Multi-length TDR probes: future perspectives

In this contribution we will propose the use of multi-length TDR probes for measurements of the dielectric and possibly magnetic characteristics of a material under test (MUT) as a function of frequency. The multi-length strategy, consisting in making use of a TDR probe with adjustable length of the conductors, can allow the meaningful increase of information achievable about the MUT at each test frequency. We are still at an early stage about these possibilities, and many questions are still open at this time. However, some of our previous studies [1-3] show that the method is promising and can permit the acquisition of some information not intrinsically available from a traditional TDR probe, especially if the MUT shows a dispersive behaviour and possibly magnetic properties. In this contribution, we will discuss the recent work related in particular to geophysical applications.AcknowledgementsThis work in progress is being carried out within the European Cost Action CA17115 Mywave.References[1] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, vol. 16, n.2, pp.1-9, DOI:10.3997/1873-0604.2017046, 2018.[2] R. Persico, I. Farhat, L. Farrugia, S. d&#8217;Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, doi.org/10.2113/JEEG23.4.437, 23 (4): 437-442, 2018.[3] I. Farhat, L. Farrugia, R. Persico, S. D&#8217;Amico, and C. Sammut, Preliminary Experimental Measurements of the Dielectric and Magnetic Properties of a Material with a Coaxial TDR Probe in Re&#64258;ection Mode, Progress In Electromagnetics Research M, Vol. 91, 111&#8211;121, 2020.

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Use of multi-length TDR data aimed to infer the dispersion law of nonmagnetic materials

10.5194/egusphere-egu2020-1664 ◽

2020 ◽

Author(s):

Iman Farhat ◽

Raffaele Persico ◽

Lourdes Farrugia ◽

Charles Sammut

Keyword(s):

Magnetic Properties ◽

Dielectric Properties ◽

Transmission Lines ◽

Measurement Data ◽

Biological Tissues ◽

Time Domain Reflectometry ◽

Coaxial Cable ◽

Near Surface ◽

Dispersion Law ◽

Near Surface Geophysics

This contribution presents a method of multi-length transmission lines, filled with or embedded in the material under test (MUT), based on time domain reflectometry (TDR), to measure the dispersion law of a nonmagnetic material. This approach is essential and can be exploited in both radiofrequency and microwave applications. The proposed technique expands on studies presented in [1-2], where dielectric, magnetic and conductive losses are accounted for by the complex relative permittivity and permeability of the MUT.Many materials of interest in geophysical [3-4] and biomedical [5-6] applications are non-magnetic but preliminary measurements with the proposed technique can help to determine if the MUT indeed has magnetic properties. Moreover, it is shown that establishing the non-magnetic nature of the MUT constitutes meaningful a-priori information that allows disambiguating experimental results, even with limited data in the frequency range of interest.Results relative to two different types of multi-length measurement data, namely data acquired by considering different lengths of a TDR probe entirely embedded in (or embedding) the MUT and data achieved from a sequential progressive embedding of the probe in the MUT (or, vice-versa, of the MUT in the probe) are presented to illustrate the method. The pros and cons of presented cases are also discussed. &#160;AcknowledgementsThis work is supported by the European Cost Action &#8220;Mywave&#8221; CA17115.References[1] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, vol. 16, n.2, pp.1-9, DOI:10.3997/1873-0604.2017046, 2018.[2] R. Persico, I. Farhat, L. Farrugia, S. d&#8217;Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, doi.org/10.2113/JEEG23.4.437, 23 (4): 437-442, 2018.[3] R. Pierri, G. Leone, F. Soldovieri, R. Persico, "Electromagnetic inversion for subsurface applications under the distorted Born approximation" Nuovo Cimento, vol. 24C, N. 2, pp 245-261, March-April 2001.[4] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, vol. 12, n. 6, pp. 793-801 (doi: 10.3997/1873-0604.2014035), December 2014.[5] R. Pethig, "Dielectric Properties of Biological Materials: Biophysical and Medical Applications," in&#160;IEEE Transactions on Electrical Insulation, vol. EI-19, no. 5, pp. 453-474, Oct. 1984. doi: 10.1109/TEI.1984.298769&#160;[6] C. Gabriel,&#160;S. Gabriel&#160;and&#160;E Corthout, &#8220;The dielectric properties of biological tissues: I. Literature survey,&#8221; Physics in Medicine and Biology, vol. 41, no. 11, pp. 2231-2249, Nov. 1996.

