• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.48-55
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• 2011

It was found that the absorbent mixed with 2-aminoethanol and others has been applied to remove them via chemical neutralization. The absorbent of natural second metabolites was achieved by a removal efficiency of 20~30% by itself depending on treatment conditions, but the complex absorbent mixed with 0.2% amine chemical provides the removal efficiency of over 98%. Optimal removal efficiencies have been examined against two major parameters of the temperature and pH to remove ammonia and hydrogen sulfide gases. The chemical analysis was also performed to analyze the composition of an essential oil by GC-MS. The monoterpenes in an essential oil reacted with odorous compounds by neutralization and their reaction mechanism was partially elucidated.

• Journal of the Korean Vacuum Society
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• v.4 no.S2
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• pp.1-7
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• 1995

Cu(400$\AA$)/Polyimide has been mixed with 80 keV Ar+ and N2+from 1.0X1015ions/$\textrm{cm}^2$ to 2.0X1016 ions/$\textrm{cm}^2$. The changes of chemical bond and internal properties of sample are investigated by X-ray photoelectron spectroscopy(XPS). The quantitative adhesion strength is measured by using scratch test. The optimized mixing condition is that Cu/PI is irradiated with 80 keV N2+ at a dose of 1.0X1015 ions/$\textrm{cm}^2$, because N2+ ions can product more pyridine-like moiety, amide group, and tertiary amine moiety which are known as adesion promoters than Ar+.

• Corrosion Science and Technology
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• v.14 no.1
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• pp.25-32
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• 2015

The alloy content of structural materials of nuclear power plants has been recognized an important factor in predicting flow accelerated corrosion (FAC). In particular, many literature data reported that chromium content is one of the most important alloying element and even a small amount of chromium is effective to suppress FAC. This report reviewed and compared chromium models of Ducreux, Bouchacourt, and Kastner which were used in predicting FAC rates. The plant data indicate that Ducreux model may be conservative for the specimen containing 0.15 wt% chromium. The related articles were reviewed as follows. Combined effects of chromium content, pH, temperature, dissolved oxygen (DO), flow velocity, test time, and kinds of amine on the FAC rate were described. 0.1 wt% chromium in steel did not affect the FAC rate with changes in pH. The FAC rates pronounced with higher flow rate and increased with increasing test duration(600 d) for 0.013 wt% chromium. The FAC rates in mixed amine chemistry were higher than in ammonia chemistry, which may be lessened by the addition of chromium to the steel.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04c
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• pp.75-79
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• 2008

In this paper, we measured the activation energy of the Bisphenol A type Epoxy resin (DGEBA)-Jeffamine system according to an irradiation. We put the mixed solutions to the silicon mold after mixing both DGEBA(216g) and Jeffamine(93.9g), curing agent of amine system. The mixed solutions were cured in the atmosphere during 24hours after finishing the first curing during 4hours in the vacuum oven under $80^{\circ}C$. The mixed solutions were cured in the atmosphere during 24hours after finishing the second curing during 12hours in the vacuum oven under $60^{\circ}C$ again. Prepared samples were irradiated to the dose rate of 8kGy/hr with 500kGy, 700kGy, 1000kGy, 1500kGy, 2000kGy, 2500kGy. Experimental results indicated activation energy of the samples reduced as the irradiation dose increased because of the peroxides of the Epoxy created by the oxidation and the radiation.

• Elastomers and Composites
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• v.50 no.4
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• pp.265-273
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• 2015

In this work, the emulsified asphalt with high phase stability and storage stability was prepared by using phase inversion emulsification and the surfactant mixed with cationic and nonionic surfactants. It was found that the asphalt together with Span 20, nonionic surfactant and DDA (Dimethyl Dodecyl Amine), cationic surfactant showed the most stable phase. The phase stability of the emulsified asphalt, therefore, was investigated through the particle size with mixed surfactant content, rheology behavior and Zeta potential value; the particle size decreased with the increase of the mixed surfactant content but the viscosity increased. The shear thinning behaviors and the Zeta potential value with 50 mV~60 mV were shown, which was found to be considered stable. In addition, SBR latex(Styrene-butadiene-rubber) and water dispersed Epoxy (EPD) were used to enhance the physical properties of the emulsified asphalt. The swelling and adhesion features of the emulsified asphalt were also studied with $CaCO_3$, Silica, and Montmorillonite (MMT). It was shown that the addition of SBR latex and MMT can be another way to improve the physical properties of the emulsified asphalt in that the lowest swelling feature was found.

