Bands of regularity

The need for an account of inertial effects in relaxation at hi frequencies has been known for a considerable time. - In dilute gases a description in terms of free rotation perturbed by collision is substantially developed to account for the shapes of i.r. and Raman lines. In crystals at sufficiently low temperature, description in terms of bands of regular oscillations perturbed by anharmonicity provides a regular sequence of approximations. In dense gases and in liquids - it is necessary to face simultaneously a complex pattern of molecular motions and a difficult question of the delayed electrical interaction which gives rise to the internal... 

A consequence of tacticity/stereoregularity is the production of regular helical coiling of the polymer chain. Helical coiling is a secondary structure for synthetic polymers associated with the primary structure of the tactic sequence. Using IR spectroscopy, it has been possible to assign some unique bands to... 

Table 2.4 summarizes the above in terms of a shopping list for new items. It is once again emphasized that the numbers are to be understood as indicative (e.g., not for use in grant proposals). And recall that old spectrometers are not necessarily inferior at all to new ones, and they can be very cheap if standing in someone s way. Also, items such as frequency counters up to X-band appear regularly as second hand offers on the Internet for a fraction of their new price. And finally, the table does not show possible hidden costs, that is, of items that are taken for granted because they already happen to be around, but whose budgeting may be prohibitive when they have to be acquired, for example, square meters of lab space or dedicated operators. 

Rock salt bed.-—-An immense basal bed of alteres Steinsalz—older rock salt—broken up at fairly regular intervals with two- to five-inch bands of anhydrite, CaS04. 

When illuminated by an incandescent gas lamp, tellurium vapour exhibits an intense bluish-green fluorescence. Under the light of a mercury vapour lamp the fluorescence is much less intense. The fluorescence spectrum consists of regularly spaced bands in the visible region.12... 

As shown in Figure 2, the infrared vibration bands of sample A (1236, 1090, 965, 800, 564 and 465 cm-1) are close to those of sample B (1234, 1090, 964, 799, 568 and 465 cm-1). They show that the internal local structures of both hexagonal silica frameworks are almost identical. With the transformation of regular hexagonal structure into amorphous phase (amorphous-1), all of network vibration bands are shifted to... 

Figure 10. Proton NMR spectra of the ALPH3 band of 0.1 vol% APS in regular water. A large hump which is prominent in the stale solution is believed to result from oligomerization because of poor preparation techniques. See text for further discussion.

DF image. This observation, again, is comparable to what has been seen in PPT fibers (5J. In the thinner part of the fragment the banding is regular, and each transverse dark band, 200 A in width, makes an angle of about 70° with the fiber direction. The periodicity of the banding is of about 1200 A, as compared to... 

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