Posts by NEPS*NewEnergy

In his October 2001 paper, Ichimaru also said "In addition, we recognize that the reduced mass .. . and the corresponding atomic-mass number ... take on the smallest possible values (Eq.-) .... Wave-mechanical effects on penetration through the Coulomb barriers screened by electrons, essential for prolific nuclear reactions, can thus be maximally exploited in these circumstances.

A recent post (#234) indicated that "A reason for including the (p, d) reaction is that it should occur more easily in a cold fusion environment than (d, d) reactions. This is discussed in "Radiative Proton-Capture Nuclear Processes in Metallic Hydrogen," by Setauo Ichimaru, Physics of Plasmas, vol. 8, no.10, pages 4284-4291, October 2001." This was followed by another post (#238) that indicated "owing to strong screening by K-shell electrons, if the densities ⩾60–80 g/cm3, the pressures ⩾7–12 Gbar, and the temperatures just above solidification." Please note that such high densities and pressures might not be required if screening were caused for other reasons, such as what is described in “A Theoretical Model for Low-Energy Nuclear Reactions,” by K.P. Sinha, Infinite Energy, vol. 29, pages 54-57, January/February 2000.

A reviewer indicated above that in cold fusion experiments there was "little evidence of significant 2.2 Mev Gamma photons ..or neutrons". Gamma rays with an energy of 2.22 MeV could be expected from (n, p) reactions, i.e., from neutron capture by protons (e.g., in hydrogen gas or water). But, heavy water used in cold fusion experiments is also a neutron moderator for some other applications. Neutrons, if they were produced by (d, d) fusion, might have been slowed down or moderated by heavy water near the center of the cold fusion experiments. The lower-velocity neutrons may not have been able to traverse the internal container containing heavy water to reach water (H₂O, containing protons) in the calorimeter.

A reason for including the (p, d) reaction is that it should occur more easily in a cold fusion environment than (d, d) reactions. This is discussed in "Radiative Proton-Capture Nuclear Processes in Metallic Hydrogen," by Setauo Ichimaru, Physics of Plasmas, vol. 8, no.10, pages 4284-4291, October 2001.

WRT item “j”, (need for sufficient number of reaction sites), it is also necessary to consider the different “types” of nuclear reactions that might be possible in the cathode, along with their individual probabilities. For example, some cold fusion researchers have assumed that helium and energy produced may be due to lithium in the electrolyte of liquid electrolysis experiments. The idea is that the helium and energy could be from neutrons (or protons neutralized with electrons) transmuting lithium into beryllium that then could break apart into helium. Otherwise, at least nine (9) different reactions need to be considered as potentially operative in a cold fusion generator. The (p, d) fusion reaction is a commonly recognized step in the proton-proton solar fuel cycle. Energy is provided by gamma radiation developed in forming helium-3. Then, (d,d) fusion can be described by three competing paths producing energy along with protons, neutrons, tritium, helium-3 and helium-4. The (d, T) fusion reaction produces energy along with neutrons and helium-4. Gamma radiation with energy greater than 2.22 MeV from these fusion reactions can cause deuterium to disintegrate back into protons and neutrons. Neutron capture by protons (e.g., in hydrogen gas or water) can produce deuterons and gamma radiation. Neutron scattering from deuterium, by comparison, has a low probability for neutron absorption. Neutron velocity can be moderated in the scattering process. And, neutron absorption in helium-3 can produce energy along with tritium and protons.

About 2 x 10¹⁷ helium atoms per second might be anticipated from 200 kW. These need to be removed so that additional hydrogen and/or deuterium gas can be added, and operation of the system continued for long periods of time. A year of continuous operation at 2 x 10¹⁷ nuclear reactions per second would produce 6 x 10²⁴ helium atoms (10 moles) that occupy about 200 liters at standard temperature and pressure. A capability to remove incremental and pre-determined quantities of helium might also help balance pressure-related, variable operating conditions within the reactor. Helium is also an irreplaceable natural resource of limited extent. Collection and storage of helium can result in a profitable resource due to its commercial uses.

