空间科学学报

1988 Vol. 8, No. 3

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A Self-adjointness Condition for the Operator F in the Energy Principle

Hu You-qiu

1988, 8(3): 161-167. doi: 10.11728/cjss1988.03.161

Abstract(1730) PDF 526KB(983)

Abstract:
This paper presents a self-adjointness condition for the operator F appearing in the Beinstein energy integral and explains the difference between this condition and the conservation condition of the system.Conventional solid-wall boundary conditions can maintain the conservation of a system and thereby guarentee the self-adjointness of the operator F,whereas conditions on moving boundaries can only achieve the self-adjointness of the operator F at most.While stipulating the boundary conditions,special attentions must be paid not only to achieving the self-adjointness of the operator F so as to make the energy principle valid,but also to the physical basis of the boundary conditions so as to make the stability judgement meaningful.

Beam-Cyclotron Instabilities by Moderately Relativistic Electron Ring-Beam

Zhou Guo-cheng

1988, 8(3): 168-176. doi: 10.11728/cjss1988.03.168

Abstract(1766) PDF 712KB(952)

Abstract:
High frequency (ω>ω_e) beam-cyclotron instabilities excited by moderately Jelativistic electron ring-beam are studied in regions where the electron plasma fre-quency wc is much higher than the electron cyclotron frequency Q_e(i.e.ω_e²>>M_e²).It is found that the beam-cyclotron modes of energetic electrons are unstable in the cases of N²cos²θ<1 and N²cos²θ>and stable in the case of N²cos²θ=1,where N is the refractive index and d is the propagation angle.When the frequency of beam-cyclotron mode is nearly one of the eigenmodes of cold background plasma,i.e.to ≈ω_e,the growth rate is the largest.Numerical solutions of the dispersion equation are also presented and discussed in this paper.

The Influence of Dawn-Dusk Electric Field on the Triggering of Magnetospheric Substorm

Mu Jian-lin, Pu Zu-yin, Fang Zheng-zhi

1988, 8(3): 177-184. doi: 10.11728/cjss1988.03.177

Abstract(1743) PDF 560KB(898)

Abstract:
By studying the ewwect of Exit drift on the tearing mode instability,the influence of dawn-dusk electric field on the triggering of magnetospheric substorm is investigated.The tearing mode equation including the E×B drift term is derived and solved with a step-like electric current distribution.The Calculations show that the critical thickness of the current sheet allowed for the triggering of the tearing mode instability and the growth rate of long wave-length modes both increase with increasing dawn-dusk eleatric field.Therefore as dawn-dusk electric field is enhanced,the magnetospheric substorms are easily generated and the energy stored in the plasma sheet can quickly be released as well.

A Model Study of the Time Delay of the Response of the Ionospheric E-field to the Magnetospheric Activity

Shen Chang-shou

1988, 8(3): 185-193. doi: 10.11728/cjss1988.03.185

Abstract(1700) PDF 727KB(887)

Abstract:
Several forms of the driven potential φ₀(t) on ionospheric polar boundary were used to calculate the time evolution of the region 2 field-aligned current J_∥² and the ionospheric electric field E (t).Calculation indicates that when φ₀ increases first,and decreases then,similar tendency is shown in variation of ](2) and E in high-latitudinal ionosphere,though reach their maximum a bit later;so when the driven potential begins reducing,the J_∥² and E,however,continue their enhancing.The time delay of J_∥² and that of E are both related to the relaxation time of the variation of J_∥² when φ₀(t) is a step function,but the delay of ?is a bit shorter.They also depend on the form of the φ₀(t).The retardation time can be longer than 1 hour when φ₀(t) decreases slowly after a sudden increasing.This result is coordinated by the data observed during strong magnetic storms.The response of E-field in the middle latitude ionosphere is somehow different.It increases when φ₀(t) increases,and decreases asφ₀(t) decreases.The evolution of the J_∥² and E is also controlled by the ionospheric conductivity.

A Study of Radio Inversive Method of Ionospheric Isorefractive Index Surface Motion Velocity Profile

Hou Jie-chang, Wu Qing-lin

1988, 8(3): 194-201. doi: 10.11728/cjss1988.03.194

Abstract(1739) PDF 641KB(944)

Abstract:
In the first part of this paper,three inversive methods for the ionospheric isorefactive index surface motion velocity profile are discussed summarily.In the second part of this paper,the theoretical value of Dopple shift of echoes for a given electron density distribution profile model (Chapman Model) and a given velocity profile of isorefractive index surface are calculated.Then,the velocity profiles are calculated with three inversive methods to examine the method itself respectively.The results show the method using O-wave and X-wave's Doppler shift data simultanosuly is the best moreover the responsibility of the disturbance in the space where there is no trace in the dopplerionogram (below h_min) for the Doppler shift of echoes can be calculated with this method.

