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In this article, a novel (22×22×0.8 mm3) tree-shaped microstrip patch antenna with dual operating bands is presented for satellite applications. The proposed design (A4) was drawn on low-cost Roger dielectric substrate (εr = 4.4, tan = 0.02 and h = 0.8), and proposed antenna has return loss below -10 dB at both exhibited bands, and finding that the first operating band has impedance bandwidth of 35.22 % (15.72-22.44 GHz), resonating frequency of 15.95 GHz with 5.8 dBi peak gain and second operating band has impedance bandwidth of 22.84% (22.44-28.23 GHz), resonating frequency of 19.30 GHz with 6.20 dBi peak gain are obtained respectively. The proposed antenna has a VSWR between 1 and 2 and a group delay time between -0.60 and 0.40 nanoseconds (<0.5 ns). HFSS simulation initiatives included in ANSOFT version 13 were used to evaluate the proposed antenna design and model. [ABSTRACT FROM AUTHOR]

This article explains how to create a microstrip patch antenna using material loading. It is well known that over the past four decades, researchers have thoroughly investigated a microstrip patch antenna from every imaginable perspective. In this study, a dielectric substrate with a conducting patch printed on it is used to create an antenna. The patch is placed onto a ground plane once its construction is complete. It is valuable for a variety of reasons, one of which being the ease with which it may be produced or created. It is advantageous in a number of additional ways, which is one of the other reasons. It's constructed with a smooth surface and a low profile when it is designed. When using components from a circuit, the building procedure is relatively straightforward and uncomplicated. The microstrip patch antenna has a minimum dimension requirement that is approximately equivalent to one-half of a wavelength. The adoption of new standards within the wireless sector, in addition to the development of more compact wireless devices, was directly responsible for the decrease in size of this antenna. This study focuses in particular on material loading procedures that have been published in the prior body of research with the intention of reducing the size of the footprint that is occupied by a microstrip patch antenna. This study was carried out with the intention of reducing the size of the footprint. [ABSTRACT FROM AUTHOR]

We focus on the conductivity analysis of Aurivillius family of six-layered intergrowth compound, namely Bi7Ti4NbO21. The compound was prepared by solid state intergrowth route. The product compound belongs to orthorhombic structure and the lattice parameters were found to be: (a = 5.442 A0, b = 5.404 A0, c = 57.990 A0). The frequency dependent impedance measurements were made on the sample over a frequency range of 100 - 1MHz, right from room temperature to 500°C. A detailed study on ac-conductivity and complex impedance analysis was carried out on the said above intergrowth compound. The depressed and asymmetric semicircles of Cole-Cole plots suggest that the charge carriers are of non-Debye (multiple) type. The charge carriers were found to be controlled by thermally-activated process. Temperature dependent ac-conductivity data show change of slopes in the vicinity of intermediate and higher frequency domain. Finally, results were corroborated to the dielectric and FTIR data. [ABSTRACT FROM AUTHOR]

In modern photonics, the calculation of effective optical properties of composite materials is of significant interest because it allows to predict the characteristics of the resulting material and provides a deeper understanding of the basic physical processes. There is no doubt that any research performed in this field is greatly Interesting as numerous aspects still remain enigmatic. The present article considers a multicomponent nanodispersed structure consisting of randomly oriented ellipsoidal nanoparticles in a matrix with a permittivity εm. Using the Maxwell-Garnett and Bruggeman models, the dependence of the effective dielectric permittivity of such a structure on the orientation of particles in an external field and the coefficient of volume filling of the medium with particles was studied. [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte [SPE] blend incorporating Poly (ethylene-oxide) and poly (vinylidene fluoride-co-hexafluoropropylene) [PEO/PVDF-HFP] and different wt.% of potassium trifluoromethanesulfonate (KCF3SO3) was composed. The SPE blend containing 20% of KCF3SO3 presents highest ionic conductivity of 4.28×10-6 Scm-1, which is observed to increase due to addition of titanium oxide nanoparticles (TiO2) (10nm size). The conductivity increases to 7.95×10-5 Scm-1, for 5 wt.% of TiO2. The decline in relaxation time τ of ions from dielectric studies reveal an increment in disordered phase in the matrix. The observed decrease in glass transition and melting temperatures [Tg and Tm] in Differential Scanning Calorimeter (DSC) analysis also supports the observed increment in amorphous phase due to incorporation of nano particles. [ABSTRACT FROM AUTHOR]

There has been a lot of research on the potential of passive photonic devices, such dielectric reflectors, to supplant semiconductor technology in electronics. Intelligent windows, visual light communication enhancers, and UV radiation shields made of dielectric reflectors with the required stop band are in great demand. It is first of its kind to find a single way to calculate the ideal wavelength spectrum of a dielectric reflector. Here we provide a new way to produce dielectric reflectors in the range of wavelengths that you choose. By using XRD to examine the manufactured reflectors, the anatase phase of TiO2 inside the multilayer structure was exposed. examination using cross-sectional FE-SEM showed periodic bright (TiO2) and dark (SiO2) bands, and examination of film thickness showed that the produced films' film thickness may be reduced by increasing the spin rate. Reflectance measurements taken of the constructions also showed that the reflectance band may be shifted to lower wavelengths by making the multilayer structure's film thicker. [ABSTRACT FROM AUTHOR]

