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Chinese Journal of Polymer Science 2005年第5期23卷 539-548页

作者： S.S.Madaeni a.rahimpour Department Of Chemical Engineering Razi University KermanshahIran

Polyethersulfone membranes were prepared from quaternary systems containing N,N-dimethylacetamide （DMAc） as solvent, polyvinylpyrrolidone （PVP） as constant additive and acetic acid, acetone and water as variable additives. Phase inversion via immersion precipitation was employed for manufacturing of membranes. The prepared films were immersed in the mixture of pure water and 2-propanol （30/70 vol%） as the non-solvent. Acetic acid caused an increment in the flux at high polymer concentration （16 wt%） and a decline in the flux at low polymer concentrations （10 wt% and 13 wt%）. Acetone and water as the solvent in the casting solution declined the flux at any polymer concentration tested. The morphology and performance of the prepared membranes were investigated by scanning electron microscopy and separation experiments using milk as the feed.

关键词： Membrane Ultrafiltartion Polyethersulfone Phase inversion Milk.

RETRACTED: Determination of the Mesalazine Solubility at Biorelevant Temperature

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International Journal of Analytical Mass Spectrometry and Chromatography 2024年第1期12卷 1-12页

作者： Ekin Güler Kader Poturcu Elaheh rahimpour Abolghasem Jouyban Faculty of Engineering and Natural Sciences Department of Chemistry Suleyman Demirel University Isparta Trkiye Pharmaceutical Analysis Research Center and Faculty of Pharmacy Tabriz University of Medical Sciences Tabriz Iran

Short Retraction NoticeThis article has been retracted to straighten the academic record. In making this decision the Editorial Board follows COPE's Retraction Guidelines. The aim is to promote the circulation of scientific research by offering an ideal research publication platform with due consideration of internationally accepted standards on publication ethics. The Editorial Board would like to extend its sincere apologies for any inconvenience this retraction may have caused. The full retraction notice in PDF is preceding the original paper, which is marked "RETRACTED".

关键词： Mesalazine Solubility Shake-Flask Method Biorelevant Temperature XRD

Coal petrology,sedimentology and depositional environment of the Parvadeh coais in the Upper Triassic,Tabas Block of Central-East Iran

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International Journal of Coal Science & Technology 2023年第3期10卷 58-77页

作者： Ziba Zamani Hossain rahimpour-Bonab Ralf Littke School of Geology College of ScienceUniversity of TehranTehranIran Energy and Mineral Resources(EMR) RWTH Aachen UniversityAachenGermany

Peat forming environment strongly influences the economic value of any coal seam and coal-bearing ***,pal-aeoenvironmental studies provide important information for coal resource *** this context,detailed studies on selected coals from the Parvadeh Area,Iran,were conducted using sedimentology,coal petrology,X-ray diffraction(XRD),scanning electron microscopy-energy dispersive X-ray analyzer(SEM-EDX),and proximate *** sedi-mentary facies above and below the coal seams are mainly marine or marine-influenced facies,supporting that the coal-forming mires in the Parvadeh Area developed in a paralic environment,where the base level must be closely related to sea *** contents are moderate to high and mark the influence of brackish/marine water,especially during transgres-sion after peat growth in a lower delta plain *** peat-forming mires extended on coastal/delta plain *** lower delta plain/coastal plain coals are characterized by lateral continuity and substantial thickness,whereas few coals possibly representing the upper delta plain are thin and more *** detrital nature and composition of the numerous partings and the overall high ash yield in the coal seams indicate an active tectonic area with high rates of creation of accommodation space over peat *** petrology and coal facies analysis exhibits a permanently high water table within a forest swamp and mostly rheotrophic conditions,sometimes with connection to the ***-ing to paleoenvironmental reconstructions,it seems that coal layers may be thicker,with less sulfur(pyrite),but more clastic minerals and partings toward the western part of the *** these coal seams presently have low economic potential for the mining operation,partly due to great depth,this humic,high-volatile to medium-volatile bituminous coal may be suitable for exploration of coal bed methane resources.

