Chain fragment, symbol

Fig. 63. Oxygen concentration dependence of the fraction of paramagnetic chain fragments as calculated from the integrated intensities of the ESR signals in YBajCujO j (solid symbols, right scale). The oxygen concentration dependence of the sc phase-transition temperatures is also shown (solid line, left scale). The inset shows the concentration dependence of the paramagnetically active chain fragments for two different sample preparation temperatures as calculated using a modified lattice gas model. From Sichelschmidt...

The polymeric chain is symbolically cut into a number of fragments called model molecules or model compounds. To best reproduce the polymer, one model molecule must have a number of atoms overlapping a similar grouping in the following fragment. 

Fig. 12. Tentative model of the signal transduction chain that links the perception of pectic fragments to defense responses in carrot cells. Abbreviations apy, heterotrimeric G protein CaM, calmodulin 4CL, 4-coumarate-CoA ligase CTX, cholera toxin FC, fusicoccine GDP-P-S and GTP-y-S, guanosine 5 -0-(2-thiodiphosphate) and guanosine 5 -0-(3-thiotriphosphate) IP3, 1,4,5-inositol trisphosphate PAL, phenylalanine ammonia-lyase PLC, phospholipase C PR, pathogenesis related PTX, pertussis toxin Rc, receptor SP, staurosporine. Activation and inhibition are symbolized by + and -respectively.

The last type of these fragments results from the complete loss of the side chain and is symbolized as v . This fragment containing the C-terminal moiety is intense for amino acids that do not easily yield w type fragments. No equivalent containing the N-terminal moiety has ever been observed. 

When the designation of a symbol is clear, the lowercase letters may be dropped, e.g., C42. Peptide chains are designated by Greek letters, and, if altered by a cleavage reduction, a prime is added, e.g., a. Fragments of peptide chains are designated with numerals, e.g., a -l, a -2. 

Relative concentrations of relevant species as a function of time determined via In s/tu H-NMR spectroscopy during the CDB-mediated polymerization of styrene at 70 °C, where C = cumyl fragment, S = styrene, D = dithiobenzoate. The non-assigned symbols are CiP-lnItiated chains as indicated In the ClPDB study (see Figure 1). [STY] [CDB] [AIBN] = 6.7 i o,2 [mol]. ... 

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