The present study investigated the degradation of methylene blue (MB) using a dielectric barrier discharge (DBD) plasma reactor. The reactor used models of a mesh-copper wire configuration and was generated by High Voltage Alternating Current. Some analysis parameters included the voltage variation from 4–8 kV and the air flowrate from 0.4, 0.6, 0.8, and 1 L/min. The results revealed that the reactor could produce the highest ozone concentration, precisely 432 ppm, at a voltage of 8 kV and a flow rate of 0.4 L/min for 5 minutes. Further, the ozone in this condition was used to degrade methylene blue (MB) solution. The effects of DBD plasma with variations in treatment time of 0, 5, 10, 15, and 30 minutes on pH and concentration of MB were evaluated using pH meter and UV-Visible spectrophotometer, respectively. Based on the experiment results, the efficiency of MB degradation was 61,84 % at 30 minutes of treatment. [ABSTRACT FROM AUTHOR]

Fast curing epoxy resins processed in liquid composite moulding (LCM) enable to shorten the cycle time by accelerating the curing process and therefore provide a high potential for cost-efficient high production volumes in the automotive industry. To meet the target of reducing the in-mould time, a precise monitoring of the curing reaction and transition phenomena such as gelation or vitrification is required. In the present study, simultaneous rheometer measurements and dielectric analysis (DEA) are performed to provide a correlation between rheological and dielectric data to determine gelation time. Subsequently, the transferability of these criteria to in-situ measurements and process-specific pressures up to 10 MPa is investigated. To model the reaction kinetics two different approaches are selected to predict the degree of cure reached at gelation. A simple autocatalytic and a diffusion-controlled approach are selected to overcome premature vitrification before the maximum degree of cure is reached. Model parameters are fitted based on isothermal DEA measurement, as this case is particularly relevant, since deviations can result from cross-linking not included at the beginning of the isothermal measurement. The results show the potential for in-line measurement of process-specific data during the crosslinking of fast-curing epoxy resins and represent an essential prerequisite for DEA based quality control and quality assurance in industrial scale LCM processes. [ABSTRACT FROM AUTHOR]

The main objective of this research was to evaluate plasma parameters utilizing dielectric barrier discharge (DBD) plasmas with varying excitation voltages of 4 kV, 6 kV, and 8 kV. The optical emission spectra of an Ar/O2 plasma created at constant frequency and flow rates for different voltages ranging from 4 kV to 8 kV demonstrated that voltage fluctuations induced a considerable difference in the intensity of the Ar/O2 emission. The electron temperature (Te) and electron density (ne) were measured using the Boltzmann plot and Stark broadening, respectively. The electron temperature (Te) rises as the voltage increases from 1.47 eV to 1.62 eV. Furthermore, with rising voltages, the Debye length (λD) decreases while the electron density (ne), plasma frequency (fp), and number of particles in the Debye sphere (ND) increase. [ABSTRACT FROM AUTHOR]

One of the electrical discharge machining purposes today, mainly nanopowder mix electrical discharge machining, is to get high-quality surface integrity materials. The input process parameters must be adjusted as needed to get good results. The current work includes an experimental study of the effect of discharge current, pulse on time (Pon), pulse off time (Poff), powder concentration, and mixing ratio of Al2O3 − graphite nanopowder on SR-surface roughness, EWR-electrode wear rate and MRR-material removal rate, during electrical discharge machining (EDM) of 304L stainless steel. A cylindrical copper electrode with a diameter of 16 mm and a length of 40 mm was employed as a tool electrode in this unconventional machining procedure. MINITAB 18 half factorial design of the experiment method was used by considering 5 factors and 5 levels. Total tests-24 tests (12 tests for conventional EDM and 12 tests for NPMEDM) were carried out with various combinations of input elements. The results showed that adding alumina-graphite nanoparticles to an EDM kerosene dielectric had a more significant influence on increasing the MRR and decreasing the EWR and SR. This work investigates the possibility of dielectric modification by adding Al2O3-graphite nanopowder to enhance performance during machining. The performance of this developed nanopowder-mixed electrical discharge machining (NPMEDM) method is compared with conventional EDM. The mean value of MRR rises from 0.1263 to 0.1383 g/min, EWR drops from 0.0066 to 0.0052 g/min, and SR increases from 5.131 to 4.939 µm. [ABSTRACT FROM AUTHOR]

Transformers are among the most expensive items among power system apparatus, and they plays a crucial role in the resulting power systems. Oil-impregnated paper (OIP) bushings form a key part of many transformers, and the status of these bushings may thus affect transformer performance. Monitoring OIP bushings is thus important for the safe operation of transformers, and one of the factors that can negatively affect OIP bushings is moisture. Effective evaluation of moisture in OIP bushings is thus required to ensure the safe operation of power systems. The dielectric frequency response (DFR) method has been commonly used in the last decade to study moisture impacts on OIP bushings. In this study, however, the moisture level in OIP bushings was evaluated using a neural network trained on a database formed from previous DFR results for various OIP bushings. Using the finite element method (FEM), a 96 kV OIP bushing was simulated under six different moisture content levels. Statistical indices were then used to extract features from the obtained tanδ-f curves of the simulated bushing under these different moisture contents, with, fitting analysis used to generate additional data. A database was then established using the generated data, and a neural network proposed to categorise the database into three groups based on moisture levels. The results revealed that the neural network effectively categorised 99.5% of data correctly by moisture level, suggesting that an adequately tuned neural network can be used to evaluate the moisture level of OIP bushings. [ABSTRACT FROM AUTHOR]