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An Innovative Use of TDR Probes: First Numerical Validations with a Coaxial Cable

Journal of Environmental and Engineering Geophysics ◽

10.2113/jeeg23.4.437 ◽

2018 ◽

Vol 23 (4) ◽

pp. 437-442

Author(s):

Raffaele Persico ◽

Iman Farhat ◽

Lourdes Farrugia ◽

Sebastiano D'Amico ◽

Charles Sammut

Keyword(s):

Magnetic Properties ◽

Transmission Line ◽

Time Domain ◽

Numerical Data ◽

Time Domain Reflectometry ◽

Coaxial Cable ◽

Transmission Line Model ◽

Properties Of Materials

In this paper we propose a study regarding some possibilities that can be offered by a time domain reflectometry (TDR) probe in retrieving both dielectric and magnetic properties of materials. This technique can be of interest for several applications, among which the characterization of soil in some situations. In particular, here we propose an extension of the paper “Retrieving electric and magnetic propetries of the soil in situ: New possibilities”, presented at the IWAGPR, held in Edinburgh in 2017, and as a new contribution we will validate a transmission line model with numerical data simulated by the CST code.

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Structural and Magnetic Properties of Fe73,5Si13,5B9Nb3Cu1 Microwires Produced by Modernized Ulitovsky-Taylor Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.233-234.277 ◽

2015 ◽

Vol 233-234 ◽

pp. 277-280

Author(s):

Elena E. Shalygina ◽

Aleksander N. Shalygin ◽

Anna M. Kharlamova ◽

Vaycheslav V. Molokanov ◽

Tatiana R. Chueva ◽

...

Keyword(s):

Magnetic Properties ◽

High Strength ◽

Geometric Parameters ◽

Magnetic Characteristics ◽

High Plasticity ◽

Surface Layers ◽

Near Surface ◽

Structural And Magnetic Properties ◽

Taylor Method ◽

Amorphous Microwires

Results of the investigation of the mechanical, elastic and magnetic characteristics of the “thick” Fe73,5Si13,5B9Nb3Cu1 amorphous microwires, produced by the modernized Ulitovsky–Taylor method, are presented. The cores of the Fe73,5Si13,5B9Nb3Cu1 microwires were found to have the stable geometric parameters along their length and the smooth (almost without defects) surface. The microwires are characterized by the high plasticity and the high strength. The stable geometric parameters of the Fe73,5Si13,5B9Nb3Cu1 microwires along their lengths cause the slight dispersion of magnetic anisotropy of the near-surface layers. As a result, the microwires exhibit the high homogeneity of the near-surface local magnetic properties. The strong influence of the stretching and torsion tensions on the remagnetization signal of the microwires was discovered.

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First geophysical results in the Archeological sites of Θούρια (Péloponnèse, Hellas) and Sibari-Thurii (southern Italy)

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.16827 ◽

2018 ◽

Vol 40 (3) ◽

pp. 1080

Author(s):

B. Di Fiore ◽

D. Chianese ◽

A. Loperte ◽

G. Conte ◽

A. Dibenedetto ◽

...

Keyword(s):

High Resolution ◽

Information Quality ◽

Southern Italy ◽

Magnetic Measurements ◽

Early Stage ◽

Geophysical Methods ◽

Magnetic Data ◽

Near Surface ◽

Data Inversion ◽

Near Surface Geophysics

High resolution techniques for data acquisition and processing procedures are increasingly applied in near-surface geophysics for archaeology. In this paper we present the preliminary results of two geophysical measurements campaigns aimed to the investigation of buried remains in the archaeological sites of Θουρία (Péloponnèse, Hellas) and Sibari (Southern Italy). In the first field survey the geophysical approach involved the integrated application of the geoelectrical and magnetic methods and an innovative tomographic analysis for the inversion of both resistivity and magnetic data. In the second case, we carried out high resolution magnetic measurements, interpreted by means of the use of an appropriate filtering procedure. The applied data inversion allows us to provide reliable space patterns of the most probable specific target boundaries, improving the information quality of geophysical methods. The results obtained at this early stage of data processing confirm some archaeological hypothesis about the investigated areas and confirm that the use of integrated geophysical methods allows the archaeologists to reduce the time and the costs of their surveys.

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Multi-length probes in GPR and TDR data

10.5194/egusphere-egu21-16499 ◽

2021 ◽

Author(s):

Raffaele Persico

Keyword(s):

