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Carbon (C)-doped TiO2 nanospheres were produced using a solvothermal method, and then characterised with transmission electron microscopy, powder X-ray diffraction pattern and X-ray photoelectron spectroscopy. The C was doped into the TiO2 nanosphere as planned, and the photocatalytic oxidations were studied in environmental chambers under simulative conditions. C-doped TiO2 nanospheres' photocatalytic performance was evaluated by removing benzene, toluene, ethylbenzene, xylenes (BTEX) of paint thinners via the illumination of visible light. A degradation ratio of 93.4% in 90 min exhibited high photocatalytic activity.

With the development of new energy vehicles, it is necessary to develope new fast charging cathode materials for lithium ion batteries. This paper reports a simple carbon thermal reduction routine to synthesize layered LiMoO2 cathode for Li-ion batteries. Impurity-free micro-crystalline powders were synthesized by one-step method with a thermal treatment at 800°C for 5 hrs under N2 atmosphere. The structural, morphological and electrochemical properties of LiMoO2 were characterized by using X-ray diffraction pattern (XRD), scanning electronic microscopy (SEM), charge/discharge cycling and electrochemical impedance spectroscopy (EIS). The diffraction results indicate that the prepared sample has a layered hexagonal structure related to α-NaFeO2. The secondary particles are in order of 2.0 μm length on average with homogeneous distribution. The initial discharge capacity of LiMoO2 is 110.9 mAh·g-1 at 0.1 C, and the capacity can still remain 92.8 mAh·g-1 after 100 cycles. The good cycling performance and high rate discharge performance are attributed to the smaller charge-transfer resistance revealed by EIS results.

The aim of this work was to analyze the recrystallization behavior of cold rolled Aluminum/graphene composites during annealing. The Aluminum/graphene composite was cold rolled firstly, and then annealed at different temperature (250°C, 300°C, 350°C, 400°C) and for various time (1 h, 2 h, 8 h, 32 h). Full recrystallization did not occur until the annealing temperature was above 300 °C. With annealing temperature increasing from 250 to 300°C, the hardness of the composites decreased from 49.6 to 27.6 HV. Grain growth were not observed at high annealing temperature and longer annealing time, which suggested that Graphene has strong pinning effect on the grain boundary of Aluminum.

In this work, Al-Fe-(Cu) alloys for aluminum cables were designed and the related annealing behaviors were discussed in detail to help understand the influence of processing and heat treatment on the electrical conductivity and mechanical properties of the studied alloys. The interaction between different solute elements was tracked by using hardness and electrical conductivity testing. The microstructure was investigated by using Electron Backscattered Diffraction (EBSD) technique, along with Scanning Electron Microscopy with Backscattered Electron Detector (BSE). The results show that the conductivities of Al-Fe-Cu alloy increased with the elongated annealing time, and reaches its maximum at 6 h, when annealed at temperatures from 275 °C to 375 °C. The addition of Fe to Al can strengthen the alloy and decrease its conductivity slightly, while the addition of Cu will influence the alloy conductivity significantly. The morphologies of precipitates will change with different amount of alloying elements as well.

In this work, Al-Mg-Si-Cu alloys for automotive body panels were designed and the related ageing behaviours were discussed in detail to help understand natural ageing and pre-ageing, as well as their influence on the subsequent paint-bake response. The clustering behavior of these Al-Mg-Si-Cu alloys in different ageing conditions was investigated by hardness / yield strength and electrical conductivity testing. The microstructure was investigated by using Electron Backscattered Diffraction (EBSD) technique, along with Scanning Electron Microscopy with Backscattered Electron Detector (BSE). The results show that the paint bake response is strongly influenced by the pre-ageing and natural ageing conditions. Both alloys show serrated yielding in a short natural ageing condition. Immediate high-temperature pre-ageing treatments were found to give a promising hardening response during the subsequent artificial ageing/ paint baking at 170oC.

