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991.
Conclusions In an MR reactor performance tests of 16 fuel assemblies, with elements having essentially the same structure as standard VVÉR-100 fuel elements, were carried out. Tests of five more fuel assemblies are continuing. Of the 16 assemblies, 13 were studied in a hot laboratory.The tests in the MR, carried out at high loads and with a large number of transition processes, as well as the postreactor studies, indicated that fuel elements of the specified design (with initial helium pressures of 1.96–2.45 MPa) have a high reliability. None of the elements of the fuel assemblies studied malfunctioned due to design defects or faults in their fabrication. During the tests the jackets were subject to a little oxidation and hydrogenation (zirconium-oxide film<3 m thick, hydrogen content less than 0.008% by mass), and their plasticity remained high (the relative elongation at the working temperature remained at the 20% level).Translated from Atomnaya Énergiya, Vol. 62, No. 5, pp. 312–317, May, 1987.  相似文献   
992.
de C. Roseno  K. T.  Antunes  R. A.  Alves  R. M. B.  Schmal  M. 《Catalysis Letters》2021,151(12):3639-3655
Catalysis Letters - The NdM0.25Ni0.75O3 (M?=?Cr, Fe) named NCN and NFN catalysts precursors were synthesized and characterized. The CO2 utilization in the feed was studied in the...  相似文献   
993.
An experimental-numerical method for measuring dynamic crack propagating velocities under stress wave loading is established in this paper. The experiments of the three-point bend specimen are done on the improved Hopkinson bar. Deflection of loading point, dynamic load and instantaneous crack length are measured, then crack propagating velocities are calculated. Experiments on 40Cr steel show that the results given by this method have a good agreement with that obtained by the resistance fracture gage method. Therefore this method is feasible for measuring crack propagating velocities under high loading rate and will have wide application.  相似文献   
994.
Results of experiments performed to isolate the effect of surface roughness generated during slurry erosion-corrosion of 304L stainless steel are presented. Surfaces prepared by grinding to different finishes show that increasing the roughness lowers the pitting potential in chloride solution. Subsequent erosion by an aqueous sand slurry then alters this pitting potential (Ep), as measured in the solution phase alone, in a manner dependent on the initial surface roughness. Surfaces which were initially rougher show a pronounced rise in p after erosion, while those with an initially smoother finish show a fall in Ep after erosion. Measurement of Ep during erosion-corrosion does not fit either process, with values of Ep lower than those predicted from the surface roughness alone.  相似文献   
995.
Metallurgical and Materials Transactions A - Co-based superalloys have been developed as candidate materials to replace Ni-based superalloys in hot sections of turbine engines, however, their...  相似文献   
996.
Russian Journal of Non-Ferrous Metals - The aim of the work is to develop an optimal method for processing Sn–Pb alloy to obtain a marketable product-branded O1?O3 tin (Sn ≥...  相似文献   
997.
Chernov  K. A.  Fomin  A. V.  Glushchenko  A. I. 《Metallurgist》2022,66(1-2):84-95
Metallurgist - The development and implementation of adaptive control systems, which are used to tune the parameters of PI-controllers of the metal pre-heating furnace for rolling and the water-air...  相似文献   
998.
999.
It is known that the corrosion resistance of stainless steel is deteriorated by blasting, but the reason for this deterioration is not clear. A blasted austenitic stainless steel plate (JIS-SUS304) has been characterized with comparison to the scraped and non-blasted specimens. The surface roughness of the blasted specimen is larger than that of materials finished with #180 paper. A martensite phase is formed in the surface layer of both blasted and scraped specimens. Compressive residual stress is generated in the blasted specimen and the maximum residual stress is formed at 50–100 μm from the surface. The corrosion potentials of the blasted specimen and subsequently solution treated specimen are lower than that of the non-blasted specimen. The passivation current densities of the blasted specimens are higher those of the non-blasted specimen. The blasted specimen and the subsequently solution treated specimen exhibit rust in 5% sodium chloride (NaCl) solution, while the non-blasted specimen and ground specimen do not rust in the solution. It is concluded that the deterioration of corrosion resistance of austenitic stainless steel through blasting is caused by the roughed morphology of the surface.  相似文献   
1000.
The solubility of sulfur in chromia has been studied in H2-H2O-H2S tagged with35S at 973 and 1173 K at low oxygen and sulfur partial pressures typical for coal gasification-systems. For monocrystalline samples, it has been shown that sulfur-containing species are only present adsorbed on the surface of the specimens and can be removed by ultrasonic cleaning in acetone. The surface coverage after 4 weeks of exposure to H2-H2O-H2S was between 2.8 and 19.3% of a monolayer. In polycrystalline chromia, sulfur was located only in pores and cracks of the sample. In dense, compact areas of the specimens the solubility of sulfur was below the detection limit of autoradiography, which was estimated to be better than 0.17 ppm.  相似文献   
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