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Intermediate values

Since they all necessitate a knowledge of the value of r, and of both r and either directly or indirectly, all as a function of p p°, these data are given in tabular form for reference (Table 3.2). If required, intermediate values of t may be obtained to sufficient accuracy by graphical interpolation, and the corresponding values of r can be calculated with the Kelvin formula. The values of r refer to the most commonly used model, the cylindrical pore, so that r " = r + t. The values of t are derived from the standard nitrogen isotherm for hydroxylated silica and though the values do differ... [Pg.135]

Using equation 10.25, the value of can be determined in one of two ways. The simplest approach is to prepare three solutions, each of which contains the same amount, C, of indicator. The pH of one solution is made acidic enough that [HIn] [In-]. The absorbance of this solution gives Anin- The value of Ain is determined by adjusting the pH of the second solution such that [In-] [HIn]. Finally, the pH of the third solution is adjusted to an intermediate value, and the pH and absorbance, A, are recorded. The value of can then be calculated by making appropriate substitutions into equation 10.25. [Pg.408]

At any p, very small and very large values of n contribute a lower weight fraction to the mixture than do intermediate values of n. This arises because of the product nN in Eq. (5.29) is large for monomers, in which case n... [Pg.295]

For conditions of intermediate solvent goodness, a shows a dependence on M which is intermediate between the limits described in items (1) and (2) with the corresponding intermediate values for the Mark-Houwink a coefficient. [Pg.620]

The value for the heat of fusion of PPS, extrapolated to a hypothetical 100% crystalline state, is not agreed upon in the literature. Reported values range from approximately 80 J/g (19 cal/g) (36,96,101) to 146 J/g (35 cal/g) (102), with one intermediate value of 105 J/g (25 cal/g) (20). The lower value, 80 J/g, was originally measured by thermal analysis and then correlated with a measure of crystallinity deterrnined by x-ray diffraction (36). The value of 146 J/g was deterrnined independendy on uniaxiaHy oriented PPS film samples by thermal analysis, density measurement via density-gradient column, and the use of a calculated density for 100% crystalline PPS to arrive at a heat of fusion for 100% crystalline PPS (102). The value of 105 J/g was obtained by measuring the heats of fusion of weU-characterized linear oligomers of PPS and extrapolation to infinite molecular weight. [Pg.446]

By way of comparison, for natural grass playing fields in late autumn ranges from about 75 for wet fields to 280 for fro2en turf (8). The intermediate values observed depend on soil type, moisture, condition, and other variables. [Pg.534]

It is evident, by comparing equations 2 and 3, that tensile strength in the pendular state is about one-tbhd that in the capillary state. Intermediate Hquid contents in the funicular state (Fig. lb) yield intermediate values that can be approximated as foUows ... [Pg.110]

The values for a single property of two compounds, A and B, are useless unless these values are compared at equal temperature or pressure. Then a deviation from some intermediate value can be determined. If this intermediate value is chosen to be the value of one particular substance, ie. A, the reference substance, both A and B can then be expressed as functions of the reference substance. One very simplistic example is specific gravity where the density of a compound is expressed as the actual density divided by the density of water at 4°C and water is the reference substance. [Pg.242]

For normal velocity distribution in straight circular pipes at locations preceded by runs of at least 50 diameters without pipe fittings or other obstructions, the graph in Fig. 10-7 shows the ratio of mean velocity V to velocity at the center plotted against the Reynolds number, where D = inside pipe diameter, p = flmd density, and [L = fluid viscosity, all in consistent units. Mean velocity is readily determined from this graph and a pitot reading at the center of the pipe if the quantity Du p/ I is less than 2000 or greater than 5000. The method is unreliable at intermediate values of the Reynolds number. [Pg.888]

To integrate Eq. (11-3), and AT must be known as functions of Q. For some problems, varies strongly and nonlinearly throughout the exchanger. In these cases, it is necessary to evaluate and AT at several intermediate values and numerically or graphically integrate. For many practical cases, it is possible to calculate a constant mean overall coefficient from Eq. (11-2) and define a corresponding mean value of AT,n, such that... [Pg.1034]

In either equation, /c is given by Eq. (16-84) for parallel pore and surface diffusion or by Eq. (16-85) for a bidispersed particle. For nearly linear isotherms (0.7 < R < 1.5), the same linear addition of resistance can be used as a good approximation to predict the adsorption behavior of packed beds, since solutions for all mechanisms are nearly identical. With a highly favorable isotherm (R 0), however, the rate at each point is controlled by the resistance that is locally greater, and the principle of additivity of resistances breaks down. For approximate calculations with intermediate values of R, an overall transport parameter for use with the LDF approximation can be calculated from the following relationship for sohd diffusion and film resistance in series... [Pg.1516]

The pumped-discharge case is generally more difficult to solve because of the uncertainty in deahng with negative numerical results. As a final answer, a negative value could indicate that the pump has completely emptied the tank however, as an intermediate value, it could mean that it is not a true solution. A simple check is to try a different initial estimate and see if the intermediate negative results disappear. [Pg.2337]

The intermediate values for M are derived from the squared relationship that is analogous to that of the relative cost/difficulty trend exhibited by manufacturing processes and their tolerance capability (see Figure 2.12). [Pg.52]

For mopermalloy toroids, the method for estimating the needed eore size is done by ealeulating an intermediate value of the energy being stored in the eore, using Equation 3.33 ... [Pg.46]

