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In this work, the La0.8Sr0.2Fe1-xMgxO3 (x = 0.1, 0.2, and 0.3) perovskite materials were effectively prepared using the sol-gel method through the sintering process to form bulk material. XRD analysis revealed that these perovskite materials are well suited to the Pbnm space group and have an orthorhombic structure. With increasing Mg substitution, the lattice parameters and crystallite size increase, indicating that the presence of Mg2+ in the crystal lattice inhibits the growth of the crystallite size. By Impedance Spectroscopy method using RLC meter, at room temperature, the electrical properties of the material were determined as a frequency's function (100Hz-7MHz). The conductivity of La0.8Sr0.2Fe1-xMgxO3 was contributed by the grains and grain boundaries, according to the Nyquist and Bode plots. Because of the hole carrier, the Nyquist plot of complex impedance increases when Mg is substituted. Real part impedance analysis explains the existence of space charge polarization at low frequency. The semicircle's diameter increases from increasing to doping with magnesium. This means that doping with magnesium will cause the resistance of the material to increase. The impedance data shows that as the Mg content increases, the impedance value decreases. According to dielectric research, dielectric spectroscopy shows that as Mg doping increases, the dielectric loss increases and the dielectric constant (ε′) of samples decreases at a lower frequency. [ABSTRACT FROM AUTHOR]

Dielectric properties are crucial for designing efficient materials and devices across a range of technological applications. In this study, a topological insulator pallet of Bi2Te2.9Se0.1 has been prepared using Palletizer. Compressed Pellet into a circular (Bulk) shape was used for the dielectric parameter study. The dielectric parameters were examined by a solid test fixer of VNA at room temperature. The dielectric properties have been found and got the peak in the XRD characteristic. Dielectric loss is almost constant and after that, it decreases which shows the polarization and charge of the material. XRD analysis was done for used to identify the crystal structure. [ABSTRACT FROM AUTHOR]

Ceramic materials based on the composition 0.98(Na0.5K0.5NbO3) + 0.02(Sr Bi0.5Nb0.5O3) + x ZnO (x=0.0, 0.45) have been synthesized through a solid-state reaction method and characterized to explore their unique properties and potential applications. In this study, we investigated the influence of varying " x wt% ZnO values on the physical, electrical, and structural characteristics of Na-K-Nb-O and Sr-Bi-Nb-O matrix (coded as NKBN) ceramics. Our findings show that the dielectric characteristics of the NKBN ceramics are significantly affected by the addition of ZnO to the ceramics. We noticed differences in the dielectric constant and dielectric loss depending on the ZnO doping. Additionally, the crystal structure and microstructure of the ceramics were revealed through structural analysis utilising methods including X-ray diffraction and scanning electron microscopy, which had an impact on their mechanical and thermal properties. With rising frequency and temperature, it was found that the dielectric characteristics decreased, which showed that the samples' conductivity had increased. The change in dielectric behavior were observed and confirmed from the dielectric study of the samples for electronic application. [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte (SPE) systems prepared with poly (ethylene oxide) PEO as polymer and Rubidium Bromide (RbBr) as salt. The SPE system PEO: RbBr doped with 10 wt% of RbBr, which is stable and exhibits the highest ionic conductivity of 4.02×10−6 Scm−1, is modified structurally by irradiating with a beam of oxygen ions. Ionic conductivity and dielectric properties of the SPEs were evaluated by studying complex impedance spectra. SPE irradiated with 1×1015 ions/cm2 shows one-order enhancement conductivity (3.61×10−5 Scm−1). The single peak in dielectric loss tangent curves indicates that segmental motion is responsible for ion motion in the polymer network. The decreased relaxation time (τ) in the irradiated SPEs shows increased segmental motion due to the reduced crystalline phase. X-ray diffraction graphs show an increment in width and reduction in intensity of characteristic peaks, and thermal studies show a decrease in glass transition temperature (Tg) and melting point (Tm) in the case of irradiated SPEs. These observations support the observed enhancement of the amorphous phase due to irradiation. The appearance of the D-LAM band in Raman spectra further proves the modification in the morphology of SPE systems. [ABSTRACT FROM AUTHOR]

The Magnetoelectric composites with thickness of 0.3mm of high piezoelectric voltage coefficient material, PbZr0.58Ti0.42O3 and magnetostrictive material, Cu0.6Co0.4Fe2O4 were fabricated by Screen printing method. XRD analysis indicates the presence of inverse cubic spinel structure in the ferrite phase and tetragonal perovskite structure in the ferroelectric phase. The computed lattice parameters and crystallite sizes for both ferrite and ferroelectric phases correspond well with values reported for comparable systems. Based on space charge polarization mechanism, the dielectric constant and loss tangent with frequency are explained for laminated films of Cu0.6Co0.4Fe2O4/PbZr0.58Ti0.42O3/Cu0.6Co0.4Fe2O4 and PbZr0.58Ti0.42O3/Cu0.6Co0.4Fe2O4/PbZr0.58Ti0.42O3. The magnetization hysteresis loop characteristics for both laminated thick films demonstrate that the loops are completely saturated and reveal the presence of an ordered magnetic structure. The DC resistivity graphs show that the resistivity of laminated film composites decreases with increasing temperature, demonstrating semiconductor behaviour in both layered composites. In a DC magnetic field range of 200Oe to 400Oe, the peak values of the ME coefficient in laminated thick film composites of Cu0.6Co0.4Fe2O4/PbZr0.58Ti0.42O3/Cu0.6Co0.4Fe2O4 and PbZr0.58Ti0.42O3/Cu0.6Co0.4Fe2O4/PbZr0.58Ti0.42O3 are 91 mV/Oecm and 83 mV/Oecm. [ABSTRACT FROM AUTHOR]

