Aniline — Phosphoric Acid Reagent

Aniline — Diphenylamine — Phosphoric Acid Reagent Reaction (according to [16])... 

Diphenylamine—Phosphoric Acid Reagent), these condense with aniline to Schiff s... 

Derivatization reagent Thymol-sulfuric add Diphenylamine-aniline-phosphoric acid... 

To detect glycosides heat the chromatograms to 130—150°C for 15 min. Blue-grey zones are produced (detection limit prunasin 0.3—0.5 pg [18]). Flavonoids are better detected with a modified reagent of the following composition phosphoric acid (85%) — acetic acid — aniline — diphenylamine (20 ml - -100 ml + 5 ml + 5 g). 

Fig. 23.—Liquid-solid Chromatogram of Formose Sugars. [Apparatus Hitachi Type 034-0004-KLA-3B Liquid Chromatograph. Column 1.5 diam. X 50 cm, column temp. 55°. Packing Bio-Rad Resin Type AG 1 X2. Sample formose 19.65 mg/ 0.5 ml. Eluant 1, 0.25 M H.BO, pH 8.2, 385 min 2, 0.60 M H.BO., pH 10.2. Effluent flow-rate 15 ml/hr (6.0 kg/cm ) reagent flow-rate 45 ml/hr (5.9 kg/cm ). Reagent phosphoric acid + acetic acid + aniline. Reaction bath-temp. 120°. Reaction coil 0.8 diam. X 23 cm. Cell path 2 mm, wave length 365 nm. Chart speed 6 cm/hr. Scale 0-0.2 expansion. ]...

Kappelmeier [35] has suggested the use of aniline, benzylamine, and phenyl-ethyl-amine as reagents for the identification and analysis of urea in UF resins. He has provided evidence that the methylene-ether groups form a bridge between urea residues in UF resins. The use of benzylamine in particular (which yields dibenzylurea from urea derivatives), has been developed as a method of analysis. In determining the ratio of urea to formaldehyde in UF resins, the benzylamine method has been coupled with a process of formaldehyde estimation which involves depolymerization with phosphoric acid, followed by distillation into alkaline potassium cyanide solution [36]. 

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