In this growing world, development is accompanied by ever-increasing energy demand and storage. Capacitors are the most useful and promising devices for energy storage. In this paper, we compare the performance of TiO2, BaTiO3, and their composites as dielectrics for capacitor application. For this purpose, we fabricated, analyzed, and compared the single oxide ceramics and their composite forms, which are made by adding 10%, 20%, and 30% of BaTiO3 to TiO2. The structural analysis was done via x-ray diffraction, and to procure the I-V (current-voltage) plots and C-V (capacitance-voltage) (at 10 kHz), hysteresis inquisition has been carried out and utilized. From the result, it is concluded that TiO2 and BaTiO3 and their composites possess high dielectric constants and have good interface quality with leakage current density, of which 30%BaTiO3/TiO2 composite possesses the most desirable values. The study unveils the increased dielectric property of the BaTiO2/TiO2 composite and adds a new member to the dielectric capacitor family in the energy-storing field. [ABSTRACT FROM AUTHOR]

Electro-discharge machining is one of the most commonly used non-conventional machining methods in all industrial applications. Unfortunately, the widely used dielectrics are still carbon-based, which has a negative impact on the environment and operator. In the literature, it can be observed that the emphasis is also placed on improving the EDM process while using more environmentally friendly dielectrics. There are a few possible alternatives and process modifications to conduct the EDM process, reducing the generation of toxic particles, fumes, and gases, among which dry EDM can be highlighted. In the paper, the current state-of-the-art and future directions of development of dry and near-dry EDM have been presented. [ABSTRACT FROM AUTHOR]

The dielectric characteristics of heat – resistant synthetic foams based on cenospheres (floating fly ash particles of thermal power plants) and a heat-resistant binder based on linear aromatic polyamide-poly-m-phenylenizophthalamide were studied. Syntactic foams were prepared by mixing cenospheres with a solution of poly-m-phenylenizophthalamide in dimethylacetamide, forming the samples at a pressure of 0.5 MPa and then heat treatment at 1600C. The dielectric characteristics were measured by the waveguide method in the microwave radio range on a specialized laboratory stand consisting of a precision measuring line P1-20, a microwave module on a Gann diode, a ferrite valve and a standard rectangular waveguide with a cross section of 23*10 mm with a sample placed inside. The values of the permittivity and the tangent of the dielectric loss angle at the frequencies of 8-12 GHz are calculated. The dependences of the dielectric characteristics on the frequency and content of the components in the syntactic foam are obtained. It is found that with an increase in the polymer content, an increase in the dielectric constant and the tangent of dielectric losses at frequencies from 8 GHz to 12 GHz is observed. [ABSTRACT FROM AUTHOR]

The multiferroic composite, 0.10BaTiO3−0.90Ba0.9Ca0.1Fe12O19 investigated in the current study was synthesised by a solid-state reaction technique. The Powder X-ray Diffraction and Rietveld Refinements are used to validate successful composite synthesis and phase development. The composite consists of barium titanate (BT), which serves as the ferroelectric phase, and BaM (M-type barium hexaferrite) doped with Ca (BaCaFO), which serves as the ferromagnetic phase. The low-frequency behaviour of the dielectric constant (ε') and the dielectric loss (tan) is explained by referring to Maxwell-Wagner interfacial polarisation and Koop's two-layer model. The M-H loop illustrates the composite's magnetism. In accordance with the law of approaching saturation (LAS), the magnetization at saturation is calculated to be 70.33 emu/g. [ABSTRACT FROM AUTHOR]

Dielectric materials which capable to store charges are constantly being developed and improved for electronic applications such as in microelectronic integrated circuits (ICs). In this study, polylactic acid (PLA)/multiwalled carbon nanotube (MWCNT) composites are prepared and their dielectric properties are investigated. PLA/MWCNT composites have PLA as the matrix and MWCNT as filler with a loading of 1 wt%. The composites are porous composites achieved by using solvent casting and particulate leaching (SCPL) method. A frequency range of 1 kHz to 1 MHz is applied to measure the dielectric properties at room temperature. The PLA/MWCNT composites are categorized as low-k dielectric materials looking at the results of the dielectric test. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharges (DBD) can be described as the presence of contact with the discharge of one or more insulating layers located between two cylindrical or flat electrodes connected to an AC/pulse dc power supply. In this work, the properties of the plasma generated by dielectric barrier discharge (DBD) system without and with a glass insulator were studied. The plasma was generated at a constant voltage of 4 kV and fixed distance between the electrodes of 5 mm, and with a variable flow rate of argon gas (0.5, 1, 1.5, 2 and 2.5) L/min. The emission spectra of the DBD plasmas at different flow rates of argon gas have been recorded. Boltzmann plot method was used to calculate the plasma electron temperature (Te), and Stark broadening method was used to calculate the electron density (ne). [ABSTRACT FROM AUTHOR]

The crystalline sample of PbNb2O6 (Lead meta niobate or PN) was grown by solid-state reaction method. The material crystallizes in an orthorhombic structure at room temperature and its phase transition temperature was confirmed by hysteresis loop studies reported in our previous paper. The dielectric relaxation properties are investigated here for this material, in a temperature range from 27°C to 600°C in the frequency range (10 – 106 Hz). A supportive study of micro-structural features of the sample has been reported to confirm the mechanism of dielectric relaxation processes and relaxation kinetics. It is concluded that the dielectric relaxations occurring at low frequency are related to the presence of space charges in association with vacancies, which are trapped at the grain boundaries. [ABSTRACT FROM AUTHOR]

