Reduced characteristic ratio

The redox ratio R, used to express the oxidizing or reducing characteristics of the exhaust gas mixture, is defined as follows ... 

The characteristic ratios of stereoirregular 1,4-poiybutadiene and 1,4-polyisoprene chains are theoretically investigated by the Monte Carlo procedure in accordance with the model proposed by Mark (V 001 and V 003). It is pointed out that the presence of discrete cis units in frans-rich chains significantly reduces the characteristic ratio while that of discrete trans units in c/is-rich chains has little effect on the characteristic ratio. The characteristic ratio and its dependence on both the trans and cis contents and their sequence distribution is calculated for stereoirregular polymers in accordance with the interdependent RIS model proposed by Mark (V 001 and V 003), and Ishikawa and Nagai V 005 and V 007 . 

The unperturbed dimensions and characteristic ratios of PTMPS chains are calculated using the RIS approximation. The low experimental value of the characteristic ratio reported for this polymer is successfully Interpreted by these computations. The stiffening effect expected from introduction of thep-phenylene group into the chain backbone is apparently offset by its reducing the repulsive Interactions that would otherwise occur among the atoms or groups before and after it eiong the chain. 

The recent theoretical treatment proposed by Miller, Brant and Flory (56) of polypeptide chains containing glydde and aminoacid side chains with branched arbon atoms indicates, as mentioned above that a small number of glycine residues markedly reduces the characteristic ratio, but that a small number of branched side chains does not exert much influence. The figure obtained by Tanford et al., even considering its experimental error of 10% (which is normal), and its origin in the application of the Stockmayer and Fixman equation to low molecular weight samples, is well within theoretical predictions and provides a conclusive test of these. 

Also apparent from Fig. 17.5 is the close agreement between the 272 bond poly(oxyethylene) and the 4 000 bond random flight chains when plotted on the reduced distance scale. As the characteristic ratios C of these two chains are quite different (4 vy 1, respectively), the results suggest that the molecular structure of the chain does not drastically influence the segment density vs distance curves plotted in this reduced fashion. This conclusion requires further confirmation. 

The characteristic ratio C o contains all steric hindrance factors that reduce a freely jointed chain to a polymer chain in its unperturbed dimensions. The characteristic ratio is listed for a lot of polymers in the Polymer Handbook [48]. The num-... 

If all torsional angles were assumed to be equally probable, cos (f> = 0 and the equation (2.28) reduces to equation (2.27). The characteristic ratio Coo therefore takes into account all local or short-range steric interactions and is a measure of the flexibility of the polymer chain. Very flexible chains will have values of Coo close to unity. Typical values of Coo are 6.7 for polyefiiy-lene, 10.2 for polystyrene, and about 600 for DNA — much higher than the... 

In the case of areal electrodes, as shown in Figures 5.2(a) and (c), the out-of-plane shear modes suggest, for the small characteristic ratio of thickness to the other extents of the laminae, the assumption of unidirectional electric field strength in polarization/through-thickness direction, compare with Figure 4.8(b). When only planar stress in the plane transverse to the polarization direction is regarded, then the constitutive relation an nvay reduces to Eq. (4.28). 

The high C/H ratio for heavy fuels and their high levels of contaminants such as sulfur, water, and sediment, tend to reduce their NHV which can reach as low as 40,000 kJ/kg by comparison to the 42,500 kJ/kg for a conventional home-heating oil. This characteristic is not found in the specifications, but it is a main factor in price negotiations for fuels in terms of cost per ton. Therefore it is subject to frequent verification. 

The cross-flow-tower manufacturer may effec tively reduce the tower characteristic at very low approaches by increasing the air quantity to give a lower L/G ratio. The increase in air flow is not necessarily achieved by increasing the air velocity but primarily by lengthening the tower to increase the air-flow cross-sec tional area. It appears then that the cross-flow fill can be made progressivelv longer in the direction perpendicular to the air flow and shorter in the direction of the air flow until it almost loses its inherent potential-difference disadvantage. However, as this is done, fan power consumption increases. 

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