Extraction of NMR spectra and structural data from documents for semantic representation and reuse
For at least fifty years, liquid state Nuclear Magnetic Resonance (NMR) has served as an important analytical technique in studying local atomic bonding information. Thus, a vast amount of data of interest to the chemist and crystallographer resides in archived documents, containing liquid state NMR spectra and accompanying molecular structures. These structures are determined on the basis of chemical shift information from spectra using well established empirical rules. The combined wealth of information represented visually in the spectra and molecules precludes straightforward inclusion in a traditional database. Given its value to the researcher, work by this group is being dedicated to automatic extraction of spectral and molecular information from documents, for conversion to a machine-readable format and incorporation into a database.
Abstract A layer of random defects in the simple cubic Ising model with nearest neighbor ferromagnetic interactions of strength J is considered. Using the real space renormalization group method we calculate defect free energy in the whole temperature range. Specifically, we analyze: the layer of diluted defects, the layer of spin-glass type defects, and the layer of mixed defects. The free energy is strongly dependent on the value of couplings between the defect and the bulk.