Search results for "Electrical Resistivity"

Hydrogeological and geotechnical modeling of the foundation soils of Maredolce Lake in Palermo, aided by geophysical surveys

2019

The cultural heritage of Maredolce (Palermo) includes an Arab-Norman castle that originally stood on the shores of an artificial lake carved out of a basin dug out of the calcarenite and filled with water thanks to the channeling of the springs of San Ciro upstream. Subsequently, the lowering of the water table and the high hydraulic permeability of the outcropping rocks caused the lake to dry up. Recently, a project of enhancement of the cultural heritage required the restoration of the lake. The geophysical study presented here, including the integrated use of different techniques such as electrical and seismic tomography, Multichannel Analysis of the Surface Waves and ambient vibration r…

Multivariate modelling of geophysical tomography data to identify a tectonized area

2018

An integrated analysis approach, based on geological investigations and 2D high-resolution shallow geophysical data, was proposed along a slope in the Bellolampo landfill area (Palermo, Italy) where the presence of a fault zone was hypothesized. Geophysical surveys included electrical resistivity tomography (ERT), induced polarization tomography (IPT) and seismic refraction tomography (SRT) techniques. The inversion of single geophysical parameter often does not allow to justify the complexity of the subsoil structures. The most appropriate solution should be to add additional physical or geological information so to get a constrained geological model. However, it is not at all easy to work…

Integrated archaeological and geophysical survey for searching the roman temple of Augustus in Terragona, Spain

2009

The summit part of Mount Etna revealed by High Resolution DC Electrical Resistivity Tomography coupled with complementary geophysical and soil gas te…

2016

Between 25 June and 13 July 2015 a very deep ERT profile (Pole-Dipole configuration, 40m spacingbetween electrodes and a remote electrode located at ~10km from the acquisition points) has been performedin the framework of the “MED-SUV” Project. Self-potential, soil gas concentrations (CO2, 222Rn, 220Rn, He,H2 and CH4) and soil temperature measurements were coupled to the ERT profile with a spacing of 20m(except for Rn: 40m). The NE-SW profile crossed Etnas summit craters in the middle of the 5720m ERTtotal length. Six roll along protocols of . of the dispositive (600m out of 2520m tot) have been carried outand, for the first time, a high resolution DC ERT profile reached the noticeable inve…

A constrained geophysical model of the landslide that affects the Agrigento Cathedral

2012

Numerical investigation of the influence of EM-fields on fluid motion and resistivity distribution during floating-zone growth of large silicon singl…

2001

The floating-zone-process with needle-eye inductor is a complex process with many coupled parameters that have nonlinear influence on the process stability and resistivity distribution in the silicon single crystal. To fulfill the requirements of semiconductor industry for tighter specification of resistivity distribution, additional means like magnetic fields can be used to reach a more homogeneous resistivity distribution without disturbing process stability. The current paper analyses the influence of static and alternating fields on the fluid motion and macroscopic and microscopic resistivity profile by means of numerical calculations. It is found that with a lower frequency of the HF-i…

Electrical Resistivity Anisotropy of Silicon-Doped n-Indium Selenide

1993

TCO/Ag/TCO transparent electrodes for solar cells application

2014

Among transparent electrodes, transparent conductive oxides (TCO)/metal/TCO structures can achieve optical and electrical performances comparable to, or better than, single TCO layers and very thin metallic films. In this work, we report on thin multilayers based on aluminum zinc oxide (AZO), indium tin oxide (ITO) and Ag deposited by RF magnetron sputtering on soda lime glass at room temperature. The TCO/Ag/TCO structures with thicknesses of about 50/10/50 nm were deposited with all combinations of AZO and ITO as top and bottom layers. While the electrical conductivity is dominated by the Ag intralayer irrespective of the TCO nature, the optical transmissions show a dependence on the natur…

Molecular materials with conducting and magnetic properties based on ET and [ M(tdas)2]x-dithiolenes

2004

Two hybrid molecular materials showing a combination of magnetic and conducting properties, the charge-transfer (ET) 2 [Fe(tdas) 2 ] (1) and (ET)Ni(tdas) 2 (2), (ET=bis(ethylenedithio) tetrathiafulvalene; M=Fe, Ni; tdas=l,2,5-thiadiazole-3,4-dithiolate) salts, are characterized by vibrational (IR and Raman) and UV-VIS-NIR spectroscopies. These studies have proved to be effective and diagnostic tools in identifying the oxidation state (partial or integer) and the packing pattern (dimers or segregated stacks) of the ET donor only, since no v(C=C) group vibration sensitive to the charge of M(tdas) 2 complexes has been observed. This is ascribed to the extensive electron-delocalization inside t…

Scanning tunnelling spectroscopy study of paramagnetic superconducting β''-ET(4)[(H(3)O)Fe(C(2)O(4))(3)]·C(6)H(5)Br crystals.

2010

Scanning tunnelling spectroscopy (STS) and microscopy (STM) were performed on the paramagnetic molecular superconductor β''-ET(4)[(H(3)O)Fe(C(2)O(4))(3)]·C(6)H(5)Br. Under ambient pressure, this compound is located near the boundary separating superconducting and insulating phases of the phase diagram. In spite of a strongly reduced critical temperature T(c) (T(c) = 4.0 K at the onset, zero resistance at T(c) = 0.5 K), the low temperature STS spectra taken in the superconducting regions show strong similarities with the higher T(c) ET κ-derivatives series. We exploited different models for the density of states (DOS), with conventional and unconventional order parameters to take into accoun…