Textured Tl(1223)/Ag Tapes Prepared by Electrophoretic Deposition

The conventional powder-in-tube technique does not allow to produce textured Tl(1223) tapes. An electrophoretic deposition technique was used to produce uniform layers of controlled thickness on Ag substrates by a simple and reproducible procedure. A high degree of texture, comparable with the one generally observed for Bi-based tapes was obtained thanks to the appropriate grain morphology, by simply alternating deposition and uniaxial pressing. After annealing, critical current densities of 11'000 A/cm² were reached.     

Smoke suppression by ammonium polyphosphate in poly(acrylonitrile) combustion

The influence of ammonium polyphosphate (APP) on the smoke emission of poly(acrylonitrile) (PAN) has been examined, and its mechanism of action as a smoke suppressant agent has been investigated. Smoke density and corresponding residual char data, as a function of temperature, were obtained in order to characterize the smoke propensity of PAN. The amount of generated smoke, both in smoldering and flaming conditions, was considerably lowered by the presence of APP, and higher char yields were obtained. Beside the smoke suppression, flame inhibition effect of APP on PAN was evidenced. Thermogravimetry (TG), oxygen index (OI), and nitrous oxide index (NOI) experiments were also performed. On the basis of our data, APP appears to act as a char-forming agent in PAN combustion. Both smoke suppression and flame inhibition effects can be considered a consequence of this action.     

Smoke dilution methods for the evaluation of the smoke emission from burning polymers: A comparative approach

A comparative approach to the determination of smoke emission from burning polymers has been attempted, and a number of combustion conditions and detection devices have been tried to choose a test method for measuring the smoke proiduction of materials. The combustion apparatus adopted is a hot-air quartz furnace that permits the measured by dynamic method from combustion of PAN, PVC and PVC mixed with some metal oxiders, have been compared with those obtained by an accumulation mode. For PVC the intensity of the light scattered from the evolving smoke has been measured as an alternative to smoke density.     

Macroscopic transport by synthetic molecular machines

Nature uses molecular motors and machines in virtually every significant biological process, but demonstrating that simpler artificial structures operating through the same gross mechanisms can be interfaced with-and perform physical tasks in-the macroscopic world represents a significant hurdle for molecular nanotechnology. Here we describe a wholly synthetic molecular system that converts an external energy source (light) into biased brownian motion to transport a macroscopic cargo and do measurable work. The millimetre-scale directional transport of a liquid on a surface is achieved by using the biased brownian motion of stimuli-responsive rotaxanes ('molecular shuttles') to expose or conceal fluoroalkane residues and thereby modify surface tension. The collective operation of a monolayer of the molecular shuttles is sufficient to power the movement of a microlitre droplet of diiodomethane up a twelve-degree incline.     

Development of the design of car bodywork from first concept to prototype

This paper deals with the design of car bodies from the first sketches to the master model, ie to the last stage before mass manufacture. Close scrutiny of the various steps needed in drawing, control and construction make it possible to determine which of them can be replaced by modern automatic procedures.     

Phase-Sensitive Reflective Imaging Device in the mm-wave and Terahertz Regions

Two Free Electron Laser sources have been developed at ENEA-Frascati for a variety of applications: A Compact Free Electron Laser (C-FEL) that provides coherent radiation in the frequency range between 90 and 150 GHz Gallerano et al. (Infrared Phys. and Techn. 40:161, 1999), and a second source, FEL-CATS, which utilizes a peculiar radio-frequency structure to generate coherent emission in the range 0.4 to 0.7 THz Doria et al. (Phys. Rev. Lett 93:264801, 2004). The high peak power of several kW in 15 to 50 ps pulses, makes these sources particularly suitable for the assessment of exposure limits in biological systems and for long range detection. In this paper we present a phase-sensitive reflective imaging device in the mm-wave and THz regions, which has proven to be a valuable tool in the biological Ramundo-Orlando et al. (Bioelectromagnetics 28:587–598, 2007), environmental Doria et al. (2005) and art conservation fields Gallerano et al. (2008). Different setups have been tested at different levels of spatial resolution to image objects from a few centimeter square to larger sizes. Images have been compared to identify and characterize the contrast mechanism.     

Evolution of aroma compounds of murtilla fruits (Ugni molinae Turcz) during storage

BACKGROUND: ‘Murtilla’, ‘mutilla’ or ‘murta’ (Ugni molinae Turcz) is a native Chilean species that produces a small berry fruit with a special aroma, whose volatile compounds have not yet been identified. The fruit may be consumed raw and also as jams, juice, canned products, confections and liquor. RESULTS: At the beginning and end of the storage, 24 volatile compounds were identified in murtilla fruit aroma and the concentration of these compounds in murtilla fruit ranged from 1.2 to 250.5 µg kg^?1 fresh weight. Methyl 2‐methyl butanoate, ethyl butanoate, ethyl 2‐methyl butanoate, methyl hexanoate, ethyl hexanoate, methyl benzoate and ethyl benzoate were the major components, all of which have been reported as potent odors in other aromatic fruits. Based on estimated odor activity value, the most potent compound in the murtilla fruit aroma were ethyl hexanoate and 4‐methoxy‐2,5‐dimethyl‐furan‐3‐one. The statistical analysis showed that the storage produced a distinct effect on the same volatile compounds released from the murtilla ecotypes. CONCLUSION: The volatile compounds identified in murtilla fruit aroma, which may be described as fruity, sweet and floral, have been found in other aromatic fruits. Concerning the aroma, the murtilla fruit from ecotype 19‐1 was shown to be the best in cooled storage. Copyright © 2007 Society of Chemical Industry     

Determination of killer activity in yeasts isolated from the elaboration of seasoned green table olives

In this work 51 yeasts strains isolated from seasoned green table olives and belonging to the Candida, Debaryomyces, Kluyveromyces, Pichia, and Saccharomyces genera were characterized by their killer activity in different conditions. Killer activity of isolates was analyzed in a medium with different pH's (3.5 to 8.5) and NaCl concentrations (5, 8, and 10%). At every pH tested, all the genera studied had killer strains, although the smallest percentages of killer yeasts were found at the highest pH (8.5). The presence of 5 and 8% NaCl increased the detected killer percentage, but the highest salt concentration (10%) decreased it. The interaction between the reference killer yeasts and yeasts isolated from olives was analyzed. Most isolates were killer-sensitive to one or more killer reference strains. Only 2 of the 51 strains tested were considered killer-neutral. Cross-reaction trials between isolates and spoilage yeasts showed that, of the isolates, nine killer strains, belonging to Debaryomyces hansenii, Kluyveromyces marxianus, Pichia anomala, Pichia guilliermondii, and Saccharomyces cerevisiae, had the broadest spectra of action against yeasts that cause spoilage. These killer yeasts and the toxins that they produce are candidates for further investigation as suppressors of indigenous olive table yeast growth. The results confirmed the highly polymorphic expression of the killing activity, with each strain showing different killer activities. This method may thus be very useful for simple and rapid characterization of yeast strains of industrial interest.