• 제목/요약/키워드: Red/F-Red

검색결과 821건 처리시간 0.032초

Investigation of a New Red-Emitting, Eu3+-Activated MgAl2O4 Phosphor

  • Singh, Vijay;Haque, Masuqul;Kim, Dong-Kuk
    • Bulletin of the Korean Chemical Society
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    • 제28권12호
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    • pp.2477-2480
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    • 2007
  • MgAl2O4:Eu3+ red-light emitting powder phosphor was prepared at temperature as low as 500 oC within a few minutes by using the combustion route. The prepared powder was characterized by X-ray diffraction, scanning electron microscopy and Fourier-transform infrared spectrometry. The luminescence of Eu3+-activated MgAl2O4 shows a strong red emission dominant peak around 611 nm, which can be attributed to the 5D0-7F2 transition of Eu3+ ions from the synthesized phosphor particles under excitation (394 nm). Electron paramagnetic resonance (EPR) measurements at the X-band showed that no signal could be attributed to Eu2+ ions in MgAl2O4.

Luminescence of $Eu^{3+}-doped\;GdCa_4B_3O_{10}$ phosphor under UV and VUV irradiation

  • Oh, Jae-Suk;Kwak, Chung-Heop;Jung, Ha-Kyun
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.1355-1359
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    • 2006
  • Due to its efficient red emission, $Eu^{3+}$ ion has been doped in various host materials. $GdCa_4B_3O_{10}:Eu^{3+}$ phosphor for red emission has been prepared by solid state reaction. Photoluminescence properties for the phosphor under UV and VUV excitation were investigated. The $GdCa_4B_3O_{10}:Eu^{3+}$ phosphor under both excitation conditions shows typical red emission spectrum centered at 611 nm with several weak peaks due to energy transfer from $^5D_O\;to\;^7F_J(J=1,2,3,4)$ of $Eu^{3+}$ ion. On the other hand, the activator content exhibiting the concentration quenching under UV and VUV irradiation is 10 mole% and 2.5 mole%, respectively.

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New Red Phosphor with the Improved Color Purity for PDP Applications

  • Mho, Sun-Il
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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    • pp.257-259
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    • 2002
  • As a new host material for a red phosphor for PDP applications, has studied (Y,Gd)$Al_3(BO_3)_4$ which gives non-centrosymmetric sites for $Eu^{3+}$ activators. Vacuum ultraviolet (VUV) excitation spectrum of new red phosphor (Y,Gd)$Al_3(BO_3)_4$:$Eu^{3+}$ has two broad bands. One band with the absorption edge at ca. 168 nm is the band-gap absorption of aluminoborate and the other broad band centered 240 nm is the charge transfer transition between $Eu^{3+}$ and the neighboring oxygen anions. The PL spectrum shows the strongest emission at 617 nm due to the electric dipole $^5D_0{\rightarrow}^7F_2$ transition of $Eu^{3+}$, whose luminescent chromaticity is (0.67, 0.33).

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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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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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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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연X선 및 요드반응에 의한 수삼의 품질평가 (Quality Evaluation of Fresh ginseng by Soft X-ray and iodine Test.)

  • 박훈;조병구;이미경
    • Journal of Ginseng Research
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    • 제8권2호
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    • pp.167-171
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    • 1984
  • Soft X-ray is useful to identify the quality of fresh ginseng causing the inside cavity or white pan of red ginseng. The portion of low mass density identified by the difference in absorption of soft X-ray showed lower dry matter density and less or no response to iodine test indicating less accumulation or excess consumption of starch. The inside white part of red ginseng absorbed less X-ray than the normal part did. Probability for identification of the inside cavity or white at fresh ginseng was rather high (80-90%) in screen observation than f'3m reading and seemed to be increased further by using the developed screen and with training. The inside white of red ginseng appeared to be due to starch deficiency. Dry matter density appeared to be better than fresh weight density for the quality criterion.

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Luminescence Enhancement by Ba in SrTiO3:Pr, Al Red Phosphor for Field Emission Displays

  • Won, Chang-Whan;Lee, Jong-Eun;Won, Hyung-Il;Kim, Kwang-Bok;Song, Yoon-Ho;Kang, Seung-Youl;Koo, Kyoung-Wan
    • 한국세라믹학회지
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    • 제43권11호
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    • pp.743-745
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    • 2006
  • The luminescence properties of $Sr_{1-x}Ba_xTiO_3:Pr$, Al red phosphor for Field Emission Displays (FEDs) have been investigated in powders prepared though solid-state reactions. $Sr_{1-x}Ba_xTiO_3:Pr$, Al red phosphors indicate a higher luminescent intensity, and have been found to have potential for field emission displays. The addition of Ba increased the luminescence intensity at 617 nm by up to 30%. Ba ions are effective in producing the energy transfers from host-to-activator in 4f-5d transitions.

