We adopted Hu Ning's expression of pseudo-energy-momentum tensor density for the gravitational field. From it, we obtained a regular result of the energy of a double-star system. But the distribution of this energy in space cannot be determined uniquely and its distribution laws are essentially identical to those of Schwarzschild external field of an isolated static star. If we recognize that the ...
In this paper, Nyquist diagrams of cyelotron instabilities caused by plasma streams are analysed. The calculation method on instability criterions of ns(the electron density of plasma stream), n0(the electron density of static plasma), B(the applied magnetie field strength), h(the wave number), V(the stream velocity) and T(the temperature) are developed. The numerical results of hydrogen plasma ar...
The physical behaviour of an incoherent-light illuminated optical imaging system is investigated. The result obtained is that there is a coherent region in the reference spherical surface of entrance or emergent pupil which is corresponding to a certain spatial frequency. The author explained the physical characteristics of incoherent optical transfer function sufficently, and suggested a possibil...
According to the principles of theoretical dynamics and the method of mathematical analysis, the mass, centroid and moment of inertia for 45° sean mirror are calculated exactly. The starting power of motor is also computed. Furthermore, The calculation of statical and dymamical equilibrium of 45° sean mirror are also conducted. The results are satisfactory.
The multipole fields are widely used in electron-optical devices and instruments. The multipole fields are generated by several azimuthaly-arranged electrodes or pole-pieces and, are thereby not rotational symmetric. They generally possess some planes of symmetry or anti-symmetry.The Fourier-transform method is used to decompose the three dimensional potential distribution into a series of indepen...
The present paper has proposed a shell model to describe clad particles of superconductors. The model describes the particles as consist of two parts, i.e. a shell part and a nuclei part. According to the conclusion of the solution of Eliashberg equation in inhomogeneous systems we add the spectrum functions of the two parts together with specific weights. We have calculated the Tc of Pb, Sn, In c...
Strontium sodium lithium niobate (SNLN) single crystal possesses good electro-optical properties, but at room temperature only its metastable phase can be obtained. An eutectoidal decomposition will take place when the grown crystal is cooled slowly across the eutectoid horizontal which is about 1200℃. Single crystal up to 10 mm diameter and 15 mm in length were grown by the Czochralski method. La...
The electro-optic, pyroelectrie, dielectric and piezoelectric properties of single crystal strontium sodium lithium niobate which was grown by Czochralski technique have been investigated. The temperature dependence of the half-wave voltage is closely relevant to lithium content in the crystal. The measured pyroelectric coefficient (7×10-8c/cm2·k) is nearly equal to that of SBN (Ba~0.5) at room te...
In this article, starting with the depiction of the crystal structure, the relationship between the crystallization habit of the synthetic quartz and the physical and chemical conditions for its growth is described. The author puts forward a viewpoint that the simple form of the trigonal trapezohedron plays an important role during the growing period. By means of analysing the crystallization habi...
Beyond the upper limit of the linear region of an ionization gauge, there is a falloff in the ion current with the increase of the measured pressure. This nonlinear behavior is to be expected by the theory of non-self-sutaining discharge, from which it follows that the pressure corresponding to the maxium of ion current may be expressed as p=E/C, where E is the field strength between the electrode...