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Fourier completeness

We use the sine series since the end points are set to satisfy exactly the three-point expansion [7]. The Fourier series with the pre-specified boundary conditions is complete. Therefore, the above expansion provides a trajectory that can be made exact. In addition to the parameters a, b and c (which are determined by Xq, Xi and X2) we also need to calculate an infinite number of Fourier coefficients - d, . In principle, the way to proceed is to plug the expression for X t) (equation (17)) into the expression for the action S as defined in equation (13), to compute the integral, and optimize the Onsager-Machlup action with respect to all of the path parameters. [Pg.271]

V (ro) is continuous and has continuous lirst derivatives over the interval [0.271 ], which is the complete interval of ffi. It is convenient to rename the interval [ n, tc] (which is the same as [0. 27t ]) for the following discussion. Any continuous function can he repi esented ovei this interval by the Fourier. ieries... [Pg.119]

Besides the intrinsic usefulness of Fourier series and Fourier transforms for chemists (e.g., in FTIR spectroscopy), we have developed these ideas to illustrate a point that is important in quantum chemistry. Much of quantum chemistry is involved with basis sets and expansions. This has nothing in particular to do with quantum mechanics. Any time one is dealing with linear differential equations like those that govern light (e.g. spectroscopy) or matter (e.g. molecules), the solution can be written as linear combinations of complete sets of solutions. [Pg.555]

In order to optimize each embedding material property, complete cure of the material is essential. Various analytical methods are used to determine the complete cure of each material. Differential scanning calorimetry, Fourier transform-iafrared (ftir), and microdielectrometry provide quantitative curing processiag of each material. Their methods are described below. [Pg.193]

Figures 6.4 shows some of the variety of possible shapes of P f) for elementary rules shown in the figures are the power spectra for rules Rll, R56, R150 and R200. The plots were generated for lattice size N = 2048, ignoring the first 15 transient steps and averaging a total of 20 runs. Also, since there are only N data points but 2N real Fourier components, half of the components are redundant. Thus, only the first half of the components are shown (see [H89b] or [H87] for a complete set of power spectra). Figures 6.4 shows some of the variety of possible shapes of P f) for elementary rules shown in the figures are the power spectra for rules Rll, R56, R150 and R200. The plots were generated for lattice size N = 2048, ignoring the first 15 transient steps and averaging a total of 20 runs. Also, since there are only N data points but 2N real Fourier components, half of the components are redundant. Thus, only the first half of the components are shown (see [H89b] or [H87] for a complete set of power spectra).
An amine-terminated poly ether (ATPE) is prepared as follows. Charge poly(tetramethylene oxide) diol (PolyTHF 1000, BASF, 75.96 g, 0.0759 m) to a 500-mL three-neck round-bottom flask fitted with a thermocouple, a mechanical stirrer, and a vacuum port. Add tert-butylacetoacetate (24.04 g, 0.1582 m) and apply vacuum. Heat at 175° C for 4 h, Fourier transform infrared (FTIR) analysis should indicate complete loss of the polyol OH absorption at 3300 cm. The room temperature viscosity of the product should be about 520 mPa-s. React this acetoacetylated product (85.5 g, 0.0649 m) with cyclohexylamine (14.5 g, 0.1465 m) at 110° C under vacuum for several hours. Cool the resultant cyclohexylaminocrotonate poly ether product to room temperature (1790 mPa-s at room temperature). [Pg.255]

At distances that are very large compared to either the source dimensions, or the aperture of our optical system the complex amplitude is just the Fourier transform of the object complex amphtude. Furthermore, it can be shown that the complex amplitude in the image plane of an optical system is just the Fourier transform of the complex amplitude at the aperture plane, (for a complete derivation of this see Goodman, 1996). [Pg.40]

Table 5.7 Theoretically predicted polypeptides from the trypsin digestion of S-lacto-globulin (/3LG) . Reprinted from J. Chromatogr., A, 763, Turula, V. E., Bishop, R. T., Ricker, R. D. and de Haseth, J. A., Complete structure elucidation of a globular protein by particle beam liquid chromatography-Fourier transform infrared spectrometry and electrospray liquid chromatography-mass spectrometry - Sequence and conformation of /3-lactoglobulin , 91-103, Copyright (1997), with permission from Elsevier Science... Table 5.7 Theoretically predicted polypeptides from the trypsin digestion of S-lacto-globulin (/3LG) . Reprinted from J. Chromatogr., A, 763, Turula, V. E., Bishop, R. T., Ricker, R. D. and de Haseth, J. A., Complete structure elucidation of a globular protein by particle beam liquid chromatography-Fourier transform infrared spectrometry and electrospray liquid chromatography-mass spectrometry - Sequence and conformation of /3-lactoglobulin , 91-103, Copyright (1997), with permission from Elsevier Science...
The wave function W(x, i) may be represented as a Fourier integral, as shown in equation (2.7), with its Fourier transform A p, t) given by equation (2.8). The transform A p, i) is uniquely determined by F(x, t) and the wave function F(x, t) is uniquely determined by A p, i). Thus, knowledge of one of these functions is equivalent to knowledge of the other. Since the wave function F(x, /) completely describes the physical system that it represents, its Fourier transform A(p, t) also possesses that property. Either function may serve as a complete description of the state of the system. As a consequence, we may interpret the quantity A p, f)p as the probability density for the momentum at... [Pg.40]

Here we briefly present the relevant theory of capillary waves. The thermally excited displacement (r, t) of the free surface of a liquid from the equilibrium position normal to the surface can be Fourier-decomposed into a complete set of surface modes as... [Pg.240]

An approach to solving the inverse Fourier problem is to reconstruct a parametrized spin density based on axially symmetrical p orbitals (pz orbitals) centered on all the atoms of the molecule (wave function modeling). In the model which was actually used, the spin populations of corresponding atoms of A and B were constrained to be equal. The averaged populations thus refined are displayed in Table 2. Most of the spin density lies on the 01, N1 and N2 atoms. However, the agreement obtained between observed and calculated data (x2 = 2.1) indicates that this model is not completely satisfactory. [Pg.53]


See other pages where Fourier completeness is mentioned: [Pg.1510]    [Pg.1607]    [Pg.1632]    [Pg.1646]    [Pg.1647]    [Pg.1769]    [Pg.1783]    [Pg.2962]    [Pg.285]    [Pg.542]    [Pg.148]    [Pg.399]    [Pg.482]    [Pg.482]    [Pg.82]    [Pg.31]    [Pg.555]    [Pg.30]    [Pg.509]    [Pg.213]    [Pg.30]    [Pg.197]    [Pg.605]    [Pg.629]    [Pg.793]    [Pg.267]    [Pg.266]    [Pg.117]    [Pg.10]    [Pg.149]    [Pg.133]    [Pg.60]    [Pg.152]    [Pg.418]    [Pg.313]    [Pg.337]    [Pg.397]    [Pg.734]    [Pg.348]   
See also in sourсe #XX -- [ Pg.114 ]




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