The apparatus, which may have a configuration similar to that of {HEAD ~ a felt tip} marking {TAIL ~ pen}, allows convenient use of low volatility solvents in the catalyst solution 
The apparatus , which may have a configuration similar to that of { HEAD ~ a felt tip } marking { TAIL ~ pen } , allows convenient use of low volatility solvents in the catalyst solution
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH