Yield flowering

Quenched sulfur vapor has been studied for a long time. Slowly quenched to room temperature it yields flowers of sulfur, which were prepared by alchemists. The flowers can be separated into several phases by elution with CSg. Thermal alnalysis 19) shows that a-sulfur, j3-sulfur, and oD-sulfur are present. The latter melts at 104°C. The X-ray structure of a -sulfur, prepared in this way, and that of Crystex 104), a widely used insoluble form of sulfur, ateo called supersublimation sulfur, are not... 

Pommade. These are botanical extracts prepared by the enfleurage method wherein flower petals are placed on a layer of fat which extracts the essential oil. This method is appHed to low odored flowers, which do not yield appreciable oil on steam or water distillation, or flowers of valuable but dehcate odor (such as jasmin), which are destroyed on such treatment. Pommades, as such, are seldom used by the industry at present (ca 1995), but are further processed to provide more concentrated extracts such as absolutes. Absolutes, being alcohol-soluble, are much more convenient forms for the perfumer. 

Exceptions to the simple definition of an essential oil are, for example, gadic oil, onion oil, mustard oil, or sweet birch oils, each of which requires enzymatic release of the volatile components before steam distillation. In addition, the physical process of expression, appHed mostly to citms fmits such as orange, lemon, and lime, yields oils that contain from 2—15% nonvolatile material. Some flowers or resinoids obtained by solvent extraction often contain only a small portion of volatile oil, but nevertheless are called essential oils. Several oils are dry-distiUed and also contain a limited amount of volatiles nonetheless they also are labeled essential oils, eg, labdanum oil and balsam oil Pern. The yield of essential oils from plants varies widely. Eor example, nutmegs yield 10—12 wt % of oil, whereas onions yield less than 0.1% after enzymatic development. 

Melia azadirachta L. (neem or margosa). The bark, according to Cornish, yields a minute amount of a bitter alkaloid, margosine. The fruit is reported to be toxic and to contain an alkaloid, azaridine. The leaves are stated to be insect-repellent and from them an alkaloid paraisine has been prepared. The flowers are alkaloid-free. ((1) Ind. Ann. Med. Sci., 1857, 4, 104 (2) Carratala, Rev. Asoc. med. Arg., 1939, 53, 338 (3) Volkonsky, Arch. Inst. Pasteur Alg rie, 1937, 427 (4) Subramanian and Rangaswamy, Curr. Sci., 1947, 16, 182.)... 

Th oil reaemhles rascmary od rather the-o laveoder oil in <>lour, h Ting a digtinctly camphoracrous smell. The dried flowers yield about 0 8 per cent, of essential oil which baa the following characters —... 

Ahapanaf/i.—The leaf is violet on the under snrfaoe, the stalk is blue and the flower white. The yield of oil is low. 

Charabot and Pdlet have prepared two samples of Spaoish vervain nil, the one distilled from the dried leaves, the other from the flowers, the respeetive yield being 0T 4 per ceut. and 0-878 per oeal, The oil from the leaves had a rotatory power of - 10° 30 , that from the flowers + fi 50 , This laUer appeared to ha more rich in citral than the former, containing 70 per cent, and about 10 por cent, of alcohols,... 

Ibt.. ot iho )ilau(., coufiisUiig ot th< cntiic act ms with leaves aud flowere, yielded 0 011 [ler uent. of oil haviog th followiiia chaiaelitrs —... 

There are two flowerings annually, and the tree only yields fruits... 

The perfume of the flowers of the Philippine Champaca is stronger aud sweeter than that of the Singapore, Penang, Colombo, and Pera-deniya flowers. It wonld appear that it is the same with this tree as with the ylang, which doiss uot yield tbe same essential oil in Java, Ibc Straits, or Ceyloo, as in Ibe Philippines. ... 

The fresh flowers of the mignonette, Heicda odoratu, yield traces, about -002 per oeut., of an essential oil of eieecdingiy powerful odour. This oil is semi-solid at ordinary temperatures, and its cberaistnr is not uoderslood, as the oil is in itself so very rare. Indeed, commercially, -an ordinary floral extract is generally used in preferenoe to any direct... 

Para-cresol methyl ether occurs naturally in oil of ylang-ylang and similar flower oils. It is also prepared synthetically, and forms a useful artificial perfume for compound flower odours. It is a liquid boiling at 175°, and, as stated above, yields anisic acid on oxidation. 

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