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Arrhenius relationship, component

The dynamic model involves a component mass balance, an energy balance, the kinetics and the Arrhenius relationship. Hence... [Pg.340]

A sequence of wafers was polished for a duration adequate to ensure the attainment of thermal stability. The final or equilibrium temperature could then be plotted against the equilibrium removal rate. In the spirit of treating CMP like a chemical reaction, we can plot log of equilibrium removal rate vs. inverse absolute equilibrium (instantaneous) temperature. We have done so for the standard, two-component slurry, the abrasive alone and the oxidizer alone, in Fig. 2, below. Note that each of the three sequences results in a straight line when plotted in this manner, and that moreover, the slopes of the three lines are very similar. The implication of the straight line fits (except near room temperature for the standard slurry) and the similar slopes is that the polish rate obeys an Arrhenius relationship, and that the activation energy is similar for the slurry and each of its components, differing only in the fi"equency factor constant. Further, that while the rate for a given slurry proceeds like a chemical reaction, efficacious removal is achieved only with a combination of oxidizer and abrasive. [Pg.157]

The first decay component (ti) contributes to the short time regime (it is over in a hour). The second component accounts for the thermal relaxation of the polymeric matrix and the parameter t2 shows a well defined dependence on temperature. The following Arrhenius relationship between the decay probability l/t2 and the inverse temperature 1/T can be assumed ... [Pg.137]

The consequences of long heat-up and cool-down times in batch sterilization can be severe if the medium components are heat-sensitive. This arises because the destruction due to heat is dependent on the value of the thermal death constant. It can be shown that the spore B. stearothermophilus is only significantly inactivated above 110°C due to its high activation energy of 67.7 kcal/mol. On the other hand, many organic nutrients which also follow Arrhenius relationship for thermal degradation, have a much... [Pg.483]

The examination of fold endurance and tensile strength of a series of polymer-paper systems under thermal accelerated aging indicates that only in the most favorable of circumstances is it possible to apply the Arrhenius equation to the system. It also seems unlikely that a sample addition relationship exists between the behavior of the individual components and their behavior as a system. A straight line plot of log folding endurance vs. aging time may reflect a fortuitous composite of several experimental variables leading to pseudo-first-order deterioration. [Pg.350]

Complete characterization of the kinetic parameters for the HKR of epichlorohy-drin was then obtained by evaluation of the reaction dependence on temperature. A standard experiment at 25 °C (Fig. 19) was numerically fitted, which allowed the expression of the kinetic constants in term of an Arrhenius law relationship (Eq. 21). From this relationship, the activation energy (E ) and pre-exponential frequency parameter (ki) were derived for each component of the reaction (Tab. 8). Of significant practical importance is the impact an increase in reaction temperature has by decreasing the selectivity of the HKR and increasing the level of impurity production. For this experiment, a maximum yield of only 44% (to reach ee>99%) was possible compared with 48% when the reaction was performed at... [Pg.187]


See other pages where Arrhenius relationship, component is mentioned: [Pg.17]    [Pg.350]    [Pg.124]    [Pg.319]    [Pg.87]    [Pg.2517]    [Pg.61]    [Pg.202]    [Pg.60]    [Pg.921]    [Pg.443]    [Pg.121]    [Pg.333]    [Pg.1056]    [Pg.177]    [Pg.23]    [Pg.439]    [Pg.328]   


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Arrhenius relationship

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