• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.331-338
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• 2008

Coal-tar enamel, blown asphalt and polyethylene have been used as wrapping materials of steel pipe in Korea. Currently, every manufacturer produces wrapped steel pipes with different materials and methods, and little research has been performed to get on wrapping methods and materials. In this research, properties of wrapping material of steel pipe used for water supply have been evaluated. All of the materials tested in this work were found to meet the standard. Among the wrapping materials of steel pipe tested, blown asphalt and coal-tar enamel were reasonable in price, and their mechanical properties were excellent. The quality of the wrapped steel pipes was being melted easily in organic solvent. When coated thick, the load of the steel pipes was higher than necessary. Tensile strength of cathode exfoliation and PE 3-layer wrapping method was excellent. The pulling intensity of T-Die PE 3-layer was stronger than PE fluidized in PE wrapping method. Cathode exfoliation area was smaller than PE fluidized. Mechanical property and thermo-property of T-Die PE 3-layer were excellent and its anti-chemical property was great. Liquid epoxy can change the property of coating materials depending on the hardening condition and resin selection. Polyurethane used in this test showed a less adhesive strength with steel pipes than epoxy. Moisture absorbance rate was higher than Epoxy's, however. To utilize polyurethane as wrapping materials, basic property of the matter should be improved followed by finding the best suited coating condition. The method of PE 3-layer by extrude method appeared to be the best in this study. However, identification of other wrapping materials requires further additional tests.

• The Korean Journal of Cytopathology
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• v.4 no.2
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• pp.166-170
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• 1993

We describe the cytologic features of metastatic ameloblastoma which presented as multiple bilateral lung nodules. The patient was a 22-year-old male who had recurrent ameloblastoma of the mandible 7 years after the diagnosis of primary lesion. Fine needle aspiration of one of the pulmonary nodules revealed patchy arrangement of cell clusters with outer palisading columnar cells and inner irregular loose polygonal cells. Most of tumor cells had plenty cytoplasm and ovoid nuclei which lacked either pleomorphism or hyperchromatism. The cytologic findings corresponded with histologic features of the primary site which was also benign looking ameloblastoma.

• Conservation Science in Museum
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• v.12
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• pp.25-34
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• 2011

This study examined conservation process of white porcelain bottle with phoenix and peony design poly chrome, recovery of golden powder painted porcelain being damaged and colored, and recovery material and conservation methods by using a variety of experiments. Not only traditional method but also modern method can recover golden powder painted area being damaged and/or peel off, and suitable recovery was found out by using experiments. The golden powder paint of pattern edge was recovered not by traditional method but by modern method of golden powder paint with acrylic paint and binder.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.202-205
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• 1995

Developed controller is the part of deflection yoke winding machine which controls the power to form the deflection yoke coil into desired shape after winding. So as to form the deflection yoke coil, it is needed to melt the bonding material which is spreaded on the coil. The heat melt the bonding material which is produced by flowing the current through the winded coil. Therefore, at first it is needed to peel off the enamel from the winded coil so as to flow the current, and then supply the power to produce the heat which form the winded coil into desired shape. Naturally developed controller is composed of the peeling part and the conduction and forming part. All of them consist of the inverter structure and control the output current. The peeling is achieved by low voltage and high AC current, the conduction and forming is by DC current. Developed controller also has a function that detect the resistance of the deflection yoke coil to prevent the damage of the load which is produced by poor peeling.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.28 no.5
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• pp.206-210
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• 2018

Two kinds of bioactive glass were coated on the Ti6Al4V alloy by the enameling technique. In order to reduce the thermal stress due to the difference in expansion coefficient with the alloy with the secondary coating forming hydroxyapatite, the difference in expansion coefficient between the alloy and the two glasses was adjusted at $2{\times}10^{-6}/^{\circ}C$ intervals. FE-SEM and EDS analysis showed that good adhesion was formed between the Ti6Al4V alloy and the primary coating by diffusion bonding. After immersion in SBF solution, it was confirmed from FT-IR that hydroxycarbonate apatite formed in the secondary coating was not different from bulk bioactive glass.

• Resources Recycling
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• v.21 no.3
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• pp.48-55
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• 2012

Recently, the recycling with environmentally friendly method has been an issue for various fields. An effective removal method of coating layers from coated copper wires is one critical factor for recycling copper wire. We have adopted a high frequency heating routine for removing the coating layers on the coated copper wires, and attempted to find optimum conditions. The experimental results show that the copper wires should be maintained at or above $950^{\circ}C$ for rapid removal of the polyester. The simulation and experimental results are discussed with respect to the microstrucrual evolution during heating of the copper wires.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.189-194
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• 2019

This thesis aimed to apply the 3D-printing technology rapidly introduced to the overall industry to jewelry design. In the results of examining preceding researches, out of 3D-printing methods, the FMD method was used the most in design area. However, for jewelry design, the 3D-printing is used for casting process out of production processes, so that the printing method is not FMD, but DLP. Thus, the researcher examined the material functions and applicability of jewelry design through research works, by applying the 3D-printing in DLP method to jewelry design. In the results, brooches were completed by applying the 3D-printing to the jewelry design with no casting process, and then utilizing enamel and pure silver together. Producing light and solid completed products in various colors, they were verified as applicable materials. Also, as the size and form of curved design mainly used for non-geometric jewelry design could be accurately predicted through Rhino CAD, diverse possibilities of advancement to be easily used for the development of formative form of jewelry design in the future were revealed.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.109-120
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• 2004