Coaxial Cable ◽

Single Frequency ◽

Near Surface ◽

Radio Science ◽

Independent Information ◽

Electromagnetic Characteristics ◽

Stepped Frequency ◽

Near Surface Geophysics ◽

University Of Florence ◽

The Cost

I will expose some possibilities regarding the use of metallic probes of different lengths in GPR and TDR prospecting. With regard to GPR, multi-length probes are dipole-like antennas whose length can be changed by means of switches. The switches can be implemented with PIN diodes, and can act as electronic &#8220;knifes&#8221;. Therefore, they allow to cut (switched off) or prolong (switched on) the branches of a couple of antennas, and this allows to have more couples of equivalent antennas making use of a unique physical couple of antennas. This allows to contain the size of the system. In particular, a reconfigurable prototypal stepped frequency GPR system was developed within the project AITECH (http://www.aitechnet.com/ibam.html) and was tested in several cases histories &#160;[1-3]. Within this reconfigurable GPR, it is also possible to reconfigure vs. the frequency the integration times of the harmonic tones constituting the radiated signal. This feature allows to reject external electromagnetic interferences without filtering the spectrum of the received signal [4] and without increasing the radiated power.With regard to TDR measurements, a multi-length probe consists of a TDR device where the rods (in multi-wire version) or the length of internal and external conductor (in coaxial version) can be changed. This can be useful for the measurements of electromagnetic characteristics of a material under test (MUT), in particular its dielectric permittivity and magnetic permeability, both meant in general as complex quantities. Multi-length TDR measurements allow to acquire independent information on the MUT even at single frequency, and this can be of interest in the case of dispersive materials [5-6].AcknowledgementsI collaborated with several colleagues about the above issues. To list of them would be long, so I will just mention their affiliations: Florence Engineering srl, University of Florence, IDSGeoradar srl, 3d-radar Ltd, Institute for Archaeological and Monumental Heritage IBAM-CNR, University of Bari, University of Malta. Finally, a particular mention is deserved for the Cost Action TU1208.References[1] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, 12, 793-801, 2014.[2] L. Matera, M. Noviello, M. Ciminale, R. Persico, Integration of multisensor data: an experiment in the archaeological park of Egnazia (Apulia, Southern Italy), Near Surface Geophysics, 13, 613-621, 2015.[3] R. Persico, S. D'Amico, L. Matera, E. Colica, C. De, Giorgio, A. Alescio, C. Sammut and P. Galea, P. (2019), GPR Investigations at St John's Co&#8208;Cathedral in Valletta, Near Surface Geophysics, 17, 213-229, 2019.[4] R. Persico, D. Dei, F. Parrini, L. Matera, Mitigation of narrow band interferences by means of a reconfigurable stepped frequency GPR system, Radio Science, 51, 2016.[5] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, 16,1-9, 2018.[6] R. Persico, I. Farhat, L. Farrugia, S. d&#8217;Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, 23, 437-442, 2018.&#160;

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Multi-length probes in GPR and TDR data

10.5194/egusphere-egu2020-7426 ◽

2020 ◽

Author(s):

Raffaele Persico

Keyword(s):

Coaxial Cable ◽

Single Frequency ◽

Near Surface ◽

Radio Science ◽

Independent Information ◽

Electromagnetic Characteristics ◽

Stepped Frequency ◽

Near Surface Geophysics ◽

University Of Florence ◽

The Cost

I will expose some possibilities regarding the use of metallic probes of different lengths in GPR and TDR prospecting. With regard to GPR, multi-length probes are dipole-like antennas whose length can be changed by means of switches. The switches can be implemented with PIN diodes, and can act as electronic &#8220;knifes&#8221;. Therefore, they allow to cut (switched off) or prolong (switched on) the branches of a couple of antennas, and this allows to have more couples of equivalent antennas making use of a unique physical couple of antennas. This allows to contain the size of the system. In particular, a reconfigurable prototypal stepped frequency GPR system was developed within the project AITECH (http://www.aitechnet.com/ibam.html) &#160;and was tested in several cases histories &#160;[1-3]. Within this reconfigurable GPR, it is also possible to reconfigure vs. the frequency the integration times of the harmonic tones constituting the radiated signal. This feature allows to reject external electromagnetic interferences without filtering the spectrum of the received signal [4] and without increasing the radiated power.With regard to TDR measurements, a multi-length probe consists of a TDR device where the rods (in multi-wire version) or the length of internal and external conductor (in coaxial version) can be changed. This can be useful for the measurements of electromagnetic characteristics of a material under test (MUT), in particular its dielectric permittivity and magnetic permeability, both meant in general as complex quantities. Multi-length TDR measurements allow to acquire independent information on the MUT even at single frequency, and this can be of interest in the case of dispersive materials [5-6].AcknowledgementsI collaborated with several colleagues about the above issues. To list of them would be long, so I will just mention their affiliations: Florence Engineering srl, University of Florence, IDSGeoradar srl, 3d-radar Ltd, Institute for Archaeological and Monumental Heritage IBAM-CNR, University of Bari, University of Malta. Finally, a particular mention is deserved for the Cost Action TU1208.References[1] R. Persico, M. Ciminale, L. Matera, A new reconfigurable stepped frequency GPR system, possibilities and issues; applications to two different Cultural Heritage Resources, Near Surface Geophysics, 12, 793-801, 2014.[2] L. Matera, M. Noviello, M. Ciminale, R. Persico, Integration of multisensor data: an experiment in the archaeological park of Egnazia (Apulia, Southern Italy), Near Surface Geophysics, 13, 613-621, 2015.[3] R. Persico, S. D'Amico, L. Matera, E. Colica, C. De, Giorgio, A. Alescio, C. Sammut and P. Galea, P. (2019), GPR Investigations at St John's Co&#8208;Cathedral in Valletta, Near Surface Geophysics, 17, 213-229, 2019.[4] R. Persico, D. Dei, F. Parrini, L. Matera, Mitigation of narrow band interferences by means of a reconfigurable stepped frequency GPR system, Radio Science, 51, 2016.[5] R. Persico, M. Pieraccini, Measurement of dielectric and magnetic properties of Materials by means of a TDR probe, Near Surface Geophysics, 16,1-9, 2018.[6] R. Persico, I. Farhat, L. Farrugia, S. d&#8217;Amico, C. Sammut, An innovative use of TDR probes: First numerical validations with a coaxial cable, Journal of Environmental & Engineering Geophysics, 23, 437-442, 2018.

