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Thin wall was formed by multi-layer overlapping laser cladding. The results showed that the surface of thin wall presents granular. Laser remelting could obviously improve the surface finish of the thin wall because of the melt of small granules. Match between the laser beam and the powder stream is very important and directly affects the forming quality. The microstructure of the thin wall presented obviously and continuously grown dendrite. Individual layers form metallurgic bonding and ensure whole properties of the cladding thin wall.

According to the different reaction mode, the combustion synthesis sintering can be divided into two kinds of mode: the self-propagating by heating ignition such as laser (SHS, Self-propagating High-temperature Synthesis) and whole explosion in the vacuum furnace (TE, Thermal Explosion). In this experiment, the Ni-Al powder compact is synthesized completely to nickel aluminides by SHS and TE. The experimental parameters controlling the ignition step such as material parameter and adiabatic temperature were calculated as a function of initial stoichiometry. Al mole ratio in initial powder mixture was varied from Ni: Al=3:1 to Ni: Al=1:1 for controlling adiabatic temperature.

In this paper, iron tower component is taken as measuring object, online automatic detection is aimed to achieve, and the system frame is constructed to carry out electro-optic automatic detection of the iron tower component, then designing of large size examination machine will be accomplished, which will set up the foundation of theory and the technology for large size examination machine development.

In acid fracturing, excessive acid leakoff is thought to be the main reason that limits fracture propagation and live acid penetration distance, so its very important to do research about acid leak-off on naturally fractured carbonates. we developed a new model in this paper to simulate acid leakoff into a naturally fractured carbonates gas reservoir during acid fracturing. Our model incorporates the acid-rock reaction on the fractured surfaces. Given the information of the Puguang gas reservoir, the model predicts acid filtration and leakoff rate over time. In this study, we found that acid leak-off mechanism in naturally fractured carbonates is much different from that in reservoirs without natural fractures. The leakoff volume is several times of nonreactive acid. Since the acid widened natural fractures, leakoff velocity increase with time firstly , then decrease. While the leakoff velocity of the nonreactive fluid decrease sustained. We also analyze other sensitivity parameters of the acid leakoff. In this model, we explain the acid leakoff mechanism in naturally fractured carbonates, and provide a more accurate calculating of fluid loss.

phase diagram is known as Maps of Materials Science. However, the existing precious metal phase diagrams are far from able to meet the needs of the development of the precious metal materials science and technology. In this paper, the recent research achievements of Au-Ag-Y ternary phase diagram by experimental method and Au-Pd-Zr ternary phase diagram by multi-phase equilibrium thermodynamic calculation software were introduced.

A 6061 aluminium rectangular tube extrusion using porthole dies was simulated by finite element software DEFORM-3D. The speed, stress, strain and temperature in the extrusion was given and analyzed. Using the original porthole die, the speed at the bearing entrance is not uniform. Bearing length at the rectangular corners should be increased. The stress, strain and temperature near the bearing are the largest, so the region of the die should be treated and enhanced.

Based on the physical models of PROSPECT, SAIL and porosity model, hyperspectral data and canopy coverage data of different combined scenes were simulated. According to the simulated data, we chose four sensitive bands and four sensitive vegetation indexes highly correlated to vegetation canopy coverage, and analyzed the correlation between sensitive bands, sensitive vegetation indexes and canopy coverage. Then we built a regression model of canopy coverage with EVI highly correlated with canopy coverage. At last, we verified this model by experimental data from ground measurement experiment. It shows that there is a high correlation between EVI and canopy coverage and the regression model built by EVI can produce an effective result and the RMSE is less than 0.09.

In the present numerical study, we consider a low-Prandtl liquid metal heated by Joule effect in a rectangular cavity with an aspect ratio of 2. The direct current provides heat to the process medium by a pair of plate electrodes, located at the cavity sidewalls. The simulations have been carried out using finite volume method for fixed values of the Prandtl number, Pr=0.01, and of the Rayleigh number, Ra=1.5×104, while the Hartmann number, Ha=1410, Comparison between the original noise-free data and cleaned data is explored. More precisely, accurate performances predicted using removing noise from numerical simulation data is obtained to define the inherently complicated nature of the competition of buoyancy with electromagnetic body forces.

