• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.200-200
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• 2006

Several polynorbornene or poly(norbornene-7-oxide) based functional block copolymers were synthesized by ring opening metathesis polymerization (ROMP) with good molecular weight and polydispersity control. Some representative functional groups in these polymers are a nitrobenzoyl group or ferrocene. These polymers were subjected to various chemical modification reactions to give other block copolymers that contain novel functionality such as amine, diazonium salt, and diazo groups. The resulting polymers were characterized by various techniques such as GPC, NMR, UV-VIS, AFM, and cyclovotammography (CV).

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제1회 추계심포지움 and 제2회 생리분자과학연구센터워크숍
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• pp.36-38
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• 1993

내피세포 (endothelial cells, EC)는 amine, peptide, 단백, arachidonic acid 및 그 대사물 등의 여러 화학물질에 의하여 내피세포 의전성 이완물질 endothelium-derived relaxing factor, EDRF)을 유리할 뿐만 아니라 맥압(脈壓)과 같은 물리적 변동에 의하여서도 EDRF가 유리된다. EDRF는 처음에 Furchgott와 Zawadzki (1980)에 의하여 보고되었고, EDRF의 실질적인 성분이 무엇인가에 대하여는 그동안 많이 검토되어 왔다(Marshall 와 Kontos, Hong 등, 1990).Ignarro 등 (1987)과 Palmer등 (1987)은 EDRF에 의한 생물학적 반응이 NO (nitric oxide)와 유사하거나 같은 물질이라고 보고하였고,Furchgott 등 (1986)과 Ignarro등 (1988)도 EDRF가 NO와 유사하거나 같은 물질일 것이라고 단정하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2006년도 추계학술발표대회 및 제11회 신소재 심포지엄
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• pp.15.1-15.1
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• 2006

• Macromolecular Research
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• 제17권12호
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• pp.995-1002
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• 2009

Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

• Carbon letters
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• 제13권1호
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• pp.29-33
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• 2012

A novel strategy for the simultaneous reduction and functionalization of graphene oxide (G-O) was developed using polyallylamine hydrochloride (PAAH) as a multi-functional agent. The G-O functionalization by PAAH was carried out under basic conditions to catalyze the epoxide ring opening reaction of G-O with abundant amine groups of PAAH. We found that G-O was not only functionalized with PAAH but also reduced under the reaction condition. Moreover, the synthesized PAAH-functionalized G-O sheets were soluble in water and applicable to the synthesis of nanocomposites with gold nanoparticles.

• Advances in nano research
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• 제6권4호
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• pp.357-375
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• 2018

Two dimensional (2D) atomic layered nanomaterials exhibit some of the most striking phenomena in modern materials research and hold promise for a wide range of applications including energy and biomedical technologies. Graphene has received much attention for having extremely high surface area to mass ratio and excellent electric conductivity. Graphene has also been shown to maximize the activity of surface-assembled metal nanoparticle catalysts due to its unique characteristics of enhancing mass transport of reactants to catalysts. This paper specifically investigates the strategy of pre-formed nanoparticle self-assembly used for the formation of various metal nanoparticles supported on graphene families such as graphene, graphene oxide, and reduced graphene oxide and aims at understanding the interactions between ligand-capped metal nanoparticles and 2D nanomaterials. By varying the functional groups on the ligands between alkyl, aromatic, amine, and alcohol groups, different interactions such as van der Waals, ${\pi}-{\pi}$ stacking, dipole-dipole, and hydrogen bonding are formed as the 2D hybrids produced.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.243.1-243.1
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• 2011

We demonstrate a facile and robust layer-by-layer (LbL) assembly method for the fabrication of nonvolatile resistive switching memory (NRSM) devices based on superparamagnetic nanocomposite multilayers, which allows the highly enhanced magnetic and resistive switching memory properties as well as the dense and homogeneous adsorption of nanoparticles, via nucleophilic substitution reaction (NSR) in nonpolar solvent. Superparamagnetic iron oxide nanoparticles (MP) of about size 12 nm (or 7 nm) synthesized with oleic acid (OA) in nonpolar solvent could be converted into 2-bromo-2-methylpropionic acid (BMPA)-stabilized iron oxide nanoparticles (BMPA-MP) by stabilizer exchange without change of solvent polarity. In addition, bromo groups of BMPA-MP could be connected with highly branched amine groups of poly (amidoamine) dendrimer (PAMA) in ethanol by NSR of between bromo and amine groups. Based on these results, nanocomposite multilayers using LbL assembly could be fabricated in nonpolar solvent by NSR of between BMPA-MP and PAMA without any additional phase transfer of MP for conventional LbL assembly. These resulting superparamagnetic multilayers displayed highly improved magnetic and resistive switching memory properties in comparison with those of multilayers based on water-dispersible MP. Furthermore, NRSM devices, which were fabricated by LbL assembly method under atmospheric conditions, exhibited the outstanding performances such as long-term stability, fast switching speed and high ON/OFF ratio comparable to that of conventional inorganic NRSM devices produced by vacuum deposition.

