Future developments Number

In dealing with future uncertainties. Royal Dutch/SheU pioneered Scenario planning (54,55). Alternative assumptions for future developments can be combined under this approach in various ways to give a number of consistent possible outcomes (56) and provide a basis for both actions and reactions. The approach has rewarded Shell handsomely. 

SIMS is one of the most powerful surface and microanalytical techniques for materials characterization. It is primarily used in the analysis of semiconductors, as well as for metallurgical, and geological materials. The advent of a growing number of standards for SIMS has gready enhanced the quantitative accuracy and reliability of the technique in these areas. Future development is expected in the area of small spot analysis, implementation of post-sputtering ionization to SIMS (see the articles on SALI and SNMS), and newer areas of application, such as ceramics, polymers, and biological and pharmaceutical materials. 

Whilst the development of flame retarders has in the past been largely based on a systematic trial-and-error basis, future developments will depend more and more on a fuller understanding of the processes of polymer combustion. This is a complex process but a number of stages are now generally recognised and were discussed in Chapter 5. 

In this book we have decided to concentrate on purely synthetic applications of ionic liquids, just to keep the amount of material to a manageable level. FFowever, we think that synthetic and non-synthetic applications (and the people doing research in these areas) should not be treated separately for a number of reasons. Each area can profit from developments made in the other field, especially concerning the availability of physicochemical data and practical experience of development of technical processes using ionic liquids. In fact, in all production-scale chemical reactions some typically non-synthetic aspects (such as the heat capacity of the ionic liquid or product extraction from the ionic catalyst layer) have to be considered anyway. The most important reason for close collaboration by synthetic and non-synthetic scientists in the field of ionic liquid research is, however, the fact that in both areas an increase in the understanding of the ionic liquid material is the key factor for successful future development. 

From these studies it is clear that the progression of PAR-based therapy relies upon the future development of new specific agonists and antagonists for PARs 2-4 with much higher potencies than those currently available, with an efficient mode of delivery to target sites. However despite these problems the PARs still rqiresent one of the most attractive therapeutic targets for a number of disease states. 

According to Galilei, the observation of natural phenomena using suitable measuring instruments provides certain numerical values which must be related to one another the solution of the equations derived from the numbers allows us to forecast future developments. This led to the misunderstanding that knowledge could only be obtained in such a manner. The result was deterministic belief, which was disproved for microscopic objects by Heisenberg s uncertainty principle. On the macroscopic scale, however, it appeared that the deterministic approach was still valid. Determinism was only finally buried when deterministic chaos was discovered. 

The examples discussed in this section provide encouraging leads for the future development of DCLs. Since a large number of biologically relevant substrates (and receptors) involve hydrogen bonding, it is certain that more templates using such interactions to amplify the formation of specific compounds from a dynamic library, will be developed in the future. 

Chemical modification of surface residues of HRP is one method which may offer some improvement in thermal or long-term stability of the enzyme. The -amino groups of the six surface Lys residues can be modified by reaction with carboxylic anhydrides and picryl sulfonic acid (296). In this example the number of sites modified was found to be more significant than the chemical nature of the modification, at least as a criterion for improved stability. Other methods explored include the use of bifunctional crosslinking reagents to couple surface sites on the enzyme (297). Future developments are likely to be concerned with the selection of site-directed mutants of HRP C that show enhanced thermal stability. Dramatic increases in thermal stability of up to 190-fold have been reported recently for mutants of Coprinus cinereus peroxidase (CIP) generated using a directed evolution approach (298). 

In the 1970s the future looked particularly rosy for developers of robotic systems. With hindsight it is clear that this was because something new really stimulates the users of automation their enthusiasm has not been rewarded with the introduction of a vast number of robotic solutions to automatic problems. Indeed, the thinking now is away from the use of complicated robotic systems to more simple, uniformly usable systems. In this chapter a number of robotic systems will be reviewed and a path for future developments set out for the reader to ponder. 

The ability to produce 1,3-dipoles, through the rhodium-catalyzed decomposition of diazo carbonyl compounds, provides unique opportunities for the accomplishment of a variety of cycloaddition reactions, in both an intra- and intermolecular sense. These transformations are often highly regio- and diastereoselective, making them extremely powerful tools for synthetic chemistry. This is exemplified in the number of applications of this chemistry to the construction of heterocyclic and natural-product ring systems. Future developments are likely to focus on the enantioselective and combinatorial variants of these reactions. 

A number of different methods have been proposed to introduce a self-interaction correction into the Kohn-Sham formalism (Perdew and Zunger 1981 KUmmel and Perdew 2003 Grafenstein, Kraka, and Cremer 2004). This correction is particularly useful in situations with odd numbers of electrons distributed over more than one atom, e.g., in transition-state structures (Patchkovskii and Ziegler 2002). Unfortunately, the correction introduces an additional level of self-consistency into the KS SCF process because it depends on the KS orbitals, and it tends to be difficult and time-consuming to converge the relevant equations. However, future developments in non-local correlation functionals may be able to correct for self-interaction error in a more efficient manner. 

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