bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ENERGY OF DOUBLE-STAR SYSTEM AND ITS DISTRIBUTION
Authors: LIU YOU-CHANG  ,   北京航空学院
Published: November 2020

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 gravitational field produced by the source matter no longer possesses gravitational mass, then the value of n in that expression can be determined, and the distribution of field energy can also be determined consequently.
PROFILES OF JUNCTION CURRENT AND CARRIER-CONCEN-TRATION IN GaAs INJECTION LASERS WITH FILAMENT
Authors: GU SHI-JIE  , HUO CHONG-RU  ,   中国科学院物理研究所
Published: November 2020

The profiles of junction current and voltage and carrier-concentration in an injection laser with filament were calculated on the basis of a simple model. Numerical results indicate how the various parameters such as bulk resistivity and carrier diffusion length in the active region affect the profiles. Particularly, the filament width is strongly dependent on the bulk resistivity. The model connects the stimulated radiation characteristics of the device with the measurable quantities of the external circuit. It shows that there is obvious difference between average density of operating current and current density in the filament rigion. It shows also that nonuniformity of material will play an important role in locating the filament.
THE SHELL MODEL FOR CLAD PARTICLES OF SUPERCONDUCTORS
Authors: ZHAO ZHONG-XIAN  , LIU FU-SUI  , HAN RU-SHAN  ,   (1)北京大学物理系; (2)中国科学院物理研究所
Published: November 2020

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 clad particles with different sizes by the Louie and Cohen's critical temperature Tc fomula which is valid to both weak and strong coupling superconductors. The calcutated results are in agreement with experimental data which have been published so far. In contrast to other authors' calculated results, our results give conclusion which shows that the Tc of Pb clad particles decreases when the size of the particles is reduced.
THE ELECTRO-OPTIC,PYROELECTRIC,DIELECTRIC AND PIEZOELECTRIC PROPERTIES OF THE SINGLE CRYSTAL Sr4NaLiNb10O30
Authors: ZHU YONG  , ZHANG DAO-FAN  ,   中国科学院物理研究所
Published: November 2020

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 temperature. The depolarization is almost undetectable in the erystals poled previously. A pyroelectric device using this crystal has been made and its detectivity D is found to be no less than 1.7×107cm·Hz1/2/w. In addition, the dielectrie and some piezoelectric properties are described in this paper.
ELECTRO-OPTIC FREQUENCY SHIFT OF 10.6μm CO2 LASER LINE
Authors: FU EN-SHENG  , WANG YU-MIN  , CHENG ZHAO-GU  , DOU AI-RONG  ,   中国科学院上海光学精密机械研究所
Published: November 2020

This paper presents a scheme for electro-optic frequency shifting. In this scheme linearly polarized light of output from CO2 laser passes through a electro-optic modula-tor and retroaction-cycle laser amplifer, under the condition of no increased harmonic components exist, the convertion efficiency of the shifting can be raised greatly. This work suggests that electro-optic frequency shifting possesses potentiality of wide appli-cation. In the experiments on checking the effect of the frequency shifting, the experi-mental device is simplifed by auto-collmating round-trip of the light beam and space delaying the modulated signal. The frequency components of the frequency shifted light is analysed by using simple method of frequency beating.
THE CRYSTALLIZATION HABIT AND DEFECTS OF SYNTHETIC QUARTZ
Authors: ZHONG WEI-ZHUO  ,   中国科学院上海硅酸盐化学与工学研究所
Published: November 2020

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 habit, an outer to inner relation between the external and the internal structures of the synthetic quartz has been established. Moreover, a correlation between the crystallization habit of the trigonal trapezohedron and the crystal defects has been studied for various seed orientations, namely the Z-cut, Y-cut, X-cut and the cut which intersects the Z-axis at 55°. The results of the experimental investigations show that the defects of synthetic quartz, usually called "facet defects", arise mainly from the growth traces of the crystal faces of the trigonal trapezohedron, while in the X-cut and Y-cut crystals there are still pyramidal growth interface defects formed between the various crystal faces concerned.
RELAXATION BEHAVIORS OF THE LIGHT DIFFRACTION INTENSITY AND RELATED "FREEZING" EFFECT AT LOW TEMPERATURES OBSERVED IN α-LiIO3 SINGLE CRYSTALS UNDER THE ACTION OF AN ELECTROSTATIC FIELD
Authors: ZHAO SHI-FU  , GU BEN-YUAN  , ZHANG AN-DONG  , XU ZHENG-YI  ,   中国科学院物理研究所
Published: November 2020

On the basis of our earlier work, the relaxation behaviors of the light diffraction intensity induced by the distribution of space charge in a-LiIO3 single crystals under the action of an electrostatic field have been investigated by using a space filter. The empirical expressions of the relaxation process were obtained. It was found that the parameters involved change with the temperature and from specimen to specimen, as well as depend both on the magnitude and the relative direction of the polarity of the crystal and the electrostatic field applied. When the temperature is lowered below a certain value (≈-25℃), the enhancement diffraction intensity due to the applied field becomes not quite evident. When the electrostatic field is applied at a temperature higher than the "freezing" point and then the specimen is cooled to a temperature below the latter, the magnitude of diffraction intensity enhanced by the applied voltage at higher temperatures remains unchanged, it is so even after removing the voltage. This "freezing" effect is parallel to that observed in the enhancement of neutron diffraction intensity.
THE BLOCKING EFFECT OF Si, GaAs AND LiNbO3 SINGLE CRYSTALS
Authors: CHEN CHANG  , WEI CHENG-LIAN  , DONG YU-LAIN  , LIU SHI-JIE  , XIA GUANG-CHANG  , FAN JING-YUN  , WANG QI-LIANG  , GAO ZHI-WEI  ,   中国科学院高能物理研究所
Published: November 2020

