Sources and Production

Sources and Production Potassium is highly reactive and does not occur in nature as a free metal. The abundance of potassium in the 16 km-thick Earths crust - mainly in silicates (feldspars, micas) - is 25.9 g kg k In the frequency list of the elements, potassium occupies seventh place. Its abundance in sea vater is almost as great, due to the veathering of potassium-containing minerals. After veathering of the rocks, potassium is bound by the calcium zeolites of the soils, and only part of it reaches the sea (0.38 g sea water). 

In workable deposits, potassium is found mainly in the form of potassium chloride and sulfate. Such salt deposits were formed by crystallization and/or evaporation of marine regions during various stages of the Earth s development. The largest potassium chloride deposit known is in Saskatchewan (Canada), while the largest deposit of carnallite (KCl MgCl2n6H20) is in Solikamsk (Russia). 

Justus von Liebig (1842) spread the knowledge that potassium is one of the important plant nutrition elements. In 1861, Adolph frank started the first plant using the process he had developed for producing from carnallite - a potassium salt that could be employed as a fertilizer. When Alsace was returned to franco at the end of World War I, the potash works become French property, so that Germany lost her monopoly in potash. Potash production in Spain began in 1926 in Catalonia. In Sicily (Italy) kainite deposits were used for potassium sulfate production. In Russia, potassium production began 1931 in the northern Urals. In 1939, the Soviet Union took over potassium 

potash ores are treated by three basic processes leaching-crystallization, flotation, and electrostatic treatment. Gravity separation is of minor importance because of the small density differences between the salt minerals (Schultz etal. 2002). 

Potash salt deposits were formed by the evaporation of sea water. Their composition is often affected by secondary changes in the primary mineral deposits. More than 40 salt minerals are presently known, which contain some or all of the small number of cations Na, K , Mg , and Ca , the anions Cr and S04 and also occasionally Fe and BOj. The more important salt minerals are halite, anhydrate, sylvite, carnallite, kieserite, polyhalite, langbeinite, and kainite. 

In developing countries, gold mining activities increased substantially in the late 1960s following the end of the 1944 Breton Woods agreement which limited the price of gold to US 35 per troy ounce. The price rose 

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The term origin is often used synonymously with both source and production centre, but is less specific than either. 

Besides these external processes, formation of ROS may also take place intrac-ellularly. Photooxidative stress, including UVB, stimulates various cellular processes leading to the production of superoxide radicals and hydrogen peroxide, as well as singlet-oxygen and hydroxyl radicals. The sources and production sites of ROS are mainly related to photosynthetic activities such as the pseudocyclic photophosphorylation and the Mehler reaction, which stimulate the accumulation of hydrogen peroxide (Asada 1994 Elstner 1990). 

Short-term tests applied to small samples can add useful information about the variability of the source and product water that could effectively supplement analytical data. 

The major objective of this chapter is to examine and synthesize the published literature with respect to sources and production of terrestrially derived DOC, its relationship with dissolved organic nitrogen (DON), and the mechanistic controls on their export from terrestrial ecosystems to surface waters. With the exception of wet precipitation (which is ranked by continental landmass), we have classified data for throughfall and soil solution under biome type. Where possible, we have shown mean and standard deviations of some biomes to illustrate the amount of variance within and between biomes. Relationships between DOC and DON are illustrated using only those studies that report both DOC and DON concentration. Because most research on DOC and DON has been accomplished in relatively undisturbed areas, particularly forests, this chapter concentrates on the aspect of diffuse-source allochthonous inputs to surface waters and not point-source inputs from urban and agricultural areas. Recent work by Westerhoff and Anning (2000), however, indicates that more research on effluent or point-source DOC as a contributor to riverine allochthonous inputs may be... 

Chinese sourcing and production functions should also be integrated into the company s global setup. This may require rethinking both networks, but defining an optimal global footprint from the outset helps avoid internal battles for capacity utilization as Chinese-produced sales cannibalize their western counterparts. 

Fuels See Coal Energy Sources and Production Fire, Fuels, Powerplants Gasoline Petroleum. 

Alkaline Earth Metals Molybdenum Energy Sources and Production... 

Clough, P. (2001) Sources and production of specialty oils containing GLA and stearidonic acid. Lipid Technol., 13, 9-12. 

Food materials, including fish, contain the precursors to these bioactive peptides, which can be formed in vitro or in vivo by enzymatic hydrolysis (Korhonen and Pihlanto 2003). During the past decade, a number of studies have reported on the many physiological properties of these bioactive peptides. The aim of this review is to describe the production of novel peptides derived from marine protein hydrolysates, elucidating the underlying mechanisms of physiological and biofunctional activity that are particular to individual bioactive peptides. The general sources and production of protein hydrolysates will be discussed, followed by a discussion of the nutraceutical properties of protein hydrolysates and their associated bioactive peptides. 

The diversity and complexity deepened during the 1970s and 1980s as many companies moved downstream into specialty chemicals and other areas. Such an approach was essential for them to remain cost competitive. It allowed them to capture the benefits of physical integration - namely, a secure supply of feedstocks, convenient outlets for intermediate products, minimal logistics costs, and the optimal use of byproducts. Integration also helped to reduce problems in an environment where many raw material sources and product markets were controlled by a small number of players. 

Fish oils are a byproduct of the production of fish meal. Both commodities are subject to price flucmations that are only indirectly related. The meal has been historically used for terrestrial animal feedsmffs. The production process can be condensed to apply to two basic functions take fish or fish waste, cook it, and squeeze it (Figure 2). Subsequent steps are varied for each commodity, but they essentially are well described by Young (20), whereas the desirable properties of fish meal are concisely described by Bimbo and Crowther (21). Similar summaries, especially on sources and production, are provided by various chapter authors in a book on pelagic fish (22), because most fish caught for meal and oil are pelagic (migratory) and subject to seasonal exploitation. The principal competition to fish meal is soybean meal and other oilseed meals (23). 

Metals are found in almost all excipients. The types of metals and levels present in excipients can vary significantly depending on the excipient type, source, and production process used to extract or produce the excipient. 

Wyllie, P.J., Wolf, M.B., and van der Laan, S.R., 1997. Conditions for formation of tonalites and trond-hjemites magmatic sources and products. In De Wit, M. and Ashwal, L.D. (eds) Greenstone Belts. Oxford University Press, Oxford, pp. 256-66. 

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