The above post posits an idea for practical industrial systems that helium-4 and helium-3 produced by the cold fusion process must be able to be extracted from, or at least leak out of, the cathode, enabling the system to operate for much greater periods of time than systems where helium is not removed. Systems that produce kilowatts of energy must enable greater than 10¹⁶ nuclear reactions per second, assuming that each reaction nets several MeVs. Helium gas molecules can be anticipated to be produced at approximately this rate. Helium permeable materials (zirconia, fused silica and silica glass) have been investigated in other applications to enable extraction and recovery of helium from a mixture including other gases, such as hydrogen and deuterium. Sufficiently high diffusion rates are possible due to helium’s small, monoatomic molecule diameter. Reference, for example, “The Diffusion of Hydrogen and Helium through Silica Glass and Other Glasses,” by G.S. Williams and J.B. Ferguson, Journal of the American Chemical Society, vol. 44, pages 2160-2167 (1922), that discusses gas permeability through these materials versus its pressure and temperature.

With regard to (WRT) item “j” on sufficient reaction sites in the cathode, another important consideration is that helium produced by the cold fusion process must be able to be extracted, or at least leak out, for a practical industrial system. This will probably be necessary to allow additional hydrogen and/or deuterium to be added. Cold fusion scientists have been able since the early 1990s to demonstrate experimentally that 0.6 x 10¹² to 4 x 10¹² helium atoms produced per second correlate with a watt of excess power (ref. “Correlation of Excess Power and Helium Production during D₂O and H₂O Electrolysis using Palladium Cathodes,” by M.H. Miles et al., Journal of Electroanalytical Chemistry, vol. 346, page 99+, 1993; and “Correlation of Excess Enthalpy and Helium-4 Production: A Review,” by M.H. Miles, 10th International Conference of Cold Fusion, 2003). Additional amounts of helium may have been produced but not measured if trapped inside their cathodes. Another consideration is that cooling mentioned above for one of the cathode surfaces must be controlled accurately so that the cathode is not cooled below its Debye temperature.

For item j , some related technical references are, for example: “Hydrogen in Metals II, Application Oriented Properties,” by G. Alefeld and J. Volkl (ed), Springer-Verlag, Berlin, 1978. See pages 166-169 and 180-182 in paper on “Metal-Hydrogen Systems at High Pressures,” by B. Baranowski, and pages 274-5, 277, and 300 in paper on “Electro- and Thermotransport of Hydrogen in Metals,” by H. Wipf; and, “Fast Ion Transport in Solids,” by W. van Gool (ed), North Holland Publishing Company, 1973. See pages 249-262 in paper on “Cation Diffusion and Conductivity in Solid Electrolytes,” by Ryoichi Kikuchi.

Now consider item “j”, the need for sufficient number of reaction sites in the cathode, i.e., from the above list of system concepts/parameters. (Readers continue to be encouraged to suggest their own “one liner" engineering concepts/parameters.) Deuterium and/or hydrogen flux (the number of atoms per unit area per second) through reaction material in the cathode is affected by drift due to an electric field and diffusion due to a temperature gradient. An electric field is produced by a potential (e.g., 1000 volts, direct current) supplied between the anode and cathode, but is reduced in magnitude within the reaction material, in the same manner as for dielectrics used in capacitors. The electric field in the reaction material is expected to decrease with loading. The temperature gradient is produced by heating one of the cathode surfaces and cooling the other surface. Another consideration is that some deuterium or hydrogen can be expected to leak out of the cathode, and the amount of loading achieved will depend to a large extent on how well leakage can be prevented. The localized concentration of deuterium or hydrogen can, therefore, be expected to move about in the reaction material, and reaction rate will not be uniform across the volume of the reaction material (or the cathode). As a result, a long cathode with a large surface area is expected to be much better than a thick one.

