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Mechanical properties of frozen rock mass with two diagonal intersected fractures

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International Journal of Mining Science and Technology 2018年第4期28卷 626-633页

作者： Hao Yang Renliang Shan Jinxun Zhang Fumei Wu Zhiming Guo School of Mechanics and Civil Engineering China University of Mining & Technology postdoctoral workstation Beijing Urban Construction Group CO. Ltd.

Based on previous research results, this paper investigated the influence of fracture morphology on mechanical properties and failure modes of rock mass with two diagonal intersected fractures. This study carried out a series of triaxial compression tests on rock-like specimens with two crossed fractures under negative temperature, concluded the following conclusions. The strength and failure modes of rock mass are significantly influenced by the dips of two crossed fractures. The strength of rock mass with two frac- tures cannot simply be estimated using the method that was developed for the rock mass with a single fracture. When the intersecting angle is less than 30~, the failure plane initiates at the tip of ＂artificial rup- tures＂ and extends to the upper and lower ends of the specimen. In case of a higher dip and intersecting angle ranging from 30° to 60°, the failure plane propagates along one of these two fractures. The mechan- lca! parameters of rock mass are not only related to the trace length, but also depend on the trace !ength ratio. One could roughly calculate the strength parameters using the approximation proposed *** paper..For the rock mass with a trace length ratio 〈0.3 （short trace length/long trace length）, the failure mode is dependent on the fracture with a longer trace length. When the trace length becomes significant and the trace length ratio approximates to 1, the failure plane propagates along two fractures, where an *** pattern is presented： For the rock mass with moderate frac!ures and a trace length ratio of approxlmately 1, the failure mode *** on fractures, which is simllar to .the damage pattern of intact rock. The strength, and elastic .modulus of rock mass decrease with the increase of spacing between fractures, whl!e Polsson＇s ratio is Independent on the spacing. The failure mode can be deter- mined by the area. of triangle created by two fractures. Damage occurs at the smaller triangle area first, an

关键词： Intersected fractures Fracture morphology Failure modes Mechanical properties

Finite Element Analysis of the Steel Reinforced Plastic Pipe

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Journal of Materials Science & Technology 2003年第Z1期19卷 43-45页

作者： Hongyi SUN Wenqi MA Dachang KANG Keding ZHAO Harbin University of Science and Technology Harbin 150080 China Daqing Oilfields postdoctoral workstation Daqing 163453 China Harbin Institute of Technology Harbin 150001 China Daqing Oilfields postdoctoral workstation Daqing 163453 China Harbin Institute of Technology Harbin 150001 China Harbin Institute of Technology Harbin 150001 China

The steel reinforced plastic pipe is a kind of green environmental protection pipelines with double-sides corrosionresisting and better withstanding to medium working pressure. The structure and technical process of this pipe are described briefly in this paper, and the finite element analysis has been done for the sake of understanding the distributions of stress and displacement inside this pipe under hydrostatic pressure. The analysis results are very important for safety application of the steel reinforced plastic pipe.

关键词： Steel reinforced plastic pipe, Finite element analysis

Discrete element method study of parameter optimization and particle mixing behaviour in a soil mixer

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Particuology 2023年第10期81卷 1-14页

作者： Ming Bao Jiming Lin Feng Zhang Jianhong Yang College of Mechanical Engineering and Automation Huaqiao UniversityXiamen361021China postdoctoral workstation Fujian South Highway Machinery CompanyQuanzhou362021China

Soil mixing is an emerging research in the field of construction resource *** this study,the mixing behaviour of soil particles in a mixer is numerically simulated by the discrete element method(DEM).A four-factor,three-level orthogonal experiment is designed to optimize the mixer design by selecting the fly-cutter speed,spindle speed,number of blades and fly-cutter diameter,using Lacey mixing index and power consumption as evaluation ***,the impact of soil cohesion and type on the mixing behaviour is *** results show that the optimal parameter combination of this experiment is 280 rpm fly-cutter speed,40 rpm spindle speed,4 blades and 250 mm fly-cutter *** optimal combination reaches a comparatively uniform state mix in 5.9 s with an average power consumption of 704.11 *** addition,the wear and tear of the mixer increases as soil cohesion increases,while the mixing quality of materials declines,resulting in a“shaft hugging”*** mixing efficiency varies greatly among different soil types,but the radial and tangential velocities have a similar *** work can provide some guidance for the optimization design of a mixer and study of soil mixing.