By making use of the back scattering method Si, GaAs and LiNbO3 Single Crystal blocking patterns were obtained and GaAs single crystal {110}, {100} and {112} plane blocking halfangle ψ1/2 values were estimated. We have found that the depth of the {110} plane blocking dip of Si slice damaged due to ion implanting becomes shallow when implantation dose increases. In order to check the experimental apparatus and the method, we have also obtained Si single crystal blocking pattern and measured the values of Si single crystal {110}, {111} and {100} crystal plane blocking halfangles
A DISCUSSION ON THE GENERALIZED LINEAR COHERENT OPTICAL-PROCESSING SYSTEM
Authors: ZHAN DA-SAN  ,   中国科学院物理研究所
Published: November 2020

In this article, we discuss the properties of the generalized linear coherent optical-processing system proposed in [1] and [2], and show that the equivalent system exists. We further show that the parameter Z1 is of little importance.
ON THE CORRELATION BETWEEN GROWTH FORMS AND INTERFACE MOLECULAR GROUP WAVINESS OF SYNTHETIC QUARTZ
Authors: ZHANG YUAN-LONG  ,   中国科学院上海硅酸盐化学与工学研究所
Published: November 2020

By using the seed crystals of designed profiles so that inward as well as outward growth may take place with respect to the z axis, various growth forms of synthetic quartz are displayed. The formations of three different types of trigonal tripezohedron, i.e. the vicinal of 5161, 6155 and the closed pair of triangular facets deformed from 2112 and 10559 are described. Direct evidences are given, demonstrating that during the lateral progression across z (0001) plane, the-x direction will overtake that of + x.The general sequence of growth rate of different faces including + x≥ - x is explained in terms of the duly proposed concept of interface molecular group waviness. In addition to the acuity of the molecular reentrant angles upon z(0001), the more widely opened and therefore more readily fitted lateral reentrant angles formed during the lateral movement of the growth front along the negative polar directions enhances the rate of progression.The reentrant angles of the growing molecules, projected on certain chosen reference axial plane, will act as a measure of the interface molecular group waviness. A hybrid series of interface types are classified, in which the degree of flatness of the molecular group waviness will determine the degree of "flatness" of the interface, while the share of "stepness" and "kinkness" is estimated by resolving the normal of the oriented interface into the directions of the diad and triad axes of the crystal respectively.The assumed statistically dominant form of the molecules in the supersaturated hydrothermal solution is ring shaped Si6O6(OH)12 with the least specific surface free energy, being a relatively more stable metastable stage, appear to be the more appropriate growth units. In accordance with the structure of the crystal and the orientation of the growing interface, the growing molecules will be oriented to adopt the maximum possible molecular reentrant angles so as to minimise the interfacial free energy. This basic assumption explains why growth on the prism faces is likely to be very slow.The polarization of molecules and adsorption of foreign ions on the growing polar faces and also the possible grouping of the ring shaped molecules before crystallization are finally discussed.
AN EMPIRICAL RULE FOR SUPERCONDUCTING A-15 TYPE COMPOUNDS
Authors: LUO QI-GUANG  ,   中国科学院物理研究所
Published: November 2020

A diagram which not only considers the transition of the structural type hut also describes the rule of change of Tc in the A-15 compounds is given in this paper. From this diagram it can be seen that compounds with very high Tc(>25K) are not likely to exist in the A-15 series considered. In the Nb series, Nb3Ge probably has the highest Tc; in V series, the Tc can still be expected to be raised (>17.1K), the Tc of V3Ge is likely to be raised to above 12 K. Examining the case of Nb3Si, one can not get the optimistic estimation as that of Geller. It is considered that Nb3Si of A-15 type obtained by present new technology is a non-ideal structure formed at the expense of the normal stoichiometric ratio or by a change of the ordinary atomic volume. On the basis of the relationship between Tc and radii ratio and on consideration of the radii ratio required by the ideal A-15 structure, the point of view presented in this paper does not agree with the various predictions that the Nb3Si might have a high Tc(>23 K).
THE CURRENT STEPS IN SUPERCONDUCTING WEAKLINKS
Authors: YAO XI-XIAN  ,   南京大学物理系
Published: November 2020

In the presence of a battery source and a radiation field, a superconducting weaklink can be represented by a simplified model consisting of a resistance shunted Josephson junction driven by a constant current source. Using such a model, we give a general criterion for the occuring of constant voltage current steps in the current-voltage characteristics of the weaklink. Following this criterion, we have also discussed the absence of sub-harmonic current steps. For the case while the radiation field is very weak, the current step heights are calculated by pertubation method. The current step heights are also obtained by numerical compution for the case of strong field.
AN APPROXIMATE HAMILTONIAN OF SUPERCONDUCTOR TUNNELING SYSTEM TREATED BY VARIATIONAL METHOD
Authors: WANG ZHENG-XING  ,   北京大学技术物理系
Published: November 2020

