Assessment of bioenergy potential in Sicily: A GIS-based support methodology

A Geographical Information System (GIS) supported methodology has been developed in order to assess the technical and economic potential of biomass exploitation for energy production in Sicily. The methodology was based on the use of agricultural, economic, climatic, and infrastructural data in a GIS. Data about land use, transportation facilities, urban cartography, regional territorial planning, terrain digital model, lithology, climatic types, and civil and industrial users have been stored in the GIS to define potential areas for gathering the residues coming from the pruning of olive groves, vineyards, and other agricultural crops, and to assess biomass available for energy cultivation. Further, it was possible to assess the potential of biodiesel production, supposing the cultivation of rapeseed in arable crop areas. For the biomass used for direct combustion purposes, the economic availability has been assessed assuming a price of the biomass and comparing it with other fuels. This assessment has shown the strong competitiveness of firewood in comparison with traditional fossil fuels when the collection system is implemented in an efficient way. Moreover, the economic potential of biodiesel was assessed considering the on-going financial regime for fuel. At the same time, the study has shown a significant competitiveness of the finished biomass (pellets), and good potential for a long-term development of this market. An important result was the determination of biofuel production potential in Sicily. An outcome of the study was to show the opportunities stemming from the harmonisation of Energy Policy with the Waste Management System and Rural Development Plan.     

Photocatalytic Inactivation of Legionella Pneumophila and an Aerobic Bacteria Consortium in Water over TiO2/SiO2 Fibres in a Continuous Reactor

A continuous photoreactor, working in a total recycle mode and irradiated by a low-pressure Hg lamp, has been used to study the bactericidal effect of a photocatalyst, formed by TiO₂ embedded in SiO₂ fibres, on Legionella pneumophila and a consortium of common gram-negative aerobic bacteria: (Escherichia coli, Klebsiella sp., Pseudomona sp. and Proteus sp.) in water. The kinetic modeling of the inactivation process, carried out with the measured values of viable bacteria concentration at the outlet of photoreactor, evidenced that for each pass inside the photoreactor the ratio between the outlet and inlet cell concentrations was of order of 0.01 for the inactivation of L. pneumophila. For the other aerobic bacteria, which are usually taken as reference in photocatalytic bacteria inactivation studies, this ratio was of order of 0.3 for the first hour of illumination, while upon prolonged irradiation (up to 9 h) this ratio increased to 0.7. Several factors inducing this latter decrease of efficiency are possible, as e.g. competition for photocatalytic attack between microorganisms and organic compounds released by damaged bacteria or photoinduced alteration of a small fraction of still viable bacteria making them less interactive with the photocatalyst. The inactivation mechanism normally proposed for common bacteria involves an initial attack of the photogenerated radicals to the outer membrane; the consequent membrane dispersion allows the radicals to damage the cytoplasmic membrane. The higher lethality of the photocatalytic method observed towards Legionella: (in comparison to the other aerobic bacteria) is explained considering that the radicals attack the Legionella secretion system, which is adapted for high virulence and would become activated for and through adhesion to the TiO₂ surface. This attack would then be able to inactivate L. pneumophila without dispersing the outer membrane. Apart from this, the water flow through the catalyst fibres can facilitate the bacteria transport towards the anatase surface, and additionally the generated shear stress may help adhesion, at least for some bacteria as E. coli, contributing further to improve the photokilling efficiency; both factors may contribute to the efficiency of this photoreactor configuration.     

Isolation of a hydroxytyrosol-rich extract from olive leaves (<Emphasis Type="Italic">Olea Europaea</Emphasis> L.) and evaluation of its antioxidant properties and bioactivity

In this research, a phenol extract of high hydroxytyrosol (OLPE) content was obtained from olive leaves (Olea europaea L.), and subsequently tested under different contexts. The method used to obtain the OLPE basically involved two steps: the use of strongly-acid aqueous steam, generated from 10% HCl (v/v) at 100°C, to directly hydrolyse the native complex phenols from integral olive leaves, and OLPE recovery by liquid–liquid extraction with ethyl acetate. Hydrolysis time was 1 h. Finally, the dried extract was dissolved in distilled water. The OLPE total phenols were determined by Folin–Ciocalteu’s method and by HPLC analysis. Hydroxytyrosol was about 92% of the total phenols present in OLPE, and the yield was about 0.2% on fresh leaves. OLPE showed antioxidant effects on different food lipids and did not inhibit lactic acid bacteria growth; however, it showed cytotoxicity on NIH/3T3 fibroblasts and human umbilical vein endothelial cells at concentrations higher than 0.32 mM (as hydroxytyrosol).     

