• 제목/요약/키워드: Green emission

검색결과 1,028건 처리시간 0.026초

Synthesis and Emission Properties of Ca1-1.5xMoO4:Tbx3+ Green Phosphors

  • 전용일;조신호;김문환
    • 한국표면공학회:학술대회논문집
    • /
    • 한국표면공학회 2012년도 춘계학술발표회 논문집
    • /
    • pp.196-196
    • /
    • 2012
  • 녹색 형광체 $Ca_{1-1.5x}MoO_4:Tb_x{^{3+}}$ 세라믹 형광체를 고상 반응법을 사용하여 $Tb^{3+}$ 이온의 농도를 변화시키면서 소결 온도 $1050^{\circ}C$와 환원 온도 $950^{\circ}C$에서 각각 5 시간과 2 시간 반응시켜 합성하였다. 형광체의 결정 구조, 여기 및 발광 특성의 변화를 각각 X-선 회절 장치와 광여기 발광 분광기를 사용하여 측정하였다. XRD 결과로부터, 합성된 모든 형광체 분말의 주 피크는 (112)면에서 회절된 신호임을 확인할 수 있었다. 형광 특성의 경우에 여기 스펙트럼은 303 nm를 중심으로 넓은 밴드를 형성하였고, $Tb^{3+}$ 이온의 농도가 증가함에 따라 550 nm에 주 피크를 갖는 녹색 형광 스펙트럼의 세기는 감소하였다.

  • PDF

Chemiluminescence Properties of Polymeric Fluorophores Containing Distyrylarylene Unit

  • 이희우;김철희;공명선
    • Bulletin of the Korean Chemical Society
    • /
    • 제22권7호
    • /
    • pp.727-731
    • /
    • 2001
  • Conjugated-non-conjugated alternating block copolymers containing distyrylarylene units were synthesized via Wittig reaction for chemiluminescent fluorophores. The polymers were differentiated from others by the presence of aromatic unit in the chromophoric block. When UV-VIS, photoluminescence and chemiluminescence spectra of these materials were compared with copolymers, a strong bathochromic effect was observed. A more pronounced red shift and higher chemiluminscence efficiency were observed in the polymer with anthracene ring. Sodium salicylate-catalyzed reaction of bis(2-carbopentyloxy-3,5,6-trichlorophenyl) oxalate with hydrogen peroxide produced a strong chemiluminescence from blue to yellow-green light emission with wavelength of 450-537 nm in the presence of the fluorophore. The chemiluminescent intensity decayed exponentially. The glow of chemiluminescence maintained more than l2 hr and was visible with the naked eye.

클린룸의 에너지 절약 기술 개발과 신뢰성 향상의 필요성에 관한 연구 (A Study on the Necessity for Energy Saving Techniques and Improvement of Dependability of Clean room)

  • 김종걸;김형만;김영섭;고재규;최성원;조국형
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 2008년도 추계학술대회
    • /
    • pp.641-647
    • /
    • 2008
  • Since korea must get 5.2% reduction of green gas emission and insecurity of economic impact is on the increase due to unstable oil market, the demands of energy saving techniques are increasing. In this paper, we investigate necessity of development of enormous energy used cleanroom energy saving techniques furthermore we also investigate the adoption of dependability management system to develop the energy saving cleanroom development process.

  • PDF

Post-2020 파리협정 대응 한국의 국제탄소시장 활용방안 (Korean Application Plans for International Carbon Markets by Coping with the Paris Agreement)

  • 노상환
    • 한국기후변화학회지
    • /
    • 제9권1호
    • /
    • pp.91-102
    • /
    • 2018
  • The Korean government submitted the Intended Nationally Determined Contributions (INDC) to UNFCCC which aims to reduce 37% greenhouse gas emission for the opportunity of developing new energy industry and industry innovation by 2030 compared with Business-As-Usual scenario taking into account its international responsibilities and hosting headquarters of Green Climate Fund (GCF) secretariat. The 37% reduction is composed of 25.7% in the domestic markets and 11.3% in the international carbon markets. To achieve the reduction target in the international carbon market mechanisms, it must use the linkage of international carbon markets and develop new renewable energy technology for CDM and ODA. Finally, it must improve carbon capture storage (CCS) technology and establish domestic CCS institutional systems as soon as possible. And, it must activate CCS information exchange for the international cooperation on UNFCCC movement.

