• BMB Reports
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• v.41 no.3
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• pp.177-183
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• 2008

Ubiquitin is an essential, highly-conserved small regulatory protein in eukaryotic cells. It covalently modifies a wide variety of targeted proteins in the forms of monomer and polymers, altering the conformation and binding properties of the proteins and thus regulating proteasomal delivery, protein activities and localization. Mass spectrometry has emerged as an indispensable tool for in-depth characterization of protein ubiquitination. Ubiquitinated proteins in cell lysates are usually enriched by affinity chromatography and subsequently analyzed by mass spectrometry for identification and quantification. Ubiquitin-conjugated amino acid residues can be determined by unique mass shift caused by the modification. Moreover, the complex structure of polyubiquitin chains on substrates can be dissected by bottom-up and middle-down mass spectrometric approaches, revealing potential novel functions of polyubiquitin linkages. Here I review the advances and caveats of these strategies, emphasizing caution in the validation of ubiquitinated proteins and in the interpretation of raw data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.957-960
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• 2002

Electroluminescence(EL) from conjugated polymers has recently received great attention because polymer light-emitting diodes(LEDs) clealy have potential for applications such as large-area displays. The operation of polymer LEDs is based on double injection of electrons and holes from the elextrodes, followed by formation of excitons whose radiative decay results in light emission at wavelength characteristic to the material. In this paper, we fabricated the single layer EL device using $Alq_3$ as emitting material. According as turn on voltage could know about 5.5V in voltage-current characteristics and voltage rise, current could see that increase as non-linear. Current and ruminance can see that express similar relativity in voltage, and could know that ruminance is expressing current relativity.

• Macromolecular Research
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• v.8 no.5
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• pp.231-237
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• 2000

The polymerization of 3-ethynylphenol, phenylacetylene having hydroxy functionality, was carried out by tungsten and molybdenum-based transition metal catalysts. The polymerization proceeded to give a moderate yield of polymer. The effects on the mole ratio of monomer to catalyst (M/C), initial monomer concentration ((Mb), and the polymerization temperature for the polymerization of 3-ethynylphenol were investigated. The catalytic activity of W-based catalysts was found to be greater than that of Mo-based catalysts. The resulting polymers were brown or black powders and mostly insoluble in organic solvents. Structural analysis of the polymer by instrumental methods revealed the conjugated polymer backbone structure carrying hydroxyphenyl moieties. Thermal and morphological properties of the resulting poly(3-ethynylphenol) were also discussed.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.23-24
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• 2006

Magnetic and magneto-optical properties of regioregular (>99%) poly(3-dodecylthiopenes are investigated. Faraday rotation of spin-coated films show extremely large Verdet constants, falling strongly with decreasing regioregularity. EPR spectroscopy at room temperature shows the presence of about 1 spin/190 monomers, indicative of delocalisation beyond a single polymer chain. SQUID measurements on the polymer give an effective magnetic moment of about 48900 mB, corrsponding to a S-value of 25.000. The Weiss-constant is 1.33 K indicating ferromagnetic coupling. Our experimental results show that organic polymer magnets can be prepared. Large MO effects allow the use of these materials in all-organic MO-sensors and devices.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1419-1420
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• 2005

We have synthesized a photo patternable blue lightemitting polyfluorene (PF) derivative containing cross-linkable oxetane units. Poly(9,9-bis-(4-octyloxyphenyl)- fluorene-2,7-diyl-alt-9,9-bis-((3-hexyloxy-3'- ethyl)-oxetane)-fluorene-2,7-diyl) has been synthesized by Suzuki coupling polymerization. The relationship between patterning property and several variables such as the intensity of the exposed UV light, the concentrations of additives, has been studied by using optical microscope UV/visible spectroscopy, photoluminescence and scanning electron microscope (SEM). We obtained fine patterns with 10 mm resolution using the polymer film after exposure and development. This patterning method using conjugated polymers can be applicable to make fine pixels for PLEDs and OFETs.

• Journal of Information Display
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• v.6 no.1
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• pp.33-36
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• 2005

To obtain various colors from the blue emitting poly(fluorene)s, two different approaches are introduced. One is copolymerization with low band gap comonomers and the other is molecular doping with various dyes. As fast and efficient exciton migration and trapping and/or energy transfer between the chromorphoric segments or doped dyes in conjugated polymers can shift the emission to longer wavelengths, these phenomena can be utilized to obtain various colors from the intrinsically blue light emitting poly(fluorene)s.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.25-28
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• 1998

Since the first report on poly(p-phenylenevinylene), the electroluminescent properties of namy conjugated polymers such as poly(p-phenylenevinylene) (PPV), poythiophene (PT), poly(p-phenylene) (PPP), and polyfluorene (PF) have been investigated because of their potential for use in display technology However, in the application of polymer light-emitting diodes (PLEDs), there are yet three fundamental issues to be considered: (1) full color capability, (2) emission efficiency, (3) stability (lifetime). (omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.506-509
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• 2002

In this paper. we give pressure stimulation into organic ultra thin films and detected the induced displacement current proper ties, and then manufacture a device under the accumulation condition. In processing of a device manufacture. And electroluminescence(EL) from conjugated polymers has recently received great attention because polymer light-emitting diodes(LEDs) clealy have potential for applications such as large-area displays. The operation of polymer LEDs is based on double injection of electrons and holes from the elextrodes. followed by formation of excitons whose radiative decay results in light emission at wavelength characteristic to the material. In this paper, we fabricated the single layer EL device using $Alq_3$ as emitting material. According as turn on voltage could know about 5.5V in voltage-current characteristics and voltage rise, current could see that increase as non-linear, Current and ruminance can see that express similar relativity in voltage, and could know that ruminance is expressing current relativity.

• Polymer Science and Technology
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• v.18 no.4
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• pp.319-325
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• 2007

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.67-70
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• 2009

Printed electronics are emerging technology to realize various microelectronic devices via a cost-effective method. Here we introduce high performance inkjet printed polymer field-effect transistors and application to complementary integrated circuits with p-type and n-type conjugated polymers. The performance of devices highly depends on the selection of dielectrics, printing condition and device architecture. The device optimization and performances of various integrated circuits, e.g., complementary inverters and ring oscillators will be mainly discussed in this talk.