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Fu X.,Construction Engineering Research Institute | Fu X.,National University of Defense Technology | Bai Y.,National University of Defense Technology
Proceedings - 2016 8th International Conference on Intelligent Human-Machine Systems and Cybernetics, IHMSC 2016 | Year: 2016

An autonomous-steerable-vehicle storage and retrieval system is derived from the traditional crane-based automated storage and retrieval system, performing higher space utilization than the latter and keeping high degree automation. In this system, several autonomous steerable vehicles move orderly at the same time to store or retrieve unit loads, which requires the structure of the rail network satisfying a series of safeness constraints. If some equipments of the system fail (such as rail deformed, vehicle broken down or lifter jamming), the structure of the rail network would be damaged, which leads to the operation management framework of the system cannot work. In this paper, the changes of the network due to the equipment fails of the system are analyzed, and the methods to recover the operation management framework of the system are discussed. In the methods, rebuilding the trunk rail cycle and degrading cut edge rails are employed to repair the structure of the rail network, which recover the operation management framework of the failed system, avoiding the system collapse. © 2016 IEEE.

Zhang M.,Xidian University | Yuan Z.,Xi'an Jiaotong University | Ning T.,Construction Engineering Research Institute | Song J.,Xi'an Jiaotong University | Zheng C.,Xi'an Jiaotong University
Sensors and Actuators, B: Chemical | Year: 2013

Platinum is widely used to modify TiO2 based gas sensing materials, and the promotion mechanism accompanied by praiseworthy results are discussed deeply. In this work, the growth mechanism of Pt dispersed on TiO 2 thick film surface is discussed. The surface state of Pt is studied by XRD, XPS, SEM and Kröger-Vink defect theory in depth. Results indicate that Pt is not only dispersed on TiO2 thick film surface in metallic state but also occupy the lattice of Ti vacancy and form the oxidation state Ti1-xPtxO2. A simple model is proposed to explain the growth process of Pt and Ti1-xPtxO 2. © 2012 Elsevier B.V. All rights reserved.

Zhang M.,Xidian University | Ning T.,Construction Engineering Research Institute | Zhang S.,Xidian University | Li Z.,Xidian University | And 2 more authors.
Materials Science in Semiconductor Processing | Year: 2014

In this work, gas response properties of Pd modified TiO2 sensing films are discussed when exposed to H2 and O2. TiO2 films are surface modified in PdCl2-containing solution by the dipping method and treated for different treatment times to get different surface states. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and Kröger-Vink defect theory are used to characterize the sensing films. The gas response properties indicate that the sensor response time which related to the rate of change of sensor resistance is affected by the activation energy (E). In particular, the sensor treated at 900 C for 2 h exhibits a response time of about 20-240 ms when exposed to H2 and 40-130 ms when exposed to O2 at 500-800 C. © 2013 Elsevier Ltd.All rights reserved.

Li Y.,Xi'an Jiaotong University | Zheng J.-L.,Construction Engineering Research Institute | Feng J.,Xi'an Jiaotong University | Jing X.-L.,Xi'an Jiaotong University
Chemical Papers | Year: 2013

This article provides a brief overview of recent work by the authors' group as well as related researches reported by others on controlling the morphology and exploring the formation mechanism of typical micro-/nanostructures of polyaniline (PANI) and aniline oligomers through template-free aniline chemical oxidation process. The contents are organised as follows: (i) tuning the morphology of aniline polymerisation products by employing ultrasonic irradiation, mass transfer, and pH profiles; (ii) exploring the formation mechanism of micro-/nanostructures during aniline chemical oxidation through examining the precipitation behaviours of aniline oligomers and polymers in a post-synthetic system; (iii) tailoring PANI micro-/nanostuctures into pre-designed morphology by introducing certain heterogeneous nucleation centres; (iv) application potential of PANI nanofibres in the areas of transparent conductive film, electromagnetic interference-shielding coating and graphene-based electrode materials. This short review concludes with our perspectives on the challenges faced in gaining the exact formation mechanism of PANI micro-/nanostructures and the future research possibility for morphologically precisely controlled PANI micro-/nanostructures. © 2013 Institute of Chemistry, Slovak Academy of Sciences.

Wang J.,Construction Engineering Research Institute | Wu Y.,PLA Fourth Military Medical University
Journal of Elastomers and Plastics | Year: 2014

Styrene-butadiene rubber (SBR) was reinforced with silica (SiO2) by co-coagulating process. This study investigated the SiO2 amount, stirring time and pH value affecting the SiO2 content, curing characteristics and mechanical properties of SBR. Results showed that SiO2 content and reinforcing behavior were greatly influenced by the amount of SiO2 and pH value. The torque, tensile strength and elongation at break were optimal when the mass fraction of SiO2 was 21.5 wt%, stirring time was 6 h and pH value was 6.57. The utilized efficiency of SiO2 decreased with the increasing amount of SiO2 but increased with the increasing stirring time. The optimum cure time decreased with the increasing amount of SiO2. Both tensile strength and elongation at break decreased with the increasing pH value. Scanning electron microscopy observations showed that the SiO2 nanoparticles were distributed evenly in the SBR. © The Author(s) 2012.