This article reports the preparation of sulfonated polyaniline emerald salt (PANI-ES) by a chemical oxidation process using ammonium persulfate as the oxidant and H2SO4 as the dopant. We first synthesize polyaniline/Ba(OH)28H2O composites with different weight percentages (10–35%) of BaOH content by in situ polymerization method and characterize them by spectral methods SEM, PXRD, and FTIR. The morphology of the PANI/BaOH (10% & 35%) composites shows that nanorods and nanoparticles were observed, respectively. PXRD studies show that the composites are crystalline. Assigned bonds from FTIR spectrograms indicate the formation of PANI/BaOH composites. The dielectric behaviour of PANI/BaOH was examined in frequency range from 100 Hz - 100 KHz and at room temperatures of 25°C and 70°C. Parameters of capacitance, dielectric constant, dielectric loss, and dissipation factor were calculated. Even at low BaOH contents, high scattering with a permittivity ξ' is observed, especially in the low-frequency range, while a sharp increase in ξ' and ξ" is seen at high BaOH concentrations. At this critical load, the electrical conductivity increases dramatically. [ABSTRACT FROM AUTHOR]

A comprehensive study on the behavior of gate-all-around (GAA) Tunnel Field Effect Transistors (TFET) with different dielectrics in single dielectric-based structure as well as stacking structure is reported. The gate-all-around structure is chosen so to have better gate control over the channel ensuing better characteristics of the device for the analog parameters investigated. To get the full benefit out of the device, the most optimized value of work-function is chosen. For single dielectrics-based GAA-TFETs, HfO2 outshines all the other dielectrics with ION of 4.34 µA and threshold voltage of 612mV. Furthermore, for the stacking structure, the duo of SiO2-HfO2 aces over the others with ION of 2.74 µA and threshold voltage of 613mV. Moreover, the low OFF-state current and sufficient drive current in stacked structure makes GAA-TFET a suitable contender for low power applications like mobile computing. [ABSTRACT FROM AUTHOR]

In this work, (90)KBiFe2O5−(10)CoFe2O4 [KBFO(90)-CFO(10)] composite is synthesized in polycrystalline form following the sol-gel technique. The magnetic, dielectric, and signature of the magnetodielectric (MD) effect in the prepared composite is verified over a wide temperature range. The phase purity of the prepared KBFO-CFO composite is confirmed by the room temperature (RT) X-Ray diffraction technique. The RT magnetization study reveals the weak ferromagnetic nature of the composite. The dielectric study reveals an anomaly near 500 °C, expected to be a structural phase transition. The magnetic anomaly near the dielectric transition suggests the signature of the MD coupling of the composite. The composite's indirect band-gap of 1.01 eV made it suitable for technological applications. Finally, the prepared composite shows the signature of the MD effect, and the low band gap suggests it is ideal for photovoltaic applications. [ABSTRACT FROM AUTHOR]

We have reported theoretical study the effect of different dielectric environment on surface roughness induced scattering rate for double layer graphene structure DLGS. Our results suggest that the effect of dielectric environment on SRP is remarkable. We have shown that to have unperturbed conductivity with respect to changing interlayer distance between two graphene layers in DLGS, one should choose middle layer such that its dielectric constant is the same or very close to that of substrate material. [ABSTRACT FROM AUTHOR]

The structure and dielectric properties of 6% Sr2+-substituted, modified Lead Zirconium Titanate (PZT) piezoelectric ceramic, with composition [Pb0.94Sr0.06][(Mn1/3Sb2/3)0.05(Zr0.54Ti0.46)0.95]O3 and lead manganese antimonite as an additional dopant, synthesized by ceramic route have been investigated in a frequency range from 50Hz to 1MHz and in a temperature range between room temperature and 633K. The scaling behavior of imaginary part of the electric modulus suggests that the relaxation is described by the same mechanism at various temperatures. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biodegradable and biocompatible polymer potentially applicable in biomedical terrain. While substantial progress is demonstrated in studying the biodegradability of PLA, there is a lack of scientific data regarding its dielectric properties in literature, for its holistic development as a complex green dielectric material. Considering the exceptional electrical and antimicrobial properties of graphene oxide (GO), PLA/GO composites were prepared using the injection molding technique. To overcome the shortcomings, the dielectric constant and ac conductivity of GO, neat PLA and PLA/GO composites were investigated at room temperature at 26°C with variations in frequency from 1Hz to 1MHz. Interestingly, it was shown that GO possessed a giant dielectric constant in the order of 105 at 1Hz, and consequently, the dielectric properties of neat PLA dramatically increased. The measured values are fitted using the modified Debye's expression and the fitting parameters evaluated. [ABSTRACT FROM AUTHOR]

