Environmental accounting for the lagoon of Venice and the case of fishing

This paper presents the application of the eMergy evaluation, introduced by H.T. Odum as an efficient methodology of environmental accounting. The results of this analysis are a part of a wider sustainability assessment for the Province of Venice realized in 2003. Within a territorial sustainability analysis, it is necessary to implement an environmental accounting method, which is able: to precisely consider the boundaries of the investigated system (spatial scale); to arbitrarily separate the life of the investigated system into periods (temporal scale); to account for both economic and natural support to a given territorial system in order to implement a sustainable management of resources; to assess all the items supporting the system on the basis of a physical unit that is objective (while the traditional economic evaluation method is based on individual preferences, hence it is subjective). The Province of Venice is a very complex system due, on one hand, to the heavy and consolidated presence of industrial activity since the beginning of the 20th century and, on the other hand, to the principal natural ecosystem which characterizes it: the lagoon, the largest wetland in the Mediterranean Sea. The role of the lagoon, as a provider of resources and services is represented by the analysis of two aspects: the lagoon as an ecosystem on the basis of the evaluation of all flows that cyclically support its biotic activity and the lagoon as a productive system on the basis of the contribution of both natural and "economic" inputs that support human activity. In particular, the case of clam fishing will be presented to put on evidence the importance of natural inputs that are systematically neglected by the traditional accounting methodologies.     

The Astrochemical Observatory: Molecules in the Laboratory and in the Cosmos

Astrochemistry is a discipline consolidated recently, although its roots extend back to the dawn of early civilization with the observation and mapping of the sky. The way to the understanding of the common natural laws on earth and in space paved by Galilei's observations by the telescope, has been extended in the last decades, by new technologies such as radioastronomy and space missions. Plenty of new chemistry was surprisingly discovered. Extreme rich information on the chemical “composition” of the universe is being obtained, either from the other planets and satellites in the Solar System, from meteorites and comets, or from the interstellar space. In this article we will present selected topics regarding the chemical structures and reactions being discovered. Particular attention will be devoted to aspects considered as relevant for the prebiotic processes on earth, such as those involving chirality and its role played in the origin and evolution of life.     

Potential energy surfaces for van der waals complexes of rare gases with H2S and H2S2: Extension to xenon interactions and hyperspherical harmonics representation

This article is an account and extension of a series of recent investigations, which using extensive quantum chemical methods provide analytical hyperspherical representations of the potential energy surfaces for the interactions of rare gases with H₂S as a rigid molecule, and H₂S₂, considered as a floppy molecule with respect to torsional mode. For the H₂S‐rare gas systems, the representation is based on a minimal model, here introduced and discussed. For H₂S₂, the study of the interaction with Xe, not considered previously, completes the series. The results are discussed with reference to the properties and trends expected for interactions of van der Waals type. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Rheology of asphalts modified with glycidylmethacrylate functionalized polymers

Asphalt is known to be a colloidal suspension in which asphaltenes are covered by a stabilizing phase of polar resins and form complex micelles that are dispersed in the oily maltenic phase. In order to enhance its mechanical properties (e.g., in road paving), asphalts are often loaded with polymeric materials, thereby obtaining blends that can have different physical or chemical structures, depending on the composition of the added polymer. Asphalts modified by the addition of reactive ethylene terpolymers were prepared and their dielectric and rheological properties were measured both before and after a cure at high temperature. Even if it is not possible to determine the exact nature of the chemical interactions between asphalt and polymer, master curves obtained from dynamic data clearly show that during the cure the material tends to the behavior of a cross-linked network.     

Determination of phenolic compounds and authentication of PDO Lambrusco wines by HPLC-DAD and chemometric techniques

This work proposes a fast and simple method for detection and quantification of phenolic compounds in PDO Lambrusco wines using HPLC-DAD and chemometric techniques. Samples belonging to three different varieties of Lambrusco (Grasparossa, Salamino and Sorbara) were analyzed to provide a methodology appropriate for routine analysis. Given the high complexity of the sample and the coelution among chromatographic peaks, the use of chemometric techniques to extract the information of the individual eluting compounds was needed. Multivariate curve resolution-alternating least squares (MCR-ALS) allowed the resolution of the chromatographic peaks obtained and the use of this information for the quantification of the phenolic analytes in the presence of interferences. Use of multiset analysis and local rank/selectivity information was proven to be crucial for the correct resolution and quantification of compounds. The quantitative data provided by MCR-ALS about the phenolic targets and additional compounds present in the samples analyzed provided wine composition profiles, which were afterwards used to distinguish among wine varieties. Principal component analysis applied to the wine profiles allowed characterizing the wines according to their varieties.     

Rapid Multiphase Flow Dynamics Mapped by Single‐Shot MRI Velocimetry

A new, fast magnetic resonance imaging (MRI) method is described and applied to map flow fields in systems with internal velocities rapidly varying along the streamlines. While conventional MRI techniques encode the velocity information in a preparatory period prior to the imaging acquisition module, our technique repeatedly refreshes the velocity encoding during a single‐shot imaging sequence. In this way, the maximum acceleration responsible for velocity variation of the molecules is increased by up to two orders of magnitude compared to standard procedures. Besides being compatible with high acceleration, this pulse sequence is suited to acquiring in a single scan the multiple velocity images required to construct a full velocity vector map. The power of this new methodology is demonstrated by following the internal dynamics of toluene droplets levitating in a counterflow of water during mass transfer of acetone from the water phase into the drop in the presence of surface‐active impurities. The dramatic reduction in measurement time allows visualization for the first time of the important impact of even small concentrations of acetone on accumulation of surfactants at the drop’s surface.