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Parabolic curves

Using the expanded determinants from Problem 6, write explicit algebraic expressions for the three minimization parameters a, b, and c for a parabolic curve fit. [Pg.79]

Proportional limit the point on the stress-strain curve at which will commence the deviation in the stress-strain relationship from a straight line to a parabolic curve (Figure 30.1). [Pg.915]

Divide any plain surface A, II, C, 1), along a line a-l> into an even number, i mid sufficiently small strips, <1, whom ordinates are li, h2, h3, b)t h5. . . . hn-i, h eonsidering contours bet ween three ordinates as parabolic curves, then for seel ion... [Pg.641]

The left (solid) parabolic curve represents the oxidized state, the right one, the reduced state. Let us assume that the system is initially at the oxidized state (left curve). When the interaction metal-reaction species is small, the electronic coupling between is small and the system may oscillate many times on the left parabolic curve (ox) before it is transferred to the curve on the right (red). On the other hand, if the interaction is strong, the free energy should no longer be represented by the two solid curves in the intermediate region of the reaction coordinate, but rather, by the dashed... [Pg.665]

Figure 6.23 Potential energy description of an electron-transfer reaction. The parabolic curves intersect at the transition state (if)... Figure 6.23 Potential energy description of an electron-transfer reaction. The parabolic curves intersect at the transition state (if)...
The potential energy surfaces on which the electron-transfer process occurs can be represented by simple two-dimensional intersecting parabolic curves (Figure 6.23). These quantitatively relate the rate of electron transfer to the reorganisation energy (A.) and the free-energy changes for the electron-transfer process (AG°) and activation (AG ). [Pg.113]

Fig. 5.1 A schematic projection of the 3n dimensional (per molecule) potential energy surface for intermolecular interaction. Lennard-Jones potential energy is plotted against molecule-molecule separation in one plane, the shifts in the position of the minimum and the curvature of an internal molecular vibration in the other. The heavy upper curve, a, represents the gas-gas pair interaction, the lower heavy curve, p, measures condensation. The lighter parabolic curves show the internal vibration in the dilute gas, the gas dimer, and the condensed phase. For the CH symmetric stretch of methane (3143.7 cm-1) at 300 K, RT corresponds to 8% of the oscillator zpe, and 210% of the LJ well depth for the gas-gas dimer (Van Hook, W. A., Rebelo, L. P. N. and Wolfsberg, M. /. Phys. Chem. A 105, 9284 (2001))... Fig. 5.1 A schematic projection of the 3n dimensional (per molecule) potential energy surface for intermolecular interaction. Lennard-Jones potential energy is plotted against molecule-molecule separation in one plane, the shifts in the position of the minimum and the curvature of an internal molecular vibration in the other. The heavy upper curve, a, represents the gas-gas pair interaction, the lower heavy curve, p, measures condensation. The lighter parabolic curves show the internal vibration in the dilute gas, the gas dimer, and the condensed phase. For the CH symmetric stretch of methane (3143.7 cm-1) at 300 K, RT corresponds to 8% of the oscillator zpe, and 210% of the LJ well depth for the gas-gas dimer (Van Hook, W. A., Rebelo, L. P. N. and Wolfsberg, M. /. Phys. Chem. A 105, 9284 (2001))...
According to observations with metal electrodes in aqueous solution [Amokrane-Badiali, 1992], the interfadal charge versus capacity curve is described for the inverse capacity, 1 /Cm, as a parabolic curve with its maximum near the zero charge the capacity, Cs, is described as a parabolic curve with its maximum near the zero charge. Both of their dependences are shown schematically in Fig. 5-22. Usually, then, the total capacity Ch of the compact layer is represented by a parabolic curve with its maximum near the zero charge (a = 0) of the interface. Figure 5-23 shows the capacity of the compact layer observed for silver and mercury electrodes in aqueous solution as a function of the interfacial charge. [Pg.149]

In the presence of an oxidant, e.g., chlorate or bromate ions, the electrode reaction is transposed into an adsorption coupled regenerative catalytic mechanism. Figure 2.85 depicts the dependence of the azobenzene net peak current with the concentration of the chlorate ions used as an oxidant. Different curves in Fig. 2.85 correspond to different adsorption strength of the redox couple that is controlled by the content of acetonitrile in the aqueous electrolyte. In most of the cases, parabolic curves have been obtained, in agreement with the theoretically predicted effect for the surface catalytic reaction shown in Fig. 2.81. In a medium containing 50% (v/v) acetonitrile (curve 5 in Fig. 2.85) the current dramatically increases, confirming that moderate adsorption provides the best conditions for analytical application. [Pg.119]

