Increasing the accuracy of evaluation of the inverse density function for a wide class of unknown distributions of measurement errors

Translated from Izmeritel'naya Tekhnika, No. 1, pp. 7–8, January, 1991.     

Effect of the rise rate of nanosecond high-voltage pulses on the breakdown of air gaps

The breakdown velocity increases to 10–20 cm/ns when the leading edge of the negative voltage pulse decreases to 0.5–2.5 ns. The sharp increase in the velocity can be explained by the appearance of a short-pulse beam of high-energy electrons which produce in the gap a sufficient number of initial electrons. Pis’ma Zh. Tekh. Fiz. 25, 74–80 (September 26, 1999)     

Quasi-distributed recirculation fiber-optic temperature sensor

The new structure of the quasi-distributed fiber-optic temperature sensor is offered, based on recirculation frequency registration a single pulse with its periodic regeneration on different wavelengths and allowing simultaneously to spend measurements to ten points. Fiber-roptic sensor was constructed as a closed optoelectronic contour formed by a source of radiation, an optical fiber delay line, spectral reflective elements, photoreceiver and regeneration block. The sensitive element of this device was the optical fiber. The error of temperature measurements does not exceed 0.2°C at measurement time 1 s, thus the maximum length of the fiber-optic measuring converter reaches 15 km at use multimode gradient optical fiber.     

A steady viscous-thermogravitational flow of capillary liquid and heat transfer in a vertical cavity under asymmetric heat conditions

The problem of joint forced and free laminar convection and heat transfer for liquid with a variable viscosity under a linear temperature distribution between surfaces of a vertical two-dimensional channel is solved analytically. The dependences obtained manifest a strong difference (upon a relatively small variation in viscosity) of the distributions of velocity, friction drag coefficient, and heat transfer from the case of the full Boussinesq approximation while solving problems of mixed convection.     

Modernization of self-feeder of carding machine for production of nonwoven materials

Partial modernization of the system for automatic control of the process of feeding and producing a fibrous product into the self-weight of a Befama CS-412 carding machine has been accomplished. An improved functional system for control of high-speed carding lattice operation regime, which ensures the set technological procedures, has been developed.     

Filtration of suspensions through a multilayer medium in nonlinear kinetics of mass transfer. 1. Theoretical part

The paper has presented strict theoretical relationships for calculating volumetric concentrations of a sediment and suspension, head losses and characteristic times (medium protection action and the achievement of maximum allowable head losses) in the multilayer medium in nonlinear kinetics of mass transfer and constant filtration rate. In addition, in the particular case of the two-layer medium similar formulas have been given as applied to linear kinetics.     

The development of technology and equipment for extracting actinides from radioactive waste reservoirs

Methods of reprocessing the radioactive silt from reservoirs in order to minimize the volume of waste and to fix the radionuclides are investigated. It is shown that it is possible to compact the suspensions into a granulated product, the volume of which is 15–20 times less than the volume of the silt. The process can be realized using different methods of compressing the silt. Preliminary fixing of the radioactive hydroxide suspensions in the form of granulated hydroxides and oxides ensures safe storage of the waste. When analzing methods of dealing with reservoirs it is best to organize silt reprocessing on the spot reliable consolidation and burial. State Scientific Center of the Russian Federation-VNIINM im. A. A. Bochvara. Translated from Atomnaya énergiya, Vol. 86, No. 6, pp. 453–457, June, 1999.