Applied Mechanics and Materials Vols. 190-191

Abstract: An ultrasound-assisted dispersive liquid-liquid micro-extraction method based on solidification of floating organic drop (UAE/DLLME/SFO) was established for the determination of PAHs in soils. Dichloromethane was used as solvent for the analytes in the soil by ultrasonic assistant extraction (UAE), the solvent was purified and concentrated by silica gel column chromatography and nitrogen flowing concentrator, respectively. The recoveries of the method were in the range 46.22-101.86%, and the relative standard deviations (RSD) were 3.03-7.80%. The linear range was 0.02-0.4mg/kg（0.02-0.5mg/kg）, and the limit of detection (LOD) was 0.17-29.13µg/kg. The method was applied to the real soil samples around wells of an oilfield; the relative recoveries of the ANY, ANA, FLU, PHE, ANT, FLT, PYR, BaA were 47.12-116.96%, while the recoveries of NAP, CHR, BbF, BkF, BaP, DBA, BPE, IPY were 17.75-63.29%.

Abstract: A full nitric oxide mechanism including thermal NO, prompt NO, N2O intermediate model and NO reduction model through reburning was used to calculate the NO formation during high temperature air combustion of natural gas in industrial furnace. The turbulent transportation was simulated by Reynolds stress model (RSM) and a modified Eddy-Break-Up (EBU) combustion model was applied to model the combustion process. A three-step reaction scheme of the natural gas combustion reaction was considered. Experimental data from published literature was adopted to validate the present models. Numerical results showed that thermal NO formation mechanism and reburning NO reduction mechanism were the dominant NO models. Reburning NO reduction could not be ignored. Prompt NO gave a small contribution to NO emission and the N2O intermediate model for NO formation was of little importance.

Abstract: High hydrophilic/hydrophobic contrast surfaces on polyethersulfone (PES) samples were formed by shadow mask technique in electron cyclotron resonance generated sulfur hexafluoride plasma atmosphere. The plasma-treated polymer film surface properties are characterized using contact angle measurement. The contact angle measurements clearly indicate that the unmasked areas on the polymer surfaces were hydrophobic with a large water contact angle and therefore decreased the surface wettability. The masked areas on the polymer surfaces increased surface wettability. In addition, the surface wetting property of the masked areas was found to change significantly with the plasma treatment time, the mask-to-substrate distance and the storage time after the treatment. The best water contact angle contrast obtained from the treated surfaces was larger than 100 degrees.

Abstract: In this paper，a model for working process simulation of gasoline engines was developed under transient conditions. Therefore，the working process of gasoline engines could be described on theoretical basis. The computer program was edited. The results of simulation are agreed perfectly with that of test，and can provide support for design and study of transient emissions.

Abstract: This paper presents a low cost compact solution for a Remotely Operated Vehicle (ROV) control system. Both hardware architecture and software architecture are discussed. STM32F-1 series MCUs are used for sensor data acquisition [1], output calculation and actuator control. For software, a real-time OS uC/OS-II is embedded in the MCU [2]. The whole control system has been implemented on an observation ROV HIPPO. The result of tank test shows this kind of control system has good performance on maneuverability, stability, reliability and control accuracy. Furthermore, HIPPO has successfully served as a third-party vision provider in the lake trail of another ROV.

Abstract: In this paper, a multi-sensor based suspension robot has been designed for the application of autonomous detection and surveillance. For fire fighters and rescuers, the disaster relief works are difficulty performed in the tunnels because of its constricted space. To reduce the losses of accident, the safety of tunnel should be ordinarily kept under surveillance. In the design of suspension robot, BASIC Stamp has been utilized as its control kernel and multiple sensors have been applied for detecting the emergencies. Once the surveillance center is announced of the emergencies, the fire fighters and rescuers could timely execute the saving mission.

Abstract: The paper presents a technique of combinational iron-cored primary for thrust ripple-free permanent magnet linear synchronous motor (PMLSM). Due to multiple end sides of primary iron-cores constructed, the low order harmonics of thrust ripple could be directly eliminated. At the same time, each phase of armature windings forms a circulating sequence at side edge, which enables the parameters of the armature windings to be symmetric and constant. Therefore, electromagnetic ripple caused by side effect will be directly removed. The theoretical analysis conducted reveals the basic characteristics of the proposed approach. Numeric simulation of the finite-element method and harmonic analysis verify the correctness of theoretic analysis and direct effects of the approach on eliminating thrust ripple.

Abstract: The radio frequency identification technology is a kind of emerging non-contact identification technology. In the study of radio frequency identification reader, the traditional microcontroller-based architecture can’t meet the system requirements due to the limited processing ability. In this paper, the author designs a UHF RFID reader based on the ARM processor and FPGA, compared to the microcontroller-based architecture, the reader deals faster. The reader consists of three parts, namely, the protocol processing module, the digital baseband module and the RF module.

Abstract: A forecasting speed smoothing algorithm based on inflexion velocity has been presented in this paper. According to the geometry characters of the machining trajectory, the inflexions in CNC machining tool path can be confirmed by using the designed algorithm. The line segment between each inflexion can be treated as a continuous path that can be tracked under the continuous feed rate. Moreover the maximal permitted link-up speed can be calculated through dynamic restriction equations and the real-time modification of sinusoidal acceleration can be realized by using the speed iteration algorithm. By simulation analysis, it can be revealed that both the flexibility and efficiency of the CNC machining has been improved and the impact to the machine tool has been greatly reduced.

Abstract: RFID technology has been widely used in mobile robot positioning system for its unique advantages. RFID tags store their unique positions which are placed on the ceiling or the floor. The mobile robot carries a RFID reader which reads the RFID tags to position itself. In this paper, a new method for mobile robot localization is proposed, and the equations to calculate the position of the mobile robot are given. Finally, the experiment results show that compared to conventional positioning method, the proposed method can effectively improve the positioning accuracy of the mobile robot.