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Geometric progression

Since one molecule of enzyme usually catalyses the transformation of a number of substrate molecules, the reactions of such a sequence progress geometrically. If one assumes that in each case 1 molecule of enzyme acts on 10 molecules of substrate, it can be seen from Figure 25.12 that, after a two-stage process, 1 molecule of initial enzyme A would be responsible for the production of 100 molecules of product C while after a six-stage process one million molecules of active substance G would be produced. This effect would explain the relatively long latent period before clotting takes place and then the sudden explosive production of fibrin. [Pg.389]

For the Berry phase, we shall quote a definition given in [164] ""The phase that can be acquired by a state moving adiabatically (slowly) around a closed path in the parameter space of the system. There is a further, somewhat more general phase, that appears in any cyclic motion, not necessarily slow in the Hilbert space, which is the Aharonov-Anandan phase [10]. Other developments and applications are abundant. An interim summai was published in 1990 [78]. A further, more up-to-date summary, especially on progress in experimental developments, is much needed. (In Section IV we list some publications that report on the experimental determinations of the Berry phase.) Regarding theoretical advances, we note (in a somewhat subjective and selective mode) some clarifications regarding parallel transport, e.g., [165], This paper discusses the projective Hilbert space and its metric (the Fubini-Study metric). The projective Hilbert space arises from the Hilbert space of the electronic manifold by the removal of the overall phase and is therefore a central geometrical concept in any treatment of the component phases, such as this chapter. [Pg.105]

Even-tempered basis sets (M. W. Schmidt and K. Ruedenberg, J. Chem. Phys. 71, 3961 (1979)) consist of GTOs in which the orbital exponents ak belonging to series of orbitals consist of geometrical progressions ak = a, where a and P characterize the particular set of GTOs. [Pg.468]

A geometric progression is a succession of terms such that each term, except the first, is derivable from the preceding by the multiph-cation of a quantity / called the common ratio. AU such progressions have the form a, ar, ar, . . . , ar" "h With a = first term, I = last term, / = ratio, n = number of terms, s = sum of the terms, the following relations hold ... [Pg.431]

There have been other promising lines along which the theory of quenched-annealed systems has progressed recently. One of them, worth discussing in more detail, is the adsorption of fluids in inhomogeneous, i.e. geometrically restricted, quenched media [31,32]. In this area one encounters severe methodological and technical difficulties. At the moment, a set of results has been obtained at the level of a hard sphere type model adsorbed in sht-like pores with quenched distribution of hard sphere obstacles [33]. However, the problem of phase transitions has remained out of the question so far. [Pg.296]

Although intrinsic reaction coordinates like minima, maxima, and saddle points comprise geometrical or mathematical features of energy surfaces, considerable care must be exercised not to attribute chemical or physical significance to them. Real molecules have more than infinitesimal kinetic energy, and will not follow the intrinsic reaction path. Nevertheless, the intrinsic reaction coordinate provides a convenient description of the progress of a reaction, and also plays a central role in the calculation of reaction rates by variational state theory and reaction path Hamiltonians. [Pg.181]

Corollary 1.—If an ideal gas changes its volume reversibly without alteration of temperature, the quantities of heat absorbed or emitted form an arithmetical progression whilst the volumes form a geometrical progression (Sadi Carnot, 1824). [Pg.142]

Tenet (iv). The influence of a barrier layer in opposition to the progress of reaction may be expected to rise as the quantity of product, and therefore the thickness of the interposed layer, is increased [35,37,38]. Thus, the characteristic kinetic behaviour of the overall process may be expected to include contributions from both geometric factors and the barrier effect, though in specific instances one or other of these may be dominant. [Pg.7]

The maintenance of product formation, after loss of direct contact between reactants by the interposition of a layer of product, requires the mobility of at least one component and rates are often controlled by diffusion of one or more reactant across the barrier constituted by the product layer. Reaction rates of such processes are characteristically strongly deceleratory since nucleation is effectively instantaneous and the rate of product formation is determined by bulk diffusion from one interface to another across a product zone of progressively increasing thickness. Rate measurements can be simplified by preparation of the reactant in a controlled geometric shape, such as pressing together flat discs at a common planar surface that then constitutes the initial reaction interface. Control by diffusion in one dimension results in obedience to the... [Pg.286]

This is a geometric progression that sums to lN)ia the growing chains with length / is... [Pg.485]

Thus, we see that this problem has a unique solution if the value y is given for some i. For the sake of simplicity let be known in advance for i = 0. With this, one can determine all the values y-, y, . . by the recurrence formula just established. In the case qi z= q = const and ipi = 0 this provides support for the view that the whole collection of yi constitutes a geometric progression. If qi = q and (pi qb 0 then... [Pg.6]


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See also in sourсe #XX -- [ Pg.23 ]

See also in sourсe #XX -- [ Pg.4 ]




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