937 research outputs found
Spontaneous polarisation of the neutral interface for valence asymmetric coulombic systems
In this paper, we discuss the phenomenon of a spontaneous polarisation of a
neutral hard planar interface for valence asymmetric coulombic systems. Within
a field theoretical description, we account for the existence of non trivial
charge density and electric potential profiles. The analysis of the phenomenon
shows that the effect is related to combinatorics in relation with the
existence of the two independent species cations and anions. This simple and
basic feature is related to the quantum mechanical properties of the system.
The theoretical results are compared with numerical simulations data and are
shown to be in very good agreement, which a fortiori justifies our physical
interpretation.Comment: 12 pages, 11 figure
From <i>extractive</i> to <i>transformative</i> industries:paths for linkages and diversification for resource-driven development
While conventional wisdom has placed the focus of the mining and oil and gas sectors on the fact of extraction, a prolific line of the debate on these industries is shifting towards the extent to which resources, as initial assets, can be transformed into broader-based development by promoting cross-sectoral linkages and diversification. This paper provides an overview of the Special Issue of Mineral Economics “Can Mining be a Catalyst for Diversifying Economies”, exploring trends and suggesting challenges for concepts and practice in these industries. It points to the Post-2015 Development Agenda as an opportunity of a transformational role for the mining industry
Shedding Light on Diatom Photonics by means of Digital Holography
Diatoms are among the dominant phytoplankters in the worl's ocean, and their
external silica investments, resembling artificial photonics crystal, are
expected to play an active role in light manipulation. Digital holography
allowed studying the interaction with light of Coscinodiscus wailesii cell wall
reconstructing the light confinement inside the cell cytoplasm, condition that
is hardly accessible via standard microscopy. The full characterization of the
propagated beam, in terms of quantitative phase and intensity, removed a
long-standing ambiguity about the origin of the light. The data were discussed
in the light of living cell behavior in response to their environment
Effects of two plant oil-based products on the mortality of red palm weevil and morpho-physiological characteristics of palm
The red palm weevil (RPW), Rhynchophorous ferrugineus Oliver (Coleoptera: Curculionidae), is an economically important, tissue-boring pest of date palm in many parts of the world. The aim of the work was to investigate the effects of two plant oil-based products (BRK6 and BRK9) on the mortality of RPW (Exp. 1) and morpho-physiological characteristics of palm (Exp. 2). Laboratory experiments showed that the two mixture of oils BRK6 and BRK9 showed larvicide and adulticide properties. These properties were more pronounced on BRK9 than BRK6. The lethal concentration for 50% of individuals (LC50) calculated by probit, of BRK6 was 0.22% (for the 90% of individuals LC90 = 0.34) while for BRK9 the calculated LC50 was 0.10% (LC90 = 0.66). These data show that a smaller amount of BRK9 oil was required to induce the 50% of mortality of RPW larvae. As regards to the adults, BRK9 and BRK6 were effective only at the highest concentration (2 and 5%, respectively). Finally, injection of BRK9 into the palm trunk showed to promote chlorophyll content and photosynthesis of leaves thanks to a good translocation of zinc
Ageing test of the ATLAS RPCs at X5-GIF
An ageing test of three ATLAS production RPC stations is in course at X5-GIF,
the CERN irradiation facility. The chamber efficiencies are monitored using
cosmic rays triggered by a scintillator hodoscope. Higher statistics
measurements are made when the X5 muon beam is available. We report here the
measurements of the efficiency versus operating voltage at different source
intensities, up to a maximum counting rate of about 700Hz/cm^2. We describe the
performance of the chambers during the test up to an overall ageing of 4 ATLAS
equivalent years corresponding to an integrated charge of 0.12C/cm^2, including
a safety factor of 5.Comment: 4 pages. Presented at the VII Workshop on Resistive Plate Chambers
and Related Detectors; Clermont-Ferrand October 20th-22nd, 200
Field theoretical representation of the Hohenberg-Kohn free energy for fluids
To go beyond Gaussian approximation to the Hohenberg-Kohn free energy playing
the key role in the density functional theory (DFT), the density functional
\textit{integral} representation would be relevant, because field theoretical
approach to perturbative calculations becomes available. Then the present
letter first derives the associated Hamiltonian of density functional,
explicitly including logarithmic entropy term, from the grand partition
function expressed by configurational integrals. Moreover, two things are done
so that the efficiency of the obtained form may be revealed: to demonstrate
that this representation facilitates the field theoretical treatment of the
perturbative calculation, and further to compare our perturbative formulation
with that of the DFT.Comment: 5 pages, revtex, modified on 13 April 2000 [see eqs. (3), (6), and
(13)
Usefulness of point shear wave elastography to assess the effects of extracorporeal shockwaves on spastic muscles in children with cerebral palsy: an uncontrolled experimental study
Damage evolution in fuselage stiffened composite panels under asymmetrical bending loading conditions
In this paper, the damage mechanisms of reinforced composite panels subjected to symmetrical and asymmetrical flexural loading conditions have been investigated. The composite components are representative of a regional aircraft fuselage. Three-point bending tests numerical simulations have been used to assess the influence of the different test parameters on the damage behavior of the investigated component. Then, the most representative configuration has been selected for the experimental bending test. the outputs from the numerical simulations, in terms of stiffness and damage onset and propagation, has been employed, in combination with the experimental data, to accurately describe the damage mechanisms associated to the asymmetric application of the load
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