• Title/Summary/Keyword: trapping center

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Effect of Sunlight Polarization on the Absorption Efficiency of V-shaped Organic Solar Cells

  • Kang, Kyungnam;Kim, Jungho
    • Journal of the Optical Society of Korea
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    • 제18권1호
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    • pp.9-14
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    • 2014
  • We numerically investigate the effect of sunlight polarization on the absorption efficiency of V-shaped organic solar cells (VOSCs) using the finite element method (FEM). The spectral distribution of absorbance and the spatial distribution of power dissipation are calculated as a function of the folding angle for s-and p-polarized light. The absorption enhancement caused by the light-trapping effect was more pronounced for s-polarized light at folding angles smaller than $20^{\circ}$, where s-polarized light has a relatively larger reflectance than p-polarized light. On the other hand, the absorption efficiency for p-polarized light is relatively larger for folding angles larger than $20^{\circ}$, where the smaller reflectance at the interface of the VOSC is more important in obtaining high absorption efficiency.

선충 종류별 4종 포식성곰팡이의 포식력 차이 (Nematode-Trapping Fungi Showed Different Predacity among Nematode Species)

  • 강헌일;최인수;박남숙;배창환;김동근
    • 식물병연구
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    • 제25권3호
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    • pp.149-155
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    • 2019
  • 선충 포식성곰팡이는 유기물에서 번식하다가 양분이 부족해지면 특수 기관을 형성하여 선충을 포획하고 선충으로부터 양분을 섭취하기 때문에 토양 내 동물계와 먹이사슬을 이루며 생태계에서 중요한 부분을 차지한다. 본 연구에서는 끈끈이그물형 포식기관을 가진 3종, Arthrobotrys oligospora, A. sinensis, A. thaumasia과 수축성올가미형 포식기관을 가진 Drechslerella brochopaga 1종 등 4종의 선충 포식성곰팡이의 식세균성선충 9종, 식균성선충 1종, 식물기생성선충 2종 등 총 12종의 선충류에 대한 포식력을 검정하였다. 4종의 포식성곰팡이에 모두 감수성인 선충은 식물기생성선충 2종류(Meloidogyne incognita, Pratylenchus penetrans), Rhabditidae에 속하는 P. strongyloides, Mesorhabditis irregularis이었고 접종 4일 후부터 선충을 포식하였으며, 선충 내부로 곰팡이가 번식하여 15일째에는 거의 선충의 형태를 알아볼 수 없을 정도였다. 반면, Cephlobidae에 속하는 Acrobeloides spp., A. avenae는 4종의 포식성곰팡이에 모두 저항성을 보였으며 15일 후 관찰하였을 때, 접종배지 내에 선충 수가 초기접종 밀도와 같거나 오히려 2-3배 정도까지 번식되었다. 나머지 선충 종들은 포식성곰팡이 종류에 따라 감수성에 다소간 차이가 있었다. 본 연구결과, 선충 포식성곰팡이가 선충 종에 따라 특이적으로 반응하였으며 이러한 기주특이성을 이용하여 식물기생성선충의 친환경적 방제를 위한 하나의 수단으로 이용될 수 있다.

Sulfur에 의하여 치환된 ZnTe 단결정 박막의 광발광 특성 (Photoluminescence characteristics of ZnTe single crystal thin films substi-tuted by sulfur)

  • 최용대
    • 한국결정성장학회지
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    • 제13권6호
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    • pp.279-283
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    • 2003
  • 본 연구에서는 ZnTe에 S 원자를 소량 첨가한 ZnTe : S 단결정 박막이 열적적층법에 의하여 GaAs(100) 기판 위에 성장되었다. S 원자에 의한 효과를 알기 위하여 ZnTe : S 단결정 박막의 광발광 특성을 조사하였다. 저온 광발광 스펙트럼에서 등전자적 중심(isoelectronic center)으로 보이는 2.339 eV의 피크가 관측되었고, ZnTe 단결정 박막의 광발광 스펙트럼에서 근원을 알 수 없었던 발광 스펙트럼은 관측되지 않았다. 온도에 따른 가벼운 양공 자유 엑시톤의 세기 변화는 외부자기포획(extrinsic self-trapping)으로 설명하였다. 그리고 상온에서 에너지 띠간격 흡수단 근처의 발광선이 관측되었다.

