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French purple

The threads on the face of the carpet that have faded (because of their moderate lightfastness) become colorless when they are vatted with sodium dithionite and ammonia, and they turn magenta upon subsequent reoxidation in the air. This dyeing is, therefore, one made with orchil (C.I. Natural Red 28). This dye was known as French purple , and very often it was used in tapestries in the 16th-19th centuries despite its poor lightfastness. [Pg.165]

The calcium lake is used in printing, and is dissolved in acetic acid and fixed by steaming ( French purple ). The shades obtained with archil are purple, and may be modified with indigo or cochineal. [Pg.261]

Cudbear. Crottle. Common names for the lichen Ochrolechia tartarea L., Lecanoraceae and for the coloring matter from this and other lichens, especially Lecanoraceae and Roccellaceae. A source of litmus, q.v. Acids in lichens (e.g. lecanoric acid) hydrolyze to orcinol, q. v., which, in the presence of ammonia can be oxidized to the dye orcein, q.v. The dyes French Purple, Persio, Orchil, and Orseitles derive from the salts of orcein Colour Index Vol. 3 (3rd ed-, 1971) p 3241. [Pg.410]

Orsin—Dimetadioxy-toluene—CeHi(CHs)(i)(OH,)(9)(OH)(s)—exists in nature in those lichens which are used as sources of archil and litmus Rocella tinGtoria, etc.). It crystallizes in six-sided prisms is sweet readily soluble in water, alcohol, or ether fuses at 58° <136°.4 F.). Its aqueous solution is colored violet-blue by FeaCl . It unites with NHa to form a compound which absorbs O from the air, and is converted into orcein, CTH7NO3 a dark red or purple body, which is the chief constituent of the dye-stuff known as archil, cudbear, French purple, and litmus. [Pg.409]

In a discussion of archil that is, orchil q.v.) a lichen dye - Salter (1869) states that Soluble in water and alcohol, this colouring principle yields by precipitation with chloride of calcium a compound known as Sohd French Purple . Bersch (1901) adds to this, remarking that French Purple is a compound of the archil colouring matter with hme. .. a garnet red precipitate is produced . [Pg.161]

Monascus is cultivated on solid media in Asian countries to produce a red colorant named Anka and used as a food ingredient. A Chinese medical book on herbs published in the first century first mentioned the terms ang-kak and red mold rice. Red mold rice has been used as a food colorant or spice in cooking. In 1884, the French botanist Philippe van Thieghem isolated a purple mold on potato and linseed cakes and named it Monascus ruber. This ascomycete was so named because it has only one polyspored ascus. In 1895, Went isolated a mold from the red mold rice obtained from a market in Java, Indonesia. This fungus was named Monascus purpureus, after which several other species were isolated around the world. [Pg.413]

Construction of LB films having lateral d.c. conductivities is a burgeoning activity. Results of published work are summarized in Table 9 [726-772]. The first formation of a conducting LB film was reported by French workers in 1985 [726]. Non-conducting LB films were formed from N-docosylpyridinium TCNQ. Subsequent exposure to iodine vapor resulted, however, in the lateral conductivities in the order of 0.1 S cm-1 [726]. The initially formed LB film was shown to consist of (TCNQ. )2 dimers whose molecular planes were almost parallel to the substrate. Iodination resulted in the development of a brown-purple color, the partial oxidization erf the radical anions to TCNQ° and, most importantly, a dramatic rearrangement of the LB film. In iodine-doped films, the TCNQ molecules have been shown to assume a position almost perpendicular to the substrate [721, 773],... [Pg.162]

