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197) Second Oriani experiment in my lab
Ludwik Kowalski (December 23, 2004)
Department of Mathematical Sciences
Montclair State University, Upper Montclair, NJ, 07043
One can consider this to be a continuation of my unit #192. That was open electronic logbook that turned into a diary. I am going to be much more concise in this description. I am using the same cell but the CR-39 is from Fukuvi. At the end of unit #192 I explained why my previous experiment should not be considered as a replication of what was described in the unit #188.
Description of electrolysis:
a) 23 hours at the nominal current of 100 mA (pulsation due to bubbling)
b) 24 hours at the nominal current of 200 mA (pulsation due to bubbling)
c) Current was cut off for 10 minutes to bring the anode closer to the cathode and to reduce the anode diameter. This was necessary to eliminate pulsation).
d) 33.5 hours without pulsing. The current was growing slowly from 200 mA to 375 mA, as water was decomposed and the concentration of the electrolyte ~doubled).
Then water was added to return to the original concentration.
e) 14.5 hours without pulsing. The current was growing slowly from 375 mA to 510 mA, as water was decomposed and the concentration of the electrolyte ~doubled).
Then water was added to return to the original concentration.
f) 18.5 hours without pulsing. The current was growing from 350 mA to 600 mA, as water was decomposed and the concentration of the electrolyte ~doubled. Then water was added to return to the original concentration.
g) 16 hours without pulsing. The current was growing from 350 mA to 600 mA, as water was decomposed and the concentration of the electrolyte ~doubled. Some water was added after 12 hours to prolong the high concentration run. Then water was added to return to the original concentration.
h) 18 hours without pulsing. The current was growing from 350 mA to 600 mA, as water was decomposed and the concentration of the electrolyte ~doubled. Then water was added to return to the original concentration. At this point I accumulated 102.5 hours of normal electrolysis (after 47 hours of the electrolysis with the pulsating current).
A potential problem: I must address the issue of concentrations of the electrolyte. Both Oriani and me start from the same concentration (2.36 grams of Li2SO4 salt per 100 cm3). But my tube (total length above the cathode) is 7 cm while his is about two times longer. I must add the liquid when the level is 3.5 cm above the cathode (to have nearly 1 cm cover above the cathode. In going to that level the volume of my liquid is reduced by a factor of 3. It means my concentration increases by the same factor when water is decomposed. In longer tube the concentration changes by the factor of 4 or 5. This implies that some concentrations used by Oriani were never tried in my cell. In trying to replicate his findings I must run electrolysis at higher concentrations. To triple my minimum concentration, for example, I must add 2*0.29 = 0.58 grams of the salt before filling the tube to the rim.
But I have no scale at home. However my bottle with originally prepared electrolyte is not empty. Instead of adding pure water (as I do when the minimum level is reached) I will add the original electrolyte. This will add 0.19 grams of the Li2SO4, salt. (minimum concentration will increase by the factor of 1.65, doing it twice will increase it by the factor of 2.3 and doing this three times will increase it by the factor of 3.0. And one more dose of 019 grams of Li2SO4, would make the factor equal to 3.6. That is what I am going to do from now on -- refilling with the electrolyte instead of water. This will not take away racks that have already been accumulated so far in 150 hours. Who knows, perhaps the secret of success is in using high concentrations?
Yes, I know that ideally everything should be as constant as possible in a single experiment. Then one could change one parameter, for example, the current or concentration, and repeat the experiment. And that is what i might start doing when the goal will be to understand and to optimize. But for the time being the goal is to convince myself, and others, that the discoveries made by Oriani are real and worth focusing on. His philosophy is to scan over different currents and concentrations in order to approach 100% reproducibility. I am following this philosophy.
i) Add one dose of 0.19 grams of salt and run the cell for 4 hours at the nearly constant current (0.55A to 0.65A) to bring the level of the liquid to its minimum before the end of the day. After these 4 hours one of the two CR-39 pieces was removed from the inside of the cell. It was the chip K (Scratched cross was at the bottom; it was not facing the second immersed piece).