The uncertainty in the estimate of (the value of y, at x = 0) is relatively large (s = j x29.48). Figure 8.7 suggests that this is reasonable - any uncertainty in the response will cause the parabolic curve to wiggle , and this wiggle will have a rather severe effect on the intersection of the parabola with the response axis. [Pg.145]

The power versus efficiency characteristics of the endoreversible Carnot heat engine is a parabolic curve. The endoreversible heat engine is a simple model, which considers the external heat-transfer irreversibility between the heat engine and its surrounding heat reservoirs only. [Pg.363]

As shown in Figure 14.5, a plot of the filtrate volume Vf versus time t gives a parabolic curve. [Pg.240]

Fig. 4.5.1. Hardness curve of Mohs standard determined on means from five measurements made by scratch and abrasion methods, and from five measurements by indentation method compared with the parabolic curve y = x3. (After Povarennykh, 1963)... Fig. 4.5.1. Hardness curve of Mohs standard determined on means from five measurements made by scratch and abrasion methods, and from five measurements by indentation method compared with the parabolic curve y = x3. (After Povarennykh, 1963)...
The interpolated curves are given as horizontal lines in Figure 3, and the Kc/Re values at constant time are given by A. The vertical parabolic curves result at their lowest end in the lime o Kc/Re values, given by . [Pg.105]

If we plot log k as a function of-AGo we obtain a parabolic curve. In particular the part where Ea increases for -AG°>>. is called the inverted region [36]. [Pg.16]

Any process takes a certain amount of time and the length of the residence time often dictates the occasions when particular equipment or technology can be used. On the other hand, in almost all chemical unit processes the driving forces vary from time to time, and therefore time has the nature of non-equivalence, i.e., an equal time interval yields different, even greatly different, results for the early and later stages of a process. The result mentioned here means the processing amount accomplished, such as the increments of reaction conversion, absorption efficiency, moisture removal etc. Normally, these parameters vary as parabolic curves with time. Because of the nature of the non-equivalence of time, in addition to the mean residence time, the residence time distribution (RTD) affects the performance of equipment, and thus receives common attention. [Pg.67]

Investigation of the velocity profiles obtained for the first case (crossection (x, y = 70 nm)) indicates a strong decrease of the maximum fluid velocity with increasing electrolyte concentration (see Figure 4). Furthermore, a transition of the velocity curves from a parabolic curve classically obtained from the Navier-Stokes problem (i.e., c = 0 mol/m3) to a very flattend curve for high electrolyte concentration (c = 1000 mol/m3) can be seen. [Pg.295]

For t0, this double correlation can be expressed by a parabolic curve as... [Pg.106]

Figure 9.7. A total power radiometer with a bolometer [a square-law device indicated by the parabolic curve] feeding a DC amphfier. This design will have too much 1// noise to be useful. Figure 9.7. A total power radiometer with a bolometer [a square-law device indicated by the parabolic curve] feeding a DC amphfier. This design will have too much 1// noise to be useful.
NaHA is a proton-donating salt, in which the concentration of [H+] [OH] and HA- is the predominant species. Therefore, the fractional composition of IIA is located at the upper portion of the ascending parabolic curve of HA- and the concentration of H+ is much greater than Ka2. If Ca [H+], Equation (2.112) becomes ... [Pg.95]


See other pages where Parabolic curves is mentioned: [Pg.193]    [Pg.605]    [Pg.13]    [Pg.79]    [Pg.63]    [Pg.108]    [Pg.30]    [Pg.138]    [Pg.399]    [Pg.550]    [Pg.20]    [Pg.54]    [Pg.130]    [Pg.345]    [Pg.128]    [Pg.58]    [Pg.21]    [Pg.254]    [Pg.258]    [Pg.107]    [Pg.40]    [Pg.742]    [Pg.424]    [Pg.241]    [Pg.206]    [Pg.206]    [Pg.288]    [Pg.88]    [Pg.94]    [Pg.164]   
See also in sourсe #XX -- [ Pg.2 , Pg.206 ]

See also in sourсe #XX -- [ Pg.2 , Pg.206 ]




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Parabolic

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