Posts by jeff

Calculating energy to a load can easily be accomplished for arbitrary voltage and current waveforms even if voltage and current are out of phase, as will be the case for reactive loads. The easiest method is to use a shunt resistor to generate a voltage proportional to current and use a voltage divider to reduce the AC mains voltage to a level compatible with IC technology. Using a DAQ module, the two captured voltages are then multiplied, and the absolute value is taken to insure a positive result. This process must be done at a sampling rate sufficiently high to capture the high frequency harmonics that are a consequence of phase controlled power. Each ABS( V*I) sample is equivalent to the energy/sample rate, so the total energy is just the summation of the ABS(I*V) samples. Non-contact current probes are OK if they do not introduce delays and have a sufficiently high bandwidth. It is important that both I and V for each sample represent the same interval in time. The procedure outlined above works for single phase. 3-phase can be measured in a similar way, but the three sense circuits must be galvanically isolated.

The principle of least action, when formulated in quantum field theory, leads naturally to Feynman's path integral approach, which can then be applied to either QED or QCD. As stated above, however, the maths get complex in a hurry.

Some ECAT replication efforts yield COPs >1 but most do not. For example: Parkhomov is having difficulty replicating his results because he is using a different Ni powder. I have run several ECAT-like experiments, all yielding null results, and suspect other replicators have had similar experiences. All these experiments use similar active ingredients: Ni, LiAlH4, H2 gas, and yet there is a troubling lack of repeatability. So some key parameter is missing. I suspect the lack of reproducability can be traced to pre-treatment of the Ni and a lack of understanding regarding exactly what the pre-treatment process is doing. Zhang-Hang states the Ni in his experiment was pre-treated. Is any way to find out details of his pre-treatment protocol?

To make real progress in LENR and convert it to a physics and engineering discipline it will be necessary to develop a workable theory that bridges the gap between QM interactions among a few particles and scale those QM methods to comprehend structures consisting of hundreds to thousands of atoms. Software tools of this type exist, although they may not have the proper QM approximations for non-stationary potentials or a treatment of the uncertainty relationship that takes into account correlation between operators.

I recently purchased a sample of passivated Li nanopowder from Looking for Heat. Prompt service.

Thanks for the data. I will, however, need to look up the gamma energies to make a positive identification. If they are in the 10-200 KeV range then the CdTe detector will be able to capture them. There are quite a few gamma energies listed for the Rn decay chain, so it may take a while to identify them.

Alan and Mark have been kind enough to lend me a cooled CdTe gamma spectrometer for a few days. With it I was able to calibrate from a known source and then measure the spectrum of dust captured by running the basement furnace fan. Some qualitative conclusions. Most of the radiation I could measure consists of betas. A few seconds from a 1 uC Co57 source was sufficient to generate ~100 samples in some channels. By contrast, it took over 10 minutes to get sufficient events to construct a usable spectrum from the dust. So the gamma emanation levels from dust are relatively low.

But the dust still registers >5 mrem/hr with a GM detector, so the CdTe detector must not be capturing most of the events. To differentiate between radiation types I placed three different absorbers between the air filter and a GM pancake detector: 0.15 mm Al, 0.9 mm Pb and 17.5 mm Pb. The Al had almost no effect on radiation levels, so it's not alphas. 0.25 mm Pb stopped almost all radiation, so it could be betas or low energy gammas, but the CdTe detector did not detect high gamma rates in the 10-100 KeV range. A 661 KeV Cs137 source produced gammas that easily went through the 0.15 mm Pb, but no through 17.5 mm of Pb. So by the process of elimination it would appear that most of the radiation from the dust is betas.

Using a sufficiently long acquisition time it was still possible to get a repeatable 10-130 KeV gamma spectrum from the dust. I'm still evaluating the data to determine the isotopic species that would produce the observed spectrum. BTW, the CdTe detector has excellent resolution, coming close to a LN2 cooled Si or Ge detector. The only limitation is imposed by the detector's small size which precludes accurate measurement much above 100 KeV due to the fact that the high energy gammas exit the detector before losing their full energy. I'll publish the isotopic results once I match gamma energies to isotopes.

Avoiding LiAlH4?

Does any one have an opinion regarding replacing LiAlH4 with passivated Li powder, Al powder, and supplying the H2 from an external source? This is really a question as to whether LiAlH4 produces morphological changes to or with the Ni powder that would not be obtained by using elemental species.

The obvious reason for considering this approach is the hazardous nature of LiAlH4.

I made measurements without running any equipment that uses fans and found that rad levels did not rise above the 0.03 mr/hr which had been established as a background level. So as long as none of the equipment concentrates dust, it should be possible to perform rad measurements down to background. As a final experiment I removed the cell from the calorimeter chamber and heated the Ni wire with the cell set on the table on a ceramic tile. No radiation above background was observed at the voltage levels previously tested. I think this makes a fairly strong case for the hypothesis of accumulated radioactive dust. But best most persuasive proof would be to obtain gamma spectra from the dust.

I chose to look for radiation because, if detected, it provides much more information about the underlying processes than does a positive COP. It is only about a half hour procedure to reconfigure the apparatus to operate in the calorimeter mode.

I have run both Rossi and Celani types of experiments, and have so far seen only null results. It is fairly easy to change out the innards of the cell to accommodate either Joule heated wire or Kanthal over alumina to heat a stainless steel capsule containing Ni, Al, Li. In both cases H2 and vacuum are controlled by the same set of valves and tubing. The quartz tube and associated feed-throughs remain the same. This is the first time I have made a concerted attempt to observe radiation. In the past the GM detector was placed near the cell and served a safety monitoring function only.

