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EU V1.3 dual cells are loading! [UPDATE#5 - Could a loaded Celani wire become a high temperature super conductor?]

Written by Robert Greenyer on .

Mathieu reports that the V2 protocol is in the loading phase now n the EU.

Ryan is preparing a blog on the calibrations for both the EU and the US apparatus that have been running through their calibrations these past weeks.

The US cells are just a few days behind.

Go check out the LIVE DATA for

Cell EU1.3A

on the shiny new viewer.

Thanks go to Scott! 


UPDATE#1 - Loading success

Loading of the EU1.3A 400+L class Celani wire was a success and here is how it how it looked on the shiny new HUGnetLab data view...


UPDATE#2 - Wire changing mode?

It looks like the wire, whilst still loading, went through a bump and is potentially in an excess heat mode - you can see T-Mica and outer cell temperatures rising when ambient (listed on other cells data) is doing nothing in particular. We don't want the wire in potential excess heat mode now, we want to try and load it some more. So we are going to cool down the cell, vacuum out any water that has been created from hydrogen reduction of wire oxides and then run through a few load/cool cycles.

Check out the graph!


UPDATE#3 - Pretty wires

Mathieu just took an image of the wires as the cell cooled down because they look pretty. The blue is NiCr and the brown one is the Celani wire.


UPDATE#4 - Video of Setup

Here is Mathieu explaining the configuration of the cells.


UPDATE#5 - Could a loaded Celani wire become a high temperature super conductor?

So over the past few days, we have been cycling the Celani wire in an H2 atmosphere to load it by passively heating the cell via 35W into the NiCr wire. This pretty much causes the exact same swing between the powered on state and room temperature. As this is happening, the wire's resistance is dropping but the rate is reducing with every cycle. The same can be said for the resistance drop at room temperature, but the rate of increased loss in resistance, whilst reducing, is less than that of the high temperature rate reduction. Make any sense... though not. So here is a picture where you can intuitively see what I am talking about.



and here is a plot of the minimum resistance difference peak to trough on successive loading cycles:

The first comparative is greater due to vacuum application, H2 refresh and NiCr power increasing from 30-35W. Over the first six cycles shown in the screen capture, the peak to trough minimum resistance delta values in a power off cool down changed from 0.482 to 0.826 Ohms, a 71% change in nominal reduction in resistance from power on. More significant is the swing compared to the on resistance, which is also dropping, so the swing is over 85% higher in the sixth peak to trough.

Now everyone knows that resistance in these wires will go up and down based on temperature and we know that loading with hydrogen makes the resistance drop. What is interesting here is that it is also seemingly making the effect of the same change in temperature causing the resistance to drop faster.

Now what if a loaded wire was deliberately cooled below room temperature, with the apparent enhancement in resistance drop, could we get to a point where the wire became a high temperature (relative to absolute zero) superconductor?

Maybe we have an exciting test to add to the end of the protocol when the experiment ends?

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0 #36 Ecco 2013-06-24 10:22
It looks like that the mild vacuum currently applied to EU cell A is partialy deloading the active wire from hydrogen, seeing how wire resistance is increasing.

EDIT: maybe it was mainly the decrease in active wire measuring current which caused that.
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0 #35 Ron B 2013-06-24 02:04
Is it over for the EU cell on this part of the protocol? I hope not, I was sure looking forward to seeing the resistance bottom out and start to climb.
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0 #34 Ecco 2013-06-23 11:05
Actually I didn't mean to suggest a shorter power cycling (for example 1 hour/30 minutes instead of 6 hours/1hour) - although that might be an idea too - but instead to increase the rate of cooling when power is removed (for example by actively cooling the cell with a blower or something else) and/or the rate of heating while temperature is rising toward the 35W temperature level (by temporarily boosting heater wire power during the heating phase, or by applying a small current to the active wire).

In other words, making the cell cycle between a goal maximum temperature and a goal minimum temperature in the shortest time possible. Ideally, with no "holding" time.
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0 #33 Robert Greenyer 2013-06-23 10:23
Loading so far has given us a 24.23% drop in resistance from R0.

You may be right about the cycling. I think we can do a set of faster cycling. There may be a little time before the US team has caught up.
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0 #32 Ecco 2013-06-23 09:18
I doubt that the currently set power cycling is for all intents and purposes doing anything else other than allowing measuring wire resistance when power is off.

If you download the active wire resistance data and remove the periods where power gets switched off you get the expected curve for hydrogen absorption under constant conditions.


i.imgur.com/BADoT5p.png[


i.imgur.com/TXJjkk6.png

To be fair there are indications that on the first 2-3 cycles in the graph above this might have increased loading a tiny little bit, meaning that to make this cycling have a tangible effect you probably need to cool and/or reheat the wire faster, which you probably don't want to attempt doing at this stage.
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0 #31 Ecco 2013-06-22 23:00
Celani reportedly uses his wires for months under higher pressures than what the MFMP is using before they have to be replaced.
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0 #30 Edwin Pell 2013-06-22 18:53
Quoting Mathieu Valat:
it would also means we can keep on loading the wire even when the resistance is not showing decrease.


