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Volume 7 Issue 2
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Original Articles
NEW CYLINDRICALLY GRAVITATIONAL WAVE SOLUTIONS
ZHONG Zaizhe
Chin. Phys. Lett. 1990, 7 (2): 49-52 .  
Abstract   PDF(pc) (40KB) ( 389 )
A method is presented by which an infinite series of new dual solution pairs of cylindrically symmetric vacuum Einstein equations can be generated. A new cylindrical gravitational wave solution is given and discussed.
SCALE BEHAVIOR OF CP NONCONSERVATION
JIN Changhao
Chin. Phys. Lett. 1990, 7 (2): 53-56 .  
Abstract   PDF(pc) (44KB) ( 306 )
The scale dependence of the three-generation phase-invariant measure of CP nonconservation is revealed by solving the coupled renormalization group equations. Employing a careful calculation scheme, we find the CP nonconservation measure, contrary to the previous studies, decreases with energy.
CONTRIBUTIONS OF NUCLEAR CORE POLARIZATION TO Ovββ DECAY OF 48Ca MEDIATED BY HEAVY NEUTRINO
SONG Hongqiu, WU Huifang*
Chin. Phys. Lett. 1990, 7 (2): 57-60 .  
Abstract   PDF(pc) (52KB) ( 349 )
Nuclear core polarization processes in the Ovββ decay of 48Ca are discussed in a diagrammatic effective operator approach. The main effect of these processes is to increase the limit on heavy neutrino mass of about 8%.
APPLICATION OF THE SHIFTED 1/N EXPANSION TO A MORE GENERAL SCREENED COULOMB POTENTIAL
FAN Xijun, YUAN Zhifang, WANG Xiangtai
Chin. Phys. Lett. 1990, 7 (2): 61-63 .  
Abstract   PDF(pc) (35KB) ( 327 )
Sever and Tezcan recently [Phys.Rew.A36(1987)1045], used the 1/N expansion to solve the time independent Schrodinger equation with a more general scrcened Coulomb potential; V (r) = -(a/r)[l + (1 + br) exp(-2br)] obtained the analytical expressions, and gave some numerical values of energies for 1s and 2s states. We apply the shifted 1 / N expansion to solve the same Schrödinger equation and calculate the numerical values of energies for 1s to 5g states. Our results for 18 and 2s states are excellent agreement with those obtained by solving the Schrodinger equation by means of the numerical calculation method, and the accuracy is much better than the results of Sever and Tezcan.
GENERALIZATION TO CYLINDRICAL COORDINATE SYSTEM FOR THE HIGHER ORDER KDV AND KP EQUATION
HUANG Guoxiang, DAI Xianxi, LOU Senyue*
Chin. Phys. Lett. 1990, 7 (2): 64-67 .  
Abstract   PDF(pc) (45KB) ( 333 )
Two new model equations which we call a higher order cylindrical KdV equation and a higher order cylindrical KP equation are proposed when we consider the 2-dimensional modulation of water waves with surface tension in cylindrical coordinate system. Some exact (2+1)-dimensional solitary wave solutions have been obtained by relating them to the higher order KdV equation through an appropriate variable transformation.
BIFURCATION, CHAOS AND HYSTERESIS IN ELECTRODYNAMIC CONE LOUDSPEAKER
MIAO Guoqing, NI Wansun, TAO Qintian, ZHANG Zhiliang, WEI Rongjue
Chin. Phys. Lett. 1990, 7 (2): 68-71 .  
Abstract   PDF(pc) (58KB) ( 718 )
The phenomena of bifurcation, chaos and hysteresis of electrodynamic cone loudspeaker have been investegated experimentally in mid-frequency range. The frequency spectrum, as well as the phase diagram in frequency-voltage phane, of bifurcation and chaos is given. The hysteresis phenomenon is observed clearly from frequency response curve.
FURTHER INVESTIGATION ON REFLECTION AND REFRACTION OF FINITE AMPLITUDE SOUND WAVE
QIAN Zuwen, ZHENG Xiaoyu
Chin. Phys. Lett. 1990, 7 (2): 72-74 .  
Abstract   PDF(pc) (32KB) ( 447 )
Based on the authors' former work, a study on reflection and refraction of finite-amplitude sound wave was carried out. A solution completely satisfying the continuity conditions was obtained by means of the method of making the inhomogeneous terms of the wave equation to be determined.

