The axion-photon mixing and the extragalactic magnetic background: plateau regimes, resonances, and non-Gaussian boosts

A NOTE ON GROUPS WITH MANY NORMAL-BY-FINITE SUBGROUPS

A subgroup $X$ of a group $G$ is called normal-by-finite if it is finite over its core $X_G$. We investigate the behaviour of uncountable groups $G$ of regular cardinality $\aleph$ in which all subgroups of cardinality $\aleph$ are normal-by-finite. Moreover, generalized soluble groups whose subgroups of infinite rank are either normal-by-finite or contranormal are characterized, and the analogous problem is considered for uncountable groups whose subgroups of large cardinality satisfy the sa...

Comparative assessment of magnetic pretreatment across low to moderate intensities for enhancing anaerobic digestion of sewage sludge

This study investigates the effect of static magnetic field (SMF) pretreatment at different field intensities on the anaerobic digestion (AD) of sewage sludge. Three SMF intensities (10, 20, and 50 mT) were applied through tubular magnetic polarizers under varying numbers of magnetization cycles (NMC) to assess their impact on biomethane production. The 20 mT condition with a single NMC yielded the highest improvement, increasing methane production by 21% compared to the untreated sludge. Low...

A proof-of-concept study on continuous side-stream low-intensity magnetization during anaerobic digestion of sewage sludge

Municipal wastewater treatment plants face increasing pressure to improve energy recovery while reducing sludge volumes and operational costs. In this context, low-input process intensification strategies are of growing interest. This study evaluated a continuous side-stream magnetization strategy applied during 44 days of mesophilic anaerobic digestion (37 ± 2 °C) of sewage sludge, where digesting sludge was continuously recirculated through a tubular rare-earth-material magnetic polarizer g...