As part of item “b” (inner workings of gaseous cold fusion systems), the use of microwaves was mentioned as a possible method during start-up to enable ions to move between the anode and cathode. A microwave antenna (or coupler) would be used to irradiate the volume of hydrogen and/or deuterium gas between the anode and cathode with (e.g. 2.54 gigahertz) microwave radiation, so as to increase the electron to gas molecule collision frequency, partially ionizing the gas and enabling polarized movement of gas ions toward the cathode. Reference “The Large Volume Microwave Plasma Generator: A New Tool for Research and Industrial Processing,” by R.G. Bosisio, Journal of Microwave Power, vol.7. no.4, 1972, and “Microwave Discharges: Generation and Diagnosis,” by Yu.A. Lebedev, 25th Summer School and International Symposium on the Physics of Ionized Gases (SPIG 2010), Journal of Physics: Conference Series 257 (2010), January 2010.

The recent post from RobertBryant appears to complain that some of the words "is an invention of NEPS rather than of Sears and Zemansky", whereas what was written by NEPS is actually consistent with what is stated in the text. Clearly, the force on a charged particle in electric (E) and magnetic (B) fields is given by: F = q (E + v X B).

The NEPS post said "The discussion in Sections 31-1 and 31-2 of Sears, Zemansky and Young indicates that a point charge (e.g., one of the deuterium ions) moving with velocity (v) produces magnetic field lines that are circles with centers along the line of the velocity. Due to symmetry of the circular magnetic field lines, a point charge (e.g., a second deuterium ion) lying on the line of the velocity should not be deflected. In addition, the cross product of electric and magnetic fields EXB should keep the ions centered along the line of the velocity. Collision can, therefore, be expected." We would be pleased to hear comments on the manner in which two oppositely charged ions that are moving in a straight line, but in opposite directions, might behave.

Additional understanding of item “b” about the inner workings of gaseous cold fusion systems may be obtained by studying how hydrogen thyratrons operate, even though pressure in those tubes is typically much lower than an atmosphere. (Reference pages 112-134 in “Basic Electronics,” by Lawrence A. Johannsen and Russell P. Journigan, Delmar Publishers, Inc., Albany, New York, 1963). Hydrogen gas thyratron tubes with extremely rapid firing times have historically been used in radar applications. Ionized gas (e.g., between the anode and cathode) contains a mixture of electrons, positive and negative ions, and the ordinary neutral gas molecules, as described in an earlier post. This “plasma” extends from the anode to cathode, and acts as the conduction path in the tube. Once ionization takes place, by a voltage that exceeds the ionization potential of the gas, the current is then able to rise quickly to its maximum. A gaseous tube cannot limit this current by itself. An outside load resistance is, therefore, required to limit the electric current to a value within the design limitations of the tube. Or, some other type of device in series with the tube is required to produce a voltage drop that will limit the current as soon as conduction has started. As a result, the anode-cathode voltage needs to be limited so that operation is below what is called the “Townsend discharge” region in a graph of current versus voltage.

In response to RobertBryant's most recent post on magnetic fields from moving charges, please note that deuteron velocity was estimated in an earlier NEPS post.

In a new post, Robert Bryant continued to show interest in the discussion about magnetic fields produced by movement of charges in Sections 31-1 and 31-2 of Sears, Zemansky and Young. This understanding is very important in understanding the manner in which two ions (one positive and one negative) might be able to be accelerated towards each other. First, consider the magnetic field produced by a moving positive charge, such as a deuteron with no electrons around it. The directions of the magnetic field is given by the right-hand rule: Grasp the velocity vector ‘v’ with your right hand, so that your right thumb points in the direction of ‘v’; your fingers then curl around the line of ‘v’ in the same sense as the magnetic-field lines. Then, consider the magnetic field produced by a negative charge, such as a deuteron with two electrons around it, moving in the opposite direction to the first charge. The direction of its magnetic field can also be determined by applying the right-hand rule, but remembering that the magnetic field lines will be in the opposite direction due to the negative charge. As a result, both magnetic fields will be in the same direction and will overlap as the two ions approach each other.

A reviewer recently had a question about the statement that "Much higher gas pressure is expected to be required for operational devices." Some successful experiments have used relatively low pressure (about 1 atm. for example). Ed Storms' briefing at ICCF23 is very instructive regarding success that is possible when externally heating the cathode (e.g., above 350 ^oK). It might be possible to backfield the cells with gas at higher pressure to confirm that even better results could then be obtained.