INTRODUCTION: The build-up method has been used for application of porcelain powder on the metal framework to make final tooth shape conventionally. This method takes time and need skill to mimic final shade and shape of porcelain fused to metal crown. The purpose of this study was to develop standard shape and shade laminating porcelain forms to reduce build-up time. METHODS: To make tooth form porcelain paste, several liquid organic compounds were added to conventional feldspathic porcelain. The amount of additives and rheologic property were tested to find out best composition. Comparison of mixing methods to reduced porosity, proper heating schedule, and measurement of shrinkage amount and residual organic materials were performed to set-up standard procedures. Finally, biaxial flexural strength and color of preformed laminated paste porcelain were compared with those of porcelain which fabricated by the conventional build-up method. RESULTS: There was no significant difference in physical properties and color stability between two fabrication methods after various testing methods. Conclusion: This new build-up method can be applied to fabricate the PFM crown and bridge without any loss of strength and optical properties.

• The korean journal of orthodontics
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• v.40 no.4
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• pp.260-266
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• 2010

Objective: The aim of this study was to determine whether different types of adhesive systems and enamel-protective agents will affect the tensile bond strength of lingual brackets. Methods: A total of 75 extracted mandibular incisors were randomly divided into 5 groups and lingual brackets were bonded. Group 1 specimens received Transbond XT (3M Unitek, Monrovia, CA, USA), Group 2 required the application of a fluoride-releasing resin (Ortho-coat, Pulpdent, Watertown, MA, USA) with Transbond XT, Group 3 specimens received a chlorhexidine varnish (Cervitec Plus, Ivoclar Vivadent, Schaan, Lichtenstein) with Transbond XT. In Group 4, a light-cured orthodontic adhesive (Aegis Ortho, Bosworth, Skokie, USA) was applied and in Group 5, an antimicrobial self-etching primer (Clearfil Protect Bond, Kuraray, Osaka, Japan) was used. Results: There were no significant differences in bond strength whether fluoride-releasing resin or chlorhexidine varnish were used or not. Group 5 had significantly higher bond strength and adhesive remnant index (ARI) values than other groups (p < 0.001). The application of enamel-protective products did not have an adverse affect on the bond strength of lingual brackets. Conclusions: These products might provide benefits both for the patient and the clinician, by supporting the oral hygiene during lingual orthodontic treatment. The higher ARI score may be beneficial for Clearfil Protect Bond but its excessive bond strength should be considered in clinical practice, especially where the enamel is thin.

• Journal of Environmental Health Sciences
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• v.43 no.2
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• pp.103-110
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• 2017

Objectives: This study was performed to provide basic data for the re-establishment of standards (criteria) and analytical methods for hazardous metals in nail enamel. Methods: Ten metals (lead; Pb, arsenic; As, cadminum; Cd, antimony: Sb, cobalt; Co, nikel; Ni, copper; Cu, chromium; Cr, aluminum; Al, and mercury; Hg) were measured in 67 commercial nail enamels containing glitter and/or pearls. The content of hazardous metals (excepting Hg) was determined by using an inductively coupled plasma-optical emission spectrophotometer (ICP-OES) after microwave digestion. Mercury content was measured by a mercury analyzer without any preparation. Results: The detected ranges of the intact samples were as follows: $ND-1.756{\mu}g/g$ for Pb, $ND-1.24{\mu}g/g$ for As, ND for Cd, $ND-20.41{\mu}g/g$ for Sb, $ND-12.36{\mu}g/g$ for Co, $ND-7.908{\mu}g/g$ for Ni, $0.088-79.27{\mu}g/g$ for Cu, $0.281-18.54{\mu}g/g$ for Cr, $13.78-3563{\mu}g/g$ for Al, and $ND-0.044{\mu}g/g$ for Hg. After centrifugation, the detected ranges of supernatant were as follows: $ND-0.435{\mu}g/g$ for Pb, $ND-0.504{\mu}g/g$ for As, ND for Cd, $ND-0.035{\mu}g/g$ for Sb, $ND-13.17{\mu}g/g$ for Co, $ND-0.232{\mu}g/g$ for Ni, $0.117-90.07{\mu}g/g$ for Cu, $0.174-2.787{\mu}g/g$ for Cr, and $9.459-1565{\mu}g/g$ for Al. The results of this analysis showed that the levels of heavy metals such as Pb, As, and Sb were much higher in the intact samples than those of supernatant. Conclusion: In the present study, we found that the levels of hazardous metals were significantly different depending on the status of the presence of glitter. Based on the results, we recommend that the product consumer refrain from prolonged application of nail enamel, avoid biting or chewing the nails, and wear gloves during cooking and washing dishes.