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961.
Industry widely uses rotary valves and blow tanks for the pneumatic conveying of products, each having their pros and cons depending on the specific application. This article shows the differing results obtained when low-velocity conveying a product through a common pipeline using both a drop-through rotary valve and a bottom-discharge blow tank feeder. A number of issues arise in the rotary valve system, the main one being rotary valve air leakage. A blow tank system, on the other hand, does not leak, as it is an enclosed system. The experimental results show dramatic differences in product throughput. Further exploration leads to a novel modification being made to the rotary valve system in an attempt to increase its capacity. The result of this modification shows a slight increase in output tonnage, but still significantly less than that obtained from the blow tank. 相似文献
962.
The results of the analysis of variations in the radiative recombination coefficient with varying doping level and concentration of excess electron-hole pairs are reported. It is shown that, along with the effect of narrowing of the band gap calculated in the many-electron approximation, the effect of screening of the Coulomb interaction responsible for the decrease in the excition binding energy should be taken into account. Both effects produce similar trends and decrease the radiative recombination coefficient with increasing levels of doping or injection. The contributions of excitonic radiative recombination and band-to-band radiative recombination to the total radiative recombination coefficient are separated from each other. It is shown that, in the region of room temperature, both contributions are comparable, while at liquid-nitrogen temperature, the excitonic component dominates over the band-to-band component. The results obtained by refined calculations of the limiting value of the internal quantum yield of electroluminescence for the silicon diodes and p-i-n structures are presented. It is shown that the internal quantum yield of electroluminescence can be as high as 14%. However, this values sharply decreases with increasing surface recombination rate and decreasing lifetime of excess charge carriers in the bulk. 相似文献
963.
964.
A. P. Vasil’ev V. P. Vasyukhno M. E. Netecha V. L. Vysotskii R. I. Kalinin A. A. Sarkisov A. Yu. Kazennov Yu. V. Sivintsev A. M. Chernyaev 《Atomic Energy》2006,101(1):506-511
The radioecological conditions which developed on the territory over the long operating time of the object of the naval fleet
in Guba Andreev are described. The results of an analysis of the sources of the real and potential danger and measures to
prevent dangerous effects for the environment and the workers at the time remediation work is performed are discussed.
__________
Translated from Atomnaya énergiya, Vol. 101, No. 1, pp. 49–55, July, 2006. 相似文献
965.
The Schaal or Oven Test, originally developed by the biscuit and cracker industry to provide a relative rating for stability
of various shortenings, has been generally adopted by shortening manulacturers. Advantages as well as limitations of the test
are enumerated. It is possible to estimate the Oven Test by determining peroxide development in the test sample after two
to four days in the oven. Oven Tests may also be conducted without having determined them organoleptically by observing the
color change at the point of extreme rancidity. Peroxide formation occurring in a fat contained in biscuits or crackers when
subjected to the Oven Test has been investigated and a simple and rapid method of extracting the fat, without changing its
peroxide characteristics, has been devised.
Lever brothers company 相似文献
966.
M. I. Surin V. E. Keilin S. M. Miklyaev S. A. Shevchenko 《Instruments and Experimental Techniques》2008,51(4):634-637
Within the framework of the “International Thermonuclear Experimental Reactor” (ITER) program, a prototype of a superconducting magnet for a 170-GHz gyrotron has been developed, manufactured, and tested. The operating induction value (7.1 T at the center of a 219-mm-diameter cold hole and 8.1 T on the winding) is reached at a current of 185.2 A. In the final version of the magnet, the required induction value was reached without aging. Special requirements are imposed on the distribution of the magnetic field along the axis, including an abrupt field decrease on both sides of the magnet. Axial forces are additionally taken by a special device. The magnet’s sections are wound with multifiber conductors based on niobium-tin and niobium-titanium alloys. Seventeen resistive shunts are provided for protecting sections during their transition to the normal state. The magnet is equipped with a device for removing a part of energy from the sections. Mechanical stresses in the magnet’s sections and the structure’s power elements have been measured during tests. 相似文献
967.
M. E. Borodyanskii I. M. Borodyanskii T. A. Martyshchenko 《Instruments and Experimental Techniques》2008,51(3):392-395
A device for measuring the active resistance of a direct current energized circuit section is described. Owing to the use of up-to-date electronic components, an iteration measurement algorithm, and a sinusoidal signal as a test one, the following performance characteristics have been obtained: the measurement time is <1 s, and the error varies from 0.3 to 2.0% in a 100-Ω to 1-MΩ range and ≤25% in 10-to 100-Ω and 1-to 10-MΩ ranges. 相似文献
968.
E. M. Zobov M. E. Zobov F. S. Gabibov I. K. Kamilov F. I. Manyakhin E. K. Naimi 《Semiconductors》2008,42(3):277-280
The results of the effect of ultrasonic treatment of ZnSe crystals on the structure of the energy spectrum of electronic states of centers with deep levels forming photoelectric and luminescent properties of this compound are presented. It is for the first time proved experimentally that the climb of edge dislocations under the effect of ultrasound leads to regrouping and generation of defects forming deep levels, which manifest themselves in phenomena of photosensitivity and radiative recombination. 相似文献
969.
V. F. Ivanov A. A. Nekrasov K. V. Tcheberiako A. V. Vannikov A. S. Posed'ko S. I. Lishik Yu. V. Trofimov 《Journal of the Society for Information Display》2003,11(1):11-14
Abstract— An all solid‐state photoelectrochromic element (PECE) was developed on the basis of electrochromic layers of WO3 and polyaniline with a layer of polymer electrolyte placed on a base of polyamidosulfoacid, in which a thin‐film CdSxSe1?x photoresistor was used as an electronic key. The dependence of the sensitometric characteristics of the PECE on the applied voltage was studied. 相似文献
970.
Polyacrylate gels containing Ag+ and TiO2 nanoparticles are shown to swell under UV light and shrink under visible light in water. In work reported by Tetsu Tatsuma and co‐workers on p. 1249, the TiO2 absorbs UV light and reduces the Ag+, whereas the deposited Ag absorbs visible light and dissolves itself. These redox reactions change the interactions between the polymer chains and eventually the volume of the gel, as shown on the cover. 相似文献