• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2415-2418
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• 2008

Polydiacetylenes (PDAs) are very attractive chemical substances which have distinctive features of color change and fluorescence emission by thermal or chemical stress. Especially, when PDAs contact with solutions of a particular pH, such as a strong alkaline sodium hydroxide (NaOH) solution or a strong acidic hydrogen chloride (HCl) solution, PDAs change their color from non-fluorescent blue to fluorescent red. In this study, we propose a novel method to detect alkaline pH using PDAs and NaOH solutions by hydrodynamic focusing on a microfluidic chip. Preliminary results indicate that the fluorescent intensity of PDAs increases in respond to the NaOH solution concentrations. Also, the fluorescence is quenched back when the PDAs are in contact with a HCl solution. These results are useful in a microfluidic PDA sensor chip design for pH detection.

• 천문학회보
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• 제37권2호
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• pp.88.2-88.2
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• 2012

We present kinematic properties of the narrow-line region in three type-2 QSOs at z~0.35, using 2-D spectra obtained with the VIMOS integral field unit spectrograph at the Very Large Telescope. One of the objects shows a line-of-sight velocity shift of the [OIII] and $H{\beta}$ lines up to 40km/s on a 15 kpc scale, which can be interpreted as either outflow or rotation. The outflow scenario is supported by the presence of blue wings and a radio structure showing lobes in the same direction. Another object features double-peaked emission lines which can be decomposed into two velocity components. Its Hubble Space Telescope image shows two nuclei separated by ~0.2"(~1kpc), implying this may be a binary AGN.

• Macromolecular Research
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• 제13권4호
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• pp.334-338
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• 2005

A three-layered poly(benzyl ether) dendrimer having a bis-ethynylbenzene core was synthesized and characterized with $^{1}H$ NMR and MALDI-TOF-MS spectroscopy. The dendrimer was reacted with platinum complexes to obtain platinum-acetylide based organometallic polymers. When the dendrimer was reacted with trans-[$PtCl_{2}(PEt_{3})_{2}$], a high molecular weight polymeric compound was formed, whereas, with cis-[$PtCl_{2}dppp$], a uniform molecular weight compound was formed, which was found to be a dimeric metallacycle by $^{1}H\;NMR,\;^{31}P\;NMR$ and ESI-TOF-MS spectroscopy. Both these complexes exhibited relatively a strong emission around 440 nm, indicating that they could be potential candidates for blue emitting polymer LEDs.

• Applied Science and Convergence Technology
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• 제23권5호
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• pp.296-300
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• 2014

The synthesis of pure and rare-earth doped gallium oxide (${\beta}-Ga_2O_3$) nanoparticles is reported. The synthesized nanoparticles are characterized with XRD, TEM, and PL analyses. Strong blue emission is observed from un-doped gallium oxide nanoparticles, while nanoparticles doped with $Eu^{3+}$ and $Tb^{3+}$ give strong red and green emissions, respectively. When doped with $Eu^{3+}$ and $Tb^{3+}$ together, gallium oxide nanoparticles emit white light. The CIE coordinate of the emitted light was found to be (0.33, 0.33), which is well within the white light region.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.163-166
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• 1997

Electroluminescent(EL) dcvice based on organic thin layers have attracted lots of interests because of thier possible application as large-area light-emitting displays. It was known that MEH-PPV and 1, 1, 4, 4, -Tetraphenyl-1, 3-butadiene(TPB) has red and blue emission peak at 580nm and 480nm, respectively. In this study, MEH-PPV films and TPB films were prepared by spin coating and vacuum deposition method, respectively. Films of MEH-PPV and TPB double layer were also prepared by the same method. Photoluminescent(PL) characteristics of these single and doubler layers were investigated, where a cell structure of glass substrate/ITO/MEH-PPV and/or TPB/Al was employed. It was found that the photoluminescent efficiency of TPB film was higher than that of MEH-PPV film with a single layer and also with a double structure. These films have also different I-V characteristics.

• 한국전기전자재료학회논문지
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• 제23권2호
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• pp.124-127
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• 2010

We have fabricated organic white light emitting device by two colors from yellow fluorescence material (5,6,11,12)-Tetraphenylnaphthacene(Rubrene) and blue phosphorescent material (iridum-bis(4,6-difluorophenylpyridinato-N,C2)-picolinate(FIrpic). The threshold voltage is 5.3 V, and the brightness reaches 1000 cd/$m^2$ at 11 V, 14.5 mA/$m^2$. The color of the light corresponds to a CIE coordinate of (0.30, 0.38). The highest efficiency of the device can reach 9.5 cd/A or 5.5 lm/W at 6 V, 0.1 mA/$m^2$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.428-429
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• 2005

Novel fluoroionophore of dibenzothiazolyl-dibenzo-crown ethers were synthesized from diformal-dibenzo 18-crown-6 (24-crown-8) with 2-aminothiophenol, and they were characterizated by $^1H$-NMR, $^{13}C$-NMR, IR spectrum, Mass spectrum, elemental analyses, respectively. The fluorescent properties of the newly synthesized crown ether were examined with $Li^+$, $Na^+$, $K^+$, $Rb^+$, $Cs^+$, $NH_4^+$ and $CF_3COOH$, respectively. With protonation using $CF_3COOH$, the absorption bands of the new crown ethers are further blue shifted, the maximum emission wavelengths further red shifted.

• Macromolecular Research
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• 제16권4호
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• pp.360-366
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• 2008

Poly(dialkoxyphenylene 1,3,4-oxadiazole)s were conveniently synthesized to compare their material properties of solvent solubility, thermal stability and molecular alignment with respect to alkyl chain length and meta/para-phenylene structure. All prepared polymers exhibited good solubility in co-solvents containing various volume levels of chloroform to trifluoroacetic acid. Meta-polymers showed slightly better solubility than para-polymers. All polymers produced were thermally stable up to $320^{\circ}C$. Photoluminescence of polymer films was observed with blue light emission at around 450 nm. X-ray diffraction patterns of all polymers indicated that they were composed of stacked molecular sheets with the same layer-to-layer distance of $3.4\;{\AA}$. However, side chain-to-side chain and main chain-to-main distances within the layers increased with increasing alkyl chain lengths. The meta-polymer chains were separated more than the para-polymer chains.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.137-137
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• 2010

Copper electroplating is a very popular and important technology for depositing high-quality conductor interconnections, especially in through silicon via (TSV). As this advanced packaging technique developing, a mass of copper and chemical solution are used, so attention to these chemical materials into the utilization and costs can not be ignored. An economical and practical real-time chemical solution monitoring has not been achieved yet. Either Red-green-blue (RGB) or optical emission spectroscopy (OES) color sensor can successfully monitor the color condition of solution during the process. The reaction rate, uniformity and quality can map onto the color changing. Hidden Semi Markov model (HSMM) can establish mapping from the color change to upper indicators, and artificial neural network (ANN) can be integrated to comprehensively determine its targets, whether the solution inside the container can continue to use.

• 한국해양바이오학회지
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• 제5권4호
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• pp.26-32
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• 2011

Green fluorescent protein (GFP), a very important biological agent that involves shifting the color of bioluminescence from blue to green in luminous coelenterates and to increase the quantum yield of light emission. GFP discovered in medusa, Aequorea victoria is a key factor of various biotechnological and cell biological applications. Beside these applications, GFP of A. victoria is generally stable, which does not require co-factors for activity and can be functionally expressed in different bacterial species. This property of GFPs from A. victoria permits them to be a unique tool to monitor gene expression and protein localization in different organisms. The present review brings out the past milestones and future perspectives on GFPs, with an elaborative reviewing on its applications.