Cold flame

Thus, the maximum value of the Coriolis acceleration is at the cold flame boundary, which can be given as... 

The theory of the upper limit of hydrocarbons presents great interest. In mixtures of the higher hydrocarbons, for example, pentane, heptane and so on, with air the phenomena of the so-called cold flame occur, which is related to the formation of intermediate oxidation products here we do not consider this phenomenon, which has been studied in detail by Neumann and his associates at the Institute of Chemical Physics. The simplest hydrocarbon, methane, does not yield these phenomena, and either burns at a relatively high temperature, or does not bum at all. 

Fig. 3. Self-ignition of polypropylene (PP) in oxygen 1) slow oxidation, 2) cold flame, 3) mnltiplet secondary cold flames, 4) two-stage seif-ignition. The single-stage self-ignition is not shown (After Ref. with permission)...

The products of the oxidation of carbon disulfide include SO2, S2O, CO2, CO, OCS, and sulfur. SO and CS intermediates have been observed in the cold flame " Kondratiev reported the yields of SO2, CO, OCS, and S2 as functions of the initial [O2] [CS2] ratio in flames. At a ratio of 2.5 1, the products were almost exclusively SO2 and CO in a ratio of 2 1, suggesting that the bulk of the reactants obeyed the stoichiometry... 

Atomic spectrometric tests the air/acetylene flame is not recommended for these, as several metals interfere in this relatively cold flame. 

Under appropriate experimental conditions a "cold flame" could be produced by this reaction in water. 

Rosenfeld and Sugden also analysed the chemiluminescence from lead at 406 nm in a series of very cold flames at atmospheric pressure. They succeeded in obtaining individual values for the coefficients averaged over the temperature range 1350-1450 K (cm molecule" s" ) ... 

Frank-Kamenetskii (1947) has given a chemical interpretation to the Lotka-Volterra model he has shown that oscillations in the cold flame can be described using the model. 

Cold flame reaction, which is characterized by luminescence and a small change in temperature. 

Non-catalytic system (cold-flame combustion) or catalytic system (Sn02)... 

The validity of the law (7.1) for the lower combustion gas limit has been repeatedly proved, with very rare exceptions. On the contrary, the upper limit of flame propagation meets the conditions (7.1) is an exception for most of the cases. There are many reasons for this cold flame of one of the components, selective diffusion etc. Combustion of H2 + CO, H2 + CH4, H2 + C3H8, and H2 + C2H4 mixtures with air complies satisfactorily with Le Chatelier s law [51]. 

Figure 12.7 Illustration of the temperature and pressure conditions necessary to obtain a cold flame.

However, the surface area of samples issued fnxn the flame reactor greatly decreases as a result of the standard treatment. The larger the initial surface area, the more important its decrease (Table 1, columns 5 and 6). This is particularly obvious for the M0O3-A sample prepared in a cold flame since its surface area is reduced more than fourfold. 

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