Mean values, structural analysis

The Car values for the three macerals can be obtained by x-ray structural analysis (5). From the mean lamellae diameter N values can be calculated which principally measure the mean number of atoms in a hexagonal network and in the same plane. Therefore, N can represent either only the Car atoms of the cluster or the Car atoms and also atoms like C.i, O, N, and S which are directly linked to the aromatic cluster. In the first case, N=C r ,i,x) and in the second case N=C ,r + X, X being the number of substitution places (C .r(>nliM) ) except direct bonds. 

The results of a two-dimensional X-ray analysis of the 12-molecule crystal structure (McIntosh et al., 1954) reveal that for the molecules in the special positions, the separation between overcrowded carbon atoms is 2 9 A and for the molecules in general positions, 3-1 A. The experimental accuracy is between 0T and 0-2 A, and the mean value of these separations, 3-0 A, may be taken as indicating the magnitude of the displacement. This distortion is achieved with no major changes in bond angles or severe buckling of any benzene ring (Fig. 18). The... 

Figure 14. Hydrophobicity analysis of five P-type ATPases according to the Kyte-Doolittle method. A hydrophobicity value between -4.5 and +4.5 is assigned to each type of amino acid residue and mean values are successively calculated along the peptide sequence using a window of 18 residues. Segments corresponding to the transmembrane helices M1-M10 in the structural model in Figure 15 are shaded. Modified from Verma et al., 1988.

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