Orange natural

Steady-state liuninescence of topaz has been studied by Tarashchan (1978). At 77 K narrow lines at 680,696,712 and 730 nm have been ascribed to single Cr (R-Unes) and Cr +-pairs (M-lines). We studied two transparent, four yellow and one orange natural topaz. The two transparent precious stones have not been subjected to destructive chemical analyses. In other samples their Cr, Mn and V concentrations have been measured by ICP-AS method (Table 4.17). The absorption spectrvun typical for Cr + has been detected only in red topaz with the highest Cr content of 500 ppm. The spectrum clearly revealed two broad bands typical of the octahedrally coordinated Cr + (Gaft et al. 2003a). The bands centered at 418 and 533 nm evidently correspond to the spin-allowed A2g T2 and A2 transitions, respectively. The peak attributed to the spin-forbidden A2 Eg transition is located near 685 nm, while other very weak lines at 696 and 712 nm are also present. 

Hans Brockmann, a pioneer of research on antibiotics, pubhshed the isolation and structure elucidation of the first anthracyclines. According to his definition [1], anthracychnes are red to orange natural or synthetic dyes with a skeleton of 7,8,9,10-tetrahydro-tetracene-5,12-quinone and mono- to tetrasaccharide moieties attached, usually to ring D of the aglycone. In this review, the numbering system proposed by Brockmann (see structure 1) will be used. 

Figure 35.26. Sky, silica aerogel, 20 x 20 x 10 cm. Thanks to a black and glossy surface, we can see the magnificent sky-blue and sunset-orange natural colors of the artwork. One of the author s projects in progress is to realize silica aerogel sculptures where the clouds could appear, move, and disappear into the sculpture... Hopefully with the help of the scientific community specialized on aerogels (photographs and copyright MICHALOUS, 2009).

Aqueous solutions containing titanium(IV) give an orange-yellow colour on addition of hydrogen peroxide the colour is due to the formation of peroxo-titanium complexes, but the exact nature of these is not known. 

Copperil) oxide, CujO, occurs naturally as the red cuprite. It is obtained as an orange-yellow precipitate by the reduction of a copper(II) salt in alkaline solution by a mild reducing agent, for example glucose, hydroxylamine or sodium sulphite ... 

Many esters occur naturally Those of low molecular weight are fairly volatile and many have pleasing odors Esters often form a significant fraction of the fragrant oil of fruits and flowers The aroma of oranges for example contains 30 different esters along with 10 carboxylic acids 34 alcohols 34 aldehydes and ketones and 36 hydrocarbons... 

Bertotti, M. Vaz, J. M. Telles, R. Ascorbic Acid Determination in Natural Orange Juice, /. Chem. Educ. 1995, 72, 445M47. 

Another group of natural flavoring ingredients comprises those obtained by extraction from certain plant products such as vanilla beans, Hcotice root, St. John s bread, orange and lemon peel, coffee, tea, kola nuts, catechu, cherry, elm bark, cocoa nibs, and gentian root. These products are used in the form of alcohohc infusions or tinctures, as concentrations in alcohol, or alcohol—water extractions termed fluid or soHd extracts. Official methods for their preparation and specifications for all products used in pharmaceuticals are described (54,55). There are many flavor extracts for food use for which no official standards exist the properties of these are solely based on suitabiUty for commercial appHcations (56). 

In 1868, within a decade of the development of the spectroscope, an orange-yeUow line was observed in the sun s chromosphere that did not exactiy coincide with the D-lines of sodium. This line was attributed to a new element which was named helium, from the Greek hellos, the sun. In 1891 an inert gas isolated from the mineral uranite showed unusual spectral lines. In 1895 a similar gas was found in cleveite, another uranium mineral. This prominent yellow spectral line was then identified as that of helium, which to that time had been thought to exist only on the sun. In 1905 it was found that natural gas from a well near Dexter, Kansas, contained nearly 2% helium (see Gas, natural). 

Acetophenone. Acetophenone [98-86-2] (methyl phenyl ketone) is a colorless Hquid that forms laminar crystals at low temperature (mp 20°C). It has a characteristic sweet orange blossom odor, and is soluble in alcohols and ethers. It is found in nature in oil of casatoreum, obtained from beavers oil of labdanum, recovered from plants and in buds of balsam poplar. It can be prepared by the Friedel-Crafts reaction (qv) of acetyl chloride with benzene in the presence of aluminum chloride however, this route is of Htde commercial significance. 

Natural Products. The prodigiosins are antibacterial and antiftmgal orange-red pigments based on the basic pyrryl—dipyrrylmethene unit [22187-69-5] (31). 

Twenty-four years before its detection in nature PEA was first synthesized in 1876 (56) by reducing phenylacetaldehyde [122-78-1] with sodium amalgam. Then, in 1900, it was independently identified in otto of rose (57) and rose water (58). Subsequently, PEA has been identified in numerous flower oils such as ylang-ylang, narcissus, hyacinth, lily, neroH, and geranium as well as various other natural products like tea, tobacco, orange juice, beer, cigarette smoke, etc. 

The first chromium compound was discovered in the Ural mountains of Russia, during the latter half of the eighteenth century. Crocoite [14654-05-8] a natural lead chromate, found immediate and popular use as a pigment because of its beautihil, permanent orange-red color. However, this mineral was very rare, and just before the end of the same century, chromite was identified as a chrome bearing mineral and became the primary source of chromium [7440 7-3] and its compounds (1) (see Chromiumand chromium alloys). 

The chief coloring principle found ia the oil or fat extracts of annatto seeds is the carotenoid hixin (36, R = UH3) (Cl Natural Orange 4, Cl No. 

The colorant is used at 2—50 ppm as pure color to shade margarine, shortening, butter, cheese (4 ), baked goods, confections, ice cream, eggnog, macaroni products, soups, juices, and beverages (58). Its chief advantages over other colorants are its nutritional value and its abiUty to dupHcate natural yellow to orange shades. 

Heima [83-72-7]—Cl Natural Orange 6, Cl No. 75480. The dried leaf and petiole of Camoma alba Cam [Lamoma inermis L.) (66). 

Copper Oxides. Coppet(I) oxide [1317-39-17 is a cubic or octahedral naturally occurring mineral known as cuprite [1308-76-5]. It is ted or reddish brown in color. Commercially prepared coppet(I) oxides vary in color from yellow to orange to ted to purple as particle size increases. Usually coppet(I) oxide is prepared by pytometaHutgical methods. It is prepared by heating copper powder in air above 1030°C or by blending coppet(II) oxide with carbon and heating to 750°C in an inert atmosphere. A particularly air-stable coppet(I) oxide is produced when a stoichiometric blend of coppet(II) oxide and copper powder ate heated to 800—900°C in the absence of oxygen. Lower temperatures can be used if ammonia is added to the gas stream (27-29). 

Bixia [6983-79-5] (Cl Natural Orange 4 CI75120) (45) is found ia the seeds of the plant Bixa orellana native to India. 

D-limonene (Florida Chemicals). A compound of optically active terpene (CioHie) derived as an extract from orange and lemon oils limited data shows veiy low viscosity at low temperatures—only one centipoise at —50°C natural substance having questionable stabihty, Theiminol D-12 (Mon.santo). A synthetic hydrocarbon clear liquid ... 

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