In 1988, Fleischmann and Pons applied to the United States Department of Energy for funding towards a larger series of experiments. Up to this point they had been funding their experiments using a small device built with $100,000 out-of-pocket.[31] The grant proposal was turned over for peer review, and one of the reviewers was Steven Jones of Brigham Young University.[31] Jones had worked for some time on muon-catalyzed fusion, a known method of inducing nuclear fusion without high temperatures, and had written an article on the topic entitled "Cold nuclear fusion" that had been published in Scientific American in July 1987. Fleischmann and Pons and co-workers met with Jones and co-workers on occasion in Utah to share research and techniques. During this time, Fleischmann and Pons described their experiments as generating considerable "excess energy", in the sense that it could not be explained by chemical reactions alone.[30] They felt that such a discovery could bear significant commercial value and would be entitled to patent protection. Jones, however, was measuring neutron flux, which was not of commercial interest.[31][clarification needed] To avoid future problems, the teams appeared to agree to publish their results simultaneously, though their accounts of their 6 March meeting differ.[32]
A pariah field, cast out by the scientific establishment. Between cold fusion and respectable science there is virtually no communication at all. Cold fusion papers are almost never published in refereed scientific journals, with the result that those works don't receive the normal critical scrutiny that science requires. On the other hand, because the Cold-Fusioners see themselves as a community under siege, there is little internal criticism. Experiments and theories tend to be accepted at face value, for fear of providing even more fuel for external critics, if anyone outside the group was bothering to listen. In these circumstances, crackpots flourish, making matters worse for those who believe that there is serious science going on here.[37]
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This was also the belief of geologist Palmer, who convinced Steven Jones that the helium-3 occurring naturally in Earth perhaps came from fusion involving hydrogen isotopes inside catalysts like nickel and palladium.[139] This led their team in 1986 to independently make the same experimental setup as Fleischmann and Pons (a palladium cathode submerged in heavy water, absorbing deuterium via electrolysis).[140] Fleischmann and Pons had much the same belief,[141] but they calculated the pressure to be of 1027 atmospheres, when cold fusion experiments achieve a loading ratio of only one to one, which has only between 10,000 and 20,000 atmospheres.[text 7] John R. Huizenga says they had misinterpreted the Nernst equation, leading them to believe that there was enough pressure to bring deuterons so close to each other that there would be spontaneous fusions.[142]
Cold fusion setups utilize an input power source (to ostensibly provide activation energy), a platinum group electrode, a deuterium or hydrogen source, a calorimeter, and, at times, detectors to look for byproducts such as helium or neutrons. Critics have variously taken issue with each of these aspects and have asserted that there has not yet been a consistent reproduction of claimed cold fusion results in either energy output or byproducts. Some cold fusion researchers who claim that they can consistently measure an excess heat effect have argued that the apparent lack of reproducibility might be attributable to a lack of quality control in the electrode metal or the amount of hydrogen or deuterium loaded in the system. Critics have further taken issue with what they describe as mistakes or errors of interpretation that cold fusion researchers have made in calorimetry analyses and energy budgets.[citation needed]
Cold fusion researchers (McKubre since 1994,[150] ENEA in 2011[94]) have speculated that a cell that is loaded with a deuterium/palladium ratio lower than 100% (or 1:1) will not produce excess heat.[150] Since most of the negative replications from 1989 to 1990 did not report their ratios, this has been proposed as an explanation for failed reproducibility.[150] This loading ratio is hard to obtain, and some batches of palladium never reach it because the pressure causes cracks in the palladium, allowing the deuterium to escape.[150] Fleischmann and Pons never disclosed the deuterium/palladium ratio achieved in their cells;[151] there are no longer any batches of the palladium used by Fleischmann and Pons (because the supplier now uses a different manufacturing process),[150] and researchers still have problems finding batches of palladium that achieve heat production reliably.[150]
In all cases the transmutation leads to the formation of 186Os (stable isotope) which is then transmuted to other nuclei. Though the same intermediate isotope is produced in Reactions (21, 22a, 22b) the rates of processes are distinctly different because of differences in cross-section of respective steps. Temporal evolution of the composition change for tungsten and W alloys under ITER and fusion power plant conditions has been calculated by Gilbert and Sublet [37]. Besides the main products, i.e. Re and Os, there are some quantities of tantalum, hafnium, hydrogen, helium and, in the case of a power plant reactor also platinum and iridium. It is predicted that in ITER after 14 years of operation there will be 0.2 (at.%) of Re in W, while after 5 years of reactor operation Re and Os will constitute around 10 (at.%) of the composition. The new alloy will also contain H, He and a large number of other species, such as Ta, Hg, Pt. Calculations for transmutation of other elements are in [38,39,40,41]. One expects that the change of chemical composition would not be uniform through the bulk because cross-sections change with the neutron energy loss by stopping in the lattice. It should also be stressed that activation is to be taken into account in the case of plasma edge cooling, especially when the use of heavy gases, e.g. Kr, is considered [41].
In the current work, T-joints consisting of 2.0 mm thick 2060-T8/2099-T83 aluminum-lithium alloys for aircraft fuselage panels have been fabricated by double-sided fiber laser beam welding with different filler wires. A new type wire CW3 (Al-6.2Cu-5.4Si) was studied and compared with conventional wire AA4047 (Al-12Si) mainly on microstructure and mechanical properties. It was found that the main combined function of Al-6.2%Cu-5.4%Si in CW3 resulted in considerable improvements especially on intergranular strength, hot cracking susceptibility and hoop tensile properties. Typical non-dendritic equiaxed zone (EQZ) was observed along welds' fusion boundary. Hot cracks and fractures during the load were always located within the EQZ, however, this typical zone could be restrained by CW3, effectively. Furthermore, changing of the main intergranular precipitated phase within the EQZ from T phase by AA4047 to T2 phase by CW3 also resulted in developments on microscopic intergranular reinforcement and macroscopic hoop tensile properties. In addition, bridging caused by richer substructure dendrites within CW3 weld's columnar zone resulted in much lower hot cracking susceptibility of the whole weld than AA4047.
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