• Journal of Information Display
• /
• 제8권1호
• /
• pp.10-13
• /
• 2007

We synthesized new blue and bluish green emitting materials by using fully substituted ethylene moieties. Multi-layered EL devices were fabricated with synthesized materials and evaluated in terms of emission color and luminescence efficiency. TBBPE[EML 2] device showed bluish-green CIE value of (0.236, 0.412) and 5.02cd/A at $10mA/cm^2$. BPBBPE[EML 3] device also showed sky-blue CIE value of(0.218, 0.355) and 2.31cd/A at $l0mA/cm^2$.

• 한국연소학회지
• /
• 제6권1호
• /
• pp.29-35
• /
• 2001

The surface flames in porous ceramic burner are experimentally characterized to investigate the effects of equivalence ratio and firing rates. The results show that the surface flames are classified into green, red radiant and blue surface flame as decrease of equivalence ratio. And each flame is maintained very stably and shows the same flame characteristics at any orientation of ceramic burner. Particularly the blue surface flame was found to be very stable at very lean equivalence ratio at 200 to $800\;kw/m^2$ firing rates. And the exhausted NOx was analysed to find out which flame has lower NOx emission. The blue surface flame showed the lowest NOx emission regardless of the location of burner since it sustained very stable at lean mixture ratio.

• 수산해양기술연구
• /
• 제47권4호
• /
• pp.327-337
• /
• 2011

This study was conducted to develop energy-efficient LED lamps with an excellent fishing performance for an anchovy scoop net by comparing the functions of 6 different lamps- incandescent, blue LED, green LED, white LED, yellow LED and red LED lamp. We used incandescent and red LED lamps only for the initial test and then excluded because those showed the lowest herding capacity. According to the result, yellow LED showed lower herding capacity in comparison with the blue, green and white one. Although the herding performance of the blue, green and white LED was similar in almost tests, herding speed to the each light was different. The anchovies were gathered into the blue LED as the speed of 39.88cm/s that was the fastest. Green LED was the second as the speed of 33.28cm/s. White LED was the slowest as the speed of 26.73cm/s. We will have field tests because we found the result that yellow LED's herding performance was better than green LED's for 5 seconds comparing after starting in some tests.

• Animal Bioscience
• /
• 제36권5호
• /
• pp.731-739
• /
• 2023

Objective: This study was to evaluate the interaction of three different light-emitting diode (LED) light colors (white, green, and blue) and three intensities (5, 10, and 15 lx) on slaughter performance, meat quality and serum antioxidant capacity of broilers raised in three-layer cages. Methods: A total of 648 (8-days-old) male broiler chicks (Cobb-500) were randomly assigned in 3×3 factorially arranged treatments: three light colors (specifically, white, blue, and green) and three light intensities (namely, 5, 10, and 15 lx) for 35 days. Each treatment consisted of 6 replicates of 12 chicks. The test lasted for 35 days. Results: The semi-eviscerated weight percentage (SEWP) in 5 lx white was higher than that in 15 lx (p<0.01). The eviscerated weight percentage (EWP) (p<0.05) and water-loss percentage (WLP) (p<0.01) decreased in 10 lx white light than those in green light. Under blue light, the content of hypoxanthine (Hx) in muscle was lower than that under white and green light (p<0.01). The content of malondialdehyde (MDA) in 15 lx blue light was higher than that in 10 lx green light (p<0.05). Light color had an extremely significant effect on thigh muscle percentage, WLP, Hx, and crude protein content (p<0.01). Light intensity had a significant effect on SEWP (p<0.05), EWP (p<0.05), lightness (L^*) value (p<0.05), WLP (p<0.01), and the contents of superoxide dismutase (p<0.05), MDA (p<0.01), glutathione peroxidase (p<0.01). Conclusion: Using white LED light with 10 lx light intensity can significantly improve the chicken quality of caged Cobb broilers, improve the content of inosine acid in chicken breast and enhance the antioxidant capacity of the body. We suggest that the broiler farm can use 10 lx white LED light source for lighting in 8 to 42 days.

