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Helmholtz optimization

Ouchterlony technique, 9 754 Ouricouri wax, 26 210—211 Ouricury, in mascara, 7 862 Outer approximations (OA), discrete optimization via, 26 1024 Outer—Helmholtz plane (OHP), 3 419 Outer-sphere (OS) mechanism,... [Pg.659]

To date, two arrangements of NMR coils, the solenoidal radio frequency (RF) coil (Figure 2A) and the saddle-type (Helmholtz) RF coil (Figure 2B) have been employed as on-line NMR detectors with CE and CEC. Theoretical studies have shown that reduction of the diameter of the RF coils increases the coil sensitivity [32], The miniaturized versions of saddle types are commonly used in commercial probes. As a major development, a saddle coil which houses 1.7-mm-diameter sample tubes has been introduced by Varian. Another significant contribution is the designing of an inverse coil to accommodate 3-mm-diameter sample tubes with a detection volume of 60 pL and a total volume of 140 pL [33], Fabrication procedures hinder further reduction of diameter of saddle-type coils that are optimized for sample volumes smaller than —1 pL. [Pg.316]

Considering a nonlinear chemical reaction, a practical solution may be obtained by the integration of the Gibbs-Helmholtz equation from equilibrium to optimal state... [Pg.435]

In the recent years, the g mixing rules have been further optimized. The main target is to get a low reference pressure to obtain a maximum similarity to the activity coefficient models. The first step was the relationship of Mollerup [13] which connects the excess Helmholtz energy and the excess Gibbs energy go at zero pressure ... [Pg.168]

In Eq. (4.9) Ahs is the Helmholtz free energy of the hard core reference system with the optimized hard core diameter. The pressure the fiiU system can be found from Eq. (4.9) by differentiation with respect to volume. This [Hessure will be a function of the two Lennard-Jones parameters au and 8. [Pg.340]

Another technique to obtain the effects of the anharmonic terms on the excitation frequencies and the properties of molecular crystals is the Self-Consistent Phonon (SCP) method [71]. This method is based on the thermodynamic variation principle, Eq. (14), for the exact Hamiltonian given in Eq. (10), with the internal coordinates not explicitly considered. As the approximate Hamiltonian one takes the harmonic Hamiltonian of Eq. (18). The force constants in Eq. (18) are not calculated at the equilibrium positions and orientations of the molecules as in Eq. (19), however. Instead, they are considered as variational parameters, to be optimized by minimization of the Helmholtz free energy according to Eq. (14). The optimized force constants are found to be the thermodynamic (and thus temperature dependent) averages of the second derivatives of the potential over the (harmonic) lattice vibrations ... [Pg.409]

In the mid 1980 s, Schmidt and Wagner" and Jacobsen et al developed equations of state that can be regarded as the origin of most of the recent so called reference equations of state. In this approach, optimization algorithms were used for the first time to determine the functional form of equations of state. In the equation by Schmidt and Wagner, the reduced Helmholtz energy is given by ... [Pg.411]

This is not yet the thermodynamic free energy because 7 has not been optimized. For this purpose, impose the constraint (dFildri) = 0. It is intuitively evident that at sufficiently low temperatures the last term, involving the temperature, will be small relative to the first. Thus, in first-order approximation, no appreciable error is made in adopting Eqs. (5.12.13) and (5.12.14) as the appropriate optimizations. This conjecture is confirmed by carrying out the required mathematical operation—a tedious operation that you should execute on your own. The resulting optimized dimensionless Helmholtz free energy (in units of W) for a half-filled band ( = 1) involves Eqs. (5.12.14) and (5.12.15) and reads... [Pg.332]

Ixabepilone is produced by semisynthesis from Epo B (2) and the development of this process was critically dependent on BMS collaboration with the Gesellschaft fur Biotechnologische Forschung (now the Helmholtz Institute for Infectious Research) in Braunschweig, Germany, which provided the BMS group with an optimized Epo B producing strain of S. cellulosum. The semisynthesis of ixabepilone (53) exploits the allylic nature of the... [Pg.113]

Nevertheless, optimizing with respect to f sometimes can be important. For example, the Helmholtz free energy difference A(1)-A(0) between two systems 1 and 0 can be written as... [Pg.164]


See other pages where Helmholtz optimization is mentioned: [Pg.519]    [Pg.211]    [Pg.38]    [Pg.46]    [Pg.344]    [Pg.432]    [Pg.2]    [Pg.131]    [Pg.104]    [Pg.141]    [Pg.220]    [Pg.669]    [Pg.244]    [Pg.167]    [Pg.116]    [Pg.114]    [Pg.187]    [Pg.149]    [Pg.322]    [Pg.23]    [Pg.165]    [Pg.714]    [Pg.322]    [Pg.139]    [Pg.799]    [Pg.186]    [Pg.80]    [Pg.81]   
See also in sourсe #XX -- [ Pg.81 ]




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