• Journal of Digital Convergence
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• v.18 no.4
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• pp.309-314
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• 2020

Polymethyl methacrylate (PMMA) is concerned with promoting oral infection due to its low antibacterial activity. To overcome this, the nanoparticles of Ag-MSN, nGO, and CNP were mixed with MMA liquid in a weight ratio of 0, 0.25, 0.5, 1.0, 2.0% compared to resin powder using Orthocryl from Dentarum, a calibration resin, and then instructed by the manufacturer. Accordingly, a specimen for calibration was prepared by mixing PMMA: MMA (1.2: 1) ratio, and physical properties of the calibration resin, antifungal experiments, and statistical analysis were performed. As a result of antibacterial experiments, the antibacterial properties of Ag-MSN increased. In nGO, the antibacterial adhesive effect increased hydrophilicity, not a change in surface roughness. The higher the CNP concentration, the higher the antibacterial activity. This suggests its potential usefulness as an antibacterial dental material for orthodontic devices and temporary restorations.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.781-785
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• 2011

In this work, a nano-sized samaria-doped ceria(SDC) was prepared by a urea-based hydrothermal method and characterized by XRD, FESEM and TEM. It was observed that the increase in synthesis time and temperature gave rise to crystallity and particles size. Moreover, the synthesised powders had a excellent ion-conductivity(0.1 S/cm at 600~$800^{\circ}C$) which is suitable for electrolyte of intermediate temperature-solid oxide fuel cell(IT-SOFC). Subsequently for use as electrolyte for anode-supported IT-SOFC, we tried to deposit the SDC powder on a porous NiO-SDC substrate by electrophoretic deposition(EPD) method. From the FESEM observation, a compact

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.748-760
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• 2021

The purpose of the study is to examine the mediating effects of ambivalence over emotional expression and psychological flexibility on the relationship between employees' beliefs about emotional expression and attitudes toward seeking professional psychological help. The subjects of this study were 346 employees(male: 176, female:170) over the age of 19. Questionnaires including beliefs about emotional expression, ambivalence over emotional expression, psychological flexibility, attitude toward seeking professional psychological help were conducted and the collected data were analyzed by using SPSS and Macro. A summary of the results as follows. First, in the results of the correlation analysis on the primary factors had a significant correlation. Second, psychological flexibility had a mediating effect in the relationship between beliefs about emotional expression and attitude toward seeking psychological help while mediating effect of ambivalence over emotional expression was not significant. Lastly, the sequential mediating effect of ambivalence over emotional expression and psychological flexibility between beliefs about emotional expression and attitudes toward seeking professional psychological help was significant.