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Vol. 34, No. 2 (1985)

1985-01-20
CONTENT
INTERACTION EFFECTS IN DILUTE MAGNETIC ALLOYS
LI ZHENG-ZHONG, HU XIAO-XIN, WANG JIN-CAI
1985, 34 (2): 145-154. doi: 10.7498/aps.34.145
Abstract +
In this paper, the influence of interaction between magnetic impurity ions on the Kondo effect is treated by using Green's function method under the condition Tk (Kondo temperature). A self-consistent-field approximation for s-d exchange Hamil-tonian is adopted. Both of the two types of the decoupling terms, which are responsible for single-ion Kondo effect and inter-ionic interaction respectively, are retained. The Kondo temperature and the low-temperature resistivity for impurity system have been calculated. The results indicate that in dilute magnetic alloys interaction effects will decrease Tk and make the ρ-T curve in the region T《 Tk changes from 1-AT2 to 1 + BT2, with A,B > 0. Thus a resistivity maximum may probably be observed in the temperature region T k.
INFLUENCE OF CUBIC MAGNETOCRYSTALLINE ANISO-TROPY ON THE STABILITY OF STRIPE DOMAIN AND BUBBLES SUBJECTED TO AN IN-PLANE FIELD
NIE XIANG-FU, TANG GUI-DE, HAN BAO-SHAN, LI BO-ZANG
1985, 34 (2): 155-163. doi: 10.7498/aps.34.155
Abstract +
The erasing process of stripe domains in eight (111)-oriented garnet bubble films was observed in the presence of an in-plane field. The stripe domain erasing field H*s and the domain erasing field H*k were measured as functions of the azimuthal angle βof the in-plane field. Taking the cubic magnetocrystalline anisotropy into account, a theory of stability of stripe domains subjected to an in-plane field was developed. The main features of the experimental results can be expained qualitatively by this theory. Two theoretical relationships between Hs* and βas well as K1 were found. They are applicable to the cases that the direction of in-plane field is near and not fairly near the 〈110〉 crystallographic axes respectively, and are found to be roughly consistent with the experimental results. In particular, along the 〈110〉axes an analytical expression was obtained:Hk〈110〉* =Hs〈110〉*=Hk{1+ K1/2ku-[al/h(4pMs/Hk)2]2/3},which is in good agreement with the experiments.
THE TRANSITIONS OF Fe2+-Fe3+ PAIRS IN TOURMALINE
SHEN GUO-YIN, WAN KE-NIN, SHANG BO
1985, 34 (2): 164-170. doi: 10.7498/aps.34.164
Abstract +
Crystal field theory has been used to calculate the spin allowed transition of Fe2+ ions with 3d6 configuration in the two substitutional sites of interest in tourmaline, i. e., in b and c-sites which have Cs and C1 point group respectively, by using Zhao's SCP d-orbit of Fe2+ ion. The transition of Fe2+-Fe3+ ion pairs, (Fe2+[g]-Fe3+)→(Fe2+[e]-Fe3+) which has not previously been studied, is discussed here theoretically. An estimate of the magnitude of the intensity of the three strongly polarized (E⊥c>>E//c) bands near 9,000cm-1,13,800cm-1,15,000cm-1 in the near-infrared region is given. The interpretation of the near-infrared absorption spectra of tourmaline is satisfactory.
BASIC STUDY ON SPATIAL FILTER USED IN Nd-GLASS HIGH POWER LASER SYSTEM
WANG GUI-YING, ZHAO JIO-YIAN, ZHANG MING-KE, FAN DIAN-YIAN, GUI ZHAI-QUAN
1985, 34 (2): 171-181. doi: 10.7498/aps.34.171
Abstract +
In this paper, image relaying of the spatial filters on the high power Nd-Glass laser system for improving brightness of laser beam is demonstrated. Detailed theoretical treatment and numerical calculation on selection of filtering pinholes are carried out. Finally, a new idea about the depth of field of spatial filter and several new experimental methods of adjusting spatial filters are suggested.
