Search results for " Flux"
showing 10 items of 583 documents
An Investigation of the Thermal Effects in Orthogonal Cutting Associated with Multilayer Coatings
2001
Abstract This paper deals with an experimental and analytical investigation into the tool-chip interface behaviour, influencing the temperature and heat transfer at the multilayered coated-tool rake face during orthogonal cutting of carbon and stainless steels. New methodology for assessing the amount of thermal energy generated when machining with a coated tool insert with natural and restricted contact coupled with a metallic chip, using thermophysical properties of the sliding materials is developed in this study. It was proven, based on the heat flux analysis, that the use of advanced coatings with an intermediate Al 2 O 3 layer can substantially improve the heat flow into the chip at d…
Energy of dendritic avalanches in thin-film superconductors
2018
A method for calculating stored magnetic energy in a thin superconducting film based on quantitative magneto-optical imaging is developed. Energy and magnetic moment are determined with these calculations for full hysteresis loops in a thin film of the superconductor NbN. Huge losses in energy are observed when dendritic avalanches occur. Magnetic energy, magnetic moment, sheet current and magnetic flux distributions, all extracted from the same calibrated magneto-optical images, are analyzed and discussed. Dissipated energy and the loss in moment when dendritic avalanches occur are related to each other. Calculating these losses for specific spatially-resolved flux avalanches is a great ad…
A non-local model of fractional heat conduction in rigid bodies
2011
In recent years several applications of fractional differential calculus have been proposed in physics, chemistry as well as in engineering fields. Fractional order integrals and derivatives extend the well-known definitions of integer-order primitives and derivatives of the ordinary differential calculus to real-order operators. Engineering applications of fractional operators spread from viscoelastic models, stochastic dynamics as well as with thermoelasticity. In this latter field one of the main actractives of fractional operators is their capability to interpolate between the heat flux and its time-rate of change, that is related to the well-known second sound effect. In other recent s…
Representation of capacity drop at a road merge via point constraints in a first order traffic model
2018
We reproduce the capacity drop phenomenon at a road merge by implementing a non-local point constraint at the junction in a first order traffic model. We call capacity drop the situation in which the outflow through the junction is lower than the receiving capacity of the outgoing road, as too many vehicles trying to access the junction from the incoming roads hinder each other. In this paper, we first construct an enhanced version of the locally constrained model introduced by Haut et al. (Proceedings 16th IFAC World Congress. Prague, Czech Republic 229 (2005) TuM01TP/3), then we propose its counterpart featuring a non-local constraint and finally we compare numerically the two models by c…
The European contribution to the development and validation activities for the design of IFMIF lithium facility
2013
The International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-driven intense neutron source where candidate materials for fusion reactors will be tested and validated. The high energy neutron flux is produced by means of two deuteron beams (total current of 250 mA, energy of 40 MeV) that strikes a liquid lithium target circulating in a lithium loop of IFMIF plant. The European (EU) contribution to the development of the lithium facility comprises five procurement packages, as follow: (1) participation to the experimental activities of the EVEDA lithium test loop in Oarai (Japan); (2) study aimed at evaluating the corrosion and erosion phenomena, promoted by lithium, for …
Soil carbon dynamics as affected by long-term contrasting cropping systems and tillages under semiarid Mediterranean climate
2014
Abstract In a dryland Mediterranean agrosystem (Sicily, Italy) a comparative study was carried out among two crop systems (wheat/wheat and wheat/bean) after 19 years under three most used tillage managements (conventional, dual layer and no-tillage), in order to ascertain the effects of those experimental factors, single and combined, on various soil organic C pools (total and extractable organic C, microbial biomass C, basal respiration). Field CO 2 fluxes from soil, throughout a year, were also determined. Moreover, C input and output were assessed, as well as microbial and metabolic quotients. Tillage management more than cropping system affected the soil organic C stored in the first 15…
A critical analysis of three remote sensing-based actual evapotranspiration assessment methods over sparse crops agricultural areas
2010
During last two decades the increasing availability of remotely sensed acquisitions in the thermal infrared part of the spectrum has encouraged hydrologist community to develop models and methodologies based on these kind of data. The aim of this paper is to compare three methods developed to assess the actual evapotranspiration spatial distribution by means of remote sensing data. The comparison was focused on the differences between the "single" (SEBAL) and "two" source (TSEB) surface energy balance approaches and the S-SEBI semi-empirical method. The first assumes a semiempirical internal calibration for the sensible heat flux assessment; the second uses a physically based approach in or…
The sea–air exchange of mercury (Hg) in the marine boundary layer of the Augusta basin (southern Italy): Concentrations and evasion flux
2013
Abstract The first attempt to systematically investigate the atmospheric mercury (Hg) in the MBL of the Augusta basin (SE Sicily, Italy) has been undertaken. In the past the basin was the receptor for Hg from an intense industrial activity which contaminated the bottom sediments of the Bay, making this area a potential source of pollution for the surrounding Mediterranean. Three oceanographic cruises have been thus performed in the basin during the winter and summer 2011/2012, where we estimated averaged Hg atm concentrations of about 1.5 ± 0.4 (range 0.9–3.1) and 2.1 ± 0.98 (range 1.1–3.1) ng m −3 for the two seasons, respectively. These data are somewhat higher than the background Hg atm …
Storm Energy Flux Characterization along the Mediterranean Coast of Andalusia (Spain)
2019
This paper investigates wave climate and storm characteristics along the Mediterranean coast of Andalusia, for the period 1979&ndash
Mercury fluxes from volcanic and geothermal sources: an update
2014
We review the state of knowledge on global volcanogenic Hg emissions to the atmosphere and present new data from seven active volcanoes (Poás, Rincón de la Vieja, Turrialba, Aso, Mutnovsky, Gorely and Etna) and two geothermal fields (Las Pailas and Las Hornillas). The variability of Hg contents (c. 4–125 ng m−3) measured in gaseous emissions reflects the dynamic nature of volcanic plumes, where the abundances of volatiles are determined by the physical nature of degassing and variable air dilution. Based on our dataset and previous work, we propose that an average Hg/SO2 plume mass ratio of c. 7.8×10−6 (±1.5×10−6; 1 SE, n=13) is best representative of open-conduit quiescent degassing. Takin…