• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.657-659
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• 2004

Trivalent cerium ($Ce^{3+}$) activated yttrium aluminum garnet ($Y_3Al_5O_{12}$, YAG) phosphor thin films were deposited on quartz glass substrates by rf magnetron sputtering. The effects of sputtering parameters and annealing condition on the luminescent properties were investigated. The sputtering parameters were $O_2$/Ar gas ratio, rf power, and deposition time. The films were annealed at 1200 $^{\circ}C$ for 5 hours in $N_2+$vacuum atmosphere. Polycrystalline YAG:Ce thin film phosphor could be obtained with a gas ratio of $O_2$/(Ar+$O_2$)=0.5 after post-annealing. PL spectra excited at 450 nm showed a yellow single band at 550 nm.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.654-656
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• 2004

The effect of excitation energy and various dopants(Eu and Ce) on the emission wavelength and intensity were investigated. According to PL spectra, SrO-$Al_2O_3$ phosphors had wide absorption band at nUV. By substituting Ce for Eu, the emission band and excitation wavelength were shifted to shorter wavelength. Ce doped $SrAl_2O_4$ and $Sr_4Al_{14}O_{25}$ showed greenish blue(475nm) and blue(400nm), respectively.

• Natural Product Sciences
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• v.10 no.2
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• pp.69-73
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• 2004

Continuation of a phytochemical study of Cichorium intybus L. (Astraceae) growing in Egypt, resulted in the isolation and identification of a new sesquiterpene lactone 3,4-dihydrolactucin, in addition to the eight known compounds; kaempferol, isoscutellarin, cichoriin, umbelliferone, lupeol, lupeol acetate, ${\beta}-sitosterol$, and ${\beta}-sitosterol-3-O-glucoside$. Chemical structures of the isolated compounds were assigned based on different physical, chemical, and spectroscopic techniques including IR, UV, MS, 1D- and 2D-NMR spectra. Furthermore, the antimicrobial, and spasmogenic activities of some fractions and isolates were also assessed.

• Mycobiology
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• v.28 no.4
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• pp.193-196
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• 2000

Thirty-eight species in addition to 2 varieties (3 unidentified) of zoosporic organisms belonging to 14 genera of Oomycetes and 3 genera of Chytridiomycetes were recovered from 50 soil samples randomly collected from different localities in the western region of Saudi Arabia. Allomyces and Dictyuchus have the highest frequency of occurrence while Achlya, Aqualinderella, Saproleginia and Phytophthora were of moderate occurrence, The remaining genera were less frequent. Seven species and two varieties were new records to Saudi Arabia, which are Achlya oblongata, Allomyces javancius var. allomorphus, Aphanomyces stellatus, Blastoccladia gracile, Dictyuchus magnusii, Olpidiopsis Saproleginia var. levis, Olpidium species, Phytophthora megasperma, and Saproleginia turfosa. Water and organic matter contents of soil samples are considered as major factors influencing the prevalence and occurrence of zoosporic organisms.

• Transactions on Electrical and Electronic Materials
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• v.14 no.5
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• pp.263-267
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• 2013

New random copolymers of phenylsilyl- and alkoxy-substituted phenylenevinylene, DMPS(9)-MEH(1)-PPV, DMPS(5)- MEH(5)-PPV and DMPS(1)-MEH(9)-PPV, have been synthesized by the Gilch dehydrohalogenation route, and the light-emitting properties of these polymers have been studied. The synthesized polymers were completely soluble in common organic solvents, and exhibited good thermal stability, almost up to $380^{\circ}C$. They showed UV-visible absorbance and photoluminescence (PL) in the ranges of 422-510 and 513-590 nm, respectively, according to their feed ratios. Electroluminescent devices were fabricated with these polymers as emitting layers, and ITO and Al as anode and cathode, respectively. DMPS(1)-MEH(9)-PPV, DMPS(5)-MEH(5)-PPV and DMPS(9)-MEH(1)-PPV exhibited EL emission maxima at 575 nm, 565 nm, and 541 nm, respectively.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1353_1354
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• 2009

The OTFT devices had inverted staggered structures of Au/pentacene/ppMMA/ITO on PET substrate. The overall device performances of the flexible devices such as the operating voltage, the field effect mobility, the on/off ratio and the off current are somewhat worse than those of devices fabricated on glass substrates. Pentacene/ppMMA OTFT benchmarks (mobility, sub-threshold slope, on/off ratio) were comparable to that of solution cast PMMA, but below average when compared to other polymer gate dielectrics. However, threshold and drive voltages were among the lowest reported for a polymer gate dielectric, and surpassed only by ultra-thin SAM gate dielectrics.

• Journal of the Korean Graphic Arts Communication Society
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• v.13 no.2
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• pp.1-17
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• 1995

Organic thin film electroluminescene devices were fabricated using by molecularly doped method with N,N`-diphenyl-N,N`-bis(3-methylphenyl)-1,1`-biphenyl-4,4`-diamine(TPD) as a hole transport material, tris(8-quinolinolate) aluminium(III)(Alq3) as an emitting and electron transport agent, fluorescent squarylium(SQ) dye as a dopant, and poly(methylmethacrylate) as polymer materials. A cell structure of ITO/TPD-PMMA/Alq3-dopant/Mg was employed. The EL spectrum covers a wide range of the visible region and orange emission os observed. Two peaks at 520 and 660nm correspond to the emissions 620nm Alq3 and SQ dye, respectively.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.783-785
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• 1998

In this study the emission characteristics of Sq dye undoped and doped specimen investigated. In Sq 14mol% doped specimen, OXD7 and Alq3 layer interpolated. This effect has been observed and mechanism characteristics have been examined. For OXD7 insert, hole flow the cathode intercept, and then hole accumulated. Because of increasing recombination probability of electron and hole highly pure color maintained. Simultaneously brightness characteristics and emission efficiency could improve.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.454-457
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• 2008

We report the syntheses, photophysical properties and device performances of solution processible host material for green-phosphorescent OLEDs. The butterfly-shaped new host materials with nonconjugated linkage of carbazole and fluorene moieties have large triple energy band gap around 2.8 eV. All of the EL devices exhibited turn-on voltages in the range of 4.8-5.0 V. GH-4 exhibited the best performance with a maximum current efficiency and power efficiency of 21.1 cd/A and 7.9 lm/W.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1018-1023
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• 2006

The metal chelate complex of aluminum 8-hydroxyquinolines $(Alq_3)$ is an important electro-luminescent (EL) material used in fabricating organic light emitting (OLEDs). In this work, diodes / displays using in house synthesized $Alq_3$ and simple structure have been fabricated. It is demonstrated that luminance of $12460\;cd/m^2$ and efficiency of 3.1 cd/A are achievable in these fluorescent devices. Possible degradation effects are analyzed.