present. The NEP deep survey with AKARI/IRC consists of two survey projects: shallow wide (8.2 sq. deg, NEP-Wide) and the deep one (0.6 sq. deg, NEP-Deep). The NEP-Deep provides us with a $15{\mu}m$ or $18{\mu}m$ selected sample of several thousands of galaxies, the largest sample ever made at these wavelengths. A continuous filter coverage at mid-IR wavelengths (7, 9, 11, 15, 18, and $24{\mu}m$) is unique and vital to diagnose the contribution from starbursts and AGNs in the galaxies at the violent epoch. The recent updates of the ancillary data are also provided: optical/near-IR magnitudes (Subaru, CFHT), X-ray (Chandra), FUV/NUV (GALEX), radio (WSRT, GMRT), optical spectra (Keck/DEIMOS etc.), Subaru/FMOS, Herschel/SPIRE, and JCMT/SCUBA-2.