Item “b” has to do with the inner workings of gaseous or gas-based cold fusion systems. These systems contain (partially) ionized hydrogen and/or deuterium gas residing between the anode and cathode. This discussion is important, as liquid electrolysis systems will be difficult-to-impossible to scale-up and industrialize. At start-up, ionization can be provided via a microwave antenna configured to facilitate ion transport between the anode and cathode. Radiation produced by cold fusion reactions in the cathode can be expected later to help ionize the gas. In a gas-based system, molecules of gas impacting the surface of the cathode will travel at high velocity related to temperature (thermal kinetic energy). Gas pressure on the surface of the cathode is due to the numbers of gas molecules and their kinetic energies. Average velocity of the molecules can be easily calculated if this were of interest. The average density of molecules at any instant can be calculated from the ideal gas law, PV = n RT, where n is the number of moles of gas (1 mole = 6.02 x 10²³ molecules) and R is the universal gas constant (R = 0.082 liters-atmospheres/moles-^oK). If the system were operated at 10 atmospheres of pressure and 456 ^oK (183 ^oC, the Debye temperature for nickel), then one liter of the gas would contain 1.6 x 10²³ molecules. A volume of one cubic micron (10^-15 liter) adjacent to the cathode’s surface would contain 1.6 x 10⁸ molecules. These will need to penetrate through the cathode’s surface and flow into the reaction material’s microscopic cracks, crevices and defects to support the cold fusion reaction process. Much higher gas pressure is expected to be required for operational devices.

WRT item “b”, supporting data for gas-based systems can be found in a great number of scientific works since the late 1800s regarding electrical conduction through hydrogen gas. For example, see the paper, “On the Electrolysis of Gases,” by J.J. Thompson, Proceedings of the Royal Society, vol.58, no. 350, pages 244-257, June 1885, and pages 270-274 and 293-294 in the “Theory of Gaseous Conduction and Electronics,” by F.A. Maxfield and R.R. Benedict, McGraw Hill. 1941. In addition, note that high voltage breakdown or avalanche discharge through the gas is not desired. The Paschen curve for hydrogen and the Townsend criterion can be used to ensure that sufficiently low anode-to-cathode voltage along with high gas pressure is used to prevent breakdown. See pages 188-190 in “Introduction to Electrical Discharges in Gases, by S.C. Brown, John Wiley and Sons, 1966.

With regard to item “b” in the above list of system concepts/parameters, “deuterium gas loading in gaseous systems can be just as operative as electrolytic loading for liquid systems,” consider the physical similarities between gas-based and liquid-based LENR experiments. Each contains cathodes where reactions can be made to occur, anodes, electrolytes (i.e., gas or liquid), and direct (dc) drive currents. A liquid-based system is concerned with anions and (e.g., D⁺ and/or H⁺) cations, their movement in a liquid electrolyte and cathode interactions. Gas-based concepts, by comparison, are concerned with mechanisms that can form positive ions from (e.g., deuterium and hydrogen) gas molecules, their movement to the cathode and cathodic interactions. Several ion forming mechanisms (elastic, excitation, ionization) can be considered, but the most important is due to collision of thermal electrons with gas molecules. Ionization cross sections vary in a non-linear manner. Energies of scattered electrons are frequently increased in the scattering process. The resulting mixture can contain many different species of ions and molecules that interact with various cross sections as described in “Cross Sections and Swarm Coefficients for H⁺, H₂⁺, H₃⁺, H₂, and H^- in H₂ for energies from 0.1 eV to 10 keV,” by A.V. Phelps, Journal of Physical Chemistry, Reference Data, vol. 19, no 3, 1990.

An early gas loading concept is discussed in patent application WO95/20816, “Energy Generation and Generator by Means of Anharmonic Stimulated Fusion,” by S. Focardi et al., August 3, 1995. The application discusses methods to initiate cold fusion reactions including the use of electricity through a high-temperature coil to load the reaction material as well as heat it above its Debye temperature.