This paper starts with the comparative research on the colors of the various metal inorganicsubstances and ends with the conclusion of 18 rules of the color change.
本文对众多金属无机物的颜色进行比较研究，得出了18个变化规律，并从理论上论证了这些规律的成立。
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The term plastic is used to define human-made polymer resins containing carbon atoms covalently bonded with other elements, along with organic or inorganicsubstances.