The term r Vf in Equation (3.71) can be interpreted as a reduced fiber-volume fraction. The word reduced is used because q 1. Moreover, it is apparent from Equation (3.72) that r is affected by the constituent material properties as well as by the reinforcement geometry factor To further assist in gaining appreciation of the Halpin-Tsai equations, the basic equation. Equation (3.71), is plotted in Figure 3-39 as a function of qV,. Curves with intermediate values of can be quickly generated. Note that all curves approach infinity as qVf approaches one. Obviously, practical values of qV, are less than about. 6, but most curves are shown in Figure 3-39 for values up to about. 9. Such master curves for various vaiues of can be used in design of composite materiais. [Pg.157]

SnO and hydrous tin(II) oxide are amphoteric, dissolving readily in aqueous acids to give Sn" or its complexes, and in alkalis to give the pyramidal Sn(OH)3 at intermediate values of pH, condensed basic oxide-hydroxide species form, e.g. [(OH)2SnOSn(OH)2] and [Sn3(OH)4] +, etc. Analytically, the hydrous oxide frequently has a composition close to 3Sn0.H20 and an X-ray study shows it to... [Pg.383]

Many compounds, of which [NiBr2(PEtPh2)2] mentioned above is one, exist in solution as mixtures of isomers giving rise to intermediate values of (0-3.2 BM). Such behaviour, previously regarded as anomalous is due to one of three possible types of equilibria ... [Pg.1160]

Planar-octahedral equilibria. Dissolution of planar Ni compounds in coordinating solvents such as water or pyridine frequently leads to the formation of octahedral complexes by the coordination of 2 solvent molecules. This can, on occasions, lead to solutions in which the Ni has an intermediate value of jie indicating the presence of comparable amounts of planar and octahedral molecules varying with temperature and concentration more commonly the conversion is complete and octahedral solvates can be crystallized out. Well-known examples of this behaviour are provided by the complexes [Ni(L-L)2X2] (L-L = substituted ethylenediamine, X = variety of anions) generally known by the name of their discoverer I. Lifschitz. Some of these Lifschitz salts are yellow, diamagnetic and planar, [Ni(L-L)2]X2, others are blue, paramagnetic, and octahedral, [Ni(L-L)2X2] or... [Pg.1160]

More than 60 percent of natural gas physically consumed in the course of a year is nevertheless attributable to purchases at lower, interruptible prices by industrial boilcr-fucl users and electrical generators that are capable of substituting natural gas in off-peak months, when gas is available at prices competitive with those of black fuels (coal and heavy fuel oil). In addition to these relatively low-value, pricc-scnsitivc industrial gas uses is a wide range of intermediate-value demand categories for natural gas, such as in process and feedstock use. [Pg.823]

Note Interpolate for intermediate values. The total surface area does not include the area of ground plates but does include roof areas less than 30 feet above grade. [Pg.476]

Z3 correspond to the maximum and minimum values of cos ere P, = power ratio (i.e., the percentage of power passing W. Solving the abscissa value, 2tt L/C for f yields the frequency at which maximum, minimum, and 0 values of cos W occur. The cos W curve may now he constructed. Intermediate values of cos W may he approximated from this curve to construct the power ratio curve, shown in Figures 13-21A and 13-21B. [Pg.600]

Internal stress of copper deposits may vary between —3.4MN/m (compressive) and -1- l(X)MN/m (tensile). In general, tensile stress is considerably lower in deposits from the sulphate bath than in those from cyanide solutions " , while pyrophosphate copper deposits give intermediate values. In cyanide solutions, tensile stress increases with metal concentration and temperature decreases if the free cyanide concentration is raised. P.r. current significantly lowers tensile stress. With some exceptions, inorganic impurities tend to increase tensile stress . Thiocyanate may produce compressive stress in cyanide baths . [Pg.521]

A increases from that point on. From the perspective of computation theory taken in his paper, Langton argues that it is the set of intermediate values of A that are most important. [Pg.105]

Choosing to describe their rule in terms of a spread of a disease, Gerhardt and Schuster interpret a as follows. Cells whose value a = 0 are labeled as healthy cells cells with value a = N are labeled as ill cells cells with intermediate values 1 < a < N are called infected. The temporal evolution of the system, parameterized by constants p,/(, pj and u (see below), is then defined in terms of these three different infection states. [Pg.423]

In general, if K is a very small number, the equilibrium mixture will contain mostly unreacted starting materials for all practical purposes, the forward reaction does not go. Conversely, a large K implies a reaction that, at least in principle, is feasible products should be formed in high yield. Frequently, K has an intermediate value, in which case you must make quantitative calculations concerning the direction or extent of reaction. [Pg.333]


See other pages where Intermediate values is mentioned: [Pg.327]    [Pg.727]    [Pg.971]    [Pg.15]    [Pg.295]    [Pg.49]    [Pg.355]    [Pg.50]    [Pg.11]    [Pg.16]    [Pg.731]    [Pg.874]    [Pg.13]    [Pg.56]    [Pg.315]    [Pg.618]    [Pg.524]    [Pg.86]    [Pg.91]    [Pg.675]    [Pg.30]    [Pg.41]    [Pg.300]    [Pg.967]    [Pg.100]    [Pg.252]   
See also in sourсe #XX -- [ Pg.286 ]




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