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21.
通过引入新型两指标B值鞅空间, 利用两指标B值鞅的Fefferman不等式, 证明了当B为自反Banach空间时, 由p均方算子定义的两指标B值鞅空间pHα 相似文献
22.
桂质廷(1895~1961),我国著名的地球物理学家.他是建国初期中国科学院地球物理组专门委员,第一个巡测了我国境内地磁常量的中国人.他最先和学生一道在国内进行了高空电离层的常规观测.他所创建的武汉大学游离层实验室,50年来未曾间断电离层的观测研究.本文着重介绍他的生平简历、教学态度、学术成就和爱国主义思想. 相似文献
23.
Mahmood Mian 《Pramana》1993,41(2):145-149
The binding energy of the double hypernucleus
ΛΛ
6
is calculated in α + 2Λ cluster model using the method of translation invariant basis TIMO. As regards the required interaction
potentials we use a density dependent effective ΛN force and a gaussian form for ΛΛ potential. With these interactions a very reasonable value ofB
ΛΛ is obtained if the oscillator states up to the excitation quantum numberN=12 are taken into account in the expansion of wavefunction of the hypernucleus. This value ofN is much smaller than that obtained in an earlier study. This lowering inN value is attributed to a much better choice of ΛN potential used in the present study. 相似文献
24.
高频地波雷达OSMAR2000同步控制器 总被引:2,自引:1,他引:2
根据高频地波雷达(OSMAR2000)的时序要求,给出了利用可编程序间隔定时器82C54产生各种控制信号和同步信号的方法。同步控制器采用可编程器件,所有信号的时间关系均由软件设定,以计数方式产生,不但电路简单,调试修改方便,更重要的是使各信号间的时序关系准确、稳定、可靠。减少了雷达系统的相位误差。 相似文献
25.
本文首先建立球面型空间中度量平均的概念,其次讨论度量平均过程中一些几何不变量之间的关系,最后举例说明度量平均在解决球面型空间中几何极值问题时的应用. 相似文献
26.
Exact solutions for nonlinear Schr?dinger equation in phase space: applications to Bose-Einstein condensate 下载免费PDF全文
The stationary-state nonlinear Schr?dinger equation, which models the dilute-gas Bose-Einstein condensate, is introduced within the framework of the quantum phase-space representation established by Torres-Vega and Frederick. The exact solutions of equation are obtained in the phase space, by means of the wave-mechanics method. The eigenfunctions in position and momentum spaces are obtained through the ‘Fourier-like' projection transformation from the phase space eigenfunctions. The eigenfunction with a hypersecant part is discussed as an example. 相似文献
27.
In this work the Einstein gravitational field equations and the Lichnerowicz boundary formalism in the extra dimensions are used to build up our black hole model from 6-dimensional space-time. From the internal stress-energy tensor the solutions with energy levels and semiclassical space-quantization are obtained, which combines with only one metric condition outside the defect. We show a new type of energy source, which originates from extra dimensions. A part of the energy source of quasi-stellar object (QSO) maybe come from extra dimensions in that way. The theoretical arithmetic upper limit is identical to that of the output energy of QSO. 相似文献
28.
《Current Applied Physics》2018,18(12):1605-1608
Gd1-xHoxNi melt-spun ribbons were fabricated by a single-roller melt spinning method. All the compounds crystallize in an orthorhombic CrB-type structure. The Curie temperature (TC) was tuned between 46 and 99 K by varying the concentration of Gd and Ho. A spin reorientation (SRO) transition is observed around 13 K. Different from TC, the SRO transition temperature is almost invariable for all compounds. Two peaks of magnetic entropy change (ΔSM) were found. One at the higher temperature range was originated from the paramagnet-ferromagnet phase transition and the other at the lower temperature range was caused by the SRO transition. The maximum of ΔSM around TC is almost same. The other maximum of ΔSM around SRO transition, however, had significantly positive relationship with x. It reached a maximum about 8.2 J kg−1 K−1 for x = 0.8. Thus double large ΔSM peaks were obtained in Gd1-xHoxNi melt-spun ribbons with the high Ho concentration. And the refrigerant capacity power reached a maximum of 622 J kg−1 for x = 0.6. Gd1-xHoxNi ribbons could be good candidate for magnetic refrigerant working in the low temperature especially near the liquid nitrogen temperature range. 相似文献
29.
In this paper we give a short geometric proof of a generalization of a well-known result about reduction of codimension for submanifolds of Riemannian symmetric spaces. 相似文献
30.