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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
972.
Stability of the zero equilibrium state of a full electromagnetic suspension of a rotor under decentralized control of each bearing is proved. The obtained results may be used for selecting the structure of the system for control of electromagnetic bearings. 相似文献
973.
In the present study, oil palm wood flour (OPWF) particles with less than 250 μm sizes have been used as filler materials
in the woven-glass-fiber reinforced epoxy composite. The hybrid composites were fabricated using a hand lay-up method and
cured at room temperature under a compressive load of 196 N (20 kg). The OPWF of 2.5 to 10 parts per hundred (pph) by weight
was used to evaluate its effect on impact strength of the hybrid composites at a range of temperature from −50 to 50 °C. The
impact strength, evaluated using V-notch Charpy method, showed reduction with increasing filler content up to 5 pph and then
the strength increment in those composites containing more than 5 pph OPWF. More severe damages were found in specimens with
higher filler contents resulting higher energy absorption during impact. The composites with a large amount of OPWF particles
deflected crack propagation paths or created obstacles at the crack tips and increased toughness of the composites. The impact
strength was found to decrease when the samples fractured at subzero temperatures and this happened because of the reduction
of the matrix ductility at lower temperatures. 相似文献
974.
G. A. Shanshurov 《Russian Electrical Engineering》2007,78(9):467-473
A model of an induction motor with an asymmetric stator winding is developed; it may be represented as two phases connected in parallel or in series and displaced is space by some angle. 相似文献
975.
A. P. Petrova 《Polymer Science Series C》2007,49(3):219-219
Listed are the grades of heat-resistant adhesives developed under the Andrianov’s scientific guidance at the All-Russia Institute of Aviation Materials on the basis of organosilicon polymers. 相似文献
976.
977.
H. E. N. Stone 《Journal of Materials Science》1987,22(5):1749-1752
The ratio of the thermal oxidation parameter to the decomposition point (T
p/T
m) is of the order of 0 85 for Y9Co7, indicating a high degree of chemical binding. The persistence of high values of this ratio has been investigated with respect to (a) other compounds in the Y-Co system, (b) replacement of cobalt in Y9Co7 by other d-e!ements, and (c) replacement of yttrium by other rare-earth elements. High ratios are found for (a) Y-Co compounds where Y/Co > 0.5, (b) Y-3d compounds with cobalt and niche! only, end (c) RE-Co compounds generally. However, there are differences in level of the ratio amongst the rare-earth compounds, from which it is inferred that the highest values coincide with full electron shells, that is, without participation of 4f electrons. Additional work is described on an effect of preparation arc-melting current 0n theT
p value for Y9Co7, and on compounds of the same pattern where both components are changed. 相似文献
978.
Raw and heat processed peanut flours were found to contain higher in vitro trypsin inhibitor activity and lectin content than similarly processed soy flour. When fed to weanling rats at a level of 10% protein, the response pattern in food consumption, growth, liver function, and serum chemistries was not consistent among or between the groups. It is concluded that the levels of antinutritional factors in legumes do not correlate with their overall biological impact in feeding studies with the rat. 相似文献
979.
980.