空间科学学报

1993 Vol. 13, No. 3

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A NUMERICAL SIMULATION ON THE EXPANSION OF STRONG MAGNETIC FIELD STRUCTURE IN THE INTERPLANETARY SPACE

He Shuang-hua, Zhang Gong-liang

1993, 13(3): 165-173. doi: 10.11728/cjss1993.03.165

Abstract(1698) PDF 513KB(693)

Abstract:
This paper studies the expansion effects of strong magnetic field structure (SMFS) in interplanetary space (from 18 R_s to 240 R_s). Simulation results show that the main body of SMFSis typically with a strong magnetic field, low β, high μp, μk, low temperature and low density, but high temperature and density existing in the front and rear of the structure; expansion of SMFSresults in the saw-tooth profile of radial velocity; expansion velocity of SMFSobviously depends on the strength of magnetic field; there is almost no relation between propagation velocity of the structure center and the strength of magnetic field when SMFSis motionless relative to the inner boundary; the s ruoture can intensify (weaken) the compression to the plasma in the front (rear) of the structure when SMFSmoves relating to the inner boundary. The expansion of SMFScan generate a typical profile of magnetic cloud.

WAVE-PARTICLE MOMENTUM EXCHANGE RATE FROM ELECTROSTATIC INSTABILITY IN THE PLASMA SHEET BOUNDARY LAYER

Zhou Guocheng, Zhu Lian-fang

1993, 13(3): 174-179. doi: 10.11728/cjss1993.03.174

Abstract(1970) PDF 363KB(644)

Abstract:
The second-order theory of ion beam-density gradient drift instabilities on the outer edge of the inhomogeneous plasma sheet boundary layer (PSBL) are presented in this paper. The calculations for the second-order momentum exchange rate show that the field-aligned momentum for the cold and warm beam ions in the model may be decreased by electrostatic waves which result from ion beam-density gradient drift instabilities. These results are very helpful in understanding the isotropization and thermalization of the plasma on the outer edge of the PSBL.

ON THE IRREGULARITIES OF EQUATORIAL SPREAD F (Ⅱ)

Wu Ying, Wang Jing-fang, Liang Bai-xian

1993, 13(3): 180-189. doi: 10.11728/cjss1993.03.180

Abstract(1957) PDF 617KB(898)

Abstract:
Two models describing the small-scale nonlinear phenomena of the equatorial F-layer at night are derived from electron fluid equations and kinetic description of ions. Alarge variety of solutions, such as dipole vortices, solkons and soliton chains, are obtained from the models They can be used to explain the various small-scale irregularities existing in equatorial spread F.

THE COUPLING BETWEEN ATMOSPHERIC WAVES AND ELECTRON DENSITY PERTURBATIONS

Tu Jian-nan

1993, 13(3): 190-195. doi: 10.11728/cjss1993.03.190

Abstract(1840) PDF 413KB(1049)

Abstract:
From the atmospheric fluid equations and two-fluid equations of ionospheric plasmas coupled with each other, the coupling dispersion relation of atmospheric gravity waves and electron density perturbations in equatorial Fregion is derived and the resonant interaction between these two modes in different mediums is analyzed theoretically. The discussion shows that the gravity wave can transfer part of its energy to charged particles by resonance coupling mechanism and then induce initial electron density disrnrbanc for equatorial spead F. In the process, the resonance condition and resonance coupling are significantly influenced by plasma instabilities.

SHOCK COMPRESSION CURVE OF JILIN CHONDRITE AND ITS SIGNIFICANCES

Dai Cheng-da, Wang Dao-de, Lin Wen-zhu, Jin Xiao-gang, Chen Pan-sen

1993, 13(3): 196-203. doi: 10.11728/cjss1993.03.196

Abstract(1894) PDF 559KB(1111)

Abstract:
Shock compression curve of Jilin chcmdrite with H-chondrite representives is measured by the electrical pin technique on the dynamic high pressure device equipped with a two-stage light gas gun. The curve shows that under>70GPa shock pressure Jilin chondrite transforms into the high pressure phase which zero-pressure density is 4.425 g/cm³, and the zero-pressure density of silicates is 4.068 g/cm³. This study results of shock compression pro-perities of H-cho’ndrites are consistent with the planetesimal accumulation model of the Earth formation (1ABiron meteorite + Hgroup chondrite). In addition, minimum impact velocities for important shock features in main types of meteorites are calculated by the impedance-matching principle in term of shock compression curves of meteorites or analogue materials, and then the dynamic condition on formations of shock features in meteorites and the impact environment of their parent bodies are discussed.

THE EFFECTS OF CHINESE HERB MEDICINE IN IMPROVING MORPHOLOGICAL STRUCTURE OF INTERNAL ORGANS IN SIMULATED WEIGHTLESSNESS RABBIT

Shen Xian-yun, Wang Yu-qing, Xiang Qiu-lu, Meng Jing-rui

1993, 13(3): 204-208. doi: 10.11728/cjss1993.03.204

Abstract(2152) PDF 382KB(1022)

Abstract:
The purpose of this experiment is to investigate whether some kind of Chinese herb medicine has the effect of decreasing the morphological changes of internal organs in rabbit under simulated WL. 53 rabbits are exposed to headdown suspension to simulate the influence of WL. The rabbits are divided into four groups: contrast group, head-down suspension group, Chuan-Qipng group and Dan-Huang group (Chuan-Qiong, Dan-Huang, names of Chinese medicine). Morphological changes of the brain, lungs, heart, kidney, aorta and so-leus muscle are observed. The result showes the Chuan-Qiong (CQ) or Dan-Huang mixture (DH) has effects of improving the conditions of circulation and structure of organs in SWLrabbits, and the effect of DHseem to be better than that of CQ. So the Chinese herb medicine may have a good prospect of being used in space flight.