Mathieu, I agree, we could even see the resistance start increasing but hydrogen loading would still be increasing. Unfortunately we do not know if too much can become bad. If very high loading causes mechanical swelling and numerous large cracks it could be bad. Can Celani give any guidance on loading level?
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0 #29 Edwin Pell 2013-06-22 18:47
fitting the hot and the cold resistance versus loading cycle we get

Rhot = 15.1123*(cycle^-0.0610)
Rcold = 15.5852*(cycle^-0.0454)

cycle hot cold
10 14.04 13.13
100 12.64 11.41
200 12.25 10.94
300 12.03 10.67
3000 10.84 9.27
30000000 7.13 5.29

I expect other factors come in to play long before the 30 millionth cycle. Also long before the 100th cycle.
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0 #28 Mathieu Valat 2013-06-22 18:04
Thanks for you input Ed, your explanation makes sense to me.
It is a good sign, but it would also means we can keep on loading the wire even when the resistance is not showing decrease.

It would be interesting to make 2 hours symmetric cycles of heating cooling to show if that does as I say.
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0 #27 Edwin Pell 2013-06-22 17:57
Mathieu, the temperature dependence is something that has an activation temperature between room temp and 170 degrees. It is something that decreases the mobility of the electrons in the nickel/copper. It could be the hydrogen that is in the nickel/copper lattice. When cool it is not ionized, it is a neutral impurity that has little impact on the electron mobility. When hot 170 degrees it is ionized and as a charged impurity it causes electron scattering that lowers the net mobility. As more loading takes place the amplitude of the hot/cold difference increases. This is what we see in the data.

The initial step down in resistance with loading may be hydrogen in inter grain boundary spaces. The later loading may be into the lattice itself.

Ed Pell
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0 #26 Mathieu Valat 2013-06-22 17:56
I still have to investigate why the resistance increased during the calibrations, but I am pretty sure this is due to direct current under vacuum.
I image there were some water/moisture inside the wire from the preparation and the plastic bag.
What do you think?
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0 #25 Robert Greenyer 2013-06-22 17:50
@Ecco

Yes, under any measure now though, we have probably exceeded our loading success when compared to previous experiments. And this bodes well.
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0 #24 Ecco 2013-06-22 17:22
@Robert Greenyer: I previously mentioned that R0 was 18.45 Ohm, but that was under conditions comparable to current ones (250 mW at the active wire, pressurized hydrogen atmosphere, no heating, pre-loading conditions).

If we were to reduce pressure to 1 atm or applying vacuum, active wire resistance would likely decrease even further, but in turn also probably be in closer testing conditions to those of when the R0 value from the spreadsheet was obtained.

When and how should R and R0 be measured, when used to obtain the R/R0 ratio?
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0 #23 Robert Greenyer 2013-06-22 17:14
For those that might have missed it (and I did - doh!) the wire characteristics including R0 (initial resistance value at room temp is on the second tab sheet)

quantumheat.org/.../...

R0 was 17.31 Ohms

Given that the resistance drop after cool down is getting larger, taking the last drop from the current value, we are likely to have exceeded 23% by this calculation, making this already our best loading to date - and only passively!
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0 #22 Mathieu Valat 2013-06-22 14:34
Actually, no it is still periodically varying ±1.5°C
Sorry for that :D
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0 #21 Mathieu Valat 2013-06-22 14:28
Something very interesting is going on right now.
T_mica is rising where P_in is constant.
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0 #20 Mathieu Valat 2013-06-22 13:53
I am not so intrigued by the current/pressur e reading, it is highly correlated by the resistance/temp erature of the wire and the cell.

The PSU that supplies the Celani wire is not controlled in power. It is just behaving in a constant voltage mode, I should have put it in constant current mode. My bad.


However, increase of the resistance drop as it cycles is something of a great interest.
It might be related to hydrogen diffusion inside the constantan lattice.

I think about doing such thing with different diameter of wires and define what would be the physical limit.
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0 #19 Ron B 2013-06-22 13:26
@Ecco,
Those bumps look like what I'm seeing on the pressure. Very curious
.EU1.3A 30 Sec
06/21/2013 14:00:00 06/21/2013 20:00:00

Robert, excellent observation on the resistance going lower on each cycle.
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+1 #18 Robert Greenyer 2013-06-22 12:23
@Ecco

Not a bad suggestion on the extrapolation idea.

Interesting to note on monitor current.

We intend to play safe with this wire to start with and focus on primary goals. Later, regardless of the outcome, we can be more adventurous. Having said that - the wire is performing very well and we do want to try and have a record breaking loading of around 30%, so let's see.
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0 #17 Ecco 2013-06-22 10:24
@Robert Greenyer

I think that is naturally following the slow drop in resistance when power (heat) is applied.

It did decrease quite a bit, though, from 18.45 Ohm (on 2013-06-19 18:53 UTC) to 13.51 Ohm. That's a R/R0 value of 0.732 (measured with 250 mW on the active wire, no external heating. I'm not sure if these are the proper conditions for R/R0 measurements and calculations).
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