Phosphorus, abundance production

Fig. 6.3 Conceptual drawing of the distribution of different groups of herbaceous plants in relation to major plant nutrients. Cycles represent the distribution of grasses, herbs, and legumes. Species with mycorrhiza are able to exploit sites low in both nitrogen (N) and phosphorus (P). Highly productive species, such as ruderal plants, need conditions abundant in N and P. 

Phosphorus is abundant on Earth, both as an element (the llth-most abundant atom in Earth s crust) and as phosphate. Meteorites hold a variety of phosphate-containing minerals and some phosphide minerals.10 Scientists at the University of Arizona have recently suggested that Fe3P, the mineral schreibersite, leads to the formation of phosphate and phosphite when corroded in water. Although phosphorylation of alcohols was not demonstrated, mechanistic considerations suggest that it should be possible. It is noteworthy that a clear prebiotic pathway for the chemical incorporation of phosphate into RNA or DNA has not been found. No nucleosides (nucleobases joined to sugars) have been reported from meteorites. Nor has evidence been found in any meteorite of the presence of nucleosides or nucleotides (nucleosides attached to phosphates). That suggests that nucleic acids were first formed as products of metabolism. 

Cellulose. Fiber components differ in their ability to bind to bile (41), the primary route of excretion of manganese (9). Cellulose, the most abundant natural fiber, has been studied for its potential effects on bile and lipid metabolism (42). It is naturally present in high fiber diets and is also commonly added to many commercially-produced food products. Previous studies have shown cellulose to decrease intestinal uptake of a variety of minerals, including zinc, phosphorus, calcium, magnesium, and iron (32,43,44). In many cases, however, the effect of cellulose has not been considered to be anti-nutritional (32). It has been generally believed that cellulose has a lower binding affinity for minerals than other constituents of dietary fiber (33,45). 

The abundance and low cost of light alkanes have generated in recent years considerable interest in their oxidative catalytic conversion to olefins, oxygenates and nitriles in the petroleum and petrochemical industries [1-4]. Rough estimates place the annual worth of products that have undergone a catalytic oxidation step at 20-40 billion worldwide [4]. Among these, the 14-electron selective oxidation of -butane to maleic anhydride (2,5-furandione) on vanadium-phosphorus-oxide (VPO) catalysts is one of the most fascinating and unique catalytic processes [4,5] ... 

Although nitrogen is the element primarily controlling eutrophication in estuaries and coastal seas, and phosphorus is the element primarily controlling eutrophication in lakes, other elements can have a major influence on the community structure of aquatic ecosystems and can influence the nature of the response to eutrophication. A key element in this regard is silica (silicon), an element required by diatoms. The availability of silica in a water body has little or no influence on the overall rate of primary production, but when silica is abundant, diatoms are one of the major components of the phytoplankton. When silica is in low supply other classes of algae dominate the phytoplankton composition. 

Radioactive isotopes for tracer studies may be prepared artificially from nonradioactive elements by bombarding them with suitable nuclear particles produced in a cyclotron or a nuclear reactor. The discovery of this effect was made in 1934 by the French physicists Irene Joliot-Curie (1897-1956) and her husband Frederic Joliot-Curie (1900-1958). They were studying the effect of bombarding light elements such as aluminum with alpha (a) particles, which are beams of helium nuclei, fHe. They noticed that, after the bombardment had ceased, a new form of radiation continued to be emitted, and they concluded that a new isotope had been formed. In the case of the bombardment of ordinary aluminum, HAl, with a particles, the product is an isotopic form of phosphorus, ifP, the most abundant isotope of phosphorus being f P. The process is... 

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