Phenol Free Heat-Set 윤전 잉크의 인쇄적성에 관한 연구(제2보) - 실 인쇄 실험에 의한 분석 - (The Study of the Printability on the Phenol Free Heat-Set Web Inks(II) - Analysis by the trial printing test -)

  • 하영백;오성상;이원재
    • 펄프종이기술
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    • 제44권3호
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    • pp.41-48
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    • 2012
  • Materials used for the inks in the printing industry is an important material following the paper. The composition of the ink is pigment and organic solvents. However, Ink is used in a variety of chemicals, they are classified as non-green. Therefore, rosin-modified phenolics manufactured by the reaction of phenol and formaldehyde can take the place of eco-phenol free resin and by experiment density, gloss, trapping, contrast and dot gain of printing has been studied as printability. The result of study can support that the properties of printing using eco-phenol free resin such as density, gloss, contrast and trapping is similar to existing ink. In the part of dot gain, the result is excellent. So we were thought to be able to improve some characteristics such as dispersion of black ink, that will be possible for the field applicability.

Assessment of Treatment Response in Patients With Severe Asthma Using Visual and Quantitative Analysis of Chest CT

  • Han Na Lee;Jin An;Miji Lee;Hye Jeon Hwang;Jooae Choe;Jihye Yoon;Ji-Hyang Lee;Min-Hye Kim;Young-Joo Cho;Sang Min Lee;Tae-Bum Kim;Joon Beom Seo
    • Korean Journal of Radiology
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    • 제25권7호
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    • pp.673-683
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    • 2024
  • Objective: To evaluate the role of visual and quantitative chest CT parameters in assessing treatment response in patients with severe asthma. Materials and Methods: Korean participants enrolled in a prospective multicenter study, named the Precision Medicine Intervention in Severe Asthma study, from May 2020 to August 2021, underwent baseline and follow-up chest CT scans (inspiration/expiration) 10-12 months apart, before and after biologic treatment. Two radiologists scored bronchiectasis severity and mucus plugging extent. Quantitative parameters were obtained from each CT scan as follows: normal lung area (normal), air trapping without emphysema (AT without emph), air trapping with emphysema (AT with emph), and airway (total branch count, Pi10). Clinical parameters, including pulmonary function tests (forced expiratory volume in 1 s [FEV1] and FEV1/forced vital capacity [FVC]), sputum and blood eosinophil count, were assessed at initial and follow-up stages. Changes in CT parameters were correlated with changes in clinical parameters using Pearson or Spearman correlation. Results: Thirty-four participants (female:male, 20:14; median age, 50.5 years) diagnosed with severe asthma from three centers were included. Changes in the bronchiectasis and mucus plugging extent scores were negatively correlated with changes in FEV1 and FEV1/FVC (ρ = from -0.544 to -0.368, all P < 0.05). Changes in quantitative CT parameters were correlated with changes in FEV1 (normal, r = 0.373 [P = 0.030], AT without emph, r = -0.351 [P = 0.042]), FEV1/FVC (normal, r = 0.390 [P = 0.022], AT without emph, r = -0.370 [P = 0.031]). Changes in total branch count were positively correlated with changes in FEV1 (r = 0.349 [P = 0.043]). There was no correlation between changes in Pi10 and the clinical parameters (P > 0.05). Conclusion: Visual and quantitative CT parameters of normal, AT without emph, and total branch count may be effective for evaluating treatment response in patients with severe asthma.

Molecular Analysis of Rice Plants Harboring an Ac/Ds Transposable Element-Mediated Gene Trapping System

