• Title/Summary/Keyword: Green emission

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Change of Characteristic Curves using Light Emission Spectrum of the Intensifying Screens (증감지의 발광스펙트럼에 따른 특성곡선의 변화)

  • Yoon, Chul-Ho;Kang, Hong-Seok;Lee, In-Ja;Huh, Joon
    • Journal of radiological science and technology
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    • v.13 no.2
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    • pp.21-25
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    • 1990
  • This report is study about difference of H-D curve in regular film and ortho type film, and obtained results as follows : 1. In the blue-color emission intensifying screen, ortho type films and in the green-color emission intensifying screens, regular type are decreased in their gradient. 2. When joint use of regular type film and ortho type film, the gradient difference not seen in blue color screen. 3. The gradient difference seen clearly in G4, KM screens(green color emission intensifying). Especially, in part of high film density, the gradient difference are great. So we have to right use of screen and film because not matched used of theare the sensitivity and gradient are decrease.

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Synthesis of Barium Hexaaluminate Phosphros Using Combinatorial Chemistry (조합화학을 이용한 망간(2+)과 유로피움)2+)이 첨가된 Barium Hexaaluminate 형광체의 합성 및 광특성 분석)

  • 박응석;최윤영;손기선;김창해;박희동
    • Journal of the Korean Ceramic Society
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    • v.37 no.2
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    • pp.134-139
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    • 2000
  • The main objective of the present investigation is to show the feasibility of combinatorial chemistry by applying this method to phosphor syntehses. In this respect barium hexaaluminate phosphor was prepared by the split-pool combinatorial method, which enabled much more rapid search of optimum compositions of target phosphors than conventional synthetic methods. Barium hexaaluminate phosphors doped with Eu2+ exhibit blue emission while those co-doped with Mn2+ and Eu2+ exhibit green emission. Basically, the phosphor doped with 1.3 mole of Ba and 0.06~0.15 mole of Eu2+ exhibit the maximum value of emission intensity at 435${\mu}{\textrm}{m}$. Under the UV and VUV extitations, the barium hexaaluminate phosphor co-doped with Mn2+ and Eu2+ shows strong green emission.

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Tandem white organic light emitting diodes comprising of red, green, blue emission

  • Yang, Jung-Jin;Suman, C.K.;Lee, Chang-Hee
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.820-822
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    • 2009
  • Tandem white organic light emitting diodes (WOLEDs) are fabricated by using a transparent interconnecting layer of Al:LiF composite/molybdenum oxides ($MoO_3$). We demonstrate two types of tandem WOLEDs consisting of two color emissions (red and blue emission) and three color emissions (red, green and blue emission). Tandem WOLED consisting of three color emission shows higher external quantum efficiency and current efficiency.

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Exhaust Gas Recirculation System Applied to 56 kW Off-Road Vehicle to Satisfy the Tier 4 Interim Emission Regulation (Tier 4 Interim 배기규제 만족을 위한 56kW급 오프로드 차량 EGR 적용에 관한 연구)

  • Kang, Jeong-Ho;Han, Joon-Sup;Chung, Jae-Woo;Jeong, Gun-Woo;Cho, Gyu-Baek;Lim, Jung-Ho;Pyo, Su-Kang
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.2
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    • pp.217-224
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    • 2012
  • In general, transportation sources include both on-road vehicles and off-road equipment. Off-road vehicles have usually used diesel engines, which have the disadvantage of high NOx emission. Common rail direct injection (CRDI) and after-treatment systems have been applied to meet the exhaust gas emission regulations for diesel vehicles. In the present, agricultural machinery has satisfied the Tier 3 emission regulations by using waste gate turbocharger (WGT) and internal exhaust gas recirculation (EGR). In this paper, the combustion and emission characteristics of an EGR system applied to a 56kW off-road vehicle in non-road transient cycle (NRTC) mode have been investigated. The EGR map was made from foundation experiments determining the EGR duty for all engine operating conditions, and then this map was applied to the NRTC mode. Consequently, the NOx emission was reduced by the EGR system, and the Tier 4 interim emission regulations were satisfied by using both the EGR system and an after-treatment system.

VUV luminescence properties of a novel green-emitting $(Y,Gd)Ga_3(BO_3)_4$:Tb phosphor

  • Moon, Young-Min;Choi, Sung-Ho;Lim, Sang-Ho;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1561-1564
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    • 2007
  • $Tb^{3+}-activated$ green-emitting $(Y,Gd)Ga_3(BO_3)_4$ phosphor has been investigated. The main absorption was in the $120{\sim}238$ nm and exhibited a green emission with the 545 nm and several peaks due to inner shell transition of $Tb^{3+}$ ion. With the optimized $Tb^{3+}$ concentrations, the maximum emission brightness was 90% of the $Zn_2SiO_4$:Mn phosphor.

