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Assessment of liquefaction potential based on shear wave velocity:Strain energy approach

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3733-3745页

作者： Mohammad hassan Baziar Mahdi Alibolandi School of Civil Engineering Iran University of Science and TechnologyTehran16846-13114Iran

Liquefaction assessment based on strain energy is significantly superior to conventional stress-based *** main purpose of the present study is to investigate the correlation between shear wave velocity and strain energy capacity of silty *** dissipated energy until liquefaction occurs was calculated by analyzing the results of three series of comprehensive cyclic direct simple shear and triaxial tests on Ottawa F65,Nevada,and Firoozkuh sands with varying silt content by weight and relative ***,the shear wave velocity of each series was obtained using bender element or resonant column ***,for the first time,a liquefaction triggering criterion,relating to effective overburden normalized liquefaction capacity energy(WL=s’c)to effective overburden stresscorrected shear wave velocity(eVs1)has been *** accuracy of the proposed criteria was evaluated using in situ *** results confirm the ability of shear wave velocity as a distinguishing parameter for separating liquefied and non-liquefied soils when it is calculated against liquefaction capacity energy(WL=s’c).However,the proposed WL=s’c-Vs1 curve,similar to previously proposed cyclic resistance ratio(CRR)-Vs1 relationships,should be used conservatively for fields vulnerable to liquefaction-induced lateral spreading.

关键词： Liquefaction Strain energy capacity Shear wave velocity Cyclic triaxial test Cyclic direct simple shear test Resonant column test Bender element test

Effect of Bainite Morphology on Mechanical Properties of the Mixed Bainite-martensite Microstructure in D6AC Steel

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Journal of Materials Science & Technology 2012年第4期28卷 336-342页

作者： Khodamorad Abbaszadeh hassan Saghafian Shahram Kheirandish School of Metallurgy and Materials Engineering Iran University of Science and Technology Tehran *** Iran

The effect of bainite morphology on mechanical properties of the mixed bainite-martensite microstructure in D6AC low alloy ultra-high strength steel has been studied in the present work. For this purpose, samples austenitized at 910℃ for 40 min were quenched in three different ways. Some of the samples were directly oil-quenched, some others were quenched in salt bath at 330 ℃ and the remaining samples were quenched in salt bath at 425 ℃ for various holding times. All samples were tempered at 200 ℃ for 2 h. Microstructures were examined by optical microscopy （OM） and scanning electron microscopy （SEM）. Fracture surfaces also were studied by SEM. Results showed that the mixed microstructure containing martensite and 28 vol.% of the lower bainite exhibited higher yield and tensile strengths than the fully martensitic microstructure. This could be mainly attributed to the partitioning of the prior austenite grains by the lower bainite and enhancing the strength of lower bainite in the mixed microstructure by plastic constraint. Charpy V-notch （CVN） impact energy and ductility were improved by increasing the volume fraction of the lower bainite. This is not the case about the mixed microstructure containing the upper bainite and martensite. As a result, the tensile and CVN impact properties of mixed upper bainite-martensite microstructure are lower than those of the fully martensitic microstructure. Finally, fractography studies showed cleavage fracture at the surface of CVN impact specimens with martensitic and upper bainitic microstructures confirming the tendency to brittle behavior.

关键词： Upper bainite Lower bainite Microstructure D6AC Mechanical properties

Regenerative energy management of electric drive based on Lyapunov stability theorem

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Journal of Modern Power Systems and Clean Energy 2019年第2期7卷 321-328页

作者： Shahab SABZI Mehdi ASADI hassan MOGHBELI Department of Electrical Engineering Arak University of Technology

In recent years, urban rail systems have developed drastically. In these systems, when induction electrical machine suddenly brakes, a great package of energy is produced. This package of energy can be stored in energy storage devices such as battery, ultra-capacitor and flywheel. In this paper, an electrical topology is proposed to absorb regenerative braking energy and to store it in ultracapacitor and ***-capacitor can deliver the stored energy to DC grid and charge the battery for auxiliary applications such as lighting and cooling systems The proposed system is modeled based on large signal averaged modeling, which leads to the simplicity of calculations. The control system is based on Lyapunov stability theorem which guarantees system stability. Also, an energy management algorithm is proposed to control energy under braking and steady-state conditions. Finally,the simulation results validate the effectiveness of the proposed control and energy management system.

关键词： DC/DC converter Lyapunov stability Bidirectional converter Energy management system(EMS) Ultra-capacitor Battery Switching function

Preparation,quality control and biodistribution of [^(61)Cu]-doxorubicin for PET imaging

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Nuclear Science and Techniques 2009年第3期20卷 157-162页

作者： JALILIAN Amir Reza YOUSEFNIA hassan FAGHIHI Reza AKHLAGHI Mehdi ZANDI hassan Nuclear Medicine Research Group Agricultural Medical and Industrial Research School Karaj Iran Department of Nuclear Engineering School of Engineering Shiraz University Shiraz Iran

This work was conducted for radiolabeling of an anticancer antibiotic, i.e. doxorubicin with 61Cu for production of possible tracer used in PET oncology. 61Cu was prepared with natural zinc target and 22 MeV150 μA protons via natZn(p, xn)61Cu reaction with a yield of 123.2 MBq·μA-1·h-1. Optimization reactions were performed for pH, temperature and concentration. Biodistribution of the tracer was studied in normal and fibrosarcoma bearing mice. At the optimized conditions, ITLC showed that radiochemical purity was over 97% with a specific activity of 2.22× 103MBq ·mmol-1·L-1. This was kept unchanged even with presence of human serum as well as room temperature for 5 h. Biodistribution of the tracer in fibrosarcoma bearing mice demonstrated significant tumor uptake after 2 h. This tracer can be used in the detection of various tumors responding to doxorubicin chemotherapy using PET scan and/or determination of tumor therapy response to doxorubicin chemotherapy.