关键词： Soil mixing Discrete element method Orthogonal experiment Laceymixing index Soil cohesion

Evaluation of anti-fouling performance for ion-rod water treater with automatic dynamic simulator of fouling

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化工学报 2005年第4期56卷 668-671页

作者：孙灵芳杨善让秦裕琨徐志明 Power Engineering and Engineering Thermophysics postdoctoral workstation Harbin Institute of Technology Harbin 150001HeilongjiangChina Energy Conservation and Measurement-control Technique Research Center Northeast China Institute of Electric Power EngineeringJilin 132044JilinChina Power Engineering and Engineering Thermophysics postdoctoral workstation Harbin Institute of Technology Harbin 150001HeilongjiangChina

The application of a novel Automatic Dynamic Simulator of Fouling (ADSF) to evaluate the effectiveness of ion-rod water treater is *** effects of some parameters of the water treater were studied with an ADSF made according to patented technology, and orthogonal experimental design was adopted with the use of artificial hard *** results validated that the ion-rod water treater could mitigate fouling,and the anti-fouling efficiency varies with the test *** anti-fouling efficiency of treater increased with the increase of flow velocity in the range of 0.8—1.2 m·s -1 and output voltage in the range of 7500—15000 *** efficiency weat up initially, and then went down with the increase in *** rough surface of ion-rod was superior to the smooth *** order of influence on treater performance with respect to these factors was as follows: water hardness, roughness of surface, flow velocity and output *** research also provided a guide to improving the performance of ion-rod water treater.

关键词：污垢离子棒水处理器阻垢性能

Preliminary Application of Scale Transformation Stochastic Resonance in Dual-Sequence Frequency Hopping System

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Journal of Shanghai Jiaotong university(Science) 2019年第6期24卷 775-781页

作者： LIU Guangkai SUN Huixian QUAN Houde CUI Peizhang ZHU Shilei CHI Kuo Army Engineering University Shijiazhuang050003China 66393 Troops postdoctoral Science Research workstation Baoding 071002HebeiChina

Aiming at the detection failure of strong noise interference in the dual channel of the dual-sequence frequency hopping(DSFH),the scale transformation stochastic resonance(STSR)is applied for the first time,and the output signal to noise ratio(SNR)is raised effectively,at the same time,the symbol reception is completed for DSFH at low input ***,the radio frequency(RF)and intermediate frequency(IF)signals are analyzed based on the super-heterodyne reception of DSFH;secondly,the equations of probability density function(PDF),output power spectrum and SNR of the STSR output are derived for the IF signal;finally,the algorithm of the optimal matching STSR is proposed with the optimal matching *** simulation results show that the algorithm can effectively solve the detection failure,as the global output SNR of DSFH is strongly improved that the output SNR can reach-17.72 d B when the input SNR is-20 d B after the processing of the optimal matching STSR.

关键词： the dual-sequence frequency hopping(DSFH) detection of weak signal scale transformation stochastic resonance(STSR) the optimal matching stochastic resonance

EXTRUSION DIE CAE OF THE STEEL REINFORCED PLASTIC PIPE

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 303-306页

作者： W.Q.Ma H.Y.Sun D.C.Kang K.D.Zhao Harbin Institute of Technology Harbin 150001 China Daqing Oilfield Postdoctoral Workstation Daqing 163453 ChinaHarbin University of Science and Technology Harbin 150080 China Daqing Oilfield Postdoctoral Workstation Daqing 163453 ChinaHarbin Institute of Technology Harbin 150001 ChinaHarbin Institute of Technology Harbin 150001 China

The steel reinforced plastic pipe is a new kind of pressure pipe. It is made up with steelwires and plastic. Because reinforced skeleton of the steel wire increase the complexityof plastic flow during the extrusion phase, the traditional design criteria of extrusiondie is not suitable. The study on extrusion die of the kind of pipe is very importantstep in produce development. Using finite element (FE) method in this paper, theflow rule of molten plastic inside the die has been predicted and a groap of optimalstructural parameters was obtained. These results are helpful for reducing the designcycle and improve the quality of the final product.

