• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.44 no.3
• /
• pp.303-316
• /
• 2018

In this study, I investigated the applicability of fluorescein-derived xanthene dyes to fluorescent pigment and the controllability of the optical properties of manufactured pigments. Eosin Y (D&C Red No.22) and phloxine B (D&C Red No.28) were mainly used as a dye to prepare the pigment. Dyes dissolved in a solvent were poured into a powder dispersed in the solvent, then dried and pulverized to fabricate the pigments. Optical characteristics related with fluorescence of the prepared pigment were measured. The optical properties of pigments were varied depending on the solvent used, content of the dye in the pigment, and the ratio of dyes when more then two dyes were mixed. According to the experiment result, it seems that some of the dyes attached to the powder showed fluorescence while the rest did not contribute to it. From the result of pigment washing experiment to explore the binding (or interaction) strength and characteristics of the powder-dye system constituting the pigment, it seems that there are two or more different interactions existing in the pigment system, one of which is relatively stronger than the solvent-dye interaction.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.689-696
• /
• 2017

The practical applications of ordinary high-fluidity concrete have been limited due to several drawbacks, such as high hydration heat, high amount of shrinkage, and non-economic strength development. On the other hand, due to its advantages, such as improvement of construction quality, reduction of construction cost and period, the development of high-fluidity concrete is a pressing need. This study examined the properties of high-fluidity concrete, which can be manufactured on the low binders using a viscosity agent to prevent the segregation of materials. The optimal viscosity agent was selected by an evaluation of the mechanical properties of high-fluidity concrete among six viscosity agents. The acrylic type and urethane type viscosity agents showed the best performance within the range where no material separation occurred. The mechanical properties were evaluated to examine the optimal amount of AC and UT viscosity agent added by mixing two viscosity agents according to the adding ratio and blending them together with high performance water reducing agent. When the ratio of the AC : UT viscosity agents was 5:5, it was most suited for high-fluidity concrete with low binders by increasing the workability and effect of the reducing viscosity.

• Proceedings of the KWS Conference
• /
• 1993.05a
• /
• pp.85-87
• /
• 1993

• Proceedings of the Korean Ceranic Society Conference
• /
• 2003.04a
• /
• pp.182.1-182
• /
• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2002.11a
• /
• pp.48-49
• /
• 2002

• Proceedings of the Korean Magnestics Society Conference
• /
• 1995.10a
• /
• pp.48-49
• /
• 1995

• Proceedings of the Petrological Society of Korea Conference
• /
• 2006.05a
• /
• pp.29-29
• /
• 2006

• Proceedings of the Korean Ceranic Society Conference
• /
• 2003.10a
• /
• pp.85.1-85
• /
• 2003

• Korean Chemical Engineering Research
• /
• v.55 no.5
• /
• pp.629-637
• /
• 2017

Severe dust explosions occurred frequently in food processing industries and explosion damage increase by flame propagation in pipes or plants. However there are few fire explosion data available due to various powder characteristics. We investigated the characteristics of ignition and explosion on sugar, cornstarch and flour dust with high frequency accidents and high social demand. The measurements showed the median diameter of 27.56, 14.76, $138.5{\mu}m$ and ignition temperature has been investigated using by thermo-gravimetric analysis (TGA) and differential scanning calorimeter (DSC). The maximum explosion pressure ($P_m$) and dust explosion index ($K_{st}$) of sugar, cornstarch and flour are 7.6, 7.6, 6.1 bar and 153, 133, 61 [$m{\cdot}bar/s$], respectively. The flame propagation time in duct was calculated in order to evaluate the damage increase due to flame propagation during dust explosion. The explosion hazard increase due to flame propagation was higher in the order of sugar, flour and cornstarch dust.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.25 no.1
• /
• pp.37-54
• /
• 1999

Planarized SiO$_2$ particles were prepared by two-step reduction method of making much smaller particles, micron-sized ones, to improve spreadability, adherence, and smoothness. Various pigments known as flaky extender usually have terrace layers on their surfaces, but SiO$_2$ Particles in this study exhibit a smooth surface structure. These single SiO$_2$ particles were used for core particles to prepare the composite particles coated with ultra fine TiO$_2$ particles by a homogeneous precipitation method. The thickness and the morphology of the deposited TiO$_2$ layer could be altered by adjusting the reactant concentrations, reaction time and temperature. The characteristics of SiO$_2$/TiO$_2$composite in the field of color cosmetics is to give a UV-cut effect and to enhance the chroma of human skin color, one of optical properties.