Phase composition of microspheres for production of heat-insulating corundum ceramics

The phase composition of hollow fused corundum microspheres is investigated. The problem of the presence of extraneous phases and their removal is discussed. The effect of heat treatment on the phase composition of the microspheres is studied. Translated from Steklo i Keramika, No. 4, pp. 22–23, April, 2000.     

Strengthening of corundum ceramic with additions of nanopowders

An experimental estimate is provided of the possibility of improving the strength properties of materials prepared from Al₂O₃ traditional for ceramic technology by introducing into them additions of nanosize particles of the same composition. Dependences are obtained for the strength and density of corundum ceramic on the amount of added Al₂O₃ nanopowder.     

The Korund-201-TL dosimetry system for radiation monitoring

This paper presents a brief overview of existing personal dosimetric systems that are based on thermally stimulated luminescence. The new Korund-201-TL automated thermoluminescence system is described.     

Characteristic aerodynamic features of nonsymmetric jet flows

We present results from an experimental study of the relationship between the angle of jet rotation and the curvature radius and length of a rectangular curvilinear nozzle.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 59, No. 2, pp. 186–188, August, 1990.     

Effect of dispersity of Al and C powders on the electric conductivity of plasma in a pulsed MHD-generator operating on powdered fuel

Tomsk. Translated from Fizika Goreniya i Vzryva, Vol. 28, No. 1, pp. 66–69, January–February, 1992.     

Electronic density of states at the interface between silicon and lead borosilicate glass

The density-of-states distribution in the band gap of Si at the interface between Si and lead borosilicate (SiO₂-PbO-B₂O₂-Al₂O₃-Ta₂O₅) glass was assessed byC-V measurements. It is shown that reducing the temperature at which the passivating glass coating is applied decreases the interfacial density of states to a level comparable with the density of surface states on thermally oxidized Si.     

Distinct stability of recombinant L and H subunits of human ferritin: calorimetric and ANS binding studies

Thermodynamic and pH stability of recombinant human L- and H-ferritins were probed by differential scanning calorimetry and 8-anilino-1- naphthalenesulfonate (ANS) binding in the pH range 2-7. At pH 2.0-2.8 they were dissociated into subunit monomers and in this pH interval the H-subunit displayed a single calorimetrically-revealed domain with properties of a molten globule-like state: low enthalpy (6.3-8.0 J/g or 169-172 kJ/mol) and Tm of thermal unfolding (approximately 50 degrees C), a wide transition range (approximately 20 degrees C) and high ANS binding. In contrast, at pH 2 the L-ferritin subunit showed two calorimetric domains with Tm of 35 and 40 degrees C with similar unfolding enthalpies and with moderate extent of interactions, as indicated by the ratio of calorimetric enthalpy (293.9 kJ/mol) and van't Hoff enthalpy (174.2 kJ/mol) for the thermal transition. A pH increase from 2.0 to 2.8 determined the coupling of the two domains into a single cooperative folding unit and drastic increase of the transition temperature (from 37 to 80 degrees C). The contacts between the two domains in the L-subunit appeared to contribute to about 30% of the total stabilization free energy. The unfolding enthalpies, heat capacity changes and pronounced ANS binding of the L-subunit at pH 2.0- 2.8 indicated that part of the structure lacked 'meltable' tertiary interactions. The results indicate that H- and L-subunits are stabilized by largely different intra-chain interactions with a critical contribution to L-subunit stability of embedded salt bridge(s) absent in the H-subunit.      

Thermal protection of an area from an incident gas jet

Results are offered from an experimental study of the decrease in thermal effect of a jet upon a normally oriented surface produced by introduction of cold air or water into the central portion of the jet.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 62, No. 4, pp. 555–558, April, 1992.