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Microbiostratigraphy, microfacies and sequence stratigraphy of upper cretaceous and paleogene sediments, Hendijan oilfield, Northwest of Persian Gulf, Iran

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Natural Science 2013年第11期5卷 1165-1182页

作者： bahman Soleimani Alireza bahadori Fanwei Meng Department of Geology Faculty of Earth Sciences Shahid Chamran University Ahvaz Iran State Key Laboratory of Paleobiology and Stratigraphy Nanjing Institute of Geology and Paleontology Chinese Academy of Sci- ences Nanjing China

Hendijan oilfield is located on Northwest of Pesian Gulf offshore of Iran and geologically in the Dezful embayment. In this study, the paleosedimentary depositional environment of the Early Cenomanian to Late Eocene deposits of the Sarvak, Ilam, Gurpi, Pabdeh and JahrumPabdeh Formations was evaluated using microbiostratigraphy, microfacies and D-INPEFA curves which are an accurate method in sequence stratigraphy in terms of regression and transgression of the sea. Also, we used limited elemental geochemical data of oxygen and carbon isotopes in compare with palaeontological data to infer the upper part, 10 m, of the Sarvak Formation. Statistical correlation analyses of geochemical data from upper part of the Sarvak Formation enable inference of differences in paleoconditions at this part and Sarvak Formation, and another Formation, Ilam, was distinguished. Palaentilogical analysis using planktonic foraminifera and calcareous nannofossils enables inference about time scale of each Formation. Petrographic data and different sediment textures support those inferences resulted from Gamma ray logs as D-INPEFA curves about different paleo-conditions that occurred during the development of the studied Formations. Synthesis of the analyses leads to the final interpretation that upper Cretaceous, Sarvak, Ilam and Gurpi Formations, at the Hendijan oil field were formed in a carbonate ramp that was likely closed to the open sea, where Gurpi Formation was deposited, by a shallow barrier that allowed seawater recharge into the basin and deep marine basin where Paleogene sediments, Pabdeh and Jahrum-Pabdeh, were deposited.

关键词： Upper Cretaceous Paleogene Planktonic Foraminifera Microfacies Sequence Stratigraphy Hendijan Oil Field (SW Iran)

Progress in Thermomechanical Analysis of Friction Stir Welding

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 11-43页

作者： bahman Meyghani Chuansong Wu Institute of Materials Joining Shandong UniversityJinan 250061China

This article reviews the status of thermomechanical analysis of the friction stir welding(FSW)process for establishing guidelines for further investigation,filling the available research gaps,and expanding FSW ***,the advantages and applications of FSW process are introduced,and the significance and key issues for thermomechanical analysis in FSW are pointed ***,solid mechanic and fluid dynamic methods in modeling FSW process are described,and the key issues in modeling FSW are *** erent available mesh modeling techniques including the applications,benefits and shortcomings are *** that,at different subsections,the thermomechanical analysis in FSW of aluminum alloys and steels are examined and summarized in ***,the conclusions and summary are presented in order to investigate the lack of knowledge and the possibilities for future study of each method and each material.

关键词： Thermomechanical analysis Friction stir welding Solid mechanic Fluid dynamic Mesh modeling techniques Aluminum alloys and Steels

Thermal treatment effect on structural features of mechano-synthesized fluorapatite-titania nanocomposite: A comparative study

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Journal of Advanced Ceramics 2014年第1期3卷 31-42页

作者： bahman NASIRI-TABRIZI Materials Engineering Department Najafabad BranchIslamic Azad UniversityNajafabadIsfahanIran

The influence of thermal treatment on the structural features of mechano-synthesized fluorapatite-titania composite nanopowders was studied.A mixture of calcium and phosphate reagents was mixed with a certain amount of titania(20 wt%)and then was mechanically activated for 5 h,10 h and 15 h *** that,the mechano-synthesized powders were annealed at 700℃for 2 *** crystallite size of the composite nanopowders estimated from Williamson-Hall method was in good agreement with transmission electron microscopy(TEM)*** electron microscopy(SEM)/TEM images confirmed the formation of a cluster-like composite which was composed of ellipse-like nanoparticles with an average size of about 16±7 nm after 15 h of *** the milling process,large variations in mechanochemical behavior of the CaHPO_(4)-Ca(OH)_(2)-CaF2-TiO_(2) system were *** the beginning of milling,no trace of the composite was found due to the lack of sufficient time for the mechanical *** the mechanical activation time increased to 15 h,composite nanopowders with the crystallite size of around 21.66 nm were *** heating at 700℃,the recovery of crystallinity occurred and the fraction of crystalline phase reached a maximum around 88.79%for the 10-h milled *** indicated that the structural features of the composite were strongly influenced by the subsequent annealing.

