• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.3
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• pp.198-202
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• 2002

Ethanolamine (ETA), instead of ammonia, increases pH in the secondary system water and inhibits the corrosion of iron, which improves the integrity of the steam generator tubes. The different physicochemical properties of ETA from ammonia provide the different effect on the dissolution and adsorption of corrosion products entering the steam generator and thus on the hideout returns of ionic impurities in the steam generator sludge pile. The objective of this study was to investigate those properties with increasing temperature. ETA is more adsorbed onto the iron oxides, which increases the solubility of them and also lowers the hideout returns due to the reduced impurities adsorbed.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.933-940
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• 1992

Calix[6]arene react with formaldehyde and secondary amines to yields water soluble Mannich bases which can be converted to the corresponding quaternary salts. Treatment of the quaternary salts with a nucleophile such as cyano, ethoxy, and hydride yields p-substituted calix[6]arenes. Calix[8]arene too react with formaldehyde and diallyl amine to yield a water soluble Mannich base. The transport of neutral arenes through an aqueous phase along a concentration gradient mediated by those of water soluble calixarenes as molecular carrier was studied in a U-type cell. Naphthalene, anthracene, pyrene, and fluoranthene are tested as a neutral solid guest compounds for the transport experiment.

• Elastomers and Composites
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• v.43 no.1
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• pp.31-38
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• 2008

Sonochemical reaction of fullerene oxides, $[C_{70}(O)_n](n\geq1)$ with several aromatic amines such as 4-nitroaniline, 3-nitroaniline, and 4-isopropylaniline, in the presence of $FeCl_3$ were investigated under ultrasonic irradiation. This method is applicable to a wide variety of aromatic amines especially ring deactivated, to afford the corresponding cleavage products under mild conditions. The aminated fullerenes were confirmed by MALDI-TOF-MS and UV-vis spectra.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.579-585
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• 2017

Acrylic resins containing tertiary amine were synthesized by a radical polymerization of monomers including n-butyl acrylate (BA), methyl methacrylate (MMA), n-butyl methacrylate (BMA) and dimethylaminoethyl methacrylate (DMAEMA), and diethylaminoethyl methacrylate (DEAEMA) containing tertiary amine. Synthesized acrylic resins were applied to develope coatings of acrylic resins containing tertiary amine. And ${\gamma}$-glycidoxypropyl trimethoxysilane (GPTMS) or ${\gamma}$-glycidoxypropyl triethoxysilane (GPTES) was used as hardener. Developed coatings were white colored ones to use titanium dioxide and were hardened with hardener for measuring their physical properties. Measured physical properties were basic properties, adhesivity and weatherability. As a result, developed acrylic resins coatings containing tertiary amine showed excellent adhesivity on various substrates and also showed the same result on weatherability on dry weather condition.

• Journal of the Korean Chemical Society
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• v.47 no.5
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• pp.466-471
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• 2003

The effect of polyamines on the cabbage phospholipase D(PLD) activity was investigated. The PLD activity was determined by pH-stat titration of phosphatidic acid, one of the enzymatic reaction product, using phosphatidyl choline small unilamellar vesicles as a substrate. The cabbage PLD was activated approximately 4 fold by spermine at 1 mM concentration. This spermine effect appears to be similar to the previous report on the PLD activation of rat brain mitochondrial fraction. It was also found that cationic polypetides such as polylysine and polyhistidine exerted a marked enhancement effect on the cabbage PLD. Particularly polyhistidine exerted approximately 5.5 fold enhancement effect at 0.062 mM concentration. The polyamine effect on the cabbage PLD was reexamined in the phosphatidylcholine/sodium dodecyl sulfate mixed micellar system. The relevance of polyamine effect on PLD activity is discussed in relation to the active site of PLD.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.411-414
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• 1990

Antithiamin activities of BHA, BHT PG and TBHQ of synthetic phenolic antioxidants at various pH's and temperatures were studied. All antioxidants had little antithiamin activity as is the case with control group at pH 4 and $38^{\circ}C$, but antithiamin activity was stronger at $60^{\circ}C$ than at $38^{\circ}C$ under the same pH. Meanwhile, the destruction of thiamin incubated at $38^{\circ}C$ was more rapid at pH 7 than at pH 4, and the destruction of thiamin at pH 7 was much more rapid at $60^{\circ}C$ than at $38^{\circ}C$. BHA and BHT had little, or extremely slight antithiamin activity. Antithiamin activity of PG was comparatively strong, but TBHQ had the strongest antithiamin activity among synthetic phenolic antioxidants examined.

