高温高压下海底管道水平向整体屈曲研究现状分析

海底管道水平向整体屈曲是深海油气管道安全性设计及稳定性分析的重要组成部分.伴随着全球深海油气资源的开发,海底管道水平向整体屈曲问题备受关注,近40年中取得了重要的研究进展.本文详述了海底管道水平向整体屈曲的发生机理及研究发展历程.分别从整体屈曲的理论研究、管土相互作用及管道热屈曲模型试验、整体屈曲数值模拟方法、整体屈曲防护措施及工程应用等几方面,阐述了高温高压下海底管道水平向整体屈曲的研究成果,并提出了今后的研究方向.     

第（3）类ψ－压缩映对的一个新的公共不动点定理

证明了第（3）类ψ－压缩映射对的一个新的公共不点定理,推广文献[1-3]中的相关结果。     

从社会需求谈我院高职学生的教育实习

新形势下，高等体育院校职业技术教育的实习工作存在新的问题，为进一步提高教育实习的质量，适应社会发展的需要，满足人们对健身娱乐休闲的需要，促进体育产业发展，有必要对这些问题进行理性的思考与对策研究。     

Reliability Analysis of Some Typical Repairable Systems with Arbitrary Repair-Time Distribution

In this paper, reliability of some typical non-Markov repairable systems, including series systems, m-out-of- n or majority vote systems, and n : m cross-strapping standby redundant systems with general repair-time distribution, are studied by applying the generalized Markov renewal process (GMRP). The stochastic behavior of the typical systems is analyzed here. Formulas for mean time to first system failure, MTBF, MTTR, and availability are then developed.     

Nodal quasiparticle in pseudogapped colossal magnetoresistive manganites

A characteristic feature of the copper oxide high-temperature superconductors is the dichotomy between the electronic excitations along the nodal (diagonal) and antinodal (parallel to the Cu-O bonds) directions in momentum space, generally assumed to be linked to the 'd-wave' symmetry of the superconducting state. Angle-resolved photoemission measurements in the superconducting state have revealed a quasiparticle spectrum with a d-wave gap structure that exhibits a maximum along the antinodal direction and vanishes along the nodal direction. Subsequent measurements have shown that, at low doping levels, this gap structure persists even in the high-temperature metallic state, although the nodal points of the superconducting state spread out in finite 'Fermi arcs'. This is the so-called pseudogap phase, and it has been assumed that it is closely linked to the superconducting state, either by assigning it to fluctuating superconductivity or by invoking orders which are natural competitors of d-wave superconductors. Here we report experimental evidence that a very similar pseudogap state with a nodal-antinodal dichotomous character exists in a system that is markedly different from a superconductor: the ferromagnetic metallic groundstate of the colossal magnetoresistive bilayer manganite La1.2Sr1.8Mn2O7. Our findings therefore cast doubt on the assumption that the pseudogap state in the copper oxides and the nodal-antinodal dichotomy are hallmarks of the superconductivity state.     

Expression of Aspergillus niger 9891 Endoinulinase in Pichia pastoris

An endoinulinase gene from Aspergillus niger 9891 (CGMCC0991) has been expressed in Pichia pastoris GS115 using pPIC9 vector. The recombinant endoinulinase was highly expressed and the optimization of the expression in a 7 liter of fermentor has been investigated. In fermented broth, the concentration of protein secreted is 2.15 mg/ml. The activity of endoinulinase is 1501 U/ml with sucrose as substrate and 291 U/ml with inulin as substrate, 105 and 273 times higher than that from the original strain respectively.     

Guangdong Dapeng LNG cold energy utilization-C2 ++ extraction process integration

This paper makes a study of some technical and engineering aspects by using C2+ hydrocarbon separation facility at Guangdong Dapeng LNG (GDLNG) terminal. In the C2+ hydrocarbon extraction process, the cold energy contained in LNG will be utilized. In order to ensure the optimum operating conditions of the terminal and C2+ hydrocarbon extraction facility by optimizing the current operating processes of the terminal, the C2+ hydrocarbon extraction facility construction plan is proposed. We conducted numerous calculations and simulations using such specific analysis software as PRO II. Additionally available flow data are used to verify the cyclic send-out rates from the terminal, thus establishing the current and future projected load factors. This study is intended to make sure that GDLNG can continue to supply gas via the pipeline system safely without interruptions and most significantly solves the effects of flow fluctuations at the terminal gasification send-out facility on the hydrocarbons extraction, ensuring optimum pipeline operations and ensuring safe and effective means for such C2+ hydrocarbons extraction process as well. At the same time, the terminal is also in the optimum operation condition. This is very significant to the terminal safety operation and the energy conservation and emission reduction.     

Data acquisition, analysis and applications of multi-sensor integration

This paper presents some key techniques for multisensor integration system, which is applied to the intelligent transportation system industry and surveying and mapping industry, e.g. road surface condition detection, digital map making. The techniques are synchronization control of multisensor, spacetime benchmark for sensor data, and multisensor data fusion and mining. Firstly, synchronization control of multisensor is achieved through a synchronization control system which is composed of a time synchronization controller and some synchronization subcontrollers. The time synchronization controller can receive GPS time information from GPS satellites, relative distance information from distance measuring instrument and send spacetime information to the synchronization subcontroller. The latter can work at three types of synchronization mode, i.e. active synchronization, passive synchronization and time service synchronization. Secondly, spacetime benchmark can be established based on GPS time and global reference coordinate system, and can be obtained through position and azimuth determining system and synchronization control system. Thirdly, there are many types of data fusion and mining, e.g. GPS/Gyro/DMI data fusion, data fusion between stereophotogrammetry and PADS, data fusion between laser scanner and PADS, and data fusion between CCD camera and laser scanner. Finally, all these solutions presented in paper have been applied to two areas, i.e. landborne intelligent road detection and measurement system and 3D measurement system based on unmanned helicopter. The former has equipped some highway engineering Co., Ltd. and has been successfully put into use. The latter is an ongoing research.     

Influence of the amplitude ratio between two terahertz pulses on two-dimensional spectroscopy

The influence of the amplitude ratio between the two THz pulses on two-dimension THz spectroscopy （2DTS） has been studied theoretically via a classical method in which the expressions for the second-order nonlinearity were derived using perturbation approach, and the THz pulses were not treated as a delta function. Three types of nonlinear sources i.e., anharmonicity, nonlinear damping, and nonlinear coupling, are considered in a single mode system. The simulation results demonstrated that the amplitude ratio had a notable influence on the 2DTSs, and different sources have different influences. This study is promising for guiding future experiments.     

Photocatalytic enhancement of Mg-doped ZnO nanocrystals hybridized with reduced graphene oxide sheets

Hybridization of Mg-doped ZnO and reduced graphene oxide(MZO–RGO) were synthesized through one pot reaction process. Crystallization of MZO–RGO upon thermal decomposition of the stearate precursors was investigated by X-ray diffraction technique. XRD studies point toward the particles size with 10–15 nm,which was confirmed by transmittance electronic microscopy,and also indicates that graphene oxide has been directly reduced into its reduced state graphene during the synthesis. Graphene hybridized MZO photocatalyst showed enhanced catalytic activity for the degradation of methylene blue(MB). The degree of photocatalytic activity enhancement strongly depended both on the coverage of graphene on the surface of MZO nanoparticles and the Mg doping concentration. The sample of 2 wt% graphene hybridized 5 at% Mg-doped ZnO showed the highest photocatalytic activity,which remained good photocatalytic activity after nine cycling runs.