关键词： nanocomposite fluorapatite thermal treatment Williamson-Hall method structural features

Assessing dynamic response of multispan viscoelastic thin beams under a moving mass via generalized moving least square method

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Acta Mechanica Sinica 2010年第5期26卷 721-733页

作者： Keivan Kiani Ali Nikkhoo bahman Mehri Department of Civil Engineering Sharif University of Technology Department of Mathematical Sciences Sharif University of Technology

Dynamic response of multispan viscoelastic thin beams subjected to a moving mass is studied by an efficient numerical method in some detail. To this end, the unknown parameters of the problem are discretized in spatial domain using generalized moving least square method （GMLSM） and then, discrete equations of motion based on Lagrange＇s equation are obtained. Maximum deflection and bending moments are considered as the important design parameters. The design parameter spectra in terms of mass weight and velocity of the moving mass are presented for multispan viscoelastic beams as well as various values of relaxation rate and beam span number. A reasonable good agreement is achieved between the results of the proposed solution and those obtained by other researchers. The results indicate that, although the load inertia effects in beams with higher span number would be intensified for higher levels of moving mass velocity, the maximum values of design parameters would increase either. Moreover, the possibility of mass separation is shown to be more critical as the span number of the beam increases. This fact also violates the linear relation between the mass weight of the moving load and the associated design parameters, especially for high moving mass velocities. However, as the relaxation rate of the beam material increases, the load inertia effects as well as the possibility of moving mass separation reduces.

关键词： Moving mass-beam interaction - Multispan viscoelastic beam Euler-Bernoulli beam Generalized moving least square method (GMLSM)

Laser conditioning and structuring of grinding tools--a review

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Advances in Manufacturing 2017年第1期5卷 35-49页

作者： bahman Azarhoushang Ali Zahedi Institute of Precision Machining (KSF) FurtwangenUniversity of Applied Sciences Jakob-Kienzle-Strasse 1778054 Villingen-Schwenningen Germany

The conditioning of grinding tools is one of the most important factors for achieving an optimal grinding process. It influences the grinding forces and temperatures and, therefore, the achievable material removal rate, dimensional accuracy and the surface integrity of the workpiece. Furthermore, the roundness, profile accuracy and the wear of the grinding tools are strongly influenced by the conditioning process. The conditioning process should be matched to the abrasive type and the bonding of the grinding tool. Laser conditioning is a promising unconventional and non-contact method, which is able to condition all kinds of abrasives and bonding types. The main advantages of this novel method are no tool wear, good repeatability and controllability, high precision and a relatively short process time. Additionally, using this method, grinding tools can be micro-structured. This paper reviews the literature on the laser conditioning of grinding tools, covering the associated setups, wheel conditioning and structuring mechanisms, and experimental results. It also discusses the technical barriers that have to be overcome before laser conditioning can be fully integrated into manufacturing.

关键词： Laser conditioning Structuring Dressing -Truing Grinding tool. Grinding

Real-time assessment of tunnelling-induced damage to structures within the building information modelling framework

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Underground Space 2024年第1期14卷 99-117页

作者： Jelena Ninic Ali Gamra bahman Ghiassi School of Engineering University of BirminghamB152TTUK Centre for Structural Engineering and Informatics The University of NottinghamNG72RDUK

During the initial design phases of complex multi-disciplinary systems such as urban tunnelling,the appraisal of different design alternatives can ensure optimal designs in terms of costs,construction time,and *** enable the evaluation of a large number of design scenarios and to find an optimal solution that minimises impact of tunnelling on existing structures,the design and assessment process must be efficient,yet provide a holistic view of soil-structure interaction *** paper proposes an integrated tunnel design tool for the initial design phases to predict the ground settlements induced by tunnelling and building damage using empirical and analytical solutions as well as simulation-based meta ***,visualisation of ground settlements and building damage risk is enabled by integrating empirical and analytical models within our Building Information Modelling(BIM)framework for *** approach allows for near real-time assessment of structural damage induced by settlements with consideration of soil-structure interaction and non-linear material ***,because this approach is implemented on a BIM platform for tunnelling,first,the design can be optimised directly in the design environment,thus eliminating errors in data exchange between designers and computational ***,the effect of tunnelling on existing structures can be effectively visualised within the BIM by producing risk-maps and visualising the scaled deformation field,which allows for a more intuitive understanding of design actions and for collaborative *** a fully parametric design model and real-time predictions therefore enables the assessment and visualisation of tunneling-induced damage for large tunnel sections and multiple structures in an effective and computationally efficient way.

