Growth rate vs. temperature

The rate coefficients of reactions (15)-(27) were taken from the results of ab initio calculations. Reactions (28) and (29) describe the process of surface dehydroxylation/hydroxylation. We used a value of 1013 sec-1 as an estimation of the preexponential factor (this value corresponds to the characteristic frequency of internal vibrations of the reaction center) for the desorption reaction. To describe the experimental dependence of the growth rate vs. temperature adequately, we considered that the water adsorption energy is a linear function of the hydroxylation degree / ... 

Explain the relative effect of growth rate vs. temperature for surface-reaction and mass-transport Idnetically crmtrolled thin film MOCVD processes. Why does the growth rate decrease for depositions taking place at very high temperatures ... 

Figure 6.10 Schematic of growth rate vs. temperature difference from its melting temperature.

In contrast, based on respiration measurements, giant sequoia is predicted to grow efficiently, albeit slowly, near 0 "C, increase rate and efficiency up to about 15 "C, decline in growth rate with higher temperatures, and stop growth above 21 "C. The growth rate vs. temperature patterns predicted from calorespirometry measurements indicate the distinct temperature responses of the two redwoods that are evident in their native growth environments. 

Finally, we were led to the last stage of research where we treated the crystallization from the melt in multiple chain systems [22-24]. In most cases, we considered relatively short chains made of 100 beads they were designed to be mobile and slightly stiff to accelerate crystallization. We could then observe the steady-state growth of chain-folded lamellae, and we discussed the growth rate vs. crystallization temperature. We also examined the molecular trajectories at the growth front. In addition, we also studied the spontaneous formation of fiber structures from an oriented amorphous state [25]. In this chapter of the book, we review our researches, which have been performed over the last seven years. We want to emphasize the potential power of the molecular simulation in the studies of polymer crystallization. 

Fig. 26 Growth of each lamella, the number of atoms in the lamella, vs. time, a at 330 K and b at 350 K. Please notice that the lamellae show quite different growth rates especially at higher temperatures...

Fig. 11 Crystal growth rate Gt vs. temperature for a 75 25 w/w mixture of C162H326 and C98H198. The poisoning minimum at the melting point of C98H198 (116 °C) is seen. The steep increase in G below 112.5 °C (out of scale) is due to the transition to once-folded C162H326 growth (from [31])...

Fig. 22 Ratio of growth rates Gioo/Gno vs. crystallization temperature for extended-chain crystals of Ciggfbgg from 2% (w/v) solution in octacosane (diamonds) and for linear polyethylene from 0.05% solutions in hexane (squares). The polyethylene crystal at Tc = 70.0 °C and the C198H398 crystals above Tc = 110 °C are non-truncated lozenges these form for any Guo/ cos( /2) > G100, where cp/2 = tan 1(flo/ o) and ao, b0 are unit cell parameters (cf Fig. 10). Data for PE are from [32] (from [45])...

Droplet growth rates and viscosity decline rates both are exponential processes, following a straight line on a semi-log plot (log x or log vs. time), where is the mean droplet diameter. Emulsion failure is also associated with a certain minimum viscosity, depending on water content, crude-oil content, temperature, etc. Viscosity and mean droplet size may be projected to estimate the time remaining before emulsion failure. The ultimate droplet size and viscosity should be determined experimentally for the same formulation in a pilot-plant pipe loop. 

Growth Rate and Bulk Resistivity vs. Deposition Temperature... 

Figure 34. Initial crystal growth rate (Gt, along [010]) vs crystallization temperature from 1.1 wt % ( . ) and 4.2 wt % solutions (A, a) of CigsThgs in 1-phenyldecane. ( , a) extended chain, ( , a) once-folded chain crystals. 7 and 7 are the dissolution temperatures of extended-chain and once-folded-chain crystals. The retardation in growth around 7dF is caused by self-poisoning (from ref 192 by permission of American Physical Society).

Fig. 4.29 (a) Lamellar growth rates for PEO as function of crystallization temperature Tc (inset lamellar dimensions vs. crystallization time) and (b) lamellar thickness plotted against inverse undercooling. The linear fit of the lamellar thickness vs. inverse undercooling plot with the boundary condition (0,0) yields a satisfactory result. Adapted with permission from [52]. Copyright 2002. American Chemical Society... 

For solvent systems with a window of operating temperature, proper selection of the method of supersaturation generation (e.g., cooling and antisolvent addition) and mode of crystallization (e.g., batch vs. semicontinuous) can also affect the overall crystal growth rate. In many instances in which solvent or impurity rejection becomes critical, adequate mixing to avoid local high supersaturation can be critical. Examples 9-2 and 10-4 illustrate two cases of rejection of impurities and residual solvent. These examples show how various means are applied to overcome these complications. 

Figure 1. Schematic plot of impingement rate vs. reciprocal absolute temperature showing conditions for film growth in conventional physical vapor deposition.

Figure 2.76 Growth rate of bacterial biomass vs. temperature (Madigan et a/., 2003 Lu,...

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