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F-Table

The F statistic describes the distribution of the ratios of variances of two sets of samples. It requires three table labels the probability level and the two degrees of freedom. Since the F distribution requires a three-dimensional table which is effectively unknown, the F tables are presented as large sets of two-dimensional tables. The F distribution in Table 2.29 has the different numbers of degrees of freedom for the denominator variance placed along the vertical axis, while in each table the two horizontal axes represent the numerator degrees of freedom and the probability level. Only two probability levels are given in Table 2.29 the upper 5% points (F0 95) and the upper 1% points (Fq 99). More extensive tables of statistics will list additional probability levels, and they should be consulted when needed. [Pg.204]

The precision of measurement does not appear to be very high. Confidence levels in the precision may be made by use of "Student f" Tables. [Pg.362]

To compare the results of the correlation presented in this article and an exact numerical solution, let us consider the case where air with a wet-bulb temperature of 70°F is used to cool water from 120°F to 80°F. Table 1 summarizes the results for different air-to-water flow rate ratios. [Pg.159]

Of the typical ergot alkaloids, six pairs f table, p. 526) are now known. The first five pairs are more complex in structure than the sixth pair, ergometrine and eigometrinine. [Pg.534]

SAE numbers have been established by the Society of Automotive Engineers to specify ranges of SUS viscosities of oils at SAE test temperatures. Winter numbers (5W, low, 20W) are determined by tests at 0°F. Summer numbers (20W, SOW, etc.) designate the SUS range at 210°F. Table 40.1 is a chart of the temperature ranges. [Pg.599]

When a water-based fluid makes contact with a flame or a hot surface its water component evaporates and forms a steam blanket that displaces oxygen from around the hot area, and this obviates the risk of fire. Water-based products all contain at least 35% water. Because water can be lost by evaporation, they should not be subjected to operating temperatures above about 60°C (140°F). Table 52.8 shows a comparison of oil and FR fluids. [Pg.864]

Figure 3. Oxidation of (1 i.)-l,2,4/3,5-cyclohexanepentol (curve A minutes Curve C hours) and of (+)-quercitol (curve B minutes curve D hours) with sodium metaperiodate (c.f. Table I). Figure 3. Oxidation of (1 i.)-l,2,4/3,5-cyclohexanepentol (curve A minutes Curve C hours) and of (+)-quercitol (curve B minutes curve D hours) with sodium metaperiodate (c.f. Table I).
This value is identified in F tables for the corresponding dfc and dfs. For example, for the data in Figure 11.13, F = 7.26 for df=6, 10. To be significant at the 95% level of confidence (5% chance that this F actually is not significant), the value of F for df = 6, 10 needs to be > 4.06. In this case, since F is greater than this value there is statistical validation for usage of the most complex model. The data should then be fit to a four-parameter logistic function to yield a dose-response curve. [Pg.241]

A similar dependence of the stereoselectivity on the solvent and reaction temperature was found with the x-oxo amides 9 derived from phenylglyoxylic acid (R = C6H5) and 2-oxopropanoic acid (R = CH3) with amine F (Table 23)15. Thus, the highest selectivity was observed under chelation-controlled conditions in the presence of the Lewis acid titanium(IV) chloride. [Pg.102]

The critical value F is taken from an F-table or is approximated (cf. Section 5.1.3) if... [Pg.70]

For identification, an excerpt from the F-table for p - 0.05 is given as follows ... [Pg.72]

The complete elimination of functional groups is often an undesirable side reaction in organic synthesis, but on the other hand it is a possibility for the recycling of environmentally harmful compounds, for example phenols and haloarenes such as polychlorinated dibenzodioxins (PCDDs or dioxins ). For example, aryl chlorides can be effectively dechlorinated with Pd(0) NPs in tetra-butylammonium salts with almost quantitative conversions also after 19 runs (entry H, Table 1.4) [96]. On the other hand, a C-0 bond cleavage reaction also seems suitable for the fragmentation of sugar-based biomass such as cellulose or cello-biose in that way, sugar monomers and bioalcohol can be derived from renewable resources (entry F, Table 1.4) [164]. [Pg.20]

One way to solve the problem of unphysically short atomic distances is to project onto the Rpm subspace only those grid points included in a selected strip (gray area), with width of a (cos a + sin a) in the A per subspace. The slope of RPai shown in Fig. 1 is 0.618..., an irrational number related to the golden mean [( /5 + l)/2 = 1.618...]. As a result, the projected ID structure contains two segments (denoted as L and S), and their distribution follows a ID quasiperiodic Fibonacci sequence [2] (c.f. Table 1). From another viewpoint, the ID quasiperiodic structure on the par subspace can be conversely decomposed into periodic components (square lattice) in a (higher) 2D space. The same strip/projection scheme holds for icosahedral QCs, which are truly 3D objects but apparently need a more complex and abstract 6D... [Pg.14]

The chemical reactivity of 1,3,4-thiadiazole 1 was predicted using DFT by calculating the net atomic charges and the Fukui functions /+,/ , and f° (Table 2). [Pg.570]

F statistic A statistic which is used as a measure of the goodness of fit of a data set to a correlation equation. The larger the value of F, the better the fit. Confidence levels can be assigned by comparing the F value calculated with the values in an F table for the Np and DF values of the data set. [Pg.730]

The value of the overall oxygen transfer coefficient, KLa = KLC>2, is central for the determination of the rate of oxygen transfer, F. Table 4.7 summarizes a number of empirical expressions proposed for the determination of K,a in gravity sewers (Jensen, 1994). [Pg.88]

The estimated uncertainties in the average values bb/ aa and bbAaa °f Tables V and VI are respectively 0-02 and 0.01 (resulting from both experimental errors and deviations from the theorem of corresponding states). This unavoidably leads to rather high inaccuracies in 8 and p (20% in the case of CH4-Kr considered above). [Pg.135]

Landini et al. (1974, 1975) have studied nucleophilic substitutions in n-octyl derivatives in two-phase systems (substrate-water) catalysed by a mixture of dicyclohexyl-18-crown-6 isomers ([20] + [21]). They observed the following order of nucleophilicity I- > CN-, Br > Cl- > F (Table 32), which is... [Pg.329]

The optical properties of organic dyes (Fig. ld-f, Table 1) are controlled by the nature of the electronic transition(s) involved [4], The emission occurs either from an electronic state delocalized over the whole chromophore (the corresponding fluorophores are termed here as resonant or mesomeric dyes) or from a charge transfer (CT) state formed via intramolecular charge transfer (ICT) from the initially excited electronic state (the corresponding fluorophores are referred to as CT dyes) [4], Bioanalytically relevant fluorophores like fluoresceins, rhodamines, most 4,4 -difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPY dyes), and cyanines (symmetric... [Pg.12]


See other pages where F-Table is mentioned: [Pg.95]    [Pg.726]    [Pg.727]    [Pg.727]    [Pg.728]    [Pg.329]    [Pg.44]    [Pg.1151]    [Pg.127]    [Pg.127]    [Pg.1001]    [Pg.353]    [Pg.116]    [Pg.122]    [Pg.239]    [Pg.283]    [Pg.284]    [Pg.286]    [Pg.148]    [Pg.72]    [Pg.26]    [Pg.181]    [Pg.133]    [Pg.153]    [Pg.251]    [Pg.424]    [Pg.37]    [Pg.663]    [Pg.73]    [Pg.749]   
See also in sourсe #XX -- [ Pg.94 ]




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