In the event of a power transformer failure, the utility could experience an interruption in its power supply. Many factors, including winding deformations, insulation deterioration, transient and overloaded conditions, etc., can lead to this kind of failure. This research explores the relationship between polarisation and depolarization current (PDC) measured from the oil impregnated paper insulation of a high voltage (HV) power transformer to reveal data about the state of the insulation used in these devices. Paper insulation in a power transformer has been documented to age in a non-uniform fashion. Popular models that can model non-uniform ageing include the conventional Debye model (CDM). In the current study, we employed CDM to foresee the performance of oil-impregnated paper insulation. Further, dielectric loss tan and overall insulation conditions have been explored, with the largest magnitude of Z evaluated from the transfer function (TF) of the CDM model impacting most to the insulation condition and projected moisture present in the insulation paper. [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]

By using the solution casting technique, a polymer electrolyte composed of a hexanoyl chitosan/PVC blend as the host polymer, sodium iodide (NaI) as the salt, and 1-methyl-3-propyl imidazolium iodide (MPImI) as the ionic liquid was prepared. In the temperature range of 303 to 343K, the effect of MPImI concentration on the dielectric characteristics of hexanoyl chitosan/PVC (90:10)-NaI complexes was investigated. According to the dielectric studies, both frequency and temperature had a significant impact on the samples' dielectric characteristics. In the lower frequency region, the dielectric constant, εr and the dielectric loss, εi are found to rise with temperature, while these effects are almost negligible in the higher frequency region. Based on electrode polarization, this behaviour can be described. It was found that the conductivity's frequency dependence obeyed the universal power law. The quantum mechanical tunnelling (QMT) model was used to explain the conduction process of the electrolyte system. [ABSTRACT FROM AUTHOR]

In the present work, nanocomposites of polyvinyl alcohol (PVA) and sodium iodide (NaI) nanoparticles have been prepared by casting technique. PVA has been doped by different percentage of sodium Iodide (0, 1, 2, 3 and 4 wt. %). The structural, electrical and optical properties of polymer electrolytes have been investigated. The experimental results showed that the D.C electrical conductivity increases with increase the sodium iodide nanoparticles concentrations. The activation energy of D.C electrical conductivity decreases with increase of sodium iodide nanoparticle concentrations. At low frequency, the variation of dielectric constant and dielectric loss with frequency shows the presence of material electrode inter-face polarization processes. The exponent factor found is between 0.98 and 0.086 and obeys the universal power law. The optical properties of samples are investigated in the wavelength range from 200 nm to 1100 nm at 300 K using UV-Vis spectroscopy. The absorbance, extinction coefficient, refractive index and reflectance of PVA doped with NaI increase with increasing of doping percentages except the transmittance. The real and imaginary parts of dielectric constants and optical conductivity are increasing with increase sodium iodine concentration. From direct allowed transition the optical energy gap decreases from 4.27 eV (for pure PVA) to 4.22 eV (for PVA+40%NaI). [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]

Polymer-based composites with high dielectric performance and superior discharge energy capability are highly desirable for advanced electrostatic capacitor applications. Herein, polymer-ceramic thick composite films with high dielectric permittivity were successfully fabricated by blending poly (vinylidene fluoride) (PVDF) polymer and barium titanate (BaTiO3/BT) particles (5 wt% and 10 wt% loading) using tape-casting. Structural and dielectric properties of the PVDF-BT nanocomposite films at room temperature have been investigated. X-ray diffraction studies indicate the evolution of the β-phase of PVDF in the nanocomposite films. Scanning electron micrographs show the homogenous dispersion of BT nanoparticles within the PVDF polymer matrix with small agglomeration in some confined areas. With the increasing weight fraction of BT, the dielectric permittivity increases while the tangent loss decreases. At 1 kHz, the dielectric permittivity and tangent loss values for nanocomposite with 10 wt% loading of BT nanoparticles are ∼21 and ∼0.05, respectively. Also, the value of the dielectric constant remained approximately constant in the frequency range of 1 kHz to 100 kHz. [ABSTRACT FROM AUTHOR]

