Phosphorus deposition

A.STM B656, Standard Guide for Autocatalytic Nickel—Phosphorus Deposition on Metals for Engineering Uses American Society for Testing and Materials, Philadelphia, Pa., 1991. 

Despite its relatively late discovery, phosphorus is the eleventh most abundant element in Earth s crustal rock. It has been estimated that world reserves of phosphate rock are sufficient to last for several hundred years. Virtually all phosphorus deposits contain apatite, whose general formula is Caj (P04)3 X, where X — OH, or Cl. Fluoroapatite is the least soluble, hence most abundant, of the three apatite minerals. Phosphorus Is found in aqueous systems as HPOq and H2 PO4 ions. In biological organisms, phosphorus is a component of nucleic acids and energy-shuttling molecules such as ATP. 

Nickel phosphorus deposits, 9 702-708 corrosion protection, 9 709 Nickel-phosphorus plating, 9 821-822 Nickel plating, 9 764 17 99, 108 baths, 9 821... 

Phosphorus deposition, 9 692-693. See also Nickel phosphorus (Ni-P) deposits... 

Table II shows the effects of varying dietary levels of zinc on weight gains and on bone calcium and phosphorus levels of young rats at the end of a 4-week experiment. Increases in dietary zinc were associated with significant linear decreases in bone calcium and phosphorus deposition. The bones taken from animals at the time of sacrifice and used for the mineral analyses were very soft in nature and could be easily squeezed with the fingers.

Alkaline phosphatase Hypophosphatasia due to accumulation of inhibitors of mineralization such as pyrophosphate, and inability to raise phosphorus levels at the site of calcium-phosphorus deposition into hydroxyapatite... 

Treat the unreacted white phosphorus deposit remaining on the walls of the reaction flask with bromine water. 

Tiny pieces of white phosphorus deposited on filter paper burst into flame on contact with air. That s why white phosphorus is never found free in nature. Phosphorus is an essential element in living systems for example, phosphate groups occur regularly along strands of DNA. 

In freshwater ecosystems, the amounts of phosphorus introduced to sediments are estimated to be of the order of 1 Tg P y while the amounts released from sediments annually are estimated to be less than 1 Tg P (Pierrou, 1976). Emery et al. (1955) calculated that the amount of phosphorus deposited in ocean sediments is 13 Tg P y. The amount of phosphorus released from ocean sediments is unknown but is probably relatively small, as the reducing conditions (lack of oxygen) required occur relatively rarely in the ocean. The uptake of phosphorus by phytoplankton in the ocean has been variously calculated as 1300 Tg P y (Emery et al., 1955) and 990 Tg P y (Stumm, 1973). A similar estimate, about 1000 Tg P y, can be made for the amount of phosphorus deposited in oceanic detritus (Pierrou, 1976). 

A and B are the imaginary melting-points of pure Pa and P. In equilibrium with the liquid solutions AC there exist the solid solutions Ad and in equilibrium with the liquid solutions BC, there exist the solid solutions Below the eutectic horizontal de lies the metastable equilibrium diagram for the solid solutions ( 2 i 3)> known as white phosphorus, in contact with liquid solutions, 12 x1. LxLi is the curve of internal equilibrium in molten phosphorus. At m, molten phosphorus deposits (if supercooling is excluded) the solid solution n (violet phosphorus). The temperature corresponding to m is about 590 (p. 62). 

The poisoning of a Pt/Pd catalyst by phosphorus deposition in an application for the oxidation of solvent hydrocarbons in the exhaust from a web offset press was reported by Lester and Summers. ... 

Figure 6. The first order dependence of lead and phosphorus deposition...

Results are shown in Table 1 and Figs. 5 and 6, in which four of die Ford test oils are listed. (Oil X, which contained no phosphorus, was not submitted for PEI evaluation by Ford but has value in die comparisons made.) The figures show the additives present as well as the level of phosphorus deposits and die NOx emissions for each oil. 

Preliminary sensitivity analysis suggests that the model is sensitive to changes in phosphorus dust deposition rates and dissolved organic matter loss. Model runs simulated the impact of increasing (+0.005 g P/m /year) and decreasing (-0.005 g P/m /year) dust phosphorus (loose dust phosphorus deposition of... 

Fig. 15.8. Simulated change of plant production (a), soil carbon (b), and organic soil phosphorus (c) resulting from altered dust phosphorus deposition rates.

Ward BC, Webster TJ. The effect of nanotopography on calcium and phosphorus deposition on metallic materials in vitro. Biomaterials 2006 27 3064-74. 

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