ePC-SAFT advanced - Part I: Physical meaning of including a concentration-dependent dielectric constant in the born term and in the Debye-Hückel theory

We describe the physical properties of a planar interface between an electrolyte and a charged lipid membrane. The model differs from the usual Gouy–Chapman–Debye–Huckel theory for electrolytes in that the dipolar nature of the water molecules is explicitly included. The polarization, dielectric constant, and electric potential of the electrolyte are calculated as functions of distance from the interface. The change in gel – liquid-crystal transition temperature is obtained as a function of pH and salt concentration from the free energy of the system. The results are compared to previous calculations using the Gouy–Chapman–Debye–Huckel theory and to experimental data for dimyristoyl-methylphosphoric acid.

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Discussion and Analysis of Dumbbell Defect-Ground-Structure (DB-DGS) Resonators for Sensing Applications from a Circuit Theory Perspective

Sensors ◽

10.3390/s21248334 ◽

2021 ◽

Vol 21 (24) ◽

pp. 8334

Author(s):

Lijuan Su ◽

Paris Vélez ◽

Jonathan Muñoz-Enano ◽

Ferran Martín

Keyword(s):

Dielectric Constant ◽

Transmission Lines ◽

Physical Meaning ◽

Parameter Extraction ◽

Circuit Theory ◽

Realistic Model ◽

General Assumption ◽

Ground Structure ◽

Sensing Applications ◽

Defect Ground Structure

Microstrip transmission lines loaded with dumbbell defect-ground-structure (DB-DGS) resonators transversally oriented have been exhaustively used in microwave circuits and sensors. Typically, these structures have been modelled by means of a parallel LC resonant tank series connected to the host line. However, the inductance and capacitance of such model do not have a physical meaning, since this model is inferred by transformation of a more realistic model, where the DB-DGS resonator, described by means of a resonant tank with inductance and capacitance related to the geometry of the DB-DGS, is magnetically coupled to the host line. From parameter extraction, the circuit parameters of both models are obtained by considering the DB-DGS covered with semi-infinite materials with different dielectric constant. The extracted parameters are coherent and reveal that the general assumption of considering the simple LC resonant tank series-connected to the line to describe the DB-DGS-loaded line is reasonable with some caution. The implications on the sensitivity, when the structure is devoted to operating as a permittivity sensor, are discussed.

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Microstructural characterization of YBaCuO Films on LaAlO3 substrates

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100152872 ◽

1989 ◽

Vol 47 ◽

pp. 180-181

Author(s):

E. L. Hall ◽

A. Mogro-Campero ◽

N. Lewis ◽

L. G. Turner

Keyword(s):

Dielectric Constant ◽

Single Crystal ◽

Film Growth ◽

Microstructural Characterization ◽

Lattice Parameter ◽

Film Plane ◽

Substrate Material ◽

High Loss ◽

Amorphous Substrates ◽

High Dielectric

There have been a large number of recent studies of the growth of Y-Ba-Cu-O thin films, and these studies have employed a variety of substrates and growth techniques. To date, the highest values of Tc and Jc have been found for films grown by sputtering or coevaporation on single-crystal SrTiO3 substrates, which produces a uniaxially-aligned film with the YBa2Cu3Ox c-axis normal to the film plane. Multilayer growth of films on the same substrate produces a triaxially-aligned film (regions of the film have their c-axis parallel to each of the three substrate <100> directions) with lower values of Jc. Growth of films on a variety of other polycrystalline or amorphous substrates produces randomly-oriented polycrystalline films with low Jc. Although single-crystal SrTiO3 thus produces the best results, this substrate material has a number of undesireable characteristics relative to electronic applications, including very high dielectric constant and a high loss tangent at microwave frequencies. Recently, Simon et al. have shown that LaAlO3 could be used as a substrate for YBaCuO film growth. This substrate is essentially a cubic perovskite with a lattice parameter of 0.3792nm (it has a slight rhombohedral distortion at room temperature) and this material exhibits much lower dielectric constant and microwave loss tangents than SrTiO3. It is also interesting from a film growth standpoint since it has a slightly smaller lattice parameter than YBa2Cu3Ox (a=0.382nm, b=c/3=0.389nm), while SrTiO3 is slightly larger (a=0.3905nm).

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Enhanced performance of supercapacitors by constructing a “mini parallel-plate capacitor” in an electrode with high dielectric constant materials

Journal of Materials Chemistry A ◽

10.1039/d0ta04364h ◽

2020 ◽

Vol 8 (32) ◽

pp. 16661-16668

Author(s):

Huayao Tu ◽

Shouzhi Wang ◽

Hehe Jiang ◽

Zhenyan Liang ◽

Dong Shi ◽

...

Keyword(s):

Dielectric Constant ◽

Carbon Fiber ◽

Parallel Plate ◽

Sandwich Structure ◽

High Dielectric Constant ◽

Parallel Plate Capacitor ◽

Plate Capacitor ◽

Fiber Metal ◽

High Dielectric ◽

Mini Plate

The carbon fiber/metal oxide/metal oxynitride layer sandwich structure is constructed in the electrode to form a mini-plate capacitor. High dielectric constant metal oxides act as dielectric to increase their capacitance.

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Ultrahigh Energy Storage Performances of Polymer-based Nanocomposite via Interfaces Engneering

Journal of Materials Chemistry A ◽

10.1039/d0ta10044g ◽

2020 ◽

Author(s):

Peng Wang ◽

Zhongbin Pan ◽

Weilin Wang ◽

Jianxu Hu ◽

Jinjun Liu ◽

...

Keyword(s):

Dielectric Constant ◽

Energy Storage ◽

High Performance ◽

Breakdown Strength ◽

Composite Films ◽

Power Electronic ◽

Ultrahigh Energy

High-performance electrostatic capacitors are in urgent demand owing to the rapidly development of advanced power electronic applications. However, polymer-based composite films with both high breakdown strength (Eb) and dielectric constant...

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