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Showing 1 to 20 of 21 for “"relative permittivity"”.
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Predicting surface water profiles in sand
… the EM wave is slowed through that material. The relative permittivity (dielectric constant) of a material is a measure of a material's ability to hold a charge. Knowing the relative permittivity enables one to calculate the velocity of an EM wave through the material. The goal of a larger …
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Microwave Overlay Capacitor Fabrication on Printed Circuit Boards
… electrical characterization. This is due to relative permittivity changing with frequency. The BST composite film recipes were developed using commercial powder and two types of polymer. An existing recipe using cyclic olefin copolymer (COC) was adapted for spray coating, while a new recipe …
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Evaluation of microwave microscopy for dielectric characterisation
… image charge model for the measurement of the relative permittivity of bulk samples is demonstrated.
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Soft nanocomposites with enhanced electromechanical response for dielectric elastomer actuators
… improving their properties are increasing the relative permittivity of the active material, while maintaining high electric breakdown strength and low stiffness, which would lead to enhanced electrostatic storage ability and hence, reduced operating voltage. Improvement of the functional …
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Resonant sensors for passive, real-time, and wireless characterization of biological analytes
… spiral sensors respond to any change in relative permittivity of the medium in contact with the resonator. This response is represented as a clear shift in the resonant frequency of the resonator. For instance, changing the medium from air to water results in approximately 50MHz redshift …
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Size reduction of vivaldi antenna array for microwave imaging
… is designed using FR-4 substrate which has relative permittivity of 4.3. and thickness of 1.6 mm. Furthermore, the single element is investigated to cover an ultra-wideband from 3.1 to 10.6 GHz by using Computer based Simulation Technology for Microwave studio (CST MWS) reducing the size of …
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Design and analysis of a frequency reconfigurable antenna for wireless communication at 5 GHz
… the industry standard FR- 4 material, with a relative permittivity of 4.3. The operational frequency bands for the designed antenna are 5 GHz and 7 GHz. The directivity obtained for all operational modes were above 6 dBi, while the return losses were above -25 dB. In addition, the simulated …
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INTERFACES IN THIN-FILM SOLID-STATE BATTERIES
… operation under different states-of-charge. Relative permittivity values of fundamental battery components (cathode, electrolyte and anode) were calculated as a function of the frequency and the applied voltage. Interfacial impedances, as well as space-charge layers formed at heterojunctions …
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Electrolyte Structure with Explicit Solvent in Nanoslit Capacitors using Classical Density Functional Theory
… This method allows us to construct a local relative permittivity that is a function of the molecular interactions. Using this model, we study the effects of solvent properties, temperature, surface charge, and slit geometry on the adsorption and structure of each component. This model can be …
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Miniaturized Antenna for Satellite Broadband Application
… grating lobes. A novel dielectric material with relative permittivity of 5.7 is coated on the MEDA to significantly reduce the size of the antenna without disrupting its broadband characteristics, to make the MEDA compatible with planar array configuration. The miniaturized antenna element is …
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A Characteristic Mode Analysis of Conductive Nanowires and Microwires Above a Lossy Dielectric Half-Space
… modes are weighted by two coefficients: (i) the relative importance of each mode at a certain frequency, termed Modal Significance, and (ii) the level of coupling between the incident field and the mode termed the Modal Excitation Coefficient. In this, work we study how the wire’s material affect …
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Graded ferroelectric devices: the dielectric analogues of semiconductor diode junctions
… by metallorganic decomposition (MOD). The relative permittivity, dissipation, polarization, resistivity, and grain size were studied as a function of composition and temperature. Ferroelectric hysteresis loops were observed for all values of x and were found to be independent of measurement …
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Preparation and characterization of lead lanthanum titanate thin films by metalorganic decomposition
… in the Pb-based perovskite family have high relative permittivities and have consequently attracted a world wide attention. Cubic Lead Lanthanum Titanate (PLT) is one of the prime candidates in this respect and its structure and properties in the thin film form were investigated in the …
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Impedance Sensors for Fast Multiphase Flow Measurement and Imaging
… evaluated. The first one is a complex permittivity needle probe which can detect the phases of a multiphase flow at its probe tip by simultaneous measurement of the electrical conductivity and permittivity at up to 20 kHz repetition rate. Two-dimensional images of the phase distribution …
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Optimisation of silicone-based dielectric elastomer transducers by means of block copolymers – synthesis and compounding
… silicone and subsequently cross-linked. The relative permittivity of cross-linked silicone with 5 wt% of PDMS-PEG copolymers increased by nearly 50%, without compromising dielectric loss and mechanical properties, compared to the commercial silicone elastomer. The second investigated method …
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Planar groove gap waveguides
… loss variation implemented on a substrate of relative permittivity r of 3.5, and loss tangent of 0.004. The broadband characterization of the transmission line loss and phase constant for PGGWG at Ka-band shows that PGGWG has comparable attenuation over the band of interest to SIW. The …
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Ink jet printing of PZT thin films for MEMS
… and -95pC/N. Impedance data at 1kHz provided the relative permittivity (750-890) and the dielectric loss tangent (2.4%-2.8%). The final printing process enabled the first digital deposition of thin film PZT and the printed PZT based pMUT confirmed the properties of the film are within the range …
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Dual parametric sensors for highly sensitive nucleic acid detection
… 10- mer nucleotide sequences. A 30-40% change in relative permittivity (capacitance) was observed due to DNA hybridization at 10Hz, which is much more sensitive than the previously reposted detection measurements (2-8% signal change). In parallel to the above work, a second label-free sensing …
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Simulation of Simultaneously Negative Medium Metamaterials
… existing documentation, the metamaterials have relative permittivity and/or relative permeability of values less than 1, including negative values. If the material has negative permittivity and permeability at the same time, the material is also referred to as simultaneously negative medium (DNG …
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Advanced Polymeric Membranes and Multi-Layered Films for Gas Separation and Capacitors
… and symmetry on Tg, breakdown strength, and relative permittivity was investigated. A systematic series of four amorphous poly(arylene ether ketone)s was compared. Two of the polymers had symmetric bisphenols while the remaining two had asymmetric bisphenols. Two contained trifluoromethyl …
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