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Stochastic prediction of wire coupling interference
Full text linkMany EMC analyses of complex systems frequently result in a statement that insufficient knowledge is available to describe accurately the internal relationships of the system's components. This lack of information precludes any rigorous deterministic prediction and, in principle, requires that we express the uncertainties within the model. This paper shows the practical feasibility of stochastic prediction, as an alternative to deterministic simulation, applied to a class of EMC problems intrinsically affected by randomness. The evaluation of the crosstalk in standard cable bundles, in which several wires are tightly and randomly wrapped together, is the concrete problem that we investigate in this context. We developed a technique based on solving the nonuniform multiconductor transmission lines (MTL) for many randomly generated wires' geometries to obtain many crosstalk samples for a single frequency. Finally we validated the method, setting up a case study with published experimental result
Ministero dell’Ambiente e della Tutela del Territorio e del Mare Realizzazione di un sistema di conoscenze a supporto dell’analisi ambientale per la certificazione EMAS dell’AMP di Torre Guaceto (Brindisi).
No full textIl progetto ha lo scopo di realizzare un sistema informativo integrato a supporto delle procedure per il riconoscimento della certificazione EMAS (eco-management and audit scheme) del Sistema di Gestione Ambiente dell'Ente Gestore dell'AMP di Torre Guacet
Mineralizations of the Sila Massif (Calabria, southern Italy): The case study of the Zn-Pb ore deposit of Longobucco
No full textAlthough the mineral deposits of the Longobucco area in the Sila Massif (Calabria, southern Italy) are historically known as metal exploitation sites since ancient times, scientific interest in their study has only recently been renewed (Fregola et al., 2023a). In particular, a detailed mineralogical characterization using modern methodologies and framed in an updated geological context, would help to decipher their genesis. We have collected samples of the mineralized bodies outcropping along a fault zone crosscutting monzodiorites at the “Torrente La Manna” site in the Longobucco area, where Vighi (1953) first observed a sphalerite-galena- pyrite-quartz-calcite mineral association. We have characterized such minerals using optical microscopy, scanning electron microscopy (SEM), electron probe microanalyses (EPMA), and micro-Raman spectroscopy. Sphalerite is the dominant polymetallic mineral, showing color and chemical zoning, and can be used as fingerprint to differentiate the evolution stages of the mineralized deposit; noteworthy its mineralogical characterization is presented in a separate contribution to this congress (Fregola et al., 2023b; session P.40). Our reconstructed paragenetic sequence comprises almost five growth stages. Early minerals include a light- colored Fe-poor sphalerite-I, followed by a darker Fe-richer sphalerite-II formed in association to euhedral quartz-I crystals. The latter show color and chemical zoning of Al, Na, K, Ca. Moreover, we have observed a Mn-rich (1.19±0.03 to 0.49±0.02 wt%) and Mg-poor (up to 0.08±0.01 wt%) calcite, partly hosting REE- fluorcarbonates. The latter minerals are reported here for the first time in the Longobucco area, and consist of synchysite, with 20 to 60 μm grain size, and total REE (Ce, La, Y, Nd, Sm, Pr, Gd, Dy) concentrations ranging between 42.64 and 2.40 wt%. Late stages minerals comprise sphalerite-III, quartz-II, pyrite, and Ag- free galena with low Sb-content (up to 0.09±0.03 wt%).
Fregola, R.A., Ciccolella, A., Festa, V., Ruggieri, G., Schingaro, E., Tursi, F., & Ventruti, G. (2023a) - Review of Polymetallic Mineralization in the Sila and Serre Massifs (Calabria, Southern Italy). Minerals, 13(3), 439. https://doi.org/10.3390/min13030439
Fregola R.A., Ciccolella A., Ruggieri G., Ventruti G., Mesto E. & Schingaro E. (2023b) – Mineralogical characterization of zoned sphalerite from polymetallic mineralization of the Sila Massif (Calabria, Southern Italy): The Longobucco case study. Congresso SGI-SIMP, “The Geoscience paradigm: Resources, Risks and future perspectives”. Potenza, 19-21 sept. 2023, Abstract Book, p. .