• 보존과학회지
• /
• 제36권5호
• /
• pp.351-367
• /
• 2020

신구법천문도 3점(국립민속박물관 소장 『천문도(병)』, 『신구법천문도 8폭 병풍』, 일본 국회도서관 소장 『황도남북양총성도』)에 대한 채색 안료 분석 및 이를 통한 제작시기를 추정하였다. 『천문도(병)』에서는 조선에서 널리 사용되어오던 석청(남동광), 청화(쪽), 석록(공작석), 하엽(아타카마이트), 주, 석간주(산화철), 연지(코치닐), 등황, 석자황, 연분, 활석 등과 같은 전통적인 유·무기질 안료들이 사용되었다. 『신구법천문도 8폭 병풍』와 『황도남북양총성도』에서는 19세기 중엽 이후 유럽에서 유입된 합성 무기안료인 양록(에메랄드 그린)과 양청(울트라마린 블루)가 사용되었다. 『신구법천문도 8폭 병풍』에서는 녹색과 청색에 합성 무기안료만 사용되었지만, 『황도남북양총성도』에서는 전통적으로 사용되어온 하엽과 청화도 함께 사용되었다. 신구법천문도의 성도와 도설 연구와 연계하여 안료 분석결과로부터 추정한 제작시기는, 조선시대 전통안료만으로 채색된 『천문도(병)』 18세기 중엽 이후로 추정되며, 『황도남북양총성도』와 『신구법천문도 8폭 병풍』은 19세기 중엽 서양의 녹색과 청색 안료가 도입된 후 제작되었다. 그리고 전통안료와 서양의 합성안료가 함께 사용된 『황도남북양총성도』가 『신구법천문도 8폭 병풍』 보다 제작시기가 빠른 것으로 추정된다.

• 자연과학논문집
• /
• 제6권1호
• /
• pp.5-39
• /
• 1993

한국 해산 남조류(Cyanophyta) 의 목록을 작성하고 분류학적 위치를 확인하기 위하여 우리나라 전해역에서 채집된 남조류를 대상으로 형태분류학적 연구를 시도하였다. 그 결과 동정된 한국 해산 남조류는 총 3목 6과 20속 36종이며, 이 중 14종이 우리나라에서 그 생육이 처음으로 확인된 미기록종 (Chroococcus minutus ($K\"{u}$tzing) $N\"{a}$geli, Merismopedia punctata Meyen, Microcystis ichtyoblabe $K\"u$zing, Dermocarpa leibleiniae (Reinsch) Born. et Thur., Hydrocoleum confluens (Setchell et Gardner) Drouet, Lyngbya sordida (Zanard.) Gomont, Phormidium forveolarum (Mont.) Gomont, Phormidium hansgieri Schmidle, Skujaella hildebrandtii (Gomont.) de Toni, Sphaeronema lithophila (Ercegovic) Umezaki, Spirulina tenerrima $K\"u$tzing, Hormothamnion enteromorphoides Grunow, Michrochaete aeruginea Batters, Michrochaete grisea Thuret ex Born. et flah.)이었다. 본 연구에서는 간섭현미경과 위상차현미경을 이용하여 체형이 미소한 남조류의 현미사진을 작성하였다. 형태학적으로 분류된 각 종을 대상으로 세포내 함유물을 관찰하여 그 중 PHB ($poly-\SS$-hydroxybutyrate) granule의 존재 유무를 조사하였으며, Lyngbya confervoides, Lyngbya semiplena, Phormidium corium, Sirocoleum kurzii, Hormothanmnion enteromorphoides, Calothrix crustacea들은 PHB를 함유하고 있음이 확인되었다. 이 결과는 생리생화학적 특성을 기초로한 남조류의 분류체계를 정립하기 위한 자료로 활용될 수 있을 것이다.