The variational approximation method developed by Bogolyubov et al. is generalized to treat the dynamical problems of superconductor tunneling system, which results in establishing the approximate expressions, in second quantization representation, for the equation of motion, the. Hamiltonian of superconductor tunneling system and the operators of tunneling current in this variational approximation scheme. The Hamil-tonian obtained, H = HL + HR + HT + WT, consists of three parts: HL describes the behaviours of the metal on the left hand side of the sample; while HR the behaviours of the metal on the right hand side; and HT+WT the coupling between them. HL and HR are commutable with each other, and their expressions are the same as two isolating metals, except that the states of single electron are slightly mixed. The formula of matrix elements of HT is identical with that of Bardeen. The effect of WT is approxi-mately 10000 times less than that of HT, hence WT may be neglected. It is demonstra-ted that as far as the first order terms in our variational approximation method is con-cerned, the model Hamiltonian assumed by Cohen et al. applies, while Prange's treat-ment for this problem is proved to be inappropriate.
THE SPECTRUM OF NIII IN THE VACUUM ULTRAVIOLET REGION
Authors: WANG WEN-SHU  , CHAO JIN-SEN  , TAO SHI-YAO  ,   中国科学院物理研究所
Published: November 2020

The spectrum of NIII has been studied in the region of 2000-680? by using a two meter normal incidence vacuum spectrograph and a condensed discharge as light source. Experimental results indicate the evident effect of the pressure of light source on the appearance of NIII spectral lines. Thirty-one new spectral lines are observed. A new energy level, 2s2p4d2D5/2, is found, and the energy value of the level 2s2p4d2D3/2 is revised.
REDUCED HUGONIOT CURVE AND EQUATION OF STATE OF METALS UNDER HIGH-PRESSURES
Authors: GAO WEN-BIN  ,   中国科学院安徽光学精密机械研究所
Published: November 2020

In this article, through summarizing experimental data of shock-wave compression for thirty-four metallic elements, we have obtained a generally applicable empirical expression for the reduced Hugoniot curve, which describes the law of shock-wave compressions for metallic elements. In treating these data, the principle of corresponding state was employed. By utilizing the obtained reduced Hugoniot curve and basing on the Debye theory, we have derived a generally applicable equation of state for metallic elements under high pressures. We used this equation of state to calculate the pressure-compression curves for fifteen metallic elements (magnesium, iron, copper, etc). The comparison shows that the calculated values are in good agreement with experimental data.
GROWTH AND CHARACTERISTICS OF LITHIUM NIOBATE PLATE CRYSTALS
Authors: ULTRASONIC PIEZOELECTRIC MATERIALS GROUP  ,   中国科学院声学研究所
Published: November 2020

Growth of lithium niobate large plate crystals was achieved by using the Wet-ted-Die Technique. Their dimensions were about 200 mm long, 20 mm in width and 3 mm thick. Their properties was found to be the same as those of cylindrical crystals. We measured the density ρm of the melt of lithium niobate and its surface tension a. The results are: ρm= 3.57×103kg/m3, α = 204 dyne/cm at 1270℃, and ρm= 3.42×103kg/m3, α = 192 dyne/cm at 1300℃.
A THEORETICAL MODEL FOR TRANSVERSE-DISCHARGE FLOW TYPE CO2 LASERS
Authors: GAO ZHI  , LIN LIE  , SUN WEN-CHAO  ,   中国科学院力学研究所
Published: November 2020

A theoretical model is proposed to analyse the transverse-discharge flow type CO2 lasers. Theoretical expressions are obtained for predicting gain-saturation and output power of flow type gas lasers, these expressions are in agreement with the well-known formulae of non-flowing gas lasers, but the former contains correction terms related to pumping action in the upstream direction of the cavity and the gas flowing effect. Based on the analysis of the variation of intensity in the direction of flow, we derive the limiting values of stauration intensity and other parameters which were attained as the flow speed was being increased. Reliability of the semi-empirical analysis suggested, in literature [1-3] for the flow type laser performance predicted by choosing an average gain-coefficient anl adopting the formulae of non-flowing gas lasers has been proved. The qualitative analysis presented in article [4] is developed into a quantitative calculation. The present model should be used in place of the semi-empirical one, since the formulae deduced are as simple as those for the non-flowing gas lasers. The results computed for both amplifier and oscillator cavities using the present model are in agreement with experimental data [1, 18-21].
MHD EQUILIBRIUM AND STABILITY OF AXIAL SYMMETRIC TOROIDAL PLASMA WITH AN ELLIPTIC CROSS SECTION OF TRIANGULAR DEFORMATION
Authors: MA TENG-CAI
Published: November 2020

Expanding the magnetic flux in terms of the deviation from the magnetic axis, we have studied the MHD equilibrium and localized mode instability of an axial symmetric plasma torus with a small triangular and elliptical deformation on its cross-section. The optimization of the configuration has been analyzed and an optimal factor of the triangular deformation has been given. Our analysis shows that it is possible to strengthen ohmic heating substantially by selecting suitable factors of the triangular deformation.
A GENERAL TRANSFORMATION FORMULA FOR SHG COEFFI-C1ENTS OF A CRYSTAL AND THOSE OF ITS ANIONIC GROUPINGS
Authors: CHEN CHUANG-TIAN  , CHEN XIAO-SHEN  ,   中国科学院福建物质结构研究所
Published: November 2020

By using the irreducible tensor method of representing SHG coefficients, we have proposed in this paper a general transformation formula for SHG coefficients of the macroscopic crystal and those of its microscopic anionic groupings. It thus leads to a series of calculation formulas suitable generally for calculating the contributions of the anionic groupings of different orientations in the crystal to the macroscopic SHG coefficients. It has been shown that this method can be used conveniently to calculate the SHG coefficients of various iodates. The agreements of our calculation values with the experimental ones are quite satisfactory. Our work has provided a dear stero-structural criterion for searching of new types of SHG materials.
INVESTIGATION OF THE SOLID SOLUTIONS IN ALKALI- METAL IODATE PSEUDO-BINARY SYSTEMS
Authors: TANG DI-SHENG  , CHE GUANG-CAN  , TIAN JING-HUA  ,   中国科学院物理研究所
Published: November 2020

