Abstract:To reduce the size of wheel motor of micro electric cars and improve the sensitivity of parking brake systema new structure using electromagnetic clutch embedded in wheel motor to brake in lose electric is designedand the electromagnetic clutch is optimized and dynamically analyzed.Based on genetic algorithmelectromagnetic clutch structure parameters are designedand electromagnetic attraction force is optimized.Optimization results show electromagnetic attraction force increases by 27.6 N.Based on the finite element methodthe current curvesuction curve and displacement curve are analyzed.The results show electromagnetic attraction force and dynamic response time both meet the requirement of parking brake of micro electric cars.

Abstract:To investigate the work condition of the aircraft actuators in high temperatureheat transfer process of the output unit of a cycloidal reducer of the actuator is taken into account by Unigraphics NXHypermesh and ANSYS softwares based on finite element analysis(FEA).The temperature distribution of the output unit is obtained by meshing modelapplying loads and solving discrete problems.Thenthe temperature variation of the output unit is gotten by sampling and processing the data of FEA results.In the endthree main conclusions are drawn.Firstthe heat transfer process of the output units of cycloidal reducers of actuators can be analyzed by FEA efficiently.Secondthe temperature of the rudder and the design position of cycloid gears are two major factors in the operating life of reducers.Thirdthe operating life can be improved by lowering the rudder temperature and installing the cycloidal gear as far as possible away from the heat source.

Abstract:A mathematic model for filtering reducer transmission robots which have the characteristics of parameter uncertaintiesexternal disturbancestrong couplingnonlinearities and multi-variable is establishedand then an adaptive RBF networks backstepping method is proposed to control the robot.RBF is employed to approach the nonlinear item of the filtering reducer transmission robot on lineand an adaptive RBF network controller is developed based on backstepping method which effectively suppresses the effect of parameter uncertainties and external disturbance etc.It is combined with Lyapunov stabilization analytical method to demonstrate the close loop system convergence.Simulation results verify that the proposed controller not only satisfies high performance position trackingbut also has good accuracy and robustness.

Abstract:A Prüfer-coded genetic algorithm based on the decimal number of nodes is proposed and it is used to solve collaborative optimization planning of access solution of distributed generation(DG)and structure of distribution network.Using graph theory to generate theoretically feasible topology structureand the access nodes and the installed capacity of distributed generation are coded by the Prüfer number.The coding method makes the distribution network operation structure and the access solution of DG combine into the evolution problem of the same chromosomal gene.The length of the chromosome coding of this method is shorter than binary encoding.This solution takes full advantage of the Prüfer-coded to improve computational efficiency and convergence rateand makes some restrictions and improvements in some key parts of the algorithm to solve the problem illegal solution.Finallyfeasibility and superiority of the algorithm is validated by a case study.

Abstract:The safety of power system is greatly influenced by proper operation of power strapwhile reliable condition monitoring is a serious constraint to the intelligentization of power strap.In this paperthe reflective optical fiber sensor is successfully used to monitor and identify the condition of power strap.Anti-misoperation of power strap is added to traditional mistake precaution system without any changes and typical operation rules of power strap are summarized.A whole mistake precaution solution to both primary equipment and secondary equipment is obtainedand thus the online condition monitoring and anti-misoperation of power strap are realizedand the safety level of power system is improved.

Abstract:In combination with Huimin high-phosphorus iron smelted by smelting reduction and HIsmelt ironmaking technologywhich have the advantages of high efficient dephosphorizationCaO-SiO2-Al2O3-MgO-FeO-P2O5 slags with basicity R (mass ratio of CaO to SiO2)ranging from 0.8 to 1.4Al2O3 ranging from 6.4% to 15.4%P2O5 ranging from 0 to 3% and the content of MgO and FeO fixed as 4% and 6% respectivelyare studied.The slags are synthesized by reagent grade.The mineral composition and microstructure of the slags are studied with scanning electron microscope and the effects of changes in the composition of smelting reduction slags on its viscosity are studied by RTW-10 melt comprehensive physical properties measuring apparatus.Results show that the mineral structure of slags are mainly composed of melilite(gehlenite and akermanite)which is characterized by square and thick skeleton form.The viscosity decreases with the increasing of the slag basicity at fixed P2O5 or Al2O3 mass fractionincreases with the increasing of Al2O3 mass fraction at fixed slag basicity or P2O5 mass fractionand increases with the increasing of P2O5 mass fraction at fixed slag basicity or Al2O3 mass fraction.