In this particular piece of work, we have successfully synthesized a high-temperature lead-free Sb2O5 modified Bismuth Titanate (Bi4Ti3O12) polycrystalline solid solution using the conventional solid state route. The effect of Sb2O5 doping was investigated systematically for two different compositions (1.5 mol% and 3 mol%), and compared for their dielectric and ferroelectric properties with that of pure Bi4Ti3O12. The Sb2O5 added Bi4Ti3O12 compositions form non-stoichiometric oxygen-rich materials when introduced into the lattice and are expected to compensate for the oxygen deficiency of the pure compound, which is reflected in the significantly suppressed dielectric relaxations in the temperature-dependent dielectric permittivity responses. The room temperature ferroelectric study reveals an enhancement in remnant polarization in the Sb2O5 modified compositions. The 3 mol% Sb2O5 doped Bi4Ti3O12 showed promising characteristics for high temperature applications with increased dielectric constant (142 to 205 at 10kHz), decreased high temperature dielectric losses (1.33 to 0.02 at 10kHz at 300°C) and increased remnant polarization (2Pr = 0.6 to 7.75µC/cm2). [ABSTRACT FROM AUTHOR]

Ferrites are the most commonly known magnetic materials while multi-walled carbon nanotubes (MWCNTs) are known for superior conducting capability. Nanoparticles of ferrites integrated in MWCNTs exhibit excellent electromagnetic (EM) wave absorption efficiency. Main mechanism involved here is the matching between magnetic and dielectric loss. A thin layer of Ni-Zn-Co ferrite/MWCNT nanocomposite of thickness ∼ 1 mm can absorb ∼ 99.4 % (−22 dB) of the incident EM wave at a frequency of 15.24 GHz while Li-Zn-Co ferrite/MWCNT nanocomposites exhibits 99.1 % (−20.5 dB) absorption of incident EM wave at 15.27 GHz. These ferrite/MWCNT nanocomposites could be highly beneficial for shielding harmful EM waves at high frequencies. [ABSTRACT FROM AUTHOR]

In this research effect of incorporation of maghemite nanoparticles and graphite in chitosan membranes is studied using dielectric spectroscopy technique. Graphite was used as it has high electrical conductivity and is affordable. It is observed that the dielectric constant, dielectric loss, dissipation factor and conductivity are affected due to the presence of graphite and maghemite in the nanocomposite films. The films were made using solution casting technique. The conductivity increased when maghemite nanoparticles were included in the nanocomposites. This research could benefit battery technology and microelectronics. [ABSTRACT FROM AUTHOR]

Low dimensional magnetic ferrite nano particles play a crucial role in multiferroics due to the technological ME coupling based applications. In this present work low dimensional Co0.5Zn0.5-xCuxFe2O4 (x = 0.01, 0.02, 0.03, 0.04 and 0.05) (CZFO) ferrite nano particles were synthesized by modified auto combustion method with citric acid (C6H8O7) as the fuel and detailed investigation of the room temperature structural, magnetic and electrical properties. The X-ray diffraction pattern of all the samples confirms the formation of single phase with cubic structure Fd-3m space group. The Rietvield refinement technique was used to extract the atomic level structural information for all the samples and Scherer's equation used to estimate the crystallite size micro strain is around 8.65 nm and 0.6246 X 10−3. FTIR clearly shows the vibrational absorption band at 572 cm−1 is due to stretching of Fe-O and noticeably observed the effect of Cu on Fe-O bond. Room temperature M-H loops measurements were carried out to understand the ferrimagnetic behavior of all the samples. Cu doping to CZFO it reveals a high saturation magnetization (Ms), and remnant magnetization (Mr) at x = 0.05. The frequency depends of dielectric constant and dielectric loss carried out for all the samples and it implies that gradually decreasing with increasing of frequency and later it becomes linear. This is the Maxwell–Wagner type of polarization in accordance with Koop's theory. [ABSTRACT FROM AUTHOR]

Antennas are one of the many scientific and engineering fields that have been greatly impacted by the use of fractal geometry. Commercially available antennas for various telecommunications applications already use several of these shapes. It has been demonstrated that certain antenna features can be improved to varied degrees by using fractal geometries. The fractal shape and its characteristics are addressed in this paper. The suggested antennas are waveguide fed and have fractal structures that lower the resonance frequency of the antennas through the use of iterative methods. By merging several shapes, the bandwidth was maximized, resulting in a hybrid fractal antenna. CST Microwave Studio Suite software was used to analyze the fractal antenna. The constructed antenna features a nice Omni-directional pattern that is appropriate for RFID applications, is lightweight, low profile, and simple to build. The same FR-4 free losses substrate with a dielectric constant of r=4.3 and a thickness of 1.6 mm will be used to print the proposed antennas. The modified Sierpinski method was used to base the designed antenna on a zero-order square patch antenna while introducing various fractal geometries to reduce the size of the antenna. The output of the dual-band antenna with directivity of 4.6 and 5.37 alternating between 3.8 and 4.65 GHz that was proposed. [ABSTRACT FROM AUTHOR]