Material technology for the manufacture of airframe structures is currently experiencing significant developments. The selection of materials for unmanned aircraft vehicles (UAV) is considered not only mechanical factors but also the electrical properties of the materials from electromagnetic interference, which can reduce aircraft performance. Materials with electromagnetic interference shielding depend on several parameters, such as electrical conductivity, dielectric permittivity, and magnetic permeability. This study aims to investigate several materials, such as carbon epoxy, hybrid E-glass carbon, E-glass 135, kevlar, kevlar carbon, and copper plate. Also, the dielectric value of each material and to analyze the parameters which best material to be used as Eelectromagnetics shielding and can be applied to UAV structures. The study was conducted by using a specimen material with a dimension of 10 x 4.5 cm and an average thickness of around 2.5 mm, then the sample was measured using dielectric Probe 85070, Agilent Technologies, E8364C. Frequency operation was used in the range of 900 MHz to 9 GHz. It can be seen that the highest dielectric constant composites materials were Carbon Epoxy materials and the lowest was E-Glass 135 Composites Materials. [ABSTRACT FROM AUTHOR]

Single crystals of pure triglycine acetate (TGAc) and crystal violet dye-doped (0.03, 0.05 mol %) triglycine acetate were grown by slow evaporation method with the vision to improve the properties of pure TGAc crystal. The crystallinity and phase purity of the grown crystals were analysed by PXRD. Dielectric properties of the grown crystals were investigated by impedance spectroscopy. The dielectric measurements were carried out in the frequency range 50 Hz to 5 MHz at room temperature. The frequency dependence of real part of dielectric constant (ε'), dielectric loss (ε"), loss tangent (tan δ), real and imaginary part of impedance (Z' and Z"), electrical modulus (M' and M") and ac electrical conductivity (σac) have been investigated. The dielectric constant and dielectric loss for the grown samples, have been found to decrease with increasing frequency. The decrease in permittivity and dielectric loss with increase in applied field frequency is in accordance with Maxwell Wagner theory. The enhanced dielectric constant of the doped crystals confirms the suitability of the grown crystals for energy storage capacitor applications. [ABSTRACT FROM AUTHOR]

AgI films were prepared by thermal evaporation technique at film thickness (300) nm deposited at room temperature. Quantum tunnelling is the dominant mechanism for ac measurements. AC conductivity σa.c and then frequency exponent are independent temperature but frequency dependent at frequency range (100 Hz – 100 kHz) in the temperatures range (298- 513) K. There is agree between real and imaginary dielectric constant at maximum peak of imaginary dielectric constant at (ωmaxτ=1) at ln(ω) equal to (11.04) (i.e wavelength=10 kHz). From the results of Cole - Cole diagram, fine semicircle is appeared and minimum relaxation time is equal to (1.30*10-5 sec) at annealing temperature 423 K which reflects the behaviour of dielectric dispersion for electronic devices like memory effects. [ABSTRACT FROM AUTHOR]

The paper presents the simulation and comparison of capacitance voltage characteristics of circular MEMS actuators using SiO2 and TiO2 nanostructures as dielectric material. The two groups considered for the present study use a sample size of 150 each. SiO2 and TiO2 are used as dielectric materials for the circular MEMS actuator of thickness ranging between 50 and 200nm. The capacitance voltage characteristics below pull in voltage and post pull in voltage of both the actuators are obtained and tabulated. The CV characteristics graph is plotted and compared statistically. The TiO2 nanostructured dielectric layer based MEMS actuator provides mean for capacitance at below pull in state=1.30261E-10 F and capacitance at post pull in state=2.99155E-10 F, SiO2 based MEMS actuator provides mean for capacitance below pull in state=3.66040E-12 F and capacitance post pull in state=5.93854E-12 F with significance value of less than 0.05. The sample size for the two MEMS actuator structures have been calculated and a total of 300 samples collected. It is observed that TiO2 dielectric material based MEMS actuator has significantly greater capacitance than SiO2. [ABSTRACT FROM AUTHOR]

Optical sensors based on a plasmonic multilayer stack, such as metal-insulator-metal (MIM), have attracted considerable attention over the past decades owing to their high resolution and high performance compared to conventional surface plasmon resonance (CSPR) sensors for bulk sensing (BS) applications. In this paper we show that CSPR is better than MIM sensors for thin film sensing, i.e. when a dielectric sensing layer (SL) is deposited on the outermost metal layer of the structure. We demonstrate that the deposition of a thin film SL on the top of the outermost-layer of an optimized multilayer structure, i.e. MIM, strongly decreases the evanescent electric field and the field enhancement at metal-SL interface and decreases the sensor's sensitivity for MIM versus CSPR. By considering the theoretical and experimental results we demontrated that CSPR is more suitable than MIM for thin films sensing applications. [ABSTRACT FROM AUTHOR]

Chiral optical forces exhibit opposite signs for the two enantiomeric versions of a chiral molecule or particle. If large enough, these forces might be able to separate enantiomers all-optically, which would find numerous applications in different fields, from pharmacology to chemistry. Longitudinal chiral forces are especially promising for tackling the challenging scenario of separating particles of realistically small chiralities. In this work, we study the longitudinal chiral forces arising in dielectric integrated waveguides when the quasi-TE and quasi-TM modes are combined, for enabling the separation of absorbing and non-absorbing chiral particles. We show that chiral gradient forces dominate in the scenario of beating of non-degenerate TE and TM modes when considering non-absorbing particles. For absorbing particles, the superposition of degenerate TE and TM modes can lead to radiation pressure chiral forces that are kept along the whole waveguide length. We accompany the calculations of the forces with particle tracking simulations for one specific radius and chirality parameter and show that longitudinal forces can separate chiral nanoparticles suspended in water even for relatively low values of the particle chirality. [ABSTRACT FROM AUTHOR]

