空间科学学报

1991 Vol. 11, No. 1

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OH MASERS IN W33B

Zheng Xing-wu

1991, 11(1): 1-8. doi: 10.11728/cjss1991.01.001

Abstract(2340) PDF 474KB(1181)

Abstract:
The polarization observations are carried out towards OH masers in W33B with the ²Ⅱ_3/2, J = 3/2, F=1→1, and F = 2→2 transitions. The magnetic strength of 5 mGis inferred by the Zeeman splitting between right and left circular polarization spectra. The hydrogen density of the protostellar matter, n(H₂) =3×10⁷cm^-3, in the active massing region is estimated by considering a spherical maser with the fully saturation and the homogeneous pumping.

AN INVESTIGATION OF THE SODIUM LAYER FROM TRILI-GHTGLOW OBSERVATION WITH PHOTOMETER

Ma Yan-hua, Nan Jia-fu, Chai Jin-rong

1991, 11(1): 9-13. doi: 10.11728/cjss1991.01.009

Abstract(2496) PDF 416KB(1023)

Abstract:
The sodium column abundance and the peak density height of the twilight sodium layer are measured with a narrowband filter photometer from 19 twilightglow observations at the northern suburbs of Beijing between March 1987 and January 1990. It is shown that there are higher layers in spring and summer and lower layers in autumn and winter. The layer thickened in winter. The average height of the peak density is 85.7km for eight winter evenings. An annual variation by a factor of 7.5 in the sodium column abundance with maximum in winter is observed. The height and concentration variations of the sodium layer are triggered not only by the sodium photochemistry, but also by some dynamic processes.

CALCULATIONS AND ANALYSES OF VERTICAL GRADIENT OF THE GEOMAGNETIC FIELD IN CHINA AND ADJACENT AREAS

An Zhen-chang, Wang Yue-hua, Xu Yuan-fang

1991, 11(1): 14-23. doi: 10.11728/cjss1991.01.014

Abstract(2736) PDF 626KB(1237)

Abstract:
In this paper, based on the spherical harmonic model of the geomagnetic field, the spherical harmonic expressions of the vertical gradient of the geomagnetic field are given. The grid values of the geomagnetic field and its vertical gradient at 0.50, 100km above sea level are calculated. The contour maps of the vertical gradient of total intensity, vertical intensity, horizontal intensity and declination are drawn. The geographical distribution and change with height of the vertical gradient of the geomagnetic field are analysed.

EXPERIMENTAL INVESTIGATION OF LIQUID REORIENTATION IN SEMISPHERES UNDER MICROGRAVITY CONDITIONS

Gu Fang

1991, 11(1): 24-32. doi: 10.11728/cjss1991.01.024

Abstract(1991) PDF 1896KB(960)

Abstract:
An experimental investigation of liquid reorientation in semispherical container by means of microgravity accelerations is conducted in a drop tower. The liquid used has zero-degree-static-contact angles on the semispherical container and is exposed to an initially concave interface in a zero-g environment before thrust. The study is conducted at two initialconditions, with and without an initial pulse. Liquid reorientation is observed by means of a high-speed camera. Reorientation flow velocity and time are measured. The results of this study indicate that liquid reorientate along the container wall and the reorientation time measured is consistent with theoretical estimation.

LOCATION TECHNIQUE AND BIOLOGICAL EFFECT FOR ARTEMIA SALINA EGG HITED BY HEAVY IONS DURING SPACEFLIGHT

Meng Xiang-qin, Su Rui-zhen, Liu Cheng-xiang, Zhao Ke-jian, Zhang Zhong-lun, Chen Qu-e

1991, 11(1): 33-39. doi: 10.11728/cjss1991.01.033

Abstract(1976) PDF 1720KB(1040)

Abstract:
We designed and manufactured a biostack, monolayers of Artemia Salina eggs sandwiched between nuclear emulsions, to investigate the biological effect of single heavy ions to individual cells. It was exposed on board "8885" Chinese Satellite during eight-day flight and then after it returned to the ground it was collected. The distribution of tracks left by space heavy ions on emulsion was studed by means of image analysis instrument. And the development of Artemia Salina eggs was observed. Comparing with control group on ground, we found that the group on board have lower hatching rate and delayed developing time. Out of 90 experimental eggs only 8 eggs showed development at different levels. Among them 4 hatching eggs were not hit by the heavy ion and among the other 4 emerging eggs there were 3 eggs hit. Under the same condition hatching rate of control group on ground reached at almost 60%. These phenomena are obviously related to the action of heavy ions in space.From the results of the test we reached the following conclusion: the biosample plate-nuclear emulsion shadow location technique can give information of Artemia Salina eggs hit by heavy ions clearly and exactly. That is one of thte experimental and analysing methods useful to investigate biological effects and mechanism on heavy ion action.

THE ORBITS DISIGNING FOR INTERPLANETARY PROBES AND ARTIFICIAL PLANETARY SATELLITES

Zheng Xue-tang

1991, 11(1): 40-45. doi: 10.11728/cjss1991.01.040

Abstract(2427) PDF 412KB(1217)

Abstract:
In this paper, the dynamical model, orbital motion and mission time for interplanetary probe and artificial planetary satellite are given. The disign for orbit to cut mission time and save fuel is discussed and the stable region of artificial planetary satellite is also obtained.

