High temperature melt viscosity and fragile to strong transition in Zr–Cu–Ni–Al–Nb(Ti) and Cu47Ti34Zr11Ni8 bulk metallic glasses

The molten viscous behavior of Vitreloy 106, 106a, 105 and 101 bulk metallic glass-forming alloys was investigated at temperatures above T_liq. Couette concentric cylinder viscometry was used to determine the isothermal and continuous cooling melt viscosities. Isothermal three point beam bending measurements of the viscosity in the vicinity of T_g revealed a kinetically stronger liquid at low temperatures than at high temperatures, near T_liq. This behavior is revealed to be the result of a fragile to strong transition in the undercooled liquid, possibly due to polyamorphism.     

Recycling of Screen Glass Into New Traditional Ceramic Materials

The cleaned cathode ray tube (CRT) glass comes from the dismantling plant of TV and PC color kinescopes and has been used to completely replace both feldspathic and inert components of a traditional ceramic body. Panel glass has been added (up to 20 wt%) to a mixture of two commercial ball clays in order to obtain laboratory tiles sintered at 1210°C. Densification has been studied according to ISO rules, while sinterability has been estimated by optical dilatometry. The samples obtained showed main properties similar to commercial ceramic floor and/or wall tiles.     

Graphene sublattice symmetry and isospin determined by circular dichroism in angle-resolved photoemission spectroscopy

The Dirac-like electronic structure of graphene originates from the equivalence of the two basis atoms in the honeycomb lattice. We show that the characteristic parameters of the initial state wave function (sublattice symmetry and isospin) can be determined using angle-resolved photoemission spectroscopy (ARPES) with circularly polarized synchrotron radiation. At a photon energy of hν = 52 eV, transition matrix element effects can be neglected allowing us to determine sublattice symmetry and isospin with high accuracy using a simple theoretical model.     

Reaction Pathways in the Reduction of NO x Species by CO over Pt–Ba/Al2O3: Lean NO x Trap Catalytic Systems

The reduction by CO of NO _x species stored over Pt–Ba/Al₂O₃ Lean NO _x Trap systems is analysed in this work. The reaction mechanisms and pathways leading to N₂ formation both under dry and wet conditions are investigated by complementary transient dynamic experiments and FTIR analyses.     

NH3–NO/NO2 SCR for Diesel Exhausts Aftertreatment: Reactivity, Mechanism and Kinetic Modelling of Commercial Fe- and Cu-Promoted Zeolite Catalysts

The activity and the mechanism of the main reactions in the NO/NO₂–NH₃ SCR reacting system were comparatively investigated over a Fe- and a Cu-promoted commercial zeolite catalyst for the aftertreatment of Diesel exhausts. A dynamic micro-kinetic model in close agreement with all the details of the SCR catalytic chemistry was also developed.     

Effects of orlistat therapy on plasma concentrations of oxygenated and hydrocarbon carotenoids

Orlistat is a lipase inhibitor that is applied for treating obesity. Lipases are required for digestion and absorption of dietary lipids and fat-soluble vitamins and carotenoids. The aim of this study was to compare the effects of orlistat therapy on plasma concentrations of oxygenated (β-cryptoxanthin, lutein/zeaxanthin) and hydrocarbon (α-, β-carotene, lycopene) carotenoids. Six patients with a body mass index (BMI)≥30 kg/m² received 360 mg/d orlistat over 4.5 mon. Plasma carotenoid concentrations were determined at baseline (T ₀) and after 3 (T ₃) and 4.5 mon (T _4.5) along with anthropometric, dietary, and biochemical indices, including plasma lipids, retinol, α- and γ-tocopherols, and FA. Baseline BMI was 32.7±1.97 kg/m². Five of six patients lost weight; the average weight loss was 3.6±2.4% (P=0.47). There were no significant changes in dietary carotenoid intakes. In contrast, plasma α-and β-carotene concentrations decreased significantly from T ₀ to T _4.5 by 45% (P=0.006) and 32% (P=0.013), respectively. Plasma lycopene decreased from T ₀ to T ₃ but increased again from T ₃ to T _4.5, while β-cryptoxanthin and lutein/zeaxanthin concentrations did not change. There were no significant alterations in tocopherol, retinol, and FA concentrations. In conclusion, even though weight loss was not significant, orlistat therapy was associated with significant decreases in plasma concentrations of the highly lipophilic hydrocarbon carotenoids, α- and β-carotene.     

Inventory and life cycle assessment of an Italian automotive painting process

Clean Technologies and Environmental Policy - In the current context of the European Environmental legislation and standards, the automotive sector is expected to continuously improve the vehicles...     

A distributed framework for multi-risk assessment of natural hazards used to model the effects of forest fire on hydrology and sediment yield

Within the European Commission-funded MEDIGRID project, Grid computing technology is used to integrate various natural hazard models and data sets, maintained independently at different centres in Europe, into a single system, accessible to users over the internet. Each centre forms a process (application) or data storage node and has been fitted with the Globus toolkit, which provides the distributed computing environment functionality that is required for the system set up. In addition, several Grid data management components were developed to allow the system to operate on different computing platforms. Access to the data and application management services is enabled through a Grid Portal. A series of portlets enable users to access the system, providing a personalised interface to the Grid. Integration of the individual models required them to be modified as web services, so as to be run remotely over the internet. As the models have different data characteristics, a common data format was adopted for creating harmonised data sets and allowing the exchange of data between the models. As an example, the Fire Spread Engine model is used to derive a map of areas that have been burnt by fire. This forms an input to the SHETRAN hydrology, soil erosion and landslide model, which in turn could provide data for other models such as vegetation regeneration. The use of the system is demonstrated for a site in south-west Spain where a large forest fire occurred on 2 August 2003. The MEDIGRID system marks an advance in the integration of independently constructed models to provide improved hazard assessment technology.