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The model of low temperature radiant floor system and room are establiashed in this paper, the Thermal in ANSYS is applied to simulate the temperature dsitrubution between different floor layers and at differnt room level under differnt water temperature of the inlet and outlet and the piping spacing. The conclusion is that the room environment and condition is optimal if the heating ssyetm is designed with piping clearnce at 100 to 250mm and water supply tempeatue from 40 to 45 °C.

In the next generation of heterogeneous wireless network environment, to meet the network requirements of diverse services ,we propose a vertical handoff decision algorithm based on QoS evaluation that refine the handover unit to services. The proposed algorithm consider the needs of the services、 network conditions、 user preferences and other factors, and makes Analytic Hierarchy Process (AHP) and cost function combine to choose the target network that is best meet the requirements of services . Comparing with the vertical handoff decision based on RSS, simulation results show that the proposed method can take full account of the different QoS requirements of various services types to choose the appropriate network, and would not cause performance degradation.

Solar Salt is the best hot transfer medium molten salt of solar thermal power generation.In order to study the hot corrosion behavior of four graphite is in the molten Solar Salt.The graphite immersed equipped with molten salt crucible placed in a muffle furnace,each period of time remove the sample and weight the weight gain until the sample is completely destroyed.The destruction forming of graphite is analyzed by XRD, SEM and OP.The study found that the order of hot resistant corrosion of molten Solar Salt of four graphite materials are the fine structuregraphite,isostatic graphite,9# graphite and cold pressing graphite.The principal factors can affect hot corrosion resistant of graphite is the graphitization degree. The hot corrosion resistance of the graphite can be enhanced with the increase of graphitization degree.

One isolate of mycorrhizal fungi from the roots of wild plant, in this experiment, the growth rate and dry weight of mycelium used as measurement index, PDMA medium is found suitable as basic medium for this strain after 4 kinds of medium are preliminarily screened. Using microbial dilution plate counting cultivation method, the rhizosphere soil microbial quantity were analyzed in a blueberry short-term pot experiment. Results indicate that the number of microbial physiological groups in rhizosphere soil under different varieties of different treatments were significantly differences,and bacteria were dominant,followed by actinomycetes,and fungi were the least.

This paper proposes a remote monitoring system that consists of three clients and servers. A web server is adopted to supply a remote visiting interface for browsers from Internet. A video server is installed to capture the live streaming video, and broadcast it to video clients that are embedded in browsers. More ever, a TCP DAQ (Data Acquisition) server is designed to acquire data from sensors, and then transmit them to VI (Virtual Instrument) clients that are also embedded in browsers. To support VI clients that are designed by different languages, such as C++, Flex or HTML5, multiple protocols are integrated in the TCP DAQ server. Through identifying the type of virtual instrument client that is connected to it, the TCP DAQ server can select a protocol automatically.

Co-based high temperature alloys have been widely used in aeronautics and astronautics industry, because of its high strength at high temperature, excellent resistance of hot corrosion and oxidation. Unlike the traditional Co-based superalloys, strengthened by solution and carbide strengthening, the novel Co-Al-W superalloys are strengthened by a ternary compound with the Ll2 structure γ-Co3(Al,W). And the novel Co-Al-W superalloys showing high-temperature strength greater than those of conventional nickel-base superalloys, will become the candidates for next-generation high-temperature materials. We research alloying element Ta effect on microstructure of Co-Al-W superalloys by vacuum arc melting. Compare with the microstructure before and after adding alloying element Ta of Co-Al-W superalloy, we find that most of Ta element distributed in the γ-Co substrate phase, stabilizing and reinforcement the γ phase.

Combining with the advantages of the piezoelectric material, positive and negative torque actuator using dual piezoelectric-stack is developed for vibration active control of annular flexible structure in this paper. The working principle of the actuator is described, and the output performance of the actuator is tested in this paper. Also the actuator is applied successfully to the vibration active control of annular flexible structure.

For the dynamic modelling and simulation of electromechanical coupling systems, the corresponding vector bond graph procedure is proposed. Based on the kinematic constraint relations of rigid body, the vector bond graph procedure for modelling spacial multibody systems with revolute joint is described. For the difficulties brought by differential causality in the system automatic modeling and simulation, the effective decoupling method is proposed. As a result, the unified modelling and simulation for electromechanical systems are realized, its validity is illustrated by the robot system driven by electrical motors.