Also one pair of CR-39 touching the tube from the outside was removed. The piece facing the tube was G (cross and G are at the top, the side facing the cell was the one that had G and the cross). The other removed piece was L. It was behind the piece G. The cross and the L were near the top, as on the piece G. The side with L on it was in contact with the piece G. A fresh single CR-39 was placed to replace the G+L pair.
j) Add the second dose of 0.19 grams of salt and run the cell for 12 hours. During that time the current was changing from 020A to 0.25A in 5 hours and then kept more or less constant near 0.6A for another 7 hours.
k) Add the third dose of 0.19 grams of salt and run the cell for 12 hours. During that time the current was around 0.25A for the first 5 hrs and around 0.6A in the remaining 7 hours.
l) Add the fourth (and last) dose of 0.19 grams of salt and run the cell for 15 hours. (starting on 12/27/04 at 13:00). During that time the current was around 0.30A for the first 5 hours and around 0.6A in the remaining 10 hours.
m) Add pure water and run the cell for 12 hours. During that last electrolysis step the initial current was 0.35A and the final current was 0.6A.
The electrolysis will be stopped after that. Then fresh CR-39 chips will be applied to each side (was dry and was wet) of the Ni cathode. Perhaps absence of tracks during the electrolysis (I hope they will not be absent) does not mean that no tracks can appear later.
Description of detectors in and around the cell:
The exposed CR-39 area is about the same as in the experiment 192. But the area surrounding the tube is about 50 times larger than my single chip in experiment 192. That single chip caught a lot of tracks (more than ten times above the background) during the electrolysis but nothing after the electrolysis (as described at the end of the unit #192). I am focusing on tracks that Oriani discovered outside the tube. The tube is surrounded by large pieces of CR-39, as illustrated in Figure 1. The piece facing us is 5 cm long and 1 cm wide. Actually it is a set of two pieces, one behind the other. The cover, also a set of two pieces, is exposed to the escaping gases during the entire electrolysis. The set of two pieces might be able to detect neutrons, if enough of them are emitted to create recoiling protons. Note the holes drilled in CR-39. They will be used to suspend the pieces from thin nickel wire hooks during the etching (in hot NaOH).
I will describe and label these pieces in the next section. Two large CR-39 pieces, not visible in the illustration, were inserted into the electrolyte, above the anode. The level of the electrolyte changed due to decomposition of water. Therefore, only lower parts of the inserted CR-39 pieces are always in the electrolyte. The upper part of the inserted pieces are always exposed to escaping hydrogen and oxygen vapors. Middle sections are sometimes in the electrolyte and sometimes in the vapors. There is also a piece sitting near the top of the tube (without blocking the escaping H2 and O2).
The entire outside area of the upper tube (28 cm2), is exposed to CR-39. This is 62 times larger than the area covered in the last experiment. Likewise, the duration of the electrolysis is nearly three times longer. Therefore, my chance of observing particles emerging from the tube (I observed their tracks in the last experiment) is much higher now than before. And about 20 cm2 of the exposed CR-39 area inside the tube should reveal particles that Oriani observed inside the electrolyte.
Labeling of CR-39 pieces:
1) Chips A, B and BB will tell me if the outside wall of the tube, where tracks were discovered in my first experiment (see the unit #192), is still active when the this second experiment started.
2) Chip BBB is my background control sample.
3) Chips C and Pcrossed were in the air below the cathode during the entire 202.5 hrs of electrolysis. The chip C was looking at the Ni cathode (with its unlabeled side) while the chip Pcrossed was looking at the chip C from below. The labeled side of the chip Pcrossed is looking down toward a wooden cylinder supporting it.
4) Chips I and J were a pair making a cover above the cell. Chip I was looking down to the rising vapors (with its shinny side); The shiny side of the chip J was also looking down, thought the chip I. The labeled sides of both I and J were looking up. Both of these were used during the entire 202.5 hrs of electrolysis.
5) Chips D and M, both large, stand along the vertical glass wall of the tube. Chip D touches the glass with its shinny side, chip M touched the chip D with its shinny side. Both of these were used during the entire 202.5 hrs of electrolysis.
6) Chips E and N, both large, stand along the vertical glass wall of the tube. Chip E touches the glass with its shinny side, chip N touched the chip E with its shinny side. Both of these were used during the entire 202.5 hrs of electrolysis.
