• Composites Research
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• v.34 no.6
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• pp.434-439
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• 2021

Graphene and polyaniline with thermoelectric properties are one of the potential substitutes for inorganic materials for flexible thermoelectric applications. In this study, we studied the photo-induced thermoelectric effect of graphene-polyaniline composites. The graphene-polyaniline composites were synthesized by introducing an amine functional group to graphene oxide for covalently connecting graphene and polyaniline, reducing the graphene oxide, and then polymerizing the graphene oxide with aniline. Graphene-polyaniline composites were prepared by changing the aniline contents in order to expect an optimal photothermoelectric effect, and their structural properties were confirmed through FT-IR and Raman analysis. The photocurrent and photovoltage characteristics were analyzed by irradiating light asymmetrically without an external bias and the current and voltage with various aniline contents. While the photocurrent trends to the electrical conductivity of the graphene-polyaniline composites, the photovoltage was related to the temperature change of the graphene-polyaniline composite, which was converted into thermal energy by light.

• Clean Technology
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• v.13 no.2
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• pp.143-150
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• 2007

The objective of this study is to develop hydrocarbon-based cleaning agents by blending paraffins, glycol ethers and siloxanes in oder to effectively clean contaminants such as flux, solder and grease. And the effect of cleaning ability by wetting index, aniline points and solubility parameter of the formulated hydrocarbon-based cleaning agents were studied in this work. The formulated hydrocarbon-based cleaning agents were prepared on the base of physical properties of their individual components. Wetting indexes and aniline points of their were measured through experiments and solubility parameters of their were calculated based on the Hansen's equation. In this study, evaluation of cleaning ability by cleaning agents were carried out using contaminants such as flux, solder, and grease. The experimental results showed that the cleaning ability of the formulated cleaning agents was excellent in cleaning contaminants such as flux, solder and grease and that the influencing parameters on their cleaning efficiency were found to be different according to contaminant types. MC($20.3MPa^{1/2}$), DF-1 ($24.2MPa^{1/2}$) and DF-2($21.5MPa^{1/2}$) with similar solubility parameter as flux ($21.3MPa^{1/2}$) showed 100% cleaning efficiency within 3 minutes in flux cleaning. And CFC-113, MC and 1,1,1-TCE with low aniline point less than $-20^{\circ}C$ showed excellent cleaning efficiency in solder cleaning. DG-1($16.2\;MPa^{1/2}$) and DG-2($15.5\;MPa^{1/2}$) with similar solubility parameter as grease($15.0{\sim}17.0\;MPa^{1/2}$) showed relatively low cleaning efficiency of grease, but CFC-113 and MC with high wetting index and low aniline point showed good cleaning efficiency in grease cleaning. As a result of this study, the hydrocarbon-based cleaning agents alternative to regulated cleaning agents such as CFC-113, 1,1,1-TCE and MC were able to be developed through properly blending paraffins, glycol ethers and siloxanes for cleaning flux, solder and grease. And it can be shown that various influencing parameters of cleaning efficiency such as wetting index, aniline point, solubility parameter and etc. of the non-aqueous cleaning agent should be reviewed for prediction of their cleaning ability and can be applied to formulation of cleaning agents.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.359-363
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• 1995

New ten N-[1-(benzotriazol-1-yl)alkyl]aniline(4) derivatives were synthesized and the crystal structure of 4h was shown by X-ray crystallography and the absolute configuration has been assigned as S form. The molecule crystallizes in the monoclinic system, space group $P2_{1}/n$. And the molecules in the crystal are linked with each other through the hydrogen bond $(N_{11}-H_{11}{\cdots}N3)$ with distance $2.300(11){\AA}$ The fungicidal activity($pI_{50}$) in-vitro against Botrytis cineria (BC), Phytophthora casici (PC) and Sclerotium cepinorum (SC) were determined by the agar dilution method. The structure activity ralationships (SAR) between structure of 4 and the activity were studied using a physicochemical parameters of substituents and multiple regression technique. Among these compounds, only the bromo group substituent(4f) showed higher activity, which depend on the hydrophobic(${\pi}$) of substituents. The relative orders of the activity are SC>BC> and PC, respectively. This implies that the activity is affected by the hydrophobic(${\pi}$) nature of the Z group rather than the X group. Linear free energy relationships(LFER) on the fungicidal activity with substituents has been also discussed.

• Geotechnical Engineering
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• v.9 no.3
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• pp.49-60
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• 1993

The compatibility of chemicals in the leachates with the three natural and artificially -made liner materials is analyzed by performing the laboratory hydraulic conductivity test. The selected liner materials are natural marine clay, fly ash and weathered granitic soil stomped from Kimpo Wastefills, Seochon power plant and Mansu Dong, Inchon, respectivaly. Bentonites of 20 and 10 percent by weight are used as additive materials for fly ash and weathered granitic soil and the chemical solutions used in the test are acetic acid, methanol, heptane, and aniline which are frequently found in the leachate of waste fills. The concentrations of the chemical solutions are 100% and 75%. The results of the tests show that hydraulic conductivities of the oxter materials are increased by one or two orders of magnitude with permeating pure chemical solutions. The rate of hydraulic conductivity increase is lowest for Seochon fly ash admixed liner and highest for natural marine clay liner. The influence of hydraulic chemical solutions on the liner materials is least for acetic acid and largest for aniline. The increases of conductivity are not shown with the permeation of the solution of concentration 75%. At least by this test results, it can be recognized that the tested liner material can be quite stable with the solutions of significantly high concentration except pure solutions.

