• 제목/요약/키워드: Blue-Green

검색결과 1,560건 처리시간 0.032초

Green Light-Emitting Phosphor, Ba2xCaMgSi2O8:Eux

  • Kim, Jeong-Seog;Piao, Ji-Zhe;Choi, Jin-Ho;Cheon, Chae-Il;Park, Joo-Suk
    • 한국세라믹학회지
    • /
    • 제42권3호
    • /
    • pp.145-149
    • /
    • 2005
  • [ $Eu^{2+}$ ]-activated barium magnesium silicate phosphor, $(Ba,Ca)_{3}MgSi_{2}O_{8}:Eu_{x}$, has been known to emit blue-green light. In this study we report the manufacturing processes for producing either pure green or pure blue light-emitting phosphor from the same composition of $Ba_{2-x}Ca_{2}CaMgSi_{2}O_{8}:Eu_{x}$ (0 < x < 1) by controlling heat treatment conditions. Green light emitting phosphor of $Ba_{1.9}CaMgSi_{2}O_{8}:Eu_{0.1}$ can be produced under the sample preparation condition of highly reducing atmosphere of $23\%\;H_2/77\%\;N_2$, while blue or blue-green light emitting phosphor under reducing atmosphere of $5\~20\%\;H_2\;/\;95\~80\%$ N_2. The green light-emitting phosphors are prepared in two steps: firing at $800\~1000^{\circ}C$ for $2\~5$ h in air then at $1100\~1350^{\circ}C$ for 2-5 h under reducing atmo­sphere $23\%$ $H_2/77\%\;N_2$. The excitation spectrum of the green light-emitting phosphor shows a broadband of $300\~410$ nm. The emission spectrum has a maximum intensity at the wavelength of about 501 nm. The CIE value of green light emission is (0.162, 0.528). The pure blue light-emitting phosphors can be produced using the $Ba{2_x}CaMgSi_{2}O_{8}:Eu_{x}$ by introducing additional firing step at $1150\~1300^{\circ}C$ in air before the final reducing treatment. The XRD analysis shows that the green light-emitting phosphor mainly consisted of $Ba_{1.31}Ca_{0.69}SiO_{4}$ (JCPDS $\#$ 36-1449) and other minor phases i.e., $MgSiO_3$ (JCPDS $\#$ 22-0714) and $Ca_{2}BaMgSi_{2}O_{8}$ (JCPDS $\#$ 31-0128). The blue light-emitting phosphor mainly consisted of $Ca_{2}BaMgSi_{2}O_{8}$ phase.

식별제(Unimark 1494DB) 정량시험에서 파란색 색소(Orimax Blue 2N, Orimax Green 151), Quinizarin, 토파졸(P-250) 및 윤활유 원료(P-8)의 흡광도상승 효과 (Absorbance Elevation of Orimax Blue 2N, Orimax Green 151, Quinizarin, Topasol (P-250) and Lubricant (P-8) on the Spectrophotometric Analysis of Unimark 1494 DB)

  • 이지윤;김창종
    • 약학회지
    • /
    • 제50권5호
    • /
    • pp.313-321
    • /
    • 2006
  • There are three kinds of liquid petroleum marker which is extracted by the basic or acidic, and both developer. Korean marker, Unimark 1494 DB (marker) have been spectrophotometrically analysed by the determination of absorbance at 582 nm after base extraction by Unimark 1494 DB Developer C-5 (developer). Some blue dyes which have same reactive radical of marker and can be changed deep blue color in base developer extraction (BDE), may be increased absorbance at 582 nm, but dyes or markers which can be increased the absorbance, were not unclear. In this experiment, effects of three dyes or marker such as Orimax Green 151 (the mixture of CI Solvent Yellow 16 and CI Solvent Blue 70), quinizarin and Orimax Blue 2N (CI Solvent Blue 35), and two solvent such as topasol (P-250) and lubricant (P-8) on the absorbance were studied by HITACHI Recording Spectrophotometer U-3300. It shows that all of them increased absorbance at 582 nm after BDE. Absorbance at 582 nm can be showed 0.0544 by Orimax Green 151 at the concentration of 3.96 mg/l, quinizarin at the concentration of 1.38 mg/l, and Orimax Blue 2N at the concentration of 2.73 mg/l in the artificial petroleum (normal diesel oil: topasol: lubricant=2 : 4: 4), respectively. Absorbance, 0.0544 indicates that concentration of marker is 1.64 mg/l in the reference curves, respectively. And also these results can be showed that the artificial petroleum have about 10% cheep fuel such as kerosene which have marker (16.0 mg/l). Absorbance of P-250 was 0.01361-0.22842 depending upon the purchasing date, and that of P-8 was 0.05644. pH of developer was 14.83, and so this result indicates that Unimark 1494 DB is a base extractable petroleum marker, phenylazophenol (US Patent No. 5,252,106). In the BDE, the slight color of Orimax Blue 2N, Orimax Green 151 and quinizarin in artificial petroleum changed to deep bright blue color, respectively. These result indicate that the absorbance at 582 nm by BDE may be increased not only by azo, diazo, amine and ketone (anthraquinone, coumarin) dyes or markers, but also the contaminants of P-250 and P-8 which have same as reactive radical of dyes or markers.

