砂岩在西湖凹陷花港组交互式盖层中的作用初探

西湖凹陷花港组盖层具有砂泥岩交互式发育特征，而与泥岩伴生的砂岩类盖层的油气封闭作用研究较少。采用岩芯、镜下观察及压汞等分析方法，对砂泥岩交互式盖层中的砂岩特征进行了分析。结果表明，盖层中的砂岩可作为有效盖层，砂岩类盖层早期受沉积环境控制，含有较多的泥质而导致早期压实作用较强，加之晚期的黏土矿物转换及胶结物的发育，具备形成良好盖层的条件。在不同地区进行砂岩盖层有效性研究时应以沉积环境为基础，针对不同类型的砂岩进行成岩作用研究，并针对不同类型的砂岩样品进行实验分析以明确砂岩盖层的有效性。     

为什么要引入溶剂的渗透因子

阐明了引入溶剂渗透因子的必要性,较详细地介绍了两种渗透因子及它们间的关系。     

超临界流体触媒作用下石墨-金刚石转变

 研究了超临界流体CO₂在石墨-金刚石转变中的触媒作用。实验中，采用Ag₂O作为流体触媒的先驱材料，在7.7 GPa压力下，Ag₂O在1 200 ℃分解成Ag和O₂，O₂与石墨套管在高温高压下反应形成CO₂超临界流体。研究结果表明，在7.7 GPa和1 500 ℃以上温度条件下，石墨在CO₂流体触媒的作用下可转变为金刚石晶体，在1 500～1 700 ℃温度范围内合成出的金刚石具有完好的八面体形貌，与天然金刚石的生长特征非常相似。     

High pressure X-ray diffraction study of CdAl2Se4 and Raman study of AAl2Se4 (A=Hg, Zn) and CdAl2X4 (X=Se, S)

We report the results of an X-ray diffraction study of CdAl₂Se₄ and of Raman studies of HgAl₂Se₄ and ZnAl₂Se₄ at room temperature, and of CdAl₂S₄ and CdAl₂Se₄ at 80 K at high pressure. The ambient pressure phase of CdAl₂Se₄ is stable up to a pressure of 9.1 GPa above which a phase transition to a disordered rock salt phase is observed. A fit of the volume pressure data to a Birch-Murnaghan type equation of state yields a bulk modulus of 52.1 GPa. The relative volume change at the phase transition at ∼9 GPa is about 10%. The analysis of the Raman data of HgAl₂Se₄ and ZnAl₂Se₄ reveals a general trend observed for different defect chalcopyrite materials. The line widths of the Raman peaks change at intermediate pressures between 4 and 6 GPa as an indication of the pressure induced two stage order-disorder transition observed in these materials. In addition, we include results of a low temperature Raman study of CdAl₂S₄ and CdAl₂Se₄, which shows a very weak temperature dependence of the Raman-active phonon modes.     

钢板仓受风载作用的有限元分析

对高 14.76m ,直径 12m的螺旋卷边钢板筒仓在空仓风载工况下进行了有限元分析。计算结果表明 ,在风载作用下 ,仓体的强度不是主要问题 ,而仓顶开口处刚度较弱。     

The push-out region of an immersed manifold

We consider immersions: and construct a subspace of which corresponds to a set of embedded manifolds which are either parallel to f, tubes around f or, in general, partial tubes around f. This space is invariant under the action of the normal holonomy group, We investigate the case where is non-trivial and obtain some results on the number of connected components of . Received 24 March 2000.     

A Modified Quasi-Newton Method for Structured Optimization with Partial Information on the Hessian

This paper develops a modified quasi-Newton method for structured unconstrained optimization with partial information on the Hessian, based on a better approximation to the Hessian in current search direction. The new approximation is decided by both function values and gradients at the last two iterations unlike the original one which only uses the gradients at the last two iterations. The modified method owns local and superlinear convergence. Numerical experiments show that the proposed method is encouraging comparing with the methods proposed in [4] for structured unconstrained optimization Presented at the 6th International Conference on Optimization: Techniques and Applications, Ballarat, Australia, December 9–11, 2004