• ALGAE
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• 제20권3호
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• pp.225-232
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• 2005

Optical microscopy of recently living and cleared material of the fucoid, Ascophyllum nodosum (L.) Le Jolis, revealed novel aspects of its interaction with the ascomycete Mycophycias ascophylli (Cotton) Kohlmeyer and Kohlmeyer (previously Mycosphaerella ascophylli Cotton). Most host cells are associated with hyphae by lateral attachment of cell walls. Hyphae form extensive networks throughout the host thallus and show considerable differentiation in the various host tissues. In the base of epidermal cells, hyphae form multicellular rings around each host cell to produce a continuous network. In medullary regions, long, relatively unbranched and longitudinally aligned hyphae occur, with radial branches extending into cortical regions. Scattered in the inner cortex of host tissue are numerous multicellular nodes of smaller, polygonal to irregular shaped cells with five or more radiating arms of hyphae. Individual hyphal cells show a variety of specializations including swellings and appressoria-like attachments to some host cells. These observations provide the morphological basis for the mutualistic symbiosis supported by recent experimental work. We conclude that this association is best described by the term “symbiotum.”

• Transactions on Electrical and Electronic Materials
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• 제12권2호
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• pp.84-87
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• 2011

We fabricated phosphorescent organic light-emitting devices with a 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC) host layer. Two kinds of devices, one of ITO/TAPC/TAPC:FIrpic/TAZ/LiF/Al (device A) and one of ITO/TAPC:FIrpic/TAPC/TAZ/LiF/Al (device B), were prepared to investigate electrical and optical properties. Iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,$C^{2'}$]picolinate (FIrpic) and 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (TAZ) were used as a blue phosphorescent guest material and an electron transport layer, respectively. The TAPC layer in device B strongly contributes to whitish emission, higher driving voltage, and lower current efficiency characteristics compared with device A. The mechanisms of these electrical and optical characteristics of the devices were investigated.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.509-514
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• 2001

The Fibre-optic Bragg grating (FBG) sensor is broadly accepted as a structural health monitoring device for Fibre reinforced plastic (FRP) materials by either embedding into or bonding onto the structures. The accuracy of the strain measured by using the FBG sensor is highly dependent on the bonding characteristics among the bare optical fibre, protective coating, adhesive layer and host material. In general, the signal extracted from the embedded FBG sensor should reflect the straining condition of the host structure. This paper presents a theoretical model to evaluate the differential strains between the bare fibre and host material with different adhesive thickness and modulus of the protective coating of the embedded FBG sensor.

• 한국전기전자재료학회논문지
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• 제28권9호
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• pp.602-606
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• 2015

This paper presents a ZigBee wireless communication system for remote diagnosis in overhead distribution power lines. The system is divided in three parts in the functional aspect - a host computer module, a remote controller module and a diagnostic system module. The host computer module designed as USB interface transmits control signals and receive data measured by sensor. The remote controller module operates the diagnostic system. Diagnostic system module communicates with internal main controller and host computer USB. Multiple communication channel is adopted for simultaneous operations of several diagnostic system. Dedicated protocol for each module is developed. The system is designed with a focus on low cost and small size suitable for lightweight and small diagnostic system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.358-360
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• 2001

In this study, the bis(8-oxyquinolino)zinc II (Znq$_2$) were synthesized successfully from zinc chloride (ZnC1$_2$) as a initial material. Then, we fabricated red organic electroluminescent device with a dye (DCJTB)-doped and inserted Znq$_2$ between emission layer and cathode layer for increasing EL efficiency. The hole transfer layer is a N,N'-diphenyl-N,N'-bis-(3-methyl phenyl) -1,1'-diphenyl-4,4'- diamine(TPD), and the host material of emission layer is Znq$_2$. And we study the electrical and optical properties of devices. We found that the device using Znq$_2$ inserting layer result in the increased efficiency.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.903-906
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• 2003

