196,298 research outputs found
La Regione Vulcanica dei Colli Albani.Vulcuno Laziale. de M. Fornaseri, U. Ventriglia. A. Scherillo
No full textKieffer Guy. La Regione Vulcanica dei Colli Albani.Vulcuno Laziale. de M. Fornaseri, U. Ventriglia. A. Scherillo. In: Annales de Géographie, t. 75, n°412, 1966. pp. 728-731
Contributi alla storia del libretto d\'opera. \'L\'opera buffa napoletana\' di M. Scherillo
No full textMichele Scherillo studioso dell'opera buffa napoletan
Contributi alla storia del libretto d\'opera. \'L\'opera buffa napoletana\' di M. Scherillo
No full textMichele Scherillo studioso dell'opera buffa napoletan
An information filtering system for e-health: the health-on-net experience
No full textThis paper describes a work performed in the framework of the HealthOnNet project purposed to define and implement an Internet-based repository of diagnostic exams and medical reports connecting several Italian hospitals. The repository, which will be used as an historical and legal archive of clinical data, offers second opinion teleconsulting features as well as advanced categorization and filtering services. The paper is focused on this latter point and describes the process and the algorithms we defined to automatically classify medical documents (with respect to the widely adopted International Classification of Diseases and Related Health Problems of the World Health Organization) and to filter them on the basis of a user defined profile. Then it describes the developed prototype and some experimentation results
Time-Resolved Fourier Transform Infrared Spectroscopy, Gravimetry, and Thermodynamic Modeling for a Molecular Level Description of Water Sorption in Poly(epsilon-caprolactone)
No full textSorption of water in poly(eps-caprolactone) (PCL), with specific focus on the hydrogen-bonding interactions, has been analyzed by combining ab initio calculations, macroscopic thermodynamics modeling, and relevant features emerging from spectroscopic and gravimetric measurements. Fourier transform infrared (FTIR) data, analyzed by difference spectroscopy, two-dimensional correlation spectroscopy, and least-squares curve-fitting analysis associated with gravimetric determination of water sorption isotherm provided information on the system's behavior and on the molecular interactions established between the polymer and the penetrant. A consistent physical picture emerged pointing to the presence of two spectroscopically discernible water species (first-shell and second-shell layers) that have been quantified. Water molecules are present in the form of dimers within the polymer equilibrated with water vapor up to a relative humidity of 0.65. At higher humidities, clustering of water sorbed molecules starts to take place. The multicomponent nu(OH) band representative of absorbed water has been interpreted with the aid of ab initio calculations performed on suitably chosen model systems. The outcomes of spectroscopic analyses were interpreted at a macroscopic level by modeling the thermodynamics of water sorption in PCL based on a nonrandom compressible lattice theory accounting for hydrogen-bonding (HB) interactions. Starting from the fitting of the gravimetric sorption isotherm, the model provided quantitative estimates for the amount of self- and cross-HBs which compare favorably with the FTIR results
Finite element modeling of superplastic forming of friction stir processed AZ31B mg alloy
No full textSuperplastic forming (SPF) is considered to be a near net shape manufacturing technique, mainly adopted to realize aircraft and automotive parts, which requires relatively high tooling and assembly costs. Furthermore the tuning of the process is a non trivial operation since very limited reliable models have been developed to predict the complex geometries obtained through SPF. In such context several researches, based on finite element method (FEM,) have been conducted on the numerical optimization of conventional SPF processes. Friction Stir Processing (FSP) can be used combined with conventional SPF to enhance the superplastic material behavior by means of grain refinement treatment locally performed. From this point of view very few models have been developed to simulate the different superplastic behavior distinguishing the materials after the application of FSP. In this work free bulge forming tests of AZ31B Mg alloy was experimentally performed by means of blow forming laboratory-scale equipment as well as FEM analysis were conducted to simulate the SPF in two different cases: unprocessed and friction stir processed (FSProcessed) condition. The most relevant parameters of the constitutive numerical model were optimized by numerical-experimental comparison. More specifically material strength factor (K) and strain rate sensitivity index (m) were considered during the parametric optimization. Strain and thickness distributions were compared to the experimental measurements in order to individuate the optimized constitutive equations governing the superplastic behavior in both case studies
Probing effect of solvent concentration on glass transition and sub-Tg structural relaxation in polymer solvent mixtures: The case of polystyrene-toluene system
No full textA novel experimental method for the analysis of volume relaxation induced by solvents in glassy polymers is presented. A gravimetric technique is used to evaluate the isothermal solvent mass uptake at controlled increasing/decreasing solvent pressure at constant rate. Fundamental properties of the solvent/polymer system can be obtained directly, and models can be applied, combining both nonequilibrium thermodynamics and mechanics of volume relaxation contribution. The fundamental case of polystyrene and toluene mixtures are thus accounted for, and various experimental conditions have been explored, varying the temperature, and spanning over different pressure increase/decrease rates. The results obtained allowed to evaluate the isothermal second order transition induced by solvent sorption, as well as the determination of the effect of the pressure rate. Therefore, this work proposes a new standard for the characterization and the understanding of the relaxational behavior of glassy polymers
Transport Properties of Zeolite Na-X-Nafion Membranes: Effect of Zeolite Loadings and Particle Size
No full textNa-X zeolites particles, synthesized in two size ranges,
namely 200–300 nm and 30–100 nm, were used to prepare
Nafion/Na-X zeolite composite membranes by recast
method. The physical, chemical, and morphological properties
of the zeolite powders and composite membranes were
examined by XRD, N2 adsorption isotherms, FTIR, SEM,
and SAXS analysis. Furthermore, the effect of zeolite particles
size and loadings (i.e., 5 and 10% w/w) on the water,
methanol, and proton transport properties was investigated.
It has been found that the size of the Na-X zeolite particles
plays a key role in the proton and methanol transport
behavior since it rules the zeolite hydrophilic behavior, the
morphology of polymer–filler interphase, and also the nature
of water established in the composite membrane.
The results show that the membranes loaded with a 5%
w/w of submicron-sized Na-X zeolite exhibit a proton conductivity
and selectivity significantly higher than Nafion. In
particular the proton conductivity at 120 °C is around eight
times and the selectivity at 25 °C is around 40% higher than
those exhibited by recast Nafion
Water sorption thermodynamics and mass transport in PCL: interactional issues emerging from vibrational spectroscopy
No full textIn this work, FTIR spectroscopy in transmission mode has been used to study the water sorption and transport in poly--caprolactone (PCL). The characteristic spectrum of absorbed water was isolated data by using difference spectroscopy, to obtain a description of the water sorption mechanism at a molecular level. Moreover, spectroscopic data were coupled with gravimetric sorption measurements, to correlate the equilibrium absorbance with water concentration in PCL.
The transient sorption stage was also analysed, allowing an estimation of water diffusion coefficient in PCL.
The analysis of the spectral region of the (OH) stretching vibration of water revealed the presence of two species of absorbed water, i.e. water molecules directly interacting with carbonyl group of polymer backbone and dimers, corresponding to a second shell hydration layer. Finally, the experimental sorption isotherms were successfully interpreted using an equation of state thermodynamic approach grounded on a compressible lattice fluid framework accounting for self- and cross-hydrogen bond formation. Based on the evidences of the FTIR spectroscopy, in the implementation of the model, only one proton acceptor group (i.e. carbonyl) has been assumed to be present on the polymer backbone
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