7) Chips H and O, both large, stand along the vertical glass wall of the tube. Chip H touches the glass with its shinny side, chip O touched the chip H with its shinny side. Both of these were used during the entire 202.5 hrs of electrolysis.
8) Chips G and L, both large, stand along the vertical glass wall of the tube. Chip G touches the glass with its shinny side, chip L touched the chip G with its shinny side. These two chips were removed before the step (i) of the electrolysis. In other words, they were collecting tracks only during the first 147.5 hours of electrolysis.
10) Chips F and K were suspended into the cell (crossed labeled down). F remained in the cell during the entire duration of the electrolysis (202.5 hours) while chip F was removed before the step (i), after 147.5 hours. Chip F was replaced by the chip S that remained in the cell for 50 hours (when the concentration of the electrolyte was increased and when larger currents started to be used).
11) Chips P, Q and PP were also used; I will describe their purpose only when it becomes necessary. were also standing along the tube walls.
12) Chips used after the electrolysis will be described later.
Yes, I know that ideally everything should be as constant as possible in a single experiment. Then one could change one parameter, for example, the current or concentration, and repeat the experiment. And that is what I might start doing when the goal will be to understand and to optimize. But for the time being the goal is to convince myself, and others, that the discoveries made by Oriani are real and worth focusing on. His philosophy is to scan over different currents and concentrations in order to approach 100% reproducibility. I am following this reasonable philosophy. What would be the purpose of changing one parameter at a time when outcomes of consecutive experiments are very different, even when controllable parameters are not changed?
Etching, observations, reflections, etc.
1) The figure below shows tracks due to alpha particles from an 241Am source. The chip, etched at the same time as that shown in Figure 3, was dirty. But, as one can see, dirt, scratches and other surface defects can easily be distinguished. The lower left corner is the chip boundary. Ambiguities in tracks counting are minimized when chips are handled carefully, and when they are washed after etching.
2) Without ending the electrolysis I removed three large CR-39 chips, K, G and L (after 147.5 hours) and etched them. The area of each chip is about 5 cm2. The chip K, that was suspended into the cell, was at once replaced by a fresh chip S. The average densities (based on random sampling of fields), were between 300 and 700 tracks per cm2 The nominal background density is about 10 tracks per cm2. The distribution of tracks was found to be clearly nonuniform. Clustering of tracks is illustrated in Figure 3. It is a photo of 18 tracks in the field of view whose area is 0.7 square millimeters. The four adjacent fields (of the same size, on the left, right, above and below) had zero tracks. Of the four diagonally nearest fields two had no tracks and two had one track each.
3) The electrolysis ended after 202.5 hours and all chips were etched. During the last 50 hours the concentration of the electrolyte was increased and currents up to 0.7A were used (instead of the up to about 0.35A before). The cathode was removed and sandwiched between two CR-39 chips. Likewise, chips were applied to the anode and to the electrolyte removed from the cell. Will these control chips also display particles, after I etch them in several days? I will let you know.
4) Chip S (that replaced the chip K inside the cell) was found to be covered with more particles (also clustered) than the chip K. More specifically, the average track density on two surfaces of the chip K (after 147 hours a accumulation) was about 520 tracks per cm2 (or 3.5 tr/cm^2 per hour). For the chip S, on the other hand, the average track density on two surface (after 147 hours a accumulation) appears to be at least two times higher. That seems to indicate that using more concentrated electrolytes, for example 0.5 M or above, and larger currents, is desirable.
5) And what about the tracks on chips D, E and H that were facing the glass walls of the tube? Each of these chips revealed clustering of tracks, similar to those shown in Figure 2. The same was seen on the chip Q that was used to replace the chip G. Facing this situation I am inclined to anticipate that anomalous tracks are likely to be 100% reproducible in setups similar to that shown in Figure 1. Please write to me <firstname.lastname@example.org> about your own attempts to replicate Orianis experiments; I will append your message to this webpage. Let me add, however, that quantitatively, results are not yet consistent. Additional experiments, preferably performed in different laboratories, are needed. The topic is too big for one or two people; your help will be highly appreciated.
6) As you may recall, my first experiment (see the unit #192) failed to confirm presence of nuclear particles in the air outside the cathode. Were I able to detect such particles in this experiment? The 1 cm2 chip, placed below the cathode, did record 28 particles in 202 hours of electrolysis . The method I am using is not appropriate for making decisions about very low recording rates. I do not know why the average recording rate was much higher in the experiment performed at Minneapolis (see the unit #188).