• 현장농수산연구지
• /
• 제23권1호
• /
• pp.59-66
• /
• 2021

태양광에서 작물의 생육에 필요한 파장대역은 통과시키고, 필요하지 않은 파장대역은 발전에 이용할 수 있는 염료감응전지 개발을 위한 기초연구로 선택적 광투과에 따른 온실 환경 및 생육을 조사한 결과를 요약하면 다음과 같다. 조도 기준 투과율은 Blue필터 및 Green필터가 Red필터에 비하여 10%이상 높은 것으로 조사되었으나, 광량자속밀도 기준 투과율은 Red 필터 및 Blue필터가 Green필터에 비하여 10%이상 높은 것으로 조사되었다. 또한 적외선 30% 차단 필터 부착 온실은 다른필터 부착온실보다 온도가 낮을 것으로 예측하였으나, 큰 차이가 발생하지 않은 것으로 조사되어 창을 열어 제어하는 온실에서 열차단 필터의 적용은 적절하지 않을 것으로 판단되었다. 선택적 광투과 모형온실에서 재배한 파프리카의 생육을 조사한 결과 Green과 Blue필터 온실에서 파프리카의 도장정도가 가장 심하고 줄기가 연약하게 자라는 특성이 나타났지만, 적외선차단 필터 온실에서 파프리카 식물체의 생체중이 678.9g으로 가장 높았으며, Red필터와 대조구 온실은 상대적으로 그 생육이 저조한 것으로 조사되었다. 광합성 속도, 증산률, 기공전도도 모두 적외선차단필터 시험구와 대조구에서 높고 나머지 시험구에서 낮은 결과를 보였다. 반면에 수분이용효율은 시험구간에서 큰 차이를 보이지 않았다.

• 한국재료학회지
• /
• 제32권11호
• /
• pp.449-457
• /
• 2022

Halide perovskites are emerging materials for next-generation display applications, thanks to their narrow emission linewidth and band gap tunability, capable of covering the entire range of visible light. Despite their short period of research, perovskite light emitting diodes (PeLEDs) have shown rapid progress in device external quantum efficiency (EQE) in the near-infrared (NIR), red, and green emission wavelengths, and the record EQE has exceeded over 20 %. However there has been limited progress with blue emission compared to the red and green counterparts. In this review, the current status and challenges of blue PeLEDs are introduced, and strategies to produce spectrally stable blue PeLEDs are discussed. The strategies include 1) a mixed halide system in the form of 3-dimensional (3D) perovskites, 2) colloidal perovskite nanocrystals and 3) low dimensional perovskites, known as quasi-2D perovskites. In the mixed halide system, previous reports based on the compositional engineering of 3D perovskites to reduce spectral instability (i.e., halide segregation) will be discussed. Since spectral instability issue originate from the mixed halide composition in perovskites, the two other strategies are based on enlarging the band gap with a single halide composition. Finally, the prospects for each strategy are discussed, for further improvement in spectrally stable blue PeLEDs.

• 대한방사선기술학회지:방사선기술과학
• /
• 제11권1호
• /
• pp.3-16
• /
• 1988

Author has made an experiment on absolute speeds of 18 screenfilm combinations that have been on sale in Korea, with various beam qualities. At this time, the beam qualities were 60kVp with the ANSI extremity phantom, 80kVp with the ANSI chest phantom and 85kVp with 20 mm aluminium filter under scatter free condition. The obtained results were as follows; 1. When three independent measurements were performed, the percent standard deviations of mAs quantities of 1.0 + fog were decreased by the hardening of the beam quality, and the decreasing tendency was somewhat great in the blue systems. 2. Generally, the increasing tendency of absolute speeds was distinct by the hardening of the beam quality in the green systems. Conclusively, the green systems were more strongly dependent upon the beam quality rather than the blue systems. Therefore, the relative speed of green systems to blue systems were great under the same condition. 3. Differences in the green systems were kept almost constant even though the beam qualities were changed. 4. They were shown the mutual relationship of absolute speed and relative speed rather than independent.

• Transactions on Electrical and Electronic Materials
• /
• 제15권2호
• /
• pp.66-68
• /
• 2014

Most commercial white LED lamps use blue chip coated with yellow emitting phosphor. The use of blue excitable red and green phosphors is expected to improve the CRI. Several phosphors, such as $SrGa_2S_4:Eu^{2+}$ and $(Sr,Ba)SiO_4:Eu^{2+}$, have been suggested in the past as green components. However, there are issues of the sensitivity and stability of such phosphors. Here, we describe gallium substituted $YAG:Ce^{3+}$ phosphor, as a green emitter. YAG structures are already accepted by the industry, for their stability and efficiency. LEDs with improved CRI could be fabricated by choosing $Y_3Al_4GaO_{12}:Ce^{3+}$ (green and yellow), and $SrS:Eu^{2+}$ (red) phosphors, along with blue chip. Also, the effect of a slight change in chip wavelength is studied, for two phosphor-coated w-LEDs. The reduction in particle size of the coated phosphors also gives improved w-LED characteristics.