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951.
952.
This article examines the history and future prospects of the production of iron powders by the atomizing high-carbon melts with compressed air. In terms of their properties, the iron powders obtained by this method are intermediate between water-atomized powders and reduced powders. They can be used to make anti-friction products or structural elements having a density within the range 6.3–6.9 g/cm3. The outlook for these powders is promising in Russia because they are needed for machine construction, especially in the auto industry.  相似文献   
953.
The character of the correlation of the impact elasticity of cast and subsequently normalized and thermostrengthened steels 08XΓΦЛ and 08XΓTЛ with their coercive force is studied. Such a correlation in the form of a curve characterized by a maximum is observed for both low-carbon and low-alloyed hot-rolled steels.  相似文献   
954.
Methods for cleaning commercial T-1500 dielectric oil with different adsorbents are studied. The oil is intended for impregnation of high-voltage pulse capacitors with film dielectric.  相似文献   
955.
The possibility of obtaining high laser output energies at a 1.32-μm wavelength using thin LiNdLa phosphate glass slabs with a high Nd3+ concentration is discussed. In the experiments, 3×14×125-mm slabs were prepared from LiNdLa phosphate glass with a Nd-concentration of 1.2×1021 cm-3. The facets of the slabs were not antireflection-coated. They were tested in a silver-coated quartz tube reflector of 25-mm diameter and pumped by 450-μs pulses from a flash lamp with a 120-mm arc length. In this construction the light, which passes through the slab, returns to it after reflection from the tube surface. Most of the radiation falls on the wider side of the slab at large angles of incidence, thus maximizing its path inside the slab. The quartz reflector was water cooled. The 150-mm laser resonator was formed by two flat mirrors. At 1.32-μm lasing wavelength an output mirror of r=95% reflectivity was used with less than 10% reflectivity at 1.32 μm  相似文献   
956.
The compaction characteristics of selected powders in tapping could be described by either Sone's model or by a single term exponential equation. The Hausner ratio, i.e., the ratio between tapped and loose density, calculated by using these models was found to be a sensitive and useful indictor of the compaction mechanism in different types of tapping tests. The latter, especially where particle attrition was evident, could produce distinctly different compaction patterns. No correlation was found between these powders, Hausner's ratio, and their compressibility in mechanical compaction.  相似文献   
957.
958.
An experimental superconducting magnetic system (MS) with an energy capacity of 5 MJ and an output power of no less than 130 MW is described. The MS winding is sectioned in the axial and radial directions. Owing to sectioning in radial direction, the MS may be used as an adjustable inductance enabling the stabilization of the amperage. The adjustable inductance may also be used as an efficient instrument for leveling the ratio of the active and reactive power in electric mains intended for different purposes (transport, energy industry, and emergency systems).  相似文献   
959.
960.
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