! ! ! P.S. (12/30/2004) ! ! !
Please suspend your judgment about the preliminary results described above. I just discovered that something alpha-radioactive might have been sporadically deposited on some of my CR-39 chips, when they were etched in the hot solution of NaOH. The entire experiment must be repeated, after the source of the contamination is identified and eliminated. I still believe that what I wrote above will be confirmed, at least qualitatively. But how can I be certain about this now, after discovering a lot of tracks on my both blank control samples? More about this later.
7) Tomorrow I will etch several control samples. The goal is to convince myself that blanks chips do not display any tracks after I stop suspending them from the thin telephone wires. I suspect that insulation of that wire released something radioactive. Perhaps it was uranium or thorium in a dye used for color coding. In most cases, but not always, the plastic insulation was was removed. In any case, I will etch the following chips:
Chip A: "blank" that was exposed to the air in the room for two weeks.
Chip B: "blank" that was also exposed for two weeks but in another area.
Chip C: "blank" that was exposed to the air in the room for about 0.5 hours only.
Chip D: was exposed (50 hours) to the plastic cover of the telephone wire.
Chip E: was exposed (50 hours) to the copper of the telephone wire.
Chip F: was exposed (10 seconds) to alpha particles from 241Am (at one end only).
Chip G: was exposed (50 hours) to the electrolyte after the electrolysis.
Chip H: was exposed (90 hours) to the nickel cathode after the electrolysis (dry side)
Chip I: was exposed (90 hours) to the nickel cathode after the electrolysis (wet side)
Chip J: was exposed (90 hours) to the platinum anode after the electrolysis.
Chip K: was exposed (90 hours) to the inside glass wall after the electrolysis.
Chip L: was exposed (90 hours) to the outside glass wall after the electrolysis.
Chip M: was exposed (90 hours) to the black plastic holder of chips used in etching.
Chip N: was exposed (50 hours) to the blue plastic sleeves in the crown of hooks.
Hopefully, the first three chips will show no contamination in the air or in the etching solution. The next two will test my hypothesis that contamination came from the plastic cover and not from the copper wire. (But the hypothesis assumes that contamination was released at 70 degrees C, during the etching, while the plastic cover was exposed to the CR-39 at room temperature. The test might turn out to be nonconclusive.) The chip F is my usual calibration test, to make sure that etching itself was sufficient. It is convenient to have F available to recall the appearance of alpha tracks, when in doubt. The last eight chips will tell me whether or not the cell is ready for the next experiment. Hopefully, these eight chips will show about as many tracks per unit area as chips A and B.
Yes, a lot of tracks were found on the chip D while the chip A had at most 3 tracks per square cmentimeter. I was lucky; the test was conclusive.Finding a source of weak contmination in a system made from many different materials can be a formidable task, unless the source is strong enough for a simple Geiger counter.
The more exciting, and puzzling, are huge numbers of tracks on chips H and I. Why did I not see tracks below the dry nickel cathode during the 202 hours of electrolysis? Why did I see a lot of them in 90 hours immediately after the electrolysis? There are only two explanations of this, as far as I can say: (a) Particles producing tracks were stopped in 6 mm of air (before reaching the CR-39) and (b) the foil started emitting particles after the current was turned off (or shortly before that). The first explanation is in conflict with the experiment i performed with Oriani, and with his subsequent experiments; the distance of 6 mm was chosen to match his distance. The second explanation is hard to accept but that is a matter of psychology, not physics. More about all this later.
I just started another accumulation of tracks from the used nickel cathode (another set of chips H and I) and from the glass wall (another set of chips chips K and L). Will I confirm Orianis observation that the rate of tracks accumulation is decreasing in times? Will this decrease be exponential? What will the half-life be? That remains to be seen.
The second accumulations mentioned above ended today and third accumulations started, for both nickel and glass. Oriani sent me his numbers of tracks/cm^2 per hour. They are consistant with the half-life of about 10 days. Will my accumulations confirm this? I looked at information about daugthers of radon and thoron. Nowhere could I see the half-life close to 10 hours.
