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The present work reports experimental results concerning the specific isobaric heat capacity of pure water at elevated pressure. Experiments were performed using a Tian–Calvet differential scanning calorimeter (Setaram Model BT2.15), at temperatures ranging from 298.15 to 465.65 K and at a constant pressure of 4.0 MPa. The aim of this study is to compare the new experimental results with values predicted by the IAPWS-95 formulation, which is generally accepted as reliable by the scientific community despite the fact that, in this formulation, nearly all the data for the isobaric heat capacity of water are based on measurements of Sirota’s group in the former Soviet Union in the period from 1956 to 1970. The present calorimetric results for the specific heat capacity of pure water were found to be substantially in disagreement with the values obtained using the IAPWS-95 formulation, especially at high temperatures, where the differences are greater than 20%. Additional studies are therefore warranted in order to confirm this discrepancy.

The effects of ultraviolet (254 nm) radiation on a hydrated gelatin-glucose matrix were investigated for the development of a physiologically thermostable substrate for potential use in cell scaffold production. Experiments conducted with a differential scanning calorimeter indicate that ultraviolet irradiation of gelatin-glucose hydrogels dramatically increases thermal stability such that no melting is observed at temperatures of at least 90°C. The addition of glucose significantly increases the yield of cross-linked product, suggesting that glucose has a role in cross-link formation. Comparisons of lyophilized samples using scanning electron microscopy show that irradiated materials have visibly different densities.

Elastic stress concentration factors (SCFs) for internally pressurized thick cylindrical vessels with oblique circular crossholes are reported. Results of finite-element analyses for two wall ratios (k equal to 2.25 and 4.5) and a range of crosshole ratios (d from 0.1 to 0.5) show that SCFs sharply increase with the inclination α of the crosshole axis. These findings are consistent with earlier empirical design guidelines based on experimental investigations.

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