  In this paper will be applied some principles and methods from econophysics
in the case of the direct foreign investitions (D.F.I.), particularised for the
Greenfield type, and mixed firms of trade and industrial production (Joint
Ventures). To this aim will be used some similarities and parallelisms between
the mentioned economic domains and some phenomena and processes from physics,
especially from thermodynamics, solid state physics (the grow of crystals and
thin policrystalline layers etc.), electromagnetism etc.
