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Bounded similarity transformations

Let us start with some purely formal considerations. Let us consider a linear space A = and an operator U defined on this space, which maps it onto itself in a one-to-one way, so that [Pg.88]

Let us further consider a linear operator T defined on A = which maps [Pg.88]

Since the reverse is also true, the operators T and T have evidently the same eigenvalues. In the treatment of the general stability problem (5), one observes that, if the projector O reduces T, so that [Pg.89]

In many connections, it is convenient to introduce an abstract binary product Fl F2 associated with ordered pairs of elements of the linear space A = F, which is defined as linear in the second position, Hermitian symmetric, and positive definite  [Pg.89]

Using this concept, one may now introduce the adjoint operator T1 to the operator T through the relation [Pg.89]


For such a bounded operator, the spectral and general stability properties of the linear operator T stay essentially invariant under the transformation Eq. (1.2), and, for self-adjoint and normal operators, one has a series of well-known theorems. Before proceeding to the unbounded transformations, we will briefly review some additional properties of the bounded similarity transformations. [Pg.91]

The similarity transformation transforms a set of points S at position x = (xj,...,xE) in Euclidean E-dimensional space into a new set of points r(S) at position x = (rXj,...,rxE) with the same value of the scaling ratio 0self-similar with respect to a scaling ratio r if S is the union of N nonoverlapping subsets SU...,SN, each of which is congruent to the set r(S). Here congruent means that the set of points. S is identical to the set of points r(S) after possible translations and/or rotations. For the deterministic self-similar fractal, the selfsimilar fractal dimension dFss is clearly defined by the similarity... [Pg.351]

Fmoc group, but difficulties were experienced optimising aUyl cleavage using Pd catalysis - especially when the substrate was bound to a solid support. A useful development is the discovery that aUyl phosphates are cleaved with concentrated ammonia at 70 C under the same conditions used to cleave the oligonucleotide from the solid support.56 Similar transformations have been accomplished with 2% mercaptoethanol in concentrated ammonia at 55 °C 57... [Pg.433]

Rosse et al. described the oxidation of the resin-bound /3-sulfenyl hydroxamic acids A -sulfonyloxaziridines <2001SL538>. For example, oxidation of 143 with 33 afforded the corresponding sulfoxide 144 in 71% yield after cleavage of the resin with TFA. Apfel et al. in the preparation of some potent peptide deformylase inhibitors and antibacterial agents employed a similar transformation<2000JME2324>. [Pg.578]

High sorption capacities with respect to protein macromolecules are observed when highly permeable macro- and heteroreticular polyelectrolytes (biosorbents) are used. In buffer solutions a typical picture of interaction between ions with opposite charges fixed on CP and counterions in solution is observed. As shown in Fig. 13, in the acid range proteins are not bonded by carboxylic CP because the ionization of their ionogenic groups is suppressed. The amount of bound protein decreases at high pH values of the solution because dipolar ions proteins are transformed into polyanions and electrostatic repulsion is operative. The sorption maximum is either near the isoelectric point of the protein or depends on the ratio of the pi of the protein to the pKa=0 5 of the carboxylic polyelectrolyte [63]. It should be noted that this picture may be profoundly affected by the mechanism of interaction between CP and dipolar ions similar to that describedby Eq. (3.7). [Pg.22]

The vessel.. . must be round in shape. Thus the artifex must be the transformer of this firmament and of the brain-pan, just as the thing for which we seek is a simple thing having uniform parts. It is therefore necessary that you should generate in it a body of uniform parts.. . from the brain-pan, that is, from the head of the element Man, and that the whole should be macerated with urine. . . The vessel is made round after the fashion of upper and lower world. For it is similarly suited to that whose generation is sought in it, for a thing is bound by its like. ... [Pg.28]

The resin-bound trienes 83 (Scheme 11) were prepared in a similar fashion to the solution-phase studies (Sect. 2.2.2) and underwent tandem RCM resin-cleavage to liberate four macrolactones 84a,b and 85a,b in a combined yield of 52%. Although, as expected, a large amount of initiator 3 was required to effect this transformation, the procedure constituted a novel and efficient route to the epothilones which paved the way for the generation of a library of epothilone analogs. The library synthesis was achieved using the recently developed SMAR-I9 microreactors (SMART=single or multiple addressable radiofrequency tag) [25] (Scheme 12). [Pg.98]

In all cases, previously reported polymer-bound PTCs are ones which contain one PTC site/functionalized arm of polymer. Because of the ability to vary the nature of the substrate introduced onto the polymer arm, the preparation of a polymer-bound PTC with more than one PTC site/ functionalized arm of polymer becomes possible. In theory, then, the number of grams of polymer backbone material needed to carry a particular level of required PTC active-site equivalency would be less for a "multi-site substance compared to previously reported polymer-bound "single-site" PTCs. Similar considerations apply as well to nonpolymeric "multi-site" PTCs derived from simple, polyhalo substrates. Therefore, in general, "multi-site" PTCs offer the potential (1) of providing greater PTC activity on a PTC site/g of PTC needed for catalytic activity basis and (ii) of effecting a particular synthetic transformation under milder and/or more efficient conditions. Thus, economy of scale and efficiency are important considerations for both polymeric and nonpolymeric "multi-site" PTCs. [Pg.170]

Radionuelides can be also used to study the accumulation and degradation of organic pollutants. In our experiments we have followed the uptake and degradation of labelled TNT by wetland plants (Nepovim et al., 2005), and showed that about 63% of the localized in the roots of Ph. australis was bound (Fig. 6) and the remainder was acetone-extractable. An HPLC analysis of the acetone extract failed to detect any TNT, showing that all TNT had been chemically transformed. Thus TNT was not adsorbed on the root surface. In similar experiments performed in wheat (Triticum aestivum). Sens et al. (1999) found that 57% of the taken up was bound... [Pg.146]

However, separation of the carborane cage from The phos-phazene ring or chain by a methylene spacer group allows metals to be Inserted into the open face of the carborane. These syntheses were accomplished by the reaction routes shown in Schemes 3 and A. High polymeric analogues of these transformations have also been accomplished following polymerization of XXX. The rhodium-bound cyclophosphazenes and polyphosphazenes are catalysts for the hydrogenation of 1-hexene. In this, they show a similar behavior to metallocarboranes linked to polystyrene... [Pg.60]


See other pages where Bounded similarity transformations is mentioned: [Pg.88]    [Pg.88]    [Pg.99]    [Pg.481]    [Pg.80]    [Pg.6]    [Pg.143]    [Pg.193]    [Pg.108]    [Pg.439]    [Pg.1348]    [Pg.1349]    [Pg.272]    [Pg.445]    [Pg.667]    [Pg.92]    [Pg.407]    [Pg.8]    [Pg.112]    [Pg.452]    [Pg.70]    [Pg.29]    [Pg.433]    [Pg.217]    [Pg.70]    [Pg.154]    [Pg.172]    [Pg.82]    [Pg.412]    [Pg.611]    [Pg.609]    [Pg.194]    [Pg.2]    [Pg.166]    [Pg.92]    [Pg.136]    [Pg.116]    [Pg.118]   


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Similarity transformation

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