Some Outstanding Chemical Problems

The department at K.U. since 1948, when Stanley Walas joined the staff, has been fortunate to always have a person teaching design who has up-to- date-industrial design experience. Walas has been followed by Swift and in turn by Howat as design instructors. Not many chemical engineering departments have had such qualified persons. The competencies of these men have resulted in the development of some outstanding performers in solving the student contest problem. 

Alumina is one of the most widely used multipurpose ceramics. It is essentially used in orthopedics for its good tribological properties and its outstanding chemical inertia. One of the advantages of alumina is that it is a very bad substrate for the crystalline growth of calcium phosphates, which can alter other friction couples [ROY 93]. It constitutes the heads of femoral prostheses and is used also in the development of the acetabulum. Early applications raised some problems of... 

There are of course methods which attempt to tackle these problems in their complexity, and avoid some of the approximations we have described we quote, as an outstanding example, the Car-Parrinello approach (Car and Parrinello, 1985), that in recent extensions has aimed to give a coherent QM description of such models (Laasonen et al., 1993 Fois et al., 1994). However, these approaches are still in their infancy, and it is advisable to look at other models for liquids and chemical reactions in solutions. 

Enzymes have many potential advantages when used as catalysts for chemical synthesis. The unique properties offered by these biocatalysts are, first of all, their often outstanding chemo-, regio-, and, in particular, stereoselectivity. Furthermore, enzymes are highly efEcient catalysts working under very mild conditions. However, enzymes do also have some drawbacks that may limit their potential use, such as ability to accept a limited substrate pool only, and a moderate operational stability. Ways of overcoming most of these potential limitations exist and they pose in most cases more of a perceived than a real problem. Well over 100 different biocatalytic processes have been implemented on an industrial scale [1]. A few processes are... 

The chemical aspects of coumarin chemistry have recently been comprehensively summarized. In view of the availability of this treatise it appears useful here to focus on some special topics in coumarin chemistry where outstanding problems remain in an attempt to identify those research areas which might benefit by further work. 

Coming to the end, an attentive and informed reader may have observed that the solved problems that we have selected belong to a special group of research papers that have received limited acknowledgment, at least as reflected in their limited citations. This does not mean necessarily that a limited number of researchers have seen them and have been aware of some of them, which could be the case had they been published in some obscure scientihc journals. Because they have been published in outstanding journals, such as the Journal of the American Chemical Society, Tetrahedron, Journal of Physical Chemistry, Journal of Chemical Information and Computer Science, International Journal of Quantum Chemistry, Chemical Physics Letters, Journal of Computational Chemistry, New Journal of Chemistry, Journal of Mathematical Chemistry, SAP and QSAR in Environmental Research, Journal of Molecular Graphics and Modelling, and such, it is fair to assume that these papers may have been seen but, in view of their limited citations, tend to be avoided. 

---