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Volume 4 Issue 9
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Original Articles
ONE MAJOR PHASE IN HIGH TC Y-Ba-CU-O DETERMINED BY ELECTRON DIFFRACTION
ZOU Bensan++, GU Hui, ZHANG Jinlong+, ZHANG Cungui+++, YIN Daole+
Chin. Phys. Lett. 1987, 4 (9): 385-388 .  
Abstract   PDF(pc) (48KB) ( 483 )
A major phase in high Tc Y-Ba-Cu oxide with zero resistance at 91K and high volume fraction of diamagnetic superconductive phase has been identified by electron diffraction. It appears to be an orthorhombic twinned structure with a=3.89Å, b=3.82Å and c=11.7lÅ. Some defects were observed by TEM.
FIM STUDY ON THE RELAXATION AND CRYSTALLIZATION PROCESSES OF A Cu-Zr AMORPHOUS ALLOY
H .Lu (LU Hua), D.S. Tang(TANG Disheng), Y.Y. Xiong(XIONG Yanyun)
Chin. Phys. Lett. 1987, 4 (9): 389-392 .  
Abstract   PDF(pc) (78KB) ( 351 )
The relaxation of the Cu-50at.%Zr amorphous alloy was revealed by FIM as a process of formation of clusters consisting of 2.3. or 4 atoms, Which afterwards migrate towards some definite centers, predominantly the quenched-in 'embryos', to construct ordered structure. This dynamic picture, so far as we know, is observed for the first time. Crystallized regions were determined by atom-probe analysis as Cu10Zr7 phase, and the coexisting phase CuZr2 was not revealed simultaneously.
ION-BOMBARDMENT-ENHANCEC DIFFUSION PHENOMENON IN Pb-Sn ALLOY
NI Yuhong, ZHANG Qiangji, LU Quankang, HUA Zhongyi
Chin. Phys. Lett. 1987, 4 (9): 393-396 .  
Abstract   PDF(pc) (42KB) ( 438 )
The surface phenomena of Pb-Sn alloy under the Ar+ ion bombardment have been investigated by using a PHI-590 scanning Auger microprobe at room temperature. Theoretical analysis of experimental data showed that ion-bombardment-enhanced diffusion had occurred with a diffusion coefficient up to 10-15cm2 /sec. A possible explanation is given.
THE EINSTEIN AND DE SITTER UNIVERSES UNDER THE HARMONIC CONDITION
HUANG Chaoguang, CHOU Peiyuan
Chin. Phys. Lett. 1987, 4 (9): 397-400 .  
Abstract   PDF(pc) (38KB) ( 391 )
Under the harmonic condition the Einstein and the static de Sitter universes in relativistic cosmology are again solved. According to the view that the harmonic condition is a physical one, the size of the static de Sitter universe is infinite.
A COMMENT ON THE INVERSE SCATTERING METHOD FOR SOLVING THE NONLINEAR SCHRODINGER EQUATION
CHEN Zongyun*, HUANG Nianning
Chin. Phys. Lett. 1987, 4 (9): 401-404 .  
Abstract   PDF(pc) (34KB) ( 441 )
Disregarding that the locations of poles of the transmission coefficient must be in the upper half-plane of k that is given by the usual inverse scattering method, solutions of the nonlinear Schrodinger equation are found from the Gelfand-Levitan-Marchenko equation by taking the poles at arbitrary places in the complex k-plane. By using the technique of matrix calculation, a simple method is given for directly verifying the solutions in satisfying the nonlinear Schrodinger equation. As an example, new solutions corresponding to the locations of two poles in pairs symmetrically about the origin of the complex k-plane is given and its regularity is shown.
DEEP GROUND STATES RELATED TO Fe IN GaAs1-xPxALLOY SYSTEM
GU Yiming, HUANG Mingzhu, WANG Keling
Chin. Phys. Lett. 1987, 4 (9): 405-408 .  
Abstract   PDF(pc) (47KB) ( 403 )
A theory suggested by Vogl et al . is extended to the iron-doped GaAs1-xPx alloy system. The deep ground states (including acceptor ( Fe/Fe ) levels, donor ( Fe/Fe ) levels, local charges and spin densities ) are predicted for different composition X. The calculated results show good agreement with the relevant experimental data and reveal their variation trends.