The answer is "yes", and it was in doing just such a test that I noticed a slowly increasing radiation level with no heating. This aroused suspicions that a process other than LENR was responsible.

I'm hoping to get hold of a gamma spectrometer. I'll collect a dust sample, confirm the level of radioactivity with a GM detector and then get a gamma spectrum. Many of the Ra -> Pb decay path isotopes emit gammas. So it should not be too difficult to look for matches on some of the stronger gamma energies.

Dust contamination

Many comments have mentioned dust contamination as something that might yield false positives, so I ran a quick experiment which consisted of turning on the blower fan in the heating unit in the basement. No heat, just the fan pulling air through the filter. After approximately 1 hour I opened the blower cabinet and measured an enormous level of radiation, almost 10 mrem/hr at the filter. Now things get even stranger. About six hours later the radiation level at the air filter had returned to background level of 0.03 - 0.05 mrem/hr. To make sure that this reading was not a fluke I wiped the TV screen (another place where dust collects) with a paper towel and measured a similar rad level on the towel. Just as before, after ~ 6 hours the level had returned to normal.

Here is what I believe is happening but I will not be able to prove it until gamma spectrometer measurements become available. Radon and its decay products may be entering the basement and sticking to dust particles. Most of the time the dust is fairly dilute, but under certain conditions (fans, filters) the dust can become concentrated. That would account for the monotonically increasing radiation levels observed in the airflow calorimeter. Dust was being pulled into the chamber at a faster rate than the Rn decay products were decaying. Once the fan was turned off no new Rn entered the chamber (or furnace air filter) and the radiation level returned to normal. The tricky part is that the half lives of Rn decay products have half lives measured in minutes, so 6 hours is many half lives. That would explain the apparent "activation" that I reported earlier. It was most likely radioactive dust with short lived isotopes of Po, Bi, Pb that I was observing. Look up the Rn decay diagram; half lives and decay products are listed. It would also explain why testing of dust on the floor and in a vacuum cleaner not used for weeks would return background levels.

Bottom line: I may not have observed LENR and almost certainly did not observe neutron activation. However, other Celani-type experiments have reported radiation and excess heat, so the experimental approach is still worth pursuing.

Note on the high radiation level measured on the air filter. The GM detector was enclosed in a polyethylene bag to prevent dust contamination, so some alphas would be stopped. Inserting 3 mil thick Al foil reduced the level by ~50% indicating that some of the radiation was alphas and betas. Inserting a 1.75 cm lead shield in front of the detector stopped almost all radiation. So it is likely that alphas, betas, and gammas were all present.

In order to guarantee that ambient radioactive dust is not causing false positives, I removed the cell from the calorimeter chamber and wiped down the chamber walls to remove as much dust as possible. Once again, the dust in the paper towel showed levels as high as 0.2 mrem/hr. The first step will be to monitor rad levels in the chamber with the fan turned off to establish a baseline, which should be close to the previously measured background of 0.03 mrem/hr. The next step will be to power on the fan while continuing to monitor rad levels. If the level remains the same then ambient dust is not a factor. As a supplementary test I wiped the floor with a damp paper towel and measured rad levels; they were at background levels. So I'm skeptical that ambient dust is a factor, but I'll run the experiment to confirm.

Activation of Elements in GM Detector

After running an experiment with Joule heated Ni wire in a low pressure H2 atmosphere I recorded a radiation level as high as 0.8 mrem/hr which is over 20x the 0.03 mrem/hr background level. This level is well in excess of anything I had recorded previously. To be sure the GC was operating correctly the detector was moved 20 feet away from the vicinity of the apparatus. Interestingly, it still registered almost the same reading. So my first suspicion was that dust was somehow activated or dust with a low level of radioactivity had accumulated on the detector. Blowing off the surface of the detector had no effect. Also, no other locations outside the chamber that could have collected dust had measured above background.

I then disassembled the detector and wiped all surfaces with alcohol. Not a good idea. The opaque coating on the detector window dissolved and was wiped away. However, its removal restored the radiation measurements close to background. The detector still works fine, and I can only speculate that the coating is intended to exclude light or perhaps to dissipate static charge. I mention this only because this phenomenon has been reported previously. See p 92 of Storms' "The Explanation of Low Energy Nuclear Reaction". Note: after cleaning and reassembling the GC I also wiped down the interior of the chamber with a damp cloth, and the dust on the cloth showed radioactivity over 5x background. So not only was the GM detector activated, but the dust in the chamber was also activated.

Given that the rest energy of a muon is ~207x that of an electron, yielding a value of ~105 MeV, I would be interested in understanding how muons could be created by any nuclear process involving lighter elements.

Jeff

Almost correct. In step 3 the pressure is 5 Torr, not 5 mTorr.

Jeff

Heating power to the Ni is furnished by an HP 6024A DC power supply. Voltage and current were measured to 4 digits with a Keithley 2000 multimeter.

Jeff

Brian,

I'm using commercial 28 gauge commercial quality Ni 200 wire. Radiation is being measured with a Ludlum model 3 survey meter and a 44-9 detector head. (Ludlum has a website that furnishes energy vs. sensitivity curves for their detectors).

Jeff

It may have, but until I attempt to repeat the experiment at higher pressures, it remains uncertain. It only by a a fluke (power supply could not heat the wire sufficiently with 1 atm of H2) that I even considered using reduced pressure.

Jeff