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11.
中国上地幔剪切波速度结构的初步研究   总被引:13,自引:4,他引:13       下载免费PDF全文
本文通过合成SH波理论地震图的方法,利用SS-S走时和SS波波形资料,研究了我国上地幔剪切波速度结构。初步结果表明,我国大陆上地幔可以分成两个独立不同的速度结构模型:一是青藏高原;另一是中国大陆东部。两部分均存在剪切波低速层,但埋藏深度不同,高原部分是100km,东部地区是60km,两部分的差异大约在350km以下趋于消失。在405km和660km深处存在剪切波的速度间断面。400km以下青藏高原和中国大陆东部地区剪切波的速度结构与北美洲、北大西洋西部、欧洲、阿尔卑斯带地区的结构一致,说明在这几个地区上地幔剪切波速度结构的横向变化在400km以下很小。  相似文献   
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本文报道海面光谱辐射计的研制、定标和海上现场实验测量。运用一个 2 5 6元光电二极管列阵传感器件测量海面离水辐亮度和向下辐照度的光谱分布 ,可计算得出遥感反射比。该仪器所测量的数据可以用于海洋方面相关专业的科学研究 ,并给出海上实验测量数据  相似文献   
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Two CCD epochs of light minimum and a complete R light curve of SS Ari are presented. The light curve obtained in 2007 was analyzed with the 2003 version of the W-D code. It is shown that SS Ari is a shallow contact binary system with a mass ratio q=3.25 and a degree of contact factor f=9.4%(±0.8%). A period investigation based on all available data shows that there may exist two distinct solutions about the assumed third body. One, assuming eccentric orbit of the third body and constant orbital period of the eclipsing pair, results in a massive third body with M 3=1.73M and P 3=87.0 yr. On the contrary, assuming continuous period changes of the eclipsing pair the orbital period of tertiary is 37.75 yr and its mass is about 0.278M . Both of the cases suggest the presence of an unseen third component in the system.  相似文献   
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We develop a Monte Carlo technique based on L.B. Lucy's indivisible photon packets method to calculate X-ray continuum spectra of Comptonized thermal plasma in arbitrary geometry and apply it to describe the broad-band X-ray continuum of the galactic superaccreting microquasar SS433 observed by INTEGRAL . A physical model of the X-ray emitting region is proposed that includes thermal emission from the accretion disc, jets and hot corona where the photons of different origin are Comptonized. From comparison with INTEGRAL observations, we estimate physical parameters of the complex X-ray emitting region in SS433 and present model spectra for different viewing angles of the object.  相似文献   
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本文详细论述了功率谱与功率谱密度、平方和SS与平方平均值MS的适用范围及物理意义,比较深入地分析了平稳和非平稳加速度时间历程的统计特征,通过引入时域包线获取特定相位的方法,考虑了非平稳特性。本文基于非平稳时间历程,在不考虑频率非平稳性的基础上,提出了设计地震动三要素:(1)平方和SS;(2)归一化自相关函数或其对应的功率谱;(3)地震动时域包线.本文提出了在设计地震动合成中考虑超随机特性的实用方法,并指出地震动的超随机特性(即归一化功率谱的锯齿状波动部分,或归一化自相关函数的随机噪声部分)与相位的随机性是地震动随机特性的两个重要方面。本文将地震动的统计分析直接建立在非平稳时间历程的基础之上,从而避开了要对地震动进行平稳化处理的困难。这样提取出的地震动统计特征完全是以真实地震动记录为基础的。应用这些统计特征,可模拟出符合统计要求的基于非平稳时间历程的设计地震动。最后本文还讨论了工程上常用的将反应谱近似转换为功率谱的转换式的一些缺陷。  相似文献   
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We present time–resolved optical spectroscopy of the famous X-ray binary SS 433. We obtained 61 medium resolution spectra spread over three months and thus cover roughly five orbits and about half a precession phase. We used various emission lines, that we attribute to the accretion disc, to determine the radial velocities of the compact component. They are of course modulated with the orbital period but in addition show a variation of the system velocity on a longer time scale. With the present data it is not possible to determine whether this is a transient effect or a periodic variation, although we present various possible interpretations of this effect.  相似文献   
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The chemical and biological characteristics of surface waters in Jinhae Bay were investigated over four seasons to understand water quality in light of the growing industrialisation occurring within this area. Jinhae Bay includes four smaller bays: Masan; Hangam; Jindong; and Gohyun. The water quality in Jinhae Bay varied spatially and seasonally. The water quality of both Hangam Bay and Masan Bay was highly degraded, demonstrating high concentrations of ammonia, nitrate, chlorophyll a and particulate organic carbon. Contamination from sewage was the dominant cause of the water quality deterioration in these bays. Conversely, the water quality in Jindong Bay and Gohyun Bay was not as severely affected as that of the above two bays. Water quality in Jinhae Bay was particularly poor in summer when nutrient loading was highest due to the run-off associated with high precipitation. Principal component analysis indicated that nitrogen contamination was a major factor influencing the water quality of Jinhae Bay. The effective reduction in high-nitrogen discharges is essential to improve water quality in Jinghae Bay.  相似文献   
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