According space track-service technology，the dynamic virtual prototype has be built，using ADAMS-Viewsoftware for the rods and cones type docking mechanism. And focusing on the key influencing parameters we have finished dynamics analysis.

In order to increase the reliability and efficiency of the dynamic analysis of complex robot systems, the corresponding vector bond graph procedure is proposed. Based on the kinematic constraint condition, the vector bond graph procedure for modeling robot systems with cylindrical joint is described. For the difficulties brought by differential causality in the system automatic modeling and simulation, the effective decoupling method is proposed. As a result, the unified modeling and simulation for robot systems are realized, its validity is illustrated by the spatial robot system with five degrees of freedom.

After dissolve PVDF in DMF, porous PVDF beads were prepared by water assistant. The porous beads were better crystallized and possessed greater relative surface than ordinary PVDF. The results suggested that the relative surface of PVDF reach 6.53m2/g while the dripping speed was 0.95ml/min. The material could rise to the modulator to fabricate nanometer fiber polymers.

The mathematical model on acid-base titration was established by using analytical chemistry theory; therefore the author designed a program to solve the model by using of Visual Basic language. The program can not only calculate the pH Value of the acid-base titration solution, choose the appropriate indicator, calculate the endpoint error and judge the feasibility of the titration, but also can draw the curve of the acid-base titration.

In order to study the effect of tantalum to the microstructure and phase composition of Co-8.8Al-9.8W-XTa (X=0,2,at%) superalloy. The Co-8.8Al-9.8W-XTa (X=0,2) supperalloy used pure element powder, according to the ratio of different atomic percentage composition to make ingredients. It is mixed by planetary ball mill, pressed into blocks after the melting shape. Vacuum induction melting process was prepared by melting, after grinding, polishing, and after a volume of 5% perchloric acid and 95% of the electrolytic etching solution prepared in ethanol corrosion observed after analysis of the microstructure and phase composition by OM and XRD analysis. It can be found that the 9.8W and 2Ta alloy were mainly composed of rich γ-Co matrix of austenite precipitation of γ phase and coherent with matrix of the L12 structure of γ′-Co3(Al,W) phase. In addition, Ta element has effect on grain refinement and the number of γ′-Co3(Al,W) phase refines grain.

Cobalt-based Stellite 6 alloy rely primarily on carbides, forming in the Co matrix and grain boundaries, for their strength and the distribution, size and shape of carbides depend on processing conditions. We have employed microstructure and corrosion behavior of Stellite 6 by combustion synthesis and vacuum induction melting with scanning electron microscopy, electron probe microscopy analysis. The results show that there are significant uniformity on microstructure and corrosion behavior of Stellite 6 by different techniques. The combustion synthesis has more advantages over conventional manufacturing process for Stellite 6.

Fixed-bed column studies for the removal of Ag(Ⅰ) and Cr(Ⅲ) from individual aqueous solutions using puffed rice husk were investigated in this work. The experiments were conducted to study the effect of important column parameters such as bed height, feed flow rate and feed initial concentration of solution. It was found that increasing bed depth yielded longer service time while increase in influent concentration and flow rate resulted in faster breakthrough. Bed Depth Service Time (BDST) model was applied to analyze the experimental data and the model parameters were evaluated. Good agreement of the experimental breakthrough curves with the model predictions was observed.

In this paper, laser cladding was deposited Co-9Al-7.5W superalloy on 304 austenite stainless steel plate and cladding layer shape, dilution, Vickers hardness, microstructure and distribution of alloying elements were investigated. It was found that laser cladding layer has the characteristics of large dilution rate, fine microstructure, narrow heat-affected zone (HAZ), narrow alloy elements segregation, high Vickers hardness, high contents of alloying elements and low contents of Fe in the cladding layers.

The article puts forward a method for calculating the arresting force of carrier aircraft in the case the aircraft meets the cable off-center and the aircraft motion is unsymmetrical. The condition under which the hook will or will not slip on the cable is considered. Based on a great deal of numerical results, the article analyzed the impact of unsymmetrical motion and off-center on landing dynamics of carrier aircraft.