Torsion secondary effects

The length of the sample kept between the clamps differs from the effective value, for fundamentally two reasons. On the one hand, the section in which the torsion is zero lies within the zone covered by the clamps, so that the clamp separation is smaller than the effective sample length. On the other hand, as stated earlier, the secondary effects of the torsion produce an... 

The secondary dispersions, at -10 and —85 , presumably can be attributed to side group rearrangements as are the P mechanisms and other secondary effects discussed in Chapter 15. But it is difficult to guess the relative roles of volume and shear deformations in these motions. In shear (torsion) measurements at about 10 Hz, Schmieder and Wolf found secondary maxima in tan 6 at —30 and -100°C. No certain identification of these respective mechanisms can be made, since maxima in a and tan 6 are not really equivalent, and the respective frequency ranges are very different. If the secondary maxima in Fig. 18-17 do correspond to the secondary shear maxima, the temperature dependence of the associated relaxation times must be quite high. 

Keywords it-Facial selectivity, a/ir Interaction, CH/ir Interaction, Ciplak effect, Diels-AIder reaction, Electrostatic interaction, Orbital mixing rule. Orbital phase environment, Secondary orbital interaction, Steric repulsion, Torsional control... 

The torsion angles around the bonds of the sugar-phosphate DNA backbone are of decisive importance for the secondary structure of DNA as well as for base-base recognition. [44] For antisense agents to be effective inhibitors of protein expression in vivo, they have to resist the action of DNA-degrading enzymes and bind to their... 

Additionally, secondary structure mimetics can be used to introduce constraints that may either have local or global effects. The secondary structure of a peptide is dominated by energetically favoured torsion angels ( ), cp and co, together with... 

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