We plan to study dust properties in 30 clouds
  in the galactic center not associated with
  Sgr A and Sgr B2.
  Our ISO proposal follows up our spectral line investigations
  in more than 10 transitions of NH3, CO
  isotopes and CS at the central positions of clouds
  obtained from a CS survey.
  Kinetic temperatures from our data show
  that a great deal of the gas has a kinetic temperature of> 100K,
  while the temperature
  of dust in the galactic center seems to be about
  25K, but is not well determined for positions away
  from SgrA and B2, which may be exceptional.
  We plan to combine IRAS flux densities for shorter wavelengths
  with 200mu data obtained with ISOPHOT to determine the
  column densities and temperatures of the dust in our sample of
  well-studied clouds. The combination of the results on dust
  with our gas results will
  allow us to determine cloud luminosities, dust/gas ratios as
  well as cloud stability amd heating.
  These results will be used to interpret heating and cooling
  processes in our galactic center and
  to interpret molecular line and dust properties of other
  galaxies, for which we have insufficient angular resolutions.
  The most promising heating mechanisms are
  either cloud-cloud collisions, or a form of ambipolar diffusion,
  but NOT heating via cosmic rays.
  These studies will have great consequences for our understanding
  of interstellar clouds in the nuclei of other
  galaxies.