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Electronic, Optical, and Magnetic Properties of Materials: A Comic-Based MOOC

2020 IEEE Learning With MOOCS (LWMOOCS) ◽

10.1109/lwmoocs50143.2020.9234344 ◽

2020 ◽

Author(s):

Jessica Sandland ◽

Emma Vargo ◽

Jonathan Paras ◽

George Varnavides ◽

Sarah Warkander ◽

...

Keyword(s):

Magnetic Properties ◽

Properties Of Materials ◽

Optical And Magnetic Properties

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Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications

Nanomaterials ◽

10.3390/nano11020341 ◽

2021 ◽

Vol 11 (2) ◽

pp. 341

Author(s):

Tien Hiep Nguyen ◽

Gopalu Karunakaran ◽

Yu.V. Konyukhov ◽

Nguyen Van Minh ◽

D.Yu. Karpenkov ◽

...

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Reduction Process ◽

Chemical Precipitation ◽

Precipitation Method ◽

Magnetic Characteristics ◽

Reduction Temperature ◽

Fe Content ◽

Magnetic Features ◽

Co Precipitation

This paper presents the synthesis of Fe–Co–Ni nanocomposites by chemical precipitation, followed by a reduction process. It was found that the influence of the chemical composition and reduction temperature greatly alters the phase formation, its structures, particle size distribution, and magnetic properties of Fe–Co–Ni nanocomposites. The initial hydroxides of Fe–Co–Ni combinations were prepared by the co-precipitation method from nitrate precursors and precipitated using alkali. The reduction process was carried out by hydrogen in the temperature range of 300–500 °C under isothermal conditions. The nanocomposites had metallic and intermetallic phases with different lattice parameter values due to the increase in Fe content. In this paper, we showed that the values of the magnetic parameters of nanocomposites can be controlled in the ranges of MS = 7.6–192.5 Am2/kg, Mr = 0.4–39.7 Am2/kg, Mr/Ms = 0.02–0.32, and HcM = 4.72–60.68 kA/m by regulating the composition and reduction temperature of the Fe–Co–Ni composites. Due to the reduction process, drastic variations in the magnetic features result from the intermetallic and metallic face formation. The variation in magnetic characteristics is guided by the reduction degree, particle size growth, and crystallinity enhancement. Moreover, the reduction of the surface spins fraction of the nanocomposites under their growth induced an increase in the saturation magnetization. This is the first report where the influence of Fe content on the Fe–Co–Ni ternary system phase content and magnetic properties was evaluated. The Fe–Co–Ni ternary nanocomposites obtained by co-precipitation, followed by the hydrogen reduction led to the formation of better magnetic materials for various magnetically coupled device applications.

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Microstructure and magnetic properties of Nd-Fe-B-(Re, Ti) alloys

Nukleonika ◽

10.1515/nuka-2015-0008 ◽

2015 ◽

Vol 60 (1) ◽

pp. 29-33

Author(s):

Mariusz Hasiak

Keyword(s):

Magnetic Properties ◽

Phase Composition ◽

Volume Fraction ◽

Magnetic Characteristics ◽

Ti Alloys ◽

Wide Range ◽

Magnetically Hard ◽

Ti Addition ◽

Microstructure And Magnetic Properties

Abstract The microstructure and magnetic properties of nanocomposite hard magnetic Nd-Fe-B-(Re, Ti) materials with different Nd and Fe contents are studied. The role of Re and Ti addition in phase composition and volume fraction of the Nd-Fe-B phase is determined. All samples are annealed at the same temperature of 993 K for 10 min. Mössbauer spectroscopy shows that the addition of 4 at.% of Re to the Nd8Fe78B14 alloy leads to creation of an ineligible amount of the magnetically hard Nd2Fe14B phase. Moreover, the microstructure and magnetic characteristics recorded in a wide range of temperatures for the Nd8Fe79−xB13Mx (x = 4; M = Re or Ti) alloys are also analyzed.

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