Search

Your search keyword '"Huvenne, J."' showing total 113 results
Start Over Author "Huvenne, J."
113 results on '"Huvenne, J."'

31. Preparation and physical characterization of forms II and III of paracetamol.

Author

Martino, P., Conflant, P., Drache, M., Huvenne, J., and Guyot-Hermann, A.

Abstract

The polymorphic forms II and III of paracetamol were obtained by melting the marketed form I. Under the melting and cooling conditions used, it was possible to obtain forms I, II and III. The recrystallization conditions and the physical properties of forms II and III were investigated by means of various techniques: thermomicroscopy, DSC analysis, infrared microspectrometry and X-ray powder diffraction at room temperature and as a function of temperature. Form III was found to be very unstable. However, its formation seems to be an important intermediate step in the preparation of form II. [ABSTRACT FROM AUTHOR]

Published
1997
Full Text
View/download PDF

38. Hierarchical Neural Network Modeling for Infrared Spectra Interpretation of Modified Starches

Author

Dolmatova, L., Tchistiakov, V., Ruckebusch, C., Dupuy, N., Huvenne, J.-P., and Legrand, P.

Abstract

The goal of this research was to demonstrate a new approach to multilevel hierarchical modeling using neural networks. In a situation where the data set is small and error-prone, it is necessary to build multiple models of input−output relationships, combining these models into a hierarchical structure. This allows utilization of the best aspects of every model, eliminating the need to choose “the best one”, when the general sample itself is not known exactly. At the first stage of modeling we used feed-forward artificial neural networks for spectra interpretation. Then at the second stage a simultaneous recurrent network was used to correct the predictions made at the first stage. This architecture enables enhancement of the generalization ability according to the similarity of the input patterns. The suggested method was applied to the interpretation of spectra of modified starches. This has definite practical value, since authentication of food is very important for the consumers and the food industry at each level of the food chain from raw materials to finished products. It is demonstrated that multilevel modeling offers accuracy advantages compared to choosing the best model or model averaging.

Published
1999

49. Bovine elastin and kappa-elastin secondary structure determination by optical spectroscopies.

Author

Debelle, L, Alix, A J, Jacob, M P, Huvenne, J P, Berjot, M, Sombret, B, and Legrand, P

Abstract

Elastin is the macromolecular polymer of tropoelastin molecules responsible for the elastic properties of tissues. The understanding of its specific elasticity is uncertain because its structure is still unknown. Here, we report the first experimental quantitative determination of bovine elastin secondary structures as well as those of its corresponding soluble kappa-elastin. Using circular dichroism and Fourier transform infrared and near infrared Fourier transform Raman spectroscopic data, we estimated the secondary structure contents of elastin to be approximately 10% alpha-helices, approximately 45% beta-sheets, and approximately 45% undefined conformations. These values were very close to those we had previously determined for the free monomeric tropoelastin molecule, suggesting thus that elastin would be constituted of a closely packed assembly of globular beta structural class tropoelastin molecules cross-linked to form the elastic network (liquid drop model of elastin architecture). The presence of a strong hydration shell is demonstrated for elastin, and its possible contribution to elasticity is discussed.

Published
1995

Catalog

Books, media, physical & digital resources
See catalog results