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181.
刘晓红 《地震学报(英文版)》1996,9(2):345-349
Themanufactureofathree-dimensionaltransducerusedinlaboratoryXIAO-HONGLIU(刘晓红)(InstituteofGeophysics,StateSeismologicalBureau,... 相似文献
182.
介绍脉冲电镀在人造金刚石孕镶钻头上的应用研究,探讨脉冲电镀机理,采用正交试验法优化脉冲电镀工艺参数;研制了脉冲电镀钻头,生产钻头周期缩短了30%。在室内和野外生产试验中,发现脉冲电镀钻头较直流电镀钻头有如下优点:钻进地层适用范围广、钻进时效高。 相似文献
183.
Under normal temperature, the creep experiments with complete samples of Gabbro and Marble rocks are made under uniaxial compression.
It is found that at the instantaneous creeping stage, AE activities increase with loading; at the steady creeping stage, large
AE signals may appear at lower background of AE action, andm—value which shows the relationship between AE amplitude and frequency keeps stable on the low value or decreases; at the
accelerate creeping stage, AE activities increase andm—value decreases quickly or decreases again after recovery. These experimental results are related to the quality of the samples.
In this paper, AE activities during three stages of creeping process are connected with the seismic patterns (for exampleb—value, foreshocks). Finally, it is pointed out the possibility that the foreshock—mainshock—aftershock earthquake sequence
has been formed by the mechanism of creep fracture of crustal rocks.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 104–112, 1991.
This subject is sponsored by the Chinese Joint Seismological Science Foundation. 相似文献
184.
A lot of researches onb value have been made in seismology. Since the 1960’s Mogi, Scholz and others have studied AE of rock specimens in laboratory
and discovered that it is related to natural earthquakes. All former researchers used integral specimens to studyb value in the laboratory. However a major earthquake is usually related to a existing seismic-fault in that area. For this
reason, a series of fracture experiments with rock and glass specimens having pre-existing crack or notch is performed in
order to examine the effect of preexisting crack tob value. The experimental results show that theb value begins to decrease as soon as the initiation of the crack and finally drop to a very low value when the specimen breaks
unstably. Based on these, a brief discussion on the possible mechanism ofb value change for natural earthquakes is given.
The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,9, 393–400, 1987.
Projects sponsored by the Chinese Joint Seismological Science Foundation. 相似文献
185.
186.
植被区面积对局地气候影响的数值研究 总被引:7,自引:0,他引:7
用一个三维模式实施了5个数值试验,研究了植被覆盖与裸土之间的非均一性对局地气候的影响。结果指出:存在着一个最适宜的植被区面积S_c,当S=S_c,这种非均一性激发的上升运动最强,上升气流区的空间范围最大。 相似文献
187.
188.
189.
Stefano Casotto 《Celestial Mechanics and Dynamical Astronomy》1993,56(3):397-408
An analysis is presented of the orbital injection errors for the Lageos III satellite mission. Several methods are introduced for the solution of the Inverse Problem in the Theory of Errors. The novelty of the present approach consists in the use of the full geopotential covariance matrix in the error propagation equations. The GEM-T1 covariance matrix is used. It is found that by properly accounting for the correlation among the even zonal harmonic coefficients the acceptable error bounds increase by an order of magnitude with respect to the case when only the variances are used. The most stringent constraint, even when using the full covariance, is on inclination, whose nominal value must be realized within approximately 0.1° for the recovery of the Lense-Thirring precession to be successful at the 3% level (accounting only for injection errors). The associated tolerance in the semimajor axis is about 30 km while that in eccentricity is approximately 0.2. However, if the errors in semimajor axis and eccentricity can be kept to the routinely achievable levels respectively of 10 km and 0.004, then the tolerance in inclination can be relaxed to 0.2°. 相似文献
190.
Kinetic study of the hydrocarbon generation from Upper Paleozoic coals in Ordos Basin 总被引:6,自引:0,他引:6
When organic matter during geological processes is affected by a variety of factors such as paleotemperature, and time, complicated chemical reactions will occur, finally resulting in the generation of petroleum and natural gas. These reactions leading to… 相似文献