Natural origin

S. Arctander, Petfume and Flavor Materials of Natural Origin, 1960. 

Brackets signify a trivial name no longer ia use. At 101.3 kPa = 1 atm unless otherwise noted ia kPa as a subscript. At 20°C unless otherwise noted by a superscript number (°C). At 20°C unless otherwise noted. To convert to cal, divide by 4.184. 70°C. Heat of combustion (Uquid). At50°C. To convert kPa to mm Hg, multiply by 7.5. In the alkenoic series of molecular formula 2 2 metbacrylic, undecjlenic, oleic, and emcic acids have important appHcations (Table 2). Acryhc and metbacrylic acids have a petrochemical origin, and undecylenic, oleic, and emcic acids have natural origins (see Acrylic ACID AND DERIVATIVES Methacrylic acid and derivatives). Table 2. Physical Properties of the Straight-Chain Alkenoic Acids, (2n-2) 2 ... 

The first synthetic dyestuff, mauveine, was discovered by Perkin in 1856 in the UK and led to many investigations of the derivatives of coal tar as potential coloring matters. The first dia2onium salt derived from picramic acid was prepared in 1858 and is still the basic chemistry behind coundess commercial products. Despite these inventions, in 1900 the vast majority of dyestuffs were still of natural origin. Now at the end of the century the situation has changed dramatically synthetic dyes dominate. 

Many fluids of natural origin contain detectable quantities of high molecular weight organic anions, such as those from humic, fulvic, and tannic acids, which can be carried to and deposited on AX membranes. Such deposits can behave as thin films partially selective to cations (6). The iaterfaces between such films and the undedyiag AX membranes then act as very thin stagnant depletion compartments and the AX membranes may exhibit polarization at current densities that are much lower than would be expected for new membranes ia the abseace of such anioas. 

Nuclear-physical methods ai e the basic ones in controlling environmental pollution which results from nucleai -power complexes and power plants work. Oil and gas production leads to the extraction of radio nuclides of natural origin in considerable amounts, which later spread from oil-slimes and water wastes in the neighborhoods of oil and gas producing entei prises. Similaidy, toxic and radioactive elements can pollute environment in case of mineral deposits extraction. 

A. Aituso, Drugs of Natural Origin Economic and Policy Aspects of Discovery, Development, and Marketing, The Pharmaceutical Products Press, New York, 1997, p. 142. 

A number of different glues were utilized on early aircraft. Since these craft were manufactured during the infancy of synthetic polymeric chemistry, all were of natural origin. These glues are still in use today, though not for aerospace bonding. 

The number of clear human epidemiologic studies is small. A total of approximately 50 compounds (c.g., benzene, vinyl chloride) and complex e.xposures (e.g., aluminum production, tobacco smoke) have sufficient data available to permit their classification as human carcinogens. The most potent human carcinogens known, the aflatoxins. are of natural origin. Their presence in food products through infestation by toxin-producing fungi constitute a serious problem in several tropical and subtropical countries. 

Selinene is still another case of unhappy nomenclature. The natural, body is first known as selinene. The regenerated sesquiterpene is termed ortho-tt-selinene, and because the natural, originally named selinene does, not agree with the artificial body, it is now called psewdo-selinene . 

Sulfur oxide emissions enter the atmosphere from a variety of sources, some of human origin, others of natural origin. The main sulfur oxide is sulfur dioxide, or SO,. 

The stereogenic sulfur atom in sulfoxides is usually configurationally stable at room temperature thus, sulfoxides may be chiral based on this property alone1. In fact, there are many examples of optically active sulfoxides of both synthetic and natural origin. This chapter reviews the important methods for obtaining optically active sulfoxides, and discusses some reactions at sulfur which either leave the coordination number at three or increase it to four, generally with preservation of optical activity. It also describes briefly some recent studies on the conformational analysis and chiroptical properties of sulfoxides. 

The stratosphere contains, however, only small amounts--a few tenths of a ppb-of chlorine free radicals of natural origin. They are produced by the decomposition of methyl chloride, CH3Q. The nitrogen oxides (NO and NO2) are more abundant and are produced in the stratosphere by the decomposition of nitrous oxide, N2O. Both CH3CI and N2O are of biological origin these compounds, released at the Earth s surface, are sufficiently stable to reach the stratosphere in significant amounts. 

Polymers are very large organic molecules that are either made synthetically or are of natural origin, and find use as plastics, rubber, fibers, and coatings. Polymers were first produced commercially in 1860 by modification of cellulose from wood or cotton, followed by a fully synthetic product made from phenol and formaldehyde in 1910. 

Humans have used dyes to create color since the dawn of history. Until the mid-nineteenth century, all dyes were of natural origin. Many came from plants, such as indigo, a dark blue dye that was extracted from the leaves of a native East Indian plant. In 1856, the young English chemist William Perkin stumbled upon the first synthetic dye. Perkin was trying to synthesize quinine, a valuable antimalaria dmg. None of his experiments met with success. As he was about to discard the residue from yet another failed reaction, Perkin noticed that it was colored with a purple tinge. He washed the residue with hot alcohol and obtained a purple solution from which strikingly beautiful purple crystals precipitated. Perkin had no idea what the substance was or what reactions had created it, but he immediately saw its potential as a new dye. 

Protective colloids can be divided into synthetic and natural materials. Table 3 classifies the pharmaceutical gums, thickeners, and other hydrophilic polymers according to their origins [72]. Protective colloids of natural origin, such as gelatin, acacia, and tragacanth, have... 

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