Monday, March 10, 2014

CSI´s Dave Thomas: Thermodynamic Size Effect Fraud

Updated April 21/2014.

Dave Thomas is a well known pseudo-skeptic at the JREF 9/11 forum, being the president of  New Mexicans for Science and Reason and a fellow of the Committee for Skeptical Inquiry (CSI).

I recently wrote an article about Mr. Thomas´ YouTube pseudo-science and his amusing failures to form iron spheres by burning steel wool and paint. The latter "spheres from paint" video was supposed to be a triumphant response to an essay that debunked his earlier "steel wool" video, but instead it demonstrated another invalid and unpublishable experiment. Mr. Thomas also posts false conclusions without resorting to YouTube, as his NMSR webpage makes evident: 
The answer to the mystery of the microspheres - "Iron melts only at temperatures far higher than possible in normal fires, so how could microspheres have possibly been formed on 9/11?" – is simply that very small metal particles have much lower melting points than their bulk material counterparts (around 900 o C for iron nanoparticles, as opposed to 1535 o C for bulk iron). This is called the "thermodynamic size effect."
Since Dave Thomas confirmed in his "spheres from paint" video that he knows the pertinent part of our essay, he has no excuse for ignoring the fact that it also debunks the above statement:
Dave Thomas has proclaimed that the notion of melting-point depression explains the molten state of the spheres, because nano-sized particles can have a lower melting-point. But this phenomenon only applies to particles that are much smaller than the iron particles in the chips and the observed spheres...
Update: Dave´s colleague on the JREF forum has pointed out that there was no commercial supply of iron particles that small in 2001, so Dave´s suggestion on his NMSR web that the WTC buildings had potential sources all over the place is patently absurd:
"The towers contained thousands of computers and electric gadgets. Wires and filaments and meshes from electronics, as well as thin rust flakes and other small iron particles, could all have easily been made into microspheres during the WTC conflagration."
An honest researcher would have displayed sources to back up his theory to begin with. There may have been some "thin rust flakes" present at the WTC, but a rust flake is "...nonreactive with most chemicals and is heat-stable up to its melting point of over 1,500°C." So rust flakes are not only unlikely to ignite in a fire, they are unaffected by the "thermodynamic size effect". This is very unfortunate because this is yet another debunking of RJ Lee´s rust-flake story, which Dave also displays on his page.

The "thermodynamic size effect" only applies to particles that are smaller than 50 nanometers and is not significant until the particle size drops well below 25 nm, so implying that only 900° C is needed without providing some evidence for the presence of iron particles below 25 nm is a blatant display of dishonesty. Harrit´s paper does in fact describe the rhombic shaped iron grains present in the red/gray chips as "consistently 100 nm in size". No-one has even proposed a hypothesis for the possible presence of iron or iron-oxide grains smaller than 25 nm in neither the red nor gray layer of the chips - or any other WTC material - let alone physically identified even a single grain that small. This is why Dave Thomas is stuck making flatulent YouTube videos instead of publishing in reviewed journals. 

Figure 1. A normalized melting curve for gold as a function of nanoparticle diameter. The bulk melting temperature and melting temperature of the particle are denoted TMB and TM respectively. Experimental melting curves for near spherical metal nanoparticles exhibit a similarly shaped curve.