Sweep volume

Isomerization needs some extra sweep volume. The volumes for the two mechanisms of azobenzene should be quite different—ca. 0.25 nm for rotation and ca. 0.12 nm for in version. This bears out in restricted spaces. In some zeolites azobenzene can isomerize whereas stilbene does not. Kuriyama and Oishi found that there are two separate AH versus AS lines for azobenzenes isomerizing by inversion (azobenzene type) and rotation (pseudo-stilbene type). ... 

Studied in this chapter. In particular, we adjusted an exponential decay to the first 10 seconds of the recovery at all 6 pressures, and we found a thermal isomerization rate for PMMA-DRl in the range 0.17 - 0.23 s, with no particular dependence on pressure. This result rules out pressure-induced static effects and reinforces the friction effects discussed it also shows that if trans has enough sweep volume to isomerize to cis, cis will also have enough sweep volume to isomerize back, a feature supported by the more compact and globular, i.e., twisted, conformation of the cis- versus the trans-DRl. 

Further to this, another experiment was carried out (Run 2). In this experiment, the feed volume was changed to 3 L (from 6 F in Run 1), sweep volume to 1 L (from 1.5 L), and the membrane area to 370 cm (from 415 cm ). It was observed that the sweep side concentration profile for these self-diffusion coefficient values matched reasonably well with the experimental findings [51]. The results are shown in Figure 34.22c. The self-diffusion coefficient of H" " ions has been investigated earlier... 

A third option is based on the relative sweep volume, which is the space through which an impeller pass per second is divided by the mixer volume. While this has been correlated to the specific energy consumed by the granulation (161), the dj was unable to be correlated. 

Jiible 2. Sweep Volumes tor the Isemeti/jiinn or Awknwnc and l-Aionaplhalcnc... 

Disk diameter is critical. A large-diameter disk imparts more energy as torque is a function of diameter. The larger diameter offers more circumference for liquid to be evacuated and carves out additional void volume in the material. The sweep volume of the disks is considered a major factor in properly scaling up a granulator (15). 

The Tg values of the polyimides were discussed on the basis of the sweep volume (conformational changes in rotation of around the biphenyl linkages). The sweep volume of the PI(i-BPDA) is the largest, and that of the PI(s-BPDA) is the smallest among the three kinds of Pis. The decrease in E at the Tg follows the order PI-(s-BPDA/4,4 -ODA) < PI-(a-BPDA/4,4 -ODA) < PI-(i-BPDA/4,4 -ODA), and this tendency is also interpreted in terns of the size of the sweep volume. The decrease in E at the Tg of polyimides from PDA was smaller (Figure 7.6). 

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