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Base function choice

The freedom that one has in the choice of the base function Q(z) will now be illuminated in a concrete way. For a radial Schrodinger equation the usual choice of Q2(z) is... [Pg.35]

A general one-pot procedure for the synthesis of alkynes from aldehydes (Corey-Fuchs reaction) that involves the synthesis of the triphenylphosphonium dibromomethane reagent has been explored by Michel and coworkers. In general, the base of choice is f-BuOK, but in case of the N-Boc piperidine, use of BuLi in order to avoid unwanted side reactions between the carbamate and the acetylide function provides a cleaner reaction at low temperature (eq 64). [Pg.65]

Diamine functionalized porous silica gel was used by Wang [81] as support for palladium complexes, which could be recycled up to 30 times. The copper-free reactions of aryl iodides and some aryl bromides were performed in EtOH as protic solvent with K2CO3 as base. Although these reactions could be conducted at ambient reaction temperature by immobilizing palladium on MCM-41 zeolites, they required the presence of Cu(I) additives and piperidine as the base of choice. [Pg.205]

With increasing quantity of effective steps Sj the chain end moves away from its origin, increasing the conformational volume where those SAW trajectories are localized at that end in one of 2 equiprobable cells Mp(s). That is why the cell quantity Z, allowed for a SAW trajectory, is not a fixed parameter of distribution (8.11), but a function of vector j=(5,) Z=Z(s). This function choice can be made based on different geometrical estimations (see Figure 8.1). [Pg.283]

By taking advantage of traditional synthetic chemistry, surface-based functional gronps can be modified through the formation of new chemical bonds (4,5,75). These covalent attachment schemes are used to modify the surface of an electrode. The reactions used for deriva-tization are determined by the identity of the chemical components on the electrode surface. Therefore, the choice of the modifier must account for the reactivity of the target surface site. [Pg.305]

Based on the same underlying principles as the molecular-based quantum methods, solid state quantum mechanics represents bulk material using periodic boundary conditions. The imposition of these boundary conditions means that it becomes possible to expand the electron density in periodic functions such as plane waves, as an alternative to the atom-based functions used in the molecular case. The efficiency of the calculations is enhanced by the use of pseudo-potentials to represent the core electrons and to make the electron density as smooth as possible near the nucleus, hence reducing the complexity of the plane wave expansion of the electron density. Because of the number of choices available for pseudo potentials, basis sets and whether calculations are done in real or reciprocal space, there are many choices of software for performing solid state quantum mechanical calculations. A few examples which have been used in crystal structure prediction include the Vienna ab initio Simulation Package (VASP), CASTEP and CRYSTAL. " A wider ranging introduction to the area can be found in the references. ... [Pg.53]

The transfer matrices Ta and Tb are computed from the transfer matrices of the plant and the base functions in the series expansion of the Youla parameter. Eq. (17) is a complete and convex description of all possible input-output behaviours of stable linear closed loops with the given plant. x,tj) depends on the choice of the external inputs Mf) and the external outputs z(0 as well as on the signals used for feedback and the available control inputs. [Pg.444]

Bakkestuen and Gimdersen performed the analogous N-arylation with 6-chlorop-urines (Scheme 5.19) [37]. The base of choice is phenanthroline, which is superior to 2,2 -dipyridy, TMEDA, and N,N -diarylethanediimines. Similar to Gray and Schultz s observation, only the N-9 arylated regioisomer was formed, even in the presence of a 2-amino functional group. [Pg.219]

It should also be noted that the criteria of productivity and energy consumption alone are insufficient criteria on which to base a choice of fermentor. The importance of maintaining a homogeneous "broth" could, in fact, be decisive if, for example, the functioning were to be disturbed by excessive sedimentation or foaming. On the other hand, while substrate yield depends on... [Pg.161]

Whilst SOFCs have developed significantly over the past few decades the main focus of materials development has been on the fluorite- and per-ovskite-based functional components. Each of the materials selections discussed above has deficiencies and there is now considerable effort directed towards the development of novel materials and structures with better performance for next generation SOFCs. In the following sections the potential choices available for low temperature electrolytes and cathodes and sulfur tolerant anodes will be discussed. [Pg.42]

The reconstruction algorithm proposed in this work is based on a special choice of basis flinctions to expand the unknown refractive index profile. The following set of functions is used here ... [Pg.129]

A potential advantage of methods based on a series expansion of the free energy is that the convergence of the series is determined by the A dependence of the potential energy function meaning that the efficiency of the approach could be enhanced by a judicious choice of coupling scheme. [Pg.152]

The measurements are predicted computationally with orbital-based techniques that can compute transition dipole moments (and thus intensities) for transitions between electronic states. VCD is particularly difficult to predict due to the fact that the Born-Oppenheimer approximation is not valid for this property. Thus, there is a choice between using the wave functions computed with the Born-Oppenheimer approximation giving limited accuracy, or very computationally intensive exact computations. Further technical difficulties are encountered due to the gauge dependence of many techniques (dependence on the coordinate system origin). [Pg.113]


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See also in sourсe #XX -- [ Pg.9 , Pg.33 , Pg.34 , Pg.35 , Pg.51 ]




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Base function

Function-based

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