关键词： Coal petrology Sedimentology Coal facies analysis Upper Triassic Nayband Formation Tabas Block

Role of incoherent pumping and Er^(3+) ion concentration on subluminal and superluminal light propagation in Er^(3+)-doped YAG crystal

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Chinese Physics B 2015年第1期24卷 269-274页

作者： Seyyed Hossein Asadpour H.rahimpour Soleimani Department of Physics University of GuilanRasht Iran

We study the absorption-dispersion process and group index of weak probe field in a four-level Er^3＋：YAG *** find that the Er^3＋ion concentration and incoherent pumping field can influence the absorption-dispersion process and group index of weak probe field. Moreover, our results show that Er^3＋ion concentration plays a major role in lasing without inversion and absorption with inversion.

关键词： Er^3+ion concentration incoherent pumping field superluminal

Er^(3+) ion concentration effect on transient and steady-state behavior in Er^(3+):YAG crystal

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Chinese Physics B 2014年第10期23卷 248-253页

作者： Asadpour Seyyed Hossein rahimpour Soleimani H Department of Physics University of Guilan

The effect of Er3＋ ion concentration on transient and steady-state behavior in 45-nm Er3＋：YAG crystal is investigated. It is shown that by changing the signal field, the coherent field and the concentration of Er3＋ ions in the crystal, the absorption, dispersion, and group index of the weak probe field can be adjusted. Also, it is found that the probe absorption occurs in the presence of population inversion and probe amplification is obtained in the absence of population inversion.

关键词： Er3+ ion concentration absorption dispersion group index

All-Optical Switching between Optical Bistability and Multistability via Exciton Spin Relaxation

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Communications in Theoretical Physics 2015年第1期63卷 71-76页

作者： Asadpour Seyyed Hossein rahimpour Soleimani Hamid Department of Physics University of Guilan

All-optical coherent control of optical bistability(OB) and optical multistability(OM) in the 4.8 nm Zn Se single-quantum well based on excitons and biexciton transitions is investigated. By applying a pair of phase-locked laser pulses all-optical coherent control can be obtained. Theoretical analysis with density matrix and Maxwell equations then yield the optical bistability and optical multistability. It is shown that by controlling the coherent and incoherent processes, the intensity threshold of OB and OM can be modified. Also, it is found that the switching between OB and OM or vice versa can be occurred for some controllable parameters.

关键词：光学双稳态全光开关激子跃迁自旋弛豫相干控制麦克斯韦方程单量子阱 ZnSe

Phase control of group-velocity-based biexciton coherence in a multiple quantum well nanostructure

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Chinese Physics B 2014年第10期23卷 139-146页

作者： Seyyed Hossein Asadpour H. rahimpour Soleimani Department of Physics University of Guilan

A double cascade-type four-level multiple-quantum-well-based exciton-biexciton transitions are proposed. The study is carried out on a 4.8-rim ZnSe single-quantum well which is embedded into ZnMgSSe cladding layers and pseudomor- phically grown by molecular beam epitaxy on a （0 0 1） GaAs substrate. It is displayed that the exciton spin relaxation and relative phases between applied fields can influence the transient and steady-state behaviors of absorption, dispersion, and group velocity of two weak probe and signal fields. Also, transient behaviors of electron population of different levels are discussed. It is found that the probe or signal amplification occurs in the absence of population inversion.

