Precipitation of particulate matter from slurry obtained in 1A-1M cat cracker

Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 7, pp. 5–7, July, 1992.     

Startup and steady operating conditions of supersonic diffuser

An engineering method is proposed for calculating the gas dynamics, friction, and heat transfer of steady and nonsteady flows in supersonic diffusers. The calculation results are compared with experimental data for theoretical Mach numbers M=2 and 3 preceding the diffuser.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 61, No. 1, pp. 63–70, July, 1991.     

A Coordinate Detector for Studying Horizontal Fluxes of Cosmic Rays

A DECOR coordinate detector is a multilayer system of plastic streamer tube chambers located around a NEVOD Cerenkov water calorimeter. The basic characteristics of the detector are as follows: the area is 100 m², the angular resolution is 1°, and the space resolution is 1 cm. The structure of the detector, data acquisition and trigger systems, and results obtained during the operation of a pilot assembly (8 chamber layers and a working area of 8.4 m²) are given.     

Selective Electrocatalysis on Platinum Nanoparticles with Preferential (100) Orientation Prepared by Cathodic Corrosion

The “cathodic corrosion” method for nanoparticle synthesis has been used to produce Pt nano-crystals with a preferential (100) orientation. These particles are surfactant-free and electrochemically clean, featuring a significant percentage of (100) terrace sites, as confirmed by electrochemical characterization tests to establish the amount of (100) sites: blank voltammetry in H₂SO₄, adsorbed CO stripping, and Ge irreversible adsorption. The high catalytic activity of these preferentially oriented particles is confirmed for reactions preferring (100) sites, such as dimethyl ether oxidation, ammonia oxidation, and nitrite reduction in alkaline media. In the case of nitrite reduction it is demonstrated that, similarly to (100) terraces of a well-ordered Pt single crystal electrode, the (100) facets of the nano-crystals can steer the reaction towards the selective formation of N₂. The use of an inexpensive preparation method to obtain nano-electrocatalysts that can perform selective electrocatalytic reactions such as ammonia oxidation and nitrite reduction, can pave the way for a new generation of practical catalysts for environmental and energy purposes.     

Passive harmonic modelocking in monolithic compound-cavity laserdiodes

Passive harmonic modelocking operation of novel compound-cavity laser diodes is demonstrated. The modelocking rates can be readily scaled up into the terahertz domain and enable applications in terahertz imaging, medicine, ultrafast optical links, and atmospheric sensing     

Global reconstruction from nonstationary data

One-dimensional time series of a dynamical system with slowly varying parameters are investigated. For estimation of the characteristics of the attractors of such a system which exist for fixed values of the parameters, it is proposed to “cut out” from the time series short segments that belong to the individual attractors and to use them to reconstruct a model dynamical system. Pis’ma Zh. Tekh. Fiz. 25, 74–81 (May 26, 1999)