Here is a trivial problem: Knowing the half-life of a radioactive isotope calculate how many atoms must be present to emit 100 particles per hour (Activity = 100 per hour)?
T = 10days = 240 hours ---> lambda = ln2/T = 0.69/240 = 0.029 per hour
A=lambda*N ---> N = A / lambda = 100/0.029 = 34624 atoms.
This is an exceedingly small number of atoms. A piece of dust, I suppose, can be expected to contain that many atoms of any element of the periodic chart. Yes, I know, it is too early to speculate that we are dealing with some kind of induced radioactivity. The only thing we know is that charged nuclear particles are present, even after the electrolysis, and that the average rate of emission, initially on the order of 100 per hour (in all directions) decreases it time. I have no idea what can cause this, except a radioactive substance.
My results (first post-electrolysis analysis, called experiment #3):
Chip A: Blank Only two or four tracks per square centimenter.
Chip B: another blank, but with 300 tracks/cm^2. Perhaps the metal box in which it was kept (?) contained something. In any case, this translates to 3.3 tracks/cm^2 per hour. I am still learning; a blank control chip must be handled in the same way as other detector chips, except for the electric current. Next time I will place it into the electrolyte together with the platinum wire, and the scraps of my nickel foil.
Chip C: another blank, clean as A above.
Chip D:: plastic cover over the copper wire. On the average 110 tracks per 0/044 cm^2. This translates into 50 tr/cm^2 per hour. The spiral pankake of wire was placed on the top of a chip for 90 hours. That is very high recording rate.
Chip E:: Copper wire. Some tracks were recorded in 90 hours.
Chip F: 241Am tracks are a large and easy to identify. Etching time was just right.
Chip G: Chip placed into the electrolyte for 50 hrs. About 2 tracks/cm^2 per hour.
Chip H: Chip on top of DRY nickel for 90 hours after the electrolysis 23.1 tr/cm^2 per hour. This is comparable to what Oriani observed. That is my first post-electrolysic exposure; two more will be etched and analyzed in three or four days. But Oriani also saw tracks accumulating diring the electrolysis. Why did I not see them? That is a big puzzle.
Chip I: Chip on top of WET nickel for 90 hours after the electrolysis. 17.7 tr/cm^2 per hour. This is also comparable to what Oriani observed.
Chip J: Chip on top of the anode (spiral platinum pancake) for 90 hours after the electrolysis. 5.4 tr/cm^2 per hour. That was a surprize. My wire was not new; I will ask the electrochemist who gave it to me what was this wire used for before. In any case, I washed this wire and then kept it in the 1 M solution of HCl for 24 hours. Do I have to start wearing gloves while handling the cell components? I will ask Oriani if he looked for particles emitted from the anode. Chip A:
Chip K: Chip exposed to the inner (wet) surface of glass for 90 hours after the electrolysis. 18.3 tr/cm^2 per hour. Hmm, nearly the same as from the cathode. Is it a pure coincidence? The back side of that chip (exposed to air) had 0.9 tr/cm^2 per hr.
Chip L: Chip exposed to the outer (dry) surface of glass for 90 hours after the electrolysis. 15.9 tr/cm^2 per hour. Hmm, nearly the same as from the cathode. Is it also a pure coincidence?
Chip M: Some tracks but not many.
Chip N: Some tracks but not many.
Experiment #2 (tracks collected during the electrolysis) cannot be trusted, as far as emission from the glass walls was concerned. That is because I was not sure which large chips were suspended from the insulated wire during etching. But this should not prevent me from saying that the average recording rates from glass (about 16 tracks/cm^2 per hour) were observed after the electrolysis. In other words, the glass situation is as puzzling as the nickel situation; the average rate of the recording after the electrolysis was higher than during the electrolysis (2.5 tracks/cm^2 per hour). How can it be? I also do not know why my average recording rate, below the cathode and during the electrolysis, was negligibly small in both experiments. This conflicts with what I observed in Minneapolis. It also conflicts with nearly 30 tracks/cm^2 per hour that Oriani recorded in the most recent experiment. The first time I failed to observe tracks below the cathode during the electrolysis was when the distance between the detector and the cathode was 1 mm. The second time I failed to see a lot of tracks was when the distance was 6 mm, the same as in OrianiÕs experiments.
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