• Corrosion Science and Technology
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• v.15 no.2
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• pp.78-83
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• 2016

The e-coating to inhibit induced corrosion can deposit a coating not only on the exterior surface but also on the inside of whole metallic components of body-in-white (BIW). But it is difficult to deposit paint films on the inside area because metallic components are multi layered. It may cause shortness of e-coating thickness. The only way to properly verify e-coating thickness is by performing the use of tear-down prototypes. When paint films' thickness is inadequate, a structural modification on each metallic component is needed. Verification of the thickness improvement for a structural modification requires much manual effort and leads to increasing development time. Recently, the simulation technology has been developed to predict the e-coating thickness in e-coating field. By applying the simulation to BIW, improvement in paint thickness quality and shortening of development period are expected. The paper explains a validated solution that allows simulating the effect of design changes to the e-coating thickness and current density, thereby delivering results within a time frame of a few days.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.12
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• pp.867-874
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• 2012

In the present study, three-dimensional transient numerical simulations were carried out to improve the performance of a vehicle paint drying process. In order to describe the movement of a vehicle, the techniques of moving boundary condition and multiple reference flames (MRF) were used. For the validation of the numerical analysis, the predicted temperature on the surface of a vehicle was compared to the experimental data, and a good agreement was achieved. With validated numerical procedure, various operating conditions of the temperature and the flow rate of the supply air were investigated to improve the drying performance of the facility. It is shown that the optimization of the operating condition can lead to energy savings and faster line speed of the production.

• Journal of Surface Science and Engineering
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• v.29 no.5
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• pp.563-569
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• 1996

Degradation of $Zn_3N_2$ films is studied by using several analytical techniques. Polycrystalline $Zn_3N_2$ films prepared by reactie rf magnetron sputtering are kept in the air. Electrical and optical properties are measured by using van der Pauw technique and double-beam spectrometry. Structure and chemical bonding states are studied by X-ray diffraction(XRD), Fourier transfer infrared ray spectroscopy(FT-IR) and X-ray photoelectron specroscopy (XPS). Significant differences are observed in optical properties between the degraded film and the ZnO film. XRD analysis reveals that the degraded film contains very small ZnO grains because very weak and broad ZnO peaks are observed. XPS and FT-IR measurements reveal the formation of $Zn(OH)_2$ in the degraded film. The existence of N-H bonds in degraded films is exhibited from the N 1s spectra. $Zn_3N_2$ change into the mixture of ZnO, $Zn(OH)_2$ and an ammonium salt.

• Natural Product Sciences
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• v.4 no.3
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• pp.161-169
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• 1998

The analogues of lichen components showing anti-tyrosinase activities were synthesized. 4-Alkylresorcinol derivatives showed both the inhibitory activity and cytotoxicity in B-16 melanoma cells at the doses of 10 mM to 1.2 mM. Resorcinol and 4-methylresorcinol showed the inhibitory effect with a low cytotoxicity at the doses of 2.5 mM and $600\;{\mu}M$ among 4-alkylresorcinols, respectively. Some diphenylmethane derivatives (Type A, B, and C) had strong activities with a low cytotoxicity. While xanthine derivatives had no effect. Glucosides of 4,5-alkylresorcinol and the diphenylmethane derivative (Type B) were prepared to decrease the cytotoxicity. As a result, no effect were observed. Liposome of the diphenylmethane derivative (Type B) was prepared for the same purpose, and the latter showed a remarkable effect at the dose of $15\;{\mu}M$ with a low cytotoxicity.

• Resources Recycling
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• v.9 no.6
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• pp.9-14
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• 2000

Comparing the adsorption characteristics of coconut shell activated carbon (CSAC) and waste paint activated carbon (WPAC), Freundlich adsorption isotherms of alkylbenzene sulfonate (ABS) obtained from the secondary treatment water of H company and effluent of D company were estimated q=23.12 $C^{0.42}$ , q=18.32 $C^{0.38}$ with WPAC and $q=36.76C^{1.37}$ /, q=26.67 $C^{0.42}$ with CSAC respectively. In the case of H company, breakthrough time of the ABS using CSAC by continuous experiment was estimated 680 minute md that of WPAC was 610 minute. In the case of D company effluent, CSAC was estimated 720 minute, and that of WPAC was estimated 640 minute to reach the breakthrough. From the above results, it is possible to replace the coco-nut shell activated carbon with wasted paint activated carbon.

