I found extremely interesting the paper on some fundamental “Questions About Mechanisms and Materials for LENR”, appeared in the issue 118 of Infinite Energy magazine and written by David J. Nagel, an American distinguished scientist whose current research centers on “Lattice Enabled Nuclear Reactions” (LENR). He is also the founding CEO of NUCAT Energy LLC, a company that provides various consulting and educational services for LENR.
Here’s a brief summary from his 14 pages article:
1) Is there only one, or more than one, basic physical mechanism(s) active in LENR experiments to produce the diverse measured results?
“In LENR experiments have been measured: (1) large thermal power releases and high energy gains; (2) output processes as fast as microseconds; (3) nuclear products ranging from tritium and helium through elements with intermediate masses to heavy elements; (4) fast particles, especially neutrons, charged particles and energetic photons; and (5) other effects such as emission of radio-frequency and infrared radiation and sound. The lack of many correlations between different experimental outputs from LENR experiments would seem to favor the operation of two or more fundamental mechanisms for LENR, either simultaneously or sequentially”.
2) Is excess heat from electrochemical loading and gas loading experiments due to the same basic mechanism(s)?
“It is possible that different mechanisms are active in these two major approaches to creating conditions that result in LENR. It might be possible to address this question by the use of the same materials in both types of experiments. Some cylindrical rods of some material that are coated, several at a time in the same equipment, with a thin film of a material conducive to producing LENR, maybe containing Pd or Ni, could be used as electrodes in electrochemical experiments and others put into gas loading experiments. Comparison of the results obtained with the two methods of loading might provide an answer to this question, although that is not the only potential outcome. It remains possible that the same mechanism(s) occur for both methods of loading, but differences in the two techniques would lead to divergent results”.
3) Do LENR occur exclusively as individual uncoupled events, or is it possible to have cascades of LENR, in which a reaction makes more likely the occurrence of more LENR?
“During energy production by nuclear fission, the proximity of fuel nuclei is necessary, if neutrons released by prior reactions are to be efficiently captured to produce further fissions. That leads to the question of whether or not similar effects might operate during the production of energy by LENR. That is, are cascaded or chain reactions operable during production of heat by LENR? There has been very little discussion of this possibility in the field to date. The answer to this question will ultimately depend on understanding of the basic mechanism(s) that produce LENR. There is indirect experimental evidence for the nearly simultaneous occurrence of numerous LENR in small spatial regions. However, that evidence alone does not indicate whether the reactions are independent of each other or occur in causal sequences”.
4) Is the excess heat due entirely or only partially to nuclear reactions, and, if partially, what other mechanism contributes to the heat output?
“It is conceivable that, under some conditions, all of the excess energy is due to nuclear reactions and, under other conditions, little of it is nuclear. Intermediate situations could also exist. Fleishmann and Pons thought that the only alternative explanation for the excess heat found in their experiment was nuclear reactions. However, there was and remains the possibility that there is some entity between nuclei and atoms in both size and energy, which can be formed with the release of energy, that is, without requiring nuclear reactions. Many theorists have postulated ‘compact objects’ (for example, the hydrino postulated by Randell Mills), the formation of which would yield eV to keV-scale energies, rather than nuclear MeV energies. Such entities supposedly involve one of the hydrogen isotopes as nuclei and also orbital electrons. Because of their small size and electron shielding, the protons or deuterons at the center of these objects can move closer to other nuclei in materials, which increases the probability of later true nuclear reactions”.
5) What are the keys to making and maintaining materials that produce excess heat regarding both composition (notably impurities) and structure (vacancies, dislocations, cracks, etc.)?
“It is thought by many people that subtle, but critical variations in materials within LENR experiments are what make production of excess power challenging, and also account for variations in both reproducibility and output power. It was realized over 15 years ago that low level impurities could produce modest excess powers in LENR experiments, if the impurities were reactants. Even if impurities are not actually fuel, they might be needed to produce nuclear active regions in which LENR can occur. Very many physical and chemical processes have been employed to prepare the interior bulk and exterior surfaces of materials for LENR experiments. So, development of a quantitative and predictive theory for production of nuclear active regions might resolve this question. However, it is also possible that only very careful parametric experiments, in which key factors are both varied willfully and characterized in detail, will suffice to solve the materials riddle”.
6) The location of LENR has important implications. Do LENR occur on or near surfaces or in the bulk of materials or at any locations on or in a material?
“It matters greatly, both scientifically and practically, if LENR occur on or very near to surfaces of materials, in their bulk or in both types of locations. Surface sites, including cracks that extend to the surface, are readily accessible from the surrounding liquid or gaseous atmosphere. There is substantial empirical evidence of varying quality which indicates that LENR occur on or near the surface of solids. A systematic study of Pd material characteristics in relationship to their ability to produce excess power was conducted by Vittorio Violante and his coworkers at the Italian ENEA laboratories in Frascati, showing that surfaces with structures in the sub-micrometer (nanometer) scale favored the production of LENR power. However, the case for where LENR occur is certainly not closed. If LENR occur on surfaces, it will be easier to bring reactants together and to remove products compared to reactions occurring within materials, and it will also be easier to reconstitute nuclear active reactions on the surfaces of materials”.
7) Are nano-scale structures or particles sizes necessary for occurrence of LENR?
“We cited some evidence just above for LENR occurring mainly on or near the surfaces of materials. If that is the dominant situation, then nanometer-scale structures could be fundamental to the occurrence of LENR. That is due to the fact that the surface and nearby regions on materials are generally on the order of 1 nanometer or less in thickness. As the size of material particles decreases toward the nanometer-scale, the surface-to-volume ratio increases. There is a significant body of research on LENR that involves particles with dimensions on the order of nanometers. It might be necessary to have structures with nanometer scales in two or three dimensions, in order to cause LENR. There has been some work published on the production and use of surfaces that have nanometric structures on or embedded in them prior to experiments. Such surfaces can be made by a wide variety of physical and chemical techniques”.
You can read the full article “Questions About LENR: Mechanisms and Materials” here.
DAVID J. NAGEL graduated Magna Cum Laude in Engineering Science. He has received an MS degree in Physics and a PhD in Materials Engineering. After graduating, Nagel worked as an officer in the US Navy and in 1990 joined the civilian staff of the US Naval Research Laboratory (NRL). He is currently Research Professor at The George Washington University, in the Department of Electrical and Computer Engineering.