Among the 21 pseudo-binary systems formed by alkali-metal iodates (including HIO3 and NH4IO3), there are 9 in which compounds can be synthesized in aqueous solutions or by powder-sintering, 6 which are mixtures of the constituents; and the rest of the systems can formed continuous solid solutions. The pseudo-binary systems KIO3-NHJO3, RbIO3 etc. were studied by means of thermal analysis (DTA, TG) and Xray diffraction, and were found to be of continuous solid solutions. With addtion of KIO3 or RbIO3, the phase transition temperature of NH4IO3 is decreased and its decomposition (at the same time burning) temperature is raised; the room temperature phase of NH4IO3 (monoclinic) is transformed gradually into cubic phase with increasing content of KIO3 or RbIO3. Samples in the binary systems with NH4IO3 as a component exhibit good pyroelectric property. In this paper, the stability and the change of lattice parameter with compositions of the solid solutions that were found in alkalimetal iodate binary systems were also discussed.
CRYSTAL GROWTH, MORPHOLOGY AND OPTICAL PROPERTY OF COMPLEX SALT KIO3 2LiIO3
Authors: HU BO-QING  , MA WEN-YI  , ZHOU TANG  ,   中国科学院物理研究所
Published: November 2020

The growth condition of the complex crystal KIO3·LiIO3 and its infrared spectra have been investigated. The morphology of the crystal has been determined. Its class is 2/m. The parameters of its cell are a = 11.189, b = 11.038, c = 8.262, β = 111°27′. The position of the optical indicatoid for the crystal, the refraction indices in the range of visible light and their Sellmeier's equations have been given.
CRITERION OF PRIMITIVE SOLUTIONS IN THE AUTOMATIC INDEXING OF ELECTRON DIFFRACTION PATTERNS
Authors: GOU KE-XIN  , LIU PING  ,   中国科学院金属研究所
Published: November 2020

Electron diffraction patterns can be automatically indexed by comparing two nearest diffraction spots with two calculated reciprocal vectors r1* and r2*2, r1*×r2*= Au. However, non-primitive solutions corresponding to non-primitive reciprocal plane cells, sometimes result. For simple Bravais lattices, obviously A=1 is the criterion of primitive solutions. For primitive solutions in centred Bravais lattices, it has been shown that A has also specified values for various combinations of u, v, w indices.
ON THE FACETS AND TWIN FORMATION IN THE GROWTH OF InSb SINGLE CRYSTALS
Authors: YU ZHEN-ZHONG  , JIN GANG  , CHEN XIN-QIANG  , MA KE-JUN
Published: November 2020

The observations of solid-liquid interface morphology of InSb single crystals pulled by using various oriented seeds is described. Experimental results indicate that the external forms of crystals as well as the formation of growth twin are closely related to the development and properties of {111} facets on the solid growth surface. The various experimental phenomena can all be interpreted successfully according to a {111} plane octahedron or two-octahedron model of the zinc-blende structure.
THEORY OF OPTIMUM DESIGNING FOR THE SYSTEMS OF PULSE STRONG MAGNETIC FIELD
Authors: ZHANG YU-HENG  ,   中国科学技术大学物理系
Published: November 2020

After a comprehensive consideration on the factors of coil, circuit, and power, this article gives, for the first time, a general theory of designing a standard capacitor discharge pulse magnet (winding coil, Bitter coil, or single turn coil).According to the theory, the optimum contruction parameters of the magnet and the parameters of the power (i0, F(α, β), a2, b, L, C, N, l, S, (or d), B, and Imax) can be caculated if only the figures of B0, 2a, 1/2 T, λ,σ, and v are given.This article also makes a physical study on the optimum construction of magnet.
A STUDY OF THIN FILM GRATING COUPLER
Authors: XU DE-WEI  ,   中国科学院长春物理研究所
Published: November 2020

A grating coupler with a period of 0.56 μm has been built on the glass substrate by duplicating technique from a master grating. It has been experimentally observed that laser beam can be coupled into the waveguide film from above cair, as well as from below (substrate). The mode excited in the waveguide can be varied by varying the angle of incidence of laser beam, and light wave of different diffraction order can also be coupled into guide wave mode. An input coupling efficiency of 66.0±0.5% has been achieved experimentally.
THE TOTAL YIELD AND ENERGY SPECTRA OF THE SECON-DARY PARTICLES OF THERMONUCLEAR REACTION
Authors: XU JIN-KUI  ,   中国科学院原子能研究所
Published: November 2020

Starting from the basic formulism of nuclear reaction kinematics, the general expressions of the total yield and the energy spectra of the secondary particles of thermonuclear reactions in plasma with the Maxwellian velocity distribution of ions have been derived. The possibility of using the neutron and charged particles as a tool of plasma diagnostic is also discussed.
A DISLOCATION SOURCE IN THE FLOAT-ZONE GROWN SILICON SINGLE CRYSTALS
Authors: LIU ZHEN-MAO  , WANG GUI-HUA  ,   哈尔滨工业大学
Published: November 2020

The impurity-striations and the dislocation loop series produced from the volume indentation by these impurity-striations in the float-zone grown silicon single crystals have been studied by means of chemical etching method. The experimental results have shown that the impurity-striations are oriented in the direction (110) of planes {111} in silicon, the length of the impurity-strialions is about 5-230μm, the dimensions on cross-section are about 2-3 pun. The geometrical structure of the dislocation loop series produced by volume indentation of the impurity-striation has been studied. The form and size of a single dislocation loop depend on the form and size of the impurity-striation. The dislocation networks resulting from the cross-superposition of the dislocation loop series and reactions between these dislocation loops have been observed and analyzed.
DISLOCATION INTERNAL FRICTION PEAKS WITH ANOR- MALOUS AMPLITUDE EFFECT IN Al-Mg ALLOY
Authors: PAN ZHENG-LIANG  , WANG ZHONG-GUANG  , KONG QING-HU  , GE TING-SUI  ,   中国科学院金属研究所
Published: November 2020

