Correlations with other properties

It is especially important to investigate the molecular structure of coordination compounds in the vapor phase because the relatively weak coordination interactions may be considerably influenced by intermolecular interactions in solutions and especially in crystals. It has been shown that the geometrical variations can be correlated with other properties of the molecular complexes ). In particular the structural changes in the F3B N(CH3)3 and CI3B N(CH3)3 molecules ) relative to the respective monomeric species unambiguously indicated boron trichloride to be a stronger acceptor than boron trifluoride. Data on the geometry and force field have also been correlated ). 

Brisance Tests. See under Brisance, Correlation with Other Properties... 

As the In concentration increased, the degree of crystallinity (measnred by the height of the XRD peaks) and crystal size increased, reached a peak, and then decreased. These structural changes correlated with other properties The bandgap and resistivity were minimum when the crystallinity and crystal size were maximum. The concentration of In in the films was much higher than that in solution (>2% of the Cd concentration, compared to 0.1% in the solution)... 

Laboratory research in this area is conducted by suspending a porous box of desiccant very close to the surface of a film balance. The rate of water uptake is determined by weighing at various times. This way the retardation of evaporation may be measured as a function of film pressure and correlated with other properties of the monolayer determined by the same method. As might be expected, the resistance to evaporation that a monolayer provides is enhanced by those conditions that promote the most coherent films, most notably high film pressures and straight-chain compounds. To see how this is quantified, consider the Example 7.3. 

Expressible moisture and water uptake ability measure different properties. Figure B5.3.2 shows the very different cation and anion dependencies of these methods using fish samples. Figure B5.3.3 shows that the pH profiles are also different. It is also apparent that WUA is often >100%, while expressible moisture must, of necessity, be <100%. Figure B5.3.4 shows an example where expressible moisture was actually correlated with a separate and independent functional measurement. In this case, the binding of cooked fish muscle as determined by a subjective sensory panel pulling samples of fish apparently paralleled the moisture retention of the raw fish (moisture retention = 1 - expressible moisture). Ideally, functional properties should show such correlations with other properties of interest in food systems. 

The correlation of k or Egct with bond strengths are the most commonly used for estimation purposes but correlations with other properties of the molecules are possible. For example, it is possible to correlate the rate constant for OH + alkane reactions with the ionization potential of the alkane [10] and, for other types of reaction, it has been suggested that both electron affinities and ionization potentials of the species involved may correlate with the kinetics parameters [51]. However, because of the great sensitivity of the rate constant to small errors in Eact, correlations aimed at predicting Eact are very rarely used. 

These tests, as indicators of stretchability, should correlate with the n value, but the correlation is unsatisfactory. A better correlation with the total elongation and reduction in area can be obtained. These tests have the drawbacks of poor reproducibility of results and poor correlation with other properties or service/... 

Generally, changes in resilience are fairly modest although, where the initial level is low, they appear large in percentage terms. Perhaps surprisingly, most compoimds increased in resilience. Exceptions are natural A, and acrylate S for which resilience consistently fell. There is no apparent simple pattern of correlation with other properties. 

Hardness measurements such as Rockwell or Vicker s indentation properties are time-dependent as a result of the viscoelastic flow and relaxation processes (236) (see Hardness). Microhardness measurements have been used to correlate with other properties such as Yoimg s modulus and compressive yield stress in polyethylenes (237) and glass-transition temperature of amorphous plastics (238). Scratch resistance in polyproplyene studies was found to have shear yielding as the main cause of plastic flow scratch pattern with tensile tear effects on the surface and shear-induced fracture on the subsurface (239). 

Das, K., Ray, D., Baneijee, I., Bandyopadhyay, N.R., Sengupta, S., Mohanty, A.K., Misra, M., 2010. Crystalline morphology of PLA/clay nanocomposite films and its correlation with other properties. Journal of Applied Polymer Science 118, 143—151. 

Density, relative density (specific gravity), or API gravity is a factor governing the qu ty of crude petroleum crude petroleum prices are frequently posted against values in degrees API. However, this property of petroleum is an uncertain indication of its qudity u ess correlated with other properties. 

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