Theoretical study of the effect of electrochemical cell inclination on the limiting diffusion current

The effect of inclination of electrochemical cell with plane-parallel electrodes in the gravitational field on the limiting current of electrochemical reaction is theoretically analyzed by the example of iodine-iodide system. The quantitative dependences of the limiting current on the angle α between the electrodes and the horizontal are obtained. It is shown that this effect is associated with the variation in the distributions of solution concentration and hydrodynamic velocity with α. It is found that the ratio between the electrode's length and the interelectrode distance is of great importance.     

Change of the wear resistance of a superhigh-molecular-weight polyethylene plate upon its modification by a mechanically activated ceramic nanopowder

The object of investigation is superhigh-molecular-weght polyethylene (SMWP) with a molecular weight of up to 8 × 10⁶ g/mole and a particle size from 63 to 315 μm obtained by the technique developed at the Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences. The purpose of this work is to create structural polymer materials with high physical and technical characteristics and to extend the scope of the application of this polymer in industry. The problem is solved by the modification of SMWP powder particles via the introduction of nanodispersed ceramic materials. Based on the data obtained, the methods of the production of the article samples from nanocomposite materials based on SMWP via the hot-pressing technique were developed and the influence of the nanomodifiers on the properties of the composite material was studied.     

Study on the Influence of Different Energy Sources on the Structure and Mechanical Properties of a Welded Joint from an EP693 Nickel Alloy

Russian Journal of Non-Ferrous Metals - The results of a study on the influence of types of welding (laser, electron beam, and argon arc) on the properties of a permanent joint made of an EP693...     

Comparison of the frequency of a He-Ne laser stabilized to the central component of the magnetic hyperfine structure of the F2 (2) line of methane

Translated from Izmeritel'naya Tekhnika, No. 4, pp. 18–20, April, 1989.     

On the capacity limits of HVAC duct channel for high-speed Internet access

In this paper, we report theoretical and experimental channel-capacity estimates of heating, ventilation, and air conditioning (HVAC) ducts based on multicarrier transmission that uses M-ary quadrature amplitude modulation and measured channel responses at the 2.4-GHz industrial, scientific, and medical band. It is shown theoretically that data rates in excess of 1 Gb/s are possible over distances up to 500 m in straight ducts in which reflections have been suppressed. Our experimental results also show that even in the case of more complex HVAC duct networks (i.e., HVAC duct networks that include bends, tees, etc.) data rates over 2 Gb/s are possible. Our estimations in this case are valid for distances of up to 22 m, which was the maximum distance of our experimental setup. These experimental results, measured with a large-scale testbed set up at Carnegie Mellon University, Pittsburgh, PA, albeit limited in terms of transmitter-receiver separation distance, provide further evidence on the potential of HVAC systems as an attractive solution for providing communications in indoor wireless networks.