关键词： Building information modelling Soil-structure interaction Tunnelling Settlements Structural damage Visualisation Meta models

Fabrication of a highly efficient new nanocomposite polymer gel for controlling the excess water production in petroleum reservoirs and increasing the performance of enhanced oil recovery processes

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Chinese Journal of Chemical Engineering 2021年第4期34卷 385-392页

作者： Sajad Asadizadeh Shahab Ayatollahi bahman ZareNezhad Faculty of Chemical Petroleum and Gas EngineeringSemnan UniversitySemnanIran Chemical and Petroleum Engineering Department Sharif University of TechnologyTehranIran

A new nanocomposite polymer gel is synthesized for reduction of excess water production in petroleum reservoirs at real operating *** new nanocomposite gel contains SiO2 nanoparticles,partially hydrolyzed polyacrylamide(HPAM)and chromium *** pressure and high temperature tests using porous carbonate core are carried out to evaluate the effects of nanoparticles on the synthesized polymer gel *** is shown that the residual resistance factor ratio of water to oil using the synthesized polymer gel nanocomposite in this work is much higher than that of the ordinary polymer *** presented results confirm the high performance of the synthesized nanocomposite polymer gel for decreasing the water flow through porous carbonate bed.A mathematical model for description of oil and water flow behavior in the presence of synthesized nanocomposite polymer gel is also *** presented nano polymer gel leads to considerable cost saving in enhanced oil recovery(EOR)processes.

关键词： Petroleum Excess water Nanocomposite Polymer gel Nanoparticle EOR

Optimal operation of energy at hydrothermal power plants by simultaneous minimization of pollution and costs using improved ABC algorithm

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Frontiers in Energy 2015年第4期9卷 426-432页

作者： Homayoun EBRAHIMIAN bahman TAHERI Nasser YOUSEFI Department of Engineering Ardabil Branch Islamic Azad University Ardabil 0451 Iran Young Researchers and Elite Club Ardabil Branch Islamic Azad University Ardabil 0451 Iran

The aim of this paper is simultaneous mini- mization of hydrothermal units to reach the best solution by employing an improved artificial bee colony （ABC） algorithm in a multi-objective function consisting of economic dispatch （ED） considering the valve-point effect and pollution function in power systems in view of the hot water of the hydro system. In this type of optimization problem, all practical constraints of units were taken into account as much as possible in order to comply with the reality. These constraints include the maximum and minimum output power of units, the constraints caused by the balance between supply and demand, the impact of pollution, water balance, uneven production curve con- sidering the valve-point effect and system losses. The proposed algorithm is applied on the studied system, and the obtained results indifferent operating conditions are analyzed. To investigate in various operating conditions, different load profiles in 12 h are taken into account. The obtained results are compared with those of the other methods including the genetfc algorithm （GA）, the Basu technique, and the improved genetic algorithm. Fast convergence is one of this improved algorithm features.

关键词： practical constraints of units pollution func-tion inlet steam valve up-ramp rate of units improvedABC algorithm

Characterization of mechanothermal-synthesized hydroxyapatite-magnesium titanate composite nanopowders

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Journal of Advanced Ceramics 2013年第1期2卷 63-70页

作者： Abbas FAHAMI bahman NASIRI-TABRIZI Materials Engineering Department Najafabad BranchIslamic Azad UniversityNajafabadIsfahanIran

Hydroxyapatite-magnesium titanate composite nanopowders have been developed using a mechanothermal *** treatment of the milled powders at 700℃resulted in the formation of HAp/MgTiO_(3)-MgO nanocomposite.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and energy dispersive X-ray spectroscopy(EDX)techniques were utilized to characterize the synthesized *** results revealed that the dominant phases after mechanical activation were hydroxyapatite,anatase(TiO_(2))and periclase(MgO);while after thermal annealing process at 700℃,hydroxyapatite along with geikielite(MgTiO_(3))and periclase(MgO)were the major *** on the XRD analysis,the evaluation of structural features of the samples indicated that the average crystallite sizes of hydroxyapatite after 10 h of milling and subsequent thermal treatment at 700℃were about 21 nm and 34 nm,*** observations illustrated that the synthesized powders contained large agglomerates which consisted of significantly finer particles with spheroidal *** is concluded that the mechanothermal method can be used to produce hydroxyapatite-based nanocomposite with appropriate structural and morphological features.

关键词： HAp/MgTiO_(3)-MgO nanocomposite characterization methods mechanothermal