Arylazopyrazoles are an emerging class of photoswitches with redshifted switching wavelength, high photostationary states, long thermalh alf-lives and facile synthetic access. Understanding pathways for as imple modulation of the thermalh alf-lives,w hile keepingo ther parameters of interest constant,i sa ni mportanta spectf or out-of-equilibrium systems design anda pplications. Here, it is demonstrated that the thermalh alf-life of aw ater-solubleP EG-tethered arylazo-bis(o-methylated)pyrazole (AAP) can be tuned by more than five orderso fm agnitude using simple pH adjustment, which is beyond the tunability of azobenzenes. The mechanism of thermalr elaxation is investigated by thorough spec-troscopic analyses and density functional theory (DFT) calculations.F inally,t he concepts of at unable half-life are transferred from the molecular scale to the materials cale. Based on the photochromic characteristics of E-a nd Z-AAP,t ransient information storage is showcased in form of light-written patterns inside films cast from different pH, which in turn leads to different times of storage. With respect to prospective precisely tunable materials and time-programmed outof-equilibrium systems, an externally tunable half-life is likely advantageous over changing the entire system by the replacementoft he photoswitch.

Molecular dynamics simulation using COMPASS force field has been employed to understand the dynamics of water diffusion and structuring in silicalite-1 and Na-ZSM-5 (Si/Al = 95 and 191) samples at three different temperatures, 297, 354, and 393 K, at a water loading of 8 molecules per unit cell, in canonical ensemble. Diffusion coefficients were significantly reduced upon the introduction of aluminum atoms into the framework, together with charge balancing cations placed in their vicinity, since the ion-dipole interactions dominant in ZSM-5 samples are stronger than the H-bond interactions in silicalite-1. The activation energy of diffusion increased with decreasing Si/Al ratio. In the silicalite-1 and ZSM-5 samples, straight channels were observed to be preferred than the sinusoidal ones and the channel preference was not observed to be a strong function of either temperature or the Si/Al ratio. The ordered structures of the water molecules, forming clusters in the channels of silicalite-1 at low temperature was observed to be broken to some extent by increased temperatures, and decreased Si/Al ratio, resulting in less ordered structures. The positions of the water molecules in the straight and sinusoidal channels for the ZSM-5 samples were mainly determined by the location of the charge compensating cation(s) in the structure, as was shown by the concentration profiles.

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In search and rescue (SAR) missions every minute counts. Semi-collapsed buildings are among the difficult scenarios encountered by search and rescue teams. An UAV-based exploration system can provide crucial information on the accessibility of different sectors, hazards, and injured people. The research project “UAV-Rescue” aims to provide UAV-borne sensing and investigate the use of AI to support this powerful tool. The sensor suite contains a radar sensor for detecting people based on breath and pulse movement. A neural network interprets the extracted data to identify signs of human life and as such persons that need rescuing. We also fuse radar and lidar data to explore the environment of the UAV and obtain a robust basis for simultaneous localization and mapping even under restricted visibility conditions. Additionally, we plan to use AI to support the path planning of the drone taking the digital map as input. Furthermore, AI is leveraged to map intact and damaged building structures. Potentially hazardous gases common to urban settings are tracked. We fuse the acquired information into a model of the explored area with marked locations of potential hazards and people to be rescued. The project also addresses ethical and societal issues raised by the use of UAVs close to people as well as AI supported decision making. The talk will present the system concept including interfaces and sensor fusion approaches. We will show first results of a research project from static and dynamic measurement campaigns demonstrating the capability of radar and lidar based sensing in a complex urban environment.