• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.269-271
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• 2004

In this report, high-performance organic light-emitting diodes (OLEDs) with polytetrafluoroethylene (Teflon) buffer layer are demonstrated. Compared with conventional buffer layer, copper phthalocaynine (CuPc), Teflon film shows lower absorption in the wavelength from 200nm to 800nm The OLEDs with Teflon and CuPc buffer layer were fabricated under same conditions, and the device performances were compared. The results indicate that when the thickness of Teflon is 1.5nm, the performance of OLEDs is greatly enhanced with an efficiency of 9.0cd/A at the current density of 100mA/$cm^2$, while the device with an optimized 30-nm-thick CuPc buffer layer only shows an efficiency of6.4cd/A at the same current density.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.164-164
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• 2006

Polymeric photorefractive materials exhibit two attractive features, the large refractive index modulation (up to the order of $10^{-2}$) and the optical erasabilility of recorded holographic information. These advantages make the organic photorefractive materials to become candidates for optical data processing, e.g., pattern recognition and fingerprint verification. In this work, we demonstrate optically controlled SLMs using photorefractive composite. An incoherent image imposed in Xe-lamp light was converted into a coherent image.

• 공업화학
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• 제16권5호
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• pp.719-723
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• 2005

Tetraethyl orthosilicate (TEOS) 혹은 1,2-bis(triethyoxysilyl)ethane (BTSE)과 여러 종류의 organosilane들을 공중합하여 유 무기 혼성 메조포러스 물질들을 제조하고, 이들이 공기 중의 휘발성 유기화합물(VOC)들을 흡착 제거하는 능력을, TEOS 만을 사용하여 제조한 친수성 무기 메조포러스물질인 SBA-15와 비교 평가하였다. 유기 구조의 도입에 의한 소수성의 증대는 메조포러스 물질이 VOC를 흡착 제거하는데 긍정적 효과를 줌을 관찰하였다. 특히 BTSE와 phenyl triethoxysilane을 중량비 90:10으로 공중합한 유 무기 혼성 메조포러스 물질의 VOC 제거 능력은 우수하였다. 또, 물속에 분산된 기름 성분을 흡착 제거하는데 유 무기 혼성 메조포러스 물질들을 유용하게 응용할 수 있음도 정성적으로 관찰하였다.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1946-1950
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• 2009

Tripod-shaped liquid crystals with $sp^3$ nigrogen at the apex were prepared from triethanolamine. Their physical properties were investigated by using optical microscopy, differential scanning calorimetry, and X-ray diffraction measurements. The XRD study suggests that the tripod-shaped molecules show the 2D-ordered phase of either the frustrated smectic layer structure or discotic columnar phases.

• 대한화학회지
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• 제60권3호
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• pp.194-202
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• 2016

Two conjugated semiconducting copolymers consisting of 4,7-bis(4-(2-ethylhexyl)-2-thiophene)-2,1,3-benzothiadiazole (DTBT) and benzo[1,2-b:4,5-b']dithiophene with 5-(2-ethylhexyl)-2,2'-bithiophene (BDTBT) or 5-(2-ethylhexylthio)- 2,2'-bithiophene (BDTBT-S) were designed and synthesized as donor materials for organic photovoltaic cells (OPVs). Alkylthio-substituted PBDTBT-S-DTBT showed a higher hole mobility and lower highest occupied molecular orbital (HOMO) energy level (by 0.08 eV) than the corresponding alkyl-substituted PBDTBT-DTBT. An OPV fabricated using PBDTBT-S-DTBT showed higher V_OC and J_SC values of 0.83 V and 7.56 mA/cm², respectively, than those of a device fabricated using PBDTBT-DTBT (0.74 V) leading to a power conversion efficiency of 2.05% under AM 1.5G 100 mW/cm² illumination.

• Natural Product Sciences
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• 제24권3호
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• pp.155-158
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• 2018

A new flavonol derivative, meliglabrin (1) along with three known flavonols, ternatin (2), meliternatin (3), and 5,4'-dihydroxy-3,7,3'-trimethoxyflavon (4) were isolated from the leaves of Melicope glabra (Blume) T.G. Hartley. Their structures were determined using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1 - 4 were evaluated for their cytotoxicity against murine leukemia P-388 cells, compound 4 showed moderate activity.

• Macromolecular Research
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• 제17권7호
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• pp.491-498
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• 2009

New $\pi$-conjugated multi-branched molecules were synthesized through the Homer-Emmons reaction using alkyl-substituted, 3,4-ethylenedioxythiophene-based, thiophenyl aldehydes and octaethyl benzene-l,2,4,5-tetrayltetrakis(methylene) tetraphosphonate as the core unit; these molecules have all been fully characterized. The two multi-branched conjugated molecules exhibited excellent solubility in common organic solvents and good self-film forming properties. The semiconducting properties of these multi-branched molecules were also evaluated in organic field-effect transistors (OFET). With octyltrichlorosilane (OTS) treatment of the surface of the $SiO_2$ gate insulator, two of the crystalline conjugated molecules, 7 and 8, exhibited carrier mobilities as high as $2.4({\pm}0.5){\times}10^{-3}$ and $1.3({\pm}0.5){\times}10^{-3}cm^2V^{-1}s^{-1}$, respectively. The mobility enhancement of OFET by light irradiation ($\lambda$ = 436 nm) supported the promising photo-controlled switching behavior for the drain current of the device.

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.292-294
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• 2007

• Bulletin of the Korean Chemical Society
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• 제34권1호
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• pp.291-294
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• 2013

• 대한화학회지
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• 제55권5호
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• pp.787-793
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• 2011

An efficient three-component one-step synthesis of 2,4,5-trisubstituted imidazoles by condensation reaction of 1,2-diketones or ${\alpha}$-hydroxyketones with aromatic aldehydes and ammonium acetate using Zinc (II) [tetra (4-methylphenyl)] porphyrin as a novel and reusable catalyst under ultrasound irradiation at ambient temperature is described. In this method, ${\alpha}$-hydroxyketones as well as 1,2-diketones were converted to their corresponding 2,4,5-trisubstituted imidazoles in excellent yields.