An Approach to the Problem

In many cases, it is useful to have some way to approximate the polarity of a molecule or a portion of the molecule. For this purpose, knowing the polarity of specific bonds can provide an approach to the problem. Table 6.2 shows the bond moments for numerous types of bonds. 

These Xpjr groups represent an especially difficult problem because their delocalized electrical effect depends on the steric effect when they are bonded to planar jr-bonded skeletal groups, Gp7r. An approach to the problem has been developed45,46. The electrical effect parameters are a function of the dihedral angle formed by Xp3r and Gpn. The relationship generally used has the form ... 

Masson C. R. (1965). An approach to the problem of ionic distribution in liquid silicates. Proc. Roy. Soc. London, A287 201-221. 

An approach to the problem is summarized in eq. (3). Aldehydes are subject to catalytic olefination when certain aliphatic diazoalkanes are used as alkylidene group transfer reagents phosphines are necessary to carry off the 0x0 group. 

The methods of statistical mechanics (24,22) have provided an approach to the problem of gas-metal solubility. The metal can be regarded as containing a series of holes of low... 

An approach to the problem of how to apply LEFM parameters to concretes, which neither behave as linear elastic bodies nor are they isotropes, and to specimens of relatively small dimensions is proposed in the Draft Recommendations published by the Technical Committee 89-FMT of RILEM (1990a) and (1990b). In the first of them the method of determination of... 

Both theoretical [2,3] and experimental [4] efforts have been made to understand such solvation interactions. Central to the study of this problem of interaction of a solute and its local environment is the question of how the free energy of a solute changes due to the presence of surrounding interacting molecules of the medium. An approach to the problem at a molecular level is fraught with... 

Molecule enumeration has been discussed in the scientific literature since Cayley proposed an approach to the problem in 1875. The last 120 years have seen the periodic resurgence and decline of interest in this topic. The 1930s saw breakthroughs in the field of acyclic molecule counting by Blair and Polya. A profound resurgence of interest occurred in... 

Many comprehensive schemes for separation of commercial products have been published. These attempt the systematic identification of every ingredient in a formulation by a single general approach and are represented by flow charts of as many as a dozen steps. These methods are very valuable in the laboratory of the originator, but are not easily translated to other locations where the nature of the samples and the equipment available to the analyst differ. These general schemes are not covered here. We limit our discussion to separation of only a few components at once, allowing the reader to tailor an approach to the problem at hand. 

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