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Conventional equations

Though the applicability of Eq. (2.39) is restricted, it has certain advantages over the conventional equation of orientational diffusion proposed by Debye [1]... [Pg.70]

Student drawings and descriptions of their conceptions of structures and processes at the molecular level often reveal misconceptions not detectable in conventional equation-writing questions (p. 155). [Pg.176]

However, it mnst be noted that using this convention, equations for similar phenomena containing current densities mnst always be written in two different ways for anodic currents with the symbol i and for cathodic cnrrents with the symbol 111. For this reason, a mixed system is nsed in the following chapters All cnrrent densities (anodic as well as cathodic) are regarded as positive and denoted by the same symbol, i. In this way the same eqnations containing cnrrent densities can be used for all types of reactions. For the ion flnxes near the snrface of electrodes, the aforementioned signs are preserved (see Chapter 4). [Pg.21]

Equations (6.9) and (6.10), which contain the rate constants, the electrode potential, and the concentrations, are equivalent to Eqs. (6.12) and (6.13), which contain the exchange CD and the electrode s polarization. But in the second set of equations the concentrations do not appear explicitly they enter the equations through the values of exchange CD and equilibrium potential. By convention, equations of the former type will be called kinetic equations, and those of the latter type will be called polarization equations. [Pg.86]

The Z values are calculated using the conventional equations at the pH of the experimental data (i.e., the system pH). The total Z value in water is then separated into its ionic and non-ionic contributions, i.e., fractions of 1/(1+ 1) and 1/(1 + 1). The Z value for the non-ionic form in water is assumed to apply at all pHs i.e., including the environmental pH, but an additional and possibly different ionic Z value in water is deduced at the environmental pH using I calculated at that pH. The total Z values in water are then calculated. Z values in other media are unaffected. [Pg.21]

In general, with the different sign conventions, equations involving stress components have opposite signs in the two conventions. On substituting the appropriate form of Newton s law of viscosity, the sign difference cancels giving identical equations for the velocity profile. [Pg.42]

The authors realised that their rate-constant papp is composite and they assumed that it is given by the conventional Equation (60) in terms of kp+ and p, obviously ignoring... [Pg.570]

Because reinforcing is determined using conventional equations, the details of this procedure are ommitted for brevity. [Pg.97]

The conventional equation of transition state theory is expressed as Eq. (2.119)... [Pg.56]

It was found that conventional equation can be applied for description of the process. The process is the first order with respect to monomer and the order with respect to initiator is 0.25. The energy of activation was estimated at 43 kJ/mol. Moreover, it was found that without initiator, photopolymerization also occurs when the system is illuminated by UV light. [Pg.112]

The proper dose of ketoprofen for an optimized zero-order model to obtain the desired drug level pattern to remain in the therapeutic range for 12 h (twice-a-day formulation) was estimated from drug pharmacokinetic parameters [6] by conventional equations [3] on the basis of a one-compartment open model and was found to be 1 lOmg. [Pg.73]

The integration constant in this expression is easily evaluated if we define the potential in the solution at x = oo to be zero. At the same limit, dip/dx also equals zero. In view of these conventions, Equation (53) becomes... [Pg.516]

M. T. Bowser, G. M. Bebault, X. Peng, and D. D. Y. Chen, Redefining the Separation Factor Pathway to a Unified Separation Science, Electrophoresis 1997,18, 2928. The conventional equation is resolution = ( )(i + J, where ct is relative retention, k 2 is the capacity factor for the more retained component, and k w is the average capacity factor for the two components. This expression is equivalent to (-y — 1) for closely spaced peaks for which... [Pg.680]

The Gibbs convention (Equation 17) states that we compare the real system with a fictitious one having the same total volume and total numbers of moles of all constituents as the real system. Under this convention the total moles of individual components 1 and 2 will differ between the real and the fictitious systems, but because the total of all moles of both components is the same, the surface excesses of each must sum to zero, and this is the meaning of Equation 20. [Pg.14]