It was postulated that the inhibition of LDL oxidation by red wine may help to explain the French paradox. Since Frankel and co-workers [73] showed that red wine inhibit the oxidation of LDL, several in vitro studies have confirmed this finding [26,74,75]. There is controversy over whether or not the consumption of red wine by humans reduces the oxidation of LDL ex vivo. While several studies found resistance of LDL oxidation after 2 weeks of red wine consumption in healthy subjects [75,76], others found no effect on the oxidation of LDL ex vivo [26,77]. Recently, Stein and coworkers [78] showed that short-term ingestion of purple grape juice (7.7 1.2 mL/Kg/day for 14 days) reduced the susceptibility to oxidation in coronary artery disease patients and that this is a potential mechanism by which flavonoids in purple grape products may prevent cardiovascular events, independent of alcohol content. [Pg.579]

I waved my hands to show that they were empty and I was unarmed. To warn you, monseigneur, and your noble wife. The older man, the one with the purple robes and the fancy— I had to gesture to my shoulder, for my French did not extend to the word for tippet. Procurator Orseolo. He was poisoned at that meeting. Everyone who was present is suspect. You have heard of the Council of Ten ... [Pg.65]

Piriforme Rouge — French origin. Purple, pyriform (pear-shaped) tubers. Maintained by Institut National de la Recherches Agronomique (INRA), UMR-DGPC, Montpellier, France (INRA MPHE001417) limited immediate availability. Mesken, 1988. [Pg.218]

Tlie black-lipped pearl oyster, Pimtada margarm a, is a little smaller, and measures fiom 15 to 25 centimetres across. It, too, has silvery nacre inside the shell, becoming silvery gr at the edges, which are surrounded on the lip of the shell by a black border that resembles enamel. The oyster lives in the Indian Ocean and the western and central Pacific, eq>ecially around French Polynesia. It is used to produce the fiunous Tahitian black pearis, which are nucleated cultured pearls. The nacre secreted by these pearl oysters is naturally coloured and varies om li t gr to black, with iridescent hints of green, purple, pink and blue. The pearls rai in size from 10 to 18 millimetres in diameter. [Pg.146]

Other studies have described similar results to those found in our research, that is, that ellagitannins are more abundant in French oak (26) and therefore, in wines matured in French oak barrels. So, the presence of ellagitannins enhances the color of wine and increases absorbance at 620 nm by fevoring anthocyanin-procyanidin type tannin condensations with acetaldehyde (purple pigments) and that foct also helps to explain the higher PVPP index values of wines fix)m new French oak barrels. They also prevent the development of brick-yellow color by preventing the oxidation of phenolic compounds (24). [Pg.30]

French) or BROMOFORMO (Spanish) (75-25-2) CHBrj Noncombustible liquid. Violent reaction with chemically active metals, acetone, calcium, strong caustics, potassium, potassium hydroxide, sodium hydroxide. Increases the explosive sensitivity of nitromethane. Incompatible with crown polyethers, sodium-potassium alloys. Forms friction- and shock-sensitive compounds with lithium. Aqueous solution is a medium-strong acid. Liquid attacks some plastics, rubber, and coatings. Corrosive to most metals in the presence of moisture. Thermal decon osition products include highly toxic carbonyl bromide and hydrogen bromide fumes. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or COj extinguishers. [Pg.156]


See other pages where French purple is mentioned: [Pg.21]    [Pg.194]    [Pg.2153]    [Pg.161]    [Pg.73]    [Pg.21]    [Pg.194]    [Pg.2153]    [Pg.161]    [Pg.73]    [Pg.18]    [Pg.410]    [Pg.152]    [Pg.383]    [Pg.936]    [Pg.676]    [Pg.309]    [Pg.136]    [Pg.27]    [Pg.199]    [Pg.233]    [Pg.233]    [Pg.501]    [Pg.1753]    [Pg.515]    [Pg.7]    [Pg.157]    [Pg.4]    [Pg.50]    [Pg.32]    [Pg.83]    [Pg.130]    [Pg.149]    [Pg.205]    [Pg.366]    [Pg.367]    [Pg.410]    [Pg.418]    [Pg.420]    [Pg.599]    [Pg.648]    [Pg.681]   
See also in sourсe #XX -- [ Pg.73 ]




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