Phosphorus bound

Nephro-Calci 1,500 Approximately 39 mg phosphorus bound per 1 g calcium... 

Limited quantitative and qualitative evidence of the metabolic fate of white phosphorus after acute oral exposure was located. In an acute oral study in rats with 32P-labeled white phosphorus, Lee et al. (1975) determined that urinary and fecal elimination routes respectively accounted for 17.1% and 2%, 34.5% and 16.6%, and 46.7% and 33.0% of the administered dose at 4 hours, 1 day, and 5 days post-dosing, respectively. White phosphorus is insoluble in water, and about 96% of the phosphorus bound in urine is inorganic phosphate (Latner 1975). Based on this, it is reasonable to conclude that -20% of... 

One very important additional concurrent enzyme process has been developed by Alko and Dorr-Oliver (28). This is the steeping of corn with phytase in combination with a T. reesii cellulase rich in side activities. (This enzyme combination was originally developed under the Econase 434 name for use in pig feeds the breakdown of phvtate by phytase released the phosphorus bound by the phytate. This amounts to 50% of the phosphate in corn, for example.) Anyone working with Corn... 

Figure 4 A polyhedral view of the structure of [ Cu2(tppz)(H20) (Mo50i5)(03PQH5)2] 2.5H20(1 2.5H20). Only the phosphorus-bound carbon atoms of the phenyl groups are shown. The copper sites are shown as dark spheres.

The carbethoxy tertiary phosphine Bu2P(CH2) C02Et (n — 1) forms an octahedral, cationic rhodium(III) complex (31), in which the carbonyl group coordinates to rhodium. Homologous ligands ( = 2, 3) from four-coordinate rhodium(II) complexes in which the ligands are only phosphorus bound.275... 

The high asymmetric inductions that can be attained in these reductions are above all to be attributed to steric interaetions of the substrate with the phosphorus-bound phenyl groups of the [Ru-f/fj-BINAP] complex R)-S (Scheme 5). It can be assumed that hydride, being the smallest ligand, coordinates cis to both phosphine ligands. The P-bound phenyl groups occupy equatorial (parallel to the substrate coordination plane) and axial positions (perpendicular to the substrate coordination plane) with respect to the metal-ligand cycle. The skewed BINAP skeleton requires the equatorial phenyl substituents to protrude directly into two of four coordination quadrants that are accessible to the substrate. 

An understanding of the rates of exchange of phosphorus-bound hydrogen is necessary for treatment of the oxidation reactions. Qualitative examination showed extensive exchange. Measurements of the rates of exchange of tritium-... 

Hence it has been concluded that the rate-determining step involves removal of the two phosphorus-bound protons. The energy of activation (24 kcal.mole ) decreases with increasing alkalinity, probably due only to a salt effect. The decomposition has also been examined in the presence of nickel and cobalt, which apparently introduce heterogeneous catalysis . 

O-Sn-O-Sn-O- links face each other so as to allow for the formation of a series of inter-chain Sn... Cl interactions the two independent inter-chain Sn... Cl separations are 3.316(1) A and 3.376(1) A. This arrangement places the phosphorus-bound phenyl groups in close proximity to tin atoms belonging to neighboring double chains and hence, the formation of Sn... itt interactions. Two views of the resultant two-dimensional array are shown in Figure 3.9.16. 

Calcium carbonate (40% elemental calcium) Turns Oscal-500 Caltrate 600 Nephro-Calci LiquiCal CalciChew 500, 750, 1000, 1250 1250 1500 1500 1200 1250 200, 300, 400, 500 500 600 600 480 500 0.5-1 g (elemental calcium) three times a day with meals First-line agent dissolution characteristics and phosphate binding affect may vary from product to product try to limit daily intake of elemental calcium to 1500 mg/day Approximately 39 mg phosphorus bound per 1 g calcium carbonate... 

The number of terminal oxygen atoms, one, is exactly the same in all three acids, so that, according to (a), no great differences in acidity are expected. Since the electronegativities of P and H are almost the same, there is no tendency for the phosphorus-bound H to ionize, nor to influence the ionization of the oxygen-bound H s. 

Phosphorus in mineral form is bound in phosphates (Ca, Mg, Fe, Al) or in the soil colloidal complex in the form of phosphoric acid amides. Phosphorus bound to organic substances is also of importance. 

The year has been largely one of consolidation, with emphasis on the synthesis, structure, and properties of phosphoranes containing small (four- and five-membered) rings, especially the relatively stable compounds afforded by bi- and tri-cyclic structures. A new departure, however, has led to the first reports of five-co-ordinate phosphorus bound to transition-metal complexes vide infra) and these novel compounds may be the precursors of a new wave of chemistry in this area. 

Another example of five-co-ordinate phosphorus bound to a transition metal is provided by the reaction of (112) with (113) to form the spirophosphorane (114) in 91 % yield. The n.m.r. shift at + 67 p.p.m. is very broad (1100 Hz at half height) because of coupling with the manganese nucleus (spin 5/2), but n.m.r. and i.r. data serve to substantiate the structure as five-co-ordinate. 

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