Frequency tripling mirrors offer a promising alternative to complicated cas- caded arrangements for third harmonic generation. By incorporating optimised dielectric layers, we have achieved a remarkable conversion efficiency of 3.5 %. We will give a deep insight into FTMs and discuss applications. © 2024 The Author(s) [ABSTRACT FROM AUTHOR]

We use neural networks to address the challenge of deriving dielectric coating designs from the desired optical properties. We show that our trained neural network can automatically design common laser mirror coatings types efficiently. [ABSTRACT FROM AUTHOR]

It was found that a conventional oscillatory circuit, widely used to produce vibrations at frequencies used in radio broadcasting, is not suitable for generating vibrations in the centimeter wave range. Some successes have been achieved with a triode generator with a positive grid and a resonant two-wire line instead of an oscillatory circuit. Work on obtaining vibrations in the range of millimeter waves by the method of excitation of iron filings suspended in oil was carried out by scientists, but the desired results were not achieved until attention was paid to the excitation of vibrations in volumetric resonators. [ABSTRACT FROM AUTHOR]

Treatments of plasma waves usually assume homogeneity, but the parallel gradients ubiquitous in plasmas can modify wave propagation and absorption. We derive a quasilocal inhomogeneous correction to the plasma dielectric for arbitrary distributions by expanding the phase correlation integral and develop a novel integration technique that allows our correction to be applied in many situations and has greater accuracy than other inhomogeneous dielectric formulas found in the literature. We apply this dielectric tensor to the lower-hybrid current drive problem and demonstrate that inhomogeneous wave damping does not affect the lower-hybrid wave's linear damping condition, and in the non-Maxwellian problem damping and propagation should remain unchanged except in the case of waves with very large phase velocities. [ABSTRACT FROM AUTHOR]

This contribution explores an alternate route to forming pinhole-based poly-Si/dielectric/c-Si passivating contacts. The method utilizes controlled dielectric breakdown or electroforming to produce nanoscale pinholes in a thick (non-tunnelling) dielectric which, when annealed, allows dopant atoms to pass from doped poly-Si through the pinholes and into the c-Si wafer, forming conductive pathways. We show that the pinholes lose passivation after electroforming but can be repassivated with a forming gas anneal. N-type contacts show contact resistivities of ∼20 mOhm-cm2, but p-type contacts are ∼100 mOhm-cm2. Devices show a distinct kink in the J-V curve indicative of a barrier to transport. The method can be expanded to optimized dielectric passivation stacks (not just thin, single layers) and can be formed in parallel over the faces of the wafer in selected areas (pinholes only under the grid lines). [ABSTRACT FROM AUTHOR]

The electric field of light at the center of a one-dimensional mirrored multilayer structure consisting of two consecutive dielectric media A and B in the unit cell, namely AB mirrored multilayer structure, is well-known to rise exponentially by increasing the repetition number of the unit cell, in which the refractive index of A is larger than that of B. What happens if we now consider more than two dielectric media in the unit cell? In this study, we show that the electric field enhancement for an odd number of dielectric media in the unit cell, e.g. ABC structure, oscillates between zero and a certain finite value when increasing the repetition number. Meanwhile, for an even number of dielectric media in the unit cell, e.g. ABCD structure, the electric field at the center of the multilayer structure can be enhanced significantly when increasing the repetition number by simply tweaking the refractive index ratios of the dielectric media in the unit cell. Furthermore, the even number of dielectric media in the unit cell may fine-tune the electric field enhancement with better precision to obtain the desired value for photonic applications. [ABSTRACT FROM AUTHOR]

Graphene based microstrip patch antenna using FR4 dielectric substrate and RT Duroid dielectric substrate were designed at frequency range (4GHz to 7GHz) in order to optimize gain and return loss. Materials: Graphene-based microstrip patch antennas with FR4 dielectric substrates (n=16) and those with RT Duroid dielectric substrates (n=16) were evaluated using the Ansoft HFSS simulation tool for return loss and gain. Graphene based microstrip patch antenna using RT Duroid dielectric substrate has significantly higher gain (4.68dB) and less return loss (-10.05 dB) (p<0.05) than graphene based microstrip patch antenna using FR4 dielectric substrate with less gain(1.45dB) and high return loss (-9.46 dB). Optimal frequency for maximum gain and less return loss of FR4 substrate and RT Duroid substrate based graphene microstrip patch antenna was 5.0 GHz and 5.6 GHz respectively. Within this limits of study graphene based microstrip patch antenna using RT Duroid dielectric substrate of frequency 5.6 GHz offer high gain and less return loss. [ABSTRACT FROM AUTHOR]

Ni1-xBixFe2O4 (x = 0, 0.05 and 0.1) were synthesised by a solid state reaction method. All samples shows single phase from XRD pattern. From dielectric analysis, Bi-doped NiFe2O4 samples showed large dielectric constant, reduce dielectric loss and frequency dependency dielectric. The values of ε′ (at 15 kHz) are 545 for 5% Bi, 16504 for 10%Bi substituted in NiFe2O4, and are higher than that of NFO which is 80. Loss spectra show a peak at a lower frequency for 10% Bi-doped sample which suggests the occurrence of relaxing dipoles. AC conductivity increases due to the Bi content increases except for 5% Bi at a higher frequency. Frequency variation of impedance (both real and imaginary part) and observe that both impedance values are reduce with reduce of frequency [ABSTRACT FROM AUTHOR]

