• Title/Summary/Keyword: 탄소입자

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Energy Loss of Hydrogen Atom due to Charge Exchange in Neutral Particle Energy Analyzer (중성입자 에너지 분석장치에서 전하교환용 탄소박막에 의한 수소원자의 에너지 손실특성)

  • Kim, Kye-Ryung;Kim, Wan;Lee, Yong-Hyun;Kang, Hee-Dong
    • Journal of Sensor Science and Technology
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    • v.7 no.3
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    • pp.179-187
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    • 1998
  • A neutral particle energy analyzer, which has the carbon stripping foil and the $90^{\circ}$ cylindrical electrostatic deflection plate, was designed and constructed for measuring of ion temperature in plasma. The energy calibration and energy resolution were studied in detail for a hydrogen ion at the $0.5{\sim}3.0\;keV$ energy using a duoplasmatron ion source. An energy of hydrogen ion to the deflection plate voltage at the peak ion count rate could be fitted by the expression $E_{o}(keV)$=3.83V(kV). The measured energy resolution, which was about 2 % at the energy of 3.0 keV and 9 % at the energy of 0.5keV, was better for the increased hydrogen ion energy. For the charge exchanged hydrogen atom due to the carbon stripping foil, the energy calibration, energy loss and resolution were measured to the $0.5{\sim}2.0{\mu}g/cm^{2}$ thickness of the carbon stripping foil. An energy of the charge exchanged hydrogen atom as a function of the deflection plate voltage and carbon foil thickness could be fitted by the expression $E_{o}(keV)=(0.53d+4.4){\cdot}V(kV)$. The energy loss was $0.23{\sim}0.89\;keV $ to the $0.5{\sim}2.0{\mu}g/cm^{2}$ carbon foil thickness and the $0.5{\sim}3.0\;keV$ energy of the incident neutral hydrogen atom, it could be fitted by the expression ${\Delta}E=(0.12d+0.27){\cdot}{E_{o}}^{1/2}(keV)$. The measured energy resolution for the neutral hydrogen atom, which was between 7 % and 35 % in this experiment region, was increased for the increasing neutral hydrogen atom energy and the decreasing carbon stripping foil thickness.

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Preparation of Core/Shell Nanoparticles Using Poly(3,4-ethylenedioxythiophene) and Multi-Walled Carbon Nanotube Nanocomposites via an Atom Transfer Radical Polymerization (Poly(3,4-ethylenedioxythiophene)을 이용한 Core/shell 나노입자와 원자이동 라디칼중합 공정에 의한 다중벽 탄소나노튜브 나노복합체 제조)

  • Joo, Young-Tae;Jin, Seon-Mi;Kim, Yang-Soo
    • Polymer(Korea)
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    • v.33 no.5
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    • pp.452-457
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    • 2009
  • Hybrid nanomaterials consisting of multi-walled carbon nanotube(MWNT) and/or PEDOT of conductive polymer were prepared in this study. In the presence of catalyst and ligand, the MWNT-Br compound prepared by the successive surface treatment reaction was mixed with MMA to initiate the atom transfer radical polymerization process. PMMA was covalently linked to the surface of MWNT for the formation of MWNT/PMMA nanocomposites. The EDOT and oxidant were added in the aqueous emulsion of PS produced via a miniemulsion polymerization process and then it proceeded to carry out the oxidative chemical polymerization of EDOT for the preparation of PEDOT/PS nanoparticles with the core-shell structure. The aqueous dispersion of PEDOT:poly(styrene sulfonate) (PSS) was mixed with the silica particles treated with a silane compound and thus PEDOT:PSS-clad silica nanoparticles were prepared by the surface chemistry reaction. The hybrid nanomaterials were analyzed by using TEM, FE-SEM, TGA, EDX, UV, and FT-IR.

Sediment Trap Studies to Understand the Oceanic Carbon Cycling: Significance of Resuspended Sediments (퇴적물 트랩을 이용한 해양 탄소 순환 연구 동향: 재부유 퇴적물의 중요성)

  • KIM, MINKYOUNG
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.26 no.2
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    • pp.145-166
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    • 2021
  • For several decades, sediment traps have served as one of the key tools for constraining the biological carbon pump (BCP), a process that vertically exports particulate organic carbon (POC) and associated biogenic materials from marine primary production in surface waters to the deep ocean interior. In this paper, I introduced the general methods, the current status of global sediment trap studies, and importance of it to understand the deep ocean carbon cycling. Recent studies suggest that sinking POC in the deep ocean are more complex and spatio-temporally heterogeneous than we considered. Especially researches those studied resuspended and laterally transported particles are presented. Researches that used organic (radiocarbon; 14C) and inorganic (Al) tracers to understand the oceanic POC cycling and the significance of resuspended particles are reviewed, and the importance of radiocarbon study by using MICADAS (Mini radioCarbon Dating Systems) is emphasized.

Removal of Unburned Carbon from Fly Ash using Countercurrent Column Flotation Cell (역류형 컬럼 부선기를 이용한 석탄회정제에 관한 연구)

  • 이전언;이제군
    • Resources Recycling
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    • v.8 no.5
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    • pp.51-58
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    • 1999
  • The sbdy iwestlgaled ihc propa-ties of Lhe dust\ulcorner rrom fe~~oallomya ~~ufacturTeh. e chemical composition, cornpasitlon material, p d c l e sire md shapes of the bulk dust, sired dust and magnetically separated durl were mvesligaled. As the re\ulcornerulL, we suppose that the dust from &gh Carbon Fenama~~gunesMc anuiact~vingP rocess is not sufiicient as solulce material of Mn because of ale low Mn canlenl (13.5%) and complicaled composition mate~ial. The dust from Bug F!lter or AOD Proccss is mi~inlym ade up of 0.2-2 pm Mn30, (Hausmam~iu)p iutlde in spherical shape and thc Mn content is 63.190.The dust from Cooler of AOD Process is inninly made up of coarse Ca(O1-Or)zM. n,FeyO,, SiO, and fine Mn30d.

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Synthesis of Porous Carbon Particles for the Absorption of Mercury (액상수은 제어를 위한 다공성 탄소입자 제조에 관한 연구)

  • Lee, Jung-Min;Kang, Shin-Jae;Park, Soo-Jin
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.305-305
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    • 2009
  • The carbon nano-structured materials could be applied to the fields of advanced fillers, templates, electrode materials, sensor, storage, and absorption materials. The polyacrylonitrile (PAN) based carbon nano-particles provide the remarkable properties of high specific surface area, large pore volume, chemical inertness, and good mechanical stability. In this study, well-defined carbon nano-particles were obtained through pyrolysis of polyacrylonitrile based particles. The precursor nano-particles were prepared by modified aqueous dispersion polymerization using hydrophilic poly(vinyl alcohol) in a water/ N,N-dimethylformamide mixture media. Synthesized precursor nanoparticles have relatively monodisperse particles ranging 80 ~ 250nm. Stable spherical particles are obtained without coagulum or secondary particles in our system. The characteristic of the carbon nanoparticles were investigated in terms of surface area, morphology, and size distribution.

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