from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A bivalent organic radical, C6H4, derived from benzene by removal of two hydrogen atoms.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of three isomeric divalent aromatic radicals derived from benzene by removing two hydrogen atoms from the ortho-, meta- or para- positions.
from the GNU version of the Collaborative International Dictionary of English
- n. A hypothetic radical (C6H4) occurring in certain derivatives of benzene.
from The Century Dictionary and Cyclopedia
- n. A bivalent organic radical derived from benzene by the removal of two hydrogen atoms. Its formula is C6H4=.
Sorry, no etymologies found.
The bowls are really neat, as is his "phenolygous cubic graphite" and the phenylene macrocycles. neat stuff.
Its constitution is determined by the facts that it may be prepared by reducing nitro-azo-benzene by ammonium sulphide and that by reduction with stannous chloride it yields aniline and meta-phenylene diamine.
NH_2·C_6H_4·N_2·C_6H_3 (NH_2) _2, is prepared by the action of nitrous acid on meta-phenylene diamine.
C_6H_5·N_2·C_6H_3 (NH_2) _2, first prepared by O. Witt (_Ber. _, 1877, 10, p. 656), is obtained by coupling phenyl diazonium chloride with meta-phenylene diamine.
B, 1 lb. cotton brown N, 1 lb. soda and 10 lb. Glauber's salt, then diazotise and develop with phenylene diamine.
Cotton brown N, 1 lb. diamine fast yellow A, 1 lb. soda and 10 lb. salt, then diazotise and develop with phenylene diamine.
After dyeing rinse well in a bath containing 6 dr. soda and 3 oz. soap per 10 gallons water, diazotised in a fresh bath with 4 lb. nitrite of soda and 12 lb. hydrochloric acid (per 100 lb. of dry goods), rinse thoroughly and develop with 3 to 16 oz. phenylene diamine (93 per cent.), with addition of 1 to 2 lb. soda.
They may even be diazotised and developed with beta-naphthol and phenylene diamine.
Sometimes two developers are mixed together, in which case care should be taken that an alkaline developer naphthol or phenol be not mixed with an acid developer (phenylene diamine, naphthylamine, etc.), unless the acidity of the latter has been neutralised with soda; otherwise the developer might be thrown out of the bath in an insoluble and hence useless form.
= Toluylene diamine = is a homologue of phenylene diamine and is used in precisely the same way.