This study presents a non-invasive approach to monitoring post-harvest fruit quality by applying CO₂ laser photoacoustic spectroscopy (CO₂LPAS) to study the respiration of “Conference” pears from local and commercially stored (supermarket) sources. Concentrations of ethylene (C₂H₄), ethanol (C₂H₆O), and ammonia (NH₃) were continuously monitored under shelf-life conditions. Our results reveal that ethylene emission peaks earlier in supermarket pears, likely due to post-harvest treatments, while ethanol accumulates over time, indicating fermentation-related deterioration. Significantly, ammonia levels increased during the late stages of senescence, suggesting its potential role as a novel biomarker for fruit degradation. The application of CO₂LPAS enabled highly sensitive, real-time detection of trace gases without damaging the fruit, offering a powerful alternative to traditional monitoring methods. Additionally, artificial intelligence (AI) models, particularly convolutional neural networks (CNNs), were explored to enhance data interpretation, enabling early detection of ripening and spoilage patterns through volatile compound profiling. This study advances our understanding of post-harvest physiological processes and proposes new strategies for improving storage and distribution practices for climacteric fruits.

A new method for the synthesis and deposition of tungsten oxide nanopowders directly on the surface of a carbon-fiber-reinforced polymer composite (CFRP) is presented. The CFRP was chosen because this material has very good thermal and mechanical properties and chemical resistance. Also, CFRPs have low melting points and are transparent under ionized radiation. The synthesis is based on the direct interaction between high-power-density microwaves and metallic wires to generate a high-temperature plasma in an oxygen-containing atmosphere, which afterward condenses as metallic oxide nanoparticles on the CFRP. During microwave discharge, the value of the electronic temperature of the plasma, estimated from Boltzmann plots, reached up to 4 eV, and tungsten oxide crystals with a size between 5 nm and 100 nm were obtained. Transmission electron microscopy (TEM) analysis of the tungsten oxide nanoparticles showed they were single crystals without any extended defects. Scanning electron microscopy (SEM) analysis showed that the surface of the CFRP sample does not degrade during microwave plasma deposition. The X-ray attenuation of CFRP samples covered with tungsten oxide nanopowder layers of 2 µm and 21 µm thickness was measured. The X-ray attenuation analysis indicated that the thin film with 2 µm thickness attenuated 10% of the photon flux with 20 to 29 KeV of energy, while the sample with 21 µm thickness attenuated 60% of the photon flux.

The central collision between a neon atom and a dodecahedrane cage has been investigated within the framework of ab initio Hartree-Fock molecular dynamics simulations for various initial velocities of the incident atom. Four scenarios regarding the interaction’s outcome have been identified. A reaction channel involving the encapsulation of the projectile inside the molecular cage has been studied for a simulation time of 4.8 ps. The analysis is focused on: the rate of energy exchange between Ne and C₂₀H₂₀, the mechanical oscillation frequencies of the atom and the cage, and also, on the frequency with which the dipole moment changes. The results suggest that inside the molecular cage, neon is a stable atomic vibrator, which oscillates with the highest peak frequency of 16 THz. Furthermore, the same frequency characterizes the dipole moment oscillation, suggesting a strong coupling between the atom and the cage, making the endohedral system suitable for a wide range of applications in nano-electronics.

Ab initio simulations reveal how fullerane vibrational modes induce high-pressure hydrogen states, offering a new route toward metallic hydrogen.

The encapsulation of hydrogen within fullerene/fullerane cages offers a promising avenue for studying high pressure hydrogen dynamics. Through ab initio molecular dynamics simulations, we investigate the behavior of a system consisting of hydrogen atoms enclosed in a \ch{C20H20} dodecahedrane. Our findings reveal significant structural and dynamical changes as the cage undergoes compression, corresponding to radial symmetric vibration. We analyze geometric, energetic, and thermodynamic parameters, highlighting correlations and observing behavior analogous to high pressure phases of hydrogen. Notably, our study bridges the gap between theory and experiment by proposing a novel approach to achieving high pressures and temperatures experimentally. These results not only contribute to the understanding of hydrogen behavior under extreme conditions but also hold implications for the quest to attain metallic hydrogen - a milestone in materials science with potential applications in various fields.