At 08:30 PM 9/11/2009, you wrote:
I guess it's better to wait until the coldfusionproject list's membership builds up (in quantity I mean, it's quite good already in terms of quality I see) before we shift the technical discussions there?
I intend to establish some structural stuff for the informal "association." I will probably also pose some questions that we can start to address. But anyone is welcome to start threads there, as long as it is about engineering kits or related. I prefer to stay away from theory, there, unless it is closely related to kit design. What is essential is that the project list remain focused.
A couple points: - the Galileo Project protocol seems a good basis, I say let's not bother with a closed cell and associated risks.
I'd still rather keep it on the table. I haven't given all the reasons for "semi-closed." I.e., routinely closed, but with pressure relief. For one thing, I don't want the experimenters to have to keep filling the cell with heavy water. On the other hand, I wouldn't rule out, either, kits using ordinary water, and I see no reason to seal light water cells unless we are using light water as a control or variable vs. heavy water, in which case the cells should be otherwise identical.
- what's the cathode's substrate wire material in the TGP, it's silver isn't it?
Yes. They used a platinum anode, which is the single most expensive component. Would silver work?
- what's the electrolyte volume in TGP, 25ml right? Why would you want to make a smaller cell?
Well, the parts list says that 100 g of D2O will do for 2 or 3 cells. The protocol talks about "adding" up to 25 mil per cell of D20, but that is in addition to the 10 mg per cell, so it's about 35 mil max.
If we use standard CR-39 chips, as shown (they are clear at the beginning, as seen in the photos. They are milky, after electrolysis. It's not the solution itself that changes them, a no-electrolysis control seems to remain clear. This is good news; we may be able to package complete cells and they might have good shelf life. A cell with no electrolysis is a nice control for possible radioisotope contamination from the cathode or other materials. (However, contamination of the palladium in the palladium choloride would not show up in quantity until the palladium is plated onto the cathode; possibly another test would be some of the palladium choloride spooned onto a chip to sit for a time.)
- shouldn't we go for one of the "impatient" protocols? (producing pits in days instead of weeks)
Perhaps, speed is desirable. However, reliability is more desirable. I certainly don't know anything like enough to decide yet, for myself.
Now that I'm reading the protocol in more detail, I appreciate the design and work that was done. The GP, provided as a kit ready to go, would be adequate. They say that experimenters should be prepared to spend about $700, excluding a power supply, giving enough material for two to three cells. Remember, this includes doing all one's own CR-39 etching, probably the most hazardous of the procedures. There would be value in a simple GP kit, and my guess is that it could be offered for less than that and still have room for profit.
Looking at the bill of materials provided with the protocol, I estimate $58 as a cell cost. The rest is setup and etching and the like. It also looks to me like the cells are about twice as big as necessary, unless the anode and cathode must be further apart than they would be if the cells were half the size. (i.e., the square becomes a 1:2 rectangle). This would use half as much deuterium. If we want the same total plating on the cathode, there is no savings on the palladium. The single biggest cost with the Galileo design is the platinum anode. In prototyping, both cell sizes could be tried, the difference would be the concentration of PdCl and LiCl in the solution; maybe it would be better to go for less palladium/lithium so that the initial concentrations are the same. These are small variations that might be significant, but which would easily be tested if the effects aren't known.
