活动星系核与类星体中致密天体的形成与并合：伽玛爆发与引力辐射

频繁的超新星爆发可用以解释活动星系核与类星体的超高金属丰度。星团中的恒星与吸积盘相互作用导致致密天体中子星和黑洞的形成率很高,这些致密天体与红巨星很容易形成双星系统,而后形成（ＮＳ／ＢＨ,ＮＳ／ＢＨ） 双星由于引力辐射最终导致并合而形成伽玛射线爆发。我们估计了伽玛射线爆的爆发频率,发现与观测相符。     

超新星遗迹X射线研究

在此介绍我们基于ＡＳＣＡ 和ＲＯＳＡＴ 等Ｘ 射线天文卫星,对３Ｃ３９７ 、Ｇ３２７ ．１１ ．１ 、Ｇ２１ ．５０ ．９ 和ＲＸＪ１７１３ ．７３９４６ 等超新星遗迹的物理特性进行的分析,简要地讨论了３Ｃ３９７ 的非平衡电离双热分量和双极泡结构以及Ｇ３２７ ．１１ ．１ 和Ｇ２１ ．５０ ．９ 中隐匿脉冲星的性质,并提出ＲＸＪ１７１３ ．７３９４６ 和ＡＤ３９３ 客星之间可能的关系。     

Soil water dye tracing,with special reference to the use of rhodamine WT,lissamine FF and amino G acid

Three fluorescent dyes (Rhodamine WT, Lissamine FF and Amino G Acid) are compared for use in soil water tracing. Severe limitations are evident, but practical applications are possible. Background fluorescence, adsorption, desorption, pH and other non-adsorptive effects are reviewed in the contexts of soil column work and field tracing of soil water. Lissamine FF and Amino G Acid are to be preferred for soil column work because of their lower adsorption; Rhodamine WT exhibits higher adsorption but is useful in field situations where organic fluorescence backgrounds are high. Semi-quantitative work may be undertaken in soil columns once a priming and flushing procedure has been adopted.     

海洋沉积物动力学的示踪物方法

本文的论题是示踪物方法在海洋物源追踪和沉积物输运率计算中的应用 ,以及示踪物方法的普适性理论框架。定量的物源追踪需要适当的示踪标记和物质混合模型 ,有必要根据沉积动力过程的研究来确定示踪标记的变换函数 ,从而将改进的示踪标记用于混合模型分析。人工示踪物实验的现有方法以空间积分法最为常用 ,其关键是示踪物质心运动和沉积物活动层的界定。天然示踪物的质心位置是无法定义的 ,因此不能借用传统人工示踪物方法来估算物质输运率 ;在某些特殊情形下 ,可以利用天然示踪物的质量守衡原理来获得物质输运信息。今后 ,以示踪物质的连续方程为基础 ,有可能建立一种同时适用于人工和天然示踪物的普适理论框架。其中需解决的问题包括示踪物与现场物质的差异、沉积速率和活动层厚度的时间尺度、沉积物扩散过程等。     

Ionospheric measurements of relative coronal brightness during the total solar eclipses of 11 August, 1999 and 9 July, 1945

Swept-frequency (1/10 MHz) ionosonde measurements were made at Helston, Cornwall (50°06N, 5°18W) during the total solar eclipse on August 11, 1999. Soundings were made every three minutes. We present a method for estimating the percentage of the ionising solar radiation which remains unobscured at any time during the eclipse by comparing the variation of the ionospheric E-layer with the behaviour of the layer during a control day. Application to the ionosonde date for 11 August, 1999, shows that the flux of solar ionising radiation fell to a minimum of 25±2% of the value before and after the eclipse. For comparison, the same technique was also applied to measurements made during the total solar eclipse of 9 July, 1945, at Sörmjöle (63°68N, 20°20E) and yielded a corresponding minimum of 16 ± 2%. Therefore the method can detect variations in the fraction of solar emissions that originate from the unobscured corona and chromosphere. We discuss the differences between these two eclipses in terms of the nature of the eclipse, short-term fluctuations, the sunspot cycle and the recently-discovered long-term change in the coronal magnetic field.     

几种静校正方法的比较研究

为解决近地表速度异常和地形起伏引起的静校正问题,已出现了多种静校正方法,这常常使资料处理人员无所适从。这里从众多的静校正方法中选择了三个具有代表性的,在生产中用得较多的方法(折射静校正、无射线追踪层析静校正、非线性层析静校正),从方法原理、方法特点、实际应用效果等方面进行了比较研究,最后给出了针对不同目标选择适当静校正方法的建议,以帮助资料处理人员在实际资料处理中,有针对性地选择静校正方法,快速有效地完成资料处理任务,提高处理质量。     

多项式的井间地震速度场反演方法

基于契比雪夫多项式的旅行时反演方法,不需进行入射角扫描,首先用多项式表示出深度和慢度,计算出从源点到接收点的旅行时间,通过与实际时间的误差修改模型参数,经过反复迭代,最终得到地下复杂构造的界面形态和速度变化。与网格化速度反演方法相比,计算的未知数少,对初始地质模型的依赖性小。模型试算表明,在初始地质模型与实际地质模型差别较大时,仍能取得比较好的反演结果。     

江西德兴斑岩铜矿成矿物质来源同位素示踪

德兴斑岩铜矿铜厂和富家坞矿区样品中碳、硅、铜等同位素的分析研究表明:含矿菱铁矿中碳同位素δ13CPDB值近似于原始岩浆初始值;代表成矿同期样品的硅同位素组成δ30Si分布范围与该区岩浆岩的硅同位素组成相近,个别样品偏离代表岩浆岩的δ30Si分布范围;岩体中65Cu的早成矿阶段团块状黄铜矿铜同位素组成相对较高,而晚成矿阶段脉状黄铜矿铜同位素组成相对较低。结合前人硫同位素数据可知:德兴铜矿成矿物质主要来自花岗闪长斑岩岩体,少部分来自围岩。     

线性体图像自动矢量化算法研究

依据线图的结构特点,首先提取节点信息快速抓住图像的总体拓扑结构,然后以节点信息指导进行矢量跟踪,能够有效解决复杂的交叉点问题,提高矢量化的效率和精度。基于节点信息指导和对不同连通体分类跟踪的方法避免了跟踪起始点选取的随意性和跟踪方向选取的盲目性,并具有抗噪性好和适应性强的特点。     

Errors due to the anisotropic-common-ray approximation of the coupling ray theory

The common-ray approximation eliminates problems with ray tracing through S-wave singularities and also considerably simplifies the numerical algorithm of the coupling ray theory for S waves, but may introduce errors in travel times due to the perturbation from the common reference ray. These travel-time errors can deteriorate the coupling-ray-theory solution at high frequencies. It is thus of principal importance for numerical applications to estimate the errors due to the common-ray approximation applied. The anisotropic-common-ray approximation of the coupling ray theory is more accurate than the isotropic-common-ray approximation. We derive the equations for estimating the travel-time errors due to the anisotropic-common-ray (and also isotropic-common-ray) approximation of the coupling ray theory. The errors of the common-ray approximations are calculated along the anisotropic common rays in smooth velocity models without interfaces. The derivation is based on the general equations for the second-order perturbations of travel time.