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A Further Applications

Expanding Waves. As a further application we tmn to the expanding potential problem [261-263], where we shall work from the amplitude modulus to the phase. The time-dependent potential is of the form... [Pg.126]

As a further application of the reaction, the conversion of an endocyclic double bond to an c.xo-methylene is possible[382]. The epoxidation of an cWo-alkene followed by diethylaluminum amide-mediated isomerization affords the allylic alcohol 583 with an exo double bond[383]. The hydroxy group is eliminated selectively by Pd-catalyzed hydrogenolysis after converting it into allylic formate, yielding the c.ro-methylene compound 584. The conversion of carvone (585) into l,3-disiloxy-4-methylenecyclohexane (586) is an example[382]. [Pg.369]

A further application of the Dieckmann cyclization is that leading to the synthesis of 3,4,6,12-tetrahydro-l(2jE )-indolo[2,3-6]quinolizin-l-one (398). ... [Pg.179]

As a further application of the Wiener-Khinchine theorem, we shall now calculate the power density spectrum of the shot noise process. The autocorrelation function for such a process is given by Campbell s theorem, Eq. (3-262), repeated below... [Pg.185]

Wietek s work has been done on styrene-maleic anhydride. A further application is in recovery of PVC from wiring harnesses. [Pg.95]

A further application of this technology will certainly be the fabrication of membranes of these materials. Membrane reactors have shown great utility in many systems, where one component of a reaction mixture can be separated by permeation through a membrane, thus driving a reaction forwards, by continuous separation. Such continuous processes can themselves save a great deal of waste. [Pg.73]

You and co-workers have demonstrated a further application of NHCs in the kinetic resolution of formyl p-lactams ( )-265 [103]. Upon treatment with a chiral NHC, the Breslow-type intermediate is formed, followed by ring-opening of the P-lactam moiety, with subsequent trapping of the acylazolium intermediate leading to the enantio-enriched succinimide product 266 and resolved formyl P-lactam (which is reduced to its alcohol 267). The authors note that when R" = H, the products undergo racemisation readily, and this is a possible explanation for the lower levels of enantioselectivity observed in the succinimide products 266 (Scheme 12.60). [Pg.294]

A further application of the manipulation of microbial activity in the rhizo-sphere is their potential to remediate contaminated land. Bioremediation involves the u.se of microorganisms that break down contaminants. Radwan et al. (255) found that the soil associated with the roots of plants grown in soil heavily contaminated with oil in Kuwait was free of oil residues, presumably as a result of the ability of the resident rhizosphere microflora to degrade hydrocarbons. The use of plants as a means to accumulate pollutants such as heavy metals (256,257) to degrade hydrocarbons and pesticides (255) is already widely implemented and has proven to be successful. In some cases, there is no doubt that it is the plant itself that is responsible for the removal of the contaminants. However, in most... [Pg.125]

For a further application of the mass balance equation to removal processes, four basic assumptions are made ... [Pg.722]

Methodical details of crystal calculations have been published by several authors (8, 95-98). As applications we only mention the calculation of the crystal structure of diphenyl (98, 99) which has a planar structure in the solid state (100) whereas gaseous diphenyl is twisted around the CC-bond, which links both benzene rings, by about 40° (101). The calculations reproduce satisfactorily the experimental findings. A further application is the calculation of the crystal structures of a series of amides (102), with the object of deriving suitable functions for the description of hydrogen bonds (cf. previous Section). [Pg.200]

A further application of ring-closing metathesis in seven-membered heterocyclic ring formation is in the synthesis of the trans-fused oxpane systems. This process involved tandem RCM/allylstannane-aldehyde cyclizations and interaction of the process provides access to trans-fused polyoxepanes <00S883>. [Pg.352]

A further application of flash photolysis is illustrated by the reactions of a quinone (Q). The kinetic scheme in ethanol (RH) and water is made up of a number of elementary steps, which are given in Figure 10.12. [Pg.190]

In a further application of MI-SPE, theophylline could be separated from the structurally related caffeine by combining the specific extraction with pulsed elution, resulting in sharp baseline-separated peaks, which on the other hand was not possible when a theophylline imprinted polymer was used as stationary phase for HPLC. A detection limit of 120 ng mb1 was obtained, corresponding to a mass detection limit of only 2.4 ng [45]. This combination of techniques was also used for the determination of nicotine in tobacco. Nicotine is the main alkaloid in tobacco and is the focus of intensive HPLC or GC analyses due to its health risk to active and passive consumers. However, HPLC- and GC-techniques are time-consuming as well as expensive, due to the necessary pre-purification steps required because the sample matrices typically contain many other organic compounds besides nicotine. However, a simple pre-concentration step based on MI-SPE did allow faster determination of nicotine in tobacco samples. Mullett et al. obtained a detection limit of 1.8 jig ml 1 and a mass detection limit of 8.45 ng [95]. All these examples demonstrate the high potential of MI-SPE to become a broadly applicable sample pre-purification tool. [Pg.146]