정공수송층이 역구조 OLED의 전기 및 광학적 특성에 미치는 영향 (Effect of Hole Transport Layer on the Electrical and Optical Characteristics of Inverted Organic Light-Emitting Diodes)

  • 임세진;문대규
    • 한국전기전자재료학회논문지
    • /
    • 제36권4호
    • /
    • pp.397-402
    • /
    • 2023
  • We have developed inverted green phosphorescent organic light emitting diodes (OLEDs) using 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) and bis(carbazole-9-yl)biphenyl (CBP) hole transport layers. The driving voltage, current efficiency, power efficiency, and emission characteristics of devices were investigated. While the driving voltage for the same current density was about 1~2 V lower in the devices with the TAPC layer, the maximum luminance was higher in the device with the CBP layer. The maximum current efficiency and power efficiency were 3.2 and 2.7 times higher in the device with the CBP layer, respectively. The higher efficiency in the CBP device resulted from the enhanced hole-electron balance although weak parasitic recombination takes place in the CBP hole transport layer.

국제 공동 연구를 통한 태양에너지 활용 열화학 물분해 그린 수소 생산 연구 및 E-fuel 생산 연구 동향 보고 (Hydrogen and E-Fuel Production via Thermo-chemical Water Splitting Using Solar Energy)

  • 조현석
    • 신재생에너지
    • /
    • 제20권1호
    • /
    • pp.110-115
    • /
    • 2024
  • Global sustainable energy needs and carbon neutrality goals make hydrogen a key future energy source. South Korea and Japan lead with proactive hydrogen policies, including South Korea's Hydrogen Law and Japan's strategy updates aiming for a hydrogen-centric society by 2050. A notable advance is the solar thermal chemical water-splitting cycle for green hydrogen production, spotlighted by Korea Institute of Energy Research (KIER) and Niigata University's joint initiative. This method uses solar energy to split water into hydrogen and oxygen, offering a carbon-neutral hydrogen production route. The study focuses on international collaboration in solar energy for thermochemical water-splitting and E-fuel production, highlighting breakthroughs in catalyst and reactor design to enhance solar thermal technology's commercial viability for sustainable fuel production. Collaborations, like ARENA in Australia, target global carbon emission reduction and energy system sustainability, contributing to a cleaner, sustainable energy future.

환경 인쇄 기술의 발전과 인쇄물의 $CO_2$ 발생량에 관한 연구 (A Study about Development of Environment Printing Technology and $CO_2$)

