EPR structural study on hydrothermally aged yttria-doped tetragonal zirconia polycrystals

EPR measurements on yttria-doped tetragonal zirconia polycrystals (Y-TZP) were performed in order to study the modifications of the structure of the material following hydrothermal treatments. By X-ray irradiation of the samples, the structural defects near the oxygen vacancies were magnetically activated by electron trapping. Y₂O₃ aggregates were identified by EPR signals of defects of F⁺ type, coordinated with yttrium ions, and defects such as Y²⁺ (4d¹) in four-fold coordination, randomly tetragonally distorted. The analysis of these defect sites, used as local probes, supports the existence of structural modification of the material and the formation of -Y(OH)₃ clusters.     

New Routes and Airport Connectivity

This paper shows how module identification techniques can help airports evaluate the impact of new routes on their network connectivity. Although only carriers can choose whether to open a new route, this research is also of interest to airports and regional governments, who can offer incentives for new connections to desirable destinations. The analysis employs simulated annealing to verify the existence of highly interconnected subsystems, or modules, within the European aviation network. A module is a group of airports with very strong internal links in terms of exchanged seats, but weak connections to the rest of the network. From the standpoint of improving connectivity, we expect that new routes towards large airports belonging to other modules are the most desirable. We also find that the lower the interchange between the modules to be connected, the higher the connectivity gain. We test this hypothesis on all 467 European airports with at least one scheduled flight in autumn 2007.     

Smoked tuna, sliced and vacuum packed, a relatively new product

Summary The possibility of storing vacuum packed, smoked and sliced tuna fish was studied. The microbiological and chemical analyses demonstrated that hygienic conditions and organoleptic properties remain unaltered after storage at 5° C for 60 days.

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Geräucherter Thunfisch, in Scheiben geschnitten und vakuumverpackt, ein relativ neues Produkt

Zusammenfassung Es wurde die Möglichkeit studiert, den geräucherten Thunfisch vakuumverpackt aufzubewahren. Die anschließend durchgeführten mikrobiologischen, chemischen und sensorischen Analysen bestätigten, daß die hygienischen Bedingungen und die Eigenschaften des Produktes nach einer Aufbewahrungszeit von 60 Tagen bei 5°C unverändert erhalten bleiben.

     

Characterisation of a lard cured with spices and aromatic herbs

The study considered the proximate composition, pH, free acidity, MDA and peroxide values of a cured and ripened lard covered with spices and aromatic herbs, these latter parameters, due to lipolytic endoenzymatic phenomena, tended to increase until the end of the salting period. Throughout the production phases the bacterial load was very low. The final vacuum-packed product had a shelf-life of about 90 days and its fatty acid and cholesterol composition was typical of lard. A GC/MS study of the spices/herbs in the lard highlighted which components came from the spices/aromatic herbs and which came from phenomena due to lipolytic endoenzymatic processes.