SuperMALT: Physical and Chemical Properties of Massive and Dense Clumps
  The SuperMALT survey is observing 76 MALT90 clumps at different evolutionary
stages (from pre-stellar or quiescent to HII) in high excitation molecular
lines and key isotopomers using the Apex 12m telescope with an angular
resolution of $\sim$20" and a velocity resolution of $\sim$0.1 km/s. The aim of
this survey is to determine the physical, chemical, and kinematical properties
of the gas within clumps as they evolve. Here we report some preliminary
results based on observations of the $J$=3-2 \& 4-3 lines of HNC, HCN, HCO$^+$,
N$_2$H$^+$ and of the $J$=3-2 line of the isotopologue H$^{13}$CO$^+$. We find
that the morphologies and line profiles vary with the evolutionary stage of the
clumps. The average line width increases from quiescent to HII clumps while
line ratios show hint of chemical differences among the various evolutionary
stages.
