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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

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

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)

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

Entire Catchment and Buffer Zone Approaches to Modeling Linkage Between River Water Quality and Land Cover——A Case Study of Yamaguchi Prefecture,Japan

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Chinese Geographical Science 2008年第1期18卷 85-92页

作者： bahman Jabbarian AMIRI Kaneyuki NAKANE Division of Environmental Dynamics and Management Graduate School of Biosphere Science Hiroshima University 1-7-1 Kagamiyama Higashi-Hiroshima 739-8521 Japan

This study investigated the linkages between river water quality and land use in river catchments in Yama- guchi Prefecture, the western Japan, in order to examine the effect of land use changes of both entire catchment and buffer zone on river water quality. Dissolved Oxygen (DO), pH, Biological Oxygen Demand (BOD), Suspended Solids (SS), Escherichia coli, Total Nitrogen (TN) and Total Phosphorus (TP) were considered as river water quality indica- tors. Satellite images were applied to generating the land use map. Multiple regression model was applied to linking the changes in the river water quality with the land uses in both entire catchment area and buffer zone. The results in- dicate that the integrative application of land use data from the entire catchment and the buffer zone could give rise to more robust model to predict the concentrations of Suspended Solids (r2=0.88) and Total Nitrogen (r2=0.90), rather than models which separately considered land use data in catchment and buffer zone.

关键词： land use water quality buffer zone entire catchment Yamaguchi Prefecture Japan

Three-dimensional simulation of long-wavelength free-electron lasers with helical wiggler and ion-channel guiding

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Chinese Physics B 2013年第7期22卷 183-191页

作者： F. Jafari bahman B. Maraghechi Department of Physics Amirkabir University of Technology

A three-dimensional simulation of a steady-state amplifier model of a long-wavelength free-electron laser （FEL） with realizable helical wiggler and ion-channel guiding is presented. The set of coupled nonlinear differential equations for electron orbits and fields of TE 11 mode in a cylindrical waveguide are solved numerically by the Runge–Kutta algorithm with averages calculated by the Gaussian quadrature technique. Self-fields and space-charge effects are neglected, and the electron beam is assumed to be cold and slippage is ignored. The parameters correspond to the Compton regime. Evolution of the radiation power and growth rate along the wiggler is studied. Ion-channel density is chosen to obtain optimum efficiency. Simulations are preformed for the FEL operating in the neighborhood of 35 GHz and 16.5 GHz for the electron beam energies of 250 keV and 400 keV, respectively. The result of the saturated efficiency was found to be in good agreement with the simple estimation based on the phase-trapping model.

关键词： free-electron laser helical wiggler ion-channel guiding

Rice(Oryza sativa L.)plant protection using dual biological control and plant growth-promoting agents:Current scenarios and future prospects

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Pedosphere 2023年第2期33卷 268-286页

作者： Debasis MITRA Sergio DE LOS SANTOS-VILLALOBOS Fannie Isela PARRA-COTA Ana María Garcia MONTELONGO Erika Lorena BLANCO Vanessa L.LIRA Adeyemi N.OLATUNBOSUN bahman.khoshru Rittick MONDAL Parameswaran CHIDAMBARANATHAN Periyasamy PANNEERSELVAM Pradeep K.DAS MOHAPATRA Department of Microbiology Raiganj UniversityRaiganjUttar DinajpurWest Bengal 733134(India) Instituto Tecnológico de Sonora 5 de febrero 818.Col.CentroCd.ObregónSonora 85000(Mexico) Campo Experimental Norman E.Borlaug-Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias(INIFAP)Norman E.Borlaug Km.12C.P.Ciudad ObregónSonora 85000(Mexico) Laboratorio de Investigación en Biotecnología y Química de Polímeros Decanato de InvestigaciónUniversidad Nacional Experimental del TáchiraSan Cristóbal 5001(Venezuela) Departamento de Micologia Federal University of PernambucoRecifePE 50670-901(Brazil) Department of Plant Physiology and Crop Production Federal University of AgricultureAbeokuta 111101(Nigeria) Department of Soil Science Faculty of AgricultureUniversity of TabrizTabriz 51664(Iran) Department of Sericulture Raiganj UniversityRaiganjUttar DinajpurWest Bengal 733134(India) Biotechnology Crop Improvement DivisionIndian Council of Agricultural Research(ICAR)-National Rice Research InstituteCuttackOdisha 753006(India) Microbiology Crop Production DivisionICAR-National Rice Research InstituteCuttackOdisha 753006(India) Professor A.K.Bothra Environment Conservation Centre Raiganj UniversityRaiganjUttar DinajpurWest Bengal 733134(India)

Various microorganisms live in association with different parts of plants and can be harmful,neutral,or beneficial to plant *** microbial inhabitants of plants can control plant diseases by contesting with,predating on,or antagonizing plant pathogens and by inducing systems for plant defense.A range of methods,including plant growth-promoting microorganisms(PGPMs)as biological control agents(BCAs)(BCA-PGPMs)are used for the biological management and control of plant *** BCAs interact with plants by inducing resistance or priming plants without direct interaction with the *** BCAs operate via nutrient competition or other mechanisms to modulate the growth conditions for the ***,PGPMs can be applied alone or together with other chemicals or carriers to control various crop *** review highlights the effective types of BCA-PGPMs and their applications,roles,carrier based-formulations,and responses to rice(Oryza sativa L.)*** plant disease management prospects are promising,and growers’increasing demand for BCA-PGPM products can be exploited as an effective approach to the management of plant diseases,as well as to improve yield,environmental protection,biological resources,and agricultural system sustainability.

关键词： biological control agent plant disease plant growth-promoting microorganism plant health plant pathogen

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