This equation describes the fluctuational decrease of particle decay rate when t —> oo in the case of mobile traps. Although in equation (5.2.45) the exponent is the linear function of time, as in the conventional expression (5.2.41) and (5.2.45) however, describes a slower particle decay rate than that predicted by the conventional equation due to the small value of the parameter... [Pg.286]

In Quantum Chemistry, equation systems arise primarily from optimization problems. For simplicity, let us call equations of the type f(x) = 0 conventional equation systems, while those of the type f(x) = v x) are called quasi-secular equations. As we shall see shortly, the former arise from optimization problems with no constrains on the parameters. The quasi-secular equation is obtained when the optimization is done on a subset of the parameter space. Let us assume that some differentiable function Q(x) is to be minimized. We then define the following functions of x ... [Pg.31]

Conventional equation systems and quasi-secular equations are usually interrelated, not only because similar techniques can be used to solve them, but as we have seen, also because an underlying common problem may have been formulated either way. [Pg.32]

These two equations are the conventional equations of ozone and atomic oxygen in an oxygen atmosphere where other constituents play no chemical role. [Pg.66]

The activity of soluble and immobilized invertase was determined by varying the temperature of the standard test within a range of 30-60°C ( 30, 35, 40, 45, 50, 55, and 60°C). A blank was prepared under the same conditions for each temperature employed. The activation energy (E/ kj/ mol) was determined by the Arrhenius method, and the thermodynamic parameters were calculated by conventional equations (Eqs. 3-5) (12). The stability of both forms of invertase (aqueous invertase solution [diluted 1 5000, v/v] or an aqueous suspension of Dowex/invertase (100 mg powder/mL]) was evaluated by maintaining the enzyme solution or suspension for 12 min in acetate buffer (0.010 M, pH 5.5) at each... [Pg.147]

The mean square error in the concentration estimate can be computed just as in PCR, although the value of cin will differ. It is also possible to provide a number of equivalent equations for this error using t and q which are left to the reader. In the case of the concentration estimates, it is usual to adjust the sum of squares according to the number of PLS components, because this number is often similar in magnitude to the number of objects in the dataset for example, there are 25 spectra in case study 1, but we might want to look at the error when ten PLS components are calculated. These error terms will also be discussed in Section 3.1. Note an interesting difference between the conventional equations for errors in the x and c data blocks in the former the mean is subtracted from the overall sum of... [Pg.14]

