From what I've seen on the web the 50/50 ammonia hyrogen peroxide mixture (APM) solution for chemical cleaning was originally developed by Werner Kern at RCA in the mid-1960s, for application to the cleaning of polished silicon wafers prior to semiconductor fabrication, where APM was known as RCA's "Standard Clean" step 1, or SC-1 which also became known as RCA-1 after it was more widely adopted across the industry. RCA-1 specifies 1-part each of industrial strength ammonia and peroxide (27% and 30%, respectively) diluted into 5 parts de-ionized water, effectively reducing the concentrations to 11% or 12% (i.e., comparable to the concentrations of household products). The
RCA-1 recipe is 5 parts of water, 1 part 27% ammonia and 1 part 30% hydrogen peroxide. I would avoid heating the mix as far as cleaning lenses goes.
The peroxide I got off Ebay is 12% and the ammonia 34% and I use 3 lots of peroxide to 1 of ammonia and then add 4 lots of water so is not the same as above but works for me.
I've seen warnings against using ammonia alone due to its high pH and the risk of etching glass but mixed with peroxide it should reduce the alkalinity. Warning: I'm not a chemist or a deep thinker so no guarantees.
I've also seen warnings against soaking cemented elements for any length of time and instead the advice is to wipe the surfaces (gently) using cotton buds.