The Empirical mode decomposition (EMD) has significant advantages in nonlinear and nonsteady response signal processing algorithms, but in the actual application process, the EMD existed some defects, in which the modal aliasing and false mode phenomenon is most prominent, the modal aliasing phenomenon can be simple in the 1 intrinsic mode function (IMF) containing more than one order structure of intrinsic mode components. The false mode phenomenon is the frequency component that should not be existed, which has a serious influence on the identification accuracy of structural modal parameters. To solve this problem, this paper studies the above two defects in EMD, and proposes an improved EMD algorithm which combines the fast ICA algorithm (FastICA) in frequency band filtering and independent component analysis (ICA) algorithm. The structure frequency is identified by hilbert transform (HT), and the effectiveness of the proposed algorithm is verified by the the Benchmark structure.

With the continuous development of gas transmission pipeline technology, application of computer simulation technology in the gas pipeline network is also increasing. The simulation model combined with the computer, can be effectively applied to the actual production, the true performance of the gas flow rule of gas in transmission line to ensure that natural gas pipeline reasonable optimization operation. Based on a comprehensive, systematic study of TGNET, SPS and other software ,useing the equation MBWRS equation of state the most accurate current gas properties calculation, and the fourth order RungeKutta method to solve the gas pipe network steady flow differential equations. And by means of C# software, combined with the advantages of related software, give full consideration to the initial and boundary conditions as well as the gas pipeline JouleThomson effect, etc. The simulation software is developed, and it's more suitable for compressors, pipes, valves, gas and other components of the source of arbitrary network. Compared with the TGNET software, the calculate results are reliable,and can be used as the initial value of the unsteady flow simulation,which has higher engineering application value.

The volume of fluid (VOF) model which was a multiphase flow model in ANSYS Fluent software was used to simulate the shellside boiling of helical coil heat exchanger (HCHE), the time relaxation parameter which dominated mass transfer was studied by equivalentevaporating method, and the value of time relaxation parameter was recommended as 3 s ^-1 for ethane and propane. The value of time relaxation parameter was also verified by heat transfer deviation. The equivalentevaporating method which was proposed could be used in all kinds of boiling simulations, and had good application value for mass transfer calculation.

Dynamic reliability models and failure rate models of bolted flange systems were developed, which took into account the failure dependence of components in the systems. It was proposed that the traditional static reliability models could not accurately describe the dynamic characteristics of reliability and failure rate of bolted flange systems. Moreover, the effects of failure dependence on system reliability and failure rate were analyzed via numerical examples. The results showed that the failure dependence had great influences on system reliability. Furthermore, the assumption that components in a system were independent of each other might cause large error in system reliability estimation. Traditional assumption of constant failure rate for mechanical systems might underestimate the system reliability. The increase in the number of bolts could enhance the ability of the system to resist the risk of failure.

The reliability, economy and adaptability of offshore oil and gas field development offshore are determined by the rational offshore development. Based on the evaluation model of single index, the weight of each index and rating grades are established by the fuzzy analytic hierarchy process. Then, the comprehensive evaluation model that considers reliability, adaptability and economy of offshore oil and gas fields is proposed, in order to evaluate and optimize the engineering model of offshore fields, which is essential to develop offshore field economically and reasonably. The results shows that the model is more comprehensive objective and effective, which could avoid the defects of single index evaluation and provide a more systematic evaluation method for the optimization of offshore engineering modle.

With the development of marine petroleum industry, marine risers appeared a variety of forms. Due to pipe shapes and the complex seabed terrain factors, severe slugging often happened. This special flow pattern damaged the equipment, production and so on. Therefore, the simulation and the research for the severe slug flow of the marine riser system had very important significance. The research was summarized by the domestic and foreign scholars on the severe slug flow of the multiphase flow riser system, including its research methods, mechanism and characteristic parameters and theoretical model, etc,which provided a reference for further study of severe slug flow in riser system.

Based on the aerial crossing pipeline structure was widely used in the construction of longdistance pipeline, due to the particularity of its structure, crossing structure extremely vulnerable to soil collapse and other geological disasters. The stress field variation law of the horizontal pipeline section of the crossing structure was studied by establishing the finite element model of the interaction between the buried pipeline and the soil. A detailed analysis of the stress changes in the pipeline was obtained when crossing pipeline structure used different horizontal pipeline section. The maximum stress value along with the variation of the settlement range of the horizontal pipeline was studied when the length of the horizontal pipe was 20 meters. The research showed that the range of horizontal section of crossing pipeline structure and soil sedimentation had greater impact on the stress field in the pipeline crossing the structure. 

