Accurate measurement of moisture content is a prime requirement in hydrological, geophysical and biogeochemical research as well as for material characterization and process control. Within these areas, accurate measurements of the surface area and bound water content is becoming increasingly important for providing answers to many fundamental questions ranging from characterization of cotton f...

This paper presents an extension to the rectangular dielectric waveguide technique to obtain the permittivity of samples iteratively from the effective refractive index measurements by using the solution of the wave equation. The effective refractive index is presented for several samples in the 33 GHz to 50 GHz frequency range. The method is very fast and simple and provides an accuracy of bet...

Abstract This paper considers the generaI properties of a jacket consisting of two closely spaced, but curved, conducting plates separated by a medium of uniform isotropic permeability and nonuniform isotropic permittivity for propagating dispersionless TEM waves. A simple form of this is a body of revolution with generalized axial propagation (generalizti coax) which can be synthesized with a ...

CaCu3Ti4O12 possesses one of the largest values of the effective dielectric permittivity in a large frequency and temperature range ever reported for a ceramic material, and is thus a very promising material for various electronic and electromechanical applications. The origin of such high permittivity has been attributed to ‘electrical’ heterogeneities in the microstructure [1-3]. By Chemical ...

In this paper, the possibilities of finding out surface plasmons in negative-permittivity metamaterial scatterers, using surface integral equations, are discussed. Electrostatic resonances manifest themselves as very high values of the polarizability for a certain (negative) value of the permittivity. Another way to locate the position of the resonances is to calculate the eigenvalues of the so...

We show that there are shape-independent upper bounds to the extinction cross section per unit volume of dilute, randomly arranged nanoparticles, given only material permittivity. Underlying the limits are restrictive sum rules that constrain the distribution of quasistatic eigenvalues. Surprisingly, optimally designed spheroids, with only a single quasistatic degree of freedom, reach the upper...

Multilayer antennas—for example, stacked patches—often employ low permittivity substrates, such as foams. These foams, however, tend to be fragile, difficult to glue, and difficult to bend. In a previous contribution, the authors described how a Duroid substrate may be drilled in order to obtain a low permittivity synthetic dielectric. This paper shows, by means of both practical and numerical ...

In this paper, the inverse problem of calculating the permittivity coefficient in electrical capacitance tomography (ECT) is considered based on the minimization of a special functional that depends on two regularization parameters. The calculation of the permittivity is an ill-posed problem difficult to solve. Firstly the theoretical analysis developed in [6] is reviewed. Then the basic concep...