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Vol. 31, No. 4 (1982)

1982-02-20
CONTENT
PLASMA KINETIC EQUATION IN THE PRESENCE OF BOTH CONSTANT ELECTRIC AND MAGNETIC FIELDS
QIN YUN-WEN
1982, 31 (4): 419-426. doi: 10.7498/aps.31.419
Abstract +
A kinetic equation for uniform plasma in the presence of both constant electric and magnetic fields was obtained by the method of micro-density in the phase space.
SPACE FREQUENCY BANDWIDTH OF RAINBOW HOLOGRAM AND ORDINARY HOLOGRAM
CAI LI-ZHONG, ZHANG YOU-WEN, ZHU WAI-GUANG
1982, 31 (4): 427-436. doi: 10.7498/aps.31.427
Abstract +
According to the Fresnel-Kirchhoff diffraction theory, we have analyzed systematically the space frequeney bandwidth of rainbow hologram and ordinary hologram as the object, slit, reference source and holographic plate are in different relative positions. For each of these cases, a universal fomula of frequency bandwidth has been derived, it is suitable not only to rainbow hologram but also to ordinary hologram. The theory given here may be useful for space frequency bandwidth compression and plate choice.
A METHOD TO ACHIEVE OPTICAL MULTI-CHARACTERISTIC PATTERN RECOGNITION
LIU JI-LIN, DAI JIAN-HUA, ZHANG HONG-JUN
1982, 31 (4): 437-445. doi: 10.7498/aps.31.437
Abstract +
The projections of an input image on the Schmidt orthogonalized basis functions are determined from the crosscorrelation matrix of the input and the reference image, so a novel method for multi-characteristic pattern recognition has been provided. The experimental demonstrations are in agreement with the theory.
BISTABLE CHARACTERISTICS OF HYBRID NONLINEAR FABRY-PEROT OPTICAL BISTABILITY
LI YONG-GUI, ZHANG HONG-JUN, YANG JUN-HUI, GAO CUN-XIU
1982, 31 (4): 446-459. doi: 10.7498/aps.31.446
Abstract +
In this paper, we describe a hybrid nonlinear P-P Bistable Optical Device (BOD), the length of its cavity is controllable. The dynamic equations of the system and the equilibrium splution which shows the optical bistable nature are given. The bis-tability and linear modulation characteristics are discussed. The stability of the equilibrium state and the "critical slowing down" effect of transient behavior are analysed. The experimental demonstrations are in agreement with the theoretical evaluations.
THE SECONDARY EXTINCTION CORRECTION IN SINGLE CRYSTAL STRUCTURE ANALYSIS
GAO YU-MING, LI DE-YU
1982, 31 (4): 460-466. doi: 10.7498/aps.31.460
Abstract +
In this paper, a procedure and its computer program for including secondary extinction as a parameter in crystal structure least-squares analysis are described. The effect of its use in some crystal structure analysis refinements is also given.
A STUDY OF THE INFLUENCE OF ADDITIVE AGENTS (2Fe)· Sn ON X-RAY DIFFRACTION RELATIVE INTENSITY I200/I111 OF PERMANENT MAGNET SmCo5
LU YUN-JIN, YANG XING-SHUI, ZHAO JI-WAN, WANG GUI-QIN, ZHANG SHI-YUAN, LIU CHANG-QING
1982, 31 (4): 467-473. doi: 10.7498/aps.31.467
Abstract +
The effect of entering of Fe-atoms and Sn-atoms into crystal lattice of permanent magnet SmCo5 on the X-ray diffraction relative intensities is studied. It is observed that the Fe-atoms can replace the Co-atoms on any site, but they replace Co2c more readily.However, the Sn-atoms replace the Co-atoms or 3 g sites more easily. The replacement of Co-atoms by the Sn-atoms can increases the ratio of X-ray diffraction relative intensity I200/I111, but the striking changes of this ratio is largely due to the alignment, the order of Fe, Sn atoms, the improvement of internal stress conditions, and the controlling of the ~750℃ phase transformation.
A TIGHT-BINDING CALCULATION OF ELECTRONIC STATES OF LAYERED ULTRA-THIN COHERENT STRUCTURES
XIONG SHI-JIE, CAI JIAN-HUA
1982, 31 (4): 474-484. doi: 10.7498/aps.31.474
Abstract +
The present article gives an account of a calculation of the sub-band structure and atomic plane projected electronic local densities of states of a simplified model of the newly appeared synthetic materials, Layered Ultra-thin Coherent Structures (LUCS), by means of the Green's function method in the tight-binding approximation including the nearest neighbor matrix elements only. A formulation of a more accurate method for the same purpose in terms of linear combinations of muffin-tin orbitals and interface plane wave orbitals is given in the appendix.
