Persistence length Subject

The value and ionic strength dependence of the persistence length a have been the subject of sharp controversy (for review see [85F2]) which by now is settled and only the most reliable data are presented here. All data correspond to neutral pH and room temperature. The standard conditions correspond to about 0.2 M sodium (in most cases NaCl). 

The electrostatic effect of an ionic substituent on the reactivity of a functional group subject to attack by another ion persists over a much greater length of intervening chain than is found for the influence of an unionized substituent (compare column B of Table V). This follows of course from Coulomb s law. From the standpoint of polymer reactions, it is important to bear in mind that when charged... 

Since we did not find adverse effects on zinc balance by the higher fiber diet containing spinach until the fourth week of study 3, balance studies should be carried out for longer periods of time to determine if negative zinc balances persist. Perhaps in the earlier studies on effects of spinach on calcium balance of human subjects, more definitive effects would have been noted if the spinach had been fed along with a higher fiber diet. Length of study period is also a likely factor, as some of the studies were carried out for less than 2 weeks. 

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