Two low frequency internal friction peaks have been observed at 243 K and 333 K respectively in Al-0.03 at% Mg alloy during the process of temperature going up after the specimen was stretched in situ with a tensile strain of 0.5% at 208 K. Such two peaks appeared also at the same temperatures when the measurement was made in the subsequent cooling from 353 K. The dependence of internal friction on the amplitude was determined and the amplitude internal friction peaks were observed in the temperature range of the peaks. The relationship between these two kinds of peaks was analysed and the effective activation energies of the temperature internal friction peaks were found to be about 0.32 eV for the 243 K peak and 0.22 eV for the 333 K peak. It was suggested that the two peaks at 333 K and 243 K may be respectively associated with the dragging of the solute atoms and the "Mg atom-vacancy" pairs, which may be produced through the sidewise motion of the kinks on the dislocations formed during the low temperature cold working.
RANDOM SYSTEMS WITH INHOMOGENEOUS CONCENTRATION
Authors: ZHANG ZHAO-QING  ,   中国科学院物理研究所
Published: November 2020

The methods of configurational average of ensemble on a homogeneously random binary system is extended to treat a conditionally random binary system, where the concentration of one species c(r) is not a constant but modulated in a certain way. A restricted ensemble is chosen to describe such a system, the corresponding generalized CPA equation is derived. If we separate c(r) into c and δc(r), a decomposition scheme is introduced to average the uniform part c and deviation part dc successively. For a sinusoidal modulation, the averaged single-particle Green's function and its self-energy are calculated formally to the second order in δc/c. In the virtual crystal limit, the band splitting character of a superlattice is recovered.
A PRELIMINARY STUDY ON THE RELAXATION OF Si(111) SURFACE ATOMS
Authors: ZHANG KAI-MING  , YE LING  ,   复旦大学现代物理研究所
Published: November 2020

In this paper the Extended Hucker Method is adopted and the Cluster model is used to calculated the surface relaxation of the Si (111) plane. The calculation shows that the surface atoms will be displaced inward with respect to their "ideal" positions by an amount of 0.10?. This expectation is in better agreement with the experimental results than previous empirical evaluations and theoretical calculations.
SUPERCONDUCTING CRITICAL FIELDS OF TYPE A AND TYPE B SUPERCONDUCTORS
Authors: ZHANG YU-HENG  , CAO XIAO-WEN  ,   (1)中国科学技术大学; (2)中国科学院等离子体物理研究所
Published: November 2020

In this paper, the experimental data of thermodynamical critical magnetic field Hc at T = OK are analysed. The conclusion arrived here is that Hc(O) is increasing with λ for type A, and with λ2> for type B superconductors.
ANOMOLOUS PATTERNS OF TUNGSTEN SAMPLES OBSERVED WITH SCANNING ELECTRON MICROSCOPE
Authors: LIAO QIAN-CHU  , WANG YUN  , WANG HONG-JUN  , LAN FEN-LAN  ,   北京钢铁研究院
Published: November 2020

On recording a number of SACP's of tungsten specimen successively tilted -to different orientations, some anomolous patterns superimposed on the general SACP's were observed at the exact positions of direction, direction, and direction. These anomolous patterns are similar to Kossel patterns observed with transmission electron microscope. Moreover, the present patterns have two additional important characteristics. First, the intensity distribution of patterns changes with the electron energy (the electron accelerating voltage). Second, the geometric feature of the patterns can be used to represent some characters of the internal structure of the crystal. Finally, from the view points of the anomolous scattering effect, and the parameter a, which represents the interaction strength between the crystal potential. and the incident electron, the origin of the contrast of these patterns was explained qualitatively.
THE STOCHASTIC MODELS FOR NON-EQUILIBRIUM SYSTEMS AND FORMULATION OF MASTER EQUATIONS
Authors: YAN SHI-JIAN  , LI ZHAN-BING  ,   (1)北京师范大学量子力学小组; (2)北京师范大学数学系
Published: November 2020

In this paper we present clearly a set of postulates on probabilities which are the basis of the nonlinear master equations and multivariate linear master equations appeared in non-equilibibrium statistical physics. By using the methods of probability theory, we deduced these master equations from our general postulates. We further discussed the conditions under which the master equations are consistent with the macroscopic kinetic equations. Finally, we discussed the fluctuation in Brusselator model using multivariate linear master equation approach and made a preliminary explanation on the appearance of dissipative structure through fluctuation.
ELECTRON DIFFRACTION INVESTIGATION OF AMORPHOUS Gd-Co ALLOY FILMS
Authors: LI FANG-HUA  , WANG YIN-JUN  , GAO JUN-JIE  , TENG CHEN-MING  , CHANG LONG-CUN  ,   (1)天津大学,进修教师; (2)中国科学院物理研究所
Published: November 2020

