• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.659-660
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• 2002

• Bulletin of the Korean Chemical Society
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• v.32 no.11
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• pp.4092-4094
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• 2011

• Textile Coloration and Finishing
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• v.5 no.3
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• pp.188-193
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• 1993

Aqueous polyurethanes(APU) were prepared from polypropylene glycol(PPG), dimethylol propionic acid(DMPA), and isophoron diisocyanate(IPDI) following a prepolymer mixing process. APUs were applied as binder for nonwoven fabrics processing. APU treated nonwoven fabrics generally showed better tear and tensile strength as compared with the untreated ones. In addition, depending on the soft segment length and crosslinking density of the PU, tear strength of APU treated fabrics was favorably compared with solvent type treated one. Similar results were obtained with microfiber nonwoven fabrics, however, the effect was less significant.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4191-4194
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• 2011

Sodium periodate ($NaIO_4$) and potassium iodide (KI) in aqueous ammonia has been used for the one-pot synthesis of nitriles from the corresponding aldehydes and alcohols in moderate to good yield. This transformation, proceeds via an in situ oxidation- imination-aldimine oxidation sequence.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.176.1-176.1
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• 2003

The protective effects on hepatic fibrosis of an aqueous extract from the roots of Platycodon grandiflorum A. DC (Campanulaceae), Changkil (CK), in hepatic stellate cell line, CFSC-2G. The increased deposition of extracellular matrix by hepatic stellate cells following liver injury in a process known as activation is considered a key mechanism for increased collagen content of liver during the development of liver fibrosis. (omitted)

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.10.2-10.2
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• 2011

The design and synthesis of protein-like polymers is a fundamental challenge in materials science. A biomimetic approach is to explore the impact of monomer sequence on non-natural polymer structure and function. We present the aqueous self-assembly of two peptoid polymers into extremely thin two-dimensional (2D) crystalline sheets directed by periodic amphiphilicity, electrostatic recognition and aromatic interactions. Peptoids are sequence-specific, oligo-N-substituted glycine polymers designed to mimic the structure and functionality of proteins. Mixing a 1:1 ratio of two oppositely charged peptoid 36 mers of a specific sequence in aqueous solution results in the formation of giant, free-floating sheets with only 2.7 nm thickness. Direct visualization of aligned individual peptoid chains in the sheet structure was achieved using aberration-corrected transmission electron microscopy. Specific binding of a protein to ligand-functionalized sheets was also demonstrated. The synthetic flexibility and biocompatibility of peptoids provide a flexible and robust platform for integrating functionality into defined 2D nanostructures. In the later part of my talk, we describe the use of metal ions to construct two-dimensional hybrid films that have the ability to self-heal. Incubation of biomimetic peptoid polymers with specific divalent metal ions results in the spontaneous formation of uniform multilayers at the air-water interface. We anticipate that ease of synthesis and transfer of these two-dimensional materials may have many potential applications in catalysis, gas storage and sensing, optics, nanomaterial synthesis, and environmentally responsive scaffolds.

• The Korean Journal of Ceramics
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• v.5 no.3
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• pp.250-254
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• 1999

Synthesis of the spinel $LiMn_2O_4$ by emulsion method was investigated. $LiOH.H_2O \;and \;Mn(NO_3)_2.6H_2O$ were used as starting materials to prepare mixed aqueous solution (0.5 mol/$\ell$ for the $LiMn_2O_4$). Kerosene, paraffin oil and span 80 were used for organic phase. The aqueous solutioin and organic phase were mixed in the ratio of 2:1 and emulsified at the speed of 4000 rpm for 5 min. The prepared emulsions were dropped into the petroleum heated at $170^{\circ}C$ to evaporate water in the silicon oil bath, dried at $120^{\circ}C$ in the oven the remove petroleum and calcined at temperature ranges from 600 to $900^{\circ}C$ for 48 hrs. The characteristics of powders were investigated by XRD, SEM, BET and electrochemical properties of synthesized cathode materials were measured with Galvanostatic system. $Li_{1.05}Mn_2O_4$ calcined at $800^{\circ}C$ for 48 hrs showed initial discharge capacity of 125.9mAH/g.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.141-144
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• 2011

We report the synthesis of $SrTiO_3$, $BaTiO_3$ and $Ba_xSr_{1-x}TiO_3$ (BST) nanoparticles (NPs) in various compositions (x = 0.25, 0.5 and 0.75) by an inorganic sol-gel method under a basic condition. Highly crystalline nanoparticles were formed at the reaction temperature of 25 - $100^{\circ}C$ from a stabilized titanium alkoxide in tetramethylammonium hydroxide (TMAH) and barium or strontium acetate in aqueous solution. Morphology and particle structure of the synthesized BST NPs were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The BST nanoparticles in various compositions were monodispersed without mutual aggregation, and their average sizes were in the range of 70 - 80 nm. Furthermore, they showed highly crystallized perovskite phase over the whole composition range from $SrTiO_3$ to $BaTiO_3$. We also proposed a mechanism for the low-temperature formation of BST NPs.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2256-2260
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• 2013

A new quinoline-based acylhydrazone (1) has been synthesized and applied as a fluorescent probe. Probe 1 exhibits high selectivity and sensitivity to $Cu^{2+}$ with fluorescence "ON-OFF" behavior in HEPES buffered (1‰ DMSO, HEPES 20 mM, pH = 7.4) solution. The on-site generated 1-$Cu^{2+}$ complex displays excellent selectivity to sulfide ions with fluorescence "OFF-ON" performance through copper displacement approach.

• Advances in Traditional Medicine
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• v.7 no.5
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• pp.540-548
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• 2008

Paeonia radix is the root of Paeonia aliflora Pallas, which is a perennial plant classified in the family Paeoniaceae. Paeonia radix possesses several pharmacological effects such as analgesic, anti-inflammatory and anti-allergic, anti-oxidative, and anti-coagulant activities. In this study, we investigated the effect of the aqueous extract of Paeonia radix on the lipopolysaccharide-induced inflammation in mouse BV2 microglial cells. The aqueous extract of Paeonia radix at respective concentration was treated one hour before lipopolysaccharide treatment. In the present results, the aqueous extract of Paeonia radix suppressed prostaglandin $E_2$ synthesis and nitric oxide production by inhibiting the lipopolysaccharide-stimulated mRNA expressions of cyclooxygenase-2 and inducible nitric oxide synthase in mouse BV2 microglial cells. These results demonstrate that Paeonia radix exerts anti-inflammatory and analgesic effects probably by suppressing mRNA expressions of cyclooxygenase-2 and inducible nitric oxide synthesis. The present study demonstrates that Paeonia radix may offer a valuable mean of therapy for brain inflammatory diseases.