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We investigate photon, pion, and $\rho$-meson production from proton synchrotron radiation in the presence of strong magnetic fields. The proton decay widths and the luminosities of the emitted particles are calculated within a relativistic quantum framework that incorporates Landau quantization. A scaling rule is derived for the transition probability between different Landau levels. This allows an evaluation of transitions for extremely high Landau numbers exceeding ${10}^{15}$. Furthermore, we calculate the momentum distribution of the emitted particles by properly including the proton recoil effect associated with particle emission. The results differ significantly from conventional semiclassical approaches. 

Six members of the 1,ω-bis(4-cyanobiphenyl-4′-yl) alkanes are reported and referred to as CBnCB in which n = 1, 15, 16, 17, 19 and 20 and indicates the number of methylene units in the spacer separating the two cyanobiphenyl units. The behaviour of CB3CB is revisited. The temperature dependence of the refractive indices, optical birefringence, and dielectric permittivities measured in the nematic, N, phase for selected homologues are reported. The dimers with n ≥ 15 showed an enantiotropic N phase, and for the odd members the twist-bend nematic, NTB, phase was observed. CB3CB shows a direct NTB-isotropic, I, transition whereas for CB1CB a virtual NTB-I transition is found. The temperature dependence of the bend elastic constant, K33, measured in the oblique helicoidal cholesteric state formed by mixtures of CBnCB with a chiral additive S811, shows strong non-monotonous behaviour with a deep minimum near the transition point to the NTB phase. The minimum value of K_33 decreases as n increases. The long even members of the CBnCB series show similar values of TNI to their odd-membered counterparts but their estimated values of TNTBN are considerably lower. This is attributed to molecular shape and its effect on K33. 

Atomically precise nanoclusters (NCs) provide useful model systems for studying fundamental aspects of the metal-catalysed CO₂reduction reaction (CO₂RR).