As most know, OA is a flash treatment that lasts about 3 days tops as the bees see the re-crystallized OA as trash and haul it out.
While at the last mtg in Ohio, Randy O. suggested to me to try vaporizing OA dissolved in glycerin to perhaps lengthen the killing time of OA in the hive. I'm thinking (and need some help here) that if you're vaporizing let's say 10 doubles, you'd mix 20 grams (2 grams for each hive) with XX (again need some help) amount of glycerin and vaporize by placing 2 grams of the OA mixed with glycerin into the inverted teflon cap. Then place the inverted cap on the inverted PV 110, insert into the hive and turn the PV upright and allow the vaporization to occur.
I don't know (as I've not tried this yet) how long the vaporization would take. I'm guessing not as long as vaporizing crystallized OA.
I will give this a trial, but just don't have time at the moment.
Anyone with a ProVap want to give it a try and report back?