대청호의 식물플랑크톤 군집 변화 (Community Dynamics of Phytoplankton in Lake Daecheong)

  • 박종근;이정준
    • ALGAE
    • /
    • 제20권3호
    • /
    • pp.197-205
    • /
    • 2005
  • Temporal variability in lake phytoplankton is controlled by a complex between hydrological and chemical factors, and biological interactions. We explored annual change of phytoplankton in Lake Daecheong, using phytoplankton analysis data from 1997 to 2002 (except 2000). The standing crop of phytoplankton was ranged from 3.5 x 10 to 1.5 x 106 cells mL$^{-1}$ and the highest mean value was at site 1. The class composition ratios of phytoplankton standing crop were divided into three classes. From January to March, diatoms showed a dominance (68.1-77.7%). From April to June, diatoms were mixed with cryptomonad etc. or blue-green algae. From July to October, blue-green algae showed a dominance (54.7-84.0%). In the case of green algae, the class composition ratios were below 10%. But green algae appeared all the year round.

A New Galaxy Classification Scheme in the WISE Color-Luminosity Diagram

  • Lee, Gwang-Ho;Sohn, Jubee;Lee, Myung Gyoon
    • 천문학회보
    • /
    • 제38권2호
    • /
    • pp.49.1-49.1
    • /
    • 2013
  • We present a new galaxy classification scheme in the Wide-field Infrared Survey Explorer (WISE) [$3.4{\mu}m$]-[$12{\mu}m$] color versus $12{\mu}m$ luminosity diagram. In this diagram, galaxies can be classified into three groups in different evolutionary stages. Late-type galaxies are distributed linearly along "MIR star-forming sequence" identified by Hwang et al. (2012). Some early-type galaxies show another sequence at [3.4]-[12] $(AB){\simeq}-2.0$, and we call this 'MIR blue sequence'. They are quiescent systems with old stellar population older than 10 Gyr. Between the MIR star-forming sequence and the MIR blue sequence, some early- and late-type galaxies are sparsely distributed, and we call these galaxies 'MIR green cloud galaxies'. Interestingly, both MIR blue sequence galaxies and MIR green cloud ones lie on the red sequence in the optical color-magnitude diagram. However, MIR green cloud galaxies have lower stellar masses and younger stellar populations (smaller $D_n4000$) than MIR blue sequence galaxies, suggesting that MIR green cloud galaxies are in the transition stage from MIR star-forming sequence galaxies to MIR blue sequence ones. We present differences in various galaxy properties between the three MIR classes using a multi-wavelength data, combined with the WISE and Sloan Digital Sky Survey Data Release 10, of local (0.03 < z < 0.07) galaxies.

  • PDF

백색 UV-LED를 위한 $Eu^{2+}$-활성화 칼슘 알루미늄 실리케이트 형광체 연구 (The Study of $Eu^{2+}$-activated Calcium Aluminium Silicate Phosphors for White UV-LED)

  • 황정하;장보윤;박주석
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
    • /
    • pp.32-35
    • /
    • 2006
  • For the white UV-LED applications, $Eu^{2+}$-activated calcium aluminium silicate phosphors were synthesized for the first time and the structures and luminescence characteristics of these phosphors were investigated. The phosphors in this study emitted blue. green or blue-green light depending on the starting materials for synthesis. In addition, the structure was also changed when the different starting materials were used. When CaO and $CaCO_3$ was used as a starting material. tetragonal $Ca_2Al_2SiO_7$ was formed and blue-green and pure green light was emitted. respectively. However. in the case of $CaSiO_3$, triclinic $CaAl_2Si2O_8$ was formed and only pure blue emission was detected. The maximum emission intensity was obtained from $CaAl_2Si_2O_8:Eu^{2+}$ phosphors, which intensity was about 1.4 times higher than that of YAG:$Ce^{3+}$ phosphor used for blue LED.

  • PDF

잔디 엽병을 유발하는 잠재인자로서의 남조류(Blue-Green algae)에 대한 관찰보고 (Blue-green algae as a Potential agent Causing Turf Leaf Disease)

  • 박대섭;이형석;홍범석;최병만;전재찬
    • 아시안잔디학회지
    • /
    • 제22권2호
    • /
    • pp.161-170
    • /
    • 2008
  • 본 연구는 아직 국내에서 보고된 바 없는 조류에 의한 잔디 병 발생 가능성에 대한 연구로, 2008년 7월 경기지역 골프장내 켄터키 블루그래스가 식재된 티잉그라운드에서 흑갈색 얼룩 반점병을 일으킨 잎조직이 발견되면서 조류에 의한 잔디 병 발생 요인과 대책을 조사하였다. 1. 켄터키 블루그래스의 흑갈색 반점 염조직으로부터 다수의 남조류(blue-green algae)가 관찰되었고, 흑갈색 반점이 형성 부위의 엽몸, 엽귀, 그리고 엽집에서 남조류가 다수 발견되었으며, 이병조직 이외의 개체내 건전부위와 줄기에서도 남조류 파편이 발견되었다. 발견된 남조류는 Oscillatoria 계통이 많았다. 2. 잔디밭에서 남조류는 토양 내 뿌리나 지제부에서 관찰되는데, 이번 관찰시에는 켄터키 블루그래스의 흑갈색 얼룩반점 병반부위인 상단 엽조직에서 남조류가 관찰되었다. 또한 이병조직 주위의 건전한 부위에서도 작은 파편형태의 남조류들이 발견되었다. 이것은 현재까지 식물조직 내 남조류의 이동경로에 대하여 알려진 바가 없지만 조직 내에서 남조류의 이동 가능성도 있다. 3. 흑갈색 얼룩반점이 형성된 켄터키 블루그래스 뿐만 아니라 황화현상이 발생한 벤트그래스 퍼팅그린의 잔디 잎에서도 남조류가 관찰되었으므로, 향후 초종에 따른 조류의 영향에 대한 세부연구가 수행되어져 야 할 것이다. 4. 약제처리로 조류 억제와 흑갈색 얼룩 반점 경감효과를 가져왔는데 프로피코나졸이 가장 우수하였고 이프로디온과 아족시스트로 빈 순으로 조류 억제가 관찰되었다. 6. 특히 고온 다습한 여름철에 조류 방제가 어렵고 적절한 조류억제제를 선택하기가 쉽지 않다. 이에 따라, 조류에 대한 일반적 관리에 머무르기보다는 더 적극적인 방제 방안 및 사전 예방 관리를 강구하여야 할 것이다. 6. 끝으로 향후 조류의 잔디 조직 내 이동 및 감염 경로를 규명하고자 하는 지속적인 연구가 진행되어야 할 것이다.

중국인의 색지각 특성에 관한 연구 -한국, 중국과 일본 3국인의 색지각 특성비교를 중심으로- (A Study on the Characteristics of the Color Perception of Chinese People : Focused on a Comparison of the Characteristics of Color Perception among Korean, Chinese and Japanese People)

  • 조영미;성지은;안옥희
    • 조명전기설비학회논문지
    • /
    • 제27권5호
    • /
    • pp.1-8
    • /
    • 2013
  • The purpose of this study is investigate the characteristics of color perception among Chinese people, and compare the characteristics among Korean, Chinese and Japanese people, using Munsell color space. The results are as follows: 1) Chinese people were more likely to tell accurately red, yellow red, yellow, purple, and an achromatic color, but did not do accurately green yellow, blue, and purple blue. In terms of a comparison of average perceived color and standard color, there were significant differences among green yellow, blue green, and blue and standard color; 2) Color perceptions of Korean, Chinese and Japanese people were broadly classified into four types. Also, of ten chromatic colors, the color perception type of only two colors, red and yellow, were is same among the groups of the three countries. However, the color perception type of yellow red, green, blue green and blue were different among them; and 3) In terms of a color perception accuracy test among the groups of the three countries, there were not significant differences between yellow and purple and standard color. However, significant differences existed between the rest of the colors and standard color.

