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Transactions of Nonferrous Metals Society of China 2021年第9期31卷 2626-2650页

作者： Mahmoud ABBASI Behrouz bagheri Farzaneh SHArIFI Faculty of Engineering University of KashanKashanIran Department of Mining and Metallurgy Amirkabir University of TechnologyTehranIran School of Mechanical and Materials Engineering Washington State UniversityPullmanUSA

A two-dimensional cellular automaton(CA)model was utilized to analyze the effect of mechanical vibration on microstructure evolution of AZ91 alloy during friction stir welding(FSW).The simulated results,namely grain topology,grain size distribution,average grain size,and also the dynamic recrystallization(DrX)fraction were compared with measured *** adequate comparability between FEM and experimental data shows that the CA method can be applied to the analysis of the microstructure progression during the friction stir welding of AZ91 *** is concluded that the dislocation density during the friction stir vibration welding(FSVW)is higher than that in the FSW process and the process of nucleation and grain growth is faster for samples during FSVW compared to *** grain size modification and DrX phenomenon with various vibration frequencies were also simulated in detail during *** is found that vibration makes nucleation start earlier and decreases the proportion of the incubation period and the percentage of recrystallization as vibration frequency improves.

关键词： friction stir welding vibration simulation grain size dynamic recrystallization cellular automaton model

Quantum speed limit time and entanglement in a non-Markovian evolution of spin qubits of coupled quantum dots

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Chinese Physics B 2020年第12期29卷 244-250页

作者： M.bagheri Harouni Department of Physics University of IsfahanHezar Jerib St.Isfahan 81764-73441Iran Department of Physics Quantum Optics GroupUniversity of IsfahanHezar Jerib St.Isfahan 81764-73441Iran

Quantum speed limit time and entanglement in a system composed of coupled quantum dots are *** excess electron spin in each quantum dot constitutes the physical system(qubit).Also the spin interaction is modeled through the Heisenberg model and the spins are imposed by an external magnetic *** into account the spin relaxation as a non-Markovian process,the quantum speed limit and entanglement evolution are *** findings reveal that increasing the magnetic field leads to the faster quantum *** addition,the temperature increment causes the longer quantum speed limit time as well as the entanglement degradation.

关键词： quantum speed limit time quantum entanglement open quantum systems quantum dots

Essential oil composition of two Scutellaria species from Iran

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Journal of Traditional Chinese Medical Sciences 2019年第3期6卷 244-253页

作者： Gharari Zahra bagheri Khadijeh Danafar Hossein Sharafi Ali Department of Plant Production and Genetics Faculty of AgricultureUniversity of ZanjanZanjanIran School of Pharmacy Zanjan University of Medical SciencesZanjanIran Zanjan Applied Pharmacology research Center School of PharmacyZanjan University of Medical SciencesZanjanIran Zanjan Pharmaceutical Biotechnology research Center Zanjan University of Medical SciencesZanjanIran

Objective:Medicinal plants Scutellaria multicaulis and Scutellaria bornmuelleri belong to the Scutellaria genus and Lamiaceae family,and are widely used in traditional Iranian *** study aims to characterize promising bioactive phytochemicals found in the aerial parts of *** and ***:Accordingly,volatile oils were obtained by hydrodistillation of *** and *** leaves and stems,and then analyzed by gas chromatographyemass spectrometry(GC/MS).results:A total of 88 components,representing 92.4%of the oil(oil yield determined to be 0.53%,v/w),were identified in the essential oils of *** main group was sesquiterpene hydrocarbons(24%),with a-himachalene(7.2%),a-longipinene(6.8%),and a-copaene(3.2%)as the main components.A total of 89 chemicals,representing 83.2%of the essential oil(oil yield determined to be 0.31%,v/w),were detected in the essential oil of *** main components were steroids,such as 14-b-H-pregna(32.9%),hydrocarbons(22.5%),sesquiterpenes(11.4%),and monoterpenes(4.6%),which were considered minor *** contents of sesquiterpene and monoterpene hydrocarbons present in *** and *** were 24%and 7.1%,***,the contribution of oxygenated monoterpenes(4%)and sesquiterpenes(4.3%)in both species was less than 5%.Conclusion:As the first report on the chemical composition of *** and ***,this study showed that the major compounds were steroids and sesquiterpenes.