This paper focusses on impedance analysis of the different phases of oxides of manganese, prepared by solution combustion method using mixture of urea and glucose as fuels. The frequency dependence of real part of dielectric constant (ε'), dielectric loss (ε"), loss tangent (tan δ), electrical modulus (M' and M") and ac electrical conductivity (ζac) have been investigated by impedance spectroscopy analysis. While the values of dielectric constant, dielectric loss, loss tangent and ζac decrease, the values of elastic modulus increase for the prepared samples when frequency was increased. It has been observed that, Mn3O4 (hausmannite) crystals exhibits higher dielectric constant in comparison with Mn2O3 (bixbyite). The decrease in permittivity and dielectric loss with increase in applied frequency is in accordance with Maxwell Wagner theory [ABSTRACT FROM AUTHOR]

Polypyrrole and Polypyrrole/Tin Oxide nanocomposites were synthesized by insitu polymerization via the chemical oxidative method using ammonium persulphate as oxidizer. PPy/SnO2 nanocomposites were synthesized with weight percentages 9% and 18% of SnO2. The synthesized PPy and PPy /SnO2 nanocomposites were characterized by employing different characterization techniques such as the X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM). The XRD, FTIR and SEM confirm the successful insitu polymerization of pyrrole monomer during the preparation of PPy and PPy /SnO2 nanocomposites. Dielectric and ac conductivity studies on the SnO2, PPy and PPy/SnO2 nanocomposites have been carried out using impedance analyzer model HIOKI 3532-50 LCR HiTESTER Version 2.3. The frequency dependence of ac conductivity, dielectric constant and dielectric loss of the synthesized SnO2, PPy and PPy/SnO2 nanocomposites were investigated and reported in this paper. [ABSTRACT FROM AUTHOR]

In this work, the nanocomposites consisting of polyvinyl alcohol and polyvinyl pyrrolidone as a matrix and yttrium oxide as a filler, which were investigated with different percentage of yttrium oxide (Y2O3) (0, 3, 6, 9, and 12) wt. %. The dielectric property was measuring in a range (100 Hz – 5 MHz) frequency at room temperature, that it decreases with increasing a frequency while increases with increasing the content yttrium oxide. Dielectric loss decreases with increasing the frequency and increase with increases yttrium oxide content. The electrical conductivity (A.C) of nanocomposites increases when the frequency of electrical field applied and content of yttrium oxide (Y2O3) increases. [ABSTRACT FROM AUTHOR]

An important group of polymers with a wide range of applications is polyurethanes (PUR). In this contribution two-component system (2K PUR) is used to describe the effect of filler ZnO (Zinc Oxide) on the dielectric properties of industrial polyurethane marked as VUKOL N22 (from VUKI a.s.). From the results of the investigations carried out, it is evident that the incorporation of ZnO a decrease of real permittivity was observed due to a lower mobility of polymer chains connected to nanoparticles. Lower dielectric losses are associated with the lower relative permittivity. The SEM pictures show the distribution nanoparticles in matrix. Temperature-related relaxation peaks were observed in dissipation factor frequency spectra. Scanning Electron Microscopy (SEM) was used to measure the size and distribution of dispersed particles, and Energy Dispersive X-ray (EDX) analysis was used to confirm the chemical nature of particles. [ABSTRACT FROM AUTHOR]

Many papers have recently been published on the dielectric characterisation of polymer composites utilized as dielectric materials for energy storage. Higher particle material dielectric constant ԑ' and dielectric loss ԑ" have found widespread application in high-speed communication networks. The frequency dependence of the insulating constant ԑ' and dielectric loss ԑ" in pure polyester resin and polymer/nano-halloysite composites with varied weight fractions is investigated up to 5MHz. The fact that the value of decreases with increased frequency implies that orientation polarization is the predominant contributor to polarization. The electrical characteristics of nanocomposites that are sensitive to the uniformity of nano-halloysite dispersal in the polyester matrix and the dispersion between nano-halloysite and polyester matrix are examined in detail. [ABSTRACT FROM AUTHOR]

Single crystals of (ADP) were grown from salt water by slow evaporation solution growth technique at room temperature. Optically transparent single crystals with dimensions up to 1.3×0.7×0.3 cm3were harvested. The crystalline nature of the grown crystal was confirmed using powder X-ray diffraction. The FTIR studies are performed to identify the presence of various functional groups in the grown crystals. The mechanical properties are studied by Vicker's micro hardness test. Dielectric properties such as dielectric constant and dielectric loss were studied as a function of temperature and frequencies. The low dielectric loss at higher frequency implies that grown crystal has good optical quality and lesser defects. [ABSTRACT FROM AUTHOR]

By using slow evaporation method, L-L-histidine Perchlorate (LHPCl) and magnesium doped L-L-histidine Perchlorate, a semi organic nonlinear optical (NLO) substance, was developed. Both pure and doped crystals belong to the monoclinic structure with the P21 space group, according to the powder XRD analysis. The FT-IR analysis was performed using a BRUKER IFS 66V spectrometer. It confirms that the crystals have a variety of functional groups. The UV-Vis-NIR spectra of pure and doped LHPCl reveal a low cutoff wavelength of 243 nm, which is appropriate for SHG laser radiation of 1064 nm. Kurtz powder technique verified the SHG property. The Vickers microhardness measurement verifies the material's hardness. The dielectric studies indicate that both dielectric constant and dielectric loss decreases with increase of temperature in all frequencies. Both pure and doped LHPCl demonstrate positive photoconductivity, according to photoconductivity reports. [ABSTRACT FROM AUTHOR]

