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181.
The operation of a torsional oscillator for detection, of flow-driven textural transitions in, 3He-A is described. The detection technique, tracking the shift of the resonant frequency of the torsional oscillator, allows us to observe textural changes and the presence of vortices in zero magnetic field. It relies on. the anisotropic superfluid density of 3He-A and its change due to reorientation of the Î-texture caused by counterflow. 相似文献
182.
M. I. Danielyan K. S. Kulakov S. L. Kulakov V. L. Tumanov M. E. Kompan 《Technical Physics Letters》2007,33(7):597-599
A considerable (~1.4-fold) increase in the average output power of a chemical current source has been achieved by means of a periodic pulsed manipulation of the load. A scheme used for the pulse-train loading is presented and mechanisms ensuring an increase in the average output power of the current source are considered. 相似文献
183.
L. I. Ognev 《Technical Physics Letters》2007,33(11):972-975
Numerical simulations of the heating of a carbon dust particle (pellet) in hydrogen plasma showed that the character of heating depends in a threshold manner on the initial temperature of the pellet. The heating proceeds at a high rate if the initial temperature is above a certain threshold (“hot” regime), and at a much lower rate for an initial temperature below this threshold (“cold” regime). An important factor in this process is thermionic emission, which leads to positive charging of a pellet in hydrogen plasma due to electron emission from the surface in the hot regime. In the cold regime, the pellet acquires a negative charge that retards the electron flux from plasma to the particle. A method for the experimental observation of this effect is proposed. 相似文献
184.
I. V. Zolotukhin I. M. Golev E. K. Belonogov V. P. Ievlev D. A. Derzhnev A. E. Markova 《Technical Physics Letters》2003,29(12):1006-1008
We have studied the structure and thermo emf of a nanotubular carbon deposit formed in electric arc discharge plasma. The deposit contains flocky granules with dimensions of 15–20 μm within a 20–60 μm-thick layer on the substrate surface. This deposit is characterized by a sufficiently high thermo emf (60 μV/K) and electric conductivity (600 Ω−1 m−1). 相似文献
185.
186.
Yu. A. Brodskii V. I. Bazikov I. V. Zubkov A. I. Krylov V. D. Stepanenko 《Chemical and Petroleum Engineering》2006,42(9-10):552-559
Modern designs are examined, and technical data presented for vibratory electric and convection driers, driers with infra-red sources, and steam driers. 相似文献
187.
In the present study, various diffusive processes have been investigated during foaming of powdered precursors of polyimide. A detailed analysis of the powdered precursor's characteristics allows for an enhanced morphological understanding of the resulting microstructures and foam unit cell. Parameters that are central to the foaming process such as particle morphology, volatile concentration and sorption-desorption processes are evaluated. Isothermal and non-isothermal desorption experiments have been carried out by thermogravimetric analysis (TGA), and specific diffusive processes have been correlated to thermodynamic and kinetic transitions by means of modulated differential scanning calorimetry (MDSC) of the corresponding materials. It was found that two primary fluxes of volatiles, one out of the external surface of the particles (responsible for volatile desorption) and the other into the growing bubble (responsible for vapor supersaturation inside the bubble) compete against each other creating a competitive scenario that becomes the controlling factor for potential inflation within the precursor particles. 相似文献
188.
189.
V. I. Gorynin 《Strength of Materials》1991,23(5):524-527
The influence of the level of defectiveness of design and service origin (grooves and cracks) of a fastener and an impact specimen on the accuracy of determination of the allowable values of the ductile-to-brittle transition temperature is investigated. An evaluation of the allowable ductile-to-brittle transition temperatures making it possible to impose more soundly based requirements for effectiveness of the material in the stages of design, production, and service in relation to the production condition of the steel, the level of defectiveness of the fastener, and the specified operating life of the threaded joint is proposed.Translated from Problemy Prochnosti, No. 5, pp. 35–37, May, 1991. 相似文献
190.
L. M. Aksel’rod V. I. Rumyantsev N. Yu. Korableva N. V. Belykh Ya. G. Dyatlova 《Refractories and Industrial Ceramics》2008,49(2):116-119
Technology is developed for preparing refractory components made of partially stabilized zirconium dioxide using an isostatic
compaction press. Technology is provided for manufacturing dispensing nozzles using combined and separately stabilized zirconium
dioxide, and also indices of the refractories obtained and imported materials are compared.
__________
Translated from Novye Ogneupory, No. 3, pp. 127–131, March 2008. 相似文献