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The free fatty acid (FFA) content together with the lipase activity control can be considered as useful indexes of good quality and correct storage of food, especially for milk. The quantitative analysis of FFA in different kinds of milk has been performed by a potentiometric method, using a new extractive methodology outlined herein. The lipase activity has been controlled by a sensitive calorimetric method, previously validated by us, based on the direct measure of the heat quantity involved in the enzymatic reaction. In order to verify the milk quality after the healing treatments and/or during the shelf life, the behaviours of FFA content and of lipase activity have been outlined in function of storage time and pH variations on different typologies of milk. The FFA content in sample of fresh pasteurised milk was found to be quite high after the 5th/6th day of storage at +4 °C, meanwhile the pH values were always constant and only after the 9th day begun to decrease. At the same time the lipase activity, directly measured, was found to be appreciable after the 6th day of storage, giving an exothermic answer at the calorimeter, similar to that of a milk sample where only three international units of standard lipase were added. [Copyright &y& Elsevier]

The coordination chemistry of dioxouranium(VI) with organic ligands may represent an useful model to describe the migration of radionuclides in natural fluids. A new dioxouranium(VI) ternary complex of formula Na4(UO2)2(OH)4(C2O4)2 was precipitated at pH≅8. It was characterized by elemental analysis, ICP and IR spectroscopy, thermogravimetry (TG) and coupled TG–IR evolved gas analysis. Potentiometric measurements in the solution suggest that the equilibrium shifts from the prevalence of the (UO2)2(OH)2(C2O4)46− complex to the [(UO2)2(OH)4(C2O4)2]4− complex before the formation of a solid phase. [Copyright &y& Elsevier]

Abstract: The analytical applications of the evolved gas analysis (EGA) performed by mass spectrometry, for the period extending from 2001 to 2004, are collected in this review. By this technique, the nature of volatile products released by a substance subjected to a controlled temperature program is on-line determined, with the possibility to prove a supposed reaction, either under isothermal or under heating conditions. [Copyright &y& Elsevier]

Abstract: The analytical applications of the evolved gas analysis (EGA) performed by infrared spectroscopy, for the period extending from 2001 to 2004, are collected in this review. By this technique, the nature of volatile products released by a substance subjected to a controlled temperature program are on-line determined, with the possibility to prove a supposed reaction, either under isothermal or under heating conditions. [Copyright &y& Elsevier]