关键词： 14-b-H-Pregna GC/MS a-himachalene a-Longipinene Scutellaria

Surface potential uniformity and sensitivity of large-area PTFE electret discs of different thicknesses produced by a modified corona poling rotating system for dosimetry applications

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Journal of Advanced Dielectrics 2019年第6期9卷 52-62页

作者： A.Komeijani H.bagheri B.Shekarchi AJA radiation Sciences research Center(ArSrC)Science and research Branch AJA University of Medical Sciences Tehran Iran

In this study,large-area(6-cm diameter)Teflon polytetrafluoroethylene(PTFE)discs of different thicknesses(0.2-,0.5-and 1-mm)were negatively and positively charged by using the“modified single point-to-plane corona poling rotating system”.The effects of some crucial parameters of the PTFE disc as well as the modified corona poling rotating system on the PTFE surface potential uniformity such as.(a)PTFE disc thickness,(b)PTFE disc polarity and(c)needle-to-PTFE disc distance were successfully ***,closer needle-to-PTFE disc distance,positive charging mode and thinner PTFE disc provided a better PTFE surface potential ***,the effects of PTFE charge polarity and needle distance on the electrostatic charge potential uniformity were much more remarkable in comparison with the effects of PTFE ***,the surface potential distribution profiles of charged PTFE discs were totally flat and independent of the PTFE thickness at 5-and 13-mm needle distances for the negative and positive charging modes,*** the optimized charging conditions,large-area PTFE electret disc(0.5-mm-thick)with positive uniform surface charge potential especially at the edges up to1.8 kV with stability up to 77 days studied was produced by applying a new multiple heat treatment protocol to the PTFE disc for radon *** also observed in this study,the sensitivity of PTFE electret dosimeters to a defined radon gas concentration increases as the PTFE thickness ***,0.5-mm-thick PTFE electret disc produced was selected to be used as a high quality electret dosimeter with acceptable and superior parameters for different applications in particular medium-term radiation dosimetry in both low and high dose rate ionizing radiation fields.

关键词： PTFE electrets dielectric polarization surface charge uniformity and stability electrostatic discharges and measurements dosimetry

Study of structural,electrical and optical properties of vanadium oxide condensed films deposited by spray pyrolysis technique

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Advances in Manufacturing 2013年第4期1卷 320-328页

作者： M.Mousavi A.Kompany N.Shahtahmasebi M.M.bagheri-Mohagheghi Department of Physics Ferdowsi University of Mashhad Nanoscience Center Ferdowsi University of Mashhad School of Physics Damghan University

Vanadium oxides condensed films are prepared on glass substrates, using spray pyrolysis （SP） technique. The effects of substrate temperature, vanadium concentra- tion in initial solution and the solution spray rate on the nano-structural, electrical, and optical properties of depos- ited films were investigated. Characterizations of the sam- ples were performed using X-ray diffraction （XrD）, scanning electron microscopy （SEM）, and UV-Vis spec- troscopy methods. The type and concentration of the charge carriers were determined and measured by Hall effect experiment. XrD patterns showed that the prepared films had polycrystalline structure, mostly tetragonal fl-V205 and V409 phases with the preferred orientation along （200） direction. The Hall effect experiment revealed that all samples were n-type, except the ones deposited at substrate temperatures Tsub ： 300 ~C and Tsub = 450 ~C, vanadium concentration 0.1 mol/L and solution spray rate 10 mL/min. The charge carrier concentrations obtained were in the range 1016-1018 cm-3. The lowest sheet resistance （r~） was obtained for the samples prepared at T^ub = 450 ~C, vana- dium concentration 0.05 mol/L and solution spray rate 10 mL/min. It was also found that the optical transparency of the samples changed from 20% to 75% and the optical bandgap of the samples was from 2.22 eV to 2.58 eV, depending on the deposition conditions.

