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991.
A. M. Skorobogatov A. V. Tvardovskii 《Journal of Engineering Physics and Thermophysics》2007,80(3):634-637
A model for calculating of the change in the basic thermodynamic characteristics of a sorbent (internal energy and entropy)
with the phenomenological-thermodynamics method has been developed. Calculations for the systems polycarbonate-carbon dioxide
and polymethylmethacrylate-carbon dioxide have been carried out.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 3, pp. 198–200, May–June, 2007. 相似文献
992.
A. D. Bulanov P. G. Sennikov V. A. Krylov T. G. Sorochkina L. A. Chuprov O. Yu. Chernova O. Yu. Troshin 《Inorganic Materials》2007,43(4):364-368
Using gas chromatography and high-resolution Fourier-transform IR spectroscopy, we have determined the concentrations of C1–C4 hydrocarbon impurities in isotopically unmodified silicon tetrafluoride before and after fine purification and in 28Si-enriched SiF4. The concentrations of C1–C4 hydrocarbon impurities in silicon tetrafluoride for SiH4 synthesis have been shown to correlate with those in the synthesized silane. 相似文献
993.
D. L. Kuznetsov E. V. Kol’man Yu. S. Surkov V. V. Uvarin I. E. Filatov 《Technical Physics Letters》2007,33(7):604-606
The process of methane conversion in a mixture modeling the natural gas under the action of a periodic nanosecond pulsed electron beam and an electron-beam-induced non-self-sustained discharge has been numerically simulated and studied in experiment. The possibility of methane conversion under the action of electric pulses without significant heating of the processed gas mixture is demonstrated for the first time. The main conversion products in experiment were hydrogen, ethylene, and acetylene. 相似文献
994.
Peter Su Adrian Gerlich Motomichi Yamamoto Thomas H. North 《Journal of Materials Science》2007,42(24):9954-9965
The formation of local melted films during friction stir spot welding of as-cast AZ91D and thixomolded AZ91 material is investigated.
The average temperatures close to the tip of the rotating pin vary from 438 to 454 °C during the dwell period in friction
stir spot welding. These measured temperature values are higher than the melting temperature of α-Mg + Mg17Al12 eutectic (437 °C). It is suggested that the temperature in the stir zone during the dwell period is determined by the relative
proportions of α-Mg and (α-Mg + Mg17Al12) eutectic material, which are incorporated during friction stir spot welding. Based on the stir zone temperature measurements
and a detailed examination of material located at the root of the pin thread it is suggested that material is moved downwards
via the pin thread and into the stir zone during the dwell period in friction stir spot welding. Evidence of local melted
film formation is observed in the stir zone of AZ91 spot welds. It is suggested that melted films are retained since their
dissolution rate is much slower in the high temperature stir zone than it is when melted films is formed in the stir zone
during Al 7075-T6 friction stir spot welding. The spontaneous melting temperature, solute diffusion rate and the thermodynamic
driving force for droplet dissolution are much higher during Al 7075-T6 friction stir spot welding. 相似文献
995.
Open window buses without air-conditioning are a major mode of urban and inter-city transport in most countries. High occupancy
combined with hot and humid conditions makes travel in these buses quite uncomfortable. In this study air flow through a bus
has been studied that could be the basis for low cost and eco-friendly methods of increasing passenger comfort and possibly
reduce drag. The aerodynamics of such a road vehicle has not been studied as previous investigations have been confined to
vehicles with closed windows that present a smooth exterior to air flow. Using a 1:25 scaled Perspex model of an urban bus
in Delhi, flow visualization was performed in a water channel. The Reynolds numbers were one-tenth of a real bus moving at
10 m/s. Smoke and tuft visualizations were also performed on an urban bus at 40 km/h. Numerical simulations were performed
at the actual Reynolds number. Even though there were Reynolds number differences, the broad features were similar. Air enters
the bus from the rear windows, moves to the front (relative to the bus) and exits from the front windows. Inside air velocity
relative to the bus is about one-tenth of the free-stream velocity. The flow is highly three-dimensional and unsteady. 相似文献
996.
997.
V. V. Mel’nikov 《Journal of Engineering Physics and Thermophysics》2007,80(1):148-158
An integral transformation with the aid of which a solution of the problem of unsteady-state heat transfer in a system of
three coaxial finite cylinders with different boundary conditions on their surfaces depending on space and time is presented.
Each of the cylinders evolves heat of a certain intensity, depending on time and coordinates. A numerical solution of one
variant of the boundary conditions is given and illustrated by figures. The method of transforming the solution of the problem
with other boundary conditions is shown.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 1, pp. 140–148, January–February, 2007. 相似文献
998.
A. A. Khrushchinskii S. A. Kuten’ N. M. Budevich V. F. Minenko O. M. Zhukova N. K. Luk’yanov 《Journal of Engineering Physics and Thermophysics》2007,80(6):1170-1177
Measurements of the beta-activity of milk, serving as the main source of information on the radioactive contamination of the
environment by the iodine isotope 131I, carried out on a DP-100 radiometer in the early post-Chernobyl period (1986) in Belarus, have been mathematically simulated.
The results obtained allow the conclusion that the indicated measurements should be analyzed again with consideration for
all of the nuclides present in milk.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 6, pp. 102–108, November–December, 2007. 相似文献
999.
V. Sh. Shagapov S. A. Lepikhin M. N. Galimzyanov 《Journal of Engineering Physics and Thermophysics》2007,80(6):1206-1209
A steady flow of a bubble gas-liquid mixture in a nozzle having a circular cross section has been investigated. The possibility
of realization of superhigh temperatures and pressures in the gas phase of the mixture in the region near the smallest cross
section of the nozzle has been analyzed. The influence of the initial radius of the flow and the volume content of bubbles,
determining the volumetric rate of flow of the liquid supplied to the nozzle, on the pattern of the flow has been considered.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 6, pp. 134–137, November–December, 2007. 相似文献
1000.
V. P. Beskachko O. A. Golovnya A. E. Korenchenko 《Journal of Engineering Physics and Thermophysics》2007,80(1):132-135
The results of a numerical solution of the problem of vibrations of a torsion viscosimeter filled with an incompressible viscoplastic
liquid are presented. It has been shown that in the vicinity of the rotation axis there appears a dead zone, whose boundary
changes in the process of vibrations. The influence of plastic properties of the liquid on the characteristics of viscosimeter
vibrations has been determined. A method for identifying viscoplastic properties by the observed parameters of vibrations
is proposed.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 1, pp. 124–127, January–February, 2007. 相似文献