沉积盆地火成构造研究综述

岩浆活动在沉积盆地中是非常广泛的.随着油气勘探领域的扩展,对沉积盆地火成岩及相关构造的研究愈加重要.沉积盆地火成构造是指在沉积盆地中由岩浆侵入或喷发作用形成的岩浆和围岩及上覆层变形构造的总和.当前,利用三维地震数据研究岩席的几何学与侵位机制取得了重要进展,开启了沉积盆地火成构造研究的新时代.三维地震分析是沉积盆地火成构...     

全球碳循环研究中的δ13C方法及其进展

随着分析技术的进步,δ13C观测在全球碳循环研究中越来越受到重视。在讨论关于碳循环中δ13C的Suess效应、分布特征和同位素分馏等基本概念的基础上,结合现有的观测事实,介绍应用δ13C辨别碳的源汇问题的方法,通过比较不同KeelingPlot方法分析该方法在研究大气CO2背景特征中的意义。着重讨论δ13C在研究大气C...     

A study of extratropical transition and re-intensification of Typhoon Mindulle (2004)

In this study,the fifth-generation Pennsylvania State University-National Center for Atmospheric Research (PSU-NCAR) Mesoscale Model (MM5) is used to simulate Typhoon Mindulle (2004) at high resolution (3-km grid size).The data from measurements show that in the upper atmosphere the existence of an upper jet is important to the transition cyclone.When Mindulle moved to the area of the upper jet entrance,where high-altitude divergence existed, the pumping of the high-altitude divergence would enhance the vertical motion and low-level cyclone convergence. The enhanced vertical motion was confirmed by the simulation results and indicated that the existence of upper divergence enhanced the vertical motion which was favorable for the maintenance of Typhoon Mindulle.The process of extratropical transition (ET) and re-intensification always accompanies the process of cold air invasion. This process enhances the baroclinicity of the atmosphere and the formation of front at high altitudes, which converts baroclinic potential energy into kinetic energy and strengthens the cyclone vortex.The distributions of equivalent potential temperature (θe) and temperature anomalies show that the warm-core of the typhoon at the tropopause aids the re-intensification of the system. As the typhoon reenters the ocean, latent heat flux (LHF) increases in the north and west and the strong reflectivity and vertical motion occur in the east and southeast,and the west.With the re-intensification of the typhoon the wind field evolves from an oval to a circle at the lower atmosphere, the area coverage by high winds increases, and the distribution of the tangential wind shows an asymmetric pattern.     

Numerical study on the bifurcation of the North Equatorial Current

A 1.5-layer reduced-gravity model forced by wind stress is used to study the bifurcations of the North Equatorial Current(NEC).The authors found that after removing the Ekman drift,the modelled circulations can serve well as a proxy of the SODA circulations on the σθ=25.0 kg m～-3 potential density surface based on available long-term reanalysis wind stress data.The modelled results show that the location of the western boundary bifurcation of the NEC depends on both zonal averaged and local zero wind stress curl latitude.The effects of the anomalous wind stress curl added in different areas are also investigated and it is found that they can change the strength of the Mindanao Eddy(ME),and then influence the interior pathway.     

Identification and characterization of 43 microsatellite markers derived from expressed sequence tags of the sea cucumber (Apostichopus japonicus)

The sea cucumber Apostichopus japonicus is a commercially and ecologically important species in China. A total of 3056 potential unigenes were generated after assembling 7597 A. japonicus expressed sequence tags (ESTs) downloaded from Gen-Bank. Two hundred and fifty microsatellite-containing ESTs (8.18%) and 299 simple sequence repeats (SSRs) were detected. The average density of SSRs was 1 per 7.403 kb of EST after redundancy elimination. Di-nucleotide repeat motifs appeared to be the most abundant type with a percentage of 69.90%. Of the 126 primer pairs designed, 90 amplified the expected products and 43 showed polymorphism in 30 individuals tested. The number of alleles per locus ranged from 2 to 26 with an average of 7.0 alleles, and the observed and expected heterozygosities varied from 0.067 to 1.000 and from 0.066 to 0.959, respectively. These new EST-derived microsatellite markers would provide sufficient polymorphism for population genetic studies and genome mapping of this sea cucumber species.     

