Posts by Arun Luthra

Quote from magicsound

Prototype half-scale cell 40 x 300 mm. The heater is a 150 watt cartridge inserted in the thermowell. I'll initially assemble it without Ni mesh, for vacuum testing and bake out. The ports are both 3/8" Swagelok, welded to the end caps.

Are any of these welding kits on Amazon suitable for these vacuum tight welds?

https://www.amazon.com/Forney-…64949001&s=gateway&sr=8-3 (flux core, gasless)

(potentially messy:

This one is only $100, requires your own oxygen and acetyline gas bottles I believe:

https://www.amazon.com/ZENSTYL…64949495&s=gateway&sr=8-4

Zeny Arc welder $118:

https://www.amazon.com/ZENY-We…64949802&s=gateway&sr=8-3

I have a 6" conflat blank on the way, I'm thinking about drilling two holes into and welding gas and heater to it.

Some blackbody radiation curves with 50 micron in the center.

Quote from Cydonia

Soon be patient, my friend Jacques and me stiil have to spend holiday time before

That is your chamber? I take it you will be operating at lower temperatures to be compatible with the glass components/fittings.

I am really tempted to get a glass conflat window. There is one rated to up to 200C. Perhaps I could use it on lower power runs.

Unrelated question: If the meshes are a source of energy, won't there be a ton of self-generated infrared light? Even if the original source of the reaction is not emitting like a blackbody, the meshes should self heat and that component will emit like a blackbody?

Edit: There are sapphire windows that go up to 450 C.

From Letts and Cravens laser beat frequency work, they saw high COP at 8.3 THz, 15.3 THz, and 20.4 THz.

Excerpting from a Letts/Cravens/Hagelstein paper: "Low-level thermal signals are observed to be triggered at apparent resonances when the difference frequency is 8.3, 15.3 and 20.4 THz. There seems to be a reasonable connection between beat frequencies of 8.3 and 15.3 THz and characteristic frequencies of the optical phonon spectrum in PdD, but the optical phonon spectrum in PdD does not go up to 20.4 THz. However, 20.4 THz is close to a characteristic frequency of PdH, and we believe that our experiments so far have had significant proton contamination."

The 8.3 THz and 15.3Hz pure deuterium frequencies correspond to vacuum wavelengths of 36 microns and 19.6 microns respectively.

The mesh has 55 micron diameter. I can imagine a surface plasmon resonance effect if the driving photons were coherent, but for a blackbody radiation it is not coherent. Maybe quantum effects allow random heat photons to result in resonance because out-of-phase incoming photons won't be able to disturb (couple to) plasmon oscillations that are already underway? I have no idea...

Smaller mesh sizes could be worth trying, after doing the 55 micron mesh. I emailed one vendor and got no response.

If smaller resonant cavities in the roughened surface matter, those are of course smaller than 55 micron.

NASA/Joe Zawodny did this type of O(10 THz) surface plasmon resonance work on micro-patterened surfaces but they went dark, not sure if it failed or not. They may have made too many experimental choices specific to Widom-Larsen theory, maybe that caused it to fail, or it just didn't work.

There are papers about 3D printing of micron scale THz radiation generators these days...

All of this will be tested quickly if Mizuno's work goes viral following ICCF.

Simpler vacuum setup than what I posted before. Added a Pirani gauge (The Edwards APG-L goes down to 0.01 Pa). Is it valid? The roughing pump just pulls through the Turbomolecular when the Turbo is off.

You can get the Edwards gauge for about $70 on Ebay. There is a controller for a few hundred dollars, but you don't need it. The device manual tells you how to attach a DC power supply and a volt meter, to provide power and measure the pressure.

You need an RJ-45 cable for the gauge (easy to find) and optionally this very nice and cheap thing to connect to the 8 pins:

RJ45 Ethernet Breakout Board Screw Terminal with Indicator LED

https://ebay.to/2KizmzJ

The instruction manual tells you what to connect to the different wires.

https://shop.edwardsvacuum.com/products/d02173000/view.aspx

Edit: P.s. This does not even include the deuterium plumbing yet!!

I'm probably going with this 300W power supply.

https://www.amazon.com/4-Digit…64622579&s=gateway&sr=8-7

edit: maybe not. More heater resistance research needed. I've seen some in the 100V/200V range.

Any thoughts on how to install those cylindrical barrel heaters to the endcap? I guess it's either a high vacuum weld (which I've read is a little more complicated than normal welding) or some kind of threaded connection.

Quote from Curbina

Hello Arun, if you can’t do an exact replication, you then call your experiment an “analogue” and document it as well as Mizuno/Rothwell did, with emphasis in the differences. We don’t know what is te key factor in Mizuno’s succes, we suspect it was the position of the heater, but also the low pressure might play a role. Try to be as exact in duplicating the reported conditions as you can, and if it does not work, and you document the differences of your analogue, then we all learn something valuable.

Agreed, certainly.

Was Mizuno using AC or DC?

Can anyone recommend a cheap power supply that runs on 110V and goes up to 500W?

The Turbolab is too expensive for me. In fact, I might just try to get a used Alcatel that goes down to 0.1 Pa or 0.01 Pa, without a turbomolecular pump. Simpler also.

Here is a vacuum system diagram involving a chamber, roughing pump, and turbomolecular pump:

Problem:

Mizuno apparently has just one vacuum system line coming out the endcap, next to the heater feedthrough. This is different from the standard situation where the turbomolecular pump is attached directly to the chamber.

The diagram below is a possible solution. Is it correct?

I understand conflats with copper gaskets. This is an impressive metal to metal seal suitable for ultra high vacuum.

1) It makes me wonder how a simple threaded hole in the side of a chamber works. Is it leak tight to 0.01 Pa?

2) Are the swagelok values that Mizuno used, infinitely reusable? Or are they single use like the conflat copper gaskets?

3) Are gas feed throughs like this one meant to be welded on?

https://sep.yimg.com/ca/I/vacuumshopper_2268_109766850

Are there any diagrams of Mizuno's vacuum system? I see that there is just one port leading to the roughing pump and the turbo molecular pump (TMP). I've read that TMP are supposed to have a very wide connection to the vacuum chamber, but I guess he found that this is good enough.

I'm curious what the plumbing looks like for stepping down the wide mouth of the TMP to the small tube, and what plumbing is used to connect both pumps to the same tube.

Not sure if this has been posted yet, but here is a good page on generating D2 has from D2O:

http://www.fusor.eu/deuterium.html

It looks pretty complicated, requiring lots of plumming, a PEM cell, a compressor, etc.

Is there a simpler solution besides buying D2 gas which is difficult to obtain?