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Non-topological parameters

Furthermore, the SAXS is also related to some non-topological parameters of the nanostructure [13,14], They describe the contrast between the phases, [Pg.200]


Automated Extraction of Interference Functions. For the classical synthetic polymer materials it is, in general, possible to strip the interference function from the scattering data by an algorithm that does not require user intervention. Quantitative information on the non-topological parameters is lost (Stribeck [26,153]). The method is particularly useful if extensive data sets from time-resolved experiments of nanostructure evolution must be processed. Background ideas and references are presented in the sequel. [Pg.155]

In Q the non-topological structure parameters of the material s nanostructure are combined. For multiphase systems this fact can be deduced by application of the Fourier-slice theorem and the considerations which lead to Porod s law. In particular, for a two-phase system it follows64... [Pg.147]

The shortcomings of the phantom network concepts have stimulated a number of attempts to find theoretically a more satisfactory elastic free energy function to describe the properties of elastomers at different states of deformation. The efforts to explain the real network behaviour by a special non-topological mechanism can be divided into four types. The first group considered intra- and intermolecular effects los-ni) wjtii these assumptions it is hard to explain values of the Mooney-Rivlin parameter which are of the order of the corresponding Cj parameter. [Pg.49]

Non-specific parameters, physicochemical parameters, and topological indices are the main parameters used in QSRR studies in TLC. The establishment of QSRR equations in TLC are reviewed according to these parameters. [Pg.1980]

The second virial coefficient is not a universal quantity but depends on the primary chemical structure and the resulting topology of their architecture. It also depends on the conformation of the macromolecules in solution. However, once these individual (i.e., non-universal) characteristics are known, the data can be used as scaling parameters for the description of semidilute solutions. Such scaling has been very successful in the past with flexible linear chains [4, 18]. It also leads for branched macromolecules to a number of universality classes which are related to the various topological classes [9-11,19]. These conclusions will be outlined in the section on semidilute solutions. [Pg.120]

In order to reduce the dimension of the model space, several attempts have been made to find associated topological quantum numbers which would allow to separate the covalent VB space into non-mixing different subspaces (see Ref. 30 and references therein). For the linear chain, preliminary attempts were made early in 1979 [31], when a parameter measuring the spin-pairing long-range order was suggested,... [Pg.741]

ZSM-23 is a medium pore high silica zeolite with interesting catalytic and adsorptive properties (1-5). Recently, its framework topology was shown to have orthorhombic symmetry (Pmmn) with unit cell parameters of a = 0.501 nm, b = 2.152 nm and c = 1.113 nm. The pore structure of ZSM-23 consists of linear, non-interpenetrating channels with teardrop shaped openings of ca. 0.45 x 0.56 nm (6). It was proposed to denote this framework topology as MTT (Mobil-twenty-three) (6). Based on a comparison of X-ray powder data, it was suggested that two other zeolites, viz. KZ-1 ( 7) and ISI-4 (8j also possess the MTT framework (6). [Pg.560]

Linear and non-linear correlations of structural parameters and strain energies with various molecular properties have been used for the design of new compounds with specific properties and for the interpretation of structures, spectra and stabilities 661. Quantitative structure-activity relationships (QSAR) have been used in drug design for over 30 years 2881 and extensions that include information on electronic features as a third dimension (the electron topological approach, ET) have been developed and tested 481 (see Section 2.3.5). Correlations that are used in the areas of electron transfer, ligand field properties, IR, NMR and EPR spectroscopy are discussed in various other Chapters. Here, we will concentrate on quantitative structure-property relationships (QSPR) that involve complex stabilities 124 289-2911. [Pg.115]

In the systems (I) and (III) 2-simplex consists of a sole cell, all the trajectories inside which approach SP corresponding to homopolymer Ms where rs < 1. The systems (I) and (III) topologically are equivalent, since they differ from each other only by the inversion of the monomer indexes therefore their phase portraits are of the same type, too. In the systems (II) and (IV) the azeotropic point separates the simplex into the two cells. However, the system (IV), in which both parameters r, and r2 exceed unity practically is non-realizable [20-24]. That is why the stable binary azeotropes are excluded from the consideration, and the dynamics of the copolymerization of two monomers is exhaustively characterized by only two types (I) and (II) of phase portraits. [Pg.36]

In the middle of domains, the overlayers are well ordered, with a lattice parameter very close to that of metallic A1 (expansion of 4 % with respect to the registered state), and a small rotation (-1.4° with respect to the R state) with the epitaxial relationships (111)A1//(0001)A1203 and [Tl0]Al//(R1.4°)[1120]Al2O3. In the domain walls, large expansion and rotation, and even loss of honeycomb network topology were found. The observed structure was interpreted in the spirit of rotational epitaxy with non-linear distortions. [Pg.271]

A geometric steric parameter for the X substituent based on the non-hydrogen atoms of the substituent and their topological distance from the atom to which the substituent is linked [Austel et al, 1979] it is calculated as ... [Pg.412]


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See also in sourсe #XX -- [ Pg.132 ]

See also in sourсe #XX -- [ Pg.132 ]




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