Resonance Raman spectra of ozone at two excitation wavelengths (266 and 270 nm) have been measured up to 11 000 cm−1. Band origins have been measured to high accuracy and determined to within a few cm−1. Several bands beyond the dissociation limit have been observed. All prominent bands observed in this work fit to a two-oscillator Darling–Dennison model. An analytical two-dimensional potential energy surface has been constructed based on the new experimental data.

Analysis of weak oscillations in the Hartley absorption system of ozone via the equivalent recurrences in the autocorrelation function is found to reveal a clear temperature effect. Previous classical trajectory studies of unstable nearly periodic orbits associated with these oscillations/recurrences are extended to examine the possibility that strong sensitivity to initial rotational conditions is responsible. Using minimum return distance in phase space as an expedient measure for the stability of the orbits, evidence is found for particular destabilization due to in-plane rotations of the ozone molecule. A model for the recurrence temperature dependence is constructed based on this mechanism, and the implications for comparison of theoretical and experimental recurrence intensities are discussed.

Mesoporous bioactive glass (MBG) is considered as one of the most important materials in the field of bone implants and drug carriers, owing to its superior bioactivity. In previous studies, tri-block surfactants (e.g., F127 and P123) were commonly used as pore-forming agents. However, the use of surfactants may cause serious problems such as micelle aggregation and carbon contamination and thus decrease bioactivity. Therefore, in this study, we demonstrated the synthesis of MBG using acetic acid (HAc) as a pore-forming agent to overcome the disadvantages caused by surfactants. Both untreated and HAc-treated BG powders were synthesized using spray pyrolysis and various characterizations were carried out. The results show that a mesoporous structure was successfully formed and the highest specific surface area of ~230 m2/g with improved bioactivity was reported.

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A new ozone trapping system designed for safe and consistent delivery to a reaction vessel is described. Silica gel is used to trap the ozone because of its known safety advantages over traps that store ozone in liquid form. The new design is free of any liquid baths, such as freon or flammable solvents. A circuit design for monitoring and controlling the ozone partial pressure of 6–25 Torr is also described.