This article presents four port MIMO system for LTE operation. The presented MIMO consists of single patch which is excited with coaxial feeding. The presented MIMO is implemented on substrate (Nylon) having dielectric constant (εr) of 2.65 and dielectric loss (tan δ) 0.03. 100 X 100 X 1 mm3 are the dimensions of the antenna. It provides 34.4% of bandwidth at 2.5 GHz (2.15 GHz to 3.01 GHz) for |S11|≤-10 dB. The projected model can consist of 4G band 52 (3300-3400 MHz), band 41 (2496 – 2690 MHz), band 40 (2300-2400 MHz), band 38 (2570-2620 MHz), band 34 (2010-2025 MHz) and band 30 (2305-2315 MHz) at 2.5 GHz resonating frequency with operating band width of 860 MHz. Low mutual coupling and acceptable gain is achieved in projected MIMO. Under the operating band it provides>21dB isolation among the ports.ANSYS Electromagnetic suite is used for simulation. [ABSTRACT FROM AUTHOR]

For LTE operation a two port MIMO antenna is presented in this paper. It consists of single patch which is excited with coaxial feeding. The system is intended using Nylon substrate, the dielectric constant of the substrate is 2.65 and dielectric loss (tan δ) 0.03. Dimensions of the proposed MIMO are 100 X 100 X 2 mm3. The antenna provides a band to covers 3.13GHz to 3.45 GHz for |S11|≤-10 dB. This model can refuge LTE/4G band 22 (3410-3500 MHz), band 42 (3400-3600) and band 52 (3300-3400) at 3.38 GHz resonating frequency with operating band width of 320 MHz. The presented MIMO is found to achieve low mutual coupling and acceptable gain. This antenna system provides>47dB isolation among the ports under the operating band. Hence, this system is most appropriate for 4G as well as WiMAX (3.4 – 3.6 GHz) applications. For simulation, ANSYS Electromagnetic suite is used. [ABSTRACT FROM AUTHOR]

Present day data processing electronics equipment has constraints with speed, bandwidth, power, and efficiency for communication. Fabrication of the several circuits on a single chip with advanced technology is the promising solution for wideband microwave application. Substrate Integrated waveguide is the method used for sensible approach with low power, much low copper loss and low dielectric losses. In this article we have presented an effective Band Pass Filter Using Slotted Substrate Integrated Waveguide (SSIW) Technique for the Applications of Ku/K Bands. The following advanced SIW based waveguide manages excessive powers and provides the large bandwidth. The proposed filter is designed by slotted type as H slot in met material septum of SSIW respectively. Implemented H-slot shaped filter accomplished amplification in bandwidth with operating frequency over the range of Ku/K band (16.5 GHz–19.9 GHz). Slotted SIW primarily microwave elements work on the cutoff frequencies pertained to the SSIW formatted structures, introducing in truncated components. We can know that SSIW based slotted elements offer a new achievable applications involving not only high level of miniaturized components but also integrated systems. [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]

The polymeric film of Y2O3 (1%) doped Poly-vinyl-Alcohol (PVA) were synthesized and were confirmed with X-ray diffraction technique. The microwave response of this sample was studied using a Vector Network Analyzer (VNA). Analysis of the various parameters such as dielectric constant, reflection coefficient, transmission coefficient, dielectric loss, and Quality factor, of the material wereundertaken. The response of the materials wasstudied in a range of frequencies varying from 9 GHz. To 11.5 GHz. These parameters show potential applications of the material for variousmicrowave applications in the X-Band. [ABSTRACT FROM AUTHOR]

(1-x)Bi5Ti3FeO15−(x)La0.67Sr0.33MnO3 for x = 0.2 multiferroic composite is synthesized via sol-gel modified method. The Rietveld refinement of X-ray diffraction confirms the presence of both orthorhombic (BTFO) and rhombohedral (LSMO) crystal phase with space group A21am and R-3c respectively. Scanning electron microscope (SEM) along with the EDX spectrum reveals the existence of LSMO small grains in a BTFO matrix of the composite. The preliminary signature of the MD effect in the composite is investigated from the temperature dependence of dielectric constant and loss plot at a fixed applied magnetic field (0T and 1.3 T). The maximum magnitude of MD and ML response is observed to be ∼0.31% and ∼0.03% at 300 k. This arises due to the possible coexistence of both capacitive and magnetostrictive effects. [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 implementation of the utilization of pico-hydro energy generators with circulation systems using water as the working fluid currently exists, but needs to be further developed so that it is more widely applied by the community. In the current situation, where we know that countries in the world are trying to have an environmentally friendly energy source. This research that has been completed aims to analyze how the implementation of the performance of using pico hydro if it is applied with a low head. In this study, the method was carried out experimentally on a laboratory experimental scale, this was done in order to obtain data to be able to proceed with the implementation of pico hydro at low head flow. In this section of the results we can present that with a low head the implementation of pico hydro can be applied, various blade angles provide information on an increase in performance if the angle is greater it can be seen that from point 0 to 90 there is an increasing tangential force that works, this is due to the increasing the magnitude of the applied force. As for losses, the greater the flow capacity, the greater the losses. The biggest losses are at the angle of the turbine shaft slope of 60° and blade 90, which is 0.28 m. [ABSTRACT FROM AUTHOR]