• 한국수산과학회지
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• 제21권3호
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• pp.169-176
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• 1988

In order to obtain the objective indices which can assess the quality and the shelf-life of dried squid, nonenzymatic browning, carbonyl value, trimethyl amine (TMA) and trimethyl amine oxide (TMAO) decrease and panel test were determined in dried squid at various water activity levels. When the data of nonenzymatic browning fit a zero order equation, $r^2$ value were more than 0.92 except aw 0.52 for 0.8241. Through variance analysis for the data of browning extent and TMAO decrease, the confidence limits of regression equation were $99\%$ and their limit values of shelf-life were shown 0.45390 O. D./g. solid and 190.322 g/g respectively. In case of TMAO, $r^2$ value was calculated more than 0.95. Linear regression equation for the correlation between browning data and average panel score was Y=0.6138-0.053X and its $r^2$ value was 0.9285. Also in TMAO decrease, the equation was InY=2.0314+0.08269x and $r^2$ value was 0.7854. The shelf-life, evaluated by nonenzymatic browning, TMAO decrease and panel test, was 110-170 days at aw 0.45-0.76 except aw 0.15.

• BMB Reports
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• 제54권11호
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• pp.557-562
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• 2021

Microglial activation is closely associated with neuroinflammatory pathologies. The nucleotide-binding and oligomerization domain-like receptor containing a pyrin domain 3 (NLRP3) inflammasomes are highly organized intracellular sensors of neuronal alarm signaling. NLRP3 inflammasomes activate nuclear factor kappa-B (NF-κB) and reactive oxygen species (ROS), which induce inflammatory responses. Moreover, NLRP3 dysfunction is a common feature of chronic inflammatory diseases. The present study investigated the effect of a novel thiazol derivative, N-cyclooctyl-5-methylthiazol-2-amine hydrobromide (KHG26700), on inflammatory responses in lipopolysaccharide (LPS)-treated BV-2 microglial cells. KHG26700 significantly attenuated the expression of several pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6, in these cells, as well as the LPS-induced increases in NLRP3, NF-κB, and phospho-IkBα levels. KHG26700 also suppressed the LPS-induced increases in protein levels of autophagy protein 5 (ATG5), microtubule-associated protein 1 light chain 3 (LC3), and beclin-1, as well as downregulating the LPS-enhanced levels of ROS, lipid peroxidation, and nitric oxide. These results suggest that the anti-inflammatory effects of KHG26700 may be due, at least in part, to the regulation of the NLRP3-mediated signaling pathway during microglial activation.

• Composites Research
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• 제29권4호
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• pp.132-137
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• 2016

Based on mussel-inspired polydopamine (PDA), a novel technique to fabricate carbon nanowire (CNW) arrays is presented for a possible use of porous carbon electrode in electrochemical energy storage applications. PDA can give more porosity and nitrogen-doping effect to carbon electrodes, since it has high graphitic carbon yield characteristic and rich amine functionalities. Using such outstanding properties, the applicability of PDA for electrochemical energy storage devices was investigated. To achieve this, the decoration of the CNW arrays on carbon fiber surface was performed to increase the surface area for storage of electrical charge and the chemical active sites. Here, zinc oxide (ZnO) nanowire (NW) arrays were hydrothermally grown on the carbon fiber surface and then, PDA was coated on ZnO NWs. Finally, high temperature annealing was performed to carbonize PDA coating layers. For higher energy density, manganese oxide ($MnO_x$) nanoparticles (NPs), were deposited on the carbonized PDA NW arrays. The enlarged surface area induced by carbon nanowire arrays led to a 4.7-fold enhancement in areal capacitance compared to that of bare carbon fibers. The capacitance of nanowire-decorated electrodes reached up to $105.7mF/cm^2$, which is 59 times higher than that of pristine carbon fibers.