Soot comparison

Fullerenes are described in detail in Chapter 2 and therefore only a brief outline of their structure is presented here to provide a comparison with the other forms of carbon. The C o molecule, Buckminsterfullerene, was discovered in the mass spectrum of laser-ablated graphite in 1985 [37] and crystals of C o were fust isolated from soot formed from graphite arc electrodes in 1990 [38]. Although these events are relatively recent, the C o molecule has become one of the most widely-recognised molecular structures in science and in 1996 the codiscoverers Curl, Kroto and Smalley were awarded the Nobel prize for chemistry. Part of the appeal of this molecule lies in its beautiful icosahedral symmetry - a truncated icosahedron, or a molecular soccer ball, Fig. 4A. 

Fig. 11. The loss of carbon rapidly increases with the increase of temperature. Heating of the catalysts in open air for 30 minutes at 973 K leads to the total elimination of carbon from the surface. The gasification of amorphous carbon proceeds more rapidly than that of filaments. The tubules obtained after oxidation of carbon-deposited catalysts during 30 minutes at 873 K are almost free from amorphous carbon. The process of gasification of nanotubules on the surface of the catalyst is easier in comparison with the oxidation of nanotubes containing soot obtained by the arc-discharge method[28, 29]. This can be easily explained, in agreement with Ref [30], by the surface activation of oxygen of the gaseous phase on Co-Si02 catalyst.

Diffraction of detonation from a tube (0=52 mm) to half-space through an annular orifice with central conical obstacle ( = 15°) in a C2H2 + 2.5O2 mixture at 33 mbar initial pressure. Comparison of experimental soot patterns with numerical simulations. (Courtesy of B. A. Khasainov.)... 

Comparison of Toxicity of Diesel Soot and Carbon Black... 

Fig. 6 Comparison of soot yield for various hexanes. Adapted from ref. 40.

Figure 6.3 Comparison of uncontrolled and controlled soot emissions for different fuel forcing levels between propane (1 — minimum and 2 — maximum soot level) and ethylene (3 — minimum and 4 — maximum soot level)...

The combustion efficiency of the benzene was beyond 99.999% even at an overall equivalence ratio of 1.0 (including the entrainment air which was 30% of the total air flow). With the controller off, the flame was extremely sooty and, in fact, sooting as the quartz tube would be blackened and the mass spectrometer sampling probe clogged in a matter of seconds, and soot was sucked into the scrubber system. This comparison between controller off and controller on conditions with benzene fuel is extremely dramatic and shows the efficacy of active combustion control in vortices to eliminating soot from diffusion flames. 

Figure 9.55a shows the results of single-particle analysis (see Chapter ll.B.4a) of a typical particle in the upper troposphere (Murphy et al., 1998). In the negative ion spectra, a variety of fragments due to organics are observed, along with sulfates and some halogens. In other particles, soot and minerals were also common constituents. For comparison, Fig. 9.55b shows that a typical particle in the stratosphere is primarily sulfate (see Chapter 12.C.5). 

Fig. 40. Comparison of flow distribution at the entrance of a DPF with different radially non-uniform soot distributions computed by CFD and a simple network model.

The lees of wine dried and similarly charred and ground with glue yield an excellent black and the better the wine from which it comes, the better the imitation, not only of the ordinary black, but even of indicum. By indicum in this connection Vitruvius doubtless refers to India ink or China ink, for Pliny also, in describing black pigments, after mentioning soot and lampblack and charcoals as above, says after Vitruvius that the black from wine lees, if the wine is of good quality, will bear comparison with that of indicum. He further states that indicum is a substance imported from India and that the composition of it is unknown to him.89... 

Fig. 22, Comparison of current voltage curves of cathodic oxygen reduction in alkaline electrolyte (a) PTFE-bonded nonactived soot cathode, (b) PTFE-bonded Pt-activated soot cathode, (c) Silflon cathodes consisting essentially of submicrometer PTFE particles covered by a 0.1-fim Ag layer.

Fig. 26. Comparison of current voltage curves of membrane fuel cells using impregnated PTFE-bonded eleclrodes (a) prepared from soot activated by 20 wt% Pt and (b) with additional Pt sputtering of ihe contacting surface.

Klippel N, Nussbaumer T (2007) Health relevance of particles from wood combustion in comparison to Diesel soot. In 15th European biomass conference, Berlin 7-11 May 2007... 

Boogaard H, Montagne DR, Brandenburg AP, Meliefste K, Hoek G (2010) Comparison of short-term exposure to particle number, PM10 and soot concentrations on three (sub) urban locations. Sci Total Environ 408 4403 1411... 

In the interstellar medium less stable PAHs will be weeded out, leaving a mixture dominated by the most stable structures [17, 19]. These more stable PAHs are those which are symmetric and generally in the most condensed forms. An example of a mixture comprised largely of the most stable molecular forms is the soot formed in the high temperature combustion of hydrocarbons. A comparison of the Raman spectrum in the 1800 to 1000 cm-1 region of auto soot with the interstellar IR emission spectrum from Orion is shown in Fig. 7. The Raman spectrum of soot... 

Fig. 7. Comparison of the 5 to 10 micron Raman spectrum of auto soot (a form of amorphous carbon which is rich in the more stable PAHs) with the emission from Orion (soot spectrum, adapted from Ref. [62], Orion from Ref [47]) (Figure from Ref [12])...

Figure 1. Qualitative comparison of a free swelling experiment on a soot-coloured hydrogel disc (experiment by J. M. Huyghe, 1999) with the 3-d FEM simulation via PANDAS...

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