This revision aims is to examine the electrical possessions of AC composite materials Polyvinyl alcohol-Polyacrylamide-Silver (PVA-PAAm-Ag) and Polyvinyl alcohol-Polyacrylamide-Polymethyl methacrylate-Silver (PVA-PAAm-PMMA-Ag) at different frequencies between 100 Hz – 6 MHz and the Ag additives. PVA-PAAm-Ag and PVA-PAAm-PMMA-Ag were prepared using the solution casting method. The film thickness was measured using an electrical micrometer to be 80 µm. The LC meter is used for the AC electrical properties. The results show that the dielectric constant (ɛ) and dielectric loss (δ) decrease with the increasing frequency, and δ increased with the increasing content of Ag. Electrical conductivity (σ) augmented with the rising frequency and Ag content in PVA-PAAM-Ag and PVA-PAAM-PMMA-Ag composite. [ABSTRACT FROM AUTHOR]

Cobalt ferrite Co1.2Fe1.8O4 nanoparticles were synthesized using the sol-gel auto combustion process. The impact of calcination temperature on structural, Magnetic and electrical properties has been investigated. The cubic spinel phase formation of ferrite structure was confirmed using Fourier Transform-Infrared Spectroscopy (FT-IR) and X-ray Diffraction Patterns (XRD). The size of the formed crystallite of ferrite samples ranges from 26.909 to 39.712 nm and was discovered to be dependent on the calcination temperature. According to the images obtained with a Field Emission-Scanning Electron Microscopy (FE-SEM), the particle size increases as the calcination temperature rises. The existence of Co, Fe, and O in all samples was also verified using Energy Dispersive Spectrum (EDS). Magnetic parameters for the as-burnt and calcined samples such as coercivity, saturation magnetization, and remanence field were investigated using a Vibrating Sample Magnetometer (VSM). All of the samples exhibited ferrimagnetic behavior. Saturation magnetization (Ms),remanance magnetization (Mr), and squareness ratio (Mr / Ms) increase as the calcination temperature increase. This behavior is linked to spin canting and disturbance in the surface spin. Using an LCR meter, dielectric loss factor (ε''), dielectric loss angle (tanδ), the dielectric constant (ε'), and σac conductivity of all samples were investigated at room temperature as a function of frequency. Based on Koop's theory, Maxwell-Wagner polarization process, and hopping of electrons, the differences have been described in dielectric properties at frequencies ranging from 50Hz to 2MHz. With increasing frequency, all-dielectric properties exhibited natural behavior. [ABSTRACT FROM AUTHOR]

The influence of nano filler content on the mechanical and dielectric properties of epoxy nanocompounds is investigated in this research. Epoxy is used as the matrix material. A different ratio of ZnO nanofiller was used (0.1,0.3,0.5,0 and 0.7 by weight), The test samples were prepared using an open die type, and tests were performed (three-point bending, stiffness, modulus of elasticity, and dielectric), and the mechanical and dielectric properties of the composite materials were determined and evaluated. With increasing the percentage of nanofiller material, the values of dielectric constant and loss factor decrease, while bending strength, flexural modulus, and stiffness increased, values It were before adding the nanofillers (1.05 MPa),(0.164 GPa),(79 N/mm2) respectively, and after the reinforcement, they increased than they were to become (6.15 MPa),(1.636 GPa),(81 N/mm2) respectively. [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]

CZTS (Cu2ZnSnS4) nanostructure was obtained via hydrothermal method. The effect of water (w) and 2-methoxyethanol (2-M) on the structural, surface morphological, electrical and optical properties for thin films prepared via spin-coating technique. The XRD results indicated that all samples made of polycrystalline have a preferred direction along the plane (112). Moreover, the image obtained in the FESEM showed that the thin film prepared using 2-methoxyethanol possesses a sphere-like nanoparticles. The estimated optical band gaps are 1.44 and 1.54 eV for the samples prepared with 2-methoxyethanol and water, A.C Conductivity, dielectric constant and dielectric loss of all films were estimated by (C-F) measurement and the results were discussed. We concluded that using 2-methoxyethanol leads to films with best properties than water as solvent. [ABSTRACT FROM AUTHOR]

In this paper, the optical, electrical dielectric and structural properties of transparent, light blue and dark blue coated glass are studied. It is noted that the absorption of clear glass is higher than that of light blue and dark blue coated glass, while the reflectivity of light blue and dark blue coated glass is higher than that of clear glass. As for the insulation properties, it is found that both the real and imaginary dielectric constant and the loss factor are also affected by the change of frequency and the type of coating. An X-ray fluorescence device was used to identify the elements inside the glass composition to identify the type of paint causing the light and dark blue colors. While the light blue coated glass contains colored pigment elements such as vanadium and polonium which give the light blue color in addition to the main elements of the glass, while the dark blue coated glass contains the basic elements and pigment elements such as titanium and chromium which give the dark blue color. [ABSTRACT FROM AUTHOR]

