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Accurate assessment of the quantity and chemical type of phosphorus (P) content in processed meat products may have major clinical implications for management of kidney disease patients. We examined 40 lots of cooked ham including 20 without and 20 with P-containing preservatives. Novel spectro-photometrical methods were employed to measure total P and 3 different P subtypes, i.e., water-soluble (inorganic) P including added preservatives and natural P derived from phospholipids and phosphoproteins separately. Total Nitrogen and fat contents were assayed, as well. There was 66% more inorganic P in preserved vs. non-enhanced ham, i.e., 169±36 vs. 102±16 mg/100g (p<0.001), respectively; there were no significant differences in P contents derived from proteins or lipids. The P-to-protein ratio in preserved and non-enhanced ham was 16.1±4.0 and 9.8±0.8 mg/g, respectively (p<0.001). The sum of measured inorganic P and P from phospholipids and phosphoproteins was 91%±4 % of measured total P (207.1±50.7 vs 227.2±54.4 mg/100g, p>0.05), indicating a small portion of unspecified P and/or undermeasurement Novel differential dietary P measurement detects added P-containing preservatives. Processed cooked ham has 66% more measurable inorganic P and 64% higher P-to-protein ratio than non-enhanced product. The contribution of processed food to global dietary phosphorus burden can negatively influence CKD outcome and counteract the efficacy of P-binder medications.

The oscillatory behavior of a -catalyzed/bromomalonic acid/acidicbromate Belousov-Zhabotinsky system in aerated batch conditions has been reinvestigated. An 18-step skeleton mechanism is proposed. Reactions involving oxygen in the aqueous phase as well as reactions involving organic radicals are included in the skeleton mechanism. The numerical treatment of the corresponding differential equations leads to simulated behaviors in satisfactory agreement with the experimental ones.

The paper illustrates integrated physical chemistry-computational lab experiments at the tertiary level on the "classic" Belousov-Zhabotinsky (BZ) oscillating reaction. The complete work was designed for studying the behavior of the Ce4+/Ce3+- and Fe(phen)32+/Fe(phen)33+-catalyzed BZ systems and developing a kinetic model to interpret the experimental data. The students prepared the appropriate reactant mixtures and followed spectrophotometrically the absorbance of Ce4+ and Fe(phen)32+ ions. Then they plot the period of oscillation as a function of the initial concentration of any one of the mixture components observing in particular the difference in the dependence of the oscillation period on the [Ce4+]o and [Fe(phen)32+]o respectively. These differences suggest that the two redox couples catalyze the BZ reaction by different mechanisms. A kinetic mathematical model based on the FKN mechanism for the cerium-catalyzed reaction is presented and discussed. The numerical intergration solutions of the resulting rate equations show that the model accounts satsfactorily for the oscillations of the Ce4+/Ce3+-catalyzed system but fails to reproduce the experimental behavior of the system catalyzed by the couple Fe(phen)32+/Fe(phen)33+. It has been proved that these integrated chemistry-computational lab experiments are a powerful tool in stimulating student interest in physical chemistry and in showing the importance of chemical kinetics in the elucidation of reaction mechanism