OPTICAL SWITCHING AND BIST ABILITY IN A FABRY-PEROT INTERFEROMETER CONTAINING PLASMA
ZHONG QUAN-DE
1985, 34 (2): 182-187. doi: 10.7498/aps.34.182
Abstract +
In this paper, the optical switching and bistability of a Fabry-Perot interferometer filled with plasma are studied theoretically. In the plane-wave approximation a equilibrium state equation which shows nonlinear transmission-intensity characteristic is derived. The critical detuning and the general formulae of "on " and "off" intensities for bistable operation are presented. A numerical example is given.
STIMULATED BRILLOUIN SIDESCATTERING IN LASER-IRRADIATED PLASMAS
XU ZHI-ZHAN, LIN KANG-CHUN, QIAN AI-DI, ZHANG WEN-QI
1985, 34 (2): 188-195. doi: 10.7498/aps.34.188
Abstract +
The stimulated Brillouin scattering process under the interaction of high intensity sub-ns pulse laser with plasmas has been investigated, with a larger extent of underde-nse plasma being produced in advance. The occurence of instability of both stimulated Brillouin backscattering and sidescattering can be confirmed simultaneously through careful measurements of the energy and spectrum of the backscattered light, as well as the angular distribution of the sidescattered light, especially its space anisotropy.
A STUDY OF THE ARRIVAL DIRECTION OF COSMIC RAYS WITH AVERAGE ENERGY ABOUT 2×1015 eV
SUN LUO-RUI
1985, 34 (2): 196-204. doi: 10.7498/aps.34.196
Abstract +
From May 1982 to January 1983, more than 17,000 cosmic ray air showers were recorded by the small air shower array in Sydney University. Using X2 test and harmonic analysis to study the arrival direction of the showers, no significant anisotropy has been fond.
STRICT LINEARITY GRADUATION FOR USING RADIOISO-TOPE TRANSIMISION LIQUID LEVEL AND ACTIVITY DISTRIBUTION OF RADIOACTIVE SOURCE
YANG JIE-FU
1985, 34 (2): 205-212. doi: 10.7498/aps.34.205
Abstract +
In this paper, we discuss briefly some work on linear measurement in which the liquid level is obtained by means of radioisotope and put forward a formula of activity distribution of radioactive source that strictly satisfies the requirement of linear graduation. The formula is applicable to designing the linear measurement of liquid level or a place where two fluid media meet, calculating activity distribution of the uneven stick radiator or the uneven point radiators group. In addition, we recommend the application of the formula and the methods of computing and examining the activity distribution of radioactive Source, and analyse briefly the graduation of the type LB3121 γ-liquid level gauge, whose activity distribution of radioactive source is found to satisfy the requirement of linear graduation not so strictly.
ON THE SINGULAR PERTURBATION SOLUTION OF BOLT-ZMANN EQUATION (Ⅲ)——"BOUNDARY LAYER" SOLUTION
DING E-JIANG, HUANG ZU-QIA
1985, 34 (2): 213-224. doi: 10.7498/aps.34.213
Abstract +
The "boundary layer" solution of Boltzmann equation with a small Knudson number is discussed by using a kind of singular perturbation method, and is reduced to solving a set of linear algebraic equations. The dependence of the temperature jump coefficient on the accommodation coefficient is obtained for the Maxwell's boundary conditions.
ON THE SINGULAR PERTURBATION SOLUTION OF BOLTZMANN EQUATION (Ⅳ)——EXTENSION TO NON-MAXWELL MOLECULES
DING E-JIANG, HUANG ZU-QIA
1985, 34 (2): 225-234. doi: 10.7498/aps.34.225
Abstract +
The singular perturbation method used in [1-3] is extended to discuss the solution of Boltzmann equation with small Knudson number for non-Maxwell molecules. It is shown that the method set up in [1-3] and the main conclusions obtained for Maxwell molecules still hold for non-Maxwell molecules under rather general conditions.
