Fair alignment

When a linear speed of the rotating drum surface, which serves as a fiber take-up device, matches that of evaporated jet depositions, the fibers are taken up on the surface of the drum tightly in a circumferential manner, resulting in a fair alignment. Such a speed can be called as an alignment... 

Low sensitivity to lateral decenters (hence to gravity, wind and thermal excitations), the alignment of the primary and secondary mirrors being quite inconsequential, and stiffness at the location of the critical subsystem (the corrector) being fairly high ... 

Later on we succeeded in partially aligning microcrystals within the sample they were placed in X-ray capillaries and pulled down by gently sucking their mother liquor, whereupon the needle-shaped crystals oriented along the capillary axis. Such samples sometimes, but only under perfect measuring conditions, produced pseudo fiber patterns which consisted of oriented arcs with average length of 60° (Fig. lb). In many cases these arcs were comj sed of distinct spots that could be clearly resolved by eye. Since such patterns may arise from partial orientation of the nucleic acid component within fairly well packed particles, these patterns indicated reasonable internal order. 

Through the use of multiple experimental techniques, we have shown how both the NXL and XL phases of PILE interact and respond to applied tensile deformation. Strains transmitted to PILE crystals lead to two distinct slip modes and, at higher strains, to the breakup and alignment of lamellar fragments. In our experiments, crystallites in PTFE orient fuUy with respect to the draw direction at strains between 70 to 200%. With increasing strain, some chains originally in the XL phase are transformed to NXL material. Noncrystalline chains continue to orient until macroscopic failure is reached. This could be a fairly general microstructural response for semicrystalline polymers. 

Such increases of y- and -relaxation temperatures with increasing draw ratio are thought to be due to the limited mobility of molecular chains in the noncrystalline region. As pointed out in the foregoing section, the amorphous molecular chains align fairly well parallel to the drawing direction. Therefore, the conformational versatility and mobility of such molecular chains are considered to be much restricted. 

The lower effective concentrations found in intramolecular base catalysis are due to the loose transition states of these reactions. In nucleophilic reactions, the nucleophile and the electrophile are fairly rigidly aligned so that there is a large entropy loss. In general-base or -acid catalysis, there is considerable spatial freedom in the transition state. The position of the catalyst is not as closely defined as in nucleophilic catalysis. There is consequently a smaller loss in entropy in general-base catalysis, so that the intramolecular reactions are not favored as much as their nucleophilic counterparts. 

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