Electron diffraction technique was used to study the structure of various amorphous films of Gd-Co alloy and Lorentz electron microscopy was used to observe the related magnetic structure. Seven halos could be seen clearly in all the electron diffraction patterns obtained and the two smallest halos were located in the range s-1 (s = (2sinθ)/λ). Magnetic bubbles or in-plane domain structures wereobserved in these amorphous films. For amorphous alloys of this type consisting of two elements, such as rare-earth and transition metals with a large difference in atomic radius, we showed how to derive directly and qualitatively the relative co-ordination number of nearest neighbours between rare-earth metal atoms, - between transition metal atoms, and between rare-earth and transition metal atoms, merely from the diffraction intensity profiles in the range s-1. The influence of phase separation in the film on the magnetic anisotropy was also discussed.
FORMATION OF HARD BUBBLES UNDER BIAS PULSE FIELD
Authors: LIU YING-LIE  , NIE XIANG-FU  , HAN BAO-SHAN  ,   (1)河北师范大学物理系; (2)中国科学院物理研究所
Published: November 2020

The conditions under which hard bubbles form in the process of gererating bubbles by a low frequency pulse field were experimentally studied. It was found that the percentage P of hard bubbles decreases quickly with increasing amplitude Hp of the bias pulse field. There was evidence for the existence of a critical value Hpo, such that when Hp≥Hpo, all bubbles generated were soft ones.
DETERMINATION OF X-RAY POWDER DIFFRACTION DATA FOR SODIUM STRONTIUM BARIUM NIOBATE SYSTEM
Authors: GUO CHANG-LIN  ,   中国科学院上海硅酸盐研究所
Published: November 2020

The X-ray powder diffraction patterns of various compounds of sodium strontium barium niobate system were obtained with a counter diffractometer and a Guinier focusing camera using CuKα radiation. The detail indexed powder diffraction data for Ba2NaNb5O15, SrBaNaNb5O15 and Sr2.05Na0.90Nb5O15 were given. These data may replace those presented in the JCPDS X-Ray Powder Diffraction Standards Data Pile (Cards No. 23-654, 27-1408, 27-1409, 27-787).
AN INVESTIGATION OF DIVALENT IODATES AND THEIR COMPLEX SALTS
Authors: LIANG JING-KUI  , YU YU-DE  , DING SHI-LING  ,   (1)中国科学院物理研究所; (2)中国科学院物理研究所,中国科学技术大学
Published: November 2020

The phase transitions, thermal stabilities and crystal structures of strontium iodate, barium iodate, calcium iodate, zinc iodate and cadmium iodate have been investigated by means of X-ray powder diffraction and thermal analyses. The possibilities of formation of complex compound between divalent iodates have been studied. The stability of hydrated divalent iodates is expected to be related to the electronegativity of the corresponding cations.
THEORY OF HIGHER ORDER CHROMATIC ABERRATIONS
Authors: LIN DA-JIAN  , XUE MING-QIU  ,   (1)中国科学院长春光学精密机械研究所; (2)中国科学院光电技术研究所
Published: November 2020

In this article, we discuss the changes of the coordinates of the pupil and the object plane caused by the Seidel aberrations of the front groups in the optical system, and also the effect of these changes on the chromatic aberrations of the back groups, i.e., the theory of derivative higher order chromatic aberrations.
ON THE UNIFORMITY OF THE ILLUMINATION-DISTRIBUTION ON THE WINDOW OF AN INTEGRATING SPHERE
Authors: LI YA-JUN  ,   浙江大学光学仪器系
Published: November 2020

In this paper we analyzed the uniformity of the illumination-distribution on the window of an integrating sphere and obtained the distribution function determined by the geometrical parameters of the sphere. On the basis of this result, we discussed the condition of existence of the equi-illumination circle and also such problems as the calculation of the blind region.
QUANTITATIVE DETERMINATION OF SPECTRAL PURITY OF X-RAY TUBES FOR DIFFRACTION ANALYSIS
Authors: GUO CHANG-LIN  ,   中国科学院上海硅酸盐化学与工学研究所
Published: November 2020

In this paper, a method for quantitative determination of spectral purity of X-ray tubes for diffraction analysis is presented. The instrument used for this purpose was a home-made diffractormeter with a monochrometer of quartz crystal plate which is used as the analyzer. The experimental values of the X-ray intensities of various wavelengths must be expressed in terms of intensities just emitted from the X-ray tube window. Theoretical analysis of the various factors affecting intensity was made in detail, and the conversion factors for the reduction of intensities corresponding to different target elements and impurities was summarized in a table. The intensity of major characteristic spectrum line of the target element was attenuated by Cu or Al absorption foils, so as to avoide the errors caused by counting loss. Using this method, the spectral purity of a number of X-ray tubes was determined.
A COMMENT ON THE COMPOSITE QUANTIZED FIELD THEORY AND BOUND STATES
Authors: WANG RONG  ,   中国科学技术大学研究生院
Published: November 2020

The interrelation between traditional quantum field theory and composite quantized field theory is investigated. It is found that they are compatible and interrelated in the ladder approximation, whereas beyond this approximation the interrelation is not established.
X-RAY DIFFRACTION TOPOGRAPHIC STUDY OF CRYSTAL DEFECT IN LiNbO3
Authors: ZHOU HENG-NAN  , JIANG SHU-SHENG  ,   南京大学物理系
Published: November 2020

Various kinds of crystal defects, such as ferroelectric domain boundaries, growth bands, dislocations, subgrain boundaries and cellular structures, etc. in Czochraski-grown ferroelectric LiNbO3 single crystals were investigated by X-ray transmission topographic technique. The defects were identified by means of invisibility conditions using different diffractions, as well as X-ray anomalous scattering effect and optical microscopy. We have discussed the formation of domain boundaries in LiNbO3 and their relation to the growth bands.
A REVISION ON RENSCH'S FINITE DIFFERENCE METHOD FOR CALCULATING THE FIELD DISTRIBUTION IN RESONATORS
Authors: WU ZHONG-XIANG  ,   中国科学院力学研究所
Published: November 2020

