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A nitrite test is a standard component of a urinary test strip. A positive test for nitrites in the urine is called nitrituria. This test is commonly used in diagnosing urinary tract infections (UTIs). A positive nitrite test indicates that the cause of the UTI is a Gram-negative organism, most commonly Escherichia coli. The reason for nitrites ...
In organic chemistry, an azo coupling is an reaction between a diazonium compound (R−N≡N +) and another aromatic compound that produces an azo compound (R−N=N−R’).In this electrophilic aromatic substitution reaction, the aryldiazonium cation is the electrophile, and the activated carbon (usually from an arene, which is called coupling agent), serves as a nucleophile.
Therefore, they are used as dyes, and are commonly known as azo dyes, an example of which is Disperse Orange 1. Some azo compounds, e.g., methyl orange, are used as acid-base indicators due to the different colors of their acid and salt forms. Most DVD-R/+R and some CD-R discs use blue azo dye as the recording layer. The commercial success of ...
To prevent future buildup of extrinsic stains, identification of the cause (e.g., smoking) is required. Intrinsic discoloration generally requires one of the many types of tooth bleaching . Alternatively the appearance of the tooth can be hidden with dental restorations (e.g., composite fillings, veneers , crowns).
The nitrite test is commonly used to diagnose urinary tract infections by measuring the concentrations of nitrite in solution, indicating the presence of a gram-negative organism. A simple nitrite test can be performed by adding 4 M sulfuric acid to the sample until acidic, and then adding 0.1 M iron (II) sulfate to the solution.
Azo pigments are similar in chemical structure to azo dyes, but they lack solubilizing groups. [8] Many so-called azo pigments are not strictly classifiable as azo compounds since they exist as keto hydrazide tautomers, which lack the -N=N- linkage. C.I. Pigment Yellow 12, an azo pigment (also classified as a diarylide pigment).
Mordant red 19 is a typical mordant dye. Like many mordant dyes, it features the azo group (RN=NR) and various sites for chelating to metal cations. A French Indienne, a printed or painted textile in the manner of Indian productions, which used mordants to fix the dyes
Example(s) dacry(o)-of or pertaining to tears: Greek δάκρυ, tear dacryoadenitis, dacryocystitis-dactyl(o)-of or pertaining to a finger, toe Greek δάκτυλος (dáktulos), finger, toe dactylology, polydactyly: de-from, down, or away from Latin de-dehydrate, demonetize, demotion dent-of or pertaining to teeth Latin dens, dentis, tooth