Solid Dielectric Media Research Articles

Geometrical scale multiplier of the ring laser gyro with resonator containing a dielectric medium

An analysis of the literature shows that there are at least six qualitatively different analytical expressions for the geometric scale factor of a laser gyroscope with a flat- a mirror resonator containing a solid dielectric medium with a refractive index along the entire perimeter. According to one of these expressions, the parameter is inversely proportional to the value . In the article, is the expression for confirmed.

Analysis of HVDC superimposed harmonic voltage effects on partial discharge behavior in solid dielectric media

This paper presents an investigation of effects of high voltage direct current (HVDC) superimposed voltage harmonics on partial discharge (PD) behavior. Firstly, a single air filled void embedded in a slab of polymeric insulation was modeled using finite element methods (FEM). PD phenomena activated under the influence of rippled DC voltages were simulated using an interlinked environment of MATLAB and multiphysics simulation package COMSOL. Secondly, the results of the modeling were backed up by experimental tests, where HVDC superimposed harmonics were applied to artificial void samples in the lab and trends in the resultant PD characterized with varying harmonic orders and amplitudes. The results of both modeling and experiment are generally in agreement showing that as the harmonic orders and levels increase, the repetition rate of PD pulses rises in comparison to a purely DC applied voltage having the same peak amplitude. The findings of this study will assist in understanding of PD behavior under HVDC conditions where harmonic rippling occurs on the voltage waveform.

Estimation of the solitary-wave energy content in solid dielectric media with optical strong nonlinearity in the far-infrared range

The energy content of temporal solitary far-infrared waves propagating in solid dielectric media according to the optical lossless cubic–quintic Schrödinger equation is estimated analytically. In fact the above energy content, which is one of the two fundamental invariant quantities associated with the equation in question, is found to be an affine function of a key nonlinearity parameter.

Decomposition of dichloromethane and in situ alkali absorption of resulting halogenated products by a packed-bed non-thermal plasma reactor

For an effective decomposition and removal of organic halogenated compounds, a packed-bed non-thermal plasma reactor with in situ absorption of the resulting halogenated products by alkaline sorbent incorporated was proposed. In the plasma reactor, α-Al2O3 particles of 1 and 3 mm (mean particle diameter) were packed as solid dielectric medium to enhance the plasma power density in the reactor. Further, alkaline sorbent of Ca(OH)2 was doped onto the surface of α-Al2O3 particles, in order to remove halogenated products by in situ absorption with Ca(OH)2. A high-voltage and high-frequency pulsed power of −15 to 15 kV and 1 kHz was applied to the wire electrode of the plasma reactor by means of a DC power source. In the present study, as the sample of an organic halogenated compound that is most popularly used, we selected dichloromethane (CH2Cl2), and 500 ppm of the initial concentration of CH2Cl2 was fed into the reactor accompanied by air at a fixed flow rate of 500 × 10−6 m3 min−1 at room temperature. As a result, it was recognized that the amount of CH2Cl2 decomposed by non-thermal plasma in an α-Al2O3 particle bed increased with an increase in plasma input power. The ratio of decomposition of CH2Cl2 was almost 100% at 13 kV of electric power and 1 kHz frequency, and CO2, CH3Cl, COCl2, HCl, and Cl2 were observed as the major reaction products. On the other hand, when CH2Cl2 was introduced into the plasma reactor where α-Al2O3 particles doped with Ca(OH)2 were packed, the ratio of decomposition of CH2Cl2 became higher, compared to the case that α-Al2O3 particles were not doped with Ca(OH)2. Moreover, there were no halogenated by-product gases detected in the outlet gas from the reactor. As the solid reaction products, CaClOH and Ca(ClO)2·4H2O were detected on Ca(OH)2 by X-ray diffraction. From these findings, it was recognized that CH2Cl2 was decomposed more effectively without producing unwanted harmful halogenated by-products in the proposed non-thermal plasma reactor where α-Al2O3 particles doped with Ca(OH)2 sorbent were packed.

TEM HORN ANTENNA FOR ULTRA-WIDE BAND MICROWAVE BREAST IMAGING

A novel TEM horn antenna placed in a solid dielectric medium is proposed for microwave imaging of the breast. The major design requirement is that the antenna couples the microwave energy into the tissue without being immersed itself in a coupling medium. The antenna achieves this requirement by: 1) directing all radiated power through its front aperture, and 2) blocking external electromagnetic interference by a carefully designed enclosure consisting of copper sheets and power absorbing sheets. In the whole ultra-wide band the antenna features: 1) good impedance match, 2) uniform field distribution at the antenna aperture, and 3) good coupling efficiency.

Towards Teraton EeV Neutrino Telescopes

The highest energy cosmic rays provide compelling evidence for EeV neutrino sources, if we can achieve the Teraton target volumes needed. At 10 TeV energies and above neutrino astronomy is in fact the only astronomy with a clear view of the whole universe. Radio detection of neutrino cascade interactions in ice and other solid dielectric media, via the Askaryan effect, provide a realistic path toward this goal.

Radioactive Charging Effects with a Dielectric Medium

A process is described in which radioactive radiation traverses a solid dielectric medium to charge a collector electrode. This process offers a simple method of studying effects of radiation on matter such as bombardment-induced conductivity, secondary emission, charge soakage, and radiation absorption. Typical data are given. Possible application of this process for the construction of a current or voltage source for use in electronic devices is discussed.