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Common level surface

It is required to find a set of independent (almost everywhere) integrals /i> > /r> that their common level surfaces be sufficiently simple for instance, that all of them (in the case of general position) be diffeomorphic to a same simple manifold. Besides, it is also desirable that, being restricted to this common level surface, the initial system be transformed on it into a simply organized system, i.e., that the integral trajectories admit a simple description. [Pg.32]

For some Hamiltonian systems, there exists an extremely advisable partial integrability, for which the common level surface of integrab turns out to be a torus and the restriction to it of the initial system sets a conditionally-periodic motion along the torus. [Pg.32]

Thus, if the integrals fi,...,fn arc independent, then nonsingular compact common level surfaces are unions of tori Embedding each of these tori into an... [Pg.33]

This field turns out to he Hamiltonian on the common level surface of two integrals /2 = 2 = const, and /s = C3 = const, with respect to a certain natural Poisson bracket. This makes it possible to apply to this system the rich techniques used for the study of the general Hamiltonian systems. [Pg.35]

Let us consider the common level surface M23 of two integrals /2 and /s, that is, M23 = /2 = C2, /a = C3 > 0. This surface is a four-dimensional submanifold in R . Furthermore, the topological structure of this surface can be easily described. [Pg.35]

Hence, the degenerate Poisson bracket constructed above can be restricted (limited) to common level surfaces M23 of the integrals /2 and f. One can check that as a result, a nondegenerate Poisson bracket, arises already on the space of the functions defined on the manifold JI/23. [Pg.37]

Above, we have considered the case where the common level surface of the integrals H and / is compact. But it is not difficult to formulate and prove similar assertions for the noncompact case as well. We leave the details to the reader, since they can be easily worked out. [Pg.68]

Proof Since Xq is the common level surface of last integrals, their gradients form a basis in a plane normal to Xq in M. The dependence of the function fi on the... [Pg.111]

Here G is a A -dimensional linear space. Each point of this space determines a certain common level surface of the functions hat is, =... [Pg.147]

As the covector E G changes, its annihilator also changes somewhat in the Lie algebra G. The same change can be modulated by changing the common level surface of the basic functions /i,..., /fe ... [Pg.147]

The inequality K, e) < K )( i ) independence of the integrab /i, /2, fz on the common level surface M123 imply that > 0. Stable and unstable separatrix surfaces of the two indicated periodic (in t) solutions can be set as intersections of a three-dimensional manifold M123 by hyperplanes of the form... [Pg.265]

In this chapter we introduce and discuss a number of concepts that are commonly used in the electrochemical literature and in the remainder of this book. In particular we will illuminate the relation of electrochemical concepts to those used in related disciplines. Electrochemistry has much in common with surface science, which is the study of solid surfaces in contact with a gas phase or, more commonly, with ultra-high vacuum (uhv). A number of surface science techniques has been applied to electrochemical interfaces with great success. Conversely, surface scientists have become attracted to electrochemistry because the electrode charge (or equivalently the potential) is a useful variable which cannot be well controlled for surfaces in uhv. This has led to a laudable attempt to use similar terminologies for these two related sciences, and to introduce the concepts of the absolute scale of electrochemical potentials and the Fermi level of a redox reaction into electrochemistry. Unfortunately, there is some confusion of these terms in the literature, even though they are quite simple. [Pg.11]

The examples introduced above refer to the characterization of the most common types of catalysts, usually supported metals or single, mixed, or supported metal oxides. Many other materials such as alloys [199,200], carbides [201-203], nitrides [204,205], and sulfides [206] are also frequently used in catalysis. Moreover, although modem surface science studies with model catalysts were only mentioned briefly toward the end of the review, this in no way suggests that these are of less significance. In fact, as the ultimate goal of catalyst characterization is to understand catalytic processes at a molecular level, surface studies on well-defined model catalysts is poised to be central in the future of the field [155,174], The reader is referred to the Chapter 10 in this book for more details on this topic. [Pg.27]

Toners are comprised of a colorant in a resin binder. The colorant concentrations are typically 10%. Depending on the application, additional components may include additives to control the charge level, surface additives to control flow and cleaning, and/or waxes to prevent toner adhesion to the fuser roller. For black and white applications, the most common colorant is carbon black. The role of the resin is to bind the toner to the receiver, thus creating a permanent image. The choice of the resin depends on the fusing process. [Pg.17]

This difference is measurable. Changing the potential of the catalyst modifies its Fermi level, Ef, or in other terms, the electrochemical potential of the electrons in the catalyst, e ( = ) This latter is defined as the difference between the zero energy state of the electrons (taken at ground state at infinite distance from the solid) and the energy of a conduction electron in the bulk of the catalyst. It is common practice to count this energy difference in two conceptually different ways. One of them is common in electrochemistry, the other is common in surface science. [Pg.201]

Another major disadvantage of the commonly used surface complexation models, and of most equilibrium-based sorption models, is that three-dimensional surface products are not included as possible complexes. However, there are several exceptions. Farley et al. (5) and James and Healy (6) considered surface precipitation in successfully modeling sorption of hydrolyzable metal ions. Dzombak and Morel (7) modified the diffuse layer surface complexation model to include surface precipitation. However, these applications relied solely on macroscopic data without molecular-level identification of the sorption complex structure. Recently, Katz and Hayes (8,9) employed triple layer models, that included a surface solution model, a surface polymer model, and a surface continuum model to describe molecular level data for Co sorption on y-AljOj over a wide range of surface coverages (0.1 to 100%). [Pg.112]

Proof If T = then T is a common (singular) level surface of all n integrals /i) > /n Level surfaces Rj close to this surface, are nonsingular compact Liouville tori. It is clear that R is the boundary of a tubular neighbourhood of the... [Pg.113]

If the Hamiltonian H admits a correct embedding in a certain maximal linear subalgebra G, then defined is a certain (at least one) common nonsingular level surface C M which corresponds to the covector of general position... [Pg.148]

The question addressed here concerns the positions of energy levels of adsorbed molecules with respect to some common level. Clearly this question is directly related to the processes which involve charge transfer, particularly in chemical reactions at surfaces. If energy levels of atoms and molecules participating in the reaction are known, one could, in principle, predict the direction of the charge transfer and character of the chemical bond formed. From a physical point of view. [Pg.59]


See other pages where Common level surface is mentioned: [Pg.32]    [Pg.32]    [Pg.38]    [Pg.57]    [Pg.70]    [Pg.149]    [Pg.163]    [Pg.169]    [Pg.227]    [Pg.256]    [Pg.315]    [Pg.32]    [Pg.32]    [Pg.38]    [Pg.57]    [Pg.70]    [Pg.149]    [Pg.163]    [Pg.169]    [Pg.227]    [Pg.256]    [Pg.315]    [Pg.209]    [Pg.236]    [Pg.684]    [Pg.31]    [Pg.209]    [Pg.792]    [Pg.29]    [Pg.147]    [Pg.486]    [Pg.391]    [Pg.87]    [Pg.264]    [Pg.63]    [Pg.109]    [Pg.147]    [Pg.276]    [Pg.23]   
See also in sourсe #XX -- [ Pg.2 , Pg.32 ]




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