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Volume 4 Issue 4
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Original Articles
DIELECTRIC RESPONSE OF A SEMICONDUCTING CERAMIC BASED ON BARIUM TITANATE
ZHANG Peilin, ZHONG Weilie, SHEN Chenghang, LIU Sidong
Chin. Phys. Lett. 1987, 4 (4): 145-148 .  
Abstract   PDF(pc) (46KB) ( 374 )
Complex dielectric constant ε=ε'-iε" of a semiconducting BaTiO3 ceramics has been measured at room temperature over the frequency range of 10kHz-500MHz. This dielectric response can be approximately described by the Debye type relaxtion equations, whereas the conductivity dominates the imaginary part at lower frequencies. From the dielectric measurement, the resistivity and the dielectric constant have been evaluated for the grains and grain boundaries separately.
LAYERED IMAGING OF PHOTOACOUSTIC MICROSCOPY BY PHASE SELECTING
CHEN Li, ZHANG Shuyi,
Chin. Phys. Lett. 1987, 4 (4): 149-152 .  
Abstract   PDF(pc) (64KB) ( 333 )
The theoretical prediction and experimental detection for photoacoustic layered imaging by selecting the signal of proper phase angle are described. Using this technique, we can increase the contrast of the subsurface features and suppress the surface influence. Some experimental results of layered imaging are presented.
A PROPOSED NEW DESCRIPTION OF LINEAR OSCILLATORS
HUANG Xiangyou
Chin. Phys. Lett. 1987, 4 (4): 153-156 .  
Abstract   PDF(pc) (35KB) ( 427 )
A suggestion to define the state of an oscillator by two wave functions is proposed. These two functions can be combined to completely describe the motion of the oscillator. In this description, both the energy and the phase of the oscillator simultaneously have definite values. The usual theory of oscillators is a statistical case of the new description.
SHELL EFFECT IN TRANSITION MATRIX ELEMENT OF TWO-BODY RESIDUAT, INTERACTION
CHENG Yehao, ZHAO Kui, LI Qingli, HAN Shukui, YU Quan, XU Jun, LOU Yunian, ZHOU Guihua, JIANG Chenglie
Chin. Phys. Lett. 1987, 4 (4): 157-160 .  
Abstract   PDF(pc) (49KB) ( 346 )
The prediction that there might be shell effect in pre-equilibrium emission of (α, p) reaction is true. It seems that there is also shell effect in the change of the average value of the square of transition matrix element of two-body residual interaction with different target nuclei at the lower excitation energy.
THE EXPERIMENTAL DETERMINATION OF THE NUCLEAR SPIN RELAXATION OF 129Xe
LI Senling, SUN Xianpin, TANG Tianrong, ZENG Xizhi, WANG Feng
Chin. Phys. Lett. 1987, 4 (4): 161-164 .  
Abstract   PDF(pc) (42KB) ( 394 )
Spin-exchange collisions between polarized 87Rb atoms and unpolarized 129Xe nuclei have been used to produce nuclear spin polarized 129xe. Measurements of the longitudinal relaxation rate of 129Xe nuclear polarization have been carried out in a 5.7G magnetic field. The present results show that the nuclear spin relaxation rate of 129Xe in 87Rb vapor is proportional to the density of the 87Rb atoms, and the nuclear spin relaxation rates of 129Xe induced by the 87Rb atoms depend on the pressure of the buffer gas N2.

THE INFLUENCE OF ADDITIVE Dy2O3 ON THE MAGNETIC PROPERTIES OF Nd16(Fe0.96A0.04 )77B7 ALLOY
NIE Jianfeng*, WANG Jianhua*, LIU Yinglie, LIN Wengui, JI Songquan, ZHANG Shougong, MAO Tingde
Chin. Phys. Lett. 1987, 4 (4): 165-168 .  
Abstract   PDF(pc) (42KB) ( 351 )
The influence of additive Dy2O3 on the magnetic properties of Nd16(Fe0.96A0.04 )77B7 has been investigated. It is shown that when the Dy2O3 concentration is 4wt% the intrinsic coer-civity iHc of the sintered magnets increases to 17850 Oe.
PHASE TRANSITION OF THE DISPERSED SYSTEM LiIO3(γ-A12O3)
CHEN Liquan
Chin. Phys. Lett. 1987, 4 (4): 169-172 .  
Abstract   PDF(pc) (57KB) ( 387 )
The increase of phase transition temperatures both from α-to γ-phase and from γ-to β-phase of LiIO3 in the dispered system LiIO3 (γ-A12O3) has been observed. The -phase can be stabilized to ambient condition by the presence of γ-A12O3. The stability of γ-A12O3 and -LiIO3 is improved by the addition of γ-A12O3.

BAG SKIN EFFECT FOR FRIEDBERG-LEE MODEL
ZHU Wei
Chin. Phys. Lett. 1987, 4 (4): 173-176 .  
Abstract   PDF(pc) (39KB) ( 347 )
Importance of the bag skin effect to determine the parameters of the Friedberg-Lee model is pointed out. The European Muon Collaboration (EMC) effect regarded as a bag skin effect can be used to determine the parameters of this model.
PULSAR DRIFT AND ROTATIONAL COLLAPSE
Asghar Qadir*, M. Rafique, A.W. Siddiqui*
Chin. Phys. Lett. 1987, 4 (4): 177-180 .  
Abstract   PDF(pc) (49KB) ( 382 )
The relativistic explanation of pulsar drift is based on an extremely simplistic model. The collapsing star is treated as composed of a collection of particles falling radially inwards. A calculation incorporating a finite angular momentum is found to give reasonable drift velocities provided the initial pulsar frequency is sufficiently high. The values required are not unreasonable.
THE MICRO-MORPHOLOGY OF THE SOLID-LIQUID INTERFACE ON CZOCHRALSKI-GROWN LiNbO3 SINGLE CRYSTAL
JIN Weiqing, JIN Jiren, ZHOU Weiqing
Chin. Phys. Lett. 1987, 4 (4): 181-184 .  
Abstract   PDF(pc) (69KB) ( 399 )
The micro-morphology of the interface transition from (01 ī 2) facet to freezing isotherm curve has been observed. In the centre of the interface (the high supercooling region), the morphology of (01 ī 2) facet shows characteristics of terrace-step-kink structure. By reducing supercooling, the growth interface gradually turn to agreeing with the freezing isotherm curve.
MULTI-SOLITON SOLUTIONS OF COUPLED NONLINEAR SCHRODINGER EQUATIONS
YAN Zhida
Chin. Phys. Lett. 1987, 4 (4): 185-188 .  
Abstract   PDF(pc) (38KB) ( 435 )
The 1+1 and 1+1+1 soliton solutions with different polarization for coupled nonlinear Schrodinger (NLS) Equations have been obtained by using Bilinear Method. The asymptotic behaviour and the polarization of these solutions are discussed.
PHOTOREFLECTANCE OF GaAs DOPING SUPERLATTICES
WANG Ruozhen*, ZHAO Mingshan*, LIN Zhenjin*, HAN Zhiyong, JIANG Desheng, LIANG Jiben, ZHUANG Weihua
Chin. Phys. Lett. 1987, 4 (4): 189-192 .  
Abstract   PDF(pc) (48KB) ( 348 )
Photoreflectance of GaAs doping superlattices has been measured at 300K. The spectra exhibits features corresponding to spatially direct transitions due to quantized electron or hole states. We demonstrate the utility of the photoreflectance technique for studying quantum size effects in doping superlattices.


12 articles