Search results for "reflection"
showing 10 items of 645 documents
Tommaso Maria Napoli Utriusque Architecturae Compendium Roma 1688 Breve trattato sulle fabbriche civili e militari e la conservazione delle architett…
2013
Il volume Tommaso Maria Napoli Utriusque Architecturae Compendium Roma 1688 Breve trattato sulle fabbriche civili e militari e la conservazione delle architetture del frate domenicano Tommaso Maria Napoli, vuole contribuire ad accrescere le nostre conoscenze sui principi che dovevano sottendere alla realizzazione dell’architettura civile e militare del periodo barocco e tardo barocco, così come espressi nel breve trattato scritto dal frate architetto, nato a Palermo, Tommaso Maria Napoli (1659-1725), e pubblicato a Roma alla fine del Seicento. Alla traduzione dal latino del trattato, redatta da esperti (Fabio Zarbo e Pietro Zarbo), è inclusa un’interessante ricerca, redatta congiuntamente c…
Surface plasmon interference fringes in back-reflection
2010
We report the experimental observation of surface plasmon polariton (SPP) interference fringes with near-unity visibility and half-wavelength periodicity obtained in back reflection on a Bragg mirror. The presented method based on leakage radiation microscopy (LRM) represents an alternative solution to optical near-field analysis and opens new ways for the quantitative analysis of SPP fringes. With LRM we investigate various SPP interference patterns and analyze the high reflectivity of Bragg mirror in comparison with theoretical models.
A tris-oxovanadium pyrogallate complex: synthesis, structure, and magnetic and electronic properties
2021
International audience; With the aim of identifying new cation-phenolate complexes, we herein investigated the reactivity of pyrogallol (H(3)pgal) with vanadium salts. A trimetallic anionic complex was identified, and found to be formed under a broad set of reaction conditions. This complex, with the formula V3O3(pgal)(3)(3-), consists of three oxovanadium(iv) units connected together by three pyrogallate ligands to afford a bowl-shaped species presenting a pseudo 3-fold symmetry axis. Its crystal structure is reported, as well as its characterisation by a broad set of techniques, including powder X-ray diffraction, thermogravimetric analysis, infrared and Raman spectroscopy, and solid stat…
Nanocomposites of bacterial cellulose/hydroxyapatite for biomedical applications.
2008
In the present work, a nanocomposite material formed by bacterial cellulose (BC) networks and calcium-deficient hydroxyapatite (HAp) powders was synthesized and characterized. The HAp nanoparticles were previously prepared by a wet chemical precipitation method, starting from aqueous solutions of calcium nitrate and di-ammonium phosphate salts. Energy-dispersive spectroscopy reveals that the prepared HAp corresponds to calcium-deficient hydroxyapatite. BC-HAp nanocomposites were prepared by introducing carboxymethylcellulose (CMC) into the bacteria culture media. HAp nanoparticles were then introduced and remained suspended in the culture medium during the formation of cellulose nanofibrils…
Qualità della didattica universitaria e sviluppo della capacità decisionale. Il modello ADVP per garantire i passaggi da L-19 a LM-85bis.
2020
Il presente contributo intende offrire una riflessione sulle competenze attese individuate attraverso la formulazione dei descrittori di Dublino dei CdS in Scienze dell’Educazione (L-19) e Scienze della Formazione Primaria (LM-85bis) istituiti presso l’Ateneo di Palermo e nello stesso tempo proporre un modello per lo sviluppo della maturità professional e necessaria a garantire scelte consapevoli, mature e responsabili. L’analisi condotta ci ha permesso, in una seconda fase di individuare gli obiettivi formativi finali scelti seguendo il modello proposto dalle Linee Guida dell ’Anvur, e di scegliere il modello dell’Activaction du Developpement Vocationnel et Personnel quale strumento per lo…
<title>Electronic eye occluder with time-counting and reflection control</title>
2008
ABSTRACT In pediatric ophthalmology 2 3 % of all the children are impacted by a visual pathology amblyopia. It develops if a clear image isnt presented to the retina during an early stage of the developmen t of the visual system. A common way of treating this pathology is to cover the better-seeing eye to force the lazy eye to learn seeing. However, children are often reluctant to wear such an occluder because they are as hamed or simply because they find it inconvenient. This fact requires to find a way how to track the regi me of occlusion because results of occlus ion is a hint that the actual regime of occlusion isnt that what the optometrist has recommended. We design an electr…
Binding, Interaction, and Organization of Proteins with Lipid Model Membranes
1991
Model membrane systems are used to investigate protein recognition and binding at interfaces. Fluorescence microscopy results are presented for interactions of the proteins, phospholipase A2 and antifluorescyl IgG, at lipid monolayer interfaces. Total internal reflection fluorescence measurements are used to quantify albumin and IgG adsorption to supported lipid monolayers.
EFFECTS OF THE MULTIPLE INTERNAL REFLECTION AND SAMPLE THICKNESS CHANGES ON DETERMINATION OF ELECTRO-OPTIC COEFFICIENT VALUES OF A POLYMER FILM
2012
New nonlinear optical (NLO) active organic materials are appealing candidates for optoelectronic and photonic technologies. For the evaluation of new NLO polymer materials for applicability in the mentioned technologies, the most important criteria are their electro-optic (EO) coefficients. We have implemented the Mach–Zehnder interferometric (MZI) method for the determination of EO coefficients of thin organic films. Despite the fact that other multiple optical methods for the determination of thin film EO coefficients are known, the MZI method has been chosen because this particular technique has high sensitivity to phase and intensity modulations in the sample arm of an interferometer an…
Whispering gallery mode resonator sensors referenced to saturated absorption lines in rubidium atoms and a fs frequency comb
2019
Optical Whispering Gallery Mode Resonators (WGMR) can be produced by many methods, for example, by flame melting of silica fibers [1], by polishing of crystals [2], by optical lithography, by solidifying transparent materials, or using commercially available microspheres. They confine light by the total internal reflection and do not need mirror coatings. A part of radiation is traveling outside the WGMR as an evanescent wave and it is used for sensing applications. WGMRs are becoming increasingly popular as biosensors [3] when their surface is covered with antibodies to provide selectivity. Advantage is that light circulates in the resonator and interacts many times with a few molecules at…
Tuneable multicoloured patterns from photonic cross-communication between cholesteric liquid crystal droplets
2014
Monodisperse droplets of planar-aligned cholesteric (N*) liquid crystal exhibit an intriguing capacity for photonic cross-communication, giving rise to colourful patterns that depend sensitively on the N* pitch, droplet positions and illuminated area. The phenomenon results from a combination of omnidirectional selective reflection of N* droplets—which thus act as spherically symmetric self-assembled photonic crystals—and total internal reflection at the continuous phase surface. We outline how the unique optical properties can be employed in numerous applications.