The field distribution in Gerry's GDL device was calculated with a revised Een-sch's finite difference method. The results agreed quite well with Rensch's calculation. This revised method was applied in a wider range of coupling. Thus the question, why the power output from a unstable cavity is the half of that from a stable one, can be explained more exactly by the fact that the coupling used was too large as compared with the optimum value.
DIELECTRIC AND PYROELETRIC PROPERTIES OF SINGLE CRYSTAL TGS GROWN BY THE METHOD OF CHANGING SOLVENT
Authors: DENG ZHAO-DE  , SHAO SHI-PING  , LIANG HONG-LIN
Published: November 2020

TGS single crystals can be grown by the method of changing solvent, i.e., adding ethyl alcohol to the aqueous solution of TGS. Ferroelectric hysteresis loop, as well as dielectric and pyroelectric properties have been measured. It is found that the properties of TGS grown by this method are similar to that grown by slowly lowering the temperature at constant supersaturation.
RADIATION DENSITY IN LASER CAVITY CALCULATED BY FIELD STRENGTH SUPERPOSITION
Authors: WU ZHONG-XIANG  ,   中国科学院力学研究所
Published: November 2020

On principle, the coherent light intensity in a laser cavity should be calculated according to field strength superposition of the light waves propagating back and forth in the cavity. This paper compares the calculations using the field strength superposition and that using the usual light intensity superposition. Our work indicates that the results on local saturated gain and light intensity calculations really give considerable discrepancies, but the field distribution and power output calculations agree quite well.
ELECTRONIC IMPACT EXCITATION OF LITHIUM-LIKE IONS
Authors: LI JIA-MING  ,   中国科学院物理研究所
Published: November 2020

We propose here a simple theoretical method to calculate excitation cross sections for electron-ion collision processes. At low energies, we apply the Multichannel Quantum Defect Theory to calculate excitation cross sections based on accurate data of energy levels which have been deduced from extensive spectroscopic measurements. At high energies, we then calculate cross sections based on Bethe Theory. At intermediate energies, we can apply interpolations to calculate mean cross sections if we smooth out local resonance structures. Reliable data for electronic impact excitations of ions are useful in the controlled thermalnuclear reaction researches. As an example, we calculate the (2S-2P) excitation for lithium-like ions to illustrate our proposed theoretical method.
CONTINUOUSLY TURNABLE LASER FROM INFRARED TO X-RAY REGION BY USING THE RELATIVISTIC DOPPLER EFFECT OF HIGH ENERGY ION BEAM IN NEGATIVE TEMPERATURE STATE
Authors: LI FU-LI  ,   中国科学技术大学
Published: November 2020

It is shown that a laser by using the relativistic Doppler effects of high energy ion beam in negative temperature state will be continuously turnable from infrared to X-ray region. The turnability range is △νT=2ν0βγ. The relativistic fransform of the laser parameters are given, and the gain, threshold" and output parameters of the relativistic ion beam laser are calculated in the present work. The methods to excite ion beam by means of laser are analysed. The design of He+ and Ar+ ion beam lasers are also discussed.
A SIX-BEAM HIGH POWER NEODYMIUM GLASS LASER
Authors: XU ZHI-ZHAN  , LI-AN-MING  , CHEN SHI-SHEN  , LIN LI-HUANG  , LIANG XIANG-CHUN  , OUYANG BIN  , YIN GUANG-YU  , HOU XING-FA  ,   中国科学院上海光学精密机械研究所
Published: November 2020

This paper describes the outline, the technical details and the output beam characteristics of a six-beam high-power Nd glass laser system used to irradiate [(CD2)n] spherical targets. The laser pulse width can be varied from 1 ns to 4 ns. If the pulse length is 2ns, the output energy of each of the six-beams is approximately 50 J, the beam divergence being 0.4 mrad and the total output power of all these beams approaching approximately 1.5 × 1011 watts.
ENHANCED PLASMA-FREQUENCY RADIATION IN TOKAMAKS
Authors: WU C. S.  , ZHOU RU-LING  , KANG SHOU-WAN  , XIA MENG-FEN  , CAI SHI-DONG  ,   (1)北京大学物理系; (2)美国马里兰大学; (3)中国科学院物理研究所
Published: November 2020

This paper is concerned with the phenomenon of enhanced plasma-frequency radiation in Tokamaks which has attracted much attention recently. Experimental results indicate that the radiation is associated with high energy runaway electrons. However the emission mechanism has not been completely understood. In this paper we review and discuss two possible processes which can explain the observed enhanced radiation. One is an induced emission process which is due to an anomalous cyclotron resonance of the runaway electrons with waves. The other is a spontaneous radiation process mainly due to Cherenkov resonance. The former requires higher energies of the runaway electrons than that required in the latter. Thus the theory of the spontaneous emission is more appealing and deserve more attention. Extensive numerical calculations of the emissivity have been performed over a broad range of parameters. The discussion is also extended to the case in which the electron plasma frequency is higher than the cyclotron frequency, a situation may be reached by Alcator.
A X-RAY INVESTIGATION OF THE MANGANESE-GALLIUM SYSTEM
Authors: LU XUE-SHAN  , LIANG JING-KUI  , SHI TING-JUN  , ZHOU MIN-QIANG  ,   (1)中国科学院物理研究所; (2)中国科学院物理研究所,中国科学院上海硅酸盐研究所
Published: November 2020

