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We describe the electrochemical α-amidoalkylation of γ-lactams based on transition-metal-free cross-coupling via hydrogen atom transfer. The highly selective hydrogen atom transfer process allows for a broad substrate scope including both inter- and intramolecular reactions. Also, the construction of quaternary centers was realized by a double hydrogen atom transfer protocol to afford spirocycles. Detailed mechanistic studies including experimental and computational studies are provided to support the reaction pathway.

High-current impulse experiments were performed on volcanic ash samples to determine the magnetic effects that may result from the occurrence of volcanic lightning during explosive eruptions. Pseudo-ash was manufactured through milling and sieving of eruptive deposits with different bulk compositions and mineral contents. By comparing pre- and post-experimental samples, it was found that the saturation (i.e., maximum possible) magnetization increased, and coercivity (i.e., ability to withstand demagnetization) decreased. The increase in saturation magnetization was greater for compositionally evolved samples compared to more primitive samples subjected to equivalent currents. Changes in remanent (i.e., residual) magnetization do not correlate with composition, and show wide variability. Variations in magnetic properties were generally more significant when samples were subjected to higher peak currents as higher currents affect a greater proportion of the subjected sample. The electrons introduced by the current impulse cause reduction and devolatilization of the ash grains, changing their structural, mineralogical, and magnetic properties.

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The designed and fabricated patch antenna covers both dedicated short‐range communication (DSRC) and Fifth Generation (5G) millimeter‐wave (mmW) bands for advanced telematics. The fabricated antenna has a small volume of 2.7λH × 2.6λH × 0.15λH, where λH is the air wavelength of the highest operating frequency. The antenna performances, such as S‐parameters, the realized gain at boresight (RG00), antenna radiation efficiency, and radiation patterns, are reported. The simulated results are in good agreement with the measured ones. Despite the fabricated antenna's compactness, port isolation higher than 31 dB was achieved. Not only high RG00s of 6.8 and 12 dBi were obtained at DSRC and 5G mmW bands, respectively, but also an efficiency greater than 90% was observed at both frequency bands. Lastly, the fabricated antenna shows better performance than the previously reported dual‐band antennas.