Vighi L. (1953) Sulla geologia e sulle mineralizzazioni metallifere della regione di Longobucco in Calabria. Mem. e Note Ist. Geol. Appl. Napoli, 5, 3–61
Mineralogical Characterization of Zoned Sphalerite from the Zn-Pb Ore Deposit of Longobucco (Sila Massif, Calabria, Southern Italy)
No full textPolymetallic ore deposits of the Sila Massif were subjected to raw metals exploitation starting from the Bronze and Iron ages. In spite of this, the scientific literature on their mineralogical characterization is not comprehensive and mostly out-of-date, as recently reported (Fregola et al., 2023). A mineral chemistry study with special focus on some phases could certainly contribute to decipher the origin of these mineral deposits. In this contribution, we present a mineralogical characterization of zoned sphalerite samples collected from the mineralized bodies outcropping along a fault zone cross-cutting monzodiorites at the “Torrente La Manna” site in the Longobucco area (Sila Massif, Calabria). In a separate contribution, we also present results on the whole mineralogical association of this mineralized site, including paragenetic considerations (Ciccolella et al., 2023; Session P.74). Sphalerite from Longobucco has been analysed by optical microscopy, micro-Raman spectroscopy, scanning electron microscopy (SEM), electron probe micro analyses (EPMA), and single crystal X-ray diffraction. Chemical micro-analyses revealed that sphalerite contains minor to trace amounts of Fe (0.803±0.021 to 9.550±0.064 wt%), Cd (up to 0.685±0.020 wt%), Hg (0.176±0.033 to 0.461±0.039 wt%), Cu (up to 0.454±0.011 wt%), and Co (up to 0.023±0.005 wt%). Sphalerite from Longobucco systematically shows colour and chemical zoning, with darker coloured growth bands due to enriched Fe-content. Sector zoning of Cd is also observed. The optical and paragenetic study allowed us to associate the different colour zones to different growth episodes. In particular, sphalerite of the first generation (sphalerite-I) is lighter coloured and Fe-poorer, with respect to the darker and Fe-richer one of the second generation (sphalerite-II). Micro-Raman spectroscopy and single crystal X-ray diffraction were performed on the different colour zones. In particular, Raman spectra show that number, position and relative intensity of the bands in the spectral range 250-400 cm-1 are related to the colour zoning and Fe-content of the sphalerite growth bands. These results are in good agreement with the previous literature (Buzatu et al., 2013). Preliminary single crystal X-ray diffraction data detected a slight difference between the lattice parameters of the lighter sphalerite-I (5.4140 ± 0.0009 Å) and of the darker sphalerite-II (5.4194 ± 0.0007 Å). Based on the relationship between Fe-content and cell parameters found in synthetic FexZn(1-x)S solid solutions (Osadchii & Gorbaty, 2010), our results would correspond to a difference from 0.06 to 0.15 mole fraction of FeS. Zoned sphalerite indicates a variation in the composition of the mineralizing fluid(s) during the geological history of the Longobucco ore deposit.
Buzatu A., Buzgar N., Damian G., Vasilache V. & Apopei A.I. (2013) – The determination of the Fe content in natural sphalerites by means of Raman spectroscopy. Vibrational Spectroscopy 68, 220-224. https://doi.org/10.1016/j.vibspec.2013.08.007
Ciccolella A., Fregola R.A., Ruggieri G., Tursi F., Festa V., Ventruti G. & Schingaro E. (2023) - Polymetallic mineral deposits of the Sila Massif (Calabria, southern Italy): The case study of Longobucco. Congresso SGI-SIMP, “The Geoscience paradigm: Resources, Risks and future perspectives”. Potenza, 19-21 sept. 2023, Abstract Book, p. .
Fregola, R.A., Ciccolella, A., Festa, V., Ruggieri, G., Schingaro, E., Tursi, F., & Ventruti, G. (2023) - Review of Polymetallic Mineralization in the Sila and Serre Massifs (Calabria, Southern Italy). Minerals, 13(3), 439. https://doi.org/10.3390/min13030439
Osadchii E.G. & Gorbaty Y.E. (2010) - Raman spectra and unit cell parameters of sphalerite solid solutions (FexZn1-xS). Geochim. Cosmochim Acta, 74, 568-573. https://doi.org/10.1016/j.gca.2009.10.02
Protection of fish diversity and target species: the case study of the Torre Guaceto marine protected area
No full textAssessing the potential of an artisanal fishing co-management in the Marine Protected Area of Torre Guaceto (southern Adriatic Sea, SE Italy).