Transverse thickness difference is a key index of plate shape for electrical steel product. This paper analyzed and optimized original automatic control system for transverse thickness difference of MH UCMW rolling mill. By adding Multi-points assessment in edge drop region, steep drop width is reduced, and system yield is improved; By optimizing rigid control strategy into flexible control strategy, using three stands control instead of two stands, and rationally allocating each stand load for edge drop control, transverse thickness difference quality level is improved, and rolling stability is promoted. Based on control system optimization, control ability for transverse thickness difference is significantly improved, head-tail ultra gauge length is shortened from 110 meter to 50 meter, and transverse thickness difference high-quality ratio is improved from 35% to 87%.

Taking MH UCMW cold tandem mill as research object, broken edge wave generating mechanism and characteristics were analyzed which caused by edge drop control. Based on original control strategy, an automatic edge wave control model was developed, and edge drop control strategy was optimized. Effect of taper work roll shifting and taper shape on broken edge wave were analyzed by actual rolling data. Results show that broken edge wave decreases with effective contact depth increasing of taper work roller and strip. Optimized control system application eliminate broken edge wave, and improve automatic shape control accuracy.

Rigid polyurethane foam has many advantages such as low thermal conductivity, good thermal insulation, good antisepsis ability, non-toxic, and light quality. Based on the above reasons, this paper systematically summarized the processing technologies of rigid polyurethane foam, and research progress of its reinforced technology by inorganic materials was briefly discussed.

Research progress of preparation methods of nanofibers was briefly reviewed and discussed based on the classification of two component composite method, template synthesis method, polymer limited domain synthesis method, and electrospinning method. Research orientations related to preparation methods of nanofibers were also proposed.

Cutting pick is a kind of widely-used consumptive mining tool. The traditional producing technics of cutting pick body is foundry, or machining after roughly forging, or machining directly from metal bar. By former technics, the property of products is poor, and by latter, the material availability is low and the cost is high. The patent technology for cutting pick body warm extrusion introduced in this paper can overcome all the disadvantages mentioned above. In this paper, by analyzing the characteristic of cutting pick body warm extrusion, adopting the principle of power balance to solve the approximate solution of strain forces, the approximate calculating formulas of extruding power are deduced. The main factors affecting on extrusion force are determined theoretically. This research can be used as basis to design tooling and choose proper equipment for this new technology.

The bionic surfaces with convex domes were designed based on the bionic tribology. Using the self-made test-bed for measuring the plane friction coefficient, the friction coefficients between the samples and the belt were measured. The belt’s type used for tests is NN-100 and its number of plies is three, as a fixed contact surface. The samples consisted of the convex dome with spherical crown, convex cylinder and smooth rubber surface as a comparative sample as well. The influences of the press, temperature and loading time on the friction performance of the bionic surface with convex dome were analyzed by the friction coefficient in the different conditions. Compared with the measuring result of the smooth rubber surface, the increasing-friction effect of the bionic surface is analyzed and the influences on the bionic surface from the factors mentioned above are examined if they are the same with those on the smooth surface. According to the test results, the influences on the friction performance from the shape, dimension and hardness of the convex dome are discussed and the increasing-friction mechanism is analyzed.

Springback is the prominent problem in bending forming of sheet metal, which is difficult to control accurately, especially for the complex shaped bending parts. The change of blank-holder force will cause significant changes of bending springback amount. The theoretical analytical model of cap-shape parts bending, which takes into account of the harden ability, anisotropy and elastic deformation of material, is proposed in this paper based on the plane deformation assumption and the bending theory of sheet metal, the cap-shape parts bending of wide sheet is analyzed theoretically, the approximate calculation relational expression is derived between the blank-holder force and springback angle, and the influence of blank-holder force on springback is discussed. In the same conditions, the springback result deduced from theoretical formula is basically consistent with numerical simulation and experiment result.

