• Applied Chemistry for Engineering
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• v.27 no.1
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• pp.86-91
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• 2016

Three amorphous silicas and SBA-15 were employed as supports, which were capable of confining ionic liquid (IL) and metallocene in the nanopore. Ionic liquid functionalized silica was prepared by the interaction between the chloride anions of 1,3-bis(cyanomethyl)imidazolium chloride and the surface OH groups. Metallocene and methylaluminoxane (MAO) were subsequently immobilized on the ionic liquid functionalized silica for ethylene polymerization. The metallocene supported on ionic liquid functionalized XPO-2412 and XPO-2410 having a larger pore diameter compared to SBA-15 showed higher activity than that of using supported catalyst without ionic liquid functionalization. However, the activity of metallocene supported on SBA-15 decreased after ionic liquid functionalization, suggesting that the diffusion of ethylene monomer and cocatalyst to the active site of nanopore was restricted during ethylene polymerization. This could be resulted from significant reduction of the pore diameter due to the immobilization of ionic liquid and $(n-BuCp)_2ZrCl_2$ and MAO. The effect on polymerization activity in accordance with the concentration of hydroxyl groups on the surface was also investigated. The polymerization activity increased as the concentration of hydroxyl groups on amorphous silica increased. The polymerization activities of metallocene supported on silica showed the similar trend after ionic liquid functionalization.

• Polymer Science and Technology
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• v.8 no.5
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• pp.566-572
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• 1997

• Bulletin of the Korean Chemical Society
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• v.16 no.1
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• pp.71-73
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• 1995

• Bulletin of the Korean Chemical Society
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• v.17 no.6
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• pp.558-560
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• 1996

• Bulletin of the Korean Chemical Society
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• v.14 no.3
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• pp.324-325
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• 1993

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.169-171
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• 1993

• Food Science and Biotechnology
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• v.17 no.2
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• pp.228-233
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• 2008

Considerable progress has been made in functionalization of the soy isoflavones through enzymatic modification of daidzin, genistin, and glycitin. After hydrolysis of $\beta$-glucosides into their corresponding aglycones, these compounds were structurally modified via biotransformations such as regioselective hydroxylation, enantioselective reduction, regioselective methylation, and polymerization. These reactions often resulted in an increase of the biological activities (e.g., anti oxidative activity, antiproliferative activity) and/or improvement of the physico-chemcial properties (e.g., water solubility, bioavailability). This review briefly summarizes on-going research activities on the biofunctionalization of the soy isoflavones.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.376-376
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• 2016

Poly(ethylene oxide) (PEO)/functionalized bacterial cellulose nanowhiskers (f-BCNW) (0.1 wt%) composite nanofibers were fabricated by electrospinning process and the thermomechanical properties were significantly enhanced more than the PEO and PEO/bacterial cellulose nanowhiskers (BCNW) (0.1 wt%) composite nanofibers. The functionalization of BCNW (f-BCNW) was performed by microwave plasma treatment for effects of nitrogen functionalization of chemically-driven BCNW. The N-containing functional groups of f-BCNW enhanced chemical bonding between the hydroxyl groups of the polymer chains in the PEO matrix and diameter size of PEO/f-BCNW (0.1 wt%) composite nanofibers were decreased more than PEO and PEO/BCNW (0.1 wt%) composite nanofibers on the same concentration. The strong interfacial interactions between the f-BCNW nanofillers and polymer matrix were improved the thermomechanical properties such as crystallization temperature, weight loss and glass transition temperature (Tg) compared to PEO and PEO/BCNW composites nanofibers. The results demonstrated that N2 plasma treatment of BCNW is very useful in improving thermal stability for bio-applications.

• Ceramist
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• v.21 no.3
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• pp.270-282
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• 2018

The increasing importance of biomedical imaging technology has led to the development of a variety of luminescent materials, including molecular fluorophores, fluorescent proteins, and quantum dots. Owing to their inherent disadvantages, such as insufficient chemical stability and limited biocompatability, their utilization has been limited with imaging only under highly optimized and controlled conditions. Recently, a new class of luminescent nanoparticles, upconversion nanoparticles (UCNPs), have been emerging as a practically useful nanoprobe for various bioimaging applications. The detailed synthesis, functionalization, properties and in-vitro / in-vivo applications of the UCNPs are introduced and discussed in this Review.

• Journal of Sensor Science and Technology
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• v.20 no.5
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• pp.289-293
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• 2011

Networked $SnO_2$ nanowires were uniformly functionalized with Pd nanoparticles via ${\gamma}$-ray radiolysis. The Networked $SnO_2$ nanowires were fabricated through a selective growth method. The sensing properties of the Pd-functionalized $SnO_2$ nanowires were analyzed in terms of their response to $NO_2$ and CO gases. The response time and sensitivity of the sensors were significantly improved for $NO_2$ at lower temperatures by the Pd functionalization. The enhancement in the sensing properties is likely to be due to the spillover effect of the Pd nanoparticles.