关键词： steel reinforced plastic pipe extrusion die computer aid engineering(CAE)

FBG-based ultrasonic wave detection and acoustic emission linear location system

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Optoelectronics Letters 2012年第3期8卷 220-223页

作者：姜明顺隋青美贾磊彭蓬曹玉强 School of Control Science and Engineering Shandong University Yanzhou Coal Mining Group Co.Ltd. Postdoctoral Workstation

The ultrasonic (US) wave detection and an acoustic emission (AE) linear location system are proposed, which employ fiber Bragg gratings (FBGs) as US wave sensors. In the theoretical analysis, the FBG sensor response to longitudinal US wave is investigated. The result indicates that the FBG wavelength can be modulated as static case when the grating length is much shorter than US wavelength. The experimental results of standard sinusoidal and spindle wave test agree well with the generated signal. Further research using two FBGs for realizing linear location is also achieved. The maximum linear location error is obtained as less than 5 mm. FBG-based US wave sensor and AE linear location provide useful tools for specific requirements.

关键词： Acoustic emissions Sensors Signal detection

Direct decomposition of nitric oxide in low temperature over iron-based perovskite-type catalyst modified by Ru

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Journal of Harbin Institute of Technology(New Series) 2006年第5期13卷 568-570页

作者：李丽张密林袁福龙史克英张国张丹 postdoctoral workstation of Materials Science and Technology Harbin Engineering University Harbin 150001ChinaSchool of Chemistry and Materials Science Heilongjiang University Harbin 150080 China postdoctoral workstation of Materials Science and Technology Harbin Engineering University Harbin 150001China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Iron-based perovskite-type compounds modified by Ru were prepared through sol-gel process to study its catalytic activity of NOx direct decomposition at low temperature and evaluate the conversion of NO under the experimental conditions. The catalytic activity of La 0.9Ce 0.1Fe 0.8-nCo 0.2RunO3 （n=0.01,0.03,0.05,0.07,0.09）series for the NO, NO-CO two components, CO-HC-NO three components were also analyzed. The catalytic investigation evidenced that the presence of Ru is necessary for making highly activity in decomposition of nitric oxide even at low temperature（400 ℃）and La 0.9Ce 0.9Fe 0.75Co 0.2Ru 0.05O3 （n=0.05） has better activity in all the samples, the conversion of it is 58.5%. With the reducing gas（CO,C3H6）added into the gas, the catalyst displayed very high activity in decomposition of NO and the conversion of it is 80% and 92.5% separately.

关键词： iron-based perovskite-type compounds catalyst modified by Ru direct decomposition of nitric oxide in low temperature catalytic activity

Mechanical Properties of Two Kinds of New Cold-Formed Flange-Closed Welding Section Members

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沈阳建筑大学学报（自然科学版） 2011年第6期27卷 1021-1032页

作者：武胜 College of Civil Engineering Northeast Forestry University workstation for postdoctoral Fellows of Heilongjiang Construction Engineering Group Research Station on Civil Engineering for postdoctoral Fellows of Harbin Institute of Technology

The hollow flange beam(HFB) is a unique cold-formed steel section developed in Australia for use as a flexural ***′s a particular cross section with two torsion rigid closed triangular flanges and a comparatively flexible web,and it is a type of high efficient cross *** paper presents two kinds of new cold-formed flange-closed welding sections named HF1 and HF2 according to different section component and parameters of *** finite element method has been adopted to investigate the mechanical properties such as buckling mode,deformation process,rigidity,ductility and correlation curve of two kinds of new section members which being subjected to axial compression,flexure,combined compression and *** comparisons of the consumed steel quantities of per unit load carrying capacity between new section members and the same section dimensions of cold-formed C-section members have been carried *** conclusions can be drawn from above work that the new sections have some superior properties including higher load carrying capacity and section modulus,sufficient section stiffness,and difficult occurrence for the sub element local *** new sections are suitable for bearing flexure,compression,combined compression and *** new sections′ consumed steel quantities of per unit load carrying capacity are almost half as those of the same dimension C-section members′.The experimental investigation is carried out further on the new cold-formed flange-closed welding section members and can be used in the practical engineering.

关键词： hollow flange beam cold-formed steel members finite element analysis mechanical properties