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ํ์ธ์! ์ค๋์ 20์ธ๊ธฐ๋ถํฐ ํ์ฌ๊น์ง ์๊ณ์ ์ฐ์๋ ์ผ๊ด๋ฌผ์ง์ ๊ดํด ์งง๊ฒ ์ค๋ช
ํด ๋ณด๋ ค๊ณ ํฉ๋๋ค. Hi everyone, today I want to discuss a bit about luminescent materials that were used on watches since the 20th Century until present time. 1898์