Power feed system, linear

The MW dependences of the normalized chain relaxation times in melts of linear and branched samples are compared in Fig. 12. Both can be represented by scaling power laws, but with remarkably different scaling exponents. For the melts of linear chains, the exponent 3.39 is observed close to the typical value of 3.4 for such systems. In contrast, for the fractions of the branched polymer, the exponent is considerably lower (2.61). It is interesting to note that the value of the normalized chain relaxation time for the feed polymer with the broad M WD fits nicely into the data for the fractions with narrow MWDs. This seems to indicate that conclusions can also be drawn from a series of hyperbranched polymers with broad MWDs. 

As the power input is increased (at a given flow rate), the domain of plasma polymerization approaches the monomer-deficient one, which can be recognized by the asymptotical approach of D.R. value to a horizontal line as the power input increases. In the monomer-deficient domain, the deposition rate (plateau value) increases as the flow rate is increased and shows a linear dependence on the monomer feed-in rate at a given discharge power and the system pressure (Fig. 8.2), i.e.,... 

The C,5 C g linear paraffins are adsorbed more strongly than ammonia so to achieve desorption a very high ammonia flow rate (about four times the hydrocarbon feed rate) is required. The desorption cycle is therefore operated under downflow conditions. Pressure drop across the bed is relatively high, necessitating the use of a relatively shallow bed and an oversquare configuration but, even so, the power costs associated with the ammonia circulation system make a significant contribution to overall process costs. 

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