Relationship INDEX

Structure-Activity Relationship Index = SAR Index Stmcture/Response Correlations... 

Another index for evaluating presence of activity cliffs is the SAR Index (or Structure-Activity Relationship Index), defined as a function of two separately calculated scores that assess intraclass diversity and activity differences of similar compounds [Peltason and Bajorath, 2007] ... 

The relationship between the flowrate (Q) towards the well and the pressure drawdown is approximately linear, and is defined by the productivity index (PI). 

B Mohney and L B Kier 1991. The Electrotopological State An Atom Index for QSAR. ntitative Structure-Activity Relationships 10 43-51. 

Solvents exert their influence on organic reactions through a complicated mixture of all possible types of noncovalent interactions. Chemists have tried to unravel this entanglement and, ideally, want to assess the relative importance of all interactions separately. In a typical approach, a property of a reaction (e.g. its rate or selectivity) is measured in a laige number of different solvents. All these solvents have unique characteristics, quantified by their physical properties (i.e. refractive index, dielectric constant) or empirical parameters (e.g. ET(30)-value, AN). Linear correlations between a reaction property and one or more of these solvent properties (Linear Free Energy Relationships - LFER) reveal which noncovalent interactions are of major importance. The major drawback of this approach lies in the fact that the solvent parameters are often not independent. Alternatively, theoretical models and computer simulations can provide valuable information. Both methods have been applied successfully in studies of the solvent effects on Diels-Alder reactions. 

A number of physical chemistry relationships, not enumerated in other sections see Index), will be discussed in this section. 

Citation Searching. In the scholarly Hterature, authors cite earHer pubHcations that relate to the work being reported, thus a subject relationship exists between the citing and cited Hterature. This relationship has formed the basis for the Science Citation Index and related products, developed by the Institute for Scientific Information. Known as Scisearch in its on-line version, the Science Citation Index has become an important information retrieval tool in the second half of the twentieth century. It has been used for straightforward subject searching, in which mode it complements traditional indexed databases and indexes. It has also become a popular tool for hihliometric studies of various sorts, such as attempts to measure the relative impact of research carried out by different individuals or organizations, or the relative impact of pubHcations in different journals. 

There are relationships between the independent size separation device parameters and the dependent size separation efficiencies. For example, the apparent bypass value does not affect the size distribution of the fine stream but does affect the circulation ratio, ie, the ratio of the coarse stream flow rate to the fine stream flow rate. The circulation ratio increases as the apparent bypass increases and the sharpness index decreases. Consequendy, the yield, the inverse of the circulating load (the ratio of the feed stream flow rate to the fine stream flow rate or the circulation ratio plus one), decreases hence the efficiencies decrease. For a device having a sharpness index of 1, the recovery efficiency is equal to (1 — a). 

ICUMSA (1) has adopted tables showing the relationship between the concentration of aqueous solutions of pure sucrose, glucose, fmctose, and invert sugar and refractive index at 20.0°C and 589 nm. 

Equations have been developed that determine the relationship of the refractive index of sucrose solutions between 0—85% concentration, 18—40°C, and 546—589 nm. 

Calcium Carbonate Protective Scale. The LangeHer saturation index (LSI) is a useful tool for predicting the tendency of a water to deposit or dissolve calcium carbonate. Work pubHshed in 1936 deals with the conditions at which a water is in equiHbrium with calcium carbonate. An equation developed by LangeHer makes it possible to predict the tendency of calcium carbonate either to precipitate or to dissolve under varying conditions. The equation expresses the relationship of pH, calcium, total alkalinity, dissolved soHds, and temperature as they relate to the solubiHty of calcium carbonate in waters with a pH of 6.5—9.5 ... 

Water Content and Refractive Index. The water content of a hydrophilic contact lens is a determinant of other properties. The relationship of water content and Dk is discussed above. Water content in lenses is inversely related to refractive index (23), a key property for vision correction. A lens material with a higher refractive index refracts light to a greater degree, allowing more vision correction with a thinner material. The water content of a lens is generally determined gravimetricaHy or inferred from the relationship to refractive index, measured with a refractometer (24). 

The Separation Stage. A fundamental quantity, a, exists in all stochastic separation processes, and is an index of the steady-state separation that can be attained in an element of the process equipment. The numerical value of a is developed for each process under consideration in the subsequent sections. The separation stage, which in a continuous separation process is called the transfer unit or equivalent theoretical plate, may be considered as a device separating a feed stream, or streams, into two product streams, often called heads and tails, or product and waste, such that the concentrations of the components in the two effluent streams are related by the quantity, d. For the case of the separation of a binary mixture this relationship is... 

Correlation methods discussed include basic mathematical and numerical techniques, and approaches based on reference substances, empirical equations, nomographs, group contributions, linear solvation energy relationships, molecular connectivity indexes, and graph theory. Chemical data correlation foundations in classical, molecular, and statistical thermodynamics are introduced. 

Produet toleranee ean signifieantly influenee produet variability. Unfortunately, we have dilfieulty in finding the exaet relationship between them. An approximate relationship ean be found from the proeess eapability index, a quality metrie interrelated to manufaeturing eost and toleranee (Lin et al., 1997). The random manner by whieh the inherent inaeeuraeies within a manufaeturing proeess are generated produees a pattern of variation for the dimension whieh resembles the Normal distribution (Chase and Parkinson, 1991 Mansoor, 1963) and therefore proeess eapability indiees, whieh are based on the Normal distribution, are suitable for use. See Appendix IV for a detailed diseussion of proeess eapability indiees. 

The critical characteristic on each component was analysed, calculated from the analysis and the value obtained was plotted against the process capability indices, Cpk and Cp, for the characteristic in question. See Appendix V for descriptions of the 21 components analysed, including the values of Cp and Cp from the SPC data supplied. Note that some components studied have a zero process capability index. This is a default value given if the process capability index calculated from the SPC data had a mean outside either one of the tolerance limits, which was the case for some of the components submitted. Although it is recognized that negative process capability indices are used for the aim of process improvement, they have little use in the analyses here. A correlation between positive values (or values which are at least within the tolerance limits) will yield a more deterministic relationship between design capability and estimated process capability. 

Note that the squared relationship which was initially used to model the degree of difficulty in obtaining more capable tolerances for a given manufacturing route and product design is being returned by the power law. Similarly, a relationship between the process capability index Cp and q for the components analysed is shown in... 

The ratio PVC/CPVC (or reduced CPVC) is a simple but profound index of primer film structure that is perhaps the most important parameter in all of paint technology [70]. The relationship of the reduced CPVC to film structure can be appreciated by reference to Fig. 8. This figure shows a representation of a dry primer film with a range of pigment volume fraction that increases from left to right. 

Fig. 1. (a) Geometrical relationship between incident electron beams in TEM and CNT, (b) typical TED pattern, (e) schematic illustration of image of CNT and (d) ero.ss-seetional view of CNT. In the TED pattern, the indexes follow those of graphite. 

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