Vol. 20, No. 1 (1964)
RELATIONS BETWEEN COUPLING COEFFICIENTS OF WAVEGUIDES WITH DIFFERENT SURFACE IMPEDANCES AND ITS APPLICATION
1964, 102 (1): 1-10. doi: 10.7498/aps.20.1
In this paper, on the basis of the concept of the impedance purtubation, the principle of invariance of the square of the coupling cofficients proved by Unger is generalized. With this generalization, it becomes simpler to compute the random tolerances with small correlation distance and the discrete tolerances. Unified formulas are derived for computation of various tolerances of waveguides. In addition, relations between relevant pairs of coupling coefficients are obtained.The added attenuation due to an arbitrary form of uniform irregularity is expressed in terms of the maximum allowed impedance perturbation.Numerical examples are given.
1964, 102 (1): 11-18. doi: 10.7498/aps.20.11
By using the integral representation of Green function and δ function, it is very easy to separate the angular and radial variables and obtain an explicit expansion.
The rest-mass effects of the muon's neutrino are discussed. The influence on the two processes-the radiative decay of π mesons and the muon-electron annihilation-in which these effects are exhibited appreciably is analysed in detail. It is shown that no conflict with existing experimental data would arise from assuming the muonic neutrino to possess a finite, not too small rest-mass. Observations for a more accurate evalution of the rest-mass of the muonic neutrino are also suggested.
1964, 102 (1): 33-40. doi: 10.7498/aps.20.33
The problem of focusing high current electron beam in a multi-electrode electron gun with magnetic field has been analysed theoretically. The cathode of the gun may be partially shielded magnetically. The paraxial-ray equation for describing the electron trajectory in the accelerating region is solved in closed form. The space charge effect has been included.
In this article the properties of resonance cavity, operating condition, and radiation output of optical pumping laser are discussed. Factors affecting the operation and the resultant emission are analysed in detail. Evaluation standard for resonance cavity and active media are described. Cavity constructions for limiting the resonance to one or several modes are suggested, hence, photon degeneracy or brightness of light flux in unit frequency range may be increased by several orders of magnitude. Experimental results on the Ruby laser obtained in our laboratory are given. The interpretations of angular distrubution of light frequency, proposed by the auther, can be used to account for some experimental results published by recent investigertors.
INTERNAL FRICTION PEAKS ASSOCIATED WITH THE COHERENCY OF THE DECOMPOSITION PRODUCTS OF HIGH-CARBON AND LOW-CARBON MARTENSITE
1964, 102 (1): 72-82. doi: 10.7498/aps.20.72
Previous studies showed that internal friction peaks appear around 130℃ and 150℃ in the process of tempering of high-carbon and low-carbon martensite respectively. These peaks have been assumed to be associated with the coherency existing between the decomposition product and the parent phase. In the present work, systematic studies are made on the appearance and disappearance of the respective internal friction peaks in correlation with the formation and the destruction of the coherent decomposition products of high-carbon and low-carbon martensite.Results show that these peaks are definitely related with the coherency of the decomposition products.Experimental results show further that, in the case of high-carbon as well as low-carbon martensite, the position of the internal friction peaks (when expressed as a function of temperature) does not change with a change of the frequency of measurement, but the height of the peaks increases with a raise of the stress amplitude used in the measurement. This indicates that the observed internal friction does not involve a relaxation process, and this may be characteristic for all internal friction peaks associated with a coherency phenomenon. On the basis of the behaviour of the peaks, we may assume that the peaks are associated with the stress-induced movement of the coherent boundaries. The origin of the temperature variation of this internal friction is discussed.