Abstract:A 220 t/h gas boiler of some steel group is taken as the study objectand the idea of oxygen-enriched stable combustion is proposed and proved to be feasible with the furnace heat transfer model in order to make reasonable use of existing resources and improve the combustion stability of gas boiler in low load operation.Detailed analysis has been made about the effects of oxygen-enriched combustion on the flu gas temperaturecombustion stability boiler thermal efficiency and so on.The results show that the oxygen-enriched combustion technology can greatly improve the overall performance of the boiler.

Abstract:The Fick diffusion equation is widely used to describe mass transfer in a particlea droplet or a liquid layer in a chemical reactorwhere the definition domain of the diffusive equation is limitedbecause it is decided by the scale of those particles or droplets.The diffusive equation with a definition domain of certain length has no analytic solutions unless the series solution.Soto obtain approximate solutions of a diffusive equation is of theoretical and practical significance.After an assumption of constant concentration variance ratio is made and substituted for the presumption of constant concentration frequently used in kinetics of multi-phase reactiona detail process to deal with diffusion equation based on steady state approximation is givenand the approximate solutions of the diffusive equation with the second boundary condition and the third boundary condition are obtained in the meantime.The method to deal with diffusion equation by steady state approximation may be applied to many fields in engineering.

Abstract:Thiourea method can realize effective extraction and simplify the extraction process of gold and silverby utilizing thiourea solution as leaching agent and electrodepositing gold and silver from the thiourea leaching solution.Sulphuric acid solution containing Fe 3+5 g/Lthiourea(TU)50 g/L and pH=1 is used to leach goldsilver from pure goldpure silver and copper anode slim.The main thiourea complexes of silver and gold in the resulting leaching solution are ［Ag(TU)4］ +［Ag(TU)3］ +and ［Au(TU)2］ +.The cyclic voltammograms of thiourea leaching liquid shows that the initial reduction potential of Fe 3+H +［Au(TU)2］ +［Ag(TU)4］ +and ［Ag(TU)3］ +are 0.15V-0.25V-0.32V and -0.36V respectively.So gold is electrochemical reduced precipitation prior to silverthen reduced with silver togetherand in company with H +RSSR and other metallic impurities are reduced.However H2 evolution on cathode is the main reason for reducing the current efficiency.

Abstract:To solve the problem of poor prediction accuracy of GM(11)model when the data are discretebased on the sign of residual error modification value of prediction value being determined by Markvo chaina residual error modification is presented.The grey residual error GM(11)model based on Markvo is constructed through the modification of simulation value and prediction value obtained from GM(11)model.The prediction of tensile strength of LDPE greenhouse film under natural aging condition is taken as an exampleand the applicability of constructed model in the prediction of plastic aging behavior is researched.The results show that the relative error between prediction value and the actual value of tensile strength of LDPE greenhouse film after aging 18 and 21 months obtained from constructed model are 1.49% and 4.96% respectively.Prediction accuracy are higher than that(relative error are 3.40% and 6.75% respectively)obtained from GM(11)model obviously.Grey residual error GM(11)model based on Markvo needs less original data and has high prediction accuracythus it is a simple and reliable method for plastic aging behavior prediction.

Abstract:Downhole tools are one of the critical factors to guarantee the successful application of hydra-jet fracturing technology which is a new stimulation method with perforatingfracturing and hydraulic sealing.Some donwhole tools are cut open and the severe wear areas around the nozzle inlets inside them and on their surfaces are analyzed.In order to investigate the reason for the inside wearthe flow field inside the tools are numerically simulated.The results show that the splashback abrasive jet will erode the surface around the nozzles of the tool.For surface wear at different positions along the tool axisit will be more serious at the downstream than that at the upstream.At the same timeif the formation is loosethe abrasive jet with a high velocity will splash into formation and return from other existed perforationsresulting in extra wear at the surface relatively far from the nozzles or even the tubing’s surface.For the inside of the toolsthe wear at the upper area around the upstream nozzle inlet and lower area around the downstream nozzle inlet will be more obvious than that of other positions.The numerical simulation results explain this phenomenon clearly.The research provides reference for improving the downhole tool’s structure and its life.

