Effect of  Nb5+ and In3+  Ions on Moisture Sensitivity of Electrospun Titanium/Tungsten Oxide Nanostructures: Microstructural Characterization and Electrical Response

In this work, Nb5+ and In3+ ions were used as dopants in titanium/tungsten oxide nanostructures that are produced by the electrospinning and sintering process, for relative humidity (RH) detection. The microstructural properties were investigated by SEM, EDS, XRD, Raman and FTIR techniques. The electrical response characterization of the samples was performed by electrical impedance spectroscopy in the range of 400 Hz to 40 MHz, at 20 °C. The sensors sensitivity to moisture was evaluated in terms of the impedance variations to RH (10–100%). The combined analysis of the microstructural characterization results confirmed the surface interaction between the oxides and the ions incorporation in Ti crystal lattice. All the studied sensors showed a conduction transition from p- to n-type at around 30–40% RH: besides, they also displayed better sensitivity to moisture than those obtained in a previous work using titanium/tungsten combination using a different fabricationn route. The impedance modulus variation up to 1.1 and 1.3 orders of magnitude for the 4 wt % niobium and indium doped samples, respectively. The results are directly associated with the microstructure and alternative preparation process.

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Electrical impedance spectroscopy for the characterization of skin barrier in atopic dermatitis

Allergy ◽

10.1111/all.14842 ◽

2021 ◽

Author(s):

Arturo O. Rinaldi ◽

Angelica Korsfeldt ◽

Siobhan Ward ◽

Daniel Burla ◽

Anita Dreher ◽

...

Keyword(s):

Atopic Dermatitis ◽

Impedance Spectroscopy ◽

Electrical Impedance ◽

Skin Barrier ◽

Electrical Impedance Spectroscopy

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Electrical Impedance Spectroscopy for Monitoring Chemoresistance of Cancer Cells

Micromachines ◽

10.3390/mi11090832 ◽

2020 ◽

Vol 11 (9) ◽

pp. 832

Author(s):

Lexi Crowell ◽

Juan Yakisich ◽

Brian Aufderheide ◽

Tayloria Adams

Keyword(s):

Impedance Spectroscopy ◽

Cancer Cells ◽

Cancer Cell ◽

Cellular Response ◽

Electrical Impedance ◽

Electrical Impedance Spectroscopy ◽

Cell Behavior ◽

Drug Resistant ◽

Cancerous Cells

Electrical impedance spectroscopy (EIS) is an electrokinetic method that allows for the characterization of intrinsic dielectric properties of cells. EIS has emerged in the last decade as a promising method for the characterization of cancerous cells, providing information on inductance, capacitance, and impedance of cells. The individual cell behavior can be quantified using its characteristic phase angle, amplitude, and frequency measurements obtained by fitting the input frequency-dependent cellular response to a resistor–capacitor circuit model. These electrical properties will provide important information about unique biomarkers related to the behavior of these cancerous cells, especially monitoring their chemoresistivity and sensitivity to chemotherapeutics. There are currently few methods to assess drug resistant cancer cells, and therefore it is difficult to identify and eliminate drug-resistant cancer cells found in static and metastatic tumors. Establishing techniques for the real-time monitoring of changes in cancer cell phenotypes is, therefore, important for understanding cancer cell dynamics and their plastic properties. EIS can be used to monitor these changes. In this review, we will cover the theory behind EIS, other impedance techniques, and how EIS can be used to monitor cell behavior and phenotype changes within cancerous cells.

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Electrical Impedance Spectroscopy: “First Principles” analysis and simulations of electrical response in the classical range of frequencies below 1 THz and the resulting new role of Electrical Impedance Spectroscopy in electrical characterisation within Condensed Matter Physics

Pure and Applied Chemistry ◽

10.1515/pac-2018-1107 ◽

2019 ◽

Vol 91 (11) ◽

pp. 1837-1856 ◽

Cited By ~ 1

Author(s):

Petr Viščor ◽

Martin Viščor

Keyword(s):

Impedance Spectroscopy ◽

Electrical Impedance ◽

Electrical Response ◽

Condensed Matter ◽

Electrical Impedance Spectroscopy ◽

Classical Electrodynamics ◽

Condensed Matter Physics ◽

Full Potential ◽

Ion Conductor ◽

Linear Parabolic Equations

Abstract In order to investigate the full potential of the Electrical Impedance Spectroscopy (EIS) when used to address various aspects of conductive and dielectric response within the field of Condensed Matter Physics and Electrochemistry, a new analysis of the electrical impedance experiments has been undertaken. Within the framework of quantum mechanical band structure and using the concept of electrochemical potential for each of the relevant energies, the problem of electrical response in condensed phase has been formulated, using augmented Maxwell equations of Classical Electrodynamics, as a boundary value problem of a set of coupled, non-linear parabolic equations in energy, space and time. The result of this numerical analysis is a principal possibility of a complete electrical characterisation of both monocrystals, glassy solids and liquids. The EIS has been put in this way on a new qualitative level and should be considered now as the most general electrical experimental characterisation tool available. In this article, a methodology of numerical simulations of electrical response in condensed matter systems at classical frequencies (from ~1 THz down to dc) is presented and the numerical simulation results are then discussed, using monocrystalline Silicon, chalcogenide glass ion conductor Agx(AsS2)1−x and simple aqueous chloride solution as experimental test cases. Some other unique results of the new EIS analysis will also be discussed. These include the possibility of a clear distinction between the contribution to the electrical response from bound and mobile electrical charges, the possibility of simultaneous and independent determination of the mobile electrical charges mobility and their density in one EIS experiment and incorporation of the interfacial regions of the system under test (SUT) as an essential part of the overall electrical response.

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Microwave Assisted Blending-Intercalation of Ion-Conductor Polymers into Layered Silicates

MRS Proceedings ◽

10.1557/proc-519-375 ◽

1998 ◽

Vol 519 ◽

Cited By ~ 4

Author(s):

P. Aranda ◽

J.C. Galván ◽

E. Ruiz-Hitzky

Keyword(s):

Electrical Impedance ◽

Polymer Melt ◽

Electrical Impedance Spectroscopy ◽

Layered Silicates ◽

Alternative Procedure ◽

Ion Conductor ◽

Microwave Assisted ◽

Poly Ethylene Oxide ◽

Poly Ethylene

AbstractOrgano-inorganic hybrid nancomposites derived from poly(ethylene oxide) and montmorillonite silicate are prepared by an alternative procedure to classical polymer intercalation either from solutions or by polymer melt-intercalation. XRD, FTIR, DSC, elemental microanalysis and SEM techniques are applied for structural characterization of the resulting materials. The electrical properties of these nanocomposites are studied by means of the electrical impedance spectroscopy (EIS) showing enhanced ionic conductivity compared to similar samples prepared by intercalation from solution.

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