First of all, I would like to thank Randy for his scientific rigor and his devotion to promoting knowledge and understanding.  I am even more fascinated by MAQS now than I was before as the saccharide matrix is more sophisticated than I had originally thought.  I would just like to clarify that my original and subsequent posts on MAQS was only to reinforce the idea that formic acid is the active agent in the strips and that one shouldn't consider them anything more or less than that.  
The secondary and perhaps more pertinent question, Do MAQS provide a delivery system that provides a significantly more reliable formic treatment in terms of vapor concentration and duration within the hive?  Anything at this point is just my thought process and not to be taken as fact.  Also I tend to be overly pedantic, apologies ahead of time on that.

The variables are far too complex and it is substantially more of an engineering problem than chemistry, however diffusion of any volatile substance is going to have a strong dependance on temperature, surface area, and the direct environment to which the source of the volatile substance is diffusing.  With MAQS there is an additional variable, that of water diffusing into, and out of the saccharide polymer which at some level is going to control the available pool of formic acid from the reservior of formate esters on the saccharide (since I have no idea the structure we must assume it is a black box that releases formic acid at some rate that has a dependency on ambient water, which may or may not be constant over a large range of humidities).   So if we simply consider the formic acid that is release from the saccharide and travels to the outside membrane (looks a lot like thick paper to me) then to a first approximation, the total concentration of formic acid in the hive as vapor is determined by the rate at which it diffuses off the membrane, minus the rate at which it leaves the hive through whatever openings are available.  
  All of the various formic acid treatments that I have read about on the webs use some method to achieve a window of formic acid levels that the experimenters want.  Clearly, people figured out that absorbant pads soaked with formic acid solution allowed for too rapid evaporation, so then meat pads which are perforated plastic envelopes with the absorbant pad inside were used.  Various sized trays with varied formic acid solutions have been used.  In these cases the relevant parameters are temperature, surface area of the tray, and amount of evaporation blocking agent used, aka water.  The more water you add to neat formic acid the more you physically block it from getting released into the atmosphere.  This might sound like a strange way of thinking about it but you can consider the evaporation of the water and formic acid in any solution to be completely independent.  This is directly analogous to using salt in the ice of your ice cream maker.  Ice melts in water in an equilibrium process, water molecules come off the ice at a certain rate and they go back on at a certain rate, dependent on temperature.  In pure water, an equilibrium temperature of zero decrees celsius (32 F) is reached where each water molecule released takes energy from the system, as the temperature goes below zero, the rate at which water molecules for back onto the ice increases, water molecules going back onto the ice release energy push the temperature up and keep the system at zero degrees.  If you add salt, it simply provides a physical impediment to water molecules getting back onto the ice, so it slows down the "on rate" but has no impact on the water leaving the ice, so the balance of on rate and off rate favors the off rate and that requires energy so the temperature drops below zero.  
  In the case of formic acid solutions, the water acts like salt, preventing some portion of the formic acid molecules from reaching the surface of the solution, thereby slowing the rate of evaporation into the air.  
   This is why the percentage of formic acid in any given solution is largely irrelevant to a treatment.  A 10x10 tray of 50% formic acid can provide a much higher concentration of formic acid vapor than a 1x1 tray of neat formic acid in the same volume, but it all depends on the size of the box your fumes are going into and the rate at which formic vapor escapes.
Anyway, that was longwinded... 


My gut feeling is MAQS are as close as close as I have seen to provide such a formic treatment system when one considers the balance of all aspects of mite treatment with formic acid.  No special equipment is required, and treatment is fast about the same time it takes to put on a pollen patty.  They also minimize the chance for dosing errors and are readily available.

Mark
   

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