Carbon nanohorn-based nanofluids: characterization of the spectral scattering albedo

The full characterization of the optical properties of nanofluids consisting of single-wall carbon nanohorns of different morphologies in aqueous suspensions is carried out using a novel spectrophotometric technique. Information on the nanofluid scattering and absorption spectral characteristics is obtained by analyzing the data within the single scattering theory and validating the method by comparison with previous monochromatic measurements performed with a different technique. The high absorption coefficient measured joint to the very low scattering albedo opens promising application perspectives for single-wall carbon nanohorn-based fluid or solid suspensions. The proposed approximate approach can be extended also to other low-scattering turbid media.     

Intramolecular Charge Transfer Complexes, 29. Morphological Study of Multicomponent Systems

The morphologies formed in poly[β-(N-carbazolyl)ethylacrylate-co-β-(metacryloyloxy) ethyl-3,5-dinitrobenzoate] [poiy(HECA-co-DNBM)] and in its triblock copolymer with poly(N-acetyliminoethylene) (pMeOZO) were investigated using transmission electron microscopy and differential scanning calorimetry (DSC) techniques. It was found that a lamellar structure was induced in the block copolymer even at a low content (5%) of poly(N-acetyliminoethylene) as a consequence of the specific, dense, layered texture of the poly(HECA-co-DNBM) blocks, having an electron donor-acceptor complex character. The incorporation of poly(N-acetyliminoethylene) resulted in film quality improvement. The addition of small amounts of the block copolymer to the incompatible mixture of poly(HECA-co-DNBM) and pMeOZO having an appropriate composition leads to homogeneous blends able to form continuous films.     

The steeple spire of the Parma Cathedral: An analysis of the glazed bricks and mortars

In October 2009, a terrible lightning struck the steeple spire of the Parma Cathedral, causing a fire. The fire-fighting operation made possible the discovery of the original spire ceiling made up by dichromatic glazed bricks, white and black, dating from the 14th century. Original materials presented a relevant decay, both for the high temperatures reached during the fire and for lack of maintenance. The research presents the first study of glazed bricks of the 14th century in Po Valley (Italy) with the purpose of collect chemical, mineralogical and petrographic data on the dichromatic glazed bricks. Brick samples with different kind of glazes and mortars exposed at different condition of fire were analyzed. The following techniques were used in the study: X-ray powder diffraction, optical microscopy, scanning electron microscopy analysis, inductively coupled plasma atomic emission spectroscopy and Raman spectroscopy. Glazes, applied on to Ca-rich paste, have a high lead content (41–57 wt%), with an high amount of tin (19–24 wt%) for the white opacified glazes and manganese (about 4.0 wt%) for the black ones. Typological and historical analysis allowed us to define the production technique of bricks and glazes. Mortars are mainly composed of lime binder and carbonate aggregate.     

Addressing the control problem of algae growth in water reservoirs with advanced dynamic optimization approaches

In this work, we develop a lake eutrophication model to determine restoration policies for water quality improvement. This hybrid biogeochemical model has been formulated within a simultaneous dynamic optimization framework as an optimal control problem, whose solution provides limiting nutrient inflow profiles to the lake, as well as in-lake biomanipulation profiles. The water quality model comprises a set of partial differential algebraic equations in time and space, which result from dynamic mass balances on main phytoplankton groups, nutrients, dissolved oxygen and biochemical demand of oxygen. Spatial discretization has been performed in two layers. The simultaneous approach proceeds by discretizing control and state variables by collocation over finite elements and solving the large scale nonlinear program with an interior point method with successive quadratic programming techniques.     

Determination of biogeochemical parameters in eutrophication models with simultaneous dynamic optimization approaches

This work addresses a parameter estimation problem in an ecological water quality model through a simultaneous dynamic optimization approach. The model is based on first principles and has a large number of parameters, which must be estimated based on data collected in the water body under study. Gradients of state variables are considered along the water column, rendering a partial differential equation problem, which is transformed into a differential algebraic (DAE) one by spatial discretization in several water layers. Within a simultaneous approach, the DAE constrained optimization problem is transformed into a large-scale nonlinear programming problem, with a weighted least squares objective function. Main biogeochemical parameters have been obtained, which allow a close representation of the lake dynamics, as it is shown in the numerical results.     

Innovative strategy for designing proton conducting ceramic tapes and multilayers for energy applications

Aim of this work is to present, for the first time, the use of Dynamic Mechanical Analysis as a tool to characterize the thermo-mechanical behavior of green tapes defining the process conditions for the subsequent lamination step. This method was applied on tapes of protonic conductors, key-materials for different applications in the energy sector, from gas separation membranes to solid oxide fuel cells and electrolyzers. The pore former (rice starch) content was found to considerably affect the thermomechanical behavior (elastic and storage moduli, elongation to break, viscosity) of the tape and therefore the lamination process. The temperature required for a proper lamination increases from 50 up to 75 °C passing from the system without rice starch to the one with the highest pore former amount. This work identifies for the first time an optimal lamination viscosity (10¹⁰ Pa s), regardless the tapes formulation, required for a suitable adhesion among the layers.     

CARVE: Context-aware automatic view definition over relational databases

Classical database design strategies, based on the a priori definition of application views to be finally integrated in the design of the global databases, are not appropriate for the design needs of modern, highly dynamic information systems. This paper presents CARVE (Context-Aware Relational View dEfinition), a methodology for context-aware view definition, well-suited for the design of modern, dynamic applications that, in different environments and situations, need to access different portions of data. The methodological approach includes a context-design phase, followed by a phase when each of the possible application contexts is automatically associated with its relevant part of information (context-aware view). Accordingly, CARVE is based on a context model, on guidelines to define partial views related to components of the context, and on a set of operators used to perform partial-view composition to derive the context-aware views. The paper leverages on previously presented preliminary results and introduces and formalizes the overall methodology and its steps, providing a revised and assessed approach. The results of the application of the approach to a set of case studies are reported, together with a careful evaluation.     

Measles encephalitis. Clinical, EEG, and psychometric aspects at follow up (author's transl)

A follow-up of 23 patients with measles encephalitis was carried out six months to ten years after the onset of the disease. Neurological and electroencephalographic features have been examined together with specific psychological tests. Clinical and electsroencephalographic abnormalities, frequently observed during the acute phase of the disease, were rarely detected during the follow-up. However intellectual performances with specific visuo-spatial and attentional involvement are often impaired. Specific psychological tests are required to evaluate visuo-spatial and attention performances, frequently impaired as a consequence of the disease; these are often considered minor psychological disturbances as they are limited to scholastic performances. The Authors conclude that, although measles encephalitis is a fairly serious illness during its acute phase, it tends to improve with time until recovery is complete. The psychological residual deficits, detected during the follow-up, should not be considered as minor disturbances.