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Similarity solution, closed form

A closed form similarity solution for the nonlinear time-dependent slow-flow equations has been used as the basis for a simple, time-dependent, analytic model of localized ignition which requires minimal chemical and physical input (8). As a fundamental part of the model, there are two constants which must calibrated the radii, or fraction of the time-dependent simi-... [Pg.345]

What makes eq. (1) difficult to solve is the presence of the Vee two-electron operator. Without it, the solution would be straightforward, as is the case for all hydrogen-like systems where we have one electron under the influence of a central field. Hydrogen-like systems are the only cases where analytic solutions are known in closed form. These solutions, or functions very similar to them, are the most natural basis to use in seeking the solutions for systems with more than two electrons. One approach is to treat one electron at a time and solve for this particular electron when it is under the average field of the others and nuclei. This is known as the central field approximation, and is the basis for the treatment of larger systems. [Pg.4]

Singular integral equation analysis. A closed-form analytical solution can be obtained. Observe that the standard source solution log r, centered at the origin r = + y ) = 0, solves Equation 2-41 for Similarly, the... [Pg.28]

The salts of some enamines crystallize as hydrates. In such cases it is possible that they are derived from either the tautomeric carbinolamine or the amino ketone forms. Amino ketone salts (93) ( = 5, 11) can serve as examples. The proton resonance spectra of 93 show that these salts exist in the open-chain forms in trifluoroacetic acid solution, rather than in the ring-closed forms (94, n = 5, 11). The spectrum of the 6-methylamino-l-phenylhexanone cation shows a multiplet at about 2.15 ppm for phenyl, a triplet for the N-methyl centered at 7.0 ppm and overlapped by signals for the methylene protons at about 8.2 ppm. The spectrum of 93 ( = 11) was similar. These assignments were confirmed by determination of the spectrum in deuterium oxide. Here the N-methyl group of 93 showed a sharp singlet at about 7.4 ppm since the splitting in —NDjMe was much reduced from that of the undeuterated compound. [Pg.275]

The relations (pA)a = (fijdp 5 (Fb) = (Pb)p would only by the merest chance form the solution of (2), hence there will not in general be a partition equilibrium between the ions when one is established between the neutral.molecules, but one solvent, say a, will contain more A ions than corresponds with ionic partition equilibrium. These will pass through the surface of contact into /3, and similarly B ions from /3 to a. The separation of the two kinds of ions will however set up an electrostatic field across the boundary, and the two kinds of ions collect there in two sheets very close together—in fact, we have an electrical... [Pg.470]

The expressions of the Sections 1.5 and 1.6 are general and apply to any solution of the Schrodinger equation. In the special case of a Morse potential, the radial integrals in Eq. (1.34) can be evaluated, with some approximations, in closed form. The approximation consists in replacing the lower limit of integration by -oo. This approximation is similar to that used in Section 1.3 when obtaining the wave functions. Thus... [Pg.15]

Dunitz, in his review (82), describes also studies on other systems. It should be mentioned that in the O - - C=0 interaction the correlation is poorer than inN C=0, presumably because the interaction is weaker and more sensitive to perturbation. However, compounds 39 and 40 of this series are worthy of note. The keto acid 39a and the isomeric lactone alcohol 39b are in dynamic equilibrium in solution at room temperature, and are present in similar concentrations. This substance has been obtained in only one crystal modification, corresponding to die closed form, 39b. However, the pattern of bond lengths... [Pg.156]

Using the case of S = 5/2 as an illustrative example, he demonstrated that it was possible to derive closed-form analytical expressions for the PRE of the form of the SBM equations times (1 + correction term). For typical parameter values, the effect of the correction term was to increase the prediction of the SBM theory by 5-7%. A similar approach was also applied to the S = 7/2 system, such as Gd(III) (101), where the correction terms could be larger. For that case, the estimations of the electron spin relaxations rates, obtained in the solution for PRE, were also used for simulations of ESR lineshapes. [Pg.74]

Three to several colonies for each sample are inoculated into the same 600 pL of LB medium containing 50 pg/mL of kanamycin and cultured at 37°C overnight. For glycerol stock, 50 pL of the culture is added to 25 pL of Cell Stock Buffer in a 96-well plate. The remaining suspensions are applied to the plasmid preparation with the Wizard SV 96 Plasmid DNA Purification System see Note 6). One microliter of the resultant plasmid solution is directly applied to agarose gel electrophoresis for estimation of the size of plasmid in a form of covalently closed circular. Similarly, another 1 pL of the plasmid solution is treated with S fi/Pmel and analyzed by agarose gel electrophoresis for an insert size check. This plasmid solution set is the final product and is reserved in a freezer. [Pg.34]

The structure of NR4F is closely similar to that of ice (see the following section) the atoms are similarly arranged, and the dimensions differ by only 3.7 percent (N—H--F, 2.66 A O-—2.76 A). It has been found44 that the two substances form crystalline solutions containing as much as 10 percent ammonium fluoride. Ammonium fluoride is the only substance known to have appreciable solubility, in ice. [Pg.464]