  • Hang Gyeong;Mi Sook Choe;Sung-Ho Lee;Sung Han Park;Hyuk Kim;Ja Choon Koo;No Youl Kim;Su Hyun Park;Jeung Joo Lee
    • 한국식물학회:학술대회논문집
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    • 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
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    • pp.17-20
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    • 1999
  • In rice, limited efforts have been made to identify genes by the use of insertional mutagens, especially heterologous transposons such as the maize Ac/Ds. We constructed Ac and gene trap Ds vectors and introduced them into the rice genome by Agrobacterium-mediated transformation. In this report, rice plants that contained single and simple insertions of T-DNA were analyzed in order to evaluate the gene-tagging efficiency. The 3'end of Ds was examined for putative splicing donor sites. As observed in maize, three splice donor sites were identified at the 3'end of the Ds in rice. Nearly 80% of Ds elements wered excised from the original T-DNA sites, when Ac cDNA was expressed under a CaMV 35S promoter. Repetitive ratoon culturing was performed to induce new transpositions of Ds in new plants derived from cuttings. About 30% of the plants carried at least one Ds that underwent secondary transposition in the later cultures. 8% of transposed Ds elements expressed GUS in various tissues of rice panicles. With cloned DNA adjacent to Ds, the genomic complexities of the insertion sites were examined by Southern hybridization. Half of the Ds insertion sites showed simple hybriodization patterns which could be easily utilized to locate the Ds. Our data demonstrate that the Ac/Ds mediated gene trap system could prove an excellent tool for the analysis of functions of genes in rice. We discuss genetic strategies that could be employed in a largee scale mutagenesis using a heterologous Ac/Ds family in rice.

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SrCl2:Eu2+,Na+ X-선 영상저장 형광체의 발광특성 (Luminescence in SrCl2:Eu2+,Na+ X-ray Storage Phosphor)

  • 김성환;김완;강희동;도시홍;서효진;김영국;김도성
    • 한국재료학회지
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    • 제13권6호
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    • pp.343-346
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    • 2003
  • Photoluminescence(PL), photostimulated luminescence(PSL) and thermoluminescence(TL) in $SrC1_2$:$Eu^{2+}$ , $Na^{+}$ phosphor powder were measured, and the activation energies(trap depth) of traps associated with TL and PSL were investigated. The PL and PSL in the studied sample is due to the $4f^{6}$ 5d\longrightarrow$4f^{7}$transition of $Eu^{ 2+}$. TL glow curve is single peak, and its peak temperature is about 377.2 K. The PL, PSL and TL emission spectra of the phosphors are located in the range of 380∼440 nm, peaking at 408 nm. The activation energy of the PSL trapping center is 0.78 eV and that of the TL trapping center is 0.79 eV. We, thus, suggest that the trapping centers giving rise to the PSL are identical to those giving rise to the TL.

Ac/Ds Mediated Gene Trapping System in Rice

  • Yi, Gi-Hwan;Nam, Min-Hee;Han, Chang-Deok;Kim, Ho-Young;Moon, Huhn-Pal
    • 한국생명과학회:학술대회논문집
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    • 한국생명과학회 2001년도 제31회 학술심포지움 및 춘계학술대회
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    • pp.85-85
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    • 2001
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Field Effect Transistor of Vertically Stacked, Self-assembled InAs Quantum Dots with Nonvolatile Memory

  • Li, Shuwei;Koike, Kazuto;Yano, Mitsuaki
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제2권3호
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    • pp.170-172
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    • 2002
  • The epilayer of vertically stacked, self-assembled InAs Quantum Dots (QDs)was grown by MBE with solid sources in non-cracking K-cells, and the sample was fabricated to a FET structure using a conventional technology. The device characteristic and performance were studied. At 77K and room temperature, the threshold voltage shift values are 0.75V and 0.35 V, which are caused by the trapping and detrapping of electrons in the quantum dots. Discharging and charging curves form the part of a hysteresis loop to exhibit memory function. The electrical injection of confined electrons in QDs products the threshold voltage shift and memory function with the persistent electron trapping, which shows the potential use for a room temperature application.

몬테카를로 방법을 이용한 AC PDP 셀의 진공자외선 광자 이동 특성 해석 (Analysis of Vacuum UV Photon Travel Characteristics in AC PDP Cell by Monte Carlo Simulation)

  • 김정호;정희섭;이병호;황기웅
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권9호
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    • pp.634-640
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    • 1999
  • Resonance radiation trapping has a great influence on the characteristics of vacuum ultraviolet(VUV) photon emissions in AC PDP cell. We calculate the spatial andspectral distributions of VUV photons, which are radiated by excited Xe in AC PDP cell by Monte Carlo method. Especially a dip in the spectrum at center frequency is discovered both in simulation and in experiment. We give a physical explanation of this phenomenon by the concept of frequency-dependent mean free path of VUV photons.

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