PEP,

This is a very sharply peaked fiinction around f p with a width of the order of k T. (At T= is a step fiinction and its temperaPire derivative is a delta fiinction at p.) Thus in the integral for one can replace by its value at f p, transfomi the integration variable from to v and replace the lower limit of v, which is (-pEp), by (- ). Then one obtains... 

PEP theory has also been applied to modelling the free energy profiles of reactions in solution. An important example is the solvent effect on the SN2 reaction... 

Electrophoresis is used primarily to analyze mix tures of peptides and proteins rather than individual ammo acids but analogous principles apply Because they incorporate different numbers of ammo acids and because their side chains are different two pep tides will have slightly different acid-base properties and slightly different net charges at a particular pH Thus their mobilities m an electric field will be differ ent and electrophoresis can be used to separate them The medium used to separate peptides and proteins is typically a polyacrylamide gel leading to the term gel electrophoresis for this technique... 

Mernfield was awarded the 1984 Nobel Prize in chem istry for developing the solid phase method of pep tide synthesis... 

Critical micelle concentration (Section 19 5) Concentration above which substances such as salts of fatty acids aggre gate to form micelles in aqueous solution Crown ether (Section 16 4) A cyclic polyether that via lon-dipole attractive forces forms stable complexes with metal 10ns Such complexes along with their accompany mg anion are soluble in nonpolar solvents C terminus (Section 27 7) The amino acid at the end of a pep tide or protein chain that has its carboxyl group intact—that IS in which the carboxyl group is not part of a peptide bond Cumulated diene (Section 10 5) Diene of the type C=C=C in which a single carbon atom participates in double bonds with two others... 

N terminus (Section 27 7) The amino acid at the end of a pep tide or protein chain that has its a ammo group intact that IS the a ammo group is not part of a peptide bond... 

Fig. 19. Correction factor for axial dispersion as a function of NTU. SoHd lines are rigorous calculations broken lines, approximate formulas according to hterature (61). (a) Numbers on lines represent Pe values Pe = 20 /Lj = 0.8. (b) For design calculations. Numbers on lines represent Pep u ...

In the original study (61), NTU /NTU was calculated for thousands of hypothetical design cases as a function of both Pe and Pep -pu- The results were correlated and empirical expressions were given that can be evaluated on a handheld calculator, just as equations 76 and 77, but which approximate the computer calculation much better, to within about 5%. 

K. B. Bryan, PEP Review 90-3-1, SRI International, Menlo Park, Calif., 1991. 

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