  • 이문학
    • 한국인쇄학회지
    • /
    • 제30권3호
    • /
    • pp.89-114
    • /
    • 2012
  • For as to world, the concern about the environment problem is enhanced than any other time in the past because of being 21 century. And the environment problem is highlighted as the world-wide issue. The time of the environment problem intimidates the alive of the mankind and presence of an earth over the time. It becomes the essentiality not being selection in the personal living or the economical viewpoint now to prepare for the climatic modification. As to the company management, the green growth period which it excludes the environment management considering an environment, cannot carry on the company the continued management comes. That is, in the change center of the management paradigm, there is the environment management. Nearly, the greenhouse gas which the publication industry is the environmental toxic material like all industries is generated. The greenhouse gas is ejected in the process of running the manufacturing process and print shop of the various kinds material used as the raw material of the book. Particularly, the tree felling for getting the material of the paper is known to reach the direct influence on the global warming. This study does according to an object it considers and organizes the environment parameter based on this kind of fact as to the publication industry. And it is determined as the reference which is used as the basic materials preparing the case that carbon exhaust right transaction(CAP and TRADE) drawing are enforced in all industries and is sustainable the management of the publication industry and reduces the environmental risk among the company many risk management elements and plans and enforces the publication related policy that there is a value. In the printing publication industry, this study tried to inquire into elements discharging the environmental pollutant or the greenhouse gas. Additionally, in the printed publication production process, it tried to inquire into the effort for an environment-friendly and necessity at the printing paper and the printers ink, regarded as the element discharging the greenhouse gas all kinds of the printing materials, operation of the print shop and all kinds of the machines and recycle process, and etc. These considerations make these industrial field employees aware of the significance about a conservation and environmental protection. They try to give a help in the subsequent study producing quantitatively each environmental parameter emission of green house gas. This makes the calculation of the relative $CO_2$ output reproached ultimately possible. Meanwhile, in a sense, many research protects and improving an environment in connection with the contents of research at the printing publication industrial field is in progress. There will be the voluntary human face that it has to protect an environment but this can not do by the outside factor according to all kinds of environment related law and regulation. Anyway, because of acting on company management as the factor of oppression, the increase of this environment-related correspondence cost could know that the research that the environment loading relates with a procurement and development, environment management system introduction, quality control standard, including, normalizing including a material, and etc. through the part of the effort to reduce the cost low was actively in progress. As to the green growth era, as follows, this paper prescribed the subject and alternative of the print publication industry. It is surrounded by the firstly new digital environment and the generation of the subject. And secondly the printing industry is caused by the point of time when the green growth leaves by the topic which is largest in the global industry and it increases. The printing publication industry has to prepare the bridgehead for the environment-friendly green growth as the alternative for this resolution with first. The support blown in each industry becomes the obligation not being selection. Prestek in which the print publishing was exposed to spend many energies and which is known as the practice of the sustainable print publishing insisted that it mentioned importance of the green printing through the white pages in 2008 and a company had to be the green growth comprised through the environment-friendly activity. The core management for the sustainable printing publication industry presented from Presstack white pages is compacted to 4 words that it is a remove, reduce, recover, and recycle. Second, positively the digital printing(POD) system should be utilized. In the worldwide print out market, the digital printing area stops at the level of 10% or so but the change over and growth of the market of an analog-to-digital will increase rapidly in the future. As to the CEO Jeff Hayes of the Infoland, the offset print referred to that it of the traditional method got old and infirm with the minor phase of the new printing application like the customer to be wanted publication and the print of the digital method led the market. In conclusion, print publishers have to grasp well the market flow in the situation where a digitalization cannot be generalized and a support cannot avoid. And it keeps pace with the flow of the digital age and the recognition about the effort for the development and environment problem have to be raised. Particularly, the active green strategy is employed for the active green strategy.

한국의 GSP 공여를 통한 온실가스감축 개도국 지원방안에 관한 연구 - 인도네시아, 브라질, 에티오피아를 중심으로 - (A Study on the Impact of Korean GSP on Greenhouse Gas Emission Reduction of Developing Countries - Focusing on Indonesia, Brazil, and Ethiopia -)

  • 김민철;박성환;박중구
    • 에너지공학
    • /
    • 제20권1호
    • /
    • pp.63-76
    • /
    • 2011
  • 본 논문은 기후변화협약 당사국회의(COP)에서 지속적으로 갈등을 빚고 있는 개도국의 대선진국 기술개발 지원요구 등에 대응할 수 있는 방안 중 하나로서 일반특혜관세제도(Generalized System of Preferences : GSP)의 도입가능성을 연구하였다. 한국이 GSP의 공여국이 될 경우 온실가스 감축이 예상되는 무역분야를 인도네시아, 브라질, 에티오피아 등 3개국을 대상으로 분석하였다. GSP효과를 분석하는 방법론으로는 양국간 무역경쟁을 나타내는 산업내 무역지수에 한국의 수입유발계수를 가중치로 곱한 값을 사용하였다. 분석의 결과, 한-아세안 자유무역지역(FTA) 관세율을 우선 적용받는 인도네시아의 경우 무관세가 아닌 농림 수산 목축품목에 GSP 혜택을 부여했을 때 한국으로 수출이 증가할 것이며 동분야에서 온실가스 감축이 일어날 것으로 예상되었다. 브라질의 경우 한국이 수입특화하고 있는 제1차금속, 유지, 음식료 등에서 수입량이 증가하면서 온실가스 감축이 발생할 것으로 나타났다. 에티오피아는 '최빈개발도상국에 대한 특혜관세 공여 규정'에 해당하는 최빈국이지만 특례조항에 의해 배제된 농림수산물과 섬유, 가죽 품목에서 GSP 공여의 효과가 있는 것으로 나타났다. 다만, 본 논문은 수혜적인 성격이 강한 GSP 공여에 대해 현재 세계무역규범 상에서는 구속력을 부여하는 방안이 없다는 한계점을 가지고 있다.

