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The Complete Solution

To solve the kinetics for the most general case, in which, for example, we allow partial pressures to vary with time, we need the full set of differential equations describing the coverage of all species participating in the reaction  [Pg.58]

These equations can be solved numerically with a computer, without making any approximations. Naturally all the involved kinetic parameters need to be either known or estimated to give a complete solution capable of describing the transient (time dependent) kinetic behavior of the reaction. However, as with any numerical solution we should anticipate that stability problems may arise and, if we are only interested in steady state situations (i.e. time independent), the complete solution is not the route to pursue. [Pg.58]


From Eq. (9.1) we see that the viscous force associated with this motion equals [i7(dv/dr)] (area), where the pertinent area is proportional to the surface of the sphere and varies as. This qualitative argument suggests that the viscous force opposing the relative motion of the liquid and the sphere is propor tional to [t7(v /R)] (R ). The complete solution to this problem reveals that both pressure and shear forces arising from the motion are proportional tc 77Rvj., and the total force of viscous resistance is given by... [Pg.586]

For axial dispersion in a semi-infinite bed with a linear isotherm, the complete solution has been obtained for a constant flux inlet boundary condition [Lapidiis and Amundson,y. Phy.s. Chem., 56, 984 (1952) Brenner, Chem. Eng. Set., 17, 229 (1962) Coates and Smith, Soc. Petrol. Engrs. J., 4, 73 (1964)]. For large N, the leading term is... [Pg.1529]

Alumina sufficient to adsorb the complete solution is added, then the solvent is removed under vacuum. While benz[a]anthracene, np 157-158°C, sufficiently pure for most purposes, can be obtained by crystallization of the crude product from ethanol-water, filtration" through alumina removes residual, colored impurities, affording a pure, white product. [Pg.166]

Bulk is not usually the complete solution to foundation problems. A certain weight is sometimes necessary, but soil area is usually of more value than foundation mass. [Pg.565]

Radi, P Schumacher, E, Numerical Simulation of Electrophoresis The Complete Solution for Three Isotachophoretic Systems, Electrophoresis 6, 195, 1985. [Pg.619]

In solving the kinetics of a catalytic reaction, what is the difference between the complete solution, the steady-state approximation, and the quasi-equilibrium approximation What is the MARI (most abundant reaction intermediate species) approximation ... [Pg.403]

However, the complete solution of these three simultaneous differential equations is difficult to obtain and is no more instructive than the approximate solution that can be obtained by means of the steady-state approximation for intermediates. If one sets the time derivatives in equations 4.2.17 and 4.2.18 equal to zero and adds these equations, their sum is found to be... [Pg.93]

Most spectroscopic binaries have periods ranging from days to months and are separated by distances of order 1 AU. A consequence of knowing the period of the star and separation, measured optically, is the determination of the mass of the stars. Assuming that the two stars are in circular orbit, for the sake of simplicity, then a centripetal force is required to keep them moving in orbit. Gravity provides this attraction and the two forces must be balanced. The complete solution of this problem is hard and only a combined mass can be derived without knowing some information other than the period of rotation. [Pg.103]

The general solution is a superposition of stationary solutions with constant coefficients Cj. In this sense, a knowledge of the stationary states provides the complete solution to the problem. The probability that measuring the energy of the system would yield EJ follows immediately as cj 2. [Pg.196]

The complete solution of the non-homogeneous equation can be found directly in some cases by Laplace Transform, as the problems of section PI.04 show. [Pg.17]

The complete solution of these equations is worked out in problem P2.02.07. The plot is of the solution obtained numerically by program ODE. The peak value is B = 2.234 when t = 4.502. [Pg.302]

Fitting of the boundary conditions requires the complete solution to be an infinite series. Numerical solutions may be preferable, and are always required for other than first order reactions. [Pg.750]

Let us first build a model of the components in the complete solution as envisioned (see Figure 10.22). We have annotated it with the types from the requirements model, with a first guess of where these types will primarily be maintained. Life will not be so simple, of course. [Pg.455]