A Study of the Ungrouped Iron Meteorite and Its Silicate Inclusion

Zong Pu-he

1988, 8(3): 202-208. doi: 10.11728/cjss1988.03.202

Abstract(2054) PDF 2904KB(855)

Abstract:
In this paper,the Guin was chemically,mineralogically and petrologically investigated and the results show that the Guin is an ungrouped iron containing 45μg/g Ga and 186μg/g Ge.It is a coarse octahedrite with unusually high Ni (92.5mg/g).The Guin contains 6±3 vol.% silicate inclusions.The Guin inclusion is similar in composition to some melt glasses in ordinary chondrites produced in situ by shock compression.As a result,we suggest that the Guin assemblage formed by impact-melting on a chondrite parent body.

Effects on Development of Artemia Eggs Recovered from Satellite "8785"

He Jian, Zhou Qi-Ling, Xing Guo-ren, Su Rui-zhen, Chen Qu-e

1988, 8(3): 209-214. doi: 10.11728/cjss1988.03.209

Abstract(2095) PDF 523KB(867)

Abstract:
Eggs of Chinese native brine shrimp,Arte mia solina,were simply packed in oblate plastic capsules and then carried by satellite "8785".The total dose of ionizing radiations received by the eggs during 5-day spaceflight was about 150 mrads.The flown eggs started to be incubated in artificial sea water and observed,along with ones of earth control,on 8th,21st,24th,34th and 66th days after accomplishment of the flight.Main phenomena found were as follows: (1) A significant delay of emergence and hateching occurred in flown eggs.(2) The extent of this delay appeared to have reduced gradually during prolongation of egg storage at 4℃.(3) Reduction of rates of emergence and hatching was also seen in the flown eggs,and it was going more and more serious during prolongation of the egg storage.(4) The survival curve,within 23 days,of larvae hatched from flown eggs was very similar to that of ones from earth control eggs.A "developmental barrier" and a "critical level" of agg damage were supposed in explaining the phenomena.

The Mathematical Analysis of Heart Rate Response Curve During Treadmill Exercise and Its Application

Yan Xiao-xia, Shen Xian-yun, Xu Li-hua, Zhuang Xiang-chang

1988, 8(3): 215-222. doi: 10.11728/cjss1988.03.215

Abstract(2157) PDF 653KB(1323)

Abstract:
In this paper,the dynamic change of heart rate was used to study its whole response on physical load by means of mathematical method and to evaluate the response capacity of the cardiovascular system.11 subjects (6 young physical workers and 5 middle aged mental workers) were selected for the treadmill tests under three diferent loads (submaximal,medium and light) and two different physiological functional states (before and after 20 days bed rest).By means of least square method,optimal fitting expressions of heart rate response curve were established during exercise and recovery peroid respectively.Through the study of different load and different physiological functional states,physiological meaning of each parameter in equations was established.Five independent parameters were obtained,they were selected as indicators for evaluation of the response capacity of cardiovaslular system under exercise loading and can be used to differentiate three different loads and two different physiological functional states.This study provided the scientific basis for the selection of candidates and medical monitoring as well as for the study of response characteristic of the cardiovaslular system.

Effects of Simulated Weightlessness on Rabbit's Ear Microcirculation

Shen Xian-yun, Xiang Qiu-lu, Meng Jing-rui

1988, 8(3): 223-232. doi: 10.11728/cjss1988.03.223

Abstract(1719) PDF 935KB(1187)

Abstract:
Experiments in two groups of rabbits (supine and head-down 20°) were done to observe the effects of cephalad redistribution of body fluid during simulated weightlessness on rabbit's ear microcirculation.Results showed that cephalad redistribution of body fluid can induce certain changes in microcirculation,i.e.increase of bore of capillaries and veinles,decrease of flow speed and blood pooling in veins,aggregetion of blood cells,patechae in the ears,and changes of regulative function of the microvessels during orthostasis.The indexes of blood rheology also had relative changes.The cause of certain changes were analysed,and some new ideas were postulated.A kind of specially designed rabbit cage and the method of observation of microcirculation through intact rabbit ears were also introduced.

Analysis of Morphology of the F2-layer Storm During the First Ten Days of February, 1986

Suo Yu-cheng

1988, 8(3): 233-239. doi: 10.11728/cjss1988.03.233

Abstract(1686) PDF 1177KB(698)

Abstract:
This paper presents the morphology of F₂-layer storms occurred during the first ten days of February,1986.It is concluded that during the storm time,there was the phenomenon of spread-F covering a large area,h'F was lifted,f₀F₂ exhibited,a negative main phase behavior in mid-latitude,but positive or negative main phase behavior in low latitude,the starting and ending time of main phase varies as in different places,and that the main phase lasts obviously longer in mid-latitudes than in low latitudes.It is also shown that with respect to the primary phase,the features of main phase in various areas are morphologically similar to each other on the whole.