depended on conductivity variation inside the material [1, 45, 46]. Furthermore, according to equations 3.5 and 3.6, space charge can be accumulated in insulation material in steady state condition due to the variation of permittivity to conductivity. As a result, by combining equation 3.2, 3.3 and 3.6, the equation of determining space charge in steady state condition can be written ∇.(ε_0 ε_r E)=∇.(ε_0 ε_r J/σ)=J.∇((ε_0 ε_r)/σ)+ (ε_0 ε_r)/σ ∇.J=J.∇ ((ε_0 ε_r)/σ)= ρ (3.7) or ρ=σE.∇( (ε_0 ε_r)/σ)…
The effective permittivity from equation 1, calculated from the experiment was Ɛeff =3.31, the class average was Ɛeff =3.31, and the literature value was Ɛeff =3.28. The class average is the same as my value due to the measurements calculated for the effective permittivity were close and did not have an number that was wrong and was due to error. The literature value shows that the value found in the lab has error in involved, but is accurate enough to be considered. The Loaded Quality (Q)…
1.1 Dielectric Materials Dielectric materials are insulating materials that exhibit the property of electrical polarization. Dielectric materials support charge by acquiring a polarisation in an electric field. 1.1.1 Electric susceptibility and permittivity When a capacitor with capacitance C0 is filled with a dielectric material, its charge storage capacity (capacitance) increases to a value of C. Than susceptibility (χ^') of the dielectric materials is given by χ^'= (C-C_0)/C Dielectric…
studied by SEM are shown in Fig. 5. The surface morphology of TCSt was characterized by its smooth, hexagonally well oriented, tubular, interconnected network structure. Meanwhile, the PANI/TCSt composite had rougher surface due to the deposition of PNAI aggregates on the surface of TCSt fiber. The PANI surfae morphology was characterized by its rough surface and larger holes [21, 22]. 3.9. Dielectric properties The permittivity (') of TCSt matrix was determined at four spot frequency points,…
The signal scattering by an object depends on various factors, including the environment, signal strength, and the material properties of the object .For a given signal source and the environment, the scattered signal depends on the electrical properties of the object, especially dielectric and conductivity. This principal is utilized to detect the tumor in the breast using microwave signals. Reflected signals also reflected from various part of the breast which is undesirable in microwave…
For a given hopping site, under dipole moment effect, the probability density, W(r), of having the nearest carrier trapped at a distance r is determined by the Poisson distribution as [72-75]: W(r)=4πr^2 N_t exp(-4/3 πr^3 N_t) (15) where r is the relative position of the dipole with respect to the charge. As a carrier trapped by a localized state, the potential energy of the Coulomb interaction between the carrier and dipole moment can be expressed as…
Typically it consists of two conductive plates with a dielectric material in between them. For parallel plate capacitors, capacitance can be expressed as, C = [ (Aεoεr)/d ]. Where Cis the capacitance, A is the overlapping area of the two plates, εois the permittivity of free space, εr is the relative permittivity of the dielectric material and d is distance between the plates. Capacitive sensors can be made very small, which allows the construction of dense sensor arrays. In general, capacitive…
geometrical shapes and dimensions but among all the shapes of microstrip patch, four of them are most common than another that are square, rectangular, dipole and circular. They are employed in wide range of modern applications because of their easiness to design and compatibility with printed-circuit technology. The basic form of microstrip patch antenna is consists a patch and a ground plane that are separated by dielectric substrate as shown in Figure 1.1. The surface of the bottom side of a…
LNMFO in the composites [22]. The ρx is measured by the general formula,〖 ρ〗_x=nM/(N_(A ) V), where n is the number of atoms in a unit cell, M is the molar mass of the sample, NA is Avogadro's number and V is the volume of the unit cell. The porosity of the samples was calculated using the relation, P(%)=(ρ_x-ρ_B)/ρ_x ×100. The dielectric and magnetic properties were carried out using WAYNE KERR 6500B Impedance Analyzer. To measure dielectric properties the samples were painted by conducting…
are usel as precursor solutions due to ease of low-cost, and ease of use of a wide range of water-soluble metal salt. It play very important role in the formation of thin film. In case of spray pyrolysis the velocity of the droplet is very important. The droplet characteristics and quality of film depends upon the density of the solution, viscosity and compressed air. When the air pressure is more droplet size decreases. On the other hand, if the air pressure is too small, the droplet…