Doping a small amount of a phosphorescent dye into an organic light-emitting diodes(OLED) can lead to a significant improvement in the device properties. The fluorescent host materials like TAZ, CBP have been used, but have a problem of rapid decay of efficiency at high current densities. To alleviate this problem, phosphorescent host was introduced. The whole configuration of OELD fabricated was ITO/a-NPD(50nm)/Zn $cluster:Ir(ppy)_{3}(30nm)/BCP{(10nm)/Alq_{3}(20nm)$ /Al:Li. The OLED showed high luminance (> 50,000 $cd/m^{2}$ ) and external efficiency(5.7%). At higher current densities, rapid decay of external quantum efficiency or host emission, which was frequently observed in the fluorescent host system, were not observed.

• Transactions on Electrical and Electronic Materials
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• 제12권2호
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• pp.80-83
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• 2011

We have fabricated phosphorescent white organic light-emitting devices (WOLEDs) with a spin-coated poly(Nvinylcarbazole) [PVK] host layer. Iridium(III) bis[(4,6-difluorophenyl)-pyridinato-N,$C^{2'}$]picolinate (FIrpic), tris(2-phenylpyridine)iridium(III) [$Ir(ppy)_3$], and tris(2-phenyl-1-quinoline)iridium(III) [$Ir(phq)_3$], were used as the blue, green, and red guest materials, respectively. The PVK was mixed with FIrpic, $Ir(ppy)_3$, and $Ir(phq)_3$ molecules in a chlorobenzene solution and spin-coated in order to prepare the emission layer; 3-(4-biphenylyl)-4-phenyl-5-(4-tertbutylphenyl)-1,2,4-triazole (TAZ) was used as an electron transport material. The resultant device structure was ITO/PVK:FIrpic:$Ir(ppy)_3:Ir(phq)_3$/TAZ/LiF/Al. The electroluminescence, efficiency, and electrical conduction characteristics of the WOLEDs based on the doped PVK host layer were investigated. The maximum current efficiency of the three wavelength WOLED with the doped PVK host was 19.2 cd/A.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권2호
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• pp.1573-1576
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• 2007

ABCV-Py, a new red fluorescent material, in which two identical electron donor (dimethylamino group) and acceptor (cyano group) moieties are linked to two independent biphenyl groups which share the same core phenyl, has been synthesized for use in OLED application. Performance of red doped electroluminescent devices using ABCV-Py as dopant were measured with various host materials, $Alq_3$, CBP, DPVBi, and p-terphenyl. The performance of device with DPVBi host material was better than those with other host materials and high doping concentration could be applied on device with ABCV-Py as dopant.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.214-217
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• 2002

The internal quantum efficiency of organic light emitting devices(OLEDs) using fluorescent organic materials is limited within 25% because of the triplet excitons which can hardly emit light. So there has been considerable interest in finding ways to obtain light emission from triplet excitons. One approach has been to add phosphorescent compounds to one of the layers in OLEDs. Then triplet excitons can transfer to these phosphorescent molecules and emit light. In this study, multilayer OLEDs with phosphorescent emitter, Iridium complexes were prepared. The devices with a structure of ITO/TPD/Ir complex doped in the host material/Alq3/Li:Al/Al were fabricated, and its electrical and optical characteristics were studied. Using various Ir complexes and the host materials, we fabricated several devices and investigated the device characteristics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.510-511
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• 2005

Several iridium based complexes were investigated as blue phosphorescent dopants. They are achieved about 100 % quantum efficiencies due to utilization of both singlet and triplet excitons in the radiative processes. We have fabricated phosphorescent OLED with 8 % Ir$(ppz)_3$ as a triplet emissive dopnat in diverse host materials. In this study, the CBP obtained the luminance efficiency of 0.20 cd/A adapts to the host material. Furthermore, we synthesize metalorganic phosphor complexs based on Ir heavy metal with different ligands as to $Ir(ppz)_2acac$, $(Im)_2Ir(acac)$, $(Im-R)_2Ir(acac)$.