Search results for "Sauer"
showing 6 items of 16 documents
Validation of the mass response of a quartz crystal microbalance coated with Prussian Blue film for ac electrogravimetry
2000
Prussian Blue (PB) films have been considerably studied for many research applications such as electrochromic material development, new material for batteries, etc. Many analytical techniques were employed for examining PB electrochemical behaviour in solution and the quartz crystal microbalance (QCM) used in the alternative regime (ac electrogravimetry) appeared as an attractive in situ mass sensor due to its low cost and its high mass sensitivity. Unfortunately, the validity of the common Sauerbrey equation was questionable with these films or in other terms if the QCM was used as a pure mass sensor. In this work PB film is examined through acoustic measurements and the response can be in…
Carl Ortwin Sauer e la geografia culturale contemporanea
2011
Il contributo intende focalizzare l'attenzione sul lavoro di Carl Ortwin Sauer, padre della moderna Geografia Culturale, poco studiato in Italia.
Carl Sauer e gli ultimi lavori sul continente americano. The Early Spanish Main
2014
Carl Ortwin Sauer (1889-1975), capostipite della Scuola di Berkeley, è da molti considerato il padre fondatore della geografia culturale contemporanea, ma la sua opera complessiva è generalmente poco conosciuta in Italia. Il geografo americano è noto alla comunità scientifica internazionale per aver scritto nel 1925 il saggio “The Morphology of Landscape”, che individua chiaramente una nuova strada metodologica da seguire in Geografia. Obiettivo del presente lavoro è di focalizzare l’attenzione sull’interessante produzione degli ultimi anni di vita del geografo. In particolare si discuterà del lungo lavoro di ricerca e della metodologia utilizzata per le analisi del continente americano ai …
Density functional theory study of the mechanism of the proline-catalyzed intermolecular aldol reaction
2002
Transition structures associated with the C-C bond-formation step of the proline-catalyzed intermolecular aldol reaction between acetone and isobutyraldehyde have been studies using density functional theory methods at the B3LYP/6-31G** computational level. A continuum model has been selected to represent solvent effects. For this step, which is the stereocontrolling and rate-determining step, four reactive channels corresponding to the syn and anti arrangement of the active methylene of the enamine relative to the carboxylic acid group of l-proline and the re and si attack modes to both faces of the aldehyde carbonyl group have been analyzed. The B3LYP/6-31G** energies are in good agreemen…