叠前深度偏移中的旅行时并行计算技术

旅行时计算技术是基于波动方程叠前深度偏移方法的核心内容，射线跟踪的数值计算精度和效率直接影响着介质成像质量和实用化。基于三维射线跟踪的微变网络方法和波前重建思路，提出一种适用于三维复杂介质地震波走时的快速算法。但它所需计算量巨大。采用并行计算技术，设计出基于“任务缓冲池”的动态负载平衡策略，在现有的分布式计算机上，实现了三维射线追踪和叠前深度偏移的并行计算。     

What Did Freud Say About Persons and Relations?

History is bunk, declared Henry Ford; he wanted to sell new cars every year. For psychoanalysis history is not bunk; it is its very heart and guts. Like an individual or a nation, psychoanalysis lives its history and rediscovers it in every generation. Psychoanalytic pioneers, authors of new rallying cries and new theories, seem to think otherwise: History of psychoanalysis begins with them. The author suggests a different approach: to see the new as a historical continuity of the old. The advocates of the relational approach in psychoanalysis will be surprised to hear that Freud was a Sullivanian, even though--like the proverbial M. Jourdain who never heard the word prose--he never heard of the word interpersonal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

烟机异型件CAD/CAM系统的开发与应用

结合企业异型件CAD/CAM系统的开发与应用实际，简要说明了应用CAD/CAM技术是实现烟草机械异型件国产化的必要途径，论述了CAD/CAM系统的开发所依据的技术原理和涉及到的关键技术问题，分析了应用该系统所产生的社会经济效益．     

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将清洁燃料(天然气)的利用与环境结合起来进行研究，是当今世界的前沿科学技术。为了具体说明从天然气开采到使用整个过程中对环境产生的影响，采用生命周期分析的方法对天然气开采、运输、使用等三个阶段中所造成的废弃物排放进行了分析和计算，对整个过程中投入和产出的能量进行了计算，并对天然气合成氨、作为民用燃气、发电、热电联产等天然气利用方法进行了比较。结果表明：与煤、石油等传统能源相比，天然气在各个方面对环境的影响是最小的，是一种理想的清洁能源。     

长庆油田陕北区原油破乳剂的筛选和复配

实验考察了8种市售水溶性破乳荆对长庆油田陕北区有代表性的宝塔区、安塞和子长原油(均为低硫中间基-石蜡基原油)的脱水效果(加量100mg／L，脱水温度55℃，时间3h)。目前长庆采油一厂使用的YT-100和延炼集团使用的GT-940对这3种原油的脱水效果均较好，但对子长原油的脱水率不高，分别为69．7％和58．9％。在由所选性能较好的破乳刺组成的4种二元复配物中，GT-940 HQ96-1对3种原油的脱水效果均高于单剂，最佳配比分别为4：1，4：1，3：2；其余3种复配物则对原油有选择性，其中GT-940 YT-100相近(97．5％)；YT-100 HQ96-1仅能改善子长原油的脱水效果，配比为4：1时脱水率最高(76．4％)；SP-169 HQ96-1仅能改善宝塔区原油的脱水效果．配比3：2和2：3时脱水率最高(92．9％)。表5参6。     

Tribological behavior of PTFE nanocomposite films reinforced with carbon nanoparticles

Carbon-based nanoparticles synthesized by heat treatment of nanodiamond in the temperature range of 1000–1900 °C were added to PTFE film to investigate the structural effect of the carbon particles on the tribological properties of PTFE composite film. Carbon-based nanoparticles were prepared by milling with micron sized beads in chemically treated water before their addition to PTFE film. The wear and frictional properties of PTFE nanocomposite film were measured by the ball on plate type wear test. The wear resistance of PTFE film was found to be enhanced by the addition of 2 wt% of carbon nanoparticles. The wear coefficient of PTFE film was decreased from 16.2 to 3.5 × 10⁻⁶ mm³/N m by the addition of carbon-based nanoparticles heat-treated at 1000 °C. Increasing the heating temperature of the nanodiamonds caused the extent of aggregation and particle size to increase. The wear resistance of PTFE nanocomposite film was enhanced by the addition of nanodiamonds heat-treated at 1000 °C, but decreased when the heat treatment temperature of carbon nanoparticles was further increased. Tribological behavior of PTFE nanocomposite films depending on the types of carbon nanoparticles were explained based on the structural, physical and chemical modification of carbon nanoparticles.     

Superfluid Contributions to General Turbulence Theory

We analyse a numerical solution of a mathematical model of thermal superfluid turbulence. We elaborate on key points of the statistical phenomenology and point out their impact on fundamental issues of general turbulence theory.     

Hydrodynamics of Superfluid Bose Gases in an Optical Lattice at Finite Temperatures

Starting from an effective action for the order parameter field, we derive a coupled set of generalized hydrodynamic equations for a Bose condensate in an optical lattice at finite temperatures. Using the linearized hydrodynamic equations, we study the microscopic mechanism of the Landau instability due to the collisional damping process between the condensate and noncondensate atoms. It is shown that the Landau criterion for the stability of a superfluid in a uniform system is modified due to the presence of the periodic optical lattice potential.     

Dynamics of Vortex Lattice Formation in a Rotating Bose-Einstein Condensate with an Optical Lattice Potential

We study dynamics of quantized vortex lattice formation in a rotating Bose-Einstein condensate with a square blue-detuned optical lattice by solving the Gross-Pitaevskii equation. This dynamics depends on the depth of the optical lattice. Vortices tend to form a triangular lattice under the rotation, while an optical lattice likes to pin vortices at their peaks. Such a competition of two effects makes this system more interesting and complicated.     

Logarithmic Singularity of Specific Heat in Liquid Helium II at the λ Point

The experimental width of the second sound peak in Brillouin scattering is less than the instrumental width. It is also less than the width of the first sound peak near the λ point. The theoretical width of the second sound peak becomes infinitely large at the λ point in the traditional viewpoint. This discrepancy suggests that the second sound peak detected in Brillouin scattering is an elementary excitation. We calculate the specific heat of liquid helium near the λ point by considering the second sound peak. The calculated temperature-dependence of the specific heat has a logarithmic divergence at the λ point. Furthermore, the calculated values of the specific heat agree well with data derived from experiments.