Eppur si fonde!

Mi è stata segnalata una breve rassegna di letteratura scientifica peer reviewed sulla fusione di atomi di Deuterio a temperatura ambiente con conseguente produzione di neutroni. 

Ops, ma allora gli infaticabili "scienziati della domenica" che da anni ribadiscono e spiegano, pazientemente e inesorabilmente, come la fusione nucleare possa avvenire solo ad altissime temperature nelle stelle o - un giorno - nei tokamak, cosa ci raccontano?

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Journal of Applied Physics (2005) 97, 074109: Electron and positive ion acceleration with pyroelectric crystals di Jeffrey A. Geuther and Yaron Danon. "The phenomenon of pyroelectric electron emission has been employed to develop miniature x-ray sources, such as the Cool-X by Amptek (www.amptek.com/coolx.html). The source strength of a pyroelectric x-ray generator is dependent on the emitted electron energy and current. Similarly, the source strength of a pyroelectric neutron generator will be dependent on the energy and production rate of deuterium ions in the fill gas. This paper summarizes our results in experiments directed toward creating high-energy electrons and positive ions with a pyroelectric source. Single-crystal sources are shown to produce positive ions with energies of up to 98 keV and electron energies of up to 143 keV. X-ray spectra are presented as proof that a paired-crystal source can increase electron energy to at least 215 keV. In addition, we offer independent verification of the “bunched” electron emission effect observed by."

Nature (2005) vol. 434, 1115—1117: Observation of nuclear fusion driven by a pyroelectric crystal di B. Naranjo, J.K. Gimzewski & S. Putterman. "While progress in fusion research continues with magnetic and inertial confinement, alternative approaches — such as Coulomb explosions of deuterium clusters and ultrafast laser–plasma interactions — also provide insight into basic processes and technological applications. However, attempts to produce fusion in a room temperature solid-state setting, including ‘cold’ fusion and ‘bubble’ fusion, have met with deep scepticism. Here we report that gently heating a pyroelectric crystal in a deuterated atmosphere can generate fusion under desktop conditions. The electrostatic field of the crystal is used to generate and accelerate a deuteron beam (>100 keV and >4nA), which, upon striking a deuterated target, produces a neutron flux over 400 times the background level. The presence of neutrons from the reaction D + D --> ³He (820 keV) + n (2.45 MeV) within the target is confirmed by pulse shape analysis and proton recoil spectroscopy. As further evidence for this fusion reaction, we use a novel time-of-flight technique to demonstrate the delayed coincidence between the outgoing alpha-particle and the neutron. Although the reported fusion is not useful in the power-producing sense, we anticipate that the system will find application as a simple palm-sized neutron generator."

Nano Today (2009) 4, 227—234:  Enhanced pyroelectric crystal D—D nuclear fusion using tungsten nanorods di Donald J. Gillich, Ranganath Teki, Travis Z. Fullem, Andrew Kovanen, Ezekiel Blain, Douglas B. Chrisey, Toh-Ming Lu, Yaron Danon. "Thin films of vertically aligned tungsten nanorods were used to enhance field ionization in pyroelectric crystal D—D fusion experiments resulting in increased neutron production. The tungsten nanorods were deposited on a single LiTaO₃ crystal using sputter deposition at glancing angles. The combination of a single tungsten tip with a thin film of nanorods on the face of the crystal yielded about four times the number of neutrons than did either a single tip or nanorods alone." 

Coursework for Physics 240, Stanford University, Fall 2010: Pyroelectric Fusion di Firas Abuzaid. "After the significant breakthrough in 2005, when researchers at UCLA introduced what's unofficially referred to as "tabletop fusion," fusion research, particularly research in pyroelectric fusion, is now on the rise. This breakthrough had enormous implications: by gently heating a pyroelectric crystal in a deuterated atmosphere, one can generate fusion under desktop conditions. Prior to that, attempts to produce fusion in a room temperature solid-state setting, including "cold" fusion and "bubble" fusion, have met with deep skepticism. Now, however it has been show that pyroelectric crystals have been shown to be useful materials for the production of low-cost, portable X-ray sources."

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Fusione piroelettrica... ma dove ne ho già sentito parlare? Ma certo,fu lo scorso mese di dicembre a Roma a Coherence 2012! Le slides presentate da Yogendra Srivastava: Neutron Production from Smart materials: Pyro and Piezo electrics.

E ne parla pure Wikipedia — http://en.wikipedia.org/wiki/Pyroelectric_fusion — ovviamente, però solo in lingua inglese: per noi Italiani, tanto per cambiare, nessuna voce che vada oltre la fisica del XX secolo.

22passi.blogspot.com: post n. 2151 (-71)