城市空间智能计算平台研究

该文提出了空间智能平台的概念,阐述了其研究意义和内容,明确了空间智能计算平台核心计算模型的建模对象和目标。在此基础上,分析了宏观数学模型、群体行为模型两种用来构建空间活动模型的建模方法以及适用于空间活动分析的物理环境建模技术。从融合多尺度行为模型、构建城市日常生活模型、验证和校验核心模型以及平衡效率和效果4方面探讨了构建空间智能计算平台的关键技术。从实际功能看,城市空间智能平台是联系宏观复杂问题和微观机制的桥梁,是分析城市问题的工程化实验平台,具有广阔的应用前景。     

Impact of the variation of westerly jets over East Asia on precipitation of eastern China in July

The impact of the northward jump and westward movement of the East Asian westerly jet core from the western Pacific Ocean to the Qinghai-Tibet Plateau on precipitation distribution of eastern China is studied. It is concluded that on the one hand, the northward jump of the jet causes the precipitation belt to move northward from the middle and lower reaches of the Yangtze River valley and withdraw during the Mei-yu season; on the other hand, the westward movement of the jet core has no correspondence with withdrawal of the Mei-yu season. However, the earlier or later occurrence of the westward movement of the jet has an influence on the process of the rain belt moving northward than the northward jump of the jet: the rain belt moves northward from the middle-lower Yangtze River valley to the Huaihe River and then to an area between the Yellow River and Huaihe River during years when the time of the westward movement of the jet core is later than that of the northward jump of the jet and from the middle-lower Yangtze River valley to an area between the Yellow River and Huaihe River in other years. Further analysis shows that: (1) The northward jump of the jet and the westward movement of the East Asian westerly jet core causes significant variation of the general atmospheric circulation in middle latitudes and water vapor transport from the western Pacific, but not from the Bay of Bengal. (2) Impact of the northward jump and the westward movement of the East Asian westerly jet core on circulation are different, therefore, water vapor transport from the western Pacific and its impact on the rain belt are different. The earlier or later occurrence of the westward movement of the jet core than the northward jump of the jet causes the process of circulation and water vapor transport to be different which produces a different process of the rain belt moving northward.     

NNFFC-adaptive output feedback trajectory tracking control for a surface ship at high speed

An adaptive output feedback controller based on neural network feedback-feedforward compensator (NNFFC) which drives a surface ship at high speed to track a desired trajectory is designed. The tracking problem of the surface ship at low speed has been widely investigated. However, the coupling interactions among the forces from each degree of freedom (DOF) have not been considered in general. Furthermore, the influence of the hydrodynamic damping is also simplified into a linear form or neglected. On the contrary, coupling interactions and the nonlinear characteristics of the hydrodynamic damping can never be neglected in high speed maneuvering situation. For these reasons, the influence of the nonlinear hydrodynamic damping on the tracking precision is considered in this paper. Since the hydrodynamic coefficients of the surface ship at high speed are very difficult to be accurately estimated as a prior, it will be compensated by NNFFC as an unknown part of the tracking dynamics system. The stability analysis will be given by the Lyapunov theory. It indicates that the proposed control scheme can guarantee that all the signals in the closed-loop system are uniformly ultimately bounded (UUB), and numerical simulations can illustrate the excellent tracking performance of the surface ship at high speed under the proposed control scheme.     

达陕高速金竹山隧道涌水塌方的综合处治研究

在调查隧道K64 +664～ K64+ 674段涌水塌方特征的基础上,从地质结构和地层岩性分析其成因.相应地,建立综合工作程序,采用”超前双排长管棚+小导管+注浆+三台阶法施工+瓦斯监测”的综合方案.对灾害进行处治,效果明显.     

塔里木盆地上泥盆统一下石炭统东河砂岩沉积相与哈得逊油田的发现

哈得逊油田是塔里木盆地最大的整装油田之一,储量规模超过亿吨.在其发现过程中,东河砂岩的沉积相及其相变规律起了重要的指导作用.东河砂岩为晚泥盆世晚期至早石炭世早期海侵背景下沉积的一套海侵砂(砾)岩,主体为滨岸海滩相砂体,在全盆地范围内是一个明显的穿时沉积体.东河砂岩从古地貌低部位向高部位持续超覆变薄,以陆源碎屑滨岸-浅海...