No abstract available

No abstract available

No abstract available

[en] The structure of a flat-plate photovoltaic-thermal system and its thermal circuit are considered. A method is proposed for the determination of heat losses and the temperatures of the front layers of a photovoltaic-thermal system with the specified operation conditions and a known temperature of the absorbing surface.

[en] The decay of V_nO_m⁺ and Nb_nO_m⁺ clusters sputtered under bombardment of the surfaces of vanadium and niobium with Xe⁺ ions and oxygen inflow is investigated by secondary-ion mass spectrometry. Based on experimental data, the excitation energy is calculated within the framework of the theory of unimolecular reactions. It is demonstrated that the numerical values of the specific excitation energy of V_nO_m⁺ and Nb_nO_m⁺ within the accuracy of the procedure do not depend significantly on the number of atoms that make up the clusters, nor on their type.