 | Curtis L. Hemenway, Peter MacKenzie Millman, Allan F. Cook - 1973 - عدد الصفحات: 404
...s"1, small compared to molecular velocities. The Reynolds number for equation (5) becomes R,= 10~3-6 s (cm), so that we are in the realm of Epstein's and...can be neglected. Hence, by equation (15), the time ti for a tiny grain to grow to a radius «i becomes <i = 6.3si(cm)yr (19) if we accept an accommodation... | |
 | Joy George - 1992 - عدد الصفحات: 394
...controlled leak valve [24]. The reactive gas pressure is maintained at 10-5- 10-4 torr, so that the mean free path of the gas molecules is of the order of centimeters (longer than the distance between the nozzle and the substrate). Some reactive gas atoms... | |
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cometesimals" of radius 100 m or larger at great solar distances. Correspondingly, the mean free path of the gas molecules is of the order of 1 m or more so that little error is made in applying Epstein's law up to perhaps s=10 m, while to about the same... 