When using the sintered solid reaction method, the significant dispersion of MO8+ lithium ferrite was substituted by the general formula O4: y=0.03 to 0.8 with 0.04 increments. All samples' dielectric properties were investigated throughout a frequency range of 45 Hz–108 Hz. In order to reach a dielectric constant of y=0.60, the connection must be increasing, which causes the dielectric constant to first rise to y=0.25, then fall to y=0.20, and then rise to y=0.30. As frequency changes, so does the dielectric constant. The dielectric constants range from 70 to 90 megahertz (MHz). One explanation is that Fe5+ is now Fe7+. Due to the fast jump rate, the dielectric loss is extremely minimal at high frequencies. [ABSTRACT FROM AUTHOR]

This study aims to present the influence of two weight concentrations of Silicone Dioxide (SiO2) nanoparticles on the dielectric properties of single component impregnating resin based on polyesterimide (PEI) (UP 343 from Elantas producent). In this study the SiO2 nanoparticles were dispersed into PEI (with 0.5 and 1.0 wt.%) to prepare nanocomposites. The capacitance method based on the three-electrode measurement method to measure the frequency dependence of the real and imaginary parts of complex permittivity within the frequency range of 1 mHz to 1 MHz at temperature range of all conventional rotating and stationary windings from (+20 °C to +120 °C) was used. The presence of SiO2 nanoparticles in matrix of UP343 caused an increase of the real permittivity at higher temperatures compared to the pure matrix due to higher mobility of polymer chains. At low temperatures the decrease of the real permittivity was caused by the presence of highly immobile polymer chains in the interfacial regions around nanoparticles. The presence of different weight concentration of nanoparticles in the PEI resin had impact on the segmental dynamics of the polymer chains and changed a charge distribution in the given system. The shift of local relaxation peaks to lower eigenfrequency in the spectra of imaginary permittivity of investigated nanocomposites was observed. [ABSTRACT FROM AUTHOR]

In a world of miniaturized electronics, there is a rapidly increasing need for reliable, efficient, and compact energy storage systems with low-loss dielectrics. To address this need, this work proposes the development of compact, micro-capacitive energy storage devices compatible with IC processing so that they can be integrated monolithically on-chip. There are two main approaches to the fabrication of integrated on-chip micro-supercapacitor energy storage devices: interdigitated electrode (IDE) devices and parallel plate electrode (PPE) devices. As part of the design of such systems, this study aims to investigate the behavior of current density-voltage (J-V) in homogeneous and heterogeneous IDE and PPE devices to determine whether the anomalies between the interfaces of dielectric materials in such structures affect their leakage current. The ultimate goal is to design a solid-state capacitor energy storage module with low-loss dielectrics, high energy densities, and improved areal capacitance density that can offer a high number of charge/discharge cycles for portable power electronics. An understanding of J-V characteristics is crucial in achieving this objective. Specifically, this paper will explore and investigate nanolaminate, solid-state PPE, and IDE capacitive energy storage "modules" fabricated using nanolithographic techniques. The dielectric layers in these structures are composed of alternating nanolaminate layers of thin higher-k Al 2 O 3 and lower-k SiO 2 . Recent findings have shown that capacitive energy storage devices made from a large number of these on-chip multilayer nanolaminate energy storage PPE (MNES-PPE) structures that utilize the interfacial anomalies of thin high-k/SiO 2 nanolaminates could have the potential to overcome many of the limitations of current compact energy storage technologies. Preliminary projections indicate that these high-density nanolaminate capacitors with laminate thicknesses around 5 nm could produce devices with high volumetric energy densities ( ∼ 290 J/cm 3 ) that are significantly higher than conventional supercapacitors ( ∼ 20 J/cm 3 ). [ABSTRACT FROM AUTHOR]

Holmium (Ho) substituted KBi0.95Ho0.05Fe2O5 polycrystalline having P2/c space group is synthesized using solid-state reaction route. The phase purity is characterized by x-ray diffraction measurement. The temperature-dependent dielectric permittivity (ε΄) and loss (tan δ) is analyzed over a wide temperature range (10 K to 300 K) in the presence of 1.3 T and 0 T magnetic field. The temperature-dependent dielectric permittivity and loss plots are shifting with the magnetic field. It indicates the presence of Magnetodielectric (MD) signature in KBi0.95Ho0.05Fe2O5 polycrystalline. Variation of magnetodielectric with magnetic field shows a butterfly-like MD loop, indicating MD coupling. The extracted maximum room temperature magnetodielectric coupling is found to be 0.2% in KBi0.95Ho0.05Fe2O5 sample. The magnetic field-dependent impedance measurement is carried out to address the extrinsic effects behind the MD coupling. These results made it a prominent candidate for multifunctional device applications and provided space to investigate further the microscopic origin behind it. [ABSTRACT FROM AUTHOR]

The present study deals with the buckling phenomenon modeling in a dome-shaped dielectric elastomeric (DE) actuator used in different aerodynamic and fluid power system applications. The DE actuator is a circular membrane type of actuator, which shows a large out-of-plane axial-symmetric deformation with an electrically induced loading condition. A classical continuum mechanics-based analytical model is developed to predict the electrically induced buckling deformation in the actuator. A detailed parametric study has been performed to see the influence of standard Neo-Hookean and Mooney-Rivlin types of potential energies on the geometrical and physical parameters. The findings show that the present model successfully links the sensitivity of different potential energies concerning the actuator's initial dome height and radius. [ABSTRACT FROM AUTHOR]