• Journal of Conservation Science
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• v.37 no.4
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• pp.391-401
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• 2021

Outdoor sculptures of modern art works are being damaged and deteriorated as they are exposed to the outdoor environment due to the nature of exhibition in the outdoor environment, but secure of basic data through the measures for conservation and advanced researches still remain in the early stage. The surface of "Conversion" which is exhibited in the Busan Cheonmasan Sculpture Park has been exfoliated and deteriorated due to outdoor exhibition for a long time, so systematic conservation and management of works are considered necessary. Prior to the conservation and management, this study conducted observation of cross section, analysis of inorganic components, FT-IR, Raman and Py-GC/Mass analysis to examine the nature and type of paints used for the work through a scientific analysis. As a result of analysis, paints used for the "Conversion" include paint mixed with silvery aluminium powder and white pigment, reddish paint mixed with toluidine red, bluish paint that mixed prussian blue and titanium white and mixture of phthalocyanine blue and titanium white. The result is expected to be used as basic data for selecting materials necessary for conservative treatment of and establishing a plan for conservative treatment of the "Conversion".

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.31-32
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• 2019

In this study, oxidized graphene nanoplatelet(GO) was prepared by oxidizing graphene nanoplatelet(GNP) with nitric acid in order to solve the problem of dispersion of GNP, one of nano materials. GNP/Epoxy and GO/Epoxy paint were prepared by mixing GNP, GO with 0.1, 0.3, 0.5 and 1.0 wt.% in epoxy paint and the mechanical properties were evaluated. As a result, GNP/Epoxy and GO/Epoxy paints showed better mechanical properties than Neat Epoxy which did not incorporate GNP, GO. Especially, when 0.3 wt.% of GO was incorporated into epoxy resin, it showed higher tensile strength than Neat Epoxy. It was confirmed that acid treatment of GNP was effective in improving the mechanical properties of epoxy paint. However, graphene material was found that it was not effective in improving the bond performance of the epoxy paint.

• Applied Chemistry for Engineering
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• v.22 no.1
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• pp.45-47
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• 2011

Novel antibacterial N-halamine materials with alkyl group were prepared for paint application. Using E. coli and Fungi, antibacterial property of the dichloro hexyl isocyanuric acid (DCHICA) was determined and influences of the antibacterial agent's concentration and the bacteria test time on the antibacterial ability were also investigated. It was also observed that the film made using DCHICA showed better surface biocidal activity against the bacteria and fungi than that of dichloroisocyanuric acid (DCICA) in the absence of alkyl chains.

• Journal of the Korea Society of Computer and Information
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• v.28 no.2
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• pp.209-216
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• 2023

This paper aims to develop a model to estimate the paint thickness in a shipyard spray painting according to changes of spraying distance and speed. We acquired the experimental datasets of five different conditions with respect to the spraying distance and speed using a painting robot. In addition, we applied a preprocessing step to handle noises which might be caused by various reasons such as a nozzle damage. Our method is to transform a thickness function of a specified spraying distance and speed into another function of an unknown spraying and speed. We observed that the proposed method shows more stable and more accurate predictions compared with an artificial neural network-based approach.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.35-36
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• 2023

Safety management of steel frame members is a very important part to maintain safety and function. However, precise inspection is not possible for steel frame members due to finishing materials and insulation materials, leading to poor inspection. For steel members, an insulating spray coating method is used for high thermal conductivity. The insulation spray method is not only uneconomical, but also has the disadvantage of spoiling the aesthetics. In addition, VOCs are released from paints used in spraying, so a solution is needed. In this study, heating paint was used to improve the disadvantages of the insulation spray coating method and the high thermal conductivity of steel frame members. In addition to this, in order to reduce VOCs generated from the paint, active clay was added to produce a functional exothermic paint, and then the experiment was conducted. As the amount of activated clay increased, the film thickness increased, and the VOCs emission and thermal conductivity decreased.