Pyrolysis during

The external heat flux (q"x) from the cone heater does not exclusively determine the heat flux important for samples pyrolysis in the cone calorimeter, since the reradiation from the hot sample surface (q"eTad), the loss by thermal conductivity into the specimen and the surroundings ( I SS), and the heat flux from the flame (q Lmt) are also of the same order of magnitude.82 85 Thus, the heat flux effective with respect to pyrolysis during a cone calorimeter run (qeii) is the result of the external heat flux and the material s response (qeB = q L + < L - gCad - qLs). 

The formation of copper(I) fluoride in reaction (45) seems unlikely, but low yields of aryl copper compounds are obtained owing to pyrolysis during preparation. 

Isothermal pyrolysis A pyrolysis during which the temperature is essentially constant. 

The pyrolytic carbon deposition is low at low temperatures (200 and 250 °C), then increases to reach a maximum around 350 °C and decreases at higher temperatures. The low values noticed at low temperatures correspond to a phase of pyrolysis during which the volatilization of the solid matrix is just beginning. The recombination of atoms of carbon with the carbonized structure is thus strongly reduced. 

Benzene is a major component in PVC pyrolysis. Other aromatic components also are present- In addition to the compounds indicated in Table 6.3.2, heavier aromatic compounds such as naphthacene and benzo[b]phenanthrene were indicated in PVC pyrolysates [23], Also, a more complete list of aromatic compounds generated in pyrolysis during non-flaming burning of PVC is reported in literature [24], Compounds with two, three, four aromatic cycles and even benzo[ghi]perylene (six cycles) are included in this list. 

The main difference between gasoline and diesel fuel, as far as ETAAS are concerned, is the sample volatility. Gasoline sample can be injected directly in the electrothermal atomizer and vaporized without formation of any residue, while diesel fuel undergoes partial pyrolysis during the thermal treatment before the atomization occurs. The pyrolysis can lead to the formation of a carbonaceous residue. The carbonaceous buildup affects the atomization of carbide forming elements such as Ni and V [3]. In this work, diesel fuel samples were diluted with a suitable solvent to reduce the formation of carbon residues. 

This holds true, in particular, for the stage of pyrolysis, during which oxygen contaminations of up to 10% may occur. Since oxygen impurities exceeding 1 wt% significantly affect the performance of the ceramic product this issue is of crucial importance. 

One of the earliest publications on the preparation of carbon molecular sieves was done by Walker et al. [6]. They started from a Saran copolymer, but currently many different raw materials are being used either for research or commercial purposes. The main sources of carbon molecular sieves for commercial applications are coal and coconut shell. An extensive list of the work done in the preparation of carbon molecular sieves can be found elsewhere [7,8]. The typical steps in the preparation of carbon molecular sieves from coal are shown in Fig. 1 [8]. It can be seen that the main steps are oxidation, carbonization, followed either by steam activation or pyrolysis. During steam activation, pores are opened and the resulting carbon molecular sieve can be used in hydrogen purification, while during pyrolysis carbon deposition takes place, and a narrower pore size distribution is achieved. 

The discrepancy between our results and the previous results appears to be due, at least, in part, to different ways of heating the samples. Hillman and coworkers claimed that the ESR parameters of the samples were insensitive to the details of the heating process. The results that they reported came, in fact, from samples that were heated in ESR tubes. The samples were, thus, in contact with the gaseous products of pyrolysis during the heating. These shielded the samples from the atmosphere. In addition, it is known that the course of charring is different if the sample is kept in contact with pyrolysis products (11). 

BEFORE HYDROUS PYROLYSIS DURING HYDROUS PYROLYSIS AFTER HYDROUS PYROLYSIS... 

Let us see the example of the reduction of uianyl fluoride by pyrolysis during which the uiaityl fluoride is heated in the presence of both water and hydrogen... 

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