The subject of experiment is oilsandsoil with high mechanical impurity. The study on the enhanced removal of mechanical impurities in oilsandsoil was carried out by ultrasonicsedimentation method. The effect factors including ultrasonic separation time, proportion of coking diesel oil, sedimentation time and sedimentation temperature were studied, respectively. The suitable conditions of demulsification and deimpurity in Indonesia's oilsandsoil were investigated by orthogonal experiment. The experimental results show that compared with the traditional sedimentation method, the removal rate of mechanical impurities in oilsandsoil is increased by more than 10% by ultrasonicsedimentation method. With the increase of the proportion of coking diesel oil, sedimentation time and sedimentation temperature, the proportion of mechanical impurities in oil sands decreased and the removal rate of mechanical impurities gradually increased. The proportion of coking diesel oil was the most important factor on the mechanical impurity proportion of refined oil. The optimum conditions for the removal of mechanical impurities by ultrasonicsedimentation method are as follows: the sedimentation temperature of 80 ℃, sedimentation time of 4.4 h, ultrasonic cleaning time 10.4 min and the mass proportion of coker diesel oil of 30.9%. Under the optimal conditions, the minimum mechanical impurity in the oilsandsoil was 0.26%.

Taking 3 kinds of atmospheric residue from Shengli, Zhongdong and Suizhong as raw materials and using series residue hydrotreating technology, the residual carbon and four components in raw material were analyzed in the process of removing metal, desulfurization and denitrification reactor. The results showed that the residual carbon, resin and asphaltene mass proportion of 3 kinds of atmospheric residue were decreased obviously after hydrogenation treatment with graded catalyst system. Compared with the raw oil, carbon residue and asphaltene decreased in metal removal process, saturated mass fractions in metal removal, desulfurization and denitrification reactor to generate oil increase regularly, aromatics mass fraction regularly decreased.

Cerium oxide is a kind of rare earth oxides of extensive uses. It has a wide range of applications in ultraviolet absorption, luminescent materials, catalysts and so on. Nano cerium oxide has special properties and can be widely used in various fields. This paper combined the research of preparation of cerium oxide based on domestic and international literature including hydrothermal, precipitation, solgel, microemulsion, microwave and so on, and summarized the advantages and disadvantages of various preparation methods.

        In order to effectively and rapidly develop the offshore fluvial faces oilfield, the development pattern of the oilfield is investigated from four aspects which are based on the features of geology and development for Bohai Y oilfield. The four aspects include, fine water injection to maintain formation pressure, combine and divide layer series of development by single sand body, well pattern optimization technology for single sand body and comprehensive adjustment by combining water extraction and water control. Development effects for each single development index developed at the development pattern of Bohai Y oilfield are calculated by reservoir engineering methods. Then the comprehensive development effects are evaluated. Results manifest that, development pattern of Bohai Y oilfield is suitable for most offshore fluvial faces oilfield. The development period  can effectively shorten the development period of offshore oil fields and improve the ultimate recovery of oil field by applying this development pattern.

       The aniline intercalated MoO₃ organic-inorganic hybrid compound as precursor was prepared. Then it was treated as Oxidative polymerization in air atmosphere at 120 ℃, the polyaniline intercalated MoO₃ composite was constructed. Rhodamine B (RhB) was used as the target degradation material, and the photocatalytic of MoO₃ composite was investigated The effects of light time, catalyst dosage and pH value on photocatalytic degradation efficiency were studied. The results show that the MoO₃/PANI composites have good photocatalytic degradation effect on Rhodamine B under the conditions of pH value of 1~4, catalyst mass concentration of 0.30~0.40 g/L and illumination time of 2.0 h, moreover that the highest degradation rate is up to 98.00%.

 

It is necessary to calculate natural gas thermophysical property parameters in the water power and thermodynamic calculation of pipelines. The method of solving each physical property parameter of natural gas and solving process were introduced in detail. The compression factor of nitrogen gas was obtained by using Van der Waals equation, RKS equation, P-R equation and BWRS equation respectively. It is concluded from the comparison of the experiment data that as a two-parameter cubic equation, the P-R has more accuracy than that of the Van der Waals and the RKS equation, but slightly lower accuracy than that of BWRS equation. But P-R equation has less number of parameters and is easier to compute and determine parameters. Therefore, the P-R equation gets an extensive application in the area of thermophysical property calculation.