Oystein
Penultimate Amazing
- Joined
- Dec 9, 2009
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Mark Basile's analysis of his own dust sample can be seen in this video, of which I provide a summary now:
http://www.youtube.com/watch?v=AJ7hXrmMRPc#!
According to the presentation, between 30:00 and 31:26 minutes, he received a bag with "a few table-spoons" of dust collected by Janette MacKinlay in January 2008. Janette MacKinlay is one of the four contributors of dust samples to Harrit e.al.. The dust had been collected from
(screenshot taken at 32:07)
One particular red/gray flake, designated “#13”, was photographed through a microscope (at 39:00),
and analysed using XEDS and then heated till ignition, and the burning recorded on video through a microspcope.
Here is the XEDS data, shown at 39:30 in the video:
This is how he describes the heating (40:17):
I am not showing the burn video sequence here. I don't think screenshots do it justice. It's at 41:42 - 41:59 in the video.
The XEDS graph resembles closely Fig. 7c in Harrit e.al., albeit with relatively less Fe or more Al and Si. While we have doubts about the precision of the Weight % listed in the table, we note that the weight proportion of Si : Al, 1.71% : 1.68%, translates to molar proportions of 98 : 100, in other words, according to Basile's calculation, there are only 2% fewer Si atoms in the red material than Al atoms.
We further note that about 73% carbon represents > 90% organic matrix. 2.63% Fe could represent 3.76% Fe2O3, binding 1.13% O. 1.71% Si could represent 7,86% aluminium silicate (kaolinite, Al2Si2O5(OH)4), binding 4.38% O. All other elements together are 1.8%.
If all the Al were elemental, and in a perfectly stoichiometric mix with Fe2O3 to form thermite, then 1.68% Al would require 3.48% Fe – Basile only found 2.63% Fe. Since Fe is 52.28% by weight of perfectly stoichiometric thermite, the red layer could at most contain 5.03% thermite. With ideal thermite having a theoretical maximum energy density of 3.9 kJ/g (see Harrit e.al., page 27), the red layer as a whole could at most inherit 5.03% of that, or about 196 J/g, from Fe-Al thermite. Most organic compounds have energy densities anywhere between 15 and 40 kJ/g. Assuming a reasonable average value of 20 kJ/g, and 90% organic matrix, the latter would add 18,000 J/g of energy density to the red material, or more than 90 times as much as the supposed thermite under the most ideal of circumstances.
http://www.youtube.com/watch?v=AJ7hXrmMRPc#!
According to the presentation, between 30:00 and 31:26 minutes, he received a bag with "a few table-spoons" of dust collected by Janette MacKinlay in January 2008. Janette MacKinlay is one of the four contributors of dust samples to Harrit e.al.. The dust had been collected from
"her fourth-floor apartment at 113 Cedar St./110 Liberty St. in New York City, across the street from the WTC plaza. As the South Tower collapsed, the flowing cloud of dust and debris caused windows of her apartment to break inward and dust filled her apartment. She escaped by quickly wrapping a wet towel around her head and exiting the building. The building was closed for entry for about a week. As soon as Ms. MacKinlay was allowed to re-enter her apartment, she did so and began cleaning up. There was a thick layer of dust on the floor. She collected some of it into a large sealable plastic bag for possible later use in an art piece" (Bentham paper, page 9).
Basile isolated various dust particles from the sample, using a magnet and a petri dish, among them “iron based microsperes, Red/gray chips, Red chips, Rust, Wire”, also “Silicate or glassy spheres”.
(screenshot taken at 32:07)
One particular red/gray flake, designated “#13”, was photographed through a microscope (at 39:00),
and analysed using XEDS and then heated till ignition, and the burning recorded on video through a microspcope.
Here is the XEDS data, shown at 39:30 in the video:
This is how he describes the heating (40:17):
I am not showing the burn video sequence here. I don't think screenshots do it justice. It's at 41:42 - 41:59 in the video.
The XEDS graph resembles closely Fig. 7c in Harrit e.al., albeit with relatively less Fe or more Al and Si. While we have doubts about the precision of the Weight % listed in the table, we note that the weight proportion of Si : Al, 1.71% : 1.68%, translates to molar proportions of 98 : 100, in other words, according to Basile's calculation, there are only 2% fewer Si atoms in the red material than Al atoms.
We further note that about 73% carbon represents > 90% organic matrix. 2.63% Fe could represent 3.76% Fe2O3, binding 1.13% O. 1.71% Si could represent 7,86% aluminium silicate (kaolinite, Al2Si2O5(OH)4), binding 4.38% O. All other elements together are 1.8%.
If all the Al were elemental, and in a perfectly stoichiometric mix with Fe2O3 to form thermite, then 1.68% Al would require 3.48% Fe – Basile only found 2.63% Fe. Since Fe is 52.28% by weight of perfectly stoichiometric thermite, the red layer could at most contain 5.03% thermite. With ideal thermite having a theoretical maximum energy density of 3.9 kJ/g (see Harrit e.al., page 27), the red layer as a whole could at most inherit 5.03% of that, or about 196 J/g, from Fe-Al thermite. Most organic compounds have energy densities anywhere between 15 and 40 kJ/g. Assuming a reasonable average value of 20 kJ/g, and 90% organic matrix, the latter would add 18,000 J/g of energy density to the red material, or more than 90 times as much as the supposed thermite under the most ideal of circumstances.
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