THE CRYSTAL STRUCTURE OF Bi2Pb2V2O10
WANG PEI-LING, LI DE-YU
1985, 34 (2): 235-240. doi: 10.7498/aps.34.235
Abstract +
The crystal structure of Bi2Pb2V2O10 has been determined by X-ray single crystal diffraction method. The crystal belongs to triclinic system with space group P1, Z=1 and cell parameters: α=7.084(4)? b=7.278(3) ?, c=5.587(3)?, α=111.91(5)° β=95.01(6)°γ=108.86(4)°ν=245.70 ?3, Dx,=7.35 g/cm, (MoKα)=678.94cm-1, F(000)= 456. The structure was analysed by means of Patterson function and Fourier techniques. The coordinates of atoms, isotropic and anisotropic thermal parameters were refined to R=0.079 for 1054 independent reflections by least-squares refinement procedure. The structure analysis shows that eight O atoms around Pb atom form a polyhedron with 8-vertexes and six O atoms around Bi atom form a polyhedron with 6-ver-texes. Two Pb-0 polyhedra with common edge connect with two Bi-0 polyhedra with common edge. They extend along be plane. The effect of absorption was discussed. Finally, the comparison of the structure of Bi2Pb2V2O10 with Pb2SO5 was made.
BRIEF REPORT
GLOBALLY REGULAR SOLUTION OF CONFORMAL FLAT FOR A CHARGED SPHERE
ZHU SHI-CHANG, ZHU SHI-TONG
1985, 34 (2): 241-247. doi: 10.7498/aps.34.241
Abstract +
In this paper, we discuss a conformal flat interior solution of the Einstein-Maxwell equation for the uniform mass density sphere. This solution satisfies both the dominant and strong energy conditions under some restrictive conditions, it can be a globally regular solution.
ANNIHILATION OF VERTICAL BLOCH LINES IN IN-PLANE FIELD
LI JING-YUAN, YU ZHE-HONG, HAN BAO-SHAN, ZHANG SHOU-GUNG
1985, 34 (2): 248-252. doi: 10.7498/aps.34.248
Abstract +
Hard bubbles and hard wall segments will transform into normal ones, if an in-plane field is larger than a threshold value Hin. We measured the Hin values for some as-grown magnetic bubble materials. As d.c, magnetic bias field perpendiculer to the film increases, Hin decreases. It has been shown that the transformation from hard bubbles and hard wall segments into normal ones is a relaxation proccess which may last for a few seconds or more. The above results were explained qualitatively in terms of the concept of field-nucleated Bloch points suggested by Slonczewski and Maloze-moff.
PHOTO-INDUCED DEGRADATION OF UNDOPED AMORPHOUS SILICON HYDRIDE PREPARED BY D. C. GLOW-DISCHARGE DEPOSITION TECHNIQUE
WU DAO-HUAI, YE JIAN-MING, PAN HUI-YING, CHENG RU-GUANG
1985, 34 (2): 253-258. doi: 10.7498/aps.34.253
Abstract +
Effect of annealing and light illumination on electrical and optical properties of undoped a-Si :H films were studied. The surface energy band bending is created by H20 adsorbats in order to compare the difference between annealing state and light illumination state. The results show that the density of gap state has been increased by light illumination.
AN INVESTIGATION ON COAGULATION EFFECT OF Fe3+ TO OXYGEN IONS IN GLASSES
XIA YUAN-FU, LIU RONG-CHUAN, WANG SHU-XIN, XU CHAO, PAN SHU-YING, CHENG YI-BING
1985, 34 (2): 259-262. doi: 10.7498/aps.34.259
Abstract +
Three Fe2O3 containing alkali-silicate glass systems in which the connection of glass uetwork are different each other are studied by means of M?ssbauer spectro-scopy. It is observed that Fe3+ ions in the glasses have a stronger coagulation effect in comparison with oxygen ions. There are two manifestations of the effect, i.e., the inter-polarization of Fet3+ in tetrahedra and the outer-polarization of Fe03+ in octahedra to the glass hetwork.
