  A solution of the modified Boltzmann transport equations is found, which
describes features of the spin and charge transport in a solid. Two
modifications of the Boltzmann transport equation were introduced. The first
modification describes the fact that a delocalized electrons can either be of
the running-wave type or the standing-wave type and electrons of different
types contribute differently to the transport. The second modification includes
the fact that the direction of the electron spin may not be conserved after
frequent electron scatterings. The origins and features of the spin proximity,
spin injection and spin detection effects are described. An enhancement of spin
detection and spin injection efficiencies in the vicinity of an interface are
predicted. The physical mechanism of an enlargement of spin accumulation due to
the conventional Hall effect is described.
