Effect of irradiation with low-energy Ar ions on the characteristics of the working and rear sides of single-crystal GaAs substrate

Contactless methods were used to study the characteristics of the front and rear sides of single-crystal GaAs wafers whose rear side was irradiated with low-energy Ar ions. Variations in the optical and photoelectric properties of irradiated and unirradiated sides were detected. A solitonic mechanism for the penetration of defects into the crystal bulk is suggested.     

Oscillations in a bounded volume of reacting gas suspensate

Sverdlovsk. Translated from Fizika Goreniya i Vzryva, Vol. 27, No. 1, pp. 82–88, January–February, 1991.     

Construction of plastoelastic loading diagrams of structural steels based on magnetic properties

A model of plastoelastic strains of steels was constructed based on the values of the coercive force. The model was successfully applied to specimens constructed from Ст.Зсп steel after different regimes of hot rolling.     

Effect of microalloying on the elastic properties of titanium alloy VT14

Conclusion Rhenium exerts the greatest influence on improvement in the elastic properties of titanium alloy VT14 with microadditives: when its content is 0.005–0.010%, the elastic limit is increased by 10–20%, and the relaxation resistance by a factor of two; in this case, the fatigue strength remains virtually unchanged.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 3, pp. 39–40, March, 1988.     

THz Gyrotron and BWO Designed for Operation in DNP-NMR Spectrometer Magnet

Dynamic nuclear polarization (DNP) in high-field nuclear magnetic resonance (NMR) spectroscopy requires medium-power terahertz radiation, which nowadays can be provided basically by gyrotrons with superconducting magnets. As the electron cyclotron frequency is very close to the frequency of electron paramagnetic resonance for the same magnetic field, under certain conditions the gyrotron can be installed inside the same solenoid used for NMR spectrometer. This eliminates the need for an additional superconducting magnet, results in a shorter terahertz transmission line, and can make DNP systems practical. In addition to an extremely low-voltage gyrotron (“gyrotrino”), we analyze also advantages of strong magnetic field for a slow-wave electron device as an alternative terahertz source.     

A QRS-complex detector of the electrocardiogram signal for the long-term monitoring of the patient’s condition

A procedure for detection of the QRS complexes of electrocardiogram (ECG) signals for systems of long-term monitoring of the patient’s condition based on successive use of the band-pass filtering, the Hilbert transform, and an adaptive threshold algorithm is considered. The efficiency of different QRS-complex detectors has been investigated for model ECG signals in the presence of interferences of various nature and intensity. The efficiency of the proposed procedure has been additionally tested using various clinic records of ECG signals from the MIT Physionet database.     

Connection between diamagnetic and physicomechanical properties of fibres

Conclusions Measurement of the diamagnetic anisotropy of man-made fibres permits one, in a number of cases where fibre defectiveness does not play a decisive role, to evaluate their strength in extension.The interconnection between strength and diamagnetic anisotropy, in the general case, is caused by their identical dependence on the mean degree of molecular orientation of the fibre-forming polymer, and also on the character of the chemical bonds in the main chains.Translated from Khimicheskie Volokna, No. 6, pp. 23–24, November–December, 1989.     

Precision Laser Welding of Silica Glass with Iron-Nickel Alloy

Glass and Ceramics - The possibilities of strong local bonding of glasses and metals with close linear thermal expansion coefficients by means of welding using a femtosecond laser beam were...