关键词：放射性元素研究核技术 ^61Cu

Motion of a Nonrelativistic Quantum Particle in Non-commutative Phase Space

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Chinese Physics Letters 2015年第10期32卷 5-8页

作者： FATEME Hoseini 马凯 hassan hassanabadi physics Department University of Shahrood Shahrood ***-316 Iran School of Physics Science Shaanxi University of Technology Hanzhong 723000

The equation governing the motion of a quantum particle is considered in nonrelativistic non-commutative phase space. For this aim, we first study new Poisson brackets in non-commutative phase space and obtain the modified equations of motion. Next, using novel transformations, we solve the equation of motion and report the exact analytical solutions.

关键词： Motion of a Nonrelativistic Quantum Particle in Non-commutative Phase Space NCS

The Gain Equation of a Helical Wiggler Free Electron Laser with Ion-Channel Guiding and/or an Axial Magnetic Field

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Chinese Physics Letters 2013年第3期30卷 56-59页

作者： Taghi Mohsenpour hassan Ehsani Amri Department of Physics Faculty of Basic SciencesMazandaran UniversityBabolsarIran Department of Physics Islamic Azad UniversityNour BranchIran

Electron motion in the combined ion-channel,helical wiggler and axial magnetic fields is analyzed in the absence of a radiation *** analysis of the gain equation in a free-electron laser is *** calculations are made to illustrate the effects of the two electron-beam guiding devices on the gain when applied separately and simultaneously.

关键词： Electron Wiggler Channel

Theoretical description of electron-phonon Fock space for gapless and gapped nanowires

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Chinese Physics B 2017年第3期26卷 404-409页

作者： Ashrafalsadat Shariati hassan Rabani Mohammad Mardaani Department of Physics Faculty of Science Shahrekord University P. O. Box 115 Shahrekord Iran Nanotechnology Research Center Shahrekord University *** Shahrekord Iran

We study the effect of electron-phonon （e-ph） interaction on the elastic and inelastic electronic transport of a nanowire connected to two simple rigid leads within the tight-binding and harmonic approximations. The model is constructed using Green＇s function and multi-channel techniques, taking into account the local and nonlocal e-ph interactions. Then, we examine the model for the gapless （simple chain） and gapped （PA-like nanowire） systems. The results show that the tunneling conductance is improved by the e-ph interaction in both local and nonlocal regimes, while for the resonance conductance, the coherent part mainly decreases and the incoherent part increases. At the corresponding energies which depend on the phonon frequency, two dips in the elastic and two peaks in the inelastic conductance spectra appear. The reason is the absorption of the phonon by the electron in transition into inelastic channels.

关键词： Theoretical description of electron phonon Fock space for gapless and gapped nanowires

DISTRIBUTED WATER BALANCE WITH RIVER DYNAMIC-DIFFUSIVE FLOW ROUTING MODEL

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Journal of Hydrodynamics 2009年第4期21卷 564-572页

作者： hassan Ahmed NORIO Tanaka NOBUYUKI Tamai Graduate School of Science and Engineering Saitama University Graduate School Kanazawa Gakuin University

This article focuses on the application of coupling both river dynamic and river diffusive modeling techniques that can be used with distributed water balance model. In an upstream watershed, both overland and river diffusive flows are routed by diffusive wave approximation of the free surface flow equations. In river downstream reaches, the river dynamic flow is routed by one-dimensional dynamic wave equations （full dynamic St. Venant equations with lateral flow）. The developed model is applied in a part of Arakawa River basin, Kanto area, Japan. The geographic data of river cross sections could be accurately represented by an 11-point cross-section approximation. The effects of both the grid size and lateral flow on the simulated results of the river dynamic flow model were studied. The grid size should be greater than the average width of the river cross-sections. The lateral flow from small drainage systems has significant effects on the simulated results using the river dynamic flow model. The simulated results show good and acceptable agreements with the observed flow discharges and water depths. Both the river discharge and water depth at any location of river network of compound channels with one/two complex floodplains could be correctly estimated.

关键词： diffusive model dynamic model natural compound channels floodplains

A method for matching response spectra of endurance time excitations via the Fourier transform

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 637-648页

作者： Mohammadreza Mashayekhi Homayoon EEstekanchi hassan Vafai Department of Civil Engineering Sharif University of TechnologyTehranIran

The endurance time(ET)method is a dynamic analysis in which structures are subjected to intensifying excitations,also known as ET excitation functions(ETEF).The ET method is a tool for structural response *** main advantage of the ET method over conventional approaches is its much lower demand for computational *** concept of acceleration spectra is used in generating existing *** is expected that ETEF acceleration spectra increase consistently with time and remain proportional to a target *** unconstrained optimization is commonly used to generate *** new ETEFs is a complicated time-consuming mathematical *** the target acceleration spectrum changes,new ETEFs must be *** study intends to modify existing ETEFs to be compatible with a desired acceleration *** process,called spectral matching,obviates the need for using the complicated generating procedure in simulating new *** spectral matching is introduced in this paper for the first time.A Fourier-based method for ETEFs spectral matching is *** algorithm is then applied in a case *** are presented to prove the efficiency of the algorithm.

关键词： spectrum. excitation acceleration