In the present study, the effect of Zr substitution on the dielectric and ferroelectric properties of BaTiO3 ceramic has been investigated. Ba(ZrxTi1-x)O3 (x = 0.10,0.15 and 0.20) powder samples prepared via solid state reaction method were double calcined and sintered at 1100°C. The crystallinity of the samples has been assessed by X-ray diffraction. The dielectric and ferroelectric properties were measured in wide range of frequency and temperatures. The samples with 15% Zr concentration have higher value of dielectric constant and lower dielectric loss factor (tanδ∼0.15) as compared to other samples. P-E loop analysis shows an increase in the remanant polarization and coercive electric field with increase in Zr concentration. [ABSTRACT FROM AUTHOR]

The insulating oil is the most critical element of the transformers. For better performance of the transformers, the dielectric properties (AC Breakdown voltage (AC BDV), DC BDV, dielectric losses, and insulation resistance) should be in a considerable range. In the present scenario, mineral oils are used as dielectric insulation oil in the transformers, which is very hazardous to the environment as well as has a limited resource. In the present work, the dielectric behavior of blended ester oils (Natural and Synthetic) and mineral oil at different temperature levels have been investigated by using a 100 kV motorized AC/DC breakdown voltage test set and loss tangent, permittivity, and resistivity test set. The results revealed that the blend of coconut oil and synthetic oil (M4) gives better dielectric properties, i.e., AC BDV increases by about 51%, and DC BDV increases by 61% as compared to mineral oil. Thus, it is established that blended ester oils can be an alternative to traditionally used mineral oil. [ABSTRACT FROM AUTHOR]

In this paper, the optical, thermal electrical, dielectric and structure properties of transparent glass and light green and dark green coated glass were studied. It is noted that the absorbency of transparent glass is higher than that of light green and dark green coated glass, while the reflectivity of light green and dark green coated glass is higher than transparent glass. As for the insulating properties, it was found that both the real and imaginary dielectric constant and the loss factor were also affected by the change of frequency and the type of coating. The X-ray fluorescence device was also used to identify the elements inside the composition of the glass in order to identify the type of paint that causes the light and dark green colors. While the light green coated glass contains colored pigment elements such as titanium and zirconium which give the light green color in addition to the main elements of the glass, while the dark green coated glass contains the basic elements and pigment elements such as chromium (Cr) and potassium (K) which give The color is dark green. [ABSTRACT FROM AUTHOR]

The effect of Ca-less content in CaCu3Ti4O12 (CCTO) properties were studied. The CCTO ceramic was prepared by using solid state method with stoichiometric formula Ca1-xCu3Ti4O12-3x. The Ca content were decreased with five different concentrations which are x=0.00, 0.01, 0.02, 0.03, 0.05 and 0.10 respectively. The XRD results show single phase formation for all sintered CCTO and a small phase of CuO appeared when Ca content decreased. Apart from that, SEM micrograph for the compacted pellets show approximately the same size for all samples unless sample CCTO5 shows large particles which contribute to the segregation of Cu element. The dielectric behavior of CCTO was observed in a frequency range of 1 Hz - 10 MHz. The optimum dielectric constant was obtained at CCT05 with the highest ε0 (5.5 × 103) and lowest dielectric loss (tan σ) with a value of 0.5. This could be related to the less Ca content in which contribute to the higher Ca and oxygen vacancies in CCTO electro-ceramic. [ABSTRACT FROM AUTHOR]

The conventional technique of CaCu3Ti4O12 synthesis involved a very high sintering temperature (>1000°C) and long soaking time (>5h). The high temperature and time-consuming process caused the conventional technique to be inefficient and costly. In this study, the microwave sintering approached was carried out using an enhanced process to solve this problem and the dielectric properties and other properties are investigated. In this study, an enhanced silicon carbide (SiC)-based susceptor was utilized to optimize the microwave radiation temperature towards the CCTO sample. The CCTO samples were prepared using a solid-state reaction route. The X-ray diffraction analysis shows that the phase formation of cubic CCTO formed after the calcination process. The calcination process of CCTO powder was conducted conventionally in a furnace at 900°C for 12 hours. The CCTO cylindrical pellets were then sintered using a commercial microwave at 2.45GHz and 800W power. The sintering process was tested in five different irradiation times: 1 hour, 2 hours, 3 hours, 4 hours, and 5 hours. The electrochemical impedance spectroscopy conducted at 2.5V and 3V with 1Hz to 10MHz of frequency shows the dielectric behaviour performance of the sample concerning sintering time. The result reveals that the dielectric constant was best produced for 5 hours of sintering time. However, the sample can melt beyond the duration because the high heat generated at the sample's interior deteriorated the sample shape. The dielectric loss is also reasonably low between the time. It is then proven that completing the microwave sintering process in 5 hours is sufficient to improve the dielectric properties of the CCTO. [ABSTRACT FROM AUTHOR]

