Phosphorus Critical constants

Phosphorus see also Elements critical constants, 6-39 to 58 dielectric constant, 12-45 to 53 electron configuration, 1-18 to 19 heat capacity, 4-135 history, occurrence, uses, 4-1 to 42 ionization energy, 10-203 to 205 isotopes and their properties, 11-56 to 253 magnetic susceptibility, 4-142 to 147 physical properties, 4-133 to 134 thermodynamic properties, 5-1 to 3... 

Macro- and micronutrients should be provided as needed. Soils usually contain sufficient levels of micronutrients, but very often there is a lack of nitrogen and phosphorus. The addition of N and P is particularly important during the initial stages of treatment, in order to stimulate the growth of indigenous bacteria. After the initial development of a critical microbial mass, N and P are constantly recycled due to the lysis of dead microbial cells.9... 

A. Smits and S. C. Bokhorst calculated the value of the constant b of J. D. van der Waals equation. This when taken to represent the size of the molecule becomes 0-00539, at the critical temp. the corresponding value calculated for the phosphorus atom in phosphine is 0-00124 so that there are 0-00539/0-00124=4-33 atoms in the molecule. This is taken to indicate a slight association of the P4-mols. J. J. van Laar calculated for b of J. D. van der Waals equation, 6=0-00140 for a, Va=0-066 and for the valency attraction A, VA—33. M. Trautz calculated 20xl0 8 cm. for the molecular diameter of phosphorus. 

The term d[P j,]/dt is calculated assuming that the concentration of phosphorus in all decomposing litter is 0.16 mmol 1110 . This is based on the 68% retranslocation of P from leaves and fine roots and the average branch, bole, and coarse root P concentrations (Sec. 3.2). Where the sensitivity of the model to P accumulation in the microbial carbon pool is tested, based on data summarized by Gijsman et al. (1996) we use a tissue P concentration for microbes of 6.4 mmol P moG C. In all simulations, it is assumed that soil phosphorus mineralization proceeds with a rate constant of 0.5 year , with phosphorus mineralization proceeding independently of carbon mineralization. This is on the basis of the evidence discussed in Sec. 2.1. Indeed, inflexible soil carbon pool C/P ratios which effectively link phosphorus mineralization rate to the carbon mineralization rate in models such as CENTURY (Parton et al, 1988) have been strongly criticized by some tropical soil chemists (Gijsman et al, 1996). 

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