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Surface, equations

Figure XVI-1 and the related discussion first appeared in 1960 [1], and since then a very useful mathematical approach to irregular surfaces has been applied to the matter of surface area measurement. Figure XVI-1 suggests that a coastline might appear similar under successive magnifications, and one now proceeds to assume that this similarity is exact. The result, as discussed in Section VII-4C and illustrated in Fig. VII-6, is a self-similar line, or in the present case, a self-similar surface. Equation VII-21 now applies and may be written in the form... Figure XVI-1 and the related discussion first appeared in 1960 [1], and since then a very useful mathematical approach to irregular surfaces has been applied to the matter of surface area measurement. Figure XVI-1 suggests that a coastline might appear similar under successive magnifications, and one now proceeds to assume that this similarity is exact. The result, as discussed in Section VII-4C and illustrated in Fig. VII-6, is a self-similar line, or in the present case, a self-similar surface. Equation VII-21 now applies and may be written in the form...
After some algebraic manipulation, Eqs. (A, I) and (A.2) lead to the following single-surface equations [4]... [Pg.612]

Step 8 - the new values of the nodal velocities found at the end of step 7 are used as input and the free surface equation is solved. [Pg.146]

To simplify matters, it is assumed that the current densities for the partial reactions are independent of position on the electrode surface. Equation (2-10 ) can then be used to designate the current densities ... [Pg.44]

Fi i is the visibility factor between two finite surfaces, and AiF/ i = is the geometrical radiation surface. Equation (4.225) shows that the geometrical radiation surface is symmetric and therefore... [Pg.123]

If it is assumed that each element resides for the same time interval te in the surface, equation 10.115 gives the overall mean rate of transfer. It may be noted that the rate is a linear- function of the driving force expressed as a concentration difference, as in the two-film theory, but that it is proportional to the diffusivity raised to the power of 0.5 instead of unity. [Pg.606]

Equations 12.45 and 12.47 are applicable to both rough and smooth surfaces equation 12.46 is valid only for a smooth surface e/d 0). [Pg.709]

There are enough equations to eliminate the surface equations from the reaction rate. After redefinition of constants. [Pg.359]

Thus, integration over an arbitrary volume allows us to find the force caused by any distribution of masses. It is essential that the particle p can be located either outside or inside of a body and at any distance from its surface. Equation (1.3) describes the total force that is a result of a superposition of the elementary forces, vectors, at the same point. Correspondingly, this force can cause a translation of the particle only. It is also instructive to consider the force F generated by the particle and acting on an arbitrary body. Each elementary volume is subjected to the force... [Pg.4]

Beeause many adsorbents have heterogeneous surfaces. Equation 4.22 should be modified by introdueing of an additional eoefficient, resulting in Equation 4.28, so that it ean be used in systems employing such adsorbents ... [Pg.89]

Hydrogen electrosorbed at the metal (M) electrode surface (Equation (2)) is further desorbed electrochemically (Equation (3)) or chemically (Equation (4)). [Pg.473]

The more common approach is to treat the particle-gas suspension as an equivalent gray surface parallel to the heat transfer surface. Equation (11) would than be used with Ftaken as unity. Grace (1986) suggests that the emissivity of the particle-gas suspension can be approximated as,... [Pg.201]

Fischer-Tropsch synthesis can be regarded as a surface polymerization reaction since monomer units are produced from the reagents hydrogen and carbon monoxide in situ on the surface of the catalyst. Hence, a variety of hydrocarbons (mainly n-paraffines) are formed from hydrogen and carbon monoxide by successive addition of C, units to hydrocarbon chains on the catalyst surface (Equation 12.1). Additionally, carbon dioxide (Equation 12.3) and steam (Equations 12.1 and 12.2) are produced C02 affects the reaction just a little, whereas H20 shows a strong inhibiting effect on the reaction rate when iron catalysts are used. [Pg.216]

The purely reorientational broadening mechanism with a single threefold quasidegenerate subbarrier level is characteristic of the valence vibration spectral line for OH groups on Si02 surface. Equation (4.2.22) describes the observed temperature... [Pg.104]

In step (1), the solution of equation 9.1-18 requires two boundary conditions, each of which can be expressed in two ways one of these ways introduces die other two rate processes, equating the rate of diffusion of A to the rate of transport of A at the particle surface (equation 9.1-11), and also the rate of diffusion at the core surface to the rate of reaction on the surface (9.1-20), respectively. Thus,... [Pg.231]

The rate of a batch slurry reaction is controlled by diffusion from the bulk liquid to the surface of the catalyst and by a second order reaction on the surface. Equations for the two processes are rd = 0.25(C-Cs)... [Pg.725]

Intersection of the two potential energy surfaces [equations (3.14) and (3.15)] and determination of the saddle point, taking due account of the... [Pg.198]

Selective reduction of dienes may be influenced by the substituents, which can change the substrate orientation during adsorption on the catalyst surface (equation 65)158. It has to be mentioned that this effect worked only if low amounts of catalyst were used at higher amounts the selectivity decreased. [Pg.1019]

Since u] does not change with n, a geometrically plane surface is implied. Strictly, equation 17.10 is not applicable to highly convex or concave surfaces. Equations 17.9 and 17.10 may be combined to give ... [Pg.984]

The reason for this difficulty is that we are trying to fit a planar response surface (Equation 15.6) to data that have been obtained in a line (see Figure 15.2). An infinite number of planes can be made to pass through this line therefore, an infinite... [Pg.364]

The details in the CO response continue to be the subject of many discussions and a full explanation will need further studies. These can include spectroscopy studies such as diffuse reflectance transform infrared spectroscopy (DRIFT), which can be performed under realistic conditions [43,44], and theoretical modeling [45]. However it seems likely that not only hydrogen gives rise to charged or polarized complexes on the insulator surface. Equation (2.3) may now be written as... [Pg.34]


See other pages where Surface, equations is mentioned: [Pg.488]    [Pg.2841]    [Pg.146]    [Pg.153]    [Pg.279]    [Pg.948]    [Pg.344]    [Pg.345]    [Pg.207]    [Pg.42]    [Pg.141]    [Pg.722]    [Pg.192]    [Pg.23]    [Pg.299]    [Pg.265]    [Pg.819]    [Pg.436]    [Pg.131]    [Pg.159]    [Pg.304]    [Pg.135]    [Pg.65]    [Pg.371]    [Pg.95]    [Pg.107]    [Pg.95]    [Pg.225]   
See also in sourсe #XX -- [ Pg.386 ]




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