• Journal of the Korean Chemical Society
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• v.35 no.5
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• pp.480-486
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• 1991

The solubilities of ethyl bromide in aniline and o-chloroaniline have been measured at 5, 15$^{\circ}$ and 25$^{\circ}$C in the presence and the absence of gallium bromide. When gallium bromide does not exist in the system, the solubility of ethyl bromide in o-chloroaniline is greater than in aniline, indicating a stronger interaction of ethyl bromide with o-chloroaniline than that with aniline. It could be thought that ethyl bromide forms unstable complex with gallium bromide in the presence of gallium bromide in the system. This complex has been assumed in various ways and evaluated, that instability constant (K value) is relatively constancy under the assumption of 1 : 1 complex, $C_2H_5Br{\cdot}GaBr_3$. Therefore, the complex forms the following equilibrium in the solution: $C_2H_5Br{\cdot}GaBr_3\;{\rightleftharpoons}\;C_2H_5Br +1/2Ga_2Br_6$ The instability of the complex of ethyl bromide with gallium bromide is compared with similar complexes of gallium bromide with methyl bromide. The changes of enthalpy, free energy and entropy fcor the dissociation of the complex are also calculated.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.119-124
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• 2018

The production of methyl N-phenyl carbamate by an oxidative carbonylation method of aniline and methanol is of great interest as an environmentally friendly process that can replace the monomer production process of a polymer produce using conventional phosgene. In this study, heterogeneous catalysts were prepared by using Y-zeolite, $SiO_2$, $Al_2O_3$ as support, and oxidative carbonylation continuous operation from aniline and methanol was attempted using the prepared heterogeneous catalyst. Batch reactor was used to determine the support, and various reaction conditions such as reaction temperature, reaction pressure, and effect of promoter were established using palladium catalyst. A reaction kinetics study was conducted under optimum reaction conditions. The basic data for carbamate process development were obtained by performing continuous operation for a long time under established reaction condition.

• Korean Journal of Food Science and Technology
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• v.32 no.5
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• pp.1179-1185
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• 2000

Fermented anchovy was used to investigate its effects on the formation of lipid peroxide and the activities of epoxide or free radical generating enzyme in vitro in bromobenzene-treated rats. All solvent fractions from fermented anchovy not only showed the strong antioxidative activities on linoleic acid autooxidation, but also reduced bromobenzene-induced hepatic lipid peroxidation. The activities of aniline hydroxylase and aminopyrine N-demethylase elevated by bromobenzene were recovered to the level of normal rats by adding the solvent fractions of fermented anchovy. But, xanthine oxidase and aldehyde oxidase activities were not affected by fermented anchovy. These results suggest that reduction of the bromobenzene-induced hepatic lipid peroxidation is caused by inhibition on the epoxide formation, not on free radical generation.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.407-416
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• 2019

The criticical micelle concentration (CMC) was measured by using the UV-Vis method for the micellization of the ammonium type cationic surfactants (DTAB, TTAB, and CTAB) in the aqueous aniline solution. The enthalpy change (${\Delta}H^0$) and entropy change (${\Delta}S^0$) were calculated from the dependence of Gibbs free energy change (${\Delta}G^0$) on the temperature for micellization of the cationic surfactants between 290K and 314K. The effects of n-butanol and sodium chloride on the micellization of cationic surfactants were measured and compared with the other thermodynamic functions. All the free energy changes (${\Delta}G^0$) of the micellization were negative, all the enthalpy change (${\Delta}H^0$) were negative, and all the entropy change (${\Delta}S^0$) were positive values, respectively. The micelle formation of cationic surfactant in aniline solution is a spontaneous exothermic reaction, and the iso-structural temperature calculated from the thermodynamic values show that enthalpy and entropy contribution to the micellization are almost the same for the micellization of cationic surfactants

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.190.2-190
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• 1996

No Abstract, See Full Text

• Journal of the Korean Society of Clothing and Textiles
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• v.23 no.4
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• pp.584-592
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• 1999

Highly conductive polyaniline(PAn)-nylon 6 composite fabric was prepared by immersing the nylon 6 fabric in 0.5M aniline+0.35M HCl aqueous solution at 4$0^{\circ}C$ for 2hours, Polymerization was then followed by mixing the prepared oxidant and dopant solution(0.5M(NH4)2S2O+0.35M HCl) to the diffusion bath at 5$^{\circ}C$ for 30 minutes. The conductivity of prepared PAn-nylon 6 composite fabrics reached as high as 0.5$\times$10-1S/cm. Their conductivity were significantly affected by the aniline and oxidant concentration. As compared to those of nylon 6 fabric heat of fusion melting point the degree of crystallinity and tensile strength of PAn-nylon 6 did not significantly changed by inclusion of PAn. In the aspect of serviceability wheras the fabric conductivity was significantly decreased after multiple washion no significant changes in the fabric conductivity were observed after abrading the composite fabric over 50 cycles. However we found that the fabric conductivity could be recovered by acid re-doping with HCl.