Abstract:Nifedipine is poorly soluble in water and has low bioavailability.Microemulsionwhich is the ideal carrier of difficult soluble drugscan increase the solubility of drugs.The study prepares nifedipine into microemulsion typeand thus its solubility is increased and its bioavailability is improved to a certain extent.The formulation of nifedipine microemulsion is optimized via the pseudo-ternary phase diagram and the amount of nifedipine dissolved in different surface active agentssurfactants and oil phases.The optimized nifedipine microemulsion formulation consists of emulsifier OPanhydrous ethanolethyl oleate and water with the weight ratio of 27∶13.5∶4.5∶55.The prepared microemulsion is light yellowcleartransparent and has good mobility.When the microemulsion is diluted by waterits shape is spherical under transmission electron microscopy with an average diameter of 22.89 nm.It shows good stability after high speed centrifuging and reserved sampleand also their content and diameter have no obvious change.The nifedipine microemulsion is easy to prepare by this methodand its solubility is improved more than 700 times.

Abstract:The existing evaluation method of stratum thermal efficiency is on the basis of piston steam displacement model and ignores the influence of steam overlap.By studying the stress and seepage velocity of the steam in inverted nine-spot well patternthe overlapping degree evaluation method is obtainedconsidering different steam frontiers between the producer and the injector.The evaluation model for reservoir thermal efficiency is received on account of the study of steam overlapping degreeheat balance theory and the instantaneous heat balance expressionand solved by Laplace transformations and Stehfest numerical inverse method.The results show that in the early stages of steam injectionthe steam overlap degree is small and the steam chamber expands evenly on longitudinalso steam overlap has little influence on the thermal efficiency；in the middle and later stages of steam injectionwith the expansion of the steam chamber and the increase of steam overlap degreethe steam displaces along the topso steam overlap has severely impact on the thermal efficiency of the reservoir.

Abstract:Silicate mineral structures affect silicate bacterial growth. A study is carried out on the growth of a strain of silicate bacteria named JG02 in the media containing kaolin quartz bauxite respectively by monitoring the physical and chemistry parameters surface changes of silicate minerals during bioleaching. The results show that the strain has the similar growth curves in different media but the number of bacteria acid and polysaccharide production capacity vary greatly. The strain produces more acid polysaccharide and maximum SiO2(40.8 mg/L) in kaolin medium. The quartz’s is less. However similar changes are shown on surfaces of kaolin and quartz by infrared ray. Therefore the growth of JG-02 and mineral erosion will happen more easily on the surfaces of layered silicate minerals than the frameworks.

Abstract:In order to accurately calculate the magnetic field parameters of mine transient electromagnetic field based on the former research theory of transient electromagnetic field full-space and half-space combined with transient electromagnetic space applications in mines this article studies the relationship of transient electromagnetic field intensity and half-space transient electromagnetic field and proposes the multiple phenomenon of transient electromagnetic. Research results show that full-space transient electromagnetic field intensity and half-space transient electromagnetic field intensity has multiple phenomenon. They have 2 times relationship in the early stage and have 2.5 times relationship in the late stage. Similarly mine transient electromagnetic field intensity electric field intensity and apparent resistivity calculations also have multiple relationships. Putting forward the multiple phenomenon has important reference value in theory and practice for researching the mine transient electromagnetic field.

Abstract:To take full advantage of gangue for roadside supporting in coal mines physical properties of coal gangue are tested. The collapsed slump uniaxial compression strength and initial setting time of gangue binder backfill material with different water-cement ratios and admixture contents are researched. Experimental studies show that the best ratio of water cement coarse aggregate fine aggregate and admixtures is 1:2:5.6:1.6:0.02 for site pumping of roadside packing support. The collapsed slump 28 d uniaxial compression strength and initial setting time of gangue binder backfill material are 210 mm 20.8 MPa 224 min respectively under such ratio. It could satisfy the requirement of site supporting and the initial setting time of binder backfill material under such ratio is about 50 min shorter in site than indoor.

Abstract:To provide objective and comprehensive evaluation of surface water environmental quality for management and engineering projects a Fuzzy-AHP evaluation model is introduced. Level 1 is comprised of several current evaluation systems. On level 2 variable fuzzy set is introduced to evaluate the accurate grade. The model is applied to evaluate Jialing River (Ciqikou section) and evaluation result is grade III which is reasonable and reliable. The model is well-developed and physically grounded makes use of information of monitoring data more scientifically and comprehensively and provides an alternative evaluation method for water quality assessment.