In this article, a systematic numerical study is described of the effect of the polydispersity of suspensions of spherical particles on their dielectric behavior, in both the frequency and time domains, starting from the model proposed by DeLacey and White (J. Chem. Soc., Faraday Trans. 2 77, 2007 (1981)) for monodisperse suspensions. The distribution function of relaxation times, characterizin...

to date, a number of numerical methods, including the popular finite-difference time domain (fdtd) technique, have been proposed to simulate ground-penetrating radar (gpr) responses. despite having a number of advantages, the finite-difference method also has pitfalls such as being very time consuming in simulating the most common case of media with high dielectric permittivity, causing the for...

Infectious diseases are one of the leading causes morbidity and mortality worldwide, antibacterial resistance exacerbates situation. So this study aimed to investigate genes responsible for folate inhibitor pathway antagonists outer membrane protein among gentamicin-resistant K.pneumoniae isolates. The results showed that out 481 specimens, 270 (56.13%) bacterial growth versus 211 (43.87%) no g...

When a sinusoidal ~ac! field is applied to a suspension containing nonlinear dielectric particles, the electrical response will generally consist of ac fields at frequencies of the higher-order harmonics. The situation is further complicated by an intrinsic dielectric dispersion, which often occurs due to the surface conductivity or inhomogeneous structure of the particles. We develop a perturb...

Dielectric spectroscopy was applied to porous nanocrystalline Na0.5K0.5NbO3 (NKN) ceramic green body, wherein influences of percolation effect and water adsorption at pore surface of the ceramic green body on dielectric response were examined over wide temperature (150 to 450 K) and frequency (100 Hz to 1 MHz) ranges. Dielectric permittivity of the ceramic green body is about 2–3 orders of magn...

Mixed ferroelectrics exhibit unusual precursor effects. In KTa12xNbxO3, polar nanoregions have been shown to condense approximately 20 K above the transition for all Nb concentrations, 1.2%,x,50%, as a result of medium-range collective interactions between Nb off-center ions. These interactions are also responsible for the observation of hysteresis loops in the polarization and dielectric nonli...

power transformers are key components in electrical power supplies and their failure could cause severe consequences on continuity of service and also generates substantial costs. identifying problems at an early stage, before catastrophic failure occurs, is a great benefit for reliable operation of power transformers. frequency response analysis (fra) is a new, well-known and powerful diagnost...

We study the solvent-induced frequency shifts of the OH-stretching mode of 1-naphthol and 2-naphthol in nonpolar/weakly polar solvents, subject to electronic excitation, with ultrafast UV/mid-infrared pump-probe spectroscopy and theoretical modeling based on Pullin's perturbative treatment of vibrational solvatochromic effects. The model is parametrized at the density functional theory (DFT) le...

Photonic bandgap (PBG) structures constructed from lossy, dispersive dielectric and metallic materials are characterized in terms of their reflection and transmission properties. Particular emphasis is given to PBG structures with defects. These PBG structures are modeled analytically with an ABCD matrix method for their single-frequency response. They also are modeled numerically with a finite...

This article reports a study on the dielectric relaxation processes of Cd2Nb2O7 compound. Three dielectric relaxation modes I, II, and III were reexamined. By using the Cole–Cole equation fitting of the frequency dependence of dielectric constant and loss, we obtained more precise relaxation time data, compared to the data reported in the literature. The results indicate that the relaxation tim...