• Transactions on Electrical and Electronic Materials
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• 제8권6호
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• pp.250-254
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• 2007

Applying the moving photo-carrier grating(MPG) technique and time-of-flight(TOF) measurements, we studied the transport properties of stabilized amorphous selenium typical of the material used in direct conversion X-ray imaging devices. For MPG measurement, we obtained electron and hole mobility and the recombination lifetime of $\alpha-Se$ films with arsenic(As) additions. We found an apparent increase in hole drift mobility and recombination lifetime, especially when 0.3 % As was added into $\alpha-Se$ film, whereas electron mobility decreased with the addition of As due to the defect density. For TOF measurement, a laser beam with pulse duration of 5 ns and wavelength of 350 nm was illuminated on the surface of $\alpha-Se$ with a thickness of 400 ${\mu}m$. The measured hole and electron transit times were about 8.73 ${\mu}s$ and 229.17 ${\mu}s$, respectively.

• 한국인터넷방송통신학회논문지
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• 제15권3호
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• pp.59-65
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• 2015

최근 네트워크 산업계에서 기존 전송 망 보다 유연한 망을 구축하기 위한 캐리어이더넷 기술이 부각되고 있으며 MPLS-TP (MultiProtocol Label Switching-Transport Profile) 기술이 해당 영역의 주요 표준 기술로 적용되고 있다. 하지만 MPLS-TP 망내의 장비를 관리하기 위한 관리 망에 대해서는 명확하지 않은 상태이다. 본 논문에서는 MPLS-TP 망 내의 장비 설치 시 부가적 설정 없이 자동으로 관리 망을 구축하는 방안을 제안한다. 제안하는 방법으로 관리시스템과 망 연결을 위한 설정을 최소화 하여 망 내의 장치 설치비용과 유지 관리 비용을 감축할 수 있다. 또한 실제 MPLS-TP 장비에 적용하여 제안하는 방법의 실효성에 대해 검증하였다.

• 대한전자공학회논문지TE
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• 제37권1호
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• pp.27-34
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• 2000

본 논문에서는 SCH 양자우물 구조를 가진 레이저 다이오드에서의 캐리어 수송기구와 변조응답 특성에 대해 고찰하였다. 캐리어 수송구조 고찰을 위해 캐리어 밀도분포및 다이오드전류를 계산하였다. 또한 우물내에서의 캐리어 재결합율을 SCH길이의 함수로 도출하였다. 변조응답 특성에서는 캐리어와 광자에 대한 3쌍의 비율 방정식을 도출, 해석하여 SCH 길이에 따른 변조 대역폭과 완화 진동 주파수, 감쇄 비율과 K-factor의 특성에 대하여 고찰하였다.

• BMB Reports
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• 제37권5호
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• pp.515-521
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• 2004

The tricarboxylate (or citrate) carrier was purified from eel liver mitochondria and functionally reconstituted into liposomes. Incubation of the proteoliposomes with various sulfhydryl reagents led to inhibition of the reconstituted citrate transport activity. Preincubation of the proteoliposomes with reversible SH reagents, such as mercurials and methanethiosulfonates, protected the eel liver tricarboxylate carrier against inactivation by the irreversible reagent N-(1-pyrenyl)maleimide (PM). Citrate and L-malate, two substrates of the tricarboxylate carrier, protected the protein against inactivation by sulfhydryl reagents and decreased the fluorescent PM bound to the purified protein. These results suggest that the eel liver tricarboxylate carrier requires a single population of free cysteine(s) in order to manifest catalytic activity. The reactive cysteine(s) is most probably located at or near the substrate binding site of the carrier protein.

• Macromolecular Research
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• 제12권6호
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• pp.598-603
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• 2004

Cellulose nitrate (CN) composite membranes, containing cobalt porphyrin (CoP) complexes self-assembled within nanometer-sized rhenium clusters (ReCoP), have been prepared and their oxygen and nitrogen gas perme­abilities were analyzed. The solubility of ReCoP and the characteristics of the corresponding composite membranes were analyzed using a Cahn microbalance, FT-IR spectroscopy, wide-angle X-ray scattering, and differential scanning calorimetry. The nitrogen permeability through the CN composite membranes decreased upon addition of ReCoP and CoP, which implies that the presence of these oxygen carrier complexes affects the structure of the polymer matrix. The oxygen permeability through the composite membranes containing small quantities of ReCoP decreased, but it increased upon increasing the concentration. The oxygen gas transport was affected by the matrix at low ReCoP concentrations, but higher concentrations of ReCoP increased the oxygen permeability as a result of its reversible and specific interactions with oxygen, effectively realizing ReCoP carrier-mediated oxygen transport.