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Preparation and Luminescence Properties of PDP Green Phosphors using Polymer Matrix Technique

  • Jun, Sang-Bae;Lee, Dong-Kyu;Kim, Soo-Jong;Masaki, Takaki;Han, Chung-Hwa
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.3
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    • pp.121-124
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    • 2007
  • The $Zn_2SiO_4:Mn$ phosphors were prepared using polymer matrix technique in order to improve the performance of green emitting phosphors for plasma display panel(PDP). $Zn_2SiO_4:Mn$ phosphor exhibits a strong green emission around 520-530 nm. The emission intensity and particle size of powders were controlled by sintering temperature and raw material composition. The zinc silicate $Zn_2SiO_4:Mn$ single phase were obtained at lower temperature than prepared by solid-state reaction method. PL luminance of $Zn_2SiO_4:Mn$ phosphor was similar to the commercial material.

The Study on the Improved Quantum Efficiency of the PVK:Bu-PBD:C6 Single Layer Green Light Emitting Devices (PVK:Bu-PBD:C6 단일층 녹색발광소자의 양자효율 개선에 관한 연구)

  • 조재영;노병규;오환술
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.14 no.11
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    • pp.922-927
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    • 2001
  • Single-layer green ELs was fabricated with using molecularly-dispersed Bu-PBD into poly-N-vinylcarbazole(PVK) which has low operating voltage and high quantum efficiency. A EL cell structure of glass substrate/indium-tin-oxide/PVK:Bu-PBD:C6(∼ 100nm)/Ca(20nm)/Al(20nm) was employed with variable doping concentration. The keys to obtain high quantum efficiency was excellent film forming capability of molecularly dispersed into PVK and appropriate combination of cathode for avoiding exciplex. We obtained the turn-on voltage of 4.2V and quantum efficiency of 0.52% at 0.lmol% of C6 concentration which has been improved about a factor of 50 in comparison with the undoped cell. The PL peak wavelengths wouldn\`t be turned by changing the concentration of the C6 dopant. Green EL emission peak and FWHM were 520nm and 70nm respectively. PL emission peak was obtained at 495nm.

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Reduction of Green House Gases by Bioenergy Supplying in Korea (국내 바이오에너지 보급에 따른 온실가스 저감 평가)

  • Hong, Yeon Ki
    • Journal of Institute of Convergence Technology
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    • v.4 no.1
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    • pp.15-20
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    • 2014
  • Recently, the development of renewable energy sources in Korea has been needed due to climate change. One of powerful alternative energy resources to mitigate emission is to switch conventional fuels to renewable energy, such as bioenergy. In this study, current status of bioenergy conversion technology and its supply in Korea was investigate. Based on theoretical, technical and realizable potential of biomass in Korea, the amount of reduction of green house gases was estimated. The results shown that the contribution of biomass on 2020 reduction target of green house gases emission in power generation was $513,000\;tCO_2/yr$ and utilization ratio of technical potential of biomass was 6.4%. For the effective supply of bioenergy in Korea, more exact estimation of realizable potential of biomass in Korea and stable supply sources are needed.

Visible light emission from $C_60$ and Si nanoparticle film by laser process (C60 및 Si 초미립자 박막의 Laser 반응에 의한 가시광선발광)

  • ;Hideomi Koinuma
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.11a
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    • pp.598-601
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    • 2000
  • We investigated the fabrication of Si nanoparticle and $C_{60}$ thin films by pulsed laser ablation. As a result, we observed visible green photoluminescence spectra in the Si/C$_{60}$ multilayer films after laser annealing. It is considered that this green photoluminescence is occurred from SiC particles, which is produced reaction of Si nanoparticles with $C_{60}$ via laser annealing.ing.

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Searching for the environmental management plans of Korea paper industry coping with the new climate regime (신 기후체제 협약에 따른 국내 제지산업의 환경경영 방안 모색)

  • Kim, Dong Seop;Sung, Yong Joo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.2
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    • pp.75-82
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    • 2016
  • The new climate regime for practical reduction in green house gas(GHG) emissions was launched in Paris at Dec. 2015. The Korea government would make various policies and plans in order to achieve the BAU 37 % emission reduction goals by 2030. In this study, the current situation and the possible corresponding methodology to the GHG emission reduction of Korea paper industry were investigated. Although the GHG emission reduction in KOREA paper industry has been successfully conducted compared with other industries until now, the more efforts for controlling GHG emission would be required to meet the new climate regime. The efficiency of various GHG reduction projects conducted by Korea paper companies was evaluated to find efficient way for GHG reduction. The certified methodologies of the external project based offset systems in Korea GHG emission trading scheme were also reviewed for providing the possible way to develope tailored methodology to the Korea paper industry.