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Interrelationships of the data

Just as a relationship exists between the various properties of petroleum with parameters such as depth of burial of the reservoir (Speight, 1999), similar relationships exist for the properties of coal (e.g., Solomon, 1981 Speight, 1994). Variations in hydrogen content with carbon content or oxygen content with carbon content and with each other have also been noted. However, it should be noted that many of the published reports cite the variation of analytical data or test results not with rank in the true sense of the word but with elemental carbon content that can only be approximately equated to rank. [Pg.12]

TABLE 1.6 Analytical Specifications for Coal from Selected U.S. Mines  [Pg.13]

Mine/Owner Btu/lb Sulfur (%) Ash (%) Moisture (%) Volatile Matter (%) Fixed Carbon (%) [Pg.13]

Finally, it is also possible to illustrate the relationship of the data from proximate analysis and the calorific value to coal rank. [Pg.14]


Clearly, the user of any thermodynamic tables must become familiar with the tables and the interrelationships of the data if he plans to make extensive use of the values. Moreover, he must not use them blindly. The actual numbers tabulated for the different thermodynamic functions are not so significant as the final equilibrium constants that are to be calculated from them. These tables are designed to yield equilibrium constants of as high an accuracy as can be obtained from the available data. Thus, the uncertainty of a given heat of sublimation may be considerably smaller in regard to its use for calculation of vapor pressures than in regard to its use for heat balance calculations. [Pg.2]

The interrelationships of the various coefficients associated with fluid uptake (Section 23.4.2) mean that it should be possible to estimate a rate for one of the uptake phenomena from test data for another of them. Campion proposed using this approach to estimate permeation coefficient Q from solubility coefficient s. The form of a liquid absorption plot (Figure 23.6, Section 23.4.4.1) is such that s should be obtainable from it, and inspection showed that this link was via Henry s law with concentration corrected by the polymer density p. The following expression was derived for s ... [Pg.641]

It is also beyond the graphical representation capabilities commonly used. Factor analysis is one of the pattern recognition techniques that uses all of the measured variables (features) to examine the interrelationships in the data. It accomplishes dimension reduction by minimizing minor variations so that major variations may be summarized. Thus, the maximum information from the original variables is included in a few derived variables or factors. Once the dimen-... [Pg.22]

The initial step in the analysis of the data generally requires the calculation of a function that can indicate the degrees of interrelationship that exist within the data. Functions exist that can provide this measure between either the variables when calculated over all of the samples or between the samples calculated over the variables. The most well-known of these functions is the product-moment correlation coefficient. To be more precise, this function should be referred to as the correlation about the mean. The "correlation coefficient" between two variables, Xj and Xj over all n samples is given by... [Pg.24]

Develop models for scenarios and acquire data. The release and exposure scenarios described above are evaluated through modeling. The models embody the mathematical interrelationships of the possible steps in each scenario. Simplifications and approximations usually are introduced to reflect limitations in knowledge and data or the results of previous risk assessments that show certain scenarios and pathways to be negligible. The result often is a series of models describing (1) degradation of... [Pg.89]

A statistical model consists of a set of assumptions about the nature of the data to be collected in the trial and about the interrelationships among various variables. These assumptions must be specific enough that they could be expressed by a set of mathematical expressions and equations. [Pg.325]

In addition, there are many instances in which interrelationships of the specification data enable properties to be predicted from the measured properties with as good precision as can be obtained by a single test. It would be possible to examine in this way the relationships between all the... [Pg.16]

The structure of pandoline (37), isolated from Pandaca calcarea and P. debrayi, has been established as (37) and confirmed by chemical interrelationship with catharanthine. Here again the structure assignments relied heavily on n.m.r. evidence comparisons of the data (p. 190) on (37) with those for the aspidosperma alkaloid vincadifTormine (31) will illustrate this point. Thus, for example, the chemical shift of C-20, being 49 p.p.m. downfield from its position in (31), showed this to be the hydroxy-bearing carbon that this carbon was also shown to be quaternary confirmed the presence of the ethyl at this same position. [Pg.219]

In addition, the optional punching of the results permits statistical analyses for a group of films. Cards from both low- and high-density runs may be combined with other data to obtain a profile of mean values for each variable, and to study the interrelationships of the various segments of the lipoprotein spectrum. This aspect will be touched upon in tiie next section. [Pg.44]

The observations reported in this chapter provide support for, and facilitate the interpretation of, the wealth of data amassed from studies on the olfactory system begun almost 250 years ago (cf. Kleerekoper, 1982) which have dealt with the description of the structure of the olfactory epithelium, the neuroanatomical links between the nose and the brain, the importance of scent and pheromone detection in animal behavior, and with experimentally induced changes in the olfactory system. Much of the work we have presented is in its early phases of study. Thus, this chapter is not meant to be definitive, but rather we hope that by presenting new concepts, approaches and questions, we will serve to instigate study (perhaps with a different direction, scope or emphasis) on the structural and functional interrelationships of the olfactory and reproductive systems in all classes of vertebrates. [Pg.168]

Among the most important requirements in the theory of chemical bonds is the development of a unified method for the description of the chemical interaction between atoms, which would be based on the structure of the atomic electron shells and in which one would utilize the wave functions and the electron density distributions calculated for isolated (free) ions on the basis of the data contained in Mendeleev s periodic table of elements. This unified approach should make it possible to elucidate the interrelationship between the various physical properties and the relationship between the equilibrium and the excited energy states in crystals. In contrast to the study of chemical bonds in a molecule, an analysis of the atomic interaction in crystals must make allowances for the presence of many coordination spheres, the long- and short-range symmetry, the long- and short-range order, and other special features of large crystalline ensembles. As mentioned already, the band theory is intimately related to the chemi-... [Pg.170]

This work produced one inescapable conclusion of absolute importance. The main problem in parameter optimization was not the mechanics of optimization (modem optimization methods and the development of more powerful computers had made that task easily tractable), rather what was important was the construction of a valid reference data set. Such a data set would need to be sufficiently diverse as to allow all the parameters in the method to be defined. This is not a trivial task. Inspection of the parameters yields information regarding the types of property they influence, but the interrelationship of parameters and properties is extremely complicated, and the composition of the data set cannot be deduced merely by an examination of the parameters. [Pg.2083]


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See also in sourсe #XX -- [ Pg.12 ]




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Data interrelationships

The Data

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