Using Amplitude Analysis of Acoustic Emission Signals under Cyclic and Static Loading of Steel Samples

Russian Journal of Nondestructive Testing - The results of amplitude analysis of discrete acoustic emission signals from developing sources such as fatigue cracks are presented. The studies were...     

Reconstruction of diffusion coefficients in the problem of carbonitriding

The uniqueness of the determination of carbon and nitrogen diffusion coefficients is found for the process of carbonitriding with complete and abbreviated information on the concentration fields.M. V. Lomonosov Moscow State University, Russia. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 66, No. 4, pp. 480–483, April, 1994.     

Solution of the problem of oscillations of laminated plates in geometrically nonlinear statement

The article deals with the problem of oscillations of laminated plates with large deflection. It analyzes the fields of application of the refined theory of shear for its solution.Translated from Problemy Prochnosti, No. 8, pp. 47–52, August, 1993.     

A technique for acoustic-emission testing of the wheel pairs of a freight-car carriage

A testing technique developed for determining the acceptance levels of different inspected zones of a wheel pair is considered. It has been shown that the acceptance levels are individual for different inspected zones and are set on the basis of the statistical data obtained during the tests of wheel pairs containing flaws detected beforehand. A test record sheet containing coordinates of flaws and comments on their hazard is issued during automated acoustic-emission testing of the wheel pairs of a freight-car carriage.     

Effect of prolonged high-temperature loading on the structure of the KhN65VMTYu alloy

A complex analysis of changes in the structure and in the phase composition arising as a result of both a prolonged operation of articles made of the alloy KhN65VMTYu (EI893) and after conducting imitation tests of model samples. The tests for long-term strength using samples cut out from the body of a large-dimension turbine blade which was exploited for 63 622 h showed that the blade preserved a significant residual reserve of service life (at 750°C and 250 MPa, the time to failure is 4243.5 h).     

The effect of disinfecting agents on the contact corrosion of medical instruments

The contacts of a tin-lead solder (IIOC 61) with copper, brass and nickel in various types of disinfectants are investigated as galvanic couples where the solder always functions as the anode. The maximum relative increase in the corrosion rate is observed in a weakly alkaline hembar solution (guanidine-based biocidic polymer compound). The active oxidizers contained in delaxon and chlorantoin solutions can decompose due to their reduction at the cathodes of the couples. Original Russian Text ? E.K. Sevidova, I.D. Roi, I.I. Stepanova, 2006, published in Zashchita Metallov, 2006, Vol. 42, No. 3, pp. 326–328.     

Approach to the construction of the generalized functional-semantic cyber security model

In this paper, the functional-semantic model of cyber security is proposed as an initial step towards the development of a new unified methodological cyber security basis. This model makes it possible to formalize requirements for confidentiality, integrity, and availability, as well as to obtain ontological knowledge inferences about the system security state.     

Effect of ionizing radiation on the extraction of Am(III) with <Emphasis Type="Italic">p-tert</Emphasis>-butylthiacalix[4]arene from alkaline carbonate solutions

The effect of γ-irradiation of tert-butylthiacalix[4]arene (TCA) solutions in m-nitrobenzotrifluoride (NBTF) and tetrachloroethylene (TCE) on the extraction of ²⁴¹Am from alkaline carbonate solutions was studied. TCA itself remains stable upon γ-irradiation of its solutions in NBTF to a dose of 200 kGy, but the diluent undergoes strong degradation. The radiation resistance of TCA in TCE is considerably lower: A dose of 70 kGy causes complete degradation of TCA. In the TCA–TCE–aqueous phase system, sulfate ions appear upon γ-irradiation as the final product of the extractant radiolysis. A large number of γ-radiolysis products of TCE and TCA were detected by HPLC and GCMS. The products of radiolysis of TCA in TCE, compared to the initial extractant, have lower molecular mass and higher polarity. The results show that chlorinated diluents are not promising diluents for thiacalixarene in extraction processing of alkaline high-level waste.     

Multichannel Strain-Gauging System Equipped with Microprocessor for Strength Measurements of Structures

The structure of a 64-channel microprocessor strain-measuring system designed for operation with strain gauges and thermal transducers is discussed. The system measures strain and temperature during strength and thermal-strength tests of structures of machines and buildings. The computer codes have been designed in the Borland C++ Builder medium for operations with isolated transducers (1/4-bridge mode), and in the modes 1/2-bridge, bridge, and thermal transducer. The system has been certified. The paper describes examples of its practical utilization in strength tests of struts of the Tupolev-154B airliner and of the undercarriage foreleg of an aerobatic airplane.     

Monitoring of welding aerosol compositions (a review)

Physicochemical properties inherent in the solid component of welding aerosols (SCWA) are characterized. The features of SCWA sampling are considered. Methods are indicated which are most commonly used for the analysis of SCWA in Russian and foreign analytical practice. Destructive and nondestructive methods of SCWA analysis are compared, and their advantages and disadvantages are noted. By particular examples, it is shown that because of the complexity of phase and chemical composition of SCWA samples, rather frequently, one observes a loss of monitored elements in the course of the decomposition of exposed filters. Techniques for making synthetic calibration samples are considered for both classes of methods. In the case of using the X-ray fluorescence method, it is difficult to prepare calibration samples adequate to real SCWA samples collected on a filter. The comparative variant of neutron activation analysis involves synthetic mixtures for the calculation of the content of analytes containing one or two components. Metrological characteristics are presented for SCWA analysis techniques.