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Normal form method

A first application of the normal form method is the proof of the theorem of Kolmogorov on the persistence of invariant tori. We outline here the basic scheme proposed in Kolmogorov s original paper. [Pg.13]

Other limitations may be imposed by the material being moulded. It is difficult to thermoform nylon sheet, for instance, because nylon materials usually have fairly sharp melting points, thus rendering temperature control very critical — too critical for most commercial operations. Other materials, such as PTFE, are far too viscous for normal forming methods, however strongly heated, and articles must be made by powder sintering processes. [Pg.45]

Lithium Niobate. Lithium niobate [12031 -64-9], LiNbO, is normally formed by reaction of lithium hydroxide and niobium oxide. The salt has important uses in switches for optical fiber communication systems and is the material of choice in many electrooptic appHcations including waveguide modulators and sound acoustic wave devices. Crystals of lithium niobate ate usually grown by the Czochralski method foUowed by infiltration of wafers by metal vapor to adjust the index of refraction. [Pg.226]

In addition to modification of the catalyst, several variants of the Biginelli reaction have emerged as viable alternatives however, each method requires pre-formation of intermediates that are normally formed in the one-pot Biginelli reaction. First, Atwal and coworkers reported the reaction between aldol adducts 39 with urea 40a or thiourea 40b in the presence of sodium bicarbonate in dimethylformamide at 70°C to give 1,4-dihydropyrimidines 41. DHPM 42 was then produced by deprotection of 41. [Pg.514]

When enamines are treated with alkyl halides, an alkylation occurs that is analogous to the first step of 12-14. Hydrolysis of the imine salt gives a ketone. Since the enamine is normally formed from a ketone (16-12), the net result is alkylation of the ketone at the a position. The method, known as the Stork enamine reaction is an alternative to the ketone alkylation considered at 10-105. The Stork method has the advantage that it generally leads almost exclusively to monoalkylation of the ketone, while 10-105, when applied to ketones, is difficult to stop with the introduction of just one alkyl group. Alkylation usually takes place on the less substituted side of the original ketone. The most commonly used amines are the cyclic amines piperidine, morpholine, and pyrrolidine. [Pg.787]

When a user clicks on a typed entity in the Web interface the UltraLink Web Service is called, a connection to the Web Service is established, and the component is accessed. A method named GetLinks is then called together with the following parameters the type of the concept, the normalized form, and the raw text as encountered in the source document (the so-called lemma). [Pg.738]

Let S be a monadic recursion scheme. By methods similar to the proof of Chomsky normal form for context-free grammars we can convert the equations of S to the forms ... [Pg.321]

Later, Kuppermann and Belford (1962a, b) initiated computer-based numerical solution of (7.1), giving the space-time variation of the species concentrations from these, the survival probability at a given time may be obtained by numerical integration over space. Since then, this method has been vigorously followed by others. John (1952) has discussed the convergence requirement for the discretized form of (7.1), which must be used in computers this turns out to be AT/(Ap)2normalized forms of r and t. Often, Ar/(Ap)2 = 1/6 is used to ensure better convergence. Of course, any procedure requires a reaction scheme, values of diffusion and rate coefficients, and a statement about initial number of species and their distribution in space (vide infra). [Pg.200]

Reducing general problems to normal form. The two-phase simplex method... [Pg.338]

After completing the first phase we have a feasible basic solution. The second phase is nothing else but the simplex method applied to the normal form. The following module strictly follows the algorithmic steps described. [Pg.340]

The anharmonicities of the potential contribute by the terms involving the constants x, g, y,. .. as well as the energy shifts AEx = 0(h2),. .. and the frequency shifts Aw, = 0(h2),. These anharmonic constants can be calculated by the Van Vleck contact transformations [20] as well as by a semi-classical method based on an h expansion around the equilibrium point [14], which confirms that the Dunham expansion (2.8) is a series in powers of h. Systematic methods have been developed to carry out the Van Vleck contact transformations, as in the algebraic quantization technique by Ezra and Fried [21]. It should be noted that the constants x and g can also be obtained from the classical-mechanical Birkhoff normal forms [22], The energy shifts AEx,... [Pg.497]

The difficulties of considering solvated hydrogen ions increase when a weak acid is dissolved in a mixed solvent of two or more components, several of which form solvated species with the hydrogen ion. If, or when, the individual species can be identified and their concentrations determined, the normal thermodynamic methods in terms of all of the independent equilibria involved could be used without any assumptions. Without this information, the assumption of unsolvated acid species is justified and most convenient. [Pg.309]

Considering the nature of the forces involved in the physical adsorption process (see Section 4.2.1), it is evident that the adsorption isotherm of a given adsorptive on a particular solid at a given temperature depends on the nature of both the gas and the solid, and therefore, each adsorbate-adsorbent system has a unique isotherm. In spite of this, a number of attempts have been made to express the adsorption isotherm data in a normalized form. It was seen that, for a large number of nonporous solids (type II isotherms), the plot of n/nm versus P/P° can be represented by a single curve, called the standard isotherm. Among these related attempts, the t- and as-methods are the most widely used. [Pg.121]

Using the normal titration method on morpholine-treated paper samples, reserve alkalinity levels of less than 1% are found. However, in view of the previously mentioned possibilities for interaction between cellulose and morpholine and the observed reduction in the aging rate of morpholine-treated paper, it was thought likely that morpholine could be present in a form not immediately titratable but which might still offer some degree of protection against acid attack. [Pg.88]

Three isotopes of hydrogen are known H, 2H (deuterium or D), and 3H (tritium or T). Although isotope effects are greatest for hydrogen, justifying the use of distinctive names for the two heavier isotopes, the chemical properties of H, D, and T are essentially identical except in matters such as rates and equilibrium constants of reactions in addition, diverse methods of isotope separation are known. The normal form of the element is the diatomic molecule the various possibilities are H2, D2, T2, HD, HT, and DT.1 Naturally occurring hydrogen contains 0.0156% deuterium, whereas tritium occurs naturally in amounts of the order of 1 in 1017. [Pg.51]

Finding a coordinate system that minimizes the coupling between the DOFs has always been a natural aspiration in theoretical chemistry. The so-called reaction-path formalism is just such a procedure, as is the use of Normal-Form theory [13], which is our method of choice. Normal-Form theory gives us sufficient conditions for a Hamiltonian to be transformed into the form of Eq. (1) in the neighborhood of an equilibrium point of center (g) center g) saddle type. This result is well known (see, e.g.. Ref. 13). To summarize, first we perform a Taylor expansion of the Hamiltonian [Eq. (1)] ... [Pg.184]


See other pages where Normal form method is mentioned: [Pg.311]    [Pg.395]    [Pg.742]    [Pg.530]    [Pg.778]    [Pg.32]    [Pg.82]    [Pg.200]    [Pg.162]    [Pg.263]    [Pg.39]    [Pg.609]    [Pg.307]    [Pg.334]    [Pg.1025]    [Pg.531]    [Pg.38]    [Pg.395]    [Pg.403]    [Pg.70]    [Pg.567]    [Pg.187]    [Pg.147]    [Pg.19]    [Pg.96]    [Pg.403]    [Pg.404]    [Pg.487]    [Pg.1160]    [Pg.160]    [Pg.21]   
See also in sourсe #XX -- [ Pg.276 , Pg.531 ]




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Normal form

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