The ubiquity of lignin in plant tissue presents an obstacle to the removal and purification of xylan. Lignin retards or prevents the complete solution of xylan either because of mechanical obstruction or perhaps by reason of attachment through as yet unidentified covalent bonds. Furthermore, lignin is partially soluble in the various aqueous alkaline solutions used for dissolving xylan and, consequently, poses a purification problem in various subsequent steps designed to isolate the pure polysaccharide. [Pg.287]

It can be shown by an exactly similar process that when v is an integer the complete solution of the equation (30.1) is... [Pg.106]

Show that the complete solution of Bessel s equation may be written in the form... [Pg.129]

Although the complete solution of ux at J will not be attempted at this point, it can be shown readily that the detonation velocity has a simple expression now that u2 and c2 have been shown to be equal. The conservation of mass equation is rewritten to show that... [Pg.274]

Solutions to most problems are contained in the literature cited. Therefore only hints are given in a few cases the complete solution or numerical answer is provided. [Pg.443]

Finally, you need to form the carbanion at the beginning of Figure 17-13. This step completes this retrosynthetic analysis problem. The complete solution is in Figure 17-14. [Pg.322]

However, the ideas in the examples given are still very useful in dealing with more complex problems because simple examples with analytical solutions allow us to estimate reactor performance quickly without resorting to complex numerical solutions. Further, the kinetics of the complete reactions are frequently unknown, or, if rate expressions are available, there may be large errors in these rate parameters that will make even the complete solution approximate. This is especially true for surface-catalyzed reactions and biological reactions, where the rate expressions are complex with fractional orders and activation... [Pg.180]

Fig. 11.5 Dependence of time required to reach 50% of steady terminal velocity (1% = 0.5) on aspect ratio for rigid spheroids. Solid lines give ratio of t for spheroids to that for a sphere of the same equatorial diameter. Broken lines give the ratio of t from Eq. (11-20) neglecting history terms to the value from the complete solution. Analysis is for creeping flow. Fig. 11.5 Dependence of time required to reach 50% of steady terminal velocity (1% = 0.5) on aspect ratio for rigid spheroids. Solid lines give ratio of t for spheroids to that for a sphere of the same equatorial diameter. Broken lines give the ratio of t from Eq. (11-20) neglecting history terms to the value from the complete solution. Analysis is for creeping flow.
The complete solutions to (5) will be referred to as Dirac solutions whereas the solutions to (8) with spin-orbit coupling omitted will be referred to as modified PauU solutions. [Pg.271]

Tables of thermodynamic data necessary to apply equations listed by Cook are given in Appendix II of his book. The complete solution of the thermohydrodynamic theory for condensed explosives may then be effected in principle by a simultaneous solution of eqs... Tables of thermodynamic data necessary to apply equations listed by Cook are given in Appendix II of his book. The complete solution of the thermohydrodynamic theory for condensed explosives may then be effected in principle by a simultaneous solution of eqs...
The user pays for the complete solution and further optimises it together with the tow other partners... [Pg.24]

Model is more complex and besides user and producer of the chemical also the equipment supplier with its specific process know-how is involved in the process. In this model the chemical producer together with the equipment supplier offer a solution that has been improved with regard to efficiency of chemicals and energy use. The user pays for the benefit of the complete solution and further improves efficiency of the offered solution related to its process. [Pg.25]


See other pages where The Complete Solution is mentioned: [Pg.985]    [Pg.232]    [Pg.439]    [Pg.460]    [Pg.225]    [Pg.215]    [Pg.116]    [Pg.21]    [Pg.58]    [Pg.487]    [Pg.17]    [Pg.36]    [Pg.230]    [Pg.106]    [Pg.291]    [Pg.34]    [Pg.106]    [Pg.277]    [Pg.71]    [Pg.200]    [Pg.323]    [Pg.273]   


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