关键词： Vanadium oxide Thin films Opticalproperties Spray pyrolysis

Estimation of Formation Enthalpies of Organic Pollutants from a New Structural Group Contribution Method

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Chinese Journal of Chemical Engineering 2013年第6期21卷 644-653页

作者： Mehdi bagheri Afshin Bakhtiari Masoume Jaberit Young researchers Club Islamic Azad University Science and Research Branch Tehran *** Iran Tehran Naftoon Arya Eng. Co. Jahanmehr St. Fatemi Sq. Tehran *** iran Department of ChemicalEngineering University of Tehran Tehran *** Iran

Chemical stability and reactivity of organic pollutants is dependent to their formation enthalpies. The main objective of this study is to provide simple straightforward strategy for prediction of the formation enthalpies of wide range organic pollutants only from their structural functional groups. Using such an extended dataset cornprising 1694 organic chemicals from 77 diverse material classes benefits the generalizability and reliability of the study. The new suggested collection of 12 functional groups and a simple linear regression lead to promising statis- tics of r2= 0.958, Q2 =0.956, and AEE= 57 ***1-1 for the whole dataset. Moreover, unknown experimental formation enthalpies for 27 organic pollutants are estimated by the presented approach. The resultant model needs no technical software/calculations, and thus can be easily applied by a non-specialist user.

关键词： organic pollutants enthalpy of formation slructural group contribution (SGC) molecular basedmodehng

Investigation of quality factor frequency content in vertical seismic profile for gas reservoirs

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Petroleum research 2021年第1期6卷 57-65页

作者： Ehsan Larki Abbas Ayatizadeh Tanha Amirhossein Parizad Bahram Soltani Soulgani Dr Hassan bagheri National Iranian Drilling Company Well Logging DepartmentAhwazIran Petroleum University of Technology Ahwaz Faculty of Petroleum EngineeringAhwazIran Sahand University of Technology Petroleum Exploration EngineeringTabrizIran Department of Petroleum Engineering Ahwaz Faculty of Petroleum EngineeringPetroleum University of Technology(PUT)AhwazIran

Since long ago, indirect study of the underground layers properties has been interesting to *** method for this study was seismography which gained great interest besides other tools due to thedifferent identity of waves and energy attraction phenomena in different layers. Vertical seismic profiling(VSP) is considered as a valuable method in oil and gas exploration. This method is used to estimate therock properties in a well. In seismic operations elastic waves are sent down to the underground. Part ofthe waves’ energy is reflected after passing through the earth layers and are received by receivers on theground level. The received data determine the situation of the underneath layers after being processed,and one of the most important applications of seismic data is in the oil and gas exploration field. Qualityfactor is one of the most important seismic detectors that shows itself apparently in VSP data results. Themost substantial purpose of this study is to investigate the frequency content of the quality factor.

关键词： Vertical seismic profiling(VSP) Sonic log Seismic waves Quality factor rock properties Gas reservoir

Understanding the attitudes and practices of paddy farmers for enhancing soil and water conservation in Northern Iran

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International Soil and Water Conservation research 2016年第4期4卷 260-266页

作者： Dariush Ashoori Asghar.bagheri Mohammad Sadegh Allahyari Anastasios Michailidis Department of Water Engineering and Agricultural Management Faculty of Agricultural Technologies and Natural ResourcesUniversity of Mohaghegh ArdabiliArdabilIran Department of Agricultural Management Rasht BranchIslamic Azad UniversityRashtIran Aristotle University of Thessaloniki School of AgricultureForestry and Environmental SciencesFaculty of AgricultureDepartment of Agricultural EconomicsLaboratory of Agricultural Extension and Rural Sociology54124ThessalonikiGreece

