Relative Preference

The relative preference for the axial orientation for a-halocyclohexanones can also be interpreted in stereoelectronic terms. In 2-chlorocyclohexanone, the axial arrangement... 

Resins currently available exhibit a range of selectivity s and thus have broad application. As an example, for a strong acid resin, the relative preference for divalent calcium ions (Ca ) over divalent copper ions (Cu ) is approximately 1.5... 

When materials are evaluated against each other, the flexural data of those that break in the test cannot be compared unless the conditions of the test and the specimen dimensions are identical. For those materials (most TPs) whose flexural properties are calculated at 5% strain, the test conditions and the specimen are standardized, and the data can be analyzed for relative preference. For design purposes, the flexural properties are used in the same way as the tensile properties. Thus, the allowable working stress, limits of elongation, etc. are treated in the same manner as are the tensile properties. 

The inner hydrophobic core of a membrane can be modelled by the use of an organic solvent. Similarly a water or aqueous buffer can be used to mimic the aqueous filled compartment. If the organic solvent is not miscible with water then a two-phase system can be used to study the relative preference of a compound for the aqueous (hydrophiHc) or organic (hydrophobic, lipophilic) phase. 

Andelt, W. F., Baker, D. L., and Burnham, K. P. (1992). Relative preference of captive cow elk for repellent-treated diets.Journal of Wildlife Management 56,164-173. 

Patterson and Holm also observed that rigid planar quadridentate or related planar bis-chelate complexes, and complexes differing only in donor atoms, are more readily reduced in the order N4 < N2O2 < N2S2. This observation reflects the relative preference of Cu(II) for these donor atoms in the order N > O > S. Patterson and Holm noted that binuclear complexes were... 

The standard economics model, in contrast, assumes that intertemporal preferences are time consistent People s relative preference for well-being at an earlier date over a later date is the same no matter when they are asked. In the example above, such time consistency would require that, irrespective of the specific choice, people make the same choice on February 1 and April 1. The standard economics model therefore, a priori, rules out self-control problems. 

Satterfield s studies indicated that, as the temperature was increased, the preference for adsorption of THs becomes larger (125), but the differences between authors is far more than can be explained by the different temperatures of their experiments. The various parameters are summarized in Table XV. The report of Froment may provide the best guidelines at present (104). That report indicates the following relative preferences for adsorption on the direct desulfurization site (cr) ... 

Examining the table, one can see that the relative preference for sorptions are the following ... 

The reactivity ratios, rA and rB, express the relative preference of a growing chain for one of the two monomers. In free-radical copolymerizations they are roughly independent of solvent, initiator, and temperature. In ionic copolymerization, however, they depend strongly on the counterion and the solvent. 

As seen from Table XIV, the rf mode is always preferred, its relative preference increasing in the series Ag < Ni < Fe/W from 5 to 15 kcal/ mol. Indeed, on clean metal surfaces, the bridge rf coordination has... 

Chromatographic selectivity is based heavily on the phenomenon that each component in a mixture ordinarily interacts with its environment differently from other components under the same conditions. In fact, the separation performed using a separatory funnel and two immiscible solvents employs the same principle that is the basis of liquid chromatography—the relative preference of compounds in one phase for a second phase. This implies that with the proper mobile phase conditions and column packing, various components in the sample will travel through the column differently than others, resulting in the desired separation. 

The reactivity ratios, r, = knlkl2 and r2 = kjk2l, are extremely important quantities, expressing the relative preference of the radical species for the monomers. If r, is greater than 1, for example, it means that a chain with a terminal radical of type 1 would rather add another monomer of type 1 than a monomer of type 2. Furthermore, the reactivity ratios are the only two independent rate variables that we need to know or measure, as opposed to the four individual rate constants. 

The allylic oxidation of alkenes by O2 involves an ene reaction, and proceeds with rearrangement s as in Scheme 4. The intermediate allylic hydroperoxide (5) can be reduced to yield an allylic alcohol (6), or be treated with base to give an unsaturated carbonyl conqiound (7). The reaction works best on tri- or tetra-substituted alkenes, and the relative preference for attack is Me - CH2 CH. The O2 allylic oxidation has been used in the synthesis of a large number of natural products, including some naturally occurring allylic hydroperoxides. It is possible that O2 reactions of this type are involved in biosynAetic processes. 

Part of these data on inform us about the relative preference of SL over LL Interactions, which is related to the difference between the Hamaker constants and Aj. Particularly with water as the liquid, the molar enthalpy of wetting can act as a measure of the otherwise vague notion of surface... 

Stolte, W., and Riegman, R. (1996). The relative preference index (RPI) for phytoplankton nitrogen use is only weakly relatd to physiological preference. J. Plankton Res. 18, 1041—1045. 

Figure 4.4. Surface tensions of binary mixtures according to the exchange principle. Monolayer approximation (eq. [4.2.17]) with fixed areas per molecule. Capacity factor (F ) corresponds to 0.4 nm /molecule. Exchange constant K is a measure of the relative preference of the two components for the surface according to [4.2.10]. Top curves plotted with respect to y s 0 bottom absolute value Ay of the deviation from linearity.

The monomer sequence is governed by the relative preference of monomer A to add to a growing polymer chain-end containing the same monomer P-A (where P is the rest of the polymer chain) or the comonomer B (in P-B) as illustrated in Fig. 11. This preference is described by reactivity ratios ri and r2, the ratios of the rate constants for the addition of similar and dissimilar monomer units at the growing chain-end. 

Dithioles with hydroxy and thiol substituents are protonated forms of l,2-dithiole-3-ones (2a) and -3-thiones (2b) respectively, which are regenerated on deprotonation. The reactions with nucleophiles of 3-alkoxy and 3-alkylthio-1,2-dithiolium salts give dealkylation products only in minor amounts. Instead, nucleophilic attack occurs on the ring (Section 3.11.4.2(iv)). A l,2-dithiolium-4-thiolate (98) readily acylates on an amine function to form a l,2-dithiolo-l,2-dithiole (99). This unusual reactivity is explained by the relative preferences for cyclic and acyclic forms of mesoionic forms <91EGP293120>. 

The relative preference for octahedral or tetrahedral coordination is partly steric, but ligand field... 

Calculations (MP2/6-31G ) allowed an estimate of the relative preference for 15 and 16 to place the alkoxy and methyl groups pseudoaxially and pseudoequatorially, respectively. Compound 15 placed the benzyloxy group pseudoaxial, with a 5.3kcalmol 1 preference, whereas 16 resided in a conformation placing the methyl pseudoequatorial with a modest l.Okcalmol-1 preference. 

The incoming ligand is less tightly bound than the solvent molecule. In this case the relationship between complex stability and cation size is reversed, since the relative preference for the solvent molecule increases with decreasing metal ion radius. 

FIGURE 81 Statistical distribution of LCB within the MW distribution as determined from model calculations based on random incorporation. A Single-site catalyst having Mw/Mn— 2.0, B Cr/silica catalyst having MW/MN 83, assuming that sites exhibit the same relative preference for macromer incorporation as for 1-hexene. 

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