The grain refinement in a high specific strength Al-Zn-Mg-Cu casting ingot was studied by add different amount of Al-Ti-C and Al-Ti-B master alloys during casting. The optical microscopy observation shows that the grain size of ingot is greatly reduced when adding Al-Ti-B as low as 0.01 wt%. Both the average size and the size difference among samples from various locations of ingots are smaller when the alloy casted with Al-Ti-B, which indicates that Al-Ti-B is effecient for the grain refinement in the Al-Zn-Mg-Cu casting ingot.

This study based on the finite element method, the type of XB1-120-100 harmonic drive output torque and input rotational speed impact on transmission efficiency has been analyzed. The results show that the efficiency of harmonic gear drive increases with the output torque increased, and it has no relation with input rotational speed. When the output shaft takes the value of rated torque (Tout=450Nm), the transmission efficiency of harmonic gear drive obtained by the finite element numerical simulation is 87.1%. This value of transmission efficiency is quite close to the type of XB1-120-100 harmonic drive efficiency (75%-90%). The above analysis method and results have a guiding significance for the transmission design and performance analysis of harmonic gear drive.

Based on the thermodynamic calculation, the conditions of calcium treatment to sulfur gear steel are analyzed and the samples of rolled steel are studied. Results show that Calcium treatment to melting steel after RH refining can make the sulfide inclusions and calcium aluminates bind together and form the spindle shaped low melting compound inclusions. In the meanwhile, controlling of w (O) in steel below 0.0012% before calcium treatment is more beneficial to modify the Al2O3 and sulfide by the added calcium and to form the oxide-sulfide compound inclusions only if w (AlS) in steel is adjusted to 0.015%~0.025% before continuous casting. The Ca wire should also be fed at higher temperature.

The vertical fracture was asymmetrical about the wellbore or two wings of a fracture are not certainly in a line for the complex geo-stress in the possession of fracturing of the gas reservoirs. In view of the low permeability reservoir after fracturing developing the asymmetrical vertical fracture and non-coplanar fractures, based on the non-steady seepage theory, using the potential function theory, superimposition principle and numerical analysis method, a performance prediction model for the vertical fracture in low-permeability gas reservoirs was deduced with pressure drop superposition principle. The production decline laws were analyzed by practical cases. The result shows that the initial production of the vertical fracture is relatively high but soon followed by a sharp decline. Then, the production keeps in a relatively stable state and declines slowly in the middle and later. The fracture asymmetry factor has little effect on the gas well productivity. The non-coplanar angles have greater effect on the oil well productivity in the initial stage. The more the fracture length and the bigger the flow conductivity, the higher the oil well production and the faster the decline rate will be. However, the increase amplitude will be getting smaller and smaller along with the fracture length and flow conductivity.

A research has been developed for calculation models of allotypic pumping units load against a series of problems, which are ubiquitous in the oil field, such as unreasonable selection of the pumping unit type, low capacity factor of the pumping unit load, lacking of computing method of allotypic pumping unit load, etc. In the research, a calcaulation model of polished rod motion parameters has been firstly established according to the architectural feature of offset pumping units, dual horsehead pump units and tower pumping units. Then the load calculation model of allotypic pumping units were built based on the superposition method of each rod string stress. And after validating the load models in the oil field, the results have been indicated that the models have been in good agreement with the polished rod load. Therefore, the load calculation model of allotypic pumping units in this paper will be of some guidance significance to the selection of the pumping unit type and the stress check of the rod string in the oil field.

The sucker rod of artificial lift system in a deviated well is very complicated. This paper applies structural mechanics to analyze the distributed characteristics of stress along the sucker rod in a deviated well and builds a reliable model for stress calculation. Moreover, the model designs the sucker rod without neglecting the effects of the reaction forces and bending forces under the condition of 3D structure. Particularly, as for deviated wells with high kickoff point and long inclination paragraph, the model shows better calculation accuracy and reflects the actual local stresses.

The effects of well type, water extraction time and water extraction quantity on the control of bottom water coning are studied by analytical method. The results suggest that a reservoir with low vertical permeability and interlayer above the water oil contact would have good effect of water extraction and cone control. The effect of water extraction with horizontal well is better than vertical well; the earlier the water extraction is applied, the better the effect of water control is obtained; the larger the quantity of water extraction is, the more obvious is the water control effect, and water extraction time and water extraction quantity has optimal value. In addition, water extraction and cone control is not effective to all bottom water reservoirs that are developed with horizontal well. If the vertical permeability of reservoir is high and have not effective block off of interlining or interlayer above the water oil contact or the water body is giant, the water cut of horizontal well will go up rapidly and the effect of water extraction will be difficult to achieve.

