  Within a 2D model of Josephson junction arrays (created by 2D network of twin
boundary dislocations with strain fields acting as insulating barrier between
hole-rich domains in underdoped crystals), a few novel effects expected to
occur in intrinsically granular material are predicted including: (i) Josephson
chemomagnetism (chemically induced magnetic moment in zero applied magnetic
field) and its influence on a low-field magnetization (chemically induced
paramagnetic Meissner effect), and (ii) magnetoconcentration effect (creation
of oxygen vacancies in applied magnetic field) and its influence on a
high-field magnetization (chemically induced analog of "fishtail" anomaly). The
conditions under which these effects can be experimentally measured in
non-stoichiometric high-T_c superconductors are discussed.
