Fragment distribution

Unfortunately, fragmentation by construction does not appear to be independent of the random construction algorithm. An alternative method of successive segmentation (Grady and Kipp, 1985) of the surface, as illustrated in Fig. 8.24 leads to a fragment distribution which agrees well with a linear exponential distribution ((8.59)) and differs significantly from the Mott distribution ((8.58)). 

Figure 8.25. Comparison of Mott, Voronoi, and linear exponential cumulative fragment distributions.

Perhaps the overriding conclusion which emerges from the discussions of fragment distributions in dynamic fragmentation is the difficulty of relating... 

For solution of the population balanee equation, many forms exist for the partiele disruption terms Ba and Da respeetively (Randolph and Larson, 1988 Petanate and Glatz, 1983) but a partieularly simple form, whieh requires no integration of a fragment distribution, is the two-body equal-volume breakage funetion. It is assumed that eaeh partiele breaks into two smaller pieees, eaeh of half the original volume from whieh it follows that... 

Fragment distribution. Figure 9.9a shows the fragment distribution for event group 1. Table 9.13 gives an impression of the distribution of the fragments. 

Fab fragments (M.W. 50,000) have several advantages over IgG (M.W. 150,000) for use as the immunotherapeutic reagent (Smith et al. 1979). The Fab fragments distribute more rapidly and extensively than intact IgG. In addition, they are catabolized and excreted earlier than intact IgG. A final important advantage is that the Fab fragments are less antigenic than the intact IgG. 

Figures 4.6—4.8 are the results for the stoichiometric propane-air flame. Figure 4.6 reports the variance of the major species, temperature, and heat release Figure 4.7 reports the major stable propane fragment distribution due to the proceeding reactions and Figure 4.8 shows the radical and formaldehyde distributions—all as a function of a spatial distance through the flame wave. As stated, the total wave thickness is chosen from the point at which one of the reactant mole fractions begins to decay to the point at which the heat release rate begins to taper off sharply. Since the point of initial reactant decay corresponds closely to the initial perceptive rise in temperature, the initial thermoneutral period is quite short. The heat release rate curve would ordinarily drop to zero sharply except that the recombination of the radicals in the burned gas zone contribute some energy. The choice of the position that separates the preheat zone and the reaction zone has been made to account for the slight exothermicity of the fuel attack reactions by radicals which have diffused into...

The stockholder recipe partitions the density according to each atom s contribution to the promolecule density. The partitioned fragment distributions... 

Table 4.4 Fragment distribution for certain gases at 75 eVand 102 eV...

Despite the fact that the NO fragment distribution has not yet been measured, they have made considerable progress in the understanding of the photodissociation dynamics of this molecule. In the first paper, they were able to show that there is a competition between one-photon and two-photon photodissociation. 

Freed and Band (2) calculated the FC factor with functions 122 and 123 for direct photodissociation and obtained the following dependence for the fragment distribution ... 

Equation (7.22) is at the heart of spectroscopy. The positions of the absorption lines reflect the energy levels of the excited complex and the widths provide information about the lifetime and therefore about the coupling to the continuum states. The latter requires, however, that the measured widths are the true homogeneous line widths, i.e., unadulterated by poor resolution and/or thermal broadening, for example. Each resonance has a characteristic width. In Chapters 9 and 10 we will discuss how the final fragment distributions reflect the initial state in the complex and details of the fragmentation mechanism. 

It is worthwhile, however, pointing out that the existence of a long-lived intermediate state and the absence of a barrier in the exit channel do not necessarily imply statistical product state distributions. The fragment distributions in the dissociation of weakly bound van der Waals molecules are usually neither thermal nor statistical, despite the extremely long lifetime of the complex. We will come back to this in Chapter 12. 

Karakoc, E., Sahinalp, S.C., and Cherkasov, A. (2006) Comparative QSAR- and fragments distribution analysis of drugs, druglikes, metabolic substances, and antimicrobial compounds. J. Chem. Inf. Model. 46,2167-2182. 

Ions and ionized clusters ejected from a surface during ion bombardment are detected with a mass spectrometer. Surface chemical composition and some information on bonding can be extracted from SIMS ion fragment distributions. 

Table 5.2 Fragment distribution pattern of water vapour for ionising electron energy = 102 e V...

Table 5.3 Fragment distribution pattern for several gases for different ionising electron energiesa...

Fig. 11.1 Size and fragment distribution after an explosion with a quantity of 1 g Pb(N3)2 in a 10-ml glass vessel.

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