In the present paper, by modifying two sublattice pseudospin lattice coupled-mode model (PLCM) containing third and fourth-order phonon anhannonic interaction terms by adding extra spin-lattice interaction, direct spin-spin interactions terms, and electric field term is considered for Rochelle salt (RS) crystal By using double time-temperature dependent Green's function method, Dyson equation theoretical expressions for ferroelectric soft mode frequency, dielectric constant and dielectric loss tangent have been derived for Rochelle salt By fitting various model values of physical parameters, thermal variations for ferroelectric mode frequency, dielectric constant and dielectric tangent loss have been obtained for Rochelle salt. For validation of t heoretical results have been compared with the experimental results. [ABSTRACT FROM AUTHOR]

Polynorbornenes are known as materials demonstrating low values of dielectric constant. Dielectric properties of substituted polynorbornenes with different structure of the main chain bearing F-containing substituents in the side chains are discussed. The incorporation of bulky fluoroorganic groups in polynorbornene structure was found to be an effective approach for obtaining dielectric materials with low s' values and moderate or low dielectric loss. The impact of fluoroorganic substituents on dielectric properties depends on free-volume characteristics of the polymers and fluorine content. The polymer bearing perfluorinated n-hexyl substituent displayed the lowest value of ε' been reported for polynorbornenes to date. [ABSTRACT FROM AUTHOR]

This paper presents the synthesis of three new copolymers based on various derivatives of styrene and α-methylstyrene by radical emulsion copolymerization in an inert argon atmosphere using potassium stearate as an emulsifier and ammonium persulfate as an initiator. Styrene and α-methylstyrene copolymer are used in the production of capacitors as a dielectric element. These new copolymers are superior to styrene and α-methylstyrene copolymers in terms of permeability, which makes them competitive materials in the aspect of further implementation in industry. [ABSTRACT FROM AUTHOR]

The objective of this research is to study the influence of the substitution of Zn on Fe-site to the dielectric properties of LaFeO3. A series of LaFe1-xZnxO3 perovskite materials (x = 0.03 and 0.05) were successfully synthesized by the sol-gel method and then sintered to form bulk samples. XRD, SEM, and EDAX characterized the structure and element composition. The RLC-Meter used to measure electrical properties as well as resistance, dielectric constant, and tan loss. All compounds were single-phase, with no impurity phase. X-ray diffraction analysis showed that all samples have orthorhombic crystal structure and Pbnm space group. The SEM results of the bulk samples showed that the morphology of the particles was uniformly distributed. The electrical properties of LaFe1-xZnxO3 (x = 0.03 and 0.05) in the frequency range of 0.1 kHz-1000 kHz at room temperature were determined by impedance spectroscopy. Zn-doped LaFeO3 leads to an increase in the semicircular diameter Nyquist plot, impedance value, dielectric loss, and material conductivity. These results prove that zinc doping enhances the electrical properties of the material. [ABSTRACT FROM AUTHOR]

The composites of the form 0.5ZFO + 0.4BFO + 0.1GFO (S1) and 0.75ZFO + 0.2BFO + 0.05GFO (S2) and synthesized by solid state route are reported in this study. These composites were subjected to structural, energy bandgap and dielectric studies. The XRD spectral analysis confirms that all the three phases are present in the samples under study. The BiFeO3 phase has acquired orthorhombic (Pnma) crystal structure, ZnFe2O4 has crystallized into cubic (Fd-3m) structure where GaFeO3 exhibited trigonal (R3c) structure. Diffuse reflectance spectral study conveys the sample to possess wide energy bandgap ≈2eV. The dielectric studies reveals the samples are extremely good dielectric materials with average dielectric constant, low loss value and relatively low decreasing rate with respect to applied field for both features. [ABSTRACT FROM AUTHOR]

We throw light on Ni0.95Zn0.05O Oxide synthesized by solid state reaction route. The sample was characterized by X-ray diffraction and Raman for structural studies. XRD data study conveys the sample has acquired trigonal structure (R -3 m). The lattice formation is re-verified by Raman data study though the display of fundamental modes of vibration. UV-Vis spectral analysis convey the sample has an optical bandgap of 1.6eV. The room temperature frequency dependent dielectric study reveals the sample to be good dielectric material. The sample exhibits relatively low loss value with a character of relaxation phenomenon. The tuned optical bandgap, single phase nature, high dielectric constant with low dielectric loss makes it suitable for opto-electronic device applications. [ABSTRACT FROM AUTHOR]

Thermal decomposition method was used to synthesis non-stoichiometric nickel oxide at different sintering temperatures upto 1100 °C. X-ray diffraction method along with ritvield refinement is used for structure cauterization of synthesized compounds. The dielectric constant and dielectric loss was found to have dependency on stoichiometry. These results were interpreted as the decomposition temperature increases, which heals the defects present in the non-stoichiometric nickel oxide and Loss peak shifts to the higher frequency which is due to long-range hopping of charge carriers. [ABSTRACT FROM AUTHOR]