In this paper we extend the recently developed models that predict the magnetic field produced by thermoelectric currents around spherical and cylindrical inclusions to the case of elliptical cross-section cylindrical and spheroidal inclusions. The extra geometrical complications are handled by utilizing already available solutions of similar problems in hydrodynamics and electricity. It is shown that the results reduce to those of the previous models when the aspect ratios of the inclusions equal unities.

Binary tellurite glass systems of the forms TeO2(100−x)-xAn Om whereAn Om = La2O3 or V2O5 and x = 5 to 20 for La2O3 and 10 to50 for V2O5 were prepared. UV-spectra of these glasses were recorded in the range of200–700 nm at room temperature. The optical energy gaps E optical and $E_{\rmtail}$ have been calculated from the optical absorption edge. UV cut-off and IR cut-off havebeen measured. Calculations of the oxide ion average polarizability ( $\alpha_0^{2-}$ ) andoptical basicity (Λ) have been done.

New composite materials based on aluminosilicate materials were developed to be used in orthopaedic or maxillo-facial surgery. They are called geopolymers or polysialate-siloxo (PSS) and were studied alone or mixed with hydroxyapatite (HAP). The properties of these materials were investigated for potential use in biological or surgery applications. In this work, the chemistry involved in materials preparation was described. Samples were characterized by some physico-chemical methods like X-ray diffraction (XRD), infrared spectrometry (IR) and electron dispersion X-ray spectrometry (EDX). Results indicate that the mixing hydroxyapatite-geopolymer (PSS) leads to a neutral porous composite material with interesting physico-chemical properties. A preliminary evaluation of its cytotoxicity reveals an harmlessness towards fibroblasts. These properties allow to envisage this association as a potential biomaterial.

The (Ba0.67Sr0.33)TiO3 thin film for dielectric bolometer mode of uncooled infrared focal plane arrays prepared on Pt/Ti/SiO2/Si by radio-frequency magnetron sputtering has been investigated focusing on the dielectric properties. X-ray diffractometer shows the BST films to be well perovskite structure. These films exhibit good surface morphology. The dielectric properties of the BST thin films have been measured as a function of temperature using a HP4284A LCR meter. According to the dielectric constant-temperature curve, the Curie temperature of the BST thin film is about 30 °C, around room temperature. The maximum change in the dielectric constant is as large as 78/k, and more than 21% relative change in the dielectric constant has been obtained.

A large variety of initiation results in a ram accelerator have shown that a series of interactive parameters play a key role, such as the design of the facility, tube diameter, shape of both the projectile and sabot and the choice of the reactive propellant mixture. Two different ram accelerators were used at ISL for this study, namely a 30-mm and a 90-mm-caliber. In addition to the diameter effect, it was observed that the dimension of the sabot must be adapted not only to the caliber of the tube but also to both the launching device and vent section that are located before the ram accelerator tube. For instance, a sensitive mixture yielded a superdetonative mode in the larger tube diameter facility at ISL. Comparative experiments were conducted in these two caliber ram accelerators at ISL. Important transient effects were observed as the projectile enters the tube which could explain the discrepancies between the data derived from similar devices. The aim of the present paper is to provide a series of data that show the effect of the tube diameter on the initiation process of the propellant mixtures that are currently used in this facility. The design of the sabot is also discussed.

The excess leakage current due to the ion implantationisolation process used in the fabrication of double mesa Self PassivatedGaAlAs/GaInP/GaAs Heterojunction Bipolar Transistors (SP-HBT) has been investigated.This ion implantation process, used to limit the active emitter length results in a drasticreduction of the current gain. The ideality factor of the recombination current associatedwith the ion implantation has been found to be 1.8, close to the conventional value of 2.

The dc and 100 kHz low pressure discharges in acetylene-nitrogen mixture have been studied here. Optical emission spectroscopy was used for identification of active plasma components and to determine plasma temperature. Relative concentrations of H, CH and CN were investigated versus experimental conditions by optical actinometry techniques. Emission intensities of N2 and N $_2^+$ normalized to intensity of argon line were also monitored as a function of experimental parameters. The rotational temperatures from the N $_2^+$ B $^2\Sigma_{\rm u}^+$ -X $^2\Sigma_{\rm g}^+$ (0-0) and CN B2 Σ +-X2 Σ + (0-0) bands and vibrational temperatures from the CN(B2 Σ +-X2 Σ +) and N2 (C $^3\Pi_{\rm u}$ -B $^3\Pi_{\rm g}$ ) spectra weredetermined. Plasma processes and plasma equilibrium state were discussed.

The non-local kinetics of the electrons in a cylindrical, axially symmetric hollow cathode discharge is theoretically investigated. A new multi-term method for solving the inhomogeneous Boltzmann equation in cylindrical coordinates has been developed to adequately describe the pronounced anisotropy of the electron velocity distribution function expected in the cathode fall region. This method is based on a tensorial representation of the expansion of the electron velocity distribution function in spherical harmonics. The resultant hierarchy of component equations has been specified to cylindrical geometry with rotational symmetry and axial uniformity. A subset of component equations could be separated which determines the relevant distribution parts needed to analyze the radial behaviour of important electron properties in the hollow cathode. Using measured profiles of the electric field, this subset has numerically been solved for a helium plasma at a discharge current of some mA and a pressure of few torr. Based on this approach in addition to the radial variation of the energy distribution, that of important transport properties and collision rates is studied and the non-local particle and power balance of the electrons are analysed. Some theoretical results are compared with available experimental ones.