Resonance-like nuclear processes in solids: 3rd and 4th order processes

It is recognized that in the family of heavy charged particle and electron assisted double nuclear processes resonance-like behavior can appear. The transition rates of the heavy particle assisted 3rd-order and electron assisted 4th-order resonance like double nuclear processes are determined. The power of low energy nuclear reactions in $Ni-H$ systems formed in $Ni$ placed in $H_{2}$ gas environment is treated. Nuclear power produced by quasi-resonant electron assisted double nuclear processes in these $Ni-H$ systems is calculated. The power obtained tallies with experiments and its magnitude is considerable for practical applications.