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A novel two-step procedure involving the formation of 1-arylidene-2-tetralones from 2-tetralone and subsequent Michael addition of a cyclic secondary amine on the alkenone followed by in situ aerial oxidation was developed to produce 2-naphthol Mannich bases. A simple microwave-assisted one-pot synthesis of 2-naphthol Mannich bases was also carried out under solvent-free conditions from 2-naphthol and corresponding aldehydes and amines in the presence of p-toluenesulfonic acid. The compounds of this series displayed interesting NMR behaviour. Extensive variabletemperature NMR investigations, including HSQC experiments, are herein reported. NMR results on the conformation in solution phase were found to be consistent with the X-ray crystal structure in the solid state.Résumé : On a mis au point une nouvelle méthode en deux étapes qui permet de produire des bases de Mannich du 2-naphtol et qui implique la formation de 1-arylidène-2-tétralones à partir de la 2-tétralone, puis une addition subséquente de Michael d'une amine secondaire cyclique sur l'alcénone, suivie d'une oxydation in situ par de l'air. On a aussi réa-lisé une synthèse des bases de Mannich du 2-naphtol par une simple réaction monotope du 2-naphtol, des aldéhydes et des amines correspondants en présence d'acide p-toluènesulfonique, sous l'effet de micro-ondes, dans des conditions sans solvant. Les composés de cette série présentent des comportements RMN intéressants. On a effectué de nombreuses études RMN à température variable, y compris des expériences de « HSQC ». On a trouvé que les résultats de la RMN sur la conformation en solution sont en accord avec la structure cristalline déterminée par diffraction des rayons X, à l'état solide.Mots clés : bases de Mannich, réaction de Mannich assistée par les micro-ondes, spectroscopie RMN à température variable, dynamique RMN, cristallographie par diffraction des rayons X.[Traduit par la Rédaction] Jha et al. 853

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An attempt is made to analyse the lattice thermal conductivity of solid argon at low temperatures, using Holland's model. The dispersion relation q = C sin-' (w/wmax), for transverse phonom, is used to determine vg/vi in the conductivity integrals. A fairly good agreement is obtained between the calculated and the experimental results of Clayton and Batchelder, in the temperature range 1.5 to 20 K. The dislocation density and the average grain size of the polycrystalline specimen are determined to be 2.5 x 10" m-2 and 0.05 mm, respectively.

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a-Fe203 films were prepared by sol-spinning process using ferric nitrate as a precursor and 2-methoxy ethanol as the solvent. The films were grown on various substrates by spin coating and were subjected to different annealing temperatures. These were characterized using X-ray and fourier transform infrared spectroscopy (FTIR). The films showed crystallinity at about 500°C. The surface morphology of these films was studied using scanning electron microscopy (SEM) which revealed cracks for films having thickness of the order of 2gin. The band gap of these films was observed to be 2.1 eV from UV-vis spectroscopy.