Testing approach to new fibre-reinforced UHTC materials in the C3HARME project

In space applications, very high temperatures are often a driving environmental condition for certain technologies. This is especially true for the engines of rockets and for re-entry systems where thermal protection is vital. With current state-of-the-art systems of both types, there are in some cases materials used which are simply consumed because temperatures are so high, there is no choice of a material able to withstand the conditions. In order to overcome these restraints, Ultra-high-temperature ceramics (UHTC) provide an option in terms of the pure temperature capability of the material. However, bulk UHTC materials so far suffered from the problem of rather low mechanical properties and especially size limitations due to thermal shock sensitivity. If this situation could be improved by introducing a fibre reinforcement and combining the advantages of UHTC with the robustness of Ceramic Matrix Composites (CMC), the resulting UHTCMC materials could open up a whole new world of possibilities for new designs and flight regimes of the systems mentioned. The C3HARME project aims at exactly that. The goal is to develop new fibre-reinforced UHTC types and to significantly improve the maturity of them to a level of TRL 5-6. In order to do so, the thermo-mechanical characterization of samples and components is of great importance. A multitude of different tests are done to get the full data set of all the relevant properties from room temperature up to very high temperatures as they are encountered in the application scenario. The talk will give an overview about the characterization strategy and the individual tests and facilities applied with some of the results already obtained

Aerodynamic study of airframe-engine integration of a supersonic business jet

An increasing number of institutions and companies is recently showing increasing interest in supersonic and hypersonic flight with particular focus on sub-orbital flight and high-speed point-to-point transportation. In this scenario, the University of Naples “Federico II” is currently studying advanced concepts of supersonic/hypersonic aircraft and suitable high-speed propulsion system integration for efficient travel in the Mach 4-5 speed range. Within this framework, a collaboration is in progress with the SME Blue Engineering. In the present work a study is undertaken to investigate the performances along with aerodynamic design of the supersonic intake for the turboramjet engines and the engine-airframe integration for a Mach 4 supersonic business jet. Firstly, attention is focused on directional stability and trimmability enhancement acting on aircraft configuration. The following section is dedicated to the aerodynamic design of a high-efficiency intake adapted to different flight conditions. To conclude, the last section addresses the sensitive issue of airframe-engine integration. The configuration analysis has been carried out with the quick and low-cost software Missile DATCOM, well suited for aircraft preliminary design. For the supersonic intake aerodynamic design and the airframe-engine integration analysis, the commercial Navier-Stokes solver Siemens STAR CCM+ has been used. An improved configuration has been proposed, actioning on vertical tail and wing for the directional stability enhancement, while the trim conditions have been improved using a canard. As for the supersonic intake aerodynamic design, the choice fell on mixed-compression variable-geometry. In particular, a total spike forward translation of 0.65 m guarantees adaptive operations along the supersonic trajectory. In addition, the choice of mixed-compression configuration ensured high efficiency values thanks to the multiple shock waves’ reflection in the supersonic diffuser. For what concerns the engine-airframe integration, the engine location above the wing has been shown to be not suitable due to the strong aerodynamic interference that reflects in a completely off-design intake functioning. Therefore, the configuration has been upgraded integrating the engine with the wing avoiding the issues experienced in the previous cas

Presence of endogenous prednisolone in human urine

The possibility of an endogenous presence of the glucocorticoid prednisolone has already been demonstrated in bovine and horse urine, with the aim of clarifying its origin in this matrix, which is used by official agencies for the control of illicit treatments. From this point of view, the endogenous nature of prednisolone could be a major topic in doping control of both amateur and professional human athletes. A study was therefore made on 34 human volunteers (13 males and 21 females; aged 22\u201362) to detect the presence of prednisolone in their urine by HPLC\u2013MS3. One of the volunteers underwent vernal allergy treatment with betamethasone for two subsequent years. An investigation was carried out with the aim of verifying if the suppression, and the circadian rhythm, of cortisol urinary levels could also apply to prednisolone. The results of the study show that prednisolone was present in the urine of all 34 volunteers, with a concentration very close to 100-times lower that of cortisol, with no dependence on gender. The same ratio (1/100) was observed in the prednisolone and cortisol levels detected during the 24 h together with the suppression of prednisolone by betamethasone treatment. These data demonstrate the endogenous nature of low concentrations of prednisolone in human urine, and motivate further studies about the biosynthetic pathways of this corticosteroid and its relationship with stress in humans, as already described in cows

Investigation of the presence of endogenous prednisolone in equine urine by high-performance liquid chromatography mass spectrometry and high-resolution mass spectrometry

RATIONALE: After the detection of low concentrations of prednisolone in racehorse urine samples collected at Italian racetracks, a study was initiated to investigate the accuracy of the analytical protocol used and the possible endogenous origin of detected prednisolone. METHODS: Multiple reaction monitoring (MRM) MS2 acquisition with a triple quadrupole (n = 780) and full scan MS2 and MS3 (n = 180) acquisition with a linear ion trap were checked. As a further confirmation, ten urine samples were analysed by high-resolution mass spectrometry (HRMS). RESULTS: The study showed the difficulty of identifying prednisolone, probably due to interfering compounds with the same molecular weight (360 Da) present in the matrix. The characteristic transitions for prednisolone were identified, both in MS2 and MS3, as the ions 187 and 280; the ion 295 was also used for identification. The concentrations detected with the triple quadrupole and the linear ion trap were not statistically different. The exact mass of prednisolone formiate (the adduct acting as a molecular ion) was identified by HRMS. CONCLUSIONS: The very high frequency of prednisolone detection in the samples (78.5%), the low concentration of this steroid and, importantly, the narrow range of the 95% confidence limits (0.97\u20131.05 in MS2 mode and 0.88\u20131.04 in MS3 mode), could represent evidence that its presence is endogenous. In the light of these results, this hypothesis seems the most probable, even if further studies are required to confirm it. Furthermore, a microbiological origin (i.e. fermentation of cortisol after sample collection) could not be disregarded