fluoresceins
plural of fluorescein
Source: Wiktionary
Flu`o*res"ce*in, n. (Chem.)
Definition: A yellowish red, crystalline substance, C20H12O5, produced by heating together phthalic anhydride and resorcin; -- so called, from the very brilliant yellowish green fluorescence of its alkaline solutions. It has acid properties, and its salts of the alkalies are known to the trade under the name of uranin.
Source: Webster’s Unabridged Dictionary 1913 Edition
24 October 2024
(noun) a closed plane curve resulting from the intersection of a circular cone and a plane cutting completely through it; “the sums of the distances from the foci to any point on an ellipse is constant”
The earliest credible evidence of coffee-drinking as the modern beverage appeared in modern-day Yemen. In the middle of the 15th century in Sufi shrines where coffee seeds were first roasted and brewed for drinking. The Yemenis procured the coffee beans from the Ethiopian Highlands.