• Applied Chemistry for Engineering
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• v.33 no.2
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• pp.179-187
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• 2022

In this study, the synthesis of 1,2-dodecylaminopropanediol (1,2-DDAP) having a 12 carbon chain length and an amine group was designed to improve the preservation and hydrophilicity of 1,2-alkanediol-based compounds. 1,2-DDAP was prepared by reacting dodecylamine (DDA) with 3-monochloro-1,2-propanediol (3-MCPD) in an ethanol solvent at 40 ℃, and its yield and purity were about 56% and 98%, respectively, under a reaction condition of 2 h and a DDA:3-MCPD molar ratio of 1:0.8. The antimicrobial effect of 1,2-DDAP showed the values of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against microorganisms at concentrations of 10 to 100 times lower than those of 1,2-octanediol(1,2-ODIOL) or 1,2-decanediol (1,2-DDIOL). Based on the hydrophilic properties of 1,2-DDAP, mixed preservatives were prepared by adding small amounts of 1,2-ODIOL or 1,2-DDIOL, which are poorly soluble in water, with 1,2-DDAP. Mixed preservatives exhibited an effect of inhibiting microorganisms equal to or greater than that of 1,2-DDAP alone in antimicrobial activity tests. As a result of confirming the preservation effect in lotion (cosmetic formulation) for application, 1,2-DDAP showed similar antimicrobial activity at concentrations of 0.3 to 0.6 times lower than that of 1,2-ODIOL or 1,2-DDIOL. Therefore, it is considered that the use of 1,2-DDAP alone and the mixed use with small amounts of 1,2-ODIOL or 1,2-DDIOL can be a good alternative to preservatives in the product.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.26-32
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• 2003

For the purpose of manufacturing water-resistant corrugated board boxes for agricultural products in the cold chain system, the effects of fiber types, wet strength agents and a moisture-proof chemical on the properties of the base papers were investigated first. PAE(polyamide amine epichlorohydrin) showed better performance than MF(melamine formalde-hyde) over broad stock pH ranges, which was prefered as wet strength agent for the paper grade. When short fibers(AOCC, KOCC) were mixed with long fiber(UKP) in certain ratios, some physical properties of the paper made with mixed fibers were similar to those of the paper made with UKP only. Paper containing AOCC showed the biggest increase in water resistance when PAE was added to the stock. Synergistic effects in moisture-proof and some mechanical properties of paper were appeared when PAR was added internally, together with the coating of a moisture proof chemical on the sheets.

• YAKHAK HOEJI
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• v.55 no.3
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• pp.251-259
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• 2011

Cigarette smoke condensate (CSC) is known to be carcinogenic compound. CSC contains many organic compounds such as polycyclic aromatic hydrocarbons (PAHs), and heterocyclic amine compounds (HCAs). Reactive oxygen species (ROS) are also generated and induce oxidative DNA damage during the metabolism of CSC. The rat microsome mediated and DNA repair enzyme treated comet assays together with conventional comet assay were performed to evaluate the mechanisms of CSC genotoxicity. The organic extract of CSC induced oxidative and microsome mediated DNA damage. Vitamin C as a model antioxidant reduced DNA damage in endonuclease III treated comet assay. One of flavonoid, galangin as a CYP1A1 inhibitor, reduced DNA damage in the presence of S-9 mixture. The ethanol extracts of the mixed vegetables (BV) or the mixed fruits (BF) showed potent inhibitory effects against CSC induced DNA damage with oxidative DNA lesions and in the prescence of S-9 mixture. These results indicate that BV and BF could prevent CSC-induced cellular DNA damage by inhibiting oxidative stress and suppressing cytochrome P450 in mammalian cells.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.61-67
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• 1995

PVC membrane electrodes based on the lipophilic neutral carrier, dibenzo-18-crown-6, cyclic oligomers of teit-butylphenol-formaidehyde condensates, calix[4]arenes as the active sensors for verapamil have been prepared and tested in a variety of plasticizers. At pH 5.0, the electrode exhibits a Nernstian response in the range of 10$^{-2}$~5$\times$10$^{-5}$ M verapamil with a slope of 49.1$\pm$0.5mV per concentration decade. The electrode constructed in this work can be used continuously for at least 1 month before any damage to the membrane occurs. And the analyses of the local anesthetic amine, which are good to select a specific compound in a mixed solution, were also accomplished by using of another neutral carrier, a DB18C6, for comparing with calix[4]arene.

• The Journal of Advanced Prosthodontics
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• v.7 no.5
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• pp.386-391
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• 2015

PURPOSE. The purpose of this preliminary study was to investigate the effects of adding 4,4'-bis(N,N-diethylamino) benzophenone (DEABP) as a co-initiator to a binary photoinitiating system (camphorquinone-amine) to analyze on the degree of conversion (DC) of a light-cured resin for dental 3D printing. MATERIALS AND METHODS. Cylindrical specimens (N=60, n=30 per group, ${\phi}5mm{\times}1mm$) were fabricated using bisphenol A glycerolate dimethacrylate (BisGMA) both with and without DEABP. The freshly mixed resins were exposed to light in a custom-made closed chamber with nine light-emitting diode lamps (wavelength: 405 nm; power: $840mW/cm^2$) for polymerization at each incidence of light-irradiation at 10, 30, 60, 180, and 300 seconds, while five specimens at a time were evaluated at each given irradiation point. Fourier-transform infrared (FTIR) spectroscopy was used to measure the DC values of the resins. Two-way analysis of variance and the Duncan post hoc test were used to analyze statistically significant differences between the groups and given times (${\alpha}$=.05). RESULTS. In the DEABP-containing resin, the DC values were significantly higher at all points in time (P<.001), and also the initial polymerization velocity was faster than in the DEABP-free resin. CONCLUSION. The addition of DEABP significantly enhanced the DC values and, thus, could potentially become an efficient photoinitiator when combined with a camphorquinone-amine system and may be utilized as a more advanced photopolymerization system for dental 3D printing.