A series of novel pyridazinone derivatives was designed and synthesized. Insecticide activities of 7 pyridazinone derivatives were evaluated. The Preliminary bioassy test showed that compounds exhibited mild activity or moderate activity against Oriental armyworm at 200mg L-1

The research of cutting force and vibration has been gaining significant attention to improve machining efficiency and tool life in processing metals. In this paper, the plunge milling system is reduced to 3-DOF vibration system, and dynamical theoretical model and instantaneous undeformed chip thickness models are established based on dividing cutter tooth into finite number of small differential elements in the radial direction and discrete time domain. Based on regenerative chatter theory, the cutting force and vibration can be simulated by numerical algorithm. Compared the simulation results with experiments data, the milling force and vibration have a good agreement, which testify the correction of those models

Inorganic nanofibers are characterized by small size effect, quantum size effect and surface effect. Inorganic nanofibers and polymer form polymer and inorganic nanocomposites, which has become an active research area and showed good development and application prospects. As a typical type of inorganic fibrous minerals, sepiolite group mineral fibrous materials can not maximize nano-effect due to small particle size, high specific surface area, high surface energy and easy reunion of inorganic nanofibers. Based on the above reasons, this paper systematically summarizes the processing technologies of sepiolite group mineral fibrous materials, and proposes the suitable processing technology of batch production of sepiolite group mineral fibrous materials at low cost based on the analysis.

Based on the analysis of the working principle and structure characteristics of helical milling unit, the prototype’s three-dimensional model was built, the prototype’s finite element modal analysis was conducted, and the first 6 natural frequencies and their mode shapes were obtained. The finite element model is experimentally validated by comparing finite element and experimental modal’s parameters. This paper investigates the dynamic properties of prototype, and provides theoretical references for the subsequent dynamic analysis and structural optimization.

The current research on the porthole-die aluminium alloy extrusion is presented here. The empirical method and simulation method are analyzed. Particularly, the Lagrangian Finite Element Method(FEM), Eulerian Finite Volume Method(FVM) and Arbitrary-Lagrangian Eulerian(ALE) algorithm are compared. The development of the porthole-die aluminium is educed.

In the process of development in the oilfield, scale has been produced. Thus laboratory-scale deposition tests have been used to understand scale deposition mechanism. The process, mechanism and the main type of the scale in Asp flooding well of the forth plant of the Daqing oilfield were analyzed. To investigate the concentration change of the ions in the formation water with the injection of the Asp complex liquid and the scaling mechanism in the process of Asp flooding the core dissolution test was carried. Some of the scale samples were characterized by scanning electron microscope (SEM), and the results of the element analysis were investigated.

The micro textures in the foot surface of the animals such as locust and tree frog have been analyzed with the bionic tribology and several kinds of the convex-hull-typed bionic driving drums are designed. According to the friction mechanism of the rubber material and the simulation results by the software ANSYS, the increasing friction mechanism of the convex-hull-typed bionic driving drum is analyzed. When the convex-hull-typed bionic driving drum contacts with the rubber belt, besides the sliding friction force, the friction force between them also includes the additional resistance resulted from the inlaying ‘meshing effect’ between the convex hulls and the rubber belt. The convex hulls on the surface diminish the contact area, so does the sliding friction force. Therefore, only if the additional resistance greater than the decrease of the sliding friction force, the convex-hull-typed bionic surface can increase the friction force. The dynamic tension measuring system of the belt conveyor is designed and manufactured to measure the friction coefficient between the belt and the driving drum. The experiment results prove that the convex-hull-typed bionic driving drums that meet the certain conditions have the increasing friction effect. The research achievement can be used in many situations which need increase the friction force.

The new-type networking and intelligent safety bed aiming at quakeproof and anti-violence is studied and designed. This Safety Bed includes the high precision seismograph, the pneumatic system, the Double-wing-typed Closed Mechanism, controlling system and so on. It can protect user from the danger from the earthquake and violence. The networking control system designed can interface with the Internet which combines the manufacturer-user service system with the Safety Bed in the world to offer the service online. The correlation technique can be applied in the seismic monitoring at home and hotel, in the home intelligent early-warning, in the intelligent anti-violence, and so on.

LiFePO4powders were synthesized from LiOH•H2O, FeSO4•7H2O, and H3PO4 via the hydrothermal process at 200。C . The particle sizes, morphology and electrochemical performance of the as-synthesized LiFePO4particles varied from the pH value, reaction time and solution concentration of the precursor. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvaostdtic charge-discharge tests. The results indicated that the samples with carbon coating after reacting at pH value of 9 for 4h exhibited good rate capability, which had small particle size and plate-like morphology.

