Structure constants of mesons in model of quark diagrams

The results are presented of calculating lower loop quark diagrams for the structural parameters describing the behaviour of electromagnetic and weak formfactors of pions and kaons in the region of small momenta transferred. The calculations are carried out on the assumption that there exists a global duality between quark loop diagrams and the contribution of the hadron resonance sum into the sum rule for the meson structural parameters resulting from the current algebra. Electromagnetic radii of pions and kaons are calculated. The K sub(l3)-decay parameters are discussed. The spectral sum rules for lepton decays of vector mesons and for structural parameters of the π → lνγ decay are considered