A STUDY OF THE SUPER-CONDUCTIVITY OF FAST QUENCHED Al-Si ALLOY
GUAN WEI-YAN, CHEN XI-SHEN, WANG ZU-LUN, YI SUN-SHENG, LIN YING
1982, 31 (4): 485-502. doi: 10.7498/aps.31.485
Abstract +
The effect of heat treatment on the microstrueture and Superconducting properties of the eutectic alloy Al- 11.3 at % Si prepared by the splat quenching technique has! been studied. The results of structure analyses indicated that the rapidly cooled Al-11.3 at % Si alloy consists of two phases: a supersaturated α-Al(Si) solid solution and an amorphous phase of Al and Si atoms which are distributed statistically. After annealing at 100℃ for 50 hr. the Si content of the solid solution phase is reduced and some dispersive Si granules separate out from the amorphous phase. After annealing at 200℃ for 100 hr. the specimens precipitated completely. Superconducting transition temperature Tc was measured. The anomalous magnetoresistivity in supereondueting-normal transitions has been found in the sample after annealing at 100℃ for 50hr. Our results reveal the existence of two superconducting phases in this sample.
BRIEF REPORT
ON THE THIRD ORDER OPTICAL NONLINEARITY NEAR EXCITON LINES
GAN ZI-ZHAO, YANG GUO-ZHEN
1982, 31 (4): 503-509. doi: 10.7498/aps.31.503
Abstract +
In this paper, a theoretical method is presented to calculate the third order optical susceptibility which is induced by the saturation effect of light absorption near exeiton lines. In particular, the numerical results of the nonlinear susceptibility are given in both exeiton lines of GaAs and exeiton lines of the yellow series of Cu2O.
THE DIFFERENTIAL CURVE OF Tc WITH RESPECT TO λ
LIU CHANG-WEN, WU HANG-SHENG
1982, 31 (4): 510-515. doi: 10.7498/aps.31.510
Abstract +
In the present paper, the conclusion we arrive through analyzing the (dTc/dλ)-λ curve is that the Tc-λ curve is composed of three parts with entirely different properties, namely, "McMillan region", "λn region" and "series solution region". This conclusion is identical with that obtained in paper [20] except that the value of n is, in general, not equal to 1.55 but is a real number larger than 0.5 and varies with, the shape of the effective phonon spectrum.
SOME COMMENTS ON THE TRANSPORT PROCESSES IN A STRONG MAGNETIC FIELD
HUO YU-PING
1982, 31 (4): 516-518. doi: 10.7498/aps.31.516
Abstract +
This short note elucidates some points of the ref, [1] It is pointed out that to introduce the macroscopic current operator into the quantum theory of transport processes in strong magnetic field is necessary and reasonable.
FEYNMAN'S PATH-INTEGRAL METHOD AND HAWKING EVAPORATION
LIU LIAO
1982, 31 (4): 519-524. doi: 10.7498/aps.31.519
Abstract +
Though there are various methods in deriving the Hawking evaporation formula, but all of them depend on explicit forms of the space-time metrics. Not long ago, we have put forward a conjecture. "Independent of the explicit forms of space-time metrics, every static or stationary space-time with furture horizon must have Hawking evaporation." Now in this paper, we give a full proof of this conjecture.
QUARKONIUM POTENTIAL MODEL WITH A NON-ZERO GLUON EFFECTIVE MASS
LIN DA-HANG, ZHAO PEI-ZHEN, HE ZUO-XIU
1982, 31 (4): 525-531. doi: 10.7498/aps.31.525
Abstract +
Aecording to Parisi's suggestion, we assume that the gluon possesses a non-zero effective mass μ. From this assumption, we derive an effective Hamiltonian up to order β2 for quarkonium. For μ = 0.8 GeVand 0.4 GeV, we find the spectra as well as the relative leptonic widths for charmonium and upsilon, which are in good agreement with experiment.
