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The Complexity Distribution

The Complexity Distribution. —The number of molecules composed of n branch units irrespective of the number I of bifunctional units, which we have called the complexity distribution, may be obtained by summing over all I in Eq. (A-8). A more intuitive approach to the same result will be followed here. We consider the probability a that an A group of one branch leads via a sequence of zero or more A----A units to another branch. [Pg.395]

The probability a that an unreacted A group selected at random leads [Pg.395]

From here on the deduction of the probability Fn that the arbitrarily selected unreacted A group is part of a molecule containing n branch units proceeds identically with the deduction of Fx for the simple /-functional distribution. Hence [Pg.396]

For the purpose of deriving the weight fraction distribution, attention is directed to the fact that a molecule containing n /-functional branches is composed oi fn—n+1 chains. The average size of a chain being independent of the location of the chain in a branched structure, the quantity fn — n + 1 may be taken as a measure of the average weight of an n-chain polymer. It follows that [Pg.396]

The total number of chains, being by definition equal to half the sum of the unreacted functional groups and the functional groups attached to branch units, is [Pg.396]


The complex distribution system that results from the frontal analysis of a multicomponent solvent mixture on a thin layer plate makes the theoretical treatment of the TLC process exceedingly difficult. Although specific expressions for the important parameters can be obtained for a simple, particular, application, a general set of expressions that can help with all types of TLC analyses has not yet been developed. One advantage of the frontal analysis of the solvent, however, is to produce a concentration effect that improves the overall sensitivity of the technique. [Pg.453]

It is possible to show that the complexity distribution retains all of the principal characteristics of the distribution for the condensation of A—R—B/ i alone (Fig. 66). Indeed, these are already present in Eq. (30). The major difference has to do with the presence of linear... [Pg.369]

The term cross-fractionation (CF) refers to analyses of distributions in differing directions by means of separation processes. Cross-fractionation is a significant tool for the evaluation of the complex distribution which copolymers normally have with respect to molar mass (MMD) and chemical composition (CCD). The idea of CF implies separation by one parameter and subsequent analysis of the fractions obtained for the distribution of the other parameter through another separating process. [Pg.204]

FIGURE 6 Schematic representation of an oxide catalyst with its functional compartments in various structural states for high (back) and low (front) chemical potentials of oxygen. The arrows and the question mark indicate the complex distribution of oxygen in its dual role as a reactant at the surface and as a constituent of the catalyst material in the bulk. Its abundance is controlled by the presence of reducing species in the gas phase leading to a dependence of the results of XRD structural analysis on the availability of reducing gas-phase species. For details and references, see the text. [Pg.285]

The complexity of natural processes in subducting slabs is reflected by the complex distribution of volcanic emissions in subduction zones. First, it should be emphasized that 69% of modem subduction zones on the Earth (40,900 km, unpublished compilation) show active volcanism in the Quaternary. The rest (18,500 km) are not volcanic because of either unfavorable thermomechanical environments (e.g., flat slabs, initiation of subduction, etc.) or possibly the lack of a sufficient amount of volatiles released at depths where melting could take place. [Pg.1843]

Figure 2.50. The illustration of the complex distribution of reciprocal lattice vectors modeled using a spherical harmonic preferred orientation function for the (100) reflection. Figure 2.50. The illustration of the complex distribution of reciprocal lattice vectors modeled using a spherical harmonic preferred orientation function for the (100) reflection.
The complexity of a molecule is defined as the number A b of/-functional units in a molecule. The complexity distribution is therefore... [Pg.248]

Show that the complexity distribution is similar to the simple /-functional... [Pg.248]

For L-dopa melanin i// equals 1.26. This value cannot be explained by the use of simplified approximations, thus reflecting the complex distribution of shapes and sizes of the pigment granules. Such studies on natural pigments are rather limited owing to the possible interference of proteins and other strongly bound cellular components to the IR spectra of melanins. [Pg.298]

The complex distribution system that results from the frontal analysis of a multicomponent solvent mixture on a thin layer plate makes the theoretical treatment of the TLC process exceedingly difficult. Although specific expressions for the important parameters can be obtained for a simple, particular, application, a general set of expressions that can help with all types of TLC analyses has not yet been developed. One advantage of the frontal analysis of the solvent, however, is to produce a concentration effect that improves the overall sensitivity of the technique. The primary parameter used in TLC is the (Rf) factor which is a simple ratio of the distance traveled by the solute to the distance traveled by the solvent front. The (Rf) factor will always be less than unity. If a standard is added to the mixture, then the ratio of the (Rf) factors of the solute to that of the standard is termed the (Rx) factor and is thermodynamically equivalent to the separation ratio (a) in GC or LC. In a similar manner, the capacity ratio (k ) of a solute can be calculated for TLC from its (Rf) factor. Resolution is measured as the distance between the centers of two spots to the mean spot width. Alternative expressions for the resolution can be given in terms of the (Rf) factor and the plate efficiency. The plate efficiency is taken (by analogy to GC and LC) as sixteen times the square of the ratio of the retention distance of the spot to the spot width, but the analogy between TLC and the techniques of GC and LC can only be used with extreme caution. The so called... [Pg.457]

The complex distribution Qg is solved from the simultaneous equations (12) and (13) by iterations. Stiffness coefficients K K and... [Pg.364]

Using the complexity distribution approach and assuming that the proportion of -functional units is small ( << 1), the weight fraction of sol when cx, is... [Pg.366]

Hemoglobin is a globular protein, meaning that it assembles into a roughly spherical shape with polar residues covering most of the sphere s surface and nonpolar residues largely confined to the interior of the complex. Distribution of polar residues on the outside of the sphere enhances a globular protein s aqueous solubility. [Pg.497]

The importance here is to recognise the limitation of the test. In addition to the nonequilibrium temperature of the test and the complex distribution of strain, the curve is measured at 2 rpm, which is an arbitrary time-scale. The material behaviour may be different at other time-scales this situation is exactly like a blind man touching an elephant . In addition, at this time scale the Mooney rheometer is not very sensitive to a small difference between the gum rubbers. Therefore, this method is for the screening and catching only a gross difference among the samples. The Mooney test is performed for the specification in any event, and therefore, it is proposed here to pay attention to the shape of the curves also. [Pg.368]

Owing to the complex distribution among these three cations in transition metal layers, the homogeneity at the atomic level in terms of chemical composition of cobalt, nickel and manganese is the key in the preparation of the electrochemical-preferred LiNii/3Coi/3Mni/302, where the traditional mechanical mixing techniques may not be suitable for synthesis [29]. [Pg.198]


See other pages where The Complexity Distribution is mentioned: [Pg.369]    [Pg.374]    [Pg.397]    [Pg.371]    [Pg.306]    [Pg.311]    [Pg.149]    [Pg.160]    [Pg.2824]    [Pg.183]    [Pg.160]    [Pg.303]    [Pg.327]    [Pg.45]    [Pg.380]    [Pg.306]    [Pg.311]    [Pg.294]    [Pg.365]    [Pg.277]    [Pg.122]    [Pg.63]    [Pg.53]    [Pg.232]    [Pg.87]    [Pg.136]    [Pg.377]    [Pg.4]   


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