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be computed through publicly available information. The article describes an approach for benchmarking using these performance measures and demonstrates how meaningful results may be derived from this exercise. By following this framework, a firm can identify areas of opportunity for improvement in its internal supply chain. Further, the framework can help to identify specific reasons behind the performance levels in the internal supply chain and stimulate performance improvement. To illustrate the framework, it is applied to the paint industry. The framework provides meaningful results for the firms in the industry.

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We give explicit construction of vertex-transitive tight triangulations of d-manifolds for d ≥ 2. More explicitly, for each d ≥ 2, we construct two (d 2 + 5d + 5)-vertex neighborly triangulated d-manifolds whose vertex-links are stacked spheres. The only other non-trivial series of such tight triangulated manifolds currently known is the series of non-simply connected triangulated d-manifolds with 2d + 3 vertices constructed by Kühnel. The manifolds we construct are strongly minimal. For d ≥ 3, they are also tight neighborly as defined by Lutz, Sulanke and Swartz. Like Kühnel's complexes, our manifolds are orientable in even dimensions and non-orientable in odd dimensions.MSC 2000 : 57Q15, 57R05.

Noncovalent interactions that are selective, directional, and strongly attractive can induce the self-assembly of predictable su-pramolecular aggregates. Tectons (from Greek, tekton, builder) of selected local symmetry, length and flexibility are used as simple assembly blocs of Lego type for construction of specialized networks. Several diamantoid networks were crystallized and studied by X-ray diffraction technique in order to verify the self-assembling properties of those novel tectons. These structures have in common the fonnation of large chambers whose size and shape follow directly from that of the tecton subunits. The network's large cavities so obtained use self-filling by mutual concatenation of similar networks to minimized the empty space in these structures. Besides the large chan1bers, large channels remain occupied by solvent molecules. Novel types of networks, derived from the dian1antoid type, were also characterized. Several new two-and three-dimensional networks were crystallized by using tectonic subunits of locally different primary symmetry. By modification of the flexibility and/or the tenninal group of the arms, new network types were promoted. This communication will present an overview of the subject as well as our most recent works in this area. Several years ago a series of dihydroxitetraalkyldisiloxanes has been studied by physical methods in order to find the structure-property relations for these compounds, which fom1 termothropic liquid crystalline phases. It was found that liquid crystalline properties are due to the formation of one-dimensional columnar hydrogen bonded associates in crystal and mesophase. These associates have pseudohexagonal packing in crystal and fonn mesophase with hexagonal type of columnar packing. In order to find other compounds inclined to form mesophases of the same type we performed conformational calculations and molecular modeling of molecular associates of dihydroxycarbosilanes and dihydroxydisiltianes. It was shown that conformational properties and associate formation for dihydroxycarbosilanes and dihydroxidisiloxanes is very close, but they are not the same for dihydroxydisiltianes. To support the close supramolecular structure of siloxane and carbosilane derivatives crystallization and X-ray analysis of dihydroxitetra-methyldicarbosalan was performed. The one-dimensional columnar associate in this crystal was found to be nearly the same as for disiloxane. DSC and multitemperature powder X-ray data are discussed together with the data on single crystal structure. PS06.05.10 X-RAY AND NEUTRON DIFFRACTION STUDY OF A CROWN ETHER-A CAUTIONARY TALE. R.H. Fenn, University of Portsmouth, S.A. Mason, ILL Grenoble, R.A. Palmer and B. Potter, Birkbeck College, London, O.S. Mills, P.M. Robinson and C. I. F. Watt, University of Manchester, UK Beware all Ye who regard a diffractometer as a black box and do not appreciate the beauty of crystallography. The compound C24H3o06.H20 is a water-bound adduct of the tetragol crown ether 9,10-dihydro,-10,10-dimethyl,-9...

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