The configuration diagram of wheeled vehicle was presented and the mathematical model of the important components was built according to the working principle of system. The subsystem properties of wheeled vehicle have analyzed by means of simulation method. Moreover, the climbing characteristic and anti- skidding properties of wheeled vehicle have done, the results shows that dual pump driving system is superior to a single pump driving system in terms of obstacle negotiation.

The production of a multilateral horizontal well is higher than the production of a vertical well, even than that of a unilateral horizontal well. Nonetheless, the stimulation effect is significantly influenced by the branch parameters, and the impacts of branch parameters on the productivity of a multilateral horizontal well are rather complex. The interference of the main hole with the branches is the primary factor influencing the stimulation effect of the multilateral horizontal well: the larger the angle-building rate of the branch boreholes, the better the stimulation effect. Therefore, longer branches with fewer branch number or shorter branches with more branch number can be used to optimize the stimulation effect of multilateral horizontal wells.

In the development of bottom water sandstone reservoir, the utilization of horizontal wells is economical and reliable but also can delay the bottom water coning and it has the advantages over the conventional vertical wells .The methods adopted in the past have methodological errors. This paper regards the reservoir flow and wellbore flow of horizontal well as a interactional system which considers the fluid friction, momentum change, the mixed interference of wellbore wall inflows and other complex factors and obtains Laplace space solution by using the Laplace transform to establish the coupled model of wellbore pressure drop calculation. It can provide more advanced means for reservoir engineering studies, well completion and production engineering design of horizontal wells on the conditions of bottom water reservoir.

The production of a multilateral horizontal well is higher than the production of a vertical well, even than that of a unilateral horizontal well. Nonetheless, the stimulation effect is significantly influenced by the branch parameters, and the impacts of branch parameters on the productivity of a multilateral horizontal well are rather complex. In this paper, the factors which affect the productivity of multilateral horizontal wells are preliminarily analyzed with the laboratory method of physical simulation. Then, a semi-analytical coupling model of wellbore flow and reservoir flow is built, and the multilateral horizontal wells are simulated to investigate the impacts of branch parameters on the stimulation effect of multilateral horizontal wells.

The research centers on the production process of high tensile 60Si2CrVNb spring steel for long service life with reference to the production conditions. Key points of the research lies in: long fatigue life and control techniques of non-metallic inclusions in melting process. Hot treatment process of spring steel also involves with the research, aiming to increase the strength of material by fining grain size by Nb element. The results confirms to the size of non-metallic inclusions can be controlled below 10μm with adoption of technologies of LF slag control and barium microalloy treatment in steelmaking process. The tensile strength can be over 2.0GPa and the elongation can reach up to 10% in the event that the quenching temperature is900°C and the tempering temperature is 410°C resulting obvious increase of strength and plasticity of spring steel.

As the sucker-rod pump placement depth increases, the load at the polished rod rises as well. Meanwhile, high load at the polished rod limits further increase of pump placement depth. This paper mainly analyses polished rod load on pumping system units and describes several methods to reduce beam pump load that are used in deep wells. On the basis of theoretical analyzing of three load reducing technologies such as application of compound fiberglass sucker rods, linear electric motors and rod load reducer, it was determined that using compound fiberglass rods in real practical cases shows obviously higher efficiency than other two. linear electric motors technology has advantages of being used in deep wells as well. Moreover rod load reducer shows good performance in deep wells, but because it does not possess energy conservation characteristic it may be uneconomic and less effective during production.