关键词： exciton-spin relaxation biexciton coherence relative phase between applied fields

A sensitivity analysis and multi-objective optimization to enhance ethylene production by oxidative dehydrogenation of ethane in a membrane-assisted reactor

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1879-1895页

作者： Ali Darvishi Ali Bakhtyari Mohammad Reza.rahimpour Department of Chemical Engineering Shiraz University

Owing to the importance of process intensification in the natural gas associated processes, the present contribution aims to investigate the production of an important natural gas downstream product in an improved ***, a membrane-assisted reactor for the oxidative dehydrogenation of ethane is presented. The presented system includes a membrane for axial oxygen dosing into the reaction side. Such a strategy would lead to optimum oxygen distribution along the reactor length and prevention of hot spot formation as well. A feasibility study is conducted by developing a validated mathematical model composed of mass and energy balance equations. The effects of various operating variables are investigated by a rigorous sensitivity ***, by applying the genetic algorithm, a multi-objective optimization procedure is implemented to obtain the optimum operating condition. Considerable increase in the ethane conversion and ethylene yield are the advancements of membrane-assisted oxidative dehydrogenation reactor working under the optimum *** than 30% increase in the ethane conversion is obtained. Furthermore, the ethylene yield is enhanced up to 0.45.

关键词：敏感分析优化过程反应堆氧化乙烷乙烯除氢生产

Phonon-dependent transport through a serially coupled double quantum dot system

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Chinese Physics B 2014年第5期23卷 510-515页

作者： M.Bagheri Tagani H.rahimpour Soleimani Department of Physics University of Guilan

Using Keldysh nonequilibrium Green function formalism and mapping a many-body electron-phonon interaction onto a one body problem, the electron transport through a serially coupled double quantum dot system is analyzed. The influence of the electron-phonon interaction, temperature, detuning, and interdot tunneling on the transmission coefficient and current is studied. Our results show that the electron-phonon interaction results in the appearance of the side peaks in the transmission coefficient, whose height is strongly dependent on the phonon temperature. We have also found that the inequality of the electron-phonon interaction strength in two dots gives rise to an asymmetry in the current-voltage characteristic. In addition, the temperature difference between the phonon and electron subsystems results in the reduction of the saturated current and the destruction of the step-like behavior of the current. It is also observed that the detuning can improve the magnitude of the current by compensating the mismatch of the quantum dots energy levels induced by the electron-phonon interaction.

关键词： quantum dot electron-phonon interaction Keldysh nonequilibrium Green function formalism,current-voltage characteristic

Impacts of vegetation over bedforms on flow characteristics in gravel-bed rivers

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Journal of Hydrodynamics 2019年第5期31卷 986-998页

作者： Hossein Afzalimehr Mohammad Reza Maddahi Jueyi Sui Majid rahimpour Department of Civil Engineering Iran University of Science and TechnologyTehranIran Department of Water Engineering Shahid Bahonar University of KermanKermanIran Environmental Engineering Program University of Northern British ColumbiaCanada

In the present study,among six gravel-bed river reaches,two natural gravel-bed river reaches with approximately similar bedforms and flow conditions have been found,one river reach with vegetation on bedforms and the other without vegetation on *** on field measurements,the impacts of vegetation over bedforms on flow characteristics have been *** velocity,Reynolds stress and turbulence intensity distributions over bedforms with vegetation have been compared with those over gravel bedforms without *** using the quadrant analysis,the dominant events of turbulent flow structures have been assessed for flows over gravel bedforms with vegetation and without *** show that the effect of vegetation enhances the anisotropy in turbulence and generates strong secondary currents,which lead to the occurrence of dip phenomenon at the stoss section and the crest of vegetated *** change of bed roughness from gravel bed to vegetated bed causes a development of a new boundary *** resulted in the different shape of velocity distributions over bedforms with vegetation from those over bedforms without vegetation,which can affect the lives of aquatic *** shear stress at downstream section of gravel bedform without vegetation is much higher than that of vegetated bedform,which shows that the erosion takes place from downstream of vegetated bedforms,while in the bare beds;the deposition is at downstream of *** is found that the presence of vegetation causes a chaotic distribution pattern of Reynolds shear stress,while it has more orderly pattern at the downstream section of gravel bedform without ***,the distribution of turbulence intensity in the lee side of vegetated bedform has a concave shape and in the stoss section,turbulence is generated in ejections and sweeps near the vegetation *** findings are significant to the practice of river ecological restoration.

关键词： Bedform Reynolds shear stress distribution turbulence intensity vegetation velocity profiles