CORONAL-HOLE CYCLE VARIATIONS OF BASIC HELIOSPHE-RE QUANTITIES AND CORONAL HOLE ATMOSPHERE

Zhou Ai-hua

1991, 11(1): 46-51. doi: 10.11728/cjss1991.01.046

Abstract(2401) PDF 429KB(956)

Abstract:
The distributions of. temperature T, density N and velocity V are given using the equations coupling the MHD waves with the coronal atmosphere. It is found that coronal-hole cycle variations of some basic heliospheric parameters, such as V, T and N can be explained by the decrease of the nonradial factor a of the magnetic field in the coronal hole as solar activity is decreased.

A SPECTRAL ANALYSIS OF THE SOLAR RADIO MICROWAVE BURST ON 1 APRIL 1981

Zheng Le-ping, Liu Yu-ying, Wang Jia-long

1991, 11(1): 52-58. doi: 10.11728/cjss1991.01.052

Abstract(1939) PDF 469KB(977)

Abstract:
A 4N Ha solar flare occurred on April 1, 1981, and accompanied with strong type IVradio burst. This paper analyses the radio data of the burst obtained at Beijing Observatory and Lear-month Observatory. The result shows that:1. The microwave source of the event is relatively stable, but the source at meter waves moves. There seems to be two electron populations responsible for microwave and meterwave radiations, respectively. The time difference between the microwave peaks and meterwave peaks is believed to be due to the different positions of the two kinds of sources.2. On April 1, 1981 the great microwave burst consists of three major bursts. The times of flux peaks are 0135.1 UT, 0146:1 UTand 0153.6 UT, respectively. The non-thermal electron spectral indices calculated at the high frequency end of the radio spectra show that the electron spectra become harder at peaks. For this burst, the calculated, average non-thermal electron speed is about 0.9c (c is light speed) and the magnetic field stre out 430G. Using the assumption of damping radiation of gyro-synchrotron, the calculated mean life of the non-thermal electrons is 829 second, which is consistent with the duration of the three major bursts.

AN ANALYSIS OF THE OBSERVATION OF SOLAR RADIO BURST AT THREE FREQUENCIES AT YUNNAN OBSERVATORY DURING THE SOLAR CYCLE 21

Ma Yuan, Yang Kai-ping, Luo Xian-han

1991, 11(1): 59-66. doi: 10.11728/cjss1991.01.059

Abstract(1985) PDF 441KB(886)

Abstract:
In this paper, the correlation between the duration and peak-flux-density of solar radio burst is analysed which is observed at 2902 MHz, 3653 MHz, 9375 MHz at Yunnan Observatory during the solar cycle 21, and the result shows that there is essentially a two-pronged distribution in all these three frequencies, and finally the relation between solar radio bursts and proton events is discussed.

RADIO OBSERVATION OF THE SOLAR ANNULAR ECLIPSE OF SEPTEMBER 23,1987 AT 3.2cm WAVELENGTH

Zhou Shu-rong, Qin Zhi-hai, Liu Pei, Yu Xing-feng, Jiang Shu-ying

1991, 11(1): 67-75. doi: 10.11728/cjss1991.01.067

Abstract(2320) PDF 561KB(932)

Abstract:
This paper presents the observation results of the solar annular eclipse of Sept. 23, 1987 at 3.2 cm wavelength. The data processing and the identification of S-component sources are also described. The following results are obtained:(1) The radius of the radio sun amounts to 1.09 in solar minimum year.(2) The distribution of the brightness temperature on the solar disk shows that there is an apparent brightness in the 13’4-15’9 range on the optical limb and its peak brightness amounts to 13.5 ± 5%.(3) The flux density of the quiet sun amounts to 264.8sfu.(4) Several observed solar radio sources are associated with sunspots and plages. The following parameters of these sources are obtained: angular sizes, flux densities, average brightness temperatures and heights. Average brightness temperatures of the sources are estimated approximately 3-4×10⁵K and 1.5-1.7×10⁵K respectively. Heights of the sources above the photosphere are 1-2.7 × 10⁴km.

THE NOBLE GASES AND COSMIC RAY EXPOSURE AGE FO THE NINGQIANG CHONDRITE

Wang Dao-de, Otto Eugster

1991, 11(1): 76-79. doi: 10.11728/cjss1991.01.076

Abstract(3094) PDF 262KB(685)

Abstract:
On the basis of study on petrology and chemical composition the Ningqiang chondrite is an anomalous CV3 chondrite (oxidized subgroup). It contains a high abundance of ag-gregational chondrules and a very low abundance of refractory inclusions. The isotopic abundances of the noble gases in bulk samples of the Ningqiang chondrite are measured. Ningqiang chondrite shows a cosmic ray exposure age of 42.2 ±4.0 Ma, the highest for CV3 chon-drites. The U/Th-⁴He age is 4170 ± 160 Ma whereas the ⁴⁰K-⁴⁰Ar age is 4260 ± 70 Ma which are similar to other CV3 chondrites such as Leoville.