The tests of domestic In-Situ Combustion began in 1960s, with smaller and slower development. The technology has been further developed in recent years. There are five pilot projects, which increase more than 60,000 tons of crude oil. X block of Xinjiang Oil Field has been ignited since December of 2009. With the development of the In-situ Combustion technology, the use of analysis of produced fluids is very necessary, which provide theoretical basis for the commencement of the next steps. We can draw conclusion through the analysis of produced fluids: the success of ignition; the adequacy of combustion; reactions at high temperature or low temperature; the forward direction and location of fire front. Analysis of produced fluids for Xinjiang Oil Field determine clearly the ignition is successful and the way forward of the fire-drive front.

A production process of high tensile strength spring steel is discussed in this paper. Sufficient aluminum was added into ladle during tapping and barium alloy was used in late refining process. It was found that the refining slag with high basicity is strongly deoxidized after refining, with total oxygen content being less than 10×10-6 in billet. Thus, the oxide inclusions in the steel is finished the transformation during refining and some complex oxide inclusions are remarkably removed at steelmaking temperature. The tensile strength over 2.0GPa and the extension rate up to 10% are obtained for the spring steel after quenching temperature at 900oC and tempering at 410 oC. So, the strength and plasticity of the steel are improved obviously.

The inclusions in ultra-low oxygen spring steel during process were studied. Sufficient aluminium was used during tapping. The refining slag has high basicity and strong reducibility. The total oxygen is only 10×10-6 in billet and the oxide inclusions in the steel have finished the transformation during refining and some complex oxide inclusions are easy to remove at steelmaking temperature. Residual oxide inclusions in the steel are CaO-MgO-Al2O3 complex inclusions with a relatively lower melting point, which have a little deform-ability during hot-working and can improve the fatigue properties of high speed wheel steel effectively.

Some special freight need monitor particularly on transportation. By detecting state of cargo in time, raising the alarm and giving contingency command, the accident can be prevented effectively and the destructive power can be controlled. The framework of freight intelligent detection and contingency commanding system is proposed, which contains four sub-system, cargo identification system, cargo state detection system, cargo contingency commanding platform and cargo public data service platform. The structure and mechanism of main function of these sub-systems are analyzed based on their function.

At present the concept of instantaneous equilibrium is often adopted for simulating the wellbore pressure and temperature distribution in heavy oil wells. In this paper, the mathematical model was built and the diffusion of gas in the oil phase was researched. It proves that the non-equilibrium phenomenon is not obvious in convenient oil wells and it could be overlooked, while in heavy oil wells the non-equilibrium phenomenon is too prominent to be overlooked. Basing on the mass conservation principle, the momentum conservation principle and the energy conservation principle, the calculated model for wellbore pressure and temperature in heavy oil wells considering of the non-equilibrium effect was established. One example shows that the model can accurately reflect the flowing laws in heavy oil wells, which has a relative value for engineering.

To meet the demands of direct-drive petroleum equipment, developed a low-speed and high-torque permanent magnet synchronous motor. By analyzing and identifying the suitable key parameters such as permanent magnet structure parameters, air gap length, type and size of Stator Slot and so on, designed permanent magnet synchronous motor with the torque 10800 Nm, the rated speed 30 r/min and high efficiency and power factor. Obtained the flux density distribution situation and characteristic curves under no-load working condition through simulation and analysis. Manufactured the low-speed and high-torque permanent magnet synchronous motor and applied it to pumping unit. Test results show that this motor has many advantages such as wide range of speed regulation, small torque ripple, smooth operation and other characteristics. The Direct-drive Pumping Unit used this permanent magnet synchronous motor can save 20% energy than the beam pumping unit, so its social and economic benefits are significant.

This paper has created a rapid optimum method to design the gas lift parameters. Optimal Containment Genetic Algorithm (OMSGA) is applied in this method to optimize the parameters such as mass flow rate(Q), volume of gas injection(Qin), injection pressure(Pin), tubing header pressure(Pt), tubing inside diameter(Dt). According to practical situation of gas lift production, the gas lift efficiency (η) is selected as the objective function, the suitable fitness function and value of operators of OMSGA are given, and reasonable convergence delay-independent conditions is set. Based on the intelligence and global quick search of GA and the convergence of OMSGA, the design parameters of gas lift can be globally optimized quickly and accurately. An example is taken to prove that the application of GA in the field of gas lift production is successful. This new optimization method based on GA can provide guide for field design.