Debye-Scherrer photographs have been taken from forty-four slowly cooled and quenched manganese-gallium alloys. These, incorporated with the differential thermal analysis taken at the gallium-rich side, provide a basis for the Mn-Ga constitutional diagram.There are ten different phases beside pure Ga in the entire system. The solid solubility of Mn in Ga is almost undetectable. The α phase is the primary solid solution of Ga in α-Mn. The solubility limit at room temperature is 1.95 at % Ga. The β phase has a homogeneity range from 8.6 to 19.2 at % Ga at room temperature. The structure is that of β-Mn. It may be looked upon as a solid solution of Ga in β-Mn, stabilized at room temperature due to the random substitution of some of the Mn atoms by Ga. The γ phase may be divided into three parts, γ1, γ2, and γ3. γ1 is face-centred cubic, γ2, face-centred tetragonal, while γ3, face-centred tetragonal with a long range order. The structure of γ3 is isomorphous with CuAu I in the Cu-Au system. γ3 is stable at room temperature, the homogeneity range being from 37 to 45 at% Ga; while γ1 is only stable at high temperatures. The transformations from γ1 to γ2 and then to γ3 are of the second degree, the degree of order increasing with the Ga content and decreasing with the temperature. The whole phase γ may be considered as a solid solution of Ga in γ-Mn, which could not be retained by quenching in the pure state. The δ phase exists only at high temperatures. It may be regarded as a solid solution of Ga in δ-Mn, deformed and ordered by the substitution of some of the Mn atoms by Ga. The ε phase has an ordered hexagonal close-packed structure with eight atoms per unit cell. It is formed congruently from the y phase at about 820℃. The homogeneity range at room temperature is estimated to be from 27 to 30 at% Ga. The η phase has a wide range at room temperature, estimated to be from 50 to 60 at% Ga. From 520 to 600℃, it undergoes a polymorphic transformation to another phase λ, the homogeneity range of which being displaced with temperature toward the Mn-rich side. Both η and λ indicate quite complicated structures. At the Ga-rich side, there are three intermediate phases x, φ and ω. They are formed by peritectoid or peritectic reactions. The ideal structure of φ is cubic of the NiHg4 type, but it lies outside of the very narrow homogeneity range around Mn2.3 Gay7.7. Most probably the stoichiometric composition of the ω phase is Mn2Ga9 or MnGa5. Among the six intermediate phases stable at room temperature, β, ε, γ3, x and φ are ferromagnetic. The most pronounced ferromagnetic alloys have been found in the γ3 and φ regions which are rich in Ga content. Saturation magnetizations and Curie points for some of the alloys have been determined.
THE TEMPERATURE DEPENDENCE OF THE FRANKEL EXCITON EFFECTIVE MASS
Authors: GU SHI-WEI  ,   内蒙古大学物理系
Published: November 2020

The properties of a Prankel exeiton in a polar crystal is discussed by means of a model which takes account of the atomicity of the lattice. The lattice vibration and the interaction of the exeiton with the lattice displacement is discussed by second quantization method. The temperature dependence of the effective mass of Frankel exeiton is derived.
SPECTRAL PROPERTIES OF Nd3+ IN GLASS
Authors: CHEN SHU-CHUN  , QI CHANG-HONG  , DAI FENG-MEI  ,   中国科学院上海光学精密机械研究所
Published: November 2020

This paper analyses stark splittings of Nd3+ in glasses. The experimental method of determining fluorescence levels is described and the experimental results of stark splittings of the metastable states and ground states for four types of Nd3+-doped silicate glasses are given. In addition, the radiative and non-radiative transition rate of the 4F3/2 state, the stimmulative emission cross-section σ, the radiative quntum efficiency η, the fluorescence branching ratio β and the lifetime τ are also determined experimentally for thirteen types of Nd-doped glasses with different compositions. On the basis of experimental results, the relation between non-radiative transition rate and compositions of the hosts is discussed.
CT-6 TOKAMAK RESEARCH (Ⅰ)——DEVELOPMENT AND TEST OPERATION OF THE EXPERIMENTAL DEVICE
Authors: GROUP 104  , GROUP 403  ,   (1)中国科学院电工研究所四○三组; (2)中国科学院物理研究所一○四组
Published: November 2020

Tokamak is an experimental fusion device in which hightemperature toroidal plasma is produced, it belongs to the category of complicated modern electro-physical facilities. CT-6 is the first small tokamak device in operation in our country, its main parameters are as follows: major radius R: 45cm; minor radius a: 9.2cm; toroidal magnetic field: 2TL; plasma current Ip: 30 kA. After careful test operation and adjustment design goal had been achieved and stable hot toroidal plasma with electron temperature about 250 eV was produced. CT-6 device consists of electro magnetic system (toroidal, Ohmic heating and equilibrium field systems), ultra-high vacuum system (toroidal vessel and pumping system), power supply and control system, diagnostic system. It is designed, developed and operated jointly by Institute of Physics and Institute of Electrical Engineering of Academia Sinica, in collaboration with many other institutions.In the present article the design, structure, engineering development, and also relevant results given by the test operation of CT-6 device are described.
A HIGH EFFICIENCY STIMULATED RAMAN SCATTERING SOURCE
Authors: WU CUN-KAI  , FAN JUN-YIN  , WANG ZHI-YING  ,   中国科学院上海光学精密机械研究所
Published: November 2020

This paper reports the experiment in which by using broadspeetrum 5314? laser beam as the pumping radiation, an intense 6296? stimulated Raman scattering stokes emission was achieved in the organic solution (CH3)2SO. With a intermediate power density, the efficiency of energy conversion to forward stimulated Raman scattering approached 38%. The backward Stokes stimulated emission was observed, and the backward wave intensity was about 80% of the forward scattering intensity. The gain of the forward scattering wave was measured and was about 2.5×10-3cm/ MW, the spatial distribution and the beam divergence of the forward and backward waves were measured. The improvement of the beam direction of the backward wave was demonstrated.