$Zn_{2-x-y}SiO_4:Mn_x,\;M_y$계 형광체의 발광특성 (Photoluminescence Properties of $Zn_{2-x-y}SiO_4:Mn_x,\;M_y$ Phosphors)

  • 조봉현;손기선;박희동;장현주;황택성
    • 대한화학회지
    • /
    • 제43권2호
    • /
    • pp.206-212
    • /
    • 1999
  • 본 연구의 목적은 기존의 $Zn_2SiO_4:Mn$형광체에 새로운 co-dopant를 첨가하여 발광특성을 향상시키는 것이다. co-dopant로서 선정한 Mg와 Cr이온들은 Zn자리를 치환하는 것으로 알려져 있으며 실제로 co-doping 시 각각 발광휘도와 decay time을 개선시키는 효과를 거두었다. $Zn_2SiO_4:Mn$에 Mg와 Cr이온들이 co-doping될 시에는 lattice 및 $Mn^{2+}$의 에너지 준위를 변화시키는 것으로 추정되어 발광휘도 및 decay time의 변화를 일으키는 것으로 해석된다. 특히 이 원소들은 발광과정에 긍정정인 영향을 끼쳐 Mg는 발광휘도를 중가시키고 Cr은 decay time을 감소시키는 결과를 얻었다. $Zn_2SiO_4:Mn,\;Mg$ 형광체의 발광휘도 개선은 DV-X${\alpha}$ embedded cluster 계산방법으로 설명할 수 있었고 반면에 $Zn_2SiO_4:Mn,\;Cr$ 형광체가 decay time을 줄이는 원인은 Mn이온과 Cr이온사이에 energy transfer가 일어나 발생되는 것으로 추정된다.

  • PDF

졸-겔법에 의한 c-축 배향성을 가진 고투과율 ZnO 박막의 제조 (Sol-gel Derived-highly Transparent c-axis Oriented ZnO Thin Films)

  • 이영환;정주현;전영선;황규석
    • 한국안광학회지
    • /
    • 제13권1호
    • /
    • pp.71-76
    • /
    • 2008
  • 목적: 저온에서 열처리에 의해 소다-라임-실리카 유리 위에 강한 UV방사 나노결정 ZnO박막을 단순하고 효율적 방법으로 개선하고자 한다. 방법: 소다-라임-실리카 유리 위에 코팅되고 전열처리 및 300$^{\circ}C$의 후열처리를 행하여 제조된 나노 결정질 ZnO 박막의 결정 구조적, 표면 형상적 및 광학적 특성을 X-선 회절 분석, 전계방사 주사형 전자 현미경, 원자간력 현미경, ultra violet - visible - near infrared spectrophotometer 및 photoluminescence를 이용하여 분석하였다. 결과: 가시광 영역에서 높은 투과율과 자외부에서 뚜렷한 흡수밴드를 갖는 c-축으로 고배향된 ZnO 박막을 300$^{\circ}C$의 후열처리를 통하여 얻을 수 있었다. 비교적 뚜렷한 near band edge 발광을 보이는 photoluminescence 스펙트럼이 나타났으며, 결함에 의한 완만한 녹색 발광은 거의 관찰되지 않았다. 결론: 앞으로 본 연구는 300$^{\circ}C$ 이하의 저온에서 저렴하고 쉽게 ZnO을 기초로한 광전기 소자에 적용될 것이다.

  • PDF