• Polymer(Korea)
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• v.27 no.2
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• pp.135-141
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• 2003

A series of organophilic montmorillonites (MMTs) modified with various alkyl siloxane amino oligomer groups have been synthesized and their properties were investigated. New organophilic MMTs containing siloxane amino oligomers with alkyl group instead of conventional alkyl amines were synthesized to improve thermal stability as well as gallery spacing. The organophilic MMTs were synthesized from MMT by utilizing the siloxane amino oligomers with various alkyl groups in the water/dioxane solution, which was performed without aq. HCl. Thermal decomposition temperature, gallery spacing, and hydrophobicity of synthesized organophilic MMTs were investigated. X-ray diffraction and TEM experiment results on new organophilic MMTs demonstrated that introduction of siloxane amine oligomers increased d-spacing between silicate layers. The decomposition temperatures of new organophilic MMTs measured by TGA was remarkably improved above 200℃ as compared with those of conventional alkyl substituted organophilic MMTs.

• Composites Research
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• v.17 no.6
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• pp.44-51
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• 2004

To determine the effect of numbers of nitrogen atom bonded at ethyl group included in main chain of linear amine curing agents of epoxy-cure systems on the thermal and mechanical properties, standard epoxy resin DGEBF was cured with DETA, TETA and TEPA in a stoichiometrically equivalent ratio. From this work, the effect of curing agents of the DGEBF/amine systems oil the thermal and mechanical properties was significantly influenced by numbers of nitrogen atom of curing agents. The results showed that heat of reaction increased, and maximum exothermic temperature decreased with the decrease of numbers of nitrogen atom. In case of cured systems, density and maximum conversion(%) had no relation to numbers of nitrogen atom, but flexural modulus and tensile modulus increased with the decrease of numbers of nitrogen atom in main chain. Thermal stability, shrinkage(%), Tg, tensile and flexural strength showed irregular tendency having nothing to do with numbers of nitrogem atom at a sight. This findings imply that the differences in the maximum conversion(%) about the chain length of curing agents affect the thermal and mechanical properties.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.57-62
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• 2014

With synthesis temperature and adding amount of oleylamine, nanometer-sized Cu particles were fabricated by heptyl alcohol-based chemical synthesis. The synthetic temperature and amount of oleylamine changed excessively the shape and phase of synthesized nanoparticles. Only cubic-shaped $Cu_2O$ phase was formed at $160^{\circ}C$ regardless of the amount of oleylamine because of imperfect reduction reaction, representing results that the average size of $Cu_2O$ particles decreased with increasing the amount of oleylamine. In the case the synthesis at $170^{\circ}C$, however, nanoparticles of irregular sphere or peanut shapes were synthesized. Moreover, the average size of nanoparticles decreased continuously and gradually with an increase of the amount of oleylamine. According to the size decrease, the synthesized $Cu_2O$ nanoparticles were also transformed into pure Cu nanoparticles.

• Composites Research
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• v.28 no.5
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• pp.265-269
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• 2015

Development of simple and efficient method for large-scale production of mechanically strong and electrically conductive graphene fiber is highly desirable for practical applications, such as fiber-reinforced composites, wearable electronics, and electromagnetic irradiation shielding. Here, we present a facile approach for the preparation of amine-functionalized graphene fibers by simple wet-spinning of diamine-functionalized graphene oxide (GO-$NH_2$), which is used because of its synthetic convenience, good dispersity, and scalable production with low cost. The amine-functionalized graphene fiber shows high electrical and mechanical properties compared to pristine graphene oxide fiber due to the electrostatic interaction between amine groups and electronegative functional groups of graphene oxide.