The phase transitions for 90 were also evident in the UV-VIS spectra, as seen in Figure 26 M has an absorption maximum at 315 nm, QM at 350 nm, and multiple absorptions with peaks at ca. 315, 350, 365, and 378 nm are evident for phase I and the other phases. Isosbestic points observed between the phases indicate coexistence of two states during structural evolution, and the existence of multiple UV peaks for a phase is considered to indicate the existence of several conformations for that phase. In this report, 0 all structures were modeled with conformations between all-T and all-D thus, the conformational nature of the different phases of (Si-/z-Dec2U is not clear. Similar UV absorptions observed for structurally related polymers, such as PDHS (see below), are suggestive of comparable backbone conformations. [Pg.601]

Due to the favorable conformation for multiple H-bonds, tren-based tripodal tris (urea) receptors, including 38a-j, have proven to be a promising scaffold for anion binding. Such receptors not only complementarily encapsulate oxoanions (sulfate, carbonate, and phosphate) but also display excellent binding ability to spherical halide ions. Several groups studied tripodal trisurea receptors with different substituents. [Pg.154]

In all of the 3D search methods the conformational flexibility creates considerable difficulties. Large databases of multiple conformations for each structure have been developed which make the solution of this problem possible. [Pg.314]

Matrix multiplication is based on the dot product defined for any two vectors of equal size. The product matrix P of two conformally sized matrices K and L is a matrix of size number of rows of K by number of columns of . To be compatible for multiplication, the rows of K and the columns of L must have the same length. If this is so then the entries pij of the matrix product P = K L = (pij) are computed as the dot products of row i of the first matrix factor K with the column j of the second matrix factor L. We refer the reader to the annex on matrices. [Pg.16]

Matrix multiplication Two matrices, A and B, are said to be conformable for multiplication in the order AB if A has the same nnmber of colnmns as B has rows. The multiplication is defined by [Pg.83]

Wiens, B. L., Nelson, C. S., and Neve, K. A. (1998). Contribution of serine residues to constitutive and agonist-induced signaling via the D2S dopamine receptor Evidence for multiple, agonist-specific active conformations. Mol. Pharmacol. 54, [Pg.134]

The analysis of relations between intensities in the region of double bond stretching vibrations >c=n in the Raman spectra, allows one to arrive at a conclusion about s-cis- or s-trans -conformation of multiple bonds. The ratio between intensities of the high-frequency band to the low-frequency one for s-trans -conformers appears usually to be more than 0.5, whereas for s-cis -conformers it is less than 0.25 (393, 394). [Pg.190]

Can a rectangular matrix be both premultiplied and postmultiplied into its own transpose, or must multiplication be either pre- or post- for conformability If multiplication must be either one or the other, which is it [Pg.91]

Prove that tr(AB) = tr(BA) where A and B are any two matrices that are conformable for both multiplications. They need not be square. [Pg.115]

This permits enor analysis of that vector. (Note that the order Xm is necessary for the mahix and vector to be conformable for multiplication.) Repeating the procedure for all m vectors leads to error analysis of the entire matrix M. [Pg.86]

Here each entry denotes a subarray and is shown accordingly in bold type. Thus, the vector x is partitioned here into two subvectors, and the matrix A is partitioned into six submatrices. The submatrix Ahk contains the coefficients in the row subset h for the elements of the subvector Xk, thus, these arrays conform for multiplication in the order written. [Pg.180]

The product of two matrices AB exists if and only if the number of rows in the second matrix B is the same as the number of columns in the first matrix A. If this is the case, the two matrices are said to be conformable for multiplication. If A is an mxp matrix and B is a pxn matrix, then the product C is an mxn matrix [Pg.397]

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