Reade conjectured that the difference in sensitivity was caused by gallic acid used for tanning, and indeed by treating paper with gallic acid before soaking it in silver nitrate solution, he could drastically increase the sensitivity.
42.
Reade conjectured that the difference in sensitivity was caused by gallic acid used for tanning, and indeed by treating paper with gallic acid before soaking it in silver nitrate solution, he could drastically increase the sensitivity.
43.
The plant contains diverse phytochemicals, including ursolic acid, tannic acid, gallic acid, some essential oils and resin, hydroquinones ( mainly arbutin, up to 17 % ), tannins ( up to 15 % ), phenolic glycosides and flavonoids.
44.
Because of its short shelf life ( changing to pale violet color ) it is sometimes prepared by dissolving gallic acid into ethanol and adding the sulfuric acid at the time of testing from a separate bottle.
45.
The compound is soluble in dioxane, from which it crystallizes as red needles that sublime without melting at 365 �C . It can be obtained by treating gallic acid with concentrated sulfuric acid and then with sodium hydroxide.
46.
When wanted for use, the side initially brushed with silver nitrate was now brushed with a " gallo-nitrate of silver " solution consisting of silver nitrate, acetic acid and gallic acid, then lightly blotted and exposed in the camera.
47.
In 1818 the French chemist and pharmacist Henri Braconnot ( 1780 1855 ) devised a simpler method of purifying gallic acid from galls; gallic acid was also studied by the French chemist Th�ophile-Jules Pelouze ( 1807 1867 ), among others.
48.
In 1818 the French chemist and pharmacist Henri Braconnot ( 1780 1855 ) devised a simpler method of purifying gallic acid from galls; gallic acid was also studied by the French chemist Th�ophile-Jules Pelouze ( 1807 1867 ), among others.
49.
When they added a subset of the nonwater-soluble compounds _ syringic acid, gallic acid and coniferaldehyde _ to the whiskey, a second group of tasters, regular drinkers of Jack Daniel's, but not trained to pick out the nuances, tasted no difference.
50.
The gallic acid dimer, ellagic acid ( M . W . 302, right ), a molecule at the core of naturally occurring phenolic compounds of varying sizes, is itself not a polyphenol by the WBSSH definition, but is by the Quideau definition.