7Li NMR STUDIES ON IONIC CONDUCTOR IN THE SOLID SOLUTIONS Li3VO4-Li4TO4 (T = Ge, Si)
LI ZI-RONG, WAN GANG, CHEN LI-QUAN, CHE GUANG-CAN, WANG LIAN-ZHONG
1985, 34 (2): 263-268. doi: 10.7498/aps.34.263
Abstract +
The 7Li NMR spectra of the solid solutions between Li3VO4 and Li4TO4 (T=Ge, Si) with different composition were investigated in the range 150-573 K. It was found that the values of 7Li NMR linewidth and spin-lattice relaxation time T1 in γII phase solid solutions are about an order of magnitude less than that of Li4GeO4, Li4SiO4, and Li3VO4 at room temperature. The temperature dependence of the number and the intensity ratio of 7Li NMR quadrupole satellite lines, and the composition dependence of the former were observed. It is suggested that the Li+ ions in samples of γII structural compositions move probably about one order of magnitude faster than that of the three pure compounds. The number of inequivalent sites occupied by the Li+ ions changes with the composition. The occupancy of the Li+ ions in the inequivalent sites changes with the temperature.
DISTINGUISHING THE TO AND LO MODES OF RAMAN SPECTRA IN OPTICAL ACTIVITY UNIAXIAL CRYSTALS
GU BEN-YUAN
1985, 34 (2): 269-274. doi: 10.7498/aps.34.269
Abstract +
A simple method to distinguish the TO and LO modes of Raman spectra in optical active uniaxial crystals was proposed in this paper. Using 90°scattering geometry configuration x(z+△y, xz)y, the angle between polarization direction of scattering light and x axis is denoted by δ. Applying the formula of Raman scattering efficiency of polar phonons in uniaxial crystal given by Loudon, we found that scattering efficiencies of TO and LO modes depend on components of Raman polarizability tensor and angle d. If δmaxTO and δmaxLO represent the angles at which Raman scattering efficiencies for TO and LO modes take maximum value respectively, it turns out that sign of δmaxTO and δmaxLO is just opposite. Therefore, according to sign (δmax), TO and LO modes can be distinguished, and anisotropy of Raman tensors can be extracted from the absolute values of δmax.
THE ANOMALOUS VIOLET-SHIFT OF ABSORPTION EDGE OF LiNbO3 CRYSTALS OF THE SOLID-LIQUID CONGRUENT POINT COMPOSITION
LIU SI-MIN, ZHANG GUANG-YIN, RONG FANG, WU SI-JIA, KANG WIE, LIU QIU-XIANG
1985, 34 (2): 275-279. doi: 10.7498/aps.34.275
Abstract +
The experimental result of anomalous violet-shift of absorption edge of LiNbO3 crystal of the solidliquid congruent point composition is presented. This resultis conducing for showing that the existence of the solid-liquid congruent point corresponds to the strongest Nb-0 bonding state.
THE SUPERCONDUCTING TRANSITION TEMPERATURE AND THE DENSITY OF ELECTRON STATES OF TERNARY COMPOUNDS SnMo6S8
D. G. HINKS, LI HONG-CHENG
1985, 34 (2): 280-282. doi: 10.7498/aps.34.280
Abstract +
It is shown in this paper that the Pauli susceptibility of the ternary compound SnMo6S8 decreases as the oxygen content increases. The change of Tc deduced from susceptibility using BCS theory is consistent with experiments.
SOUND-LIKE COLLECTIVE MODE EXCITATION WITH PION ABSORPTION IN NUCLEAR MATTER
QIU XI-JUN, SHEN JIAN-GUO, HUANG LING-FANG
1985, 34 (2): 283-288. doi: 10.7498/aps.34.283
Abstract +
The relativistic mean field theory consistent with bulk properties of nuclear matter is extended to study the excitations of the sound-like collective modes in nuclear matter. Corresponding relativistic mean field equations are solved numerically and self-consis-tently. The effective mass of nucleon the speed of the sound and the amplitude of the sound-like solution are calculated. When the nuclear density is near or greater than the saturation density, the sound-like non-trivial solution could be found.