The research on the development strategies of conventional gas field is quite mature both in and abroad, but less attention has been paid on development strategies of coalbed methane reservoirs. This paper elaborates the remarkable dissimilarities of development strategies between coalbed and conventional gas, including commingled development design, reasonable dewatering rate and well pattern design. Eventually, Liulin area, in Hedong coal field located in Shanxi Province, China, was taken as an example to conduct optimum design of development strategies by numerical simulation software. All the aspects mentioned above can provide guidance to China’s CBM development.

A series of electric analogy experiments are designed based on the water and electricity similarity principle and frictional pressure drop in wellbore. The contribution of every branch of the multi-lateral well on oil production and the impacts of the number and the angle of branches on productivity has been studied. The results show that the productivity increases as the number and the angle of branch increases, but the increasing tendency slows down. The interference between the horizontal hole and the branch on the side with fewer branches is less than that of the other side. Experimental results provide the basis for optimizing morphology of the branch wells.

In-situ combustion (fire flooding) is one of important methods to improve heavy oil recovery ratio, utilizing the reservoir itself heavy component burning as dynamic displacement of crude oil, improving the crude oil character, flooding efficiency is high, applicability is extensive, and other recover techniques can not match. But the technical support is difficult and broad, and is the key in restricting the effect of in-situ combustion, especially for the effectiveness of development. With the increase of fire flooding development, flowing wells turns to artificial lifting wells, the gas production increases deeply, and the lifting technology faces a lot of new problems. Aiming at the problems of combustion in-situ, the relevant technologies were researched, then some methods and measures suiting to heavy oil fire flooding technology were proposed. And it provided reference for researching of deep heavy oil fire flooding lifting technology in the future.

Sucker rod pumping is a dominated artificial lift method for oil production engineering. In the production process, diagnosing the condition of pump using dynamometer card is vitally significant to monitor and manage the pumping system. With the ability to reflect arbitrary non-linear mappings, the BP neural network can be used in pattern recognition of the pump dynamometer card. In this paper, some key technologies of establishing reasonable neural network are introduced. The number of neurons in input layer depends on the selection of characteristic value. The number of neurons in hidden layer can be obtained by some models, optimum value will be chosen out. The number of neurons in output layer depends on the recognized behavior of pump. After the construction of neural network, the more effective and practical BP neural network will be obtained by suitable samples and appropriate training strategies.

It is well known that catalytic additives and mechanical milling are effective in improving hydrogen desorption kinetics of MgH2. In this study, the effect of catalytic additives including BaCa1-xNdxO3-δ (BCN) on the desorption behavior of MgH2 was investigated. It was found that BCN can improve the desorption kinetics, but not as effective as other known additives such as Nb2O5. The effect of milling temperature was also studied. It was found that the cryogenic milling is not as effective as room temperature milling primarily due to the inhomogeneous particle size distribution.

This paper deals with the microstructure and property of zinc based composites ZA27Six under the treatment of the sodium salt and the rare earth. The test material was prepared with pure zinc ingot (Zn≥99.99wt %) and the Al-Si matrix alloy. Basic composition of the test sample was Al (25~30 wt %), Si (2.5~6.0 wt %) and Zn for the rest. Impact toughness test, tensile test and wear test were conducted. The test results show that under the treatment of sodium the massive primary silicon crystal can transform to nodular silicon on which eutectic silicon crystal can form and grow in rod-like. It is also found that the combined effect of rare earth and sodium salt can obviously refine the silicon phase and the zinc based composites enhanced by nodular silicon has better hardness and wear- resistance.

Casting magnesium alloys are heterogeneous materials containing numerous voids. Assuming the voids are spherical, in the present investigation, the evolution equations of the growth and nucleation of the voids have been presented. Combining the evolution equation of the void growth with that of the void nucleation, the evolution rule of the voids was obtained. Based on the void evolution rule a nonclassical elastoplastic constitutive model involving void evolution was developed. The corresponding numerical algorithm and finite element procedure were developed and applied to the analyses of the elastoplastic response and the porosity of casting magnesium alloy. The calculated results show the satisfactory agreement with experiments.