  The behavior of small samples in very short and intense hard x-ray pulses is
studied by molecular dynamics type calculations. The main emphasis is put on
the effect of various tamper layers about the sample. This is discussed from
the point of view of structural imaging of single particles, including not only
the distortion of the structure but also the background conditions. A detailed
picture is given about the Coulomb explosion, with explanation of the tampering
mechanism. It is shown that a thin water layer is efficient in slowing down the
distortion of the atomic structure, but it gives a significant contribution to
the background.
