Carbon soot

Direct-Flame Incinerators. In direct-flame incineration, the waste gases are heated in a fuel-fired refractory-lined chamber to the autoignition temperature where oxidation occurs with or without a visible flame. A fuel flame aids mixing and ignition. Excess oxygen is required, because incomplete oxidation produces aldehydes, organic acids, carbon monoxide, carbon soot, and other undesirable materials. 

Carbon soot from resistive heating of a carbon rod in a partial helium atmosphere (0.3bar) under specified conditions is extracted with boiling C H or toluene, filtered and the red-brown soln evapd to give crystalline material in 14% yield which is mainly a mixture of fullerenes C q and C70. Chromatographic filtration of the crude mixture with allows no separation of components, but some separation was observed on silica gel... 

Onion-like graphitic clusters have also been generated by other methods (a) shock-wave treatment of carbon soot [16] (b) carbon deposits generated in a plasma torch[17], (c) laser melting of carbon within a high-pressure cell (50-300 kbar)[l8]. For these three cases, the reported graphitic particles display a spheroidal shape. 

Several studies have shown that the direct electron transfer between cat and graphite or carbon soot electrodes in deoxygenated solutions was sluggish, with large peak separations [157-159], Based on the consideration that CNTs might be the best candidate among the various carbonaceous substrates for promoting the electron transfer... 

Tsuchiya T, Wakahara T, Lian Y, Maeda Y, Akasaka T, Kato T, Mizorogi N, Nagase S (2006) Selective extraction and purification of endohedral metallofullerene from carbon soot. J. Phys. Chem. B 110 22517-22520. 

Figure 5.15 shows the pattern made by the normal reflection of a detonation on a glass plate coated lightly with carbon soot, which may be from either... 

Kareev IE, Bubnov VP, Fedutin DN (2009) Electric-arc high-capacity reactor for the synthesis of carbon soot with a high content of endohedral metallofullerenes. Tech Phys 54 1695-1698... 

Novakov, T. "Role of Carbon Soot In Sulfate Formation", presented at the ACS/CSJ Chemical Congress, Honolulu,... 

Carbon - The aerosol collected on the Tissuequartz filters was analyzed for total carbon by the nondestructive technique of proton-induced gamma-ray emissions (17) and graphitic carbon (soot) by calibrated optical reflectance at Washington University, St. Louis, Missouri. The estimated error in measurement of total carbon per filter was 5 yg or 20%, whichever was greater. The estimated error for soot was lyg or 20%, whichever was greater. 

Particulate carbon in the atmosphere exists predominantly in three forms elemental carbon (soot) with attached hydrocarbons organic compounds and carbonates. Carbonaceous urban fine particles are composed mainly of elemental and organic carbon. These particles can be emitted into the air directly in the particulate state or condense rapidly after Introduction into the atmosphere from an emission source (primary aerosol). Alternatively, they can be formed in the atmosphere by chemical reactions involving gaseous pollutant precursors (secondary aerosol). The rates of formation of secondary carbonaceous aerosol and the details of the formation mechanisms are not well understood. However, an even more fundamental controversy exists regarding... 

Choi, W., and M.-T. Leu, Nitric Acid Uptake and Decomposition on Black Carbon (Soot) Surfaces Its Implications for the Upper Troposphere and Lower Stratosphere, J. Phys. Chem. A, 102, 7618-7630 (1998). 

Britton, L. G., and A. G. Clarke, Heterogeneous Reactions of Sulfur Dioxide and S02/N02 Mixtures with a Carbon Soot Aerosol, Atmos. Environ, 14, 829-839 (1980). 

Novakov, T., S. G. Chang, and A. B. Harker, Sulfates as Pollution Particles Catalytic Formation on Carbon (Soot) Particles, Science, 186, 259-261 (1974). 

Blake, D. F., and K. Kato, Latitudinal Distribution of Black Carbon Soot in the Upper Troposphere and Lower Stratosphere, J. Geophys. Res., 100, 7195-7202 (1995). 

The sensitivity of AN to heat is always increased by the presence of.organic compounds, provided that the proportions of these do not exceed certain limits. Among the substances investigated are cellulose, paper, pulverized carbon, soot, sawdust, waxes, paraffin, TNT, NS, DNT and drip oil. For instance, the presence of 5% NS in AN increased the sensitivity to such an extent that the mixture detond when heated to about 150°. The presence of paper bags such as the containers for FGAN was a contributing factor to the Texas City disaster in 1947. 

Carbon black [1333-86-4 and soot are formed either by pyrolysis or by partial combustion of vapors containing carbon. Soot as an unwanted byproduct of combustion (e.g., in chimneys or diesel engines) is a poorly defined material. Besides carbon black particles, it often contains significant amounts of ash and high amounts of polycyclic aromatic hydrocarbons (PAH) [4.1]. Residual hydrocarbons, which can be determined by extraction with solvents (e.g., toluene), can account for 30 wt%. 

In 1984. scientists (Rohlling. Cox. and Caldor at Exxon Research and Engineering) created clusters of carbon (soot) by the laser vaporization of a carbon target rod in connection with a supersonic nozzle. By means of mass spectroscopy, the researchers determined the relative abundance of the carbon clusters produced. Small, 20- to 40-atom clusters of carbon were expected inasmuch as these had been produced a number of times by earlier investigators working on the soot problem. In such experiments, an interesting but unexplained question always arose—Why were only even-numbered carbon clusters produced in the complete absence of odd-numbered clusters See Fig. 3. 

The results obtained form source apportionment provide valuable information to set up cost-effective and efficient mitigation options which are especially of relevance for agglomeration areas. Most prominently, low emission zones have been introduced in many cities and conurbations. The effectiveness of this measure has been proven by significant decrease of black carbon (soot) concentrations however, it does not affect non-exhaust traffic emissions, thus being less impressing when looking at its effect on PM10 levels [80],... 

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