Self-piercing riveting for aluminium alloys-composites hybrid joints

In the paper, the growing interest on hybrid joints developed between composite panels and aluminium alloys blanks is focused. The self-piercing riveting operation is considered and its feasibility for the proposed joints verified. The most relevant process parameters were investigated in order to determine a suitable process window and, what is more, the mechanical performances of the developed joints were investigated in order to determine process parameters aimed to maximise them. Finally, the failure mechanics of the obtained joints were considered in order to highlight the mechanisms which occur and determine the lost of the load carrying capability of the joints. The developed experiments demonstrated that self-piercing riveting can be effectively used to join fibreglass composite panels and aluminium blanks.     

The canonical processes of a dramatized approach to information presentation

This paper describes the application “Carletto the spider” in terms of the mapping with the canonical processes of media production. “Carletto the spider” is a character-based guide to a historical site and implements the Dramatour approach for the design of drama-based interactive presentations. Dramatization makes presentations more engaging, thus improving the reception of the content by the user. The major technical issue of the approach is the segmentation of the presentation into audiovisual units that are edited on-the-fly in a way that guarantees dramatic continuity while adapting to the user response. We describe the workflow of the application and its mapping to the canonical processes of media production, envisaging possible standardizations for the application portability.     

Synthesis of Yb nanoparticles by laser ablation of ytterbium target in sodium bis(2-ethylhexyl)sulfosuccinate reverse micellar solution

Surfactant-coated ytterbium nanoparticles were produced by Nd:YAG laser ablation of a Yb bulk target immersed in sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/n-heptane micellar solution. In our experimental conditions, as highlighted by IR spectroscopy, AOT molecules are not decomposed by the intense laser pulses but play a pivotal role in the stabilisation of Yb nanoparticles. The formation of Yb nanoparticles in the liquid phase was monitored by UV-Vis spectroscopy whereas the Yb/AOT composites obtained by evaporation of the organic solvent were characterised by XPS and TEM. Data analysis consistently shows the presence of surfactant-coated, nearly spherical and non-interacting Yb nanoparticles of mean diameter of 3 nm.Moreover, the presence of bigger polycrystalline nanoparticles (about 30%) in coexistence with smaller mono crystalline ones indicates that, after the rapid formation of the pristine Yb nanoparticles from plume condensation, two processes effectively compete for their size distribution: nanoparticle agglomeration and surfactant adsorption.     

Dielectric properties of two phases of crystalline lutetium oxide

High-dielectric constant oxides are the focus of intense current research. As a contribution to the rationalization of the search for candidate materials, we compare the dielectric properties obtained from first-principles linear-response calculations for two phases—the ground state bixbyite and the competing hexagonal structures—of the crystalline oxide Lu₂O₃. The dielectric constants of bixbyite is about 12 and that of hexagonal is about 19 (the electronic constant being about 4.5 in both cases). This difference is due almost exclusively to the vibrational properties, with minor or no influence of charge anomaly differences; as these are related mainly to oxygen vibrations, we argue that the dielectric properties of sesquioxides will be determined mostly by their preferred structure, i.e. they will be poorer for bixbyite (e.g. Y₂O₃) than for hexagonal (e.g. La₂O₃) sesquioxides.     

Indentation Determination of Fatigue Limits in Silicate Glasses

An experimental approach has been used to measure the threshold stress intensity factor ( K _th) for subcritical crack growth in brittle materials using indentation cracks. The data show that K _th values existed in soda-lime-silica and soda-alumina-silica glasses that were tested in a neutral aqueous environment. For the former glass, tests also were performed in acidic and basic solutions. A threshold for subcritical crack growth was observed for acidic conditions but not for alkaline conditions.     

Sandwiched-Beam Procedure for Precracking Brittle Materials

A technique for precracking brittle materials is presented. This procedure, which is called the sandwiched-beam (SB) technique, allows the production of sharp through-thickness cracks with predetermined length in specimens with a rectangular section. A bar, in which an initial notch is produced by using a conventional saw, is inserted between two supporting beams and the sandwich assembly is loaded in three-point bending. Conditions can be defined that allow the stable propagation of a sharp flaw from the notch as the applied load is increased. Then, the cracked bar can be used to determine the fracture toughness. The SB technique is applied to different brittle materials, including soda-lime-silica glass, alumina, Si₃N₄, a SiC _w -Si₃N₄ composite, graphite, a Ti-Al intermetallic, and Carrara marble.     

基于古村落宅间元素模式的村落景观 设计优化策略——以徽州地区为例

新村空间设计语汇模块化是村落景观设计较为普遍的现象,也是地域特征弱化和空间不契合空间行为等问题的主要原因之一。古村落宅间元素是村民日常生活与村落环境在相互影响下长期适应性发展的结果,宅间元素模式研究可促进丰富新村空间设计语汇。以徽州地区古村落为例,从宅间元素的分类、图示、与空间行为的关联3个方面论述了古村落宅间元素模式研究方法论。通过徽州茆田新村景观设计阐述了宅间元素模式的应用,论述了基于古村落宅间元素模式的村落景观设计优化策略,有益于形成并推广地方空间设计语汇,避免过度依赖和使用既有的、来自城市的广场、草坪、树池等元素造成的全国村落的无差别设计。