국내 녹색-청색계열 무기안료의 산출과 광물학적 특성 (Occurrence and Mineralogical Properties of Green-Blue Inorganic Pigments in Korea)

  • 정기영;조현구;도진영
    • 한국광물학회지
    • /
    • 제31권1호
    • /
    • pp.33-46
    • /
    • 2018
  • 단청, 불화, 벽화 등에 사용된 전통 무기질 안료는 대부분 광물이었으나, 근현대에 저렴한 화학안료로 대체되어 광물안료 제조법의 맥이 끊어졌다. 이 연구에서는 문화재 보존에 필요한 전통 광물안료 중 녹색-청색 계열 안료자원의 국내 산출과 광물학적 특성을 규명하고자 하였다. 구리를 함유한 녹색 - 청색 안료광물들은 구리-납-아연을 채굴하는 금속광산의 폐석장이나 갱내 풍화대에서 이차광물로 산출되었다. X선회절과 주사전자현미경 분석을 이용하여 광물동정을 실시한 결과, 녹색은 brochantite, devilline, 청색은 linarite, bechererite, schulenbergite 등의 함수구리황산염이 대표적인 발색광물이었으며, 그 외 소량의 녹색 antlerite, atacamite가 확인되었다. 이들 녹색-청색 안료광물과 함께 cerussite, smithsonite, anglesite, cuprite 등이 이차광물로 흔히 수반되었다. 녹색 규산염 안료인 뇌록은 현무암 파쇄대의 교대산물로 산출되며, 주발색광물인 celadonite 외에 단백석이 다양한 비율로 혼재되어 있었다. 녹색 규산염 안료인 해록석은 사질 서해 퇴적물 내에서 산출이 확인되었다. 이번 조사에서 대표적인 구리계열 녹색-청색 전통안료로 알려진 공작석과 남동석의 산출을 확인할 수 없었다.

Exciplex emission in bilayer Light-emitting device

  • Liang, Yu-Jun;Zhang, Hong-Jie;Han, Sang-Do;Jung, Young-Ho;Taxak, Vinod Bala
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2002년도 International Meeting on Information Display
    • /
    • pp.762-765
    • /
    • 2002
  • The bilayer organic light-emitting diode using Al (DBM) $_3$ (DBM=Dibenzoylmethane) as an emitting material and poly (N-vinylcarbazole) (PVK) as hole-transport material, emitted bright blue-green light instead of blue light. The blue-green emission is attributed to exciplex formation at the solid interface between Al (DBM) $_3$ and the hole-transport material. The exciplex formation was evidenced by the measurement of the photoluminescence spectra and lifetimes of Al (DBM) $_3$, PVK and an equimolar amount of mixture of Al (DBM) $_3$ and PVK.

  • PDF

천연염료에 의한 염색(III) -배합 염색- (Dyeing with Natural Dye (III) - Combination Dyeing-)

  • Nam, Sung Woo;Lee, Sang Rag;Kim, In Hoi
    • 한국염색가공학회지
    • /
    • 제8권4호
    • /
    • pp.52-58
    • /
    • 1996
  • Until now, in case of natural dyeing, the appearance of medium colors were achieved by repeat dyeing with different colorants after dyeing with one colorant. In this study, however, new dyeing method for appearance of medium colors was developed by use of mixing solution of different colorants prepared with the same ratio using colorant concentrates. In combination dyeing, purple color was difficult to represent because of the Gardenia blue dye among the colorants used in this study was naby blue dye. But the other medium colors such as yellow red, green yellow, green and blue green were easily represented by use of reddish Sappan wood and yellowish Gardenia concentrates. If the natural blue dye is prepared in concentrate condition, the dyeings dyed in various colors may be obtained by combination dyeing.

  • PDF