Chicken feathers are considered the waste products of the poultry industry and poor disposal management couldlead to solid waste generation and environmental pollutions. Alternatively, feathers can be processed into a low-grade animal feed, but this demands water and energy. Due to environmental and sustainability concerns, this waste should be effectively managed beneficiated. This study aimed to fabricate a low dielectric composite made from methacrylated epoxidized palm oil and chicken feather for semiconductor application. Composite samples were prepared with 0 wt%, 5 wt%, 10 wt% and 15 wt% of mass feathers. Flexural and mechanical properties of the composites were investigated. Composites samples were analyzed by scanning electron microscope, and differential scanning calorimeter techniques. Results revealed that the addition of CFs significantly increase the flexural strength. SEM study revealed that the surface of CF-MEPO composite was rough and unevenly distributed. The DSC analysis demonstrated that the glass transition temperature of CF-MEPO composite increase with increasing CF content. The dielectric constant of CF-MEPO composite was decreasing with increasing of frequency, ranges from 3.56 to 4.15 at 1 MHz, making it suitable for semiconductor application. [ABSTRACT FROM AUTHOR]

The performance of dielectric barrier discharge (DBD) treatment was investigated to demonstrate the potential use for palm oil mill effluent (POME) treatment in terms of biogas production and chemical oxygen demand (COD) and total solids (TS) reduction. The treatment was undergone by applying the different input voltage of 15, 20 and 25 kV for 3 hours of reaction time with a frequency of 50 Hz in a DBD glass reactor. The experiment was carried out at room temperature and under normal air pressure. The results showed that the biogas concentration increased with the increase of input voltage. The concentration of hydrogen, methane, carbon monoxide and carbon dioxide increased from the initial values by 85%, 10%, 33% and 99%, respectively, for the input voltage of 15 kV. Biogas concentration also increased with the prolonged reaction time, indicated that more energy was supplied to convert the organic pollutants to form biogas. The high reduction of pollutants in POME was achieved to 48% for COD and 42% for TS when the input voltage increased to 25 kV. The low reduction of COD and TS was probably caused by the high pH value of POME used in this study, resulting a poor degradation and agglomeration of COD and TS. [ABSTRACT FROM AUTHOR]

The article describes the sensors based on longitudinally nonplanar microstrip microwave structures for the dielectric parameters monitoring of materials and substances. It is shown that such sensors have a higher sensitivity and relatively small linear dimensions in comparison with sensors based on planar microwave structures. The computer modeling section presents the results of numerical electromagnetic calculations of the proposed structures. The numerical results of the applicability analysis of the sensors for liquids and solid dielectric objects are presented. In the experimental implementation section the process of dielectric substrate manufacturing using 3D printing technique is described. Comparative results are shown for computer electromagnetic modeling and experimental study of longitudinally non-planar structures. The measurement of the solid material dielectric parameters is presented in the experimental section. In conclusion the possible fields of the considered sensitive elements applications are discussed. [ABSTRACT FROM AUTHOR]

The silicon carbide (SiC)/ tantalum carbide (TaC) nanostructures doped polycarbonate (PC) films were synthesized to employ in various dielectric nanodevices. The dielectric parameters of PC/SiC/TaC nanostructures were determined to use in the dielectric fields. Results of dielectric characteristics for PC/SiC/TaC nanostructures showed the dielectric parameters of PC were enhanced with rising of the SiC-TaC NPs ratio. The dielectric constant and loss were reduced whereas the conductivity was rise as the frequency rises. Finally, the dielectric characteristics results indicated to the PC/SiC/TaC nanostructures may be use in various dielectric fields. [ABSTRACT FROM AUTHOR]

The dielectric characteristics of PMMA/SiO2−CeO2 nanostructures films were examined to utilize in various electrical and electronic nanodevices. The films of PMMA/SiO2−CeO2 nanostructures prepared by casting method. The dielectric parameters of PMMA/SiO2-CeO2 nanostructures were calculated. Results demonstrated the dielectric parameters of PMMA were rise with rise in the SiO2−CeO2 NPs content. The behaviors of ε' and ε" were reduced whereas the σAC rises with rise in the (f). The final results showed the PMMA/SiO2−CeO2 nanostructures may be utilized in various electrical and electronic nanodevices. [ABSTRACT FROM AUTHOR]

The results of the analysis of literature on polymer films for high-voltage pulse capacitors are presented. To design a capacitor with high specific characteristics and to expand capacitor nomenclature, new materials with predetermined properties based on modern technologies must be created. [ABSTRACT FROM AUTHOR]

In the present work, it has been presented a theoretical study to explore the effect of the polarization charge on the number of trapped ions within the aspect of the phenomenon of an ion mirror effect. A mathematical equation was derived, representing the surface potential by the effect of the polarization charge. The surface potential equation was modified to include the effect of the polarization charge by two ways, the first way is adopting a point charge distribution model and the second way is adopting a hemispheroid distribution model. The results showed that the polarization charge has a significant effect on the number of trapped charges. This effect appeared as a changing in the amount of surface potential as well as in the amount of the reflection point of the incoming ions. [ABSTRACT FROM AUTHOR]