• Fire Science and Engineering
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• v.22 no.5
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• pp.61-66
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• 2008

In this research, gel compounds containing thermochromic ingredients were manufactured and evaluated to prevent the transition hazards of fire and explosion, which they are one of the methods for detecting abnormal conditions caused by overheating of special materials early. And also, compounds of viscoelastic and brushing types were manufactured as the kind and content of raw materials, and manufacturing process to enlarge the application for overheat-detecting targets. Test methods were conducted as chromism test, viscosity profile, starting time of thermochromism, and FT-IR analysis. Thermochromic gel materials exhibit chromism properties that can detect abnormal conditions effectively, and then they are possible to various applications.

• Journal of Biomedical Engineering Research
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• v.43 no.4
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• pp.271-279
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• 2022

Functional cosmetics containing various ingredients that improve skin health are currently being developed. In addition, technologies that help increase the absorption rate of such cosmetics have recently gained significant attention. Sonophoresis is a method to increase the transdermal absorption of cosmetics using ultrasound. A skin-mimicking phantom was fabricated using polydimethylsiloxane, Strat-M^TM membrane, and thermochromic pigments. Gel-type cosmetics used in skin mask packs and epidermal-growth-factor-based nano-cosmetics were tested for their absorption rates at ultrasound frequencies of 1, 3, and 10 MHz in the single frequency mode, and 1/3 and 3/10 MHz in the dual frequency mode. The gel-type cosmetics and epidermal-grow-factor-based nano-cosmetics showed the highest absorption rate at 3/10MHz dual frequency. The size of the cosmetic particles decreased by 5-9 %. Furthermore, the temperature rise caused by ultrasound could be visually recognized by the thermochromic pigment in the phantom turning white. We presented a skin-mimicking phantom. The device can be customized according to the size of the ultrasound probe and has the advantage of quantitatively evaluating the transdermal permeability of cosmetics at a low cost. The development of the skin-mimicking phantom will be useful for determining the suitable conditions required to increase the absorption rate of cosmetics using ultrasound.