Network characterization procedure

The history of dendrimer chemistry can be traced to the foundations laid down by Flory [34] over fifty years ago, particularly his studies concerning macro-molecular networks and branched polymers. More than two decades after Flory s initial groundwork (1978) Vogtle et al. [28] reported the synthesis and characterization of the first example of a cascade molecule. Michael-type addition of a primary amine to acrylonitrile (the linear monomer) afforded a tertiary amine with two arms. Subsequent reduction of the nitriles afforded a new diamine, which, upon repetition of this simple synthetic sequence, provided the desired tetraamine (1, Fig. 2) thus the advent of the iterative synthetic process and the construction of branched macromolecular architectures was at hand. Further growth of Vogtle s original dendrimer was impeded due to difficulties associated with nitrile reduction, which was later circumvented [35, 36]. This procedure eventually led to DSM s commercially available polypropylene imine) dendrimers. 

Fredericks et al. (1985) describe materials characterization by factor analysis of IR spectra . Wold et al. (1987) the principal component analysis , and Haaland and Thomas (1988) materials characterization using factor analyses of FT-IR spectra . Of special importance are the procedures using fuzzy logic and neural networks (Harrington, 1991 Zupan and Gasteiger, 1993). 

Regarding procedures for characterization of waste, harmonization on various objectives and leaching/extraction test methods is undertaken by European Standardization Network CEN, Technical Committee (TC) 292, and a distinction is made between three types of leaching tests which will be applied in different circumstances (Van der Sloot et al. 1997, Van der Sloot 1998, 2002) ... 

Thermal analysis measurements via DSC were utilized both to follow the curing reaction and to characterize the precursor and network materials. The general techniques for following reactions by differential scanning calorimetry are well established and can be reviewed in reference 15. We have also discussed the procedures for this type of an experiment in one of our earlier publications (16). A Perkin-Elmer Model 2 instrument was utilized. 

The trend for companies to focus on core competencies has forced enterprises to collaborate closely with their suppliers as well as with their customers to improve business performance (Lutz et al. 1999). The next step in the supply chain concept is the production or supply networks (Figure 15), which are characterized by intensive communication between the partners. TTie aim of the system is to allocate among the collaborating partners the excess in production demand that could not be faced by one of them alone. This capability provides the entire network with the necessary flexibility to respond quickly to peaks in demand for the products. A tool developed at the Institute of Production Systems at Hanover University, the FAS/net, employs basic methods of production logistics to provide procedures for the efficient use of capacity redundancies in a production network. The tool satisfies the following requirements derived from the capacity subcontracting process ... 

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