ANOTHER SO(7) SUBALGEBRA IN GINOCCHIO’S MODEL
LING Yinsheng
Chin. Phys. Lett. 1987, 4 (9): 409-412 .  
Abstract   PDF(pc) (34KB) ( 410 )
There are three subalgebra chains in Ginocchlo's so ( 8 ) model. The subalgebra so ( 5 ) + su ( 2 ) and so ( 7 ) are maximum subalgebras in so ( 8 ). The subalgebra so ( 6 ) is not this case. We can find a new subalgebra so ( 7 ) between the so ( 8 ) and so ( 6 ). It is useful in the calculation at least.

STUDY ON INFRARED SPECTRA OF CDF3 EXCITED STATES
SONG Quan, KUANG Liping, XIE Hui, KUANG Yizong
Chin. Phys. Lett. 1987, 4 (9): 413-416 .  
Abstract   PDF(pc) (58KB) ( 401 )
Vibrationally excited spectra of CDF3 have been studied with a CO2 laser and FTIR spectrometer. Seven difference bands are observed in the experiment. The anharmonic constants determined from these bands agree with the calculated result by Kirk et al. according to its isotopic species CHF3 [J. Mol. Spectrosc. 58(1975)102].
SOME RESEARCH ON DIFFUSION-LIMITED AGGREGATION
WENG Jiaqiang, ZHOU Changan
Chin. Phys. Lett. 1987, 4 (9): 417-420 .  
Abstract   PDF(pc) (51KB) ( 318 )
This paper, using the rule of condensation proposed by Botet and Jullien in 1985, investigates a diffusion-limited aggregation model, which shows that the fractal dimension is bigger than used by Witten-Sander model. And also, by using the statistical method to 100 clusters, calculates the growth probability of each layer of a cluster. Futhermore, a growth probability model equivalent to the statistical average state of diffusion-limited aggregation is proposed.
INFORMATION ON NEUTRINO MASSES OBTAINED FROM SUPERNOVA 1987a DATA
CHEN Zhongmo, GOU Liang*, MA Zhongqi*, ZHOU Xianjian*
Chin. Phys. Lett. 1987, 4 (9): 421-423 .  
Abstract   PDF(pc) (34KB) ( 382 )
Under the assumption that all the neutrino events in the observation of KAMIOKANDE-11 detector on February 23, 1987, may be produced from one short neutrino burst in the Supernova 1987a within a few tenths of second, these neutrino events can be divided into three groups with neutrino masses 4.15eV. 18.7eV and 28.5eV, respectively.

NEUTRINO MASS AND SUPERNOVA 1987A
FANG Lizhi
Chin. Phys. Lett. 1987, 4 (9): 424-426 .  
Abstract   PDF(pc) (30KB) ( 391 )
If the rest mass of electron neutrinos is non-zero, the arrival times of neutrinos emitted from supernova 1987a will be dispersed due to the dependence of neutrino speed on their energy. By using this effect, an upper limit of the neutrino mass, 5-10eV/c2, can be derived from the data of neutrinos recorded by Mont Blanc neutrino observatory.
MECHANISM OF HIGH Tc SUPERCONDUCTIVITY IN Ba-La-Cu-O
LIU Fusui, SHENG Yi, DAI Yuandong
Chin. Phys. Lett. 1987, 4 (9): 427-429 .  
Abstract   PDF(pc) (34KB) ( 358 )
It is proposed that the high Tc superconductivlty in Ba-La-Cu-O system comes from the phonon cloud mediated Fröhlich polaron pair. The Tc should be lower than the transition temperature of small polaron into large polaron. Estimated value of Tc is also given based on the mechanism proposed by the authors.


PREPARATION OF AMORPHOUS Mn-Zn FERRITES AND THEIR MAGNETIC PROPERTIES
YIN Zhiying, WANG Jingyin, LI Jine
Chin. Phys. Lett. 1987, 4 (9): 430-432 .  
Abstract   PDF(pc) (34KB) ( 598 )
This paper describes the preparation of amorphous Mn-Zn ferrites, presents part of the results of the measurements, and the analysis of the samples.
13 articles