THE CRYSTAL AND MOLECULAR STRUCTURE OF DIHYDROXY-ETHYLENEDIAMINE-MALONATOPLATINUM
XU XIAO-JIE, ZHANG ZE-YING, TANG WEN-XIA
1982, 31 (4): 532-536. doi: 10.7498/aps.31.532
Abstract +
The crystal structure of Pt(en) (mal) (OH)2H2O has been determined from three-dimensional X-ray data collected by Syntex P3/R3 four circle diffractometer. The crystal is triclinic with space group P1, α =8.4526(15)?, b=6.0947 (8)?, c=10.1854 (15)?, α = 106.48°(I), β= 103.65°(I), γ= 79.12° (I), and Z = 2. The crystal structure has been solved by Patterson method and refined by block least square refinement for positional parameters and anisotropic tempreture factors of nonhydrogen atoms. The final R factor is 0.055.The result of crystal structure analysis shows that the platinum atom is inovolved in a d2sp3 hybridization and an octahedral configuration.
CRYSTAL STRUCTURE OF LiNdP4O12
LIU JIAN-CHENG
1982, 31 (4): 537-542. doi: 10.7498/aps.31.537
Abstract +
A single-crystal X-ray diffraction analysis has been performed on LiNdP4O12synthesized by the flux method. The crystal belongs to monoclinic system, with space group C2/c, z=4, and cell parameters α= 16.486?, b = 7.073 ?, c =9.775? and β = 126.23°. A full-matrix, least square refinement gave R = 0.054, Rω= 0.050 for 1251 independent reflections. An absorption and secondary extinction refinement gives final R = 0.048. Rω = 0.043. The basic structural units are helical ribbons, (PO3)n, formed by corner-sharing of PO4 tetrahedra. The NdO8 dodecahedra are isolated from each other in the sense that they do not share any O atoms.
THE STRUCTURE DETERMINATION OF 3,4-METHYLENEDIOXY-CINNAMOYL PIPERIDIDE
LIN GUANG-DA, SHEN FU-LING, ZHENG QI-TAI
1982, 31 (4): 543-546. doi: 10.7498/aps.31.543
Abstract +
The crystal structure of 3, 4-methylenedioxy-cinnamoyl piperidide, a clinical an-tiepiletic remedy, was determined. The molecular formula is C15H17O3N1. The crystal belongs to the orthogonal system. The space group is D24-P21 21 21. The lattice parameters are: α = 24.338 (4)?, b = 8.558 (2)?, c = 6.217 (2)?, and Z = 4. The intensity data were collected on PW-1100 automated four-circle diffractormeter. The structure was solved by the direct method (MULTAN-78), R =0.2469. The significance of the structural determinations of Cinnamamides was also discussed.
THE CRYSTAL STRUCTURE AND MOLECULAR ABSOLUTE CONFIGURATION OF KOUMINE HYDROBROMIDE
RAO ZI-HE, WAN ZHU-LI, LIANG DONG-CAI
1982, 31 (4): 547-553. doi: 10.7498/aps.31.547
Abstract +
The crystal structure of alkaloide, koumine Hydrobromide (C20H22N2O·HBr), has been solved by Patterson and Fourier methods and refined to an R value of 0.067 by full-matrix least-square method. The crystal belongs to orthorhombic system with the unit cell parameters: a = 14.307?, b = 12.053?, c = 9.862?; and four molecules are contained in the cell. The space group is P21 21 21. The positions of all hydrogen acoms have been found from a difference Fourier map calculated after the refinement of co-ordinates of all non-hydrogen atoms with anisotropic thermal parameters by least-squares method. The absolute configuration of the molecule has been established. The structural characteristics of the molecule were discussed.
THE CRYSTAL STRUCTURE AND ABSOLUTE CONFIGURATION OF QUININE SALT OF (+)-O-ETHYL O-PHENYL PHOSPHOROTHIOIC ACID
TANG CHU-CHI, WU GUI-PING, DOU SHI-QI, ZHENG QI-TAI, DAI JIN-BI
1982, 31 (4): 554-560. doi: 10.7498/aps.31.554
Abstract +
The crystal of Quinine salt of (+)-0-ethyl O-phenyl phosphorothioic acid belongs to orthorhombic system with space group D24-P21 21 21 and cell parameters a= 29.007 (7)?, b = 14.089 (4)?, c = 6.589 (3)?. There are four molecules ia each unit coll, Z= 4. X-Ray diffraction intensity data are collected on PW-1100 four-circle diffracto-meter, using CuKα radiation. The number of independent diffraction data amounts to 2818, and 2463 are observable reflections. The crystal structure has been determined by direct method (MULTAN-78). The structure parameters were refined by full-matrix least-square method to R=0.082. The absolute configuration has been assigned by direct measurement of 18 enantioner-sensitive Bijvoet reflection pairs. The properties of P-O, P-S bond types were discussed.