A NEW METHOD OF MILISECOND-RESOLUTION DATA——THE ANALYSIS OF SOLAR DATA AT2.84 GHz ON MAY16, 1991

Zheng Le-ping, Liu Yu-ying

1993, 13(3): 209-214. doi: 10.11728/cjss1993.03.209

Abstract(2062) PDF 378KB(941)

Abstract:
This paper compared the smoothed averages of solar ms-resolution data with s-resolution data of the burst at 2.84 GHz on May 16, 1991 and found that the two kinds of data are not self-consistent, neither in calibration nor trend of burst fluxes. In this paper, using above method, the data of May 16, 1991 are processed and found the ms-resolution records can be reduced to the s-resolution records. The makes it clear that the data with various time constants from the improved receiver in 1990 are self-consistent.In this paper, a band-pass filter is used to separate the components of rapid fluctuations with various time scales from ms-resolution data of solar bursts. Although the components of rapid fluctuations with the time scale lower than 0.1s have not been found in data of May 16, 1991; above method is very useful to examine and processing data in future observations.

A DISCUSSION ON A NEW METHOD OF THE SOLAR PROTON FLARE WARNING

Wang Shi-jin, Lin Hua-an

1993, 13(3): 215-223. doi: 10.11728/cjss1993.03.215

Abstract(1983) PDF 533KB(825)

Abstract:
In this paper, the observational data of hard X-ray emission of solar proton and non-proton flares proveded by SMMsatellite during 21st solar cycle are analyzed. The results show that for proton flares the correlativities among the hard X-ray parameters, such as peak. flux, integral flux, ratio of peak flux to the increasing time, maximum X-ray photon energy and duration time, are very notable, shile they are ambiguous for non-proton flares. Based on the different behaviours between proton and non-proton flares, as a testing it is tried to warn solar proton events (1980.2-1986.2) by using the method of the fuzzy clustering analysis. The testing results show that this new method is very feasible. Accurate warning rate is 88.5%, false warning rate is 53.1%.

THE IONOSPHERIC RESPONSE TO THE MAGNETIC STORM ON JULY 8TH 1958

Jiang He-rong, Yang Mei-hua, Liu Yu-ling, Wang Huan-fang

1993, 13(3): 224-230. doi: 10.11728/cjss1993.03.224

Abstract(2079) PDF 502KB(904)

Abstract:
In this paper, using the data of 52 ionosonde stations distributed in the world, the developments of the ionospheric disturbance during the magnetic storm on July 8, 1958 and the propagation direction and velocity of this disturbance are inrestegated. The following conclusions are obtained.1. The ionospheric disturbance for each sector started from polar regions. Besides this characteristics, after the beginning of the magnetic storm, there is a disturbance center in the equator area of American sector. The disturbance in the nearbgy regions are controlled by it.2. The disturbance developed from high latitude to low latitude.3. The frontal surface of the disturbance is almost perpendicular to geomagnetic field lines. It means the disturbance propagates along magnetic lines. The propagation velocity for the disturbance is between 105and 600 m/s.

DIURNAL AND SEASONAL VARIATIONS OF THE LF SKY-WAVE PROPAGATION OVER LONG DISTANCE

Tian Yu-shu

1993, 13(3): 231-238. doi: 10.11728/cjss1993.03.231

Abstract(2289) PDF 527KB(662)

Abstract:
This paper presents primary results observed on diurnal and seasonal variations of the 100 kHz Loran-Cfirst-hop sky-wave over a west-east path of about 2880 km from Xinxiang for the time period June 1987-September 1988, and emphatically analysed solar control me-charisms of sky-wave amplitude and phase variations, sky-wave amplitudt drop and interferences.Results of analysis indicate that the relations of the sky-wave amplitude and phase with solar zenith angle x during the daytime are approximately proportional to cos x and P. lnsecx respectively.Successive analysis and explanation for results of observations imply that during the daytime the lower region of the low ionosphere composes of two layers: an upper one (D-layer) which causes the deviative reflection of a sky-wave and a lower one (C-layer) which overlaps partly with an upper layer and causes the non-deviative obsorption of a sky-wave.And it is also found that the C-layer is markedly more intense in summer and autumn than in winter and spring, and that besides the non-deviative obsorption it has caused the marked partial reflection of a sky-wave in summer and autumn

THE RADIATION DOSE AND ITS PREDICTION IN THE CABIN OF MANNED SPACECRAFTS

Qi Zhang-nian, Chen Mei, Li Xiang-gao

1993, 13(3): 239-244. doi: 10.11728/cjss1993.03.239

Abstract(2078) PDF 497KB(874)

Abstract:
The mathematical model for prediction of radiation dose in the cabin of manned spacecrafts on near-earth orbit is complied according to 95 set LiFmeasured data and their flight orbital parameters. The model indicates that the dose level in cabin is affected mainly by orbit altitude, with a quadratic curve in this model. The solar flare activity is another factor and the effect of orbit inclination seems no importance. The predicted safe flight time is given by this model, and the radiation protection is also discussed in this paper.