Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Point A:-valued

Once the stoichiometry of the complex has been established, the stability constant(s) can be calculated, provided the data yields a curve showing some dissociation in the neighborhood of the stoichiometric point (curve B in Figure 22-12). Briefly, for any data point in the region of curvature, complex formation did not proceed to completion, as evidenced from the difference between the measured curve and the "theoretical" one. Here there is obviously an equilibrium between metal ion, ligand and complex, and from each data point a value of the stability constant can be calculated. [Pg.360]

The value of the charge density at a bond critical point can be used to define a bond order (Bader et al. 1983 Cremer and Kraka 1984). The molecular graphs for ethane, ethylene, and acetylene are shown in Fig. 2.8. In each case the unique pair of trajectories associated with a single (3, — 1) critical point is found to link the carbon nuclei to one another. Multiple bonds do not appear as such in the topology of the charge density. Instead, one finds that the extent of charge accumulation between the nuclei increases with the assumed number of electron pair bonds and this increase is faithfully monitored by the value of p at the bond critical point, a value labelled p, . For carbon-carbon bonds, one can define a bond order n in terms of the values of Ph using a relationship of the form... [Pg.75]

In some applications the gas flows through relatively thin capillaries after leaving the saturator. With increasing gas velocity, the pressure in the saturator rises significantly and may reach several hundred mbar above the atmospheric pressure. If at this point a value of 1.013 bar is inserted into the equation, instead of the correct pressure in the saturator, (Equation 16-11), an error rate of more than lot s will result. [Pg.162]

Temperature is a measure of the hotness of matter determined in relation to fixed hotness points of melting ice and boiling water. Two scales are universally accepted, the Celsius (or Centigrade) scale which is based on a scale of 100 divisions and the Fahrenheit scale of 180 divisions between these two hotness points. Because Fahrenheit had recorded temperatures lower than that of melting ice he gave that hotness point a value of 32 degrees. Converting from one scale to the other ... [Pg.487]

A value of R = 1.0 means that the curve passes through every data point. A value of R = 0.0 means that the regression model does not describe the data any better than a horizontal line (i.e., the average y) passing through the data points. [Pg.144]

Outside the two-phase region, ELIPS yields a value of 0 for E/F on the R-phase side and 1 for E/F on the E-phase side. Con-, vergence to these values again requires about eight or fewer iterations, except near the plait-point region where convergence is somewhat slower. [Pg.127]

The problem of explosion of a vapor cloud is not only that it is potentially very destructive but also that it may occur some distance from the point of vapor release and may thus threaten a considerable area. If the explosion occurs in an unconfined vapor cloud, the energy in the blast wave is generally only a small fraction of the energy theoretically available from the combustion of all the material that constitutes the cloud. The ratio of the actual energy released to that theoretically available from the heat of combustion is referred to as the explosion efficiency. Explosion efficiencies are typically in the range of 1 to 10 percent. A value of 3 percent is often assumed. [Pg.258]

Unlike the pressure where p = 0 has physical meaning, the zero of free energy is arbitrary, so, instead of the ideal gas volume, we can use as a reference the molar volume of the real fluid at its critical point. A reduced Helmlioltz free energy in tenns of the reduced variables and F can be obtained by replacing a and b by their values m tenns of the critical constants... [Pg.619]

Consequently, when D /Dj exceeds the critical value, close to the bifurcation one expects to see the appearance of chemical patterns with characteristic lengtli i= In / k. Beyond the bifurcation point a band of wave numbers is unstable and the nature of the pattern selected (spots, stripes, etc.) depends on the nonlinearity and requires a more detailed analysis. Chemical Turing patterns were observed in the chlorite-iodide-malonic acid (CIMA) system in a gel reactor [M, 59 and 60]. Figure C3.6.12(a) shows an experimental CIMA Turing spot pattern [59]. [Pg.3069]

A linear dependence approximately describes the results in a range of extraction times between 1 ps and 50 ps, and this extrapolates to a value of Ws not far from that observed for the 100 ps extractions. However, for the simulations with extraction times, tg > 50 ps, the work decreases more rapidly with l/tg, which indicates that the 100 ps extractions still have a significant frictional contribution. As additional evidence for this, we cite the statistical error in the set of extractions from different starting points (Fig. 2). As was shown by one of us in the context of free energy calculations[12], and more recently again by others specifically for the extraction process [1], the statistical error in the work and the frictional component of the work, Wp are related. For a simple system obeying the Fokker-Planck equation, both friction and mean square deviation are proportional to the rate, and... [Pg.144]

Assign A value of 1 or 0 to each grid point to identify points that are or are not accessible to mobile ions, respectively. [Pg.184]

This treatment of reaction at the limit of bulk diffusion control is essentially the same as that presented by HugoC 69j. It is attractive computationally, since only a single two-point boundary value problem must be solved, namely that posed by equations (11.15) and conditions (11.16). This must be re-solved each time the size of the pellet is changed, since the pellet radius a appears in the boundary conditions. However, the initial value problem for equations (11.12) need be solved only once as a preliminary to solving (11.15) and (11.16) for any number of different pellet sizes. [Pg.117]

Corrected Melting-points. In all the above determinations of melting-points, the values obtained are described as uncorrected, since no allowance has been made for the fact that the column of mercury in the thermometer is at a lower temperature than that in the bulb. For most purposes it is sufficient to record this uncorrected value, which is usually only slightly lower than the corrected value. [Pg.6]


See other pages where Point A:-valued is mentioned: [Pg.116]    [Pg.349]    [Pg.333]    [Pg.64]    [Pg.173]    [Pg.1117]    [Pg.108]    [Pg.86]    [Pg.333]    [Pg.248]    [Pg.298]    [Pg.260]    [Pg.149]    [Pg.805]    [Pg.116]    [Pg.349]    [Pg.333]    [Pg.64]    [Pg.173]    [Pg.1117]    [Pg.108]    [Pg.86]    [Pg.333]    [Pg.248]    [Pg.298]    [Pg.260]    [Pg.149]    [Pg.805]    [Pg.77]    [Pg.170]    [Pg.830]    [Pg.278]    [Pg.17]    [Pg.566]    [Pg.665]    [Pg.885]    [Pg.1334]    [Pg.1934]    [Pg.3062]    [Pg.28]    [Pg.325]    [Pg.116]    [Pg.156]    [Pg.170]    [Pg.208]    [Pg.257]    [Pg.278]    [Pg.351]    [Pg.621]    [Pg.717]   
See also in sourсe #XX -- [ Pg.2 ]




SEARCH



A values

Point valued

© 2024 chempedia.info