The objective of this paper was to identify the factors affecting rice growers’attitudes and practices towards water and soil conservation in the Fumanat Plain of Guilan Province,*** were collected through a survey questionnaire addressing a cross section of 400 rice growers of the Fumanat Plain in four *** were analyzed using both summary statistics and multivariate statistical procedures while content validity of the statements was first determined by a group of experts of water and soil *** was found that more than 23% of the variance of attitudes towards water and soil conservation could be determined by a linear combination of variables included in a regression *** the factors affecting rice growers’attitudes is suggested as a way of integrating rice cultivation into rural *** a practical point of view,the above mentioned implications are of great importance generally for society,policy makers and related economic sectors.

关键词： Attitude Multiple regression analysis rice growers Water and soil conservation

Effects of pin angle and preheating on temperature distribution during friction stir welding operation

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Transactions of Nonferrous Metals Society of China 2013年第9期23卷 2708-2713页

作者： r. KEIVANI B. bagheri F. SHArIFI M. KETABCHI M. ABBASI Department of Material Engineering Islamic Azad University (Science and Research Branch) Department of Mining and Metallurgy Amirkabir University of Technology Faculty of Engineering University of Kashan

Friction stir welding （FSW） is applied extensively in industry for joining of nonferrous metals especially aluminum. A three-dimensional model based on finite element analysis was used to study the thermal characteristic of copper C I 1000 during the FSW process. The model incorporates the mechanical reaction of the tool and thermo-mechanieal characteristics of the weld material, while the friction between the material and the probe and the shoulder serves as the heat source. It was observed that the predicted results about the temperature were in good compatibility with the experimental results. Additionally, it was concluded that the numerical method can be simply applied to measuring the temperature of workpiece just beneath the tool. The effects of preheating temperature and pin angle on temperature distribution were also studied numerically. The increase of pin angle enhances the temperature around the weld line, but preheating does not affect temperature distribution along the weld line considerably.

关键词： friction stir welding simulation temperature distribution pin angle preheating

Prediction of new perforation intervals in a depleted reservoir to achieve the maximum productivity: A case study of PNN logging in a cased-well of an Iranian oil reservoir

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Petroleum 2020年第2期6卷 170-176页

作者： Saeed Zaker Shahab mohamadi nafchi Mahdi rastegarnia Soheila bagheri Ali Sanati Amir Naghibi Islamic Azad University Science and Research BranchTehranIran Islamic Azad University Central BranchTehranIran Head of Petrophysics Section Petro Pardazesh Aria CompanyTehranIran Senior Petrophysicist OTS CompanyTehranIran School of Petrochemical and Petroleum Engineering Hakim Sabzevari UniversitySabzevarIran Senior Petrophysicist Iranian Central Oil Field CompanyTehranIran

Pulsed neutron-neutron(PNN)logging is based on emitting neutrons into the near-wellbore zone and computing the neutron count decay due to scattering and *** main application of this logging tool is to determine the current oil saturation and to detect channeling in perforated and non-perforated intervals behind the *** interpretation of the results obtained from PNN logging enables engineers to predict new perforation intervals in depleted *** study examines the application of PNN logging in a well located in one of Iranian oil *** interpretation procedure is described step by *** principle of the PNN logging and the specifications of the tool are discussed and the applications of PNN logging in evaluation of oil saturation,identification of water flooded zones and prediction of potential perforating zones are *** is also investigated between all layers,good and poor oil zones are characterized based on the calculated oil saturations and new perforation intervals are suggested with the aim to boost oil production from the *** results of this study show that zones 1 to 5 having low oil saturations,are interpreted as depleted oil *** 6 to 8 are interpreted as good oil zones having high potential to produce *** 9 is interpreted as a water zone.

关键词： Pulse neutron-neutron(PNN)logging Sigma value remaining oil saturation Conventional logging Perforation intervals Depleted reservoir