There is a further application of the diagonal elements of the hat-matrix in full CV. By using the values hit from the OLS model estimated with all n objects, one can avoid to estimate OLS models for all subsets of size n — 1, because there exists the relation... [Pg.143]

A further application of direct injection APl-electrospray to the structural elucidation of peptides is to partially fragment the peptide. In this way, one can often determine the partial or complete amino acid sequence of the peptide of interest (Ramstrom et al., 2003). This is particularly useful in rapidly estabhshing amino acid sequences of synthetic peptides in which the confirmation of a sequence can be done in a few moments rather than going through a complex amino acid analysis derived from a sequential hydrolysis process. [Pg.154]

Antibody-directed enzyme prodrug therapy (ADEPT) illustrates a further application of... [Pg.43]

In the following year, Bringmann et al. showed a further application of a biomimetic oxidative coupling of murrayafoline A (7) to the first total synthesis of murrastifoline F (191) (162). This work also includes the resolution of ( + )-murrastifoline F (191), the stereochemical assignment of its atropisomers, and the determination of the enantiomeric ratio present in an authentic root extract of M. homigii. [Pg.296]

Ring-closing metathesis, which has proved to be a popular route to the marine toxins, has found a further application as the key step in the synthesis of the pheromone (-)- and ( )-frontalin <99TL1425>. The precursor in this reaction is a mixture of the syn- and anri-isomers 39. Ring closure in the presence of a ruthenium benzylidene catalyst occurs within minutes at room temperature when only the syn-isomer cyclises to 40. The unreacted anri-isomer can be re-equilibrated for a further cyclisation. [Pg.345]

A further application of the coplanar cell configuration showed in Fig. 3.1(c) concerns the study of the time dependence of the photocurrent following carrier excitation by means of a short pnlse of illnmination. This transient photodecay technique enables the examination of the interaction of initially free carriers with varions localized states. In principle, the decay of photocnrrent measured in this manner should (in the absence of recombination effects and phenomena associated with drift close to the surface of a thin film) correspond to the behavior in the initial pre-transit regime of a TOF pnlse. Becanse it allows measurements to be performed on very thin films under conditions appropriate to their nse in many device applications, and because the photocurrent may be examined over several decades of time withont the complications associated with carrier extraction, the techniqne has become rather popular over recent years. [Pg.41]

The fabrication of active semiconductor devices from amorphous semiconductor films is a further application that offers considerable advantages. Thin-fihn transistors, based on amorphous films of hydrogenated silicon, are nnder intensive development. Other devices with monostable and bistable switching characteristics have also received considerable interest. Naturally enough, the performance of snch devices is intimately related to the transport properties of charge carriers in the materials employed. [Pg.42]

A further application of the isotope dilution technique is the determination of selenomethionine in human blood serum by capillary HPLC-ICP(ORC) MS. [Pg.199]

A further application of relaxation rate measurements is that similar 1/71 ratios in a series of lanthanide complexes may be taken to indicate an isostructural series. However, this approach has the limitation that if only part of the complex is studied, perhaps an organic ligand, its 71 ratios would be independent of changes, for example changes in the extent of hydration in the remainder of the complex, provided that the conformation of the ligand relative to the lanthanide ion were preserved. An excellent example of the use of 71 data in a quite different way is its use to determine hydration numbers of lanthanide dipicolinate complexes.562... [Pg.1103]

Dissociation of the dimer means the rupture of two hydrogen bonds. The bonding energy of the single O-H O bond in this case is about 33 kJ moh1 (7.5 kcal/mole). A further application of elementary thermodynamics to these data tells us that the entropy change on dissociation is AS e = 76 J moh1 Kh1, a result that is... [Pg.15]


See other pages where A Further Applications is mentioned: [Pg.304]    [Pg.118]    [Pg.19]    [Pg.882]    [Pg.299]    [Pg.516]    [Pg.36]    [Pg.69]    [Pg.28]    [Pg.345]    [Pg.272]    [Pg.325]    [Pg.370]    [Pg.172]    [Pg.594]    [Pg.210]    [Pg.92]    [Pg.530]    [Pg.792]    [Pg.59]    [Pg.265]    [Pg.86]    [Pg.187]    [Pg.405]    [Pg.552]    [Pg.295]   


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Further applications

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