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Derived quantities, dimensional

Primary and Secondary (Derived) Quantities Dimensional Constants A distinction is made between primary or base quantities and secondary quantities derived from them. The base quantities are based on standards and are quantified by comparison with them. The secondary quantities are derived from the primary ones according to physical laws, e.g. velocity = length/time. All secondary measuring units must be coherent with the base units, e.g. the measuring unit of velocity must not be miles/hr or km/hr but m/s ... [Pg.62]

Another class of derived quantities is represented by the dimensional coefficients in the transfer equations of momentum, mass and heat. These are so-called definition quantities , established by the respective physical equations and are only determinable via measurement of their constituents. [Pg.63]

The quantity k is related to the intensity of the turbulent fluctuations in the three directions, k = 0.5 u u. Equation 41 is derived from the Navier-Stokes equations and relates the rate of change of k to the advective transport by the mean motion, turbulent transport by diffusion, generation by interaction of turbulent stresses and mean velocity gradients, and destmction by the dissipation S. One-equation models retain an algebraic length scale, which is dependent only on local parameters. The Kohnogorov-Prandtl model (21) is a one-dimensional model in which the eddy viscosity is given by... [Pg.102]

Chapter 8 presented the last of the computational approaches that I find widely useful in the numerical simulation of environmental properties. The routines of Chapter 8 can be applied to systems of several interacting species in a one-dimensional chain of identical reservoirs, whereas the routines of Chapter 7 are a somewhat more efficient approach to that chain of identical reservoirs that can be used when there is only one species to be considered. Chapter 7 also presented subroutines applicable to a generally useful but simple climate model, an energy balance climate model with seasonal change in temperature. Chapter 6 described the peculiar features of equations for changes in isotope ratios that arise because isotope ratios are ratios and not conserved quantities. Calculations of isotope ratios can be based directly on calculations of concentration, with essentially the same sources and sinks, provided that extra terms are included in the equations for rates of change of isotope ratios. These extra terms were derived in Chapter 6. [Pg.180]

The major components are series of homologous trimers, tetramers, and pentamers of the three acids 44-46, along with smaller quantities of dimers, hexamers, and heptamers. Furthermore, the secretion contains several isomers of each oligomer, furnishing a combinatorial library of several hundred macro-cyclic polyamines [51, 52]. Using repeated preparative HPLC fractionation, the most abundant trimeric, tetrameric and pentameric earliest-eluting compounds were isolated. One and two-dimensional H NMR spectroscopic analyses showed that these molecules were the symmetric macrocyclic lactones 48, 49, and 50 (m, n, o, p, q=7) derived from three, four or five units, respectively, of acid 46. Moreover, using preparative HPLC and NMR methods, various amide isomers, such as 53,54, and 55 (Fig. 9) were also isolated and characterized [51,52]. [Pg.192]

The study of the basaltic dykes in evaporites demonstrates that dissolution and precipitation of phosphate minerals is a key process for the control of REE mobility and REE fractionation. In the present case, all REE found in secondary apatite in the basalt and in the salt are derived from the dissolution of primary magmatic apatite during basalt corrosion. This loss of REE from the basalt to the salt was not sufficient to lower significantly the REE concentrations of the basalt and it could only be detected by the analysis of the salt. The absolute quantity of REE transferred from the basalt into the salt, however, cannot be quantified because we have no three-dimensional control on the REE concentrations around the basalt apophy sis. [Pg.140]

The statistical thermodynamic approach to the derivation of an adsorption isotherm goes as follows. First, suitable partition functions describing the bulk and surface phases are devised. The bulk phase is usually assumed to be that of an ideal gas. From the surface phase, the equation of state of the two-dimensional matter may be determined if desired, although this quantity ceases to be essential. The relationships just given are used to evaluate the chemical potential of the adsorbate in both the bulk and the surface. Equating the surface and bulk chemical potentials provides the equilibrium isotherm. [Pg.420]

Equation (12.53) gives the desired evaluation of the general thermodynamic derivative V in a system of/degrees of freedom, expressed in terms of known geometrical quantities. As in the two-dimensional case, other expressions for V would be possible in other special choices of basis. Equation (12.53) is suitable for machine computation in multicomponent thermodynamic systems of arbitrary complexity. [Pg.407]

The object of a crystal-structure determination is to ascertain the position of all of the atoms in the unit cell, or translational building block, of a presumed completely ordered three-dimensional structure. In some cases, additional quantities of physical interest, e.g.. the amplitudes of thermal motion, may also be derived from the experiment. The processes involved in such crystal-structure determinations may he divided conveniently into (I) collection of the data. (2) solution of the phase relations among the scattered x-rays (phase problem)—determination of a correct trial structure, and (3) refinement of this structure. [Pg.454]

For the function we again obtain equation (9) with the source S determined by the time-bounded quantity VnHn and its derivatives and velocity. This implies that rapid (exponential) growth of the two-dimensional field component is impossible. [Pg.102]

The identification of quantity with unlimited extension thus allows for a derivation of the species in quantity. The main divisions in the category of quantity have already been derived. Continuous quantity and measurable quantity are convertible—and they arise from the limiting of extension by form-m. Discrete quantity and numerable quantity are likewise convertible—and they arise from the limiting of form matter composites by forms-c. And because number, owing to the elimination of Xoyog, is the only species under numerable quantity, we can suppose that numbers (of F s) just are limited pluralities of a certain sort. The divisions among the types of continuous quantity, then, flow from the dimensionality of extension itself. Body is limited measurable quantity in three dimensions surface, limited measurable quantity in two dimensions and line, limited measurable quantity in one dimension.9... [Pg.128]

An equation governing this quantity was derived in Chapter 2. If the mean flow is two-dimensional, this equation is ... [Pg.239]


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Derived quantities

Derived quantities, dimensional analysis

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