• 대한화학회지
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• 제28권3호
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• pp.170-175
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• 1984

Dibenzo-18-crown-6(DBC) 및 dicyclohexyl-18-crown-6(DCC)를 이온의 운반체로 하는 여러 유기액체막을 통해 수소이온의 운반속도를 25$^{\circ}$C에서 측정하였다. 운반속도는 용매의 유전상수에 크게 영향을 받는데 이를 액체막 내부에서 이온 화학종이 가진 Born의 포텐셜 에너지 장벽을 들어 고찰하였다. 또한 음이온의 크기도 운반속도에 영향을 주었는데 이는 Born식으로 부터 새로이 유도된 이론적인 결과와 잘 일치하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.432.2-432.2
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• 2014

Recently, colloidal core/shell type quantum dots lighting-emitting diodes (QDLEDs) have been extensively studied and developed for the future of optoelectronic applications. In the work, we fabricate an inverted CdSe/ZnS quantum dot (QD) based light-emitting diodes (QDLED)[1]. In order to reduce work function of indium tin oxide (ITO) electrode for inverted structure, a very thin (<10 nm) polyethylenimine ethoxylated (PEIE) is used as surface modifier[2] instead of conventional metal oxide electron injection layer. The PEIE layer substantially reduces the work function of ITO electrodes which is estimated to be 3.08 eV by ultraviolet photoemission spectroscopy (UPS). From transmission electron microscopy (TEM) study, CdSe/ZnS QDs are uniformly distributed and formed by a monolayer on PEIE layer. In this inverted QD LED, two kinds of hybrid organic materials, [poly (9,9-di-n-octyl-fluorene-alt-benzothiadiazolo)(F8BT) + poly(N,N'-bis (4-butylphenyl)-N,N'-bis(phenyl)benzidine (poly-TPD)] and [4,4'-N,N'-dicarbazole-biphenyl (CBP) + poly-TPD], were adopted as hole transport layer having high highest occupied molecular orbital (HOMO) level for improving hole transport ability. At a low-operating voltage of 8 V, the device emits orange and red spectral radiation with high brightness up to 2450 and 1420 cd/m2, and luminance efficacy of 1.4 cd/A and 0.89 cd/A, respectively, at 7 V applied bias. Also, the carrier transport mechanisms for the QD LEDs are described by using several models to fit the experimental I-V data.

• Bulletin of the Korean Chemical Society
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• 제24권4호
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• pp.489-493
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• 2003

2-Mercaptobenzothiazole was used as a highly selective and efficient carrier for the uphill transport of silver ion through a chloroform bulk liquid membrane. In the presence of thiosulfate ion as a suitable metal ion acceptor in the receiving phase, the amount of silver transported across the liquid membrane after 180 min was 90 ± 3.0%. The selectivity and efficiency of silver ion transported from aqueous solutions containing equimolar mixtures of $Zn^{2+}, Cu^{2+}, Co^{2+}, Ni^{2+}, Cd^{2+}, Pb^{2+}, Bi^{3+}, Fe^{2+}, Fe^{3+}, Pd^{2+}, Mn^{2+}, Hg^{2+}, Sn^{2+}, Ca^{2+}, Mg^{2+}, K^+, Na^+ and Li^+$ were investigated.

• 한국전기전자재료학회논문지
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• 제17권12호
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• pp.1341-1346
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• 2004

The OLED research is gone for two directions. One is material development research, and another one is structural improvement part. All two are thing to heighten luminescence efficiency of OLED. n other to improve luminescence efficiency of OLED Electron - hole pairs must consist much more in the device Their profiles are sensitive to mobility velocity of electrons and holes. In this paper, we demonstrate the difference of velocity between hole and electron by experiments, and compare with a data of simulation and experiment changing hole carrier transport layer thickness, so we get the optimal we improve luminescence efficiency. We suggest improving the efficiency of OLEDS would be to balance the injection of electrons and holes into light emission layer of the device. And, we improve understanding of the various luminescence efficiency through experiments and numerical analysis of luminescence efficiency in variable hole carrier transport layer's thickness.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1002-1006
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• 2004

The studies on OLED(Organic Light-Emitting Diode) materials and structures have been researched in other to improve luminescence efficiency of OLED. Electrons and holes are injected into the devices, transported across the layer and recombine to form excitons, their profiles are sensitive to mobility velocity of electrons and holes. A suggested means of improving the efficiency of LEDs would be to balance the injection of electrons and holes into light emission layer of the device. In this paper, we demonstrate the difference of velocity between hole and electron by experiments, and compare with a data of simulation and experiment changing hole carrier transport layer thickness, so we get the optimal we improve luminescence efficiency. We improve understanding of the various luminescence efficiency through experiments and numerical analysis of luminescence efficiency in the hole carrier transport layer's thicknes.