In the process of oil production and processing, there will be produced large amounts of oily sludge, which is one of the important factors that have adverse effects on oil field and surrounding environmental quality. This paper reviewed the current treatment methods of oily sludge, and prospected the future research and development tendency.

This paper focuses on the stiffness and damping characteristic of hybrid magnetic bearing for high-speed electrical machine. Firstly, it analyzes the structure and working principle of hybrid magnetic bearing, according to the bearing’s magnetic circuit properties, it deduces the equation of the bearing’s magnetic force with displacement and current. Then, combining with the controller parameters it deduces the stiffness and damping equation of magnetic bearing. At last it simulates the stiffness and damping characteristic curve, and the obtained simulation results can give theoretical support for rotor dynamic analysis and modal analysis.

For high-speed permanent magnet (PM) electrical machine, the PM material has very small tensile stress, and it can’t withstand the huge centrifugal force. So, a high-strength sleeve with interference fit is necessary to protect the PM. This paper mainly analyzes the strength of rotor sleeve and PM. It deduces the theoretical calculation method of the strength according to Lame equation, and it also analyzes the stress of sleeve and PM by ANSYS Workbench. The result show that the theoretical calculation value is closely to the ANSYS result, and it can meet the requirements of protecting the permanent magnet in high rotation speed.

A new 4 DOF parallel mechanism with serial input limb is presented ——2UPS-RPU parallel mechanism, the limb with serial input is a less contrained active branched-chain,the number of its DOF is less than six,that is to say,the limbs not only transmitting driving force but also constraint force at the same time.Compared with traditional parallel mechanisms,the mechanism with serial input has greater number of DOF than the number of limbs and don’t lose the property of parallel mechanism. The inverse solutions to positions of the mechanism are modeled by inverse kinematic analysis in this paper, then the constraint conditions are established according to factors influencing the workspace of parallel mechanism,such as the limits of the hinge angle and the parallel link length.The workspace of 2UPS-RPU parallel mechanism can be obtained by using exetreme-boundary numerical algorithm in Matlab,the volume of workspace can be quantified by means of computation,and analyzing the impact of rod length ,circumradius of moving and fixed platform and motion pair rotation angle on the workspace.

In order to study the influence of convex hull density on friction contact of bionic surface, we observed the 3-D structure of locust, tree frog and grasshopper with the 3-D microscope system, the experiments show that there convex hulls(diameters are 4um-6um)on the unsmoothed surface of feet pads; based on that structure the paper designs four kinds of unsmoothed bionic surfaces with different densities(center distances are 2R, 3R, 4R and 5R), the four contact models built by ANSYS are solved at the same loads and constraint condition, results indicate that the elastic deformation on top surface of convex hull is minimum (about 1.000mm) and the maximum (2.135 mm) appears on the midpoint of neighboring convex hulls, and the elastic deformation would increase with the decreasing of convex hulls’ density, big and small density would decrease the contact pressure also. We conclude bionic unsmoothed surface with appropriate density would put up satisfying contact performances and the surface3（center distances is 4R）we designed provides a good reference for bionic surface design and fabricating.

Q235D is one kind of peritectic steel, so the casting production inevitably encounter the universality defects of peritectic steel casting. The bloom(250mm×280mm) of Q235D is produced by 60t consteel EBT—LF(VD)—CC process at Xining Special Steel. The main problem in the production is the transverse corner crack, finally lead to occur the cracks and “triangular gaps” at surface of round bar（Φ130mm）after rolled. In order to eliminate the defects caused by transverse corner crack of bloom, the morphology and microstructure and principle of crack formation is researched. The results showed that the crack is caused by stress along the intergranular, and no obvious segregation and particles founded around the defects. The following parameters on the continuous casting process are optimized: steel composition, superheat, the choice of a various slag, the cooling water of different section, casting speed and the electromagnetic stirring parameters. Finally the cracking defects of the bloom is eliminated, and the quality of the bar is optimized.

Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to predict separation percent(SP) of NaCl solution as a function of concentration, temperature, flow rate and voltage. Besides, in the MATLAB, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically. We obtained fitted values of SP by ANFIS. Then, we studied these influencing factors on fitted values of SP. Finally, we draw a conclusion that SP is in direct proportion to temperature and voltage, but in inverse proportion to concentration and flow rate.