ELECTRONIC STRUCTURE OF CHALCOGENIDE COMPOUNDS
LU Yanwu, WANG Dingsheng*, RONG Ailun
Chin. Phys. Lett. 1990, 7 (2): 75-78 .  
Abstract   PDF(pc) (50KB) ( 481 )
Empirical linear combination of atomic orbitals (LCAO) calculations are performed to investigate the electronic structure of Sb2Se3, Sb2Te3, In2Se3 and In2Te3. The bands of bonding p states are overlapped with the bands of lone pair states in these materials. The absorption edges of these materials correspond to indirect gap, and the calculation agrees with experimental values.
INVESTIGATION OF NITROGEN CONTENT INFLUENCE ON ELECTRON SPIN RESONANCE IN a-Si:H/a-SiNx:H MULATLATYERS
LIU Xiangna, ZHAO Zhouyin*, WANG Yong
Chin. Phys. Lett. 1990, 7 (2): 79-82 .  
Abstract   PDF(pc) (51KB) ( 501 )
Influence of nitrogen content on electron spin resonance (ESR) in a-Si:H/a-SiNx:H multilayers is studied, associated with infrared absorption analysis. The spin density decreases rapidly in the region x>~ 0.7 and approaches a saturated value, which is much less than common assumption. The results are explained in terms of the structure relaxation due to the increase of N-H bonds with increasing x and the transfer doping across interfaces.
INTERPRETATION OF ANOMALOUS QUANTUM SIZE EFFECTS IN PbTe-Bi SUPERLATTICES
YANG Ruiqing
Chin. Phys. Lett. 1990, 7 (2): 83-84 .  
Abstract   PDF(pc) (29KB) ( 309 )
A new theoretical interpretation for the anomalous quantum size effects in PbTe-Bi superlattices has been proposed. The calculated thickness of Bi layers at which the semimetal-semiconductor transition occurs is in good agreement with the experimental data.
ANOMALIES IN ULTRASONIC ATTENUATION OF Pb-DOPED Bi2Sr2CaCu2O8+x SUPERCONDUCTORS AT Tc
DONG Jian, DENG Tingzhang, LI Fengying, YAO Yushu
Chin. Phys. Lett. 1990, 7 (2): 85-88 .  
Abstract   PDF(pc) (49KB) ( 314 )
At the transition from normal to superconducting states there were anomalies of ultrasonic attenuation in single-phased specimens Bi2-xPbx Sr2 CaCu2 Oy ( Tcmid=80K); and as the temperature was lowered below Tcmid, the attenuation decreased rapidly. At the temperature about 135K there was a relatively high peak, which may be due to a certain relaxation process.
MAGNETIC MOMENT AND CURIE TEMPERATURE OF AMORPHOUS (Fe100-xBx)88 Nd12±ε ALLOYS
SHEN Baogen, ZHAO Jiangao, ZHANG Zhiying, GU Benxi, DING Jun, H. Homburg and S. Methfessel
Chin. Phys. Lett. 1990, 7 (2): 89-92 .  
Abstract   PDF(pc) (49KB) ( 409 )
The magnetization curves at 1.5K and Curie temperature of amorphow (Fe100-xBx)88 Nd12±ε alloys were measured. Their spontaneous magnetizations is explained by a noncollinear structure. The average magnetic moment μFe per Fe atom decreases monotonically with increasing x, and becomes more rapid when x > 24. The B content dependence of Curie temperature shows a mazimum at x = 15. At x< 15, the increase of Tc with x may be attributed to the indirect exchange interactions between Fe-Fe atoms.
DOMAIN-WALL OSCILLATION OF STR.IPE LATTICES IN GARNET FILMS
BI Siyun
Chin. Phys. Lett. 1990, 7 (2): 93-96 .  
Abstract   PDF(pc) (62KB) ( 363 )
The domain-wall resonance(DWR) frequencies of stripe lattices in the garnet films, as a function of the in-film magnetic field Hp, have been measured. The samples were grown by liquid, phase epitaxy(LPE) ,on (111) GGG substrates. The experiments were carried out with the h.f. magnetic field parallel and perpendicular to the stripe domains, respectively. In addition, as the applied magnetic field was rotated out of the film gradually, the variation of the DWR frequencies was also investigated.
13 articles