적조발생시기 참돔의 절식과 사육밀도에 따른 성장과 혈액성상 (Growth and Blood Characteristics of Red Sea Bream Pagrus major by Starvation and Stocking Density during Red Tide)

  • 김원진;이정용;신윤경;원경미
    • 한국어류학회지
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    • 제30권4호
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    • pp.194-204
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    • 2018
  • 본 연구는 매년 C. polykrikoides 적조에 의해 발생하는 양식 어류 폐사의 피해를 최소화하기 위해 적조시기 참돔의 절식과 밀도의 영향을 조사하였다. 해상가두리($11m{\times}11m{\times}5m$)에서 섭식-고밀도(F-HD), 절식-고밀도(S-HD), 절식-저밀도(S-LD) 세 그룹으로 구분하여 5주간의 절식 후 4주간의 먹이공급을 통해 참돔의 생존율, 성장, 성장회복 그리고 혈액학적 변화를 조사한 결과, 생존율은 F-HD에서 85.5%로 가장 낮았고, S-LD는 97.3%로 높은 생존율을 보였다. 5주간의 절식기간 동안 두절식구는 전장, 체중 성장률에서 마이너스 성장을 보여 섭식구와 유의한 차이를 보였다(P<0.05). 하지만 먹이 재공급 후두 절식구 모두 성장회복을 보였다. 특히 S-LD는 먹이 재공급 기간 동안 빠른 성장회복을 통해 보상성장 경향을 보였으며, 섭식구와 유의한 차이를 나타냈다(P<0.05). ALB, TCHO, TP, TG 혈액분석을 통한 실험구의 영양상태는 절식구에서 섭식구에 비해 유의하게 감소하였지만 먹이 공급 후 실험개시 시 수준으로 빠르게 회복하였다. 스트레스와 생리활성 지표인 Ht, Hb, AST, ALT 그리고 GLU가 적조 노출 후 F-HD에서 동일한 시기에 급격히 상승하여, 적조시기 섭식, 고밀도 사육환경은 양식어류에게 더 민감한 사육환경으로 작용할 것으로 여겨진다. 따라서 본 연구의 적조시기 절식과 밀도에 따른 생존율, 성장회복, 혈액성상을 통한 결과를 토대로, 적조 노출에 따른 절식과 밀도 조절이 사육어류 관리방안을 위한 기초자료로 활용될 수 있을 것이다.

홍파프리카로 담근 깍두기의 이화학적.관능적 특성 (Physicochemical and Sensory Characteristics of Kakdugi Prepared with Red Paprika Powder)

  • 이지숙;이영주;김미리
    • 동아시아식생활학회지
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    • 제13권1호
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    • pp.64-71
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    • 2003
  • Physicochemical and sensory characteristics of Kakdugi substituted red pepper powder with red paprika powder during fermentation at 1$0^{\circ}C$ were compared with those of the control. The fermentation patterns of two Kimchies were similar. While the pH and the acidity of the control were 3.88 and 0.691%(as lactic acid), respectively, those of paprika, 3.85 and 0.690%(as lactic acid), respectively on the 10th day of fermentation, which is the optimal ripe time. Reducing sugar content and Lactobacilli number of paprika Kakdugi were higher than those of the control. The hardness and fracturability of Kakdugi radish were not significantly different from those of the control during fermentation. The Hunter color L, a and b values of both Kakdugies increased gradually until l0th day and then decreased. The a and ASTA value of paprika Kakdugi was higher than that of control, which is consistent with the results of sensory evaluation. Capsaicin and dihydrocapsaicin analyzed by HPLC were not detected in paprika Kakdugi. Sensory evaluation (unstructured scale, 10 points) showed the score of hot taste f3r paprika Kakdugi was lower than that of the control(p<0.05), whereas the score of over-all acceptabillity for paprika Kakdugi(8.0) was higher than those of control(6.1).

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색채기호도와 성격특성 및 개인적 요인과의 관계 연구 (The Relationship between Color Preference and Personality Traits & Personal Factor)

  • 백숙희;최종명;김인숙
    • 한국생활과학회지
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    • 제3권1호
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    • pp.71-80
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    • 1994
  • The purpose of this study was to investigate the relationship between color preference and personality traits & personal factor among secondary school girls. Personality traits were measured. with Lee et al's Personality Scale. The questioniare measuring color preference consists of items designed to assess color and clothing color(T-shirt and slacks) preference and color repugnance. These questionaire were administerd to 576 middle and high school girls in Chungbuk Province. As statistical analysis, chi-square, F-test and correlation were used. The result were; 1. The order of prefered colors were white, yellow and green, and the order of repugnated colors were gray, red and red purple. 2. Personality traits was no signifcant related to color perference and repugnance. 3. Color perference was positively related to age, residential area and type of school. Color repugnance was positively related to age, residential area, type of school and educational background of mother. 4. Yellow red, yellow and white T-shirt were prefered in spring and autumn, white and blue T-shirt were prefered in summer, and black, gray and red T-shirt were prefered in winter. White and blue slacks were prefered in spring, summer and autumn seasons, and black, gray and blue slacks were prefered in winter. 5. There was a positive relationship between color perference and T-shirt color, but was no positive relationship between color perference and slacks color.

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Rubrene과 DCM2가 첨가된 적색 유기전계발광소자의 발광특성 (Luminescent characteristics of OLED doped with DCM2 and rubrene)

  • 박용규;성현호;김인회;조황신;양해석
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.939-942
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    • 2001
  • We fabricated Red Organic light-emitting devices(OLED). The Basic Device Structure is ITO/hole transfer layer, TPD(50nm)/red emitting layer, Alq3 doped with DCM2 or DCM2:rubrene(xnm)/electorn transfer layer, Alq3(50-xnm)/LiF(0.8nm)/Al(8nm) . The thickness of emitting layer(xnm) changed 5, 10, 20nm. we demonstrate red emitting OLED with dependent on the thickness and concentrators of Alq3 layer doped with DCM2 or co-doped with DCM2:ruberene. The Emission color and Brightness are changed with doping or co-doping condition, dopant concentarton. In the case of rubrene:DCM2 co-doped layer structure, the red color Purity and device efficiency is improved. The CIE index of rubrene co-doped OLED is x=0.67, y=0.31. By co-doping the Alq3 layer with DCM2, rubrene, EL efficiency improved from 0.38cd/A to 0.44cd/A in comparison whit DCM2 doped Alq3 layer.

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