Temperate oils

The tropical oil crops, coconut and palm, are the most efficient oil-producing crops, with coconut plantations yielding up to 2 tonnes per hectare of oil and the best performing palm plantations from 5-6 tonnes per hectare. By comparison, oil yields of temperate oil crops are typically of the order of 1-2 tonnes per hectare for the best oil-yielding crops (oilseed rape and sunflower). Clearly, Table 2.1 represents only a small fraction of oil-bearing plant species. Many other seed, fruit and nut oils are extracted for food use, however unless they contain fatty acid profiles or fatty acid derivatives of specific industrial interest, total oil-yield, fatty acid yield and cost of the final oil product tends to limit their use in industrial applications on all but a small or localised scale. 

Activated charcoal provides an additional safety element for dealing with sporadic discharges, e.g. accidental, into river-water of organic substances e.g. mineral oil, tempering oils. 

Quenzine. [Witco] Degreasers, heat treating salts, tempering oils, blackening... 

El-Shattory, Y., Hegazy, S., Soliman, M.M. and Aly, S.M. (1991) Heated fats. Part 3. Biological affect and effect of heating and tempering oils on fatty add composition of liver, heart and serum lipids of rats. Nahrung 35, 1007-1012. 

The 15W40 or 15W50 oils are the most widespread in temperate climates (Western Europe), while the 20W40 or 20W50 oils are used in relatively warm climates (Mediterranean countries. Middle East, South America). The 5W or lOW grades are used in countries having severe winters such as Scandinavia and Canada. 

The flax fiber from the aimual plant IJnum usitatissimum (flax family, Liuaceae) has been used siuce ancient times as the fiber for linen. The plant grows iu temperate, moderately moist climates, for example, iu Belgium, France, Ireland, Italy, and Russia. The plant is also cultivated for its seed, from which linseed oil is produced. A by-product of the seed plant is the tow fiber used iu papermakiug. 

The medium is the binder which provides for the adhesion of pigments. The most important types are the temper media (glue, egg, and gum), the oils, and wax. In addition, for wall painting there is the tme fresco technique, where the pigments are laid down in a fresh, wet plaster preparation layer. Several other media have been used, but much less frequendy, eg, casein temper. In modem paints, a number of synthetic resins are used for this purpose. Contemporary artist paints are often based on acryhc polymers (see Acrylic ester polymers Paints). 

Olefin oligomers are used widely as automotive lubricants. They often are combiaed with some of the organic esters as base fluids ia engine oils, gear oils, and hydrauHc fluids, eg, for equipment intended for operation ia extremely cold climates, and for premium oils, eg, for the service station market ia temperate climates. 

In temperate climates extracts from some plants were found to be excellent preservatives for hides and skins. The hides, with or without hair, were placed in pits in the ground, then covered with alternating layers of bark or leaves and skins. Water was added and later, ie, days or months depending on the thickness of the hide, the hides could be removed, washed, and oiled. The resulting leather is flexible and lasts essentially forever. This procedure was used well into the seventeenth century as the most common method of tanning. In some isolated primitive societies, the method is used in the 1990s. 

Cohimn pressure at the reflux drum is established so as to condense totally the overhead vapor or some fraction thereof. Flash-zone pressure is approximately 69 kPa (10 psia) higher. Crude-oil feed temper-... 

The optimum precipitate is obtained by a more elaborate heal treatment the alloy is solution heat-treated (heated to dissolve the impurity), quenched (cooled fast to room temperature, usually by dropping it into oil or water) and finally tempered or aged for a controlled time and at a controlled temperature (to cause the precipitate to form). 

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