Diphenylamine Sulfonic Acid as a Reagent for the Colorimetric Determination of Nitrates

Abstract

higher than integral, the accuracy claimed being 0.01 per cent. In converting from the physical to the chemical scale, if the higher factor of Mecke and Childs, 1.00022, is used, the atomic weight of radium lead falls between 205.96 and 206.00. However, if the latter is always accompanied by actinium lead, Pb207, in the proportions found in Katanga lead by Aston4 (93.3:6.7) the average atomic weight of uranium lead should be 0.07 unit higher, a difference far outside the apparent accuracy of our experiments. This suggests the possible presence in uranium lead of lead isotopes of lower atomic mass than 206. An alternative is that the atomic weight of lead as found by us is too low, or that the packing fraction of lead determined with the mass spectrograph is incorrect.The experimental result of this research is that the atomic weight of uranium lead from a specimen of cyrtolite is 205.92 ± 0.02.(4) Aston, Nature, 129, 649 (1932).

Urinary Colorimetric Sensor Array and Algorithm to Distinguish Kawasaki Disease from Other Febrile Illnesses

“…cysteinyl leukotrienes, nitrite or nitrate, and neopterin) [ 20 – 22 ], naturally occurring peptides [ 12 ], and proteins [ 23 ], might serve as the targets for the colorimetric sensor array. For example, the sensing compounds diphenylamine and barium diphenylamine-4-sulfonate, previously used for the colorimetric determination of nitrates [ 24 , 25 ], form oxidation products in chromogenic reaction with urinary nitrate. Further work should clarify the nature of the distinct urine constituents that account for the diagnostic pattern in KD patients.…”

Design and Fabrication of a Highly Stable Polymer Carbon Nanotube Nanocomposite Chemiresistive Sensor for Nitrate Ion Detection in Water

“…[40][41][42]58,59 Phenyl aniline molecule has been used in detection of nitrate ion. [60][61][62] In this study, phenylaniline moiety is coupled to thiourea. Phenylaniline-thiourea forms a neutral receptor molecule which is capable of hydrogen bonding with nitrate ion.…”

Diphenylamine Test for Nitrates in Mixtures of Cellulose Esters

“…The methanol is separated by distillation, and oxidized to formaldehyde by means of an acid solution of potassium permanganate (3), and the formaldehyde is determined by a modified colorimetric method (5,6).…”

“…An investigation was made of the speed and strength of color development when solutions containing diphenylamine and water were brought into contact with films cast from mixtures of cellulose esters covering DIPHENYLAMINE in sulfuric acid has long been known {6) as a sensitive reagent for indicating the presence of nitrates by the production of a blue coloration. Because the blue color results from the oxidation of the diphenylamine, strong oxidizing agents such as nitrite, chromate, ferric salts, etc., interfere (5).…”