No full textI Sistemi di Gestione Ambientale applicati alle Aree Marine Protette: il caso di Torre Guaceto
No full textSphalerite from Longobucco and Fonte Argentila mineralization (Sila Massif, Calabria, southern Italy): crystal chemistry and genetic implications
No full textSphalerite is the main ore-mineral of the vein-type mineralization of Longobucco (LGB) and Fonte Argentila
(FAR), outcropping within granodiorite of the Sila Batholith (Calabria, southern Italy). Such mineralization are
of historical importance, but not deeply investigated yet (Fregola et al., 2023). We have examined the crystal
chemistry of sphalerite through a combination of optical microscopy (OM), scanning electron microscopy
(SEM), electron probe microanalyses (EPMA), μ-Raman spectroscopy (μ-RS), single crystal X-ray diffraction
(SCXRD), and X-ray powder diffraction (XRPD).
Textural and paragenetic observations using optical microscopy allowed us to discriminate three distinct
generations of sphalerite from LGB and FAR, corresponding to different mineralization episodes of the ore
deposit. Sp-1 is light coloured (from light-yellow to brown), Sp-2 is dark coloured (from reddish-brown to
dark brown), whilst Sp-3 is colourless. Colour variation is mainly due to different Fe-content, with the darker
Sp-2 being the Fe-richest one (up to 11.3 wt.%; 0.21 mol% FeS). Sphalerite contains also minor amounts of
Cd (up to 0.7 wt.%).
The phase composition of sphalerite samples has been confirmed by XRPD.
Data from μ-Raman spectroscopy, collected from sphalerite Sp-1, Sp-2 and Sp-3, have been correlated to
the corresponding Fe concentrations. The colourless Fe-poorest Sp-3 shows the typical spectrum of almost
pure ZnS sphalerite, with the main band at about 350 cm-1 (h3, A3; Raman band due to Zn-S bond vibrations).
Raman spectra of Sp-1 and Sp-2 show a further band at about 300 cm-1 (h1, A1; Raman band due to Fe-S
bond vibrations) becoming gradually dominant with increasing Fe-content, with respect to the Zn-S band. By
plotting the obtained ratios of band intensities (h1/h3) and areas (A1/A3) against the corresponding FeS mole
fractions, our results are in good agreement with the calibrated curves reported by the literature (e.g., Osadchii
& Gorbaty, 2010).
The refined unit cell parameters, measured by SCXRD on Sp-1 and Sp-2 sphalerite of different colours
(from pale yellow to reddish-brown), range between 5.4158 Å and 5.4230 Å. Using these cell parameters and
the corresponding mol% FeS values in the equation by Chareev et al. (2017), we have estimated sphalerite
formation temperatures in the range 117-141°C for the light Sp-1, and up to 192°C for the dark Sp-2. Such
values are in good agreement with those obtained from our preliminary fluid inclusion analyses performed on
quartz, as well as from our geochemical analyses of sphalerite trace element composition (Ciccolella et al.,
2024).
Chareev D.A. et al. (2017) - Single-crystal Fe-bearing sphalerite: synthesis, lattice parameter, thermal expansion coefficient
and microhardness. Phys. Chem. Minerals, 44, 287-296, https://doi.org/10.1007/s00269-016-0856-z.
Ciccolella A. et al. (2024) - The Zn-Pb(-Cu-Fe) mineralization in the northern Sila Massif (Calabria, southern Italy):
Genetic constrains from trace element concentrations in sphalerite. EGU General Assembly 2024, Vienna, Austria,
14-19 Apr 2024, EGU24-3657, https://doi.org/10.5194/egusphere-egu24-3657.
Fregola R.A. et al. (2023) - Review of polymetallic mineralization in the Sila and Serre Massifs (Calabria, southern Italy).
Minerals, 13, 439, https://doi.org/10.3390/min13030439.
Osadchii E.G. & Gorbaty Y.E. (2010) - Raman spectra and unit cell parameters of sphalerite solid solutions (FexZn1-xS).
Geochim. Cosmochim. Ac., 74, 568-573, https://doi.org/10.1016/j.gca.2009.10.022
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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