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The paper applies the commercial software ABAQUS to establish numerical models of an original single-storey building and a reinforced building, and conducts experimental test to verify correctness of the computation models. Damages and dynamic characteristics of two kinds of models under seismic effects are studied systematically. X-direction acceleration amplitudes of the wall obviously exceeded those in Y direction. In the same horizontal direction, accelerations of the left wall obviously exceeded those of the right wall. Compared with the original model, the X-direction acceleration amplitude is decreased by 15.4 %, and the Y-direction acceleration amplitude is decreased by 49 % in the left wall of the reinforced model. As for right wall of the reinforced model, the X-direction acceleration amplitude is decreased by 30.4 %, and the Y-direction acceleration amplitude is decreased by 17.6 %. In the X direction, the power amplification factors of the reinforced model were less than those of the original model, and the value was decreased by 30 % for the power amplification factors corresponding to 1.3 g. In the Y direction, the power amplification factors of the reinforce model were less than those of the original model under different seismic effects, wherein the value of the reinforced model was decreased by 33 % for the power amplification factors corresponding to 1.3 g compared with the original model. Under the seismic effect of 0.1 g, damages took place to four wall bodies of the model at earliest, but its value was small. With increased seismic input excitation, damage degree of the wall bodies was also gradually increased. Under the seismic effect of 0.8 g, damages to four wall bodies were serious. Under seismic effect of 1.3 g, damage values of 4 wall bodies reached the maximum value 0.99, and the single-storey building will fail. Damages values of four wall bodies of the original model were relatively concentrated; while damage values of four wall bodies of the reinforced model were disperse. Under each seismic effect, the overall damage value was smaller than that of the reinforced model. This result fully indicates that reinforcement can reduce damages of wall bodies and generate anti-seismic effects.

Although supercritical CO2fracturing has incomparable advantages compared to hydraulic fracturing as a new recreating technology of shale gas reservoir, the application of this technology has been limited by the low viscosity and weak carrying capacity of proppant. It’s critical to enhance the viscosity of supercritical CO2by adding thickening agents. Thickening agents for supercritical CO2thathave been studied by researchers mainly contained polymers, small molecular compounds and surfactants. Thickening agents that match with CO2are characterized by low cohesive energy density, low polarity, high free volume and Lewis base. It’s necessary to study the interaction between thickening agents and CO2by molecular simulation to design inexpensive, green thickening agents which could increase the viscosity of supercritical CO2remarkably under low concentration.

By analyzing the working mechanism of timer of MCS-51 and waveform characteristics of the PWM pulse with dead-time, and proposed a new method of simultaneous control of two channels with dead-time PWM signal based on a single timer of MCS-51. This paper provided the programming idea and theoretical analysis, and this method has the advantages of simple structure, less occupied internal resources of the MCU, fast response, wide duty cycle range, waveform stabilization. By providing the driving signal for the experiment of drive circuit board DA962A4 for FF400R12KS4 type IGBT module, the validity and practicality of this method were examined.

With sulfur-contained oil tanks undergoing chemical corrosions, the corresponding products (i.e. rust, mainly comprising of Fe2O3, Fe3O4 and Fe (OH)3) would react with hydrogen sulfide, sulfur, mercaptan sulfur and other active sulfur contained in the oil to produce highly oxidizing iron sulfide, which is liable to cause fire and explosions upon exothermic reactions. In this paper, the corrosion induced by low-temperature wet H2S and natural oxidations of corresponding products within the sulfur-contained oil tanks are simulated. An analysis is also made on the temperature changing patterns during the sulfidation of Fe2O3, Fe3O4, Fe (OH) 3, and their mixtures as well as in the natural oxidation process of sulfide. Research results indicate that due to the strong oxidation tendency revealed by ferrous sulfide generated from reactions between Fe2O3, Fe3O4, Fe (OH) 3, and their mixtures with wet H2S under anaerobic conditions, it can react with oxygen in the natural air violently to release a lot of heat. The higher the content of Fe2O3 and Fe3O4, the greater the risk of spontaneous combustion would be. Moreover, the oxidation of iron sulfide undergoes three phases in natural environment, i.e. oxidation induction, oxidation incubation, and oxidation acceleration.

This paper designed a fpga-based ultrasonic flowmeter, and used verilog language design fpga control unit.The microcontroller was the core of the ultrasonic transceiver circuit. Peripheral circuit is designed to be simple and reliable, the fpga advantage in raising the maximum clock frequency, greatly improves the measurement accuracy of the design.

This paper analysis principle of BLBL(Bouguer-Laanbert-Beer-Law) model, and introduce SiO2 physical parameters of the simulation experiments to verify the scope of the model and the expected value of the theoretical model. The model be applicable under the low concentrations and meets unrelated conditions. The model full-scattering method in the optics methods of measurement obtained consistent with the theoretical value.

The radiant heat of the oil tank liquid combustion flame is the main reason of the fire spread between the oil tanks. In this paper,the thermal radiation characteristics of 10 million cubic meters oil tanks in Zhoushan Crude Oil Reserve Base in the pool fire environment are simulated using Fluent software.The results show that, the pool fire radiation intensity close to the ground was smaller than that in the parts over the tank mouth. The incident radiation intensity is over 200 kw/m 2 within the scope of radius 200m from the flame center. The incident radiation intensity decreased to 100 kw/m 2 in the place of 250m from the flame center radius. The radiant heat intensity was nearly 400-1000 kw/m 2 in the place of 72-152m from the flame center radius. The thermal radiation flux will lead to disastrous fire or explosion of the adjacent oil tanks.

Ultrasonic transducer is produced by piezoelectric materials, and it can detect some characteristics of a target media by transmitting a certain frequency of ultrasonic signals and receiving the signal containing information of the media. The special properties of piezoelectric ceramic determine that the ultrasonic transducer will have a widely used. This paper mainly studies the characteristics of the piezoelectric ceramic, the parameters and equivalent circuit of the transducer performance, and the liquid concentration detection with the transducer.

Describes briefly ultrasonic positioning system (UPS) and digital magnetic compass (DMC) heading measurement principle,analyzed the advantages and disadvantages of each option. To improve the accuracy of the heading measurement, As the theoretical basis of adaptive Kalman filter, designed a kind of ups and dmc integrated navigation system. Based on both real measurement data, made a simulation experiment and confirmed the feasibility of the navigation system.