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Step notation

The step notation [5, 16] compacts the terrace/step infonnation mto the general fomi w h k x Here... [Pg.1762]

A kinked surface, like fee (10,8,7), can also be approximately expressed in this fomi the step plane (h k / ) is a stepped surface itself, and thus has higher Miller indices than tlie terrace plane. However, the step notation does not exactly tell us the relative location of adjacent steps, and it is not entirely clear how the terrace width M should be counted. A more complete microfacet notation is available to describe kinked surfaces generally [5]. [Pg.1762]

A notation for these surfaces, the compact-step notation, devised by Lang and Somoijai [3], gives the surface structure in the general form w h,k,l,) X (h kj,), where hjc,l,) and h kj,) are the Miller indices of the terrace plane and the step plane, respectively, while w is the number of atoms that are counted in the width of the terrace, including the step-edge atom and the in-step atom. Thus, the fcc(755) surface is denoted by 7(111) x 1(100), or also by 7(111) x (100) for simplicity. A stepped surface with steps that are themselves high-Miller-index faces is termed a kinked surface. For example, the fcc(10, 8, 7) = 7(111) X (310) surface is a kinked surface. The step notation is, of course, equally applicable to surfaces of bcc, hep, and other ciystals, in addition to surfaces of fee crystals. Stepped surfaces of several orientations are listed in Table 2.2 (p. 88). Here the crystal faces are denoted both by their Miller indices and by their stepped-surface notation. [Pg.47]

An assessor has to ensure that the computer code is producing output in accordance with the model specifications. It is emphasized that the undertaking of model verification is an extremely tedious task. In the case of a computer implementation, the task is to prove in a step-by-step notation that the code does what it is supposed to do. The common practice is that developers take a less rigorous approach and perform verification by individually testing sections of the computer code (e.g., subroutines). In addition, developers should illustrate the model implementation by putting comment lines within the code. In general, the model evaluator will appeal to the developer to provide information on the extent the code has been verified. [Pg.439]

It is obvious from Figure 4.16 that giving just the Miller indices provides no good imagination about the microscopic characteristics of the surface. Therefore, more self-explaining notations were introduced. These are the so-called step notation on the one hand and the microfacet notation on the other. Both use - additional to the orientation of the terraces - the orientation of the microfacet making up the... [Pg.45]

Elsewhere in this chapter we shall see that other reactions-notably, chain transfer and chain inhibition-also need to be considered to give a more fully developed picture of chain-growth polymerization, but we shall omit these for the time being. Much of the argumentation of this chapter is based on the kinetics of these three mechanistic steps. We shall describe the rates of the three general kinds of reactions by the notation Rj, Rp, and R for initiation, propagation, and termination, respectively. [Pg.347]

On page 235-241 is the explicit solution used in Excel format to make studies, or mathematical experiments, of any desired and possible nature. The same organization is used here as in previous Excel applications. Column A is the name of the variable, the same as in the FORTRAN program. Column B is the corresponding notation and Column C is the calculation scheme. This holds until line 24. From line 27 the intermediate calculation steps are in coded form. This agrees with the notation used toward the end of the FORTRAN listing. An exception is at the A, B, and C constants for the final quadratic equation. The expression for B was too long that we had to cut it in two. Therefore, after the expression for A, another forD is included that is then included in B. [Pg.221]

Using matrix notation, these three steps are canied out as follows ... [Pg.186]

Table 11.3 One pass (read left to right) through the step.s of a basic genetic algorithm scheme to maximize the fitness function f x) = using a population of six 6-bit chromosomes. The crossover notation aina2) means that chromosomes Ca, and Ca2 exchange bits beyond the bit. The underlined bits in the Mutation Operation column are the only ones that have undergone random mutation. See text for other details. Table 11.3 One pass (read left to right) through the step.s of a basic genetic algorithm scheme to maximize the fitness function f x) = using a population of six 6-bit chromosomes. The crossover notation aina2) means that chromosomes Ca, and Ca2 exchange bits beyond the bit. The underlined bits in the Mutation Operation column are the only ones that have undergone random mutation. See text for other details.
Conversion tables and charts now available make it possible to express I.C.I. data in forms in which a specified color and the significance of measured color differences can be more easily visualized. For example, I.C.I. values calculated from objective instrumental readings can be converted into the Munsell notation which evaluates the three psychological color attributes—hue, lightness (Munsell value), saturation (Munsell chroma)—on scales of approximately equal visual steps. In addition, the Munsell color charts offer one of the most convenient sources of material standards for direct color comparisons. [Pg.11]