Ma Y.,Construction Engineering Research Institute | Chen Z.-H.,National University of Defense Technology
Ceramics International | Year: 2012

Effects of 1600°C annealing atmosphere on microstructures and mechanical properties of the C/SiC composites fabricated by PIP route were remarkable. Due to carbothermic reductions, the ratios of weight loss of the C/SiC composites were all above 7 wt% in 1 h. Consequently, the mechanical properties all had a significant drop during the first hour of annealing because of the bonding between the fibers and matrix remarkably weaken by cracks and pores. And then the flexural strengths gradually decreased with the annealing time increasing, when the flexural moduli slightly changed within the range of 44.2-49.7 GPa. However, the fracture behaviors of the C/SiC composites annealed under Ar faster became brittle than the C/SiC composites annealed under vacuum. The C/SiC composites annealed under Ar for 5 h and under vacuum for 10 h both became brittle mainly due to the sensitive to annealing of the weak carbon interphase, while the C/SiC composites annealed under Ar for 7 h became brittle mainly due to the chemical bonding between the fibers and matrix. And these phenomena were confirmed by the post densification and the stress-releasing annealing. © 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Ma Y.,Construction Engineering Research Institute | Chen Z.-H.,National University of Defense Technology
Cailiao Gongcheng/Journal of Materials Engineering | Year: 2015

Using SEM and TEM, the effect of 1800℃ annealing on microstructures and properties of 3D braided C/SiC composites was investigated under Ar, fabricated by PIP process. The results show that during 1800℃ annealing, the carbothermic reductions and Si diffusing happen at the interfaces of C/SiC composites, resulting in the chemical bonding between fibers and matrix, and fibers are damaged. After 1800℃ annealing, the C/SiC composites fabricated by PIP process indicate 8% mass loss rate, the mechanical properties sharply decrease over 80%, and the fracture behavior changes from toughness fracture to brittle fracture. ©, 2015, Beijing Institute of Aeronautical Materials (BIAM). All right reserved.

Ma Y.,Construction Engineering Research Institute | Chen Z.,National University of Defense Technology
Journal of Materials Engineering and Performance | Year: 2013

Away to improve the ablation properties of the C/SiC composites in an oxyacetylene torch environment was investigated by the precursor infiltration and pyrolysis route using three organic precursors (zirconium butoxide, polycarbosilane, and divinylbenzene). The ceramic matrix derived from the precursors at 1200 °C was mainly a mixture of SiC, ZrO2, and C. After annealing at 1600 °C for 1 h, ZrO2 partly transformed to ZrC because of the carbothermic reductions and completely transformed to ZrC at 1800 °C in 1 h. The mechanical properties of the composites decreased with increasing temperature, while the ablation resistance increased due to the increasing content of ZrC. Compared with C/SiC composites, the ablation resistance of the C/Zr-O-Si-C composites overwhelms because of the oxide films which formed on the ablation surfaces. And, the films were composed of two layers: the porous surface layer (the mixture of ZrO2 and SiO 2) and the dense underlayer (SiO2). © ASM International.

Song K.,Construction Engineering Research Institute | Xue Y.F.,Construction Engineering Research Institute
Applied Mechanics and Materials | Year: 2014

In this paper, the control system based on the structural characteristics of knuckle boom loader crane was designed. The control system is constituted by programmable controller, weight sensor, angle sensors, length sensor and electromagnetic unloading valves and the like. It achieves functions of torque limiting, vertical lifting and wired remote control. These functions can ensure the safe operation and improved operating efficiency. The control system has been used in large quantities of a product with favorable results. © (2014) Trans Tech Publications, Switzerland.

Zhao W.,Northwestern Polytechnical University | Liu W.L.,Northwestern Polytechnical University | Wang J.L.,Construction Engineering Research Institute
Applied Mechanics and Materials | Year: 2013

Several polymer-based drug delivery systems are being developed to enhance the extremely low water-solubility of paclitaxel (PTX). It is believed that there is a positive correlation between the compatibility of polymer-drug and the solubilization. In recent years, solubility parameters for polymer and drug were used to evaluate degree of compatibility between a drug and a polymer, which were measured using various experimental methods or estimated using the group contribution menthod (GCM). In this study, degree of compatibility between PTX and polymers were estimated by molar free energy of mixing (ΔGmix) that was calculated through computer simulation. It is found that the degree of compatibility is: PTX-PTRP > PTX-PLBG > PTX-PLGA > PTX-PCL > PTX-PLA. It has been demonstrated that the result of this study is in accord with the Similar Dissolve Mutually Theory. © (2013) Trans Tech Publications, Switzerland.

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