Brilliant Violet

In the known absence of bromoform, iodoform, chloral, and other halogenated methanes, the formation of phenyhsonitrile with aniline provides a simple and faidy sensitive but nonspecific test for the presence of chloroform, the carbylamine test. Phenyhsonitrile formation is the identification test given in the British Pharmacopoeia. A small quantity of resorcinol and caustic soda solution (10% concentration) added to chloroform results in the appearance of a yellowish red color, fluorescing yeUow-green. When 0.5 mL of a 5% thymol solution is boiled with a drop of chloroform and a small quantity of potassium hydroxide solution, a yellow color with a reddish sheen develops the addition of sulfuric acid causes a change to brilliant violet, which, diluted with water, finally changes to blue (33). 

Hofmann himself made a fabulously brilliant violet that replaced Perkin s mauve, even though the professor s dye was not as fast as his student s. Dyers thought no one would want fleeting tints, but, no matter, the experts were wrong. Women craved raucous and dramatic hues they... 

Activated sludge from a full-scale plant Remazol brilliant violet Remazol black b SBR 24 h sequencing batch... 

Fig. 3.100. Chemical structures of (A) Remazol brilliant orange 3R (B) Remazol black B and (C) Remazol brilliant violet 5R. Reprinted with permission from N. Supaka et al. [158].

Exercise 26-13 Reduction of the carbonyl group of quercetin gives a substance that loses water readily to give a brilliant-violet compound. This compound, when treated with hydrochloric acid, is converted reversibly to a red salt. Consider possible ways that the reduction product could dehydrate to give a violet substance and show how addition of a proton to it could occur in such a way as to give a substantial color change. 

Crystal violet, methyl violet, brilliant violet, ethyl purple, h benzyl violet, Hofmann s violet, chrome violet Rosolc red, resole scarlet Janus red, diazine red w < 3 [Pg.427]

A redder and brighter shade is obtained with isoviolanthrone. Its halogenation products are marketed as brilliant violet dyes. Related to violanthrone is the alkaline ring-closure product of 3-pyrazolanthronylbenzanthrone, which is used as a navy blue vat dye. 

Other dyes that can be used in this procedure are Indanthrene Brilliant Violet and Indanthrene Yellow. 

The monosulphonic acid forms brilliant violet needles, which are sparingly soluble. Its salts are yellow, and mostly well crystallised. 

Triphenylmethane chelating reagents, other than CAS and ECR, have also been used to determine beryllium, e.g. Aluminon [34,35], Xylenol Orange [36], Brilliant Violet B [2], and Chromal Blue G (e = 3.1-10 ) [37]. A considerable increase of sensitivity is obtained by using Chromal Blue G in the presence of CTA (e = 9.4-10 at 626 nm) [38]. 

The following triphenylmethane dyes have been employed for determination of Sc similarly to Xylenol Orange Methylthymol Blue [33], Chrome Azurol S [34,35], Chromal Blue G [36], and Eriochrome Brilliant Violet B [37]. Much higher sensitivities have been obtained in the presence of some cationic surfactants [38 0]. In the method with Chrome Azurol S and Zephiramine, the e value is 1.5-10 at 610 nm, and in the method with Eriochrome Cyanine R and CP, e = 9.2-10" at 600 nm [40]. When o-hydroxy-quinonephthalein and CP are used, the molar absorptivity is 1.1-10 at 555 nm [41], Scandium has been determined with the use of Nile Blue in a poly(vinyl alcohol) medium [42]. 

One such pigment is Carbazole Violet, Pigment Violet 23 (XXXIX) (52) synthesized as shown in Scheme XV. It is a brilliant violet... 

Native Cassia angustifolia (CA) seed gum with 1 mL of PAC stock solution at highly acidic pH (pH = 2.5) has been shown to remove 35% Acid Sendula Red, 22% Direct Kahi Green, and 16% Reactive Remazol Brilliant Violet dyes [9] while at alkaline pH (pH = 10) under identical conditions, the decol-orization efficiency of CA is reported to be about 80%, 99%, and 45% for acid, direct and reactive dyes, respectively. CA acts as a good working substitute... 

When some of the intermediate fractions have become the brilliant violet color characteristic of neodymium, the solvent may be changed from water to 6 W HNO3... 

Carboxy 5-methyl-4-oxo-2,5-cyclohexadien-1-ylidene)[2-chloro-4-(diethylamino)phenyl methyl -2-hydroxymethylbenzoic acid, 9CI. 2"-Chloro-4"-diethylamino-4 -hydroxy-3,3 -dimethylfuchsone 5,5 -dicarboxylic acid. C.I. Mordant violet 28. C.I. 43570. Brilliant monochrome violet. Omega chrome brilliant violet B [7452-52-0]... 

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