Quite often the step between a reactant A and an intermediate I is reversible. We adopt the notation shown ... [Pg.77]

Some tasks in the Test of Gained Knowledge required students to connect observations about the macro course of chemical reactions with their notations in the submicro and/or symbolic types of representation. The results indicate that most students were able to rearticulate the information about reactants and products of a chemical reaction from the textual description of chemical reaction into the form of word chemical equation (textual description of macros word equation of macro Task 8.2, f(o/ )=89.82% Task 9.1, f(o/ )=87.61%). This action corresponds to the first step in learning to write down chemical equation in the LON approach. It can easily be explained, because teachers described the learning process to be very efficient to this point, as is illustrated below ... [Pg.324]

These reactions could be elementary, first order, and without by-products as indicated. For example, they could represent a sequence of isomerizations. More Ukely, there will be by-products that do not influence the subsequent reaction steps and which were omitted in the shorthand notation of Equation (2.20). Thus, the first member of the set could actually be... [Pg.47]

The sieve analysis notation changed at some point in time, see batches 1, 23 and 24 in columns N-P, lines 19 and 21 The >45 y m value shifts from =92 to =7%. The customer had requested an additional specification <106 fim , which explains the row of dashes in line 19 up to column A an appropriate footnote should have been inserted. In connection with this, the specification in line 21 was changed from >45 to <45 correspondingly, all values had to be converted by hand, e.g., 93 = 100 - 7. (See table Step 1.)... [Pg.300]

The sides of rectangles, which constitute the domain G are assumed to be commensurable. All this enables us to place in the plane a grid with steps /ij and /ij so that the boundary of the grid domain lies on the boundary of the domain G. One trick we have encountered is to complete the domain G to the rectangle and then denote it by G (see Fig. 14). After that, we construct in G a difference grid and extend it to G. The notation will be used for the grid in the domain G. [Pg.281]

Here (j is the CG update parameter. In the above equations, e = e (tj) o vector notation for the discretized electric field strength, = g (fj) o objective functional J with respect to the field strength (evaluated at a field strength of e t) and dk = d (t ) o search direction at the feth iteration. The time has been discretized into N time steps, such as that tj=jx )t, where j = 0,1,2, , N. Different CG methods correspond to different choices for the scalar (j. ... [Pg.83]

More complicated surface structures that contain steps or even kinks may also be described in this notation as n(ht,kt,lt)x hs,ksh), which indicates that the surface contains n rows of atoms forming a terrace, and one step of (hsfsk) structure. [Pg.170]

The notation is also applicable to surfaces containing both steps and kinks, which results in a rough step. Thus, a (775) surface is equivalent to 6(lll)x(lll). In this manner all sorts of surfaces may be constructed. Of course, the question is whether these are stable or break up into facetted structures. [Pg.170]

In NIPALS one starts with an initial vector t with n arbitrarily chosen values (Fig. 31.12). In a first step, the matrix product of the transpose of the nxp table X with the n-vector t is formed, producing the p elements of vector w. Note that in the traditional NIPALS notation, w has a different meaning than that of a weighting vector which has been used in Section 31.3.6. In a second step, the elements of the p-vector w are normalized to unit sum of squares This prevents values from becoming too small or too large for the purpose of numerical computation. The... [Pg.134]

Suggest a convenient method for carrying out the following syntheses. The compound on the left is to be made from the one on the right (retrosynthetic notation). No more than three steps should be necessary. [Pg.464]


See other pages where Step notation is mentioned: [Pg.13]    [Pg.17]    [Pg.16]    [Pg.46]    [Pg.13]    [Pg.17]    [Pg.16]    [Pg.46]    [Pg.108]    [Pg.65]    [Pg.160]    [Pg.94]    [Pg.292]    [Pg.298]    [Pg.369]    [Pg.125]    [Pg.37]    [Pg.41]    [Pg.160]    [Pg.11]    [Pg.249]    [Pg.9]    [Pg.83]    [Pg.172]    [Pg.174]    [Pg.255]    [Pg.230]    [Pg.337]    [Pg.95]   
See also in sourсe #XX -- [ Pg.16 , Pg.81 , Pg.82 ]




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