Force Analysis of Reciprocating Rotary Planetary Mechanism with Elliptical Gears

Russian Engineering Research - Reciprocating rotary motion of the impeller in a mixer is produced by a planetary mechanism with elliptical gears. The forces in the planetary mechanism are analyzed....     

Equivalent Surface Impedance of an Infinite Array of Slot Impedance Loads Based on a Cavity Having the Cross-Section in the Form of an Equilateral Triangle

Journal of Communications Technology and Electronics - The two-dimensional problem about the excitation of an infinite array of slot impedance loads by a plane wave is considered. The aim is the...     

On stabilization of the Fermi level in Ga-doped PbTe-based alloys

The influence of Ga doping and irradiation with high-energy electrons on the galvanomagnetic effects in n-Pb_1?xGe_xTe:Ga (0.04?x?0.06) was investigated. Transitions to the metal-type conduction were found to occur both with an increase in the impurity content and as a result of irradiation. It is concluded that the impurity level does not pin the Fermi level. It is demonstrated that gallium doping and electron irradiation are the most effective complementary methods for controlling the electrical properties of alloys.     

Co-gasification of a lignite/waste-tyre mixture in a moving bed

The thermal treatment of waste-tyre by co-gasification with lignite was investigated on a commercial scale during the Lurgi gasification process. The experiments proved that this material can be treated in a mixture with lignite in the process of oxygen–steam pressure co-gasification in a moving bed, because a waste-tyre admixture improves the net calorific value of the raw gas obtained by 3% in comparison with that from the gasification of lignite alone. Further, it was found that the H₂S and CH₃SH contents in the raw gas are lower in the case of co-gasification than those from the gasification of lignite alone. Considering the very low reactivity of the char from waste-tyre and the resultant unburned carbon in the ash, the optimal content of the waste-tyre admixture in the gasified feed should not exceed 10 wt.%, whereas short-term increases of up to 20 wt.% will not cause any technological problems or significant economic losses.     

Behaviour of bone origin hydroxyapatite at elevated temperatures and in O2 and CO2 atmospheres

In the present work the behaviour of HAp extracted from pig bones at elevated temperatures up to 1000 °C in O₂ and CO₂ atmospheres has been studied. It has been found that CO₂ atmosphere arrests HAp decomposition. Chemical analysis and infrared spectroscopy reveal that no free CaO appears and no decrease of CO₃⁻² group concentration occurs in the material calcined in CO₂ atmosphere. In the O₂ atmosphere at elevated temperatures, CaO and CO₂ are emitted from the samples, although the remaining material retains the HAp structure as indicated by the X-ray diffraction.     

Inhibitive and residual protective effects of benzimidazole derivative upon acid corrosion of iron

The inhibitive and residual protective effects of an organic inhibitor, benzimidazole derivative, were studied. The protective effect K increased with the increasing concentration of the compound. The coefficient of the residual protective effect K _t of the inhibitor and its mixture with anions is a linear function of time. The time of the residual protective effect τ is a linear function of the inhibitor and anion concentration.