An interesting class of exact self-similar solutions (H2) can be deduced for the case where the newly formed phase density is a function of temperature only. The method involves a transformation to Lagrangian coordinates, based upon the principle of conservation of mass within the new phase. A similarity variable akin to that employed by Zener (Z2) is then introduced which immobilizes the moving boundary in the transformed space. A particular case which has been studied in detail is that of a column of liquid, initially at the saturation temperature T , in contact with a flat, horizontal plate whose temperature is suddenly increased to a large value, Tw T . Suppose that the density of nucleation sites is so great that individual bubbles coalesce immediately upon formation into a continuous vapor film of uniform thickness, which increases with time. Eventually the liquid-vapor interface becomes severely distorted, in part due to Taylor instability but the vapor film growth, before such effects become important, can be treated as a one-dimensional problem. This problem is closely related to reactor safety problems associated with fast power transients. The assumptions made are ... [Pg.102]

Several groups (84-86) have extended the similarity analysis of Burton et al. (73) to the case in which an axial magnetic field is imposed on the melt with sufficient strength such that Ha >> 1 and N 1. With these limits, a closed-form asymptotic expression describes the variation in the flow field across the thin 0(Ha 1/2) Hartmann layer adjacent to the disk. Axial solute segregation across this layer was analyzed by assuming that the melt outside of the Hartmann layers is well mixed. The effective segregation coefficient approaches 1 when the field strength is increased, as expected for any mechanism that damps convection near the crystal. [Pg.80]

Skaggs and Kabala studied a ID solute transport through a saturated homogeneous medium problem with a complex contaminant release history and assumed no prior knowledge of the release function. This closed form solution is similar to Eq. (50). Due to this similarity, Eq. (46) can be utilized to estimate the concentration release history (Cr). The accuracy of the TR method depends on the regularization parameter a. [Pg.86]

A master equation similar to Eq. (6.16.15) for dibasic acids would require solving a quartic equation and is impractical for a tribasic acid, a master equation would require solving a quintic equation, for which no closed-form solutions are possible in all these cases, useful approximations deal only with the significant concentrations and thus involve at most quadratic equations. [Pg.363]

Equation 29 and other closed form solutions for k (31.32) give very similar results note the structure in (30 percent Pb) in Figure 1. The dipole resonance frequency is given by Equation 20. Finally, we also note that at lower concentrations of Pb, agreement between experiment and theory is much improved (39). [Pg.243]

Solutions. A solution is defined as a homogeneous mixture of two or more substances, which has tlie same chemical composition and the same physical properties throughout. All gas mixtures are examples of solutions since gases are completely miscible with one another. Similarly, liquid mixtiues of alcohol and water are solutions since they too are homogeneous, single-phase systems. On the other hand, a liquid hydrocarbon and water do not form solutions since these two liquids do not dissolve in one another and a heterogeneous, two-phase system results. In general, the more closely two substances resemble one another chemically, the more likely are they to form a solution. [Pg.79]

State was attained. After UV-light irradiation, about 80% of the absorbance at 580 nm was recovered. The conversion of 80% from 2a to 2b was almost the same as that in the solution phase. The conversion of the film prepared from 2a solution was 40%, which is half of the conversion of the film prepared from a solution of the closed-ring form isomer. This difference in the maximum conversion to 2b is caused by the conformation of the open-ring form isomers. The isomer has two conformations, anti-parallel and parallel conformations. The former is photoactive whereas the latter is inactive, and half of the open-ring form isomers are in the inactive parallel conformations in solution. Half of 2a molecules in the film prepared from 2a solution are in the inactive parallel conformation. The conformational change is difficult in the amorphous film below Tg. In contrast, 2a in the bleached film prepared from the solution of 2b is in an anti-parallel conformation, and the maximum conversion to 2b at the photostationary state is about two times larger than that in the film prepared from 2a solution. A similar increase in the conversions in the film prepared from the closed-form isomer has been observed in amorphous diarylethenes, 3-10. It should be noted that heat treatment of the bleached 7a film at a temperature above Tg resulted in a decrease in the maximum conversion, which indicates that conformational change takes place at temperatures above Tg. [Pg.546]


See other pages where Similarity solution, closed form is mentioned: [Pg.363]    [Pg.33]    [Pg.224]    [Pg.214]    [Pg.246]    [Pg.329]    [Pg.153]    [Pg.338]    [Pg.139]    [Pg.396]    [Pg.366]    [Pg.24]    [Pg.138]    [Pg.770]    [Pg.77]    [Pg.271]    [Pg.186]    [Pg.111]    [Pg.123]    [Pg.174]    [Pg.548]    [Pg.43]    [Pg.421]    [Pg.415]    [Pg.134]    [Pg.3005]    [Pg.421]    [Pg.276]    [Pg.43]    [Pg.398]    [Pg.193]    [Pg.142]    [Pg.107]   
See also in sourсe #XX -- [ Pg.345 ]




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Closed form

Similarity solution

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