• Environmental Engineering Research
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• v.25 no.4
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• pp.447-461
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• 2020

In recent years, stimuli-responsive materials have garnered interest due to their ability to change properties when exposed to external stimuli, making it useful for various applications including gas separation. Light is a very attractive trigger for responsive materials due to its speedy and non-invasive nature as well as the potential to reduce energy costs significantly. Even though light is deemed as an appealing stimulus for the development of stimuli-responsive materials, this avenue has yet to be extensively researched, as evidenced by the fewer works done on the photo-responsive membranes. Of these, there are even less research done on photo-responsive materials for the purpose of gas separation, thus, we have collected the examples that answer both these criteria in this review. This review covers the utilisation of photo-responsive materials specifically for gas separation purposes. Photo-chromic units, their integration into gas separation systems, mechanism and research that have been done on the topic so far are discussed.

• Bulletin of the Korean Chemical Society
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• v.23 no.10
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• pp.1470-1472
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• 2002

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.980-983
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• 2006

New blue light emitting branched molecules were synthesized by reacting 3,5-bis-(3,5-bis-benzyloxy)- benzoic moiety or 3,5-bis-(3,5-bis-benzyloxy-benzyloxy)- benzoic moiety with biscarbazolyl vinyl biphenyl moiety by dicyclohexylcarbodiimide (DCC) catalyzed esterification. Similar synthetic strategy was also applied to prepare a red light emitting dendrimer. In this paper, we described two blue emitting dendrimers for investigating the effect of the dendronized structures on photoluminescence (PL) and electroluminescence (EL). EL properties of the dendrimers were investigated using heterostructured samples in detalil.

• Journal of Photoscience
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• v.8 no.2
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• pp.79-82
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• 2001

2-(p-Diethylaminostyryl)pyrrole (I) and 2-[5-diethylaminothienyl]vinyl]pyrrole (II) derivatives with systematic variation of the acceptors have been synthesized and their first hyperpolarizabilities were measured. The $\beta$ values increased systematically as the aromatic resonance energy decreased. Moreover, the value of $\beta$ for the former increased gradually as the acceptor strength increased. The opposite trend observed in the latter series of compounds has been attributed to the distorted structure caused by the steric hindrance between the N-methyl group and the acceptor moiety.

• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.169-184
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• 2006

A review is made on the chemical vapor deposition polymerization (CVDP) of insoluble and infusible poly(arylenevinylene)s and its applications to nanoscience. Poly(p-phenylenevinylene) (PPV), poly(naphthylenevinylene)s, poly(2,5-thinenylenevinylene) (PTV), and other homologous polymers containing oligothiophenes could be prepared by the CVDP method in the form of films, tubes, and fibers of nano dimensions. They would be readily converted to graphitic carbons of different structures by thermal treatment. Field emission FE) of carbonized PPV nanotubes, photoconductivity of carbonized PPV/PPV bilayer nanotubes and nanofilms also were studied.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.31-32
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• 2004

• Macromolecular Research
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• v.13 no.6
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• pp.477-482
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• 2005

Photopolymers are attractive materials for holographic 3-D data storage because of their high photosensitivity and large refractive index modulation. We synthesized the six-armed dendrimer for fabricating the new photopolymer. It was prepared using the initiating mixture of hexaarylbiimidazole (HABI), mercapto-benzoxazole (MOBZ), and 2,6-bis(4-diethylaminobenzylidene)cyclopentanone (DEAW), which is sensitive to 514 nm wavelength. The holographic gratings were fabricated successfully in these photopolymer samples by conventional optical interference method. We investigated the effect of dendrimer, either as a binder or as a plasticizer in the cellulose acetate butyrate (CAB), on the diffraction behavior. The addition of only 1 wt$\%$ of dendrimer-I into the CAB significantly increased the diffraction efficiency. The sample doped with dendrimer showed around 80-83$\%$ of the diffraction efficiency.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.3-4
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• 2006

Natural DNAs in dry state, i.e., A-DNAs, when intercalated with low levels of stable organic free radicals or complexed with low levels of Au(III), are attracted at room temperature to commercial magnets, whereas those containing high levels of intercalators or Au(III) are not. This surprising observation is explained by the EPR spectra and SQUID measurement of magnetization of the modified DNAs. It is conjectured that A-DNAs are morphologically heterogeneous containing ordered and disordered regions. The ordered regions appear to strongly mediate magnetic interactions between spins through their ${\pi}_z$-stacked structures. When the modified DNAs are wet or hydrated, they behave diamagnetically.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.170-173
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• 2007

Cruciform conjugated molecule, 4(DP3T)-benzene bearing terthiophene moieties has been synthesized through Horner-Emmons Reaction using 5-dodecyl-5"-aldehyde-[2,2';5',2"] terthiophene as dendrons and octaethyl benzene- 1,2,4,5-tetrayltetrakis(methylene)tetraphosphonate as the core unit; this molecule has been fully characterized. The terthiophene-based molecule exhibits good solubility in common organic solvents and good self-film forming property. They are intrinsically crystalline as they exhibit well-defined X-ray diffraction patterns from uniform orientations of molecules. Thus, intermolecular interaction can be enhanced to affect the carrier transport phenomena after annealing at $148^{\circ}C$. The semiconducting property of 4(DP3T)-benzene have been evaluated in organic field-effect transistors. 4(DP3T)-benzene exhibit carrier mobility as high as $(6.6{\pm}0.5)$ ${\times}$ $10^{-6}cm^2V^{-1}s^{-1}$.

• Macromolecular Research
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• v.14 no.6
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• pp.603-609
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• 2006

Tricyanopyrrolidene chromophores were prepared in order to compare their macroscopic nonlinear optical (NLO) properties with a conjugated structure through the long molecular axis. A thiophene or phenyl ring was tethered to an ethylenic bond; it may act as a lateral moiety to disrupt the planarity of a chromophore and lessen the electrostatic interaction. Thin film composites of these chromophores dissolved in amorphous polycarbonate (APC) were fabricated. Real time pole and probe method was employed to investigate the change of electro-optic (EO) signal during poling. The EO properties and their relaxation behaviors of the guest-host systems containing newly synthesized chromophores were investigated in detail.