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Elements, essential variable

Quantities of the square core matrix may eventually appear in all of the dimensionless numbers as fillers, whereas each element of the residual matrix will appear in only one dimensionless number. For this reason the residual matrix should be loaded with essential variables like the target quantity and the most important physical properties and pro-cess-related parameters. [Pg.11]

The nature of the steps which have to be carried out now makes this dimensional matrix less than ideal because it is necessary to know that each of the individual elements of the residual matrix will appear in only one of the dimensionless numbers, while the elements of the core matrix may appear as fillers in the denominators of all of them. The residual matrix should therefore be loaded with essential variables such as the target quantity and the most important physical properties and process-related parameters. Variables with an, as yet, uncertain influence on the process must also be included in this group. If, later, these variables are found to be irrelevant, only the dimensionless number concerned will have to be deleted while leaving the others unaltered. [Pg.17]

The nervous membrane is the wall of the nervous cell. Its excitation is the basic process of the propagation of information along the axons, which are the conduction elements of the nervous cell. The essential variables of the excitation process are... [Pg.13]

The total residual sum of squares, taken over all elements of E, achieves its minimum when each column Cj separately has minimum sum of squares. The latter occurs if each (univariate) column of Y is fitted by X in the least-squares way. Consequently, the least-squares minimization of E is obtained if each separate dependent variable is fitted by multiple regression on X. In other words the multivariate regression analysis is essentially identical to a set of univariate regressions. Thus, from a methodological point of view nothing new is added and we may refer to Chapter 10 for a more thorough discussion of theory and application of multiple regression. [Pg.323]

All of the above essential elements, in non-stoichiometric and maybe somewhat variable ratios, are necessary for structure, energy capture, catalysis, coding, osmotic and electrolyte stability, and confinement in space... [Pg.21]

Since the theory under examination works exclusively on scales essentially exceeding size a of a monomeric unit, the function D(Q) has a physical meaning only at Q wave vector can be calculated via the relationship... [Pg.164]

Widespread medicinal use of colloidal bismuth subcitrate (CBS) has prompted extensive studies of bismuth compounds involving the citrate anion. Bismuth citrate is essentially insoluble in water, but a dramatic increase in solubility with increasing pH has been exploited as a bio-ready source of soluble bismuth, a material referred to as CBS. Formulation of these solutions is complicated by the variability of the bismuth anion stoichiometry, the presence of potassium and/ or ammonium cations, the susceptibility of bismuth to oxygenation to Bi=0, and the incorporation of water in isolated solids. Consequently, a variety of formulas are classified in the literature as CBS. Solids isolated from various, often ill-defined combinations of bismuth citrate, citric acid, potassium hydroxide, or ammonium hydroxide have been assigned formulas on the basis of elemental analysis data or by determination of water and ammonia content, but are of low significance in the absence of complementary data other than thermal analysis (163), infrared spectroscopy (163), or NMR spectroscopy (164). In this context, the Merck index lists the chemical formula of CBS as KgfNHJaBieOafOHMCeHsCbh in the 11th edition (165), but in the most recent edition provides a less precise name, tripotassium dicitrato bismuthate (166). [Pg.336]

The variation in Pb and Zn contents in relation to the 50% probability line between anomalous and background conditions (calculated by LDF with Pb and Zn as variables) was essentially the same at BMS No. 12, Heath Steele ACD zone and the Caribou deposit, but at Heath Steeie B zone the corresponding 50% probability line was at right angles to that at the other three deposits. Wahl (1978) concluded from these and other data that the Heath Steele B zone was a distal deposit whereas the others were proximal deposits. The major elements also define halos related to proximity to mineralization. [Pg.48]

Our very existence is dependent on a number of metals, the most common of which is iron. Some of the more important ones are described below. As essential elements, the beneficial and adverse effects of these metals have been carefully studied and recommendations developed on daily intake. These recommendations are generally very broad and can vary depending on age - child or adult, young or old - or during pregnancy. The recommended daily intakes quoted below are for adults. These recommendations are actually oral exposure levels with intestinal absorption highly variable and dependent on the metal and other variables. A quick look at a typical cereal box will demonstrate the importance placed on these elements. [Pg.121]


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Elements, essential

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