Decreasing the waste in metal-heating processes

Results of laboratory development and industrial application of general-purpose coatings for the bricklining of heating furnaces are presented. On the basis of the operating characteristics of the coatings, the effectiveness of their use in furnaces is estimated. The best type of coating, IVAKS-2, is selected, which gives a decrease in the fuel consumption in a soaking pit by 10% and lowers the amount of effluents of nitrogen oxides and carbon oxide by 27% and 20%, respectively, thus improving the waste indices of the processes of metal heating. The IVAKS-2 coating is recommended for wide use in high-temperature heating furnaces of metallurgical and mechanical engineering enterprises. Translated from Ogneupory, No. 4, pp. 19 – 22, April, 1994.     

An Energy Source Based on Helical Explosion–Magnetic Generators for High-Impedance Loads

A transportable standard module developed at the Institute of Experimental Physics as a component of an energy source for modeling current pulses of positive lightning is described. The source is designed as a combination of several unified helical explosion–magnetic generators with output transformers and an inner diameter of the stator of 200 mm. According to our calculations, the source generates current pulses with an amplitude of up to 100 kA in loads with an inductance of 100 H and a resistance of several tens of ohms. The results from testing a typical module operating with a circuit having an inductance of 100 H and a resistance of 4 are presented. The experimental data coincide well with the results of a mathematical simulation of the module's operation.     

A Helical Magnetic-Cumulation Generator with a Compact Transformer

Experimental data on a helical magnetic-cumulation generator with an output step-up transformer formed by two coaxial solenoids is presented. The inner diameter of the helix is 50 mm. Compared with the transformers described earlier, this transformer has a smaller size. The transformer can feed an energy of 1 kJ into a 100-H high-impedance load.     

A method for measuring spectral and time characteristics of mixed pulsed gamma-neutron fields with scintillation and Cherenkov detectors with nanosecond time resolution

A method for measuring spectral and time characteristics of pulsed mixed (n, γ) fields is described. The essence of this method is that a sequence of signals from individual (n, γ) particles registered by (n, γ) detectors is written in a computer with the subsequent amplitude-time analysis of the signal parameters. Fast scintillation and Cherenkov detectors with FWHM of pulses of ～1.5 and 2.5 ns, respectively, are used as (n, γ) detectors. A TDS-3054 broadband digital oscilloscope records signals and transmits them to the computer through a GPIB-USB interface. The equipment used ensures efficient detection of (n, γ) particles at detector counting rates of up to ～2 × 10⁸ pulses/s. The efficiency of this method has been tested in measurements of characteristics of (n, γ) radiation fields from an ИНГ-031 pulsed neutron generator and from a copper target irradiated with a beam of carbon nuclei with an energy of 200 MeV/amu from the TVN-ITEF acceleration-storage complex.     

Production of high-magnesia fluxes and extension of converter-lining life: Part 2

Research on the use of high-magnesia fluxes in (160?C400)-t oxygen converters reveals the influence of the smelting parameters, the composition of the metal and the slag, and the working temperature on the assimilation of MgO from the flux. Slag formation and the removal of sulfur and phosphorus are considered, as well as the influence of magnesia slags on lining wear in the converter.     

Systems analysis of the viscoelasticity of polyester fibres

A comprehensive study of the mechanical properties of polyester fibres and other polymeric materials and prediction of deformation processes are only possible with systems analysis of the viscoelasticity of polymers. In determining the mechanical characteristics of polymeric materials and predicting the deformation processes that take place in them, selection of the mathematical model plays a role of no little importance. Although the deformation processes of one group of materials are more accurately predicted with one mathematical model, another mathematical model can be better for another group of materials. The broader the set of mathematical models and corresponding methods, the more accurately the mechanical characteristics of polymers can be determined and the more accurate the prediction of deformation processes will be. Both in selecting the mathematical model and in predicting the mechanical properties of polymeric materials, computerization of the calculations, which ensures reaching a higher level of investigation of the properties of the materials, plays a role of no little importance. __________ Translated from Khimicheskie Volokna, No. 1, pp. 62–65, January–February, 2007.     

Estimating the parameters of chemical kinetics equations from the partial information about their solution

The inverse problem of identifying the parameters of sets of ordinary differential equations using experimental measurements of three functions that correspond to some components in the vector solution of a set is considered. A private case that is important for applications of chemical and biochemical kinetics when reduced equations linearly depend on the combinations of initial unknown parameters has been studied. An analysis and the numerical results are presented for two types of sets of chemical kinetics equations, such as the Lotka–Volterra model that describes the coexistence of a predator and a prey and the chemical kinetics equations that model enzyme catalysts reactions, including the Michaelis–Menten equations. The search for unknown parameters is confined to the problem of minimizing a quadratic function. In this case, the reduced differential equations of systems are used instead of their vector solutions, which are unknown in most cases. The cases of both stable and unstable search for unknown parameters are analyzed.     

Variation in resistance of a nitrogen-enriched silicon layer as a result of the long-range effect of ion implantation

An improvement in the insulating properties of a synthesized silicon nitride layer under the influence of ion-beam treatment of the back surface of silicon wafer was detected. This result is consistent with the infrared-spectroscopy data obtained previously and is related to the long-range effect of ion implantation.