Fig. 3.15. J-V characteristics of Schottky diodes with b- For a non-zero Schottky barrier curves B deviate from curves A as applied voltages increases. Curves B become straight lines at higher voltages where C is large. These straight lines correspond to Ohm s law as predicted by Eq. (3.49). The values of the parameters in these calculations are the same as given in Fig. 3.11 [44],... Fig. 3.15. J-V characteristics of Schottky diodes with <pg = 0 and for finite (non-zero) values of (jig are plotted. Curves A correspond to conventional equation (3.42) and curves B correspond to Eq. (3.46) for different values of 4>b- For a non-zero Schottky barrier curves B deviate from curves A as applied voltages increases. Curves B become straight lines at higher voltages where C is large. These straight lines correspond to Ohm s law as predicted by Eq. (3.49). The values of the parameters in these calculations are the same as given in Fig. 3.11 [44],...
Fig. 3.17. J-V characteristics of the ITO/PEDOT PSS/MEH-PPV/Au diode at 240 K. The thickness of the active layer is 120 nm. The symbols represent die experimental data. The dash-dot line represents the ohmic region due to thermally generated and background carriers. The dashed line represents die calculated values using the conventional equation (3.42) with a zero Schottky barrier, while die dotted curve represents the calculated values using Eq. (3.46) with a Schottky barrier = 0.1 eV. At lower voltages below die point D, the plot of Eqs. (3.46) and (3.42) are practically identical. The values of die parameters used in this representation are N0 = 1019 cm-3, Tc = 400 K, e = 3, e0 = 8.85x 1(T14 F/cm, fi = 7x 1(T5 cm2/Vs, iVv = 2x 1019 cm-3 and Hh = 4.5 x 1018 cm-3 [44],... Fig. 3.17. J-V characteristics of the ITO/PEDOT PSS/MEH-PPV/Au diode at 240 K. The thickness of the active layer is 120 nm. The symbols represent die experimental data. The dash-dot line represents the ohmic region due to thermally generated and background carriers. The dashed line represents die calculated values using the conventional equation (3.42) with a zero Schottky barrier, while die dotted curve represents the calculated values using Eq. (3.46) with a Schottky barrier = 0.1 eV. At lower voltages below die point D, the plot of Eqs. (3.46) and (3.42) are practically identical. The values of die parameters used in this representation are N0 = 1019 cm-3, Tc = 400 K, e = 3, e0 = 8.85x 1(T14 F/cm, fi = 7x 1(T5 cm2/Vs, iVv = 2x 1019 cm-3 and Hh = 4.5 x 1018 cm-3 [44],...
The radiative losses can be calculated using the conventional equations [11]. The temperature rise dependence contains terms for the electric field strength, dielectric loss factor, heat capacity, and emissivity, and many of these are also temperature dependent. As a result, the complete theoretical analysis of dielectric heating is mathematically very complex [1],... [Pg.381]

The fits of the curves to the data are seen to display the rapid initial drop followed by the slower decline in endurance that is responsible for the curvature in the semilogarithmic plots. Scheme 2 can also potentially explain an initial increase in a measured property on aging by postulating that an initial concentration of intermediate X is present such that, with appropriate rate constants, the conversion of X into P will be faster than the transformation of P into X. A third feature of the above scheme is that when k12 and ki3 greatly exceed ki4, the property P will quickly reach a quasiequilibrium value of ki2/k z)F0 and then decay by first-order kinetics. When k 2 >> ki3, the kinetics will be first-order from the beginning, so that in limiting cases the conventional Equation 1 is obtained. [Pg.183]

We should also note that Arney et al. (7), have shown recently that the loss of some properties of paper could be represented as the sum of two pseudo first-order processes, one oxygen independent and one linearly dependent on the oxygen concentration. The model corresponding to this result would then be Equation 18, which is equivalent to the conventional Equation 1... [Pg.185]

The values of free energy changes are normally reported at standard conditions. In biochemistry, in addition to the requirement of unit activity for the concentrations of reactants and products, pressure of one atmosphere, and temperature of 25°C, the hydrogen ion concentration is arbitrarily set at pH 7.0. Following this convention, Equation (15.11) may be written as... [Pg.676]

One purpose of this section is to obtain two results concerning the rest points of certain vector fields that have the monotonicity properties described in Appendix C. Consequently, we will use the notation from that appendix. As the applications of our results come from Chapters 5 and 6 and it will frequently be necessary to refer to numbered equations from one of these chapters, we use the following convention equation number (5.2.4) will refer to equation (2.4) in Chapter 5. [Pg.284]

Hydraulic channel diameter d, was assumed to be a defining parameter for the first model, while equivalent particle diameter 4 was chosen for the second model. The conventional equation for computing hydraulic resistance is known to be ... [Pg.1214]


See other pages where Conventional equations is mentioned: [Pg.155]    [Pg.134]    [Pg.134]    [Pg.101]    [Pg.609]    [Pg.285]    [Pg.406]    [Pg.286]    [Pg.36]    [Pg.390]    [Pg.189]    [Pg.114]    [Pg.385]    [Pg.189]    [Pg.7]    [Pg.556]    [Pg.285]    [Pg.27]    [Pg.250]    [Pg.7]   
See also in sourсe #XX -- [ Pg.240 ]




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