Fuzzy system is known to predict model in the electrodialysis process. This paper aimed to study fitting effect by ANFIS in a laboratory scale ED cell. Separation percent of NaCl solution is mainly as a function of concentration, temperature, flow rate and voltage. Besides, ANFIS(Adaptive Neuro-Fuzzy Inference System) based on Sugeno fuzzy model, its structure was similar to neural network and could generate fuzzy rules automatically, using the error back propagation algorithm and least square method to adjust the parameters of fuzzy inference system. We obtained fitted values of separation percent by ANFIS. Separation percent from experiments compared with the fitted values of separation percent. The result is shown that the correlation coefficient is 0.988. Therefore, it is verified as a good performance in the electrodialysis process.

In order to change the dendritic grain structure of Al-Cu alloy to equaxed grain, the effects of electromagnetic stirring on the microstructure of an Al-Cu alloy were investigated. The results show that the positive and negative stirring has the best stirring effects at the same condition. It is apparent that the morphology of α-Al is closely related with the comprehensive interactions between stirring strength and stirring time.

In order to offer theory base for the widely use of Roadbood EN-1 soil firming agent in road base, triaxial shearing tests are performed on road base consolidated with Roadbood EN-1 soil firming agent, cement and lime to analyze its mechanical properties. Stress-straining curve, peak strength, remnant strength, elastic modulus and shearing strength of road base consolidated with Roadbood EN-1 soil firming agent, cement and lime under different ambient pressures are measured through triaxial shearing test. The conclusions are peak strength, remnant strength and peak straining have straight line relationship with ambient pressure. Its destruction procedure can be explained with impairment. The stress-strain relation curve also indicated that Duncan-Chang Model could not be applied to road base consolidated with Roadbood EN-1 soil firming agent, cement and lime, while the modified Saenz Formula could be used to describe the stress-strain relation of it,and good agreement was obtained.

According to the various components will play a different role in the system's reliability evolution, software architecture reliability is analyzed by architecture-based software reliability model in this paper. At the same time, the method of contribution analysis of the component in the process of reliability-oriented software evolution is proposed. The method shows that which component of the overall system plays an important or crucial role in the process of reliability evolution. The efficiency of the software evolution can be improved through contribution analysis of the component in the process of reliability-oriented software evolution.

In this paper,the different form of polyacrylamide and the production of polyacrylamide at home and abroad are summarized.The history, development and the tendency of polyacrylamide around the world are presented.

Polyaspartic acid (PASP) was prepared by the means of polymerizing maleic anhydride and ammonia solution. In order to find optimal condition of synthesizing PASP, we made a set of experiments on proportion of material, temperature and time of polymerization in the single condition, and compared PASP with other scale inhibitors about the performance of scale inhibition and biodegradation. The results show: the optimal proportion of material is 1:1.1, the temperature of polymerization is 160°C, and the time of polymerization is 1h. Under above condition, we synthetized the PASP its inhibiting efficiency can reach over 95%, and biodegradation rate reaches 70%.

Oily sludge is the solid being discarded or the oily sludge material. Oily sludge mainly comes from human activities in Petroleum Production and sales. In the development and utilization of oil and manufacture of petroleum products, would inevitably product oily waste. In order to achieve thermo chemistry to wash oily sludge and reclaim oil resources from oily sludge, analyzing component of landing oil sludge with Gravimetric Method, the result of analysis is necessary parameter that determine oily sludge cleaning process. The optimal mixing time, washing temperature, liquid/solid mass rate were determined based upon residual oil rate.

During oil production from several wells in Daqing, significant productivity decline was noticed. One of the reasons behind the productivity decline might be scale precipitation. The corrosion is very serious for scaling of the fifth injection wells. It brings enormous damage to oilfield and seriously influences the oilfield production and development. Based on the research of scaling of three different sections of injection wells, we clear the distribution of injection wells scaled and the source of injection water. Choose the representative scaling wells of three blocks and injection water sample, use modern instrument analysis method to analysis the composition of water and scale sample. According to the data analysis, to certain the components of the sample scale, put forward the main form of scaling mechanism, and provide a dependable basis for making effective measures of scale removal and prevention.