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Journal of Central South University 2022年第11期29卷 3557-3580页

作者： M.salehi M.ESKANDARI M.YEGANEH Department of Materials Science and Engineering Faculty of EngineeringShahid Chamran University of AhvazAhvaz ***Iran

In the present study,the effects of microstructure,grain size,and texture after thermomechanical processing on the corrosion behavior of AISI 321 austenitic stainless steel(ASS)were *** as-received,coarse-grained steel((35±3)μm)was subjected to 20%,50%and 90%thickness reduction through cold rolling at liquid nitrogen temperature,followed by annealing at 750,950 and 1050℃for 15 *** occurred after annealing at 750℃,and with the increasing of annealing temperature to 950℃and 1050℃,secondary recrystallization(abnormal grain growth)and grain growth were *** results showed that,after 20%thickness reduction,corrosion resistance increased significantly(21.1 kΩ·cm^(2))compared with the as-received condition(3.9 kΩ·cm^(2))due to the enhancement ofγ-fiber and the creation ofΣ3 *** contrast,the corrosion resistance decreased with the increasing of thickness reduction to 90%during rolling,but still depicted higher corrosion resistance compared with the as-received *** annealing the 90%cold rolled(CR)specimens at 750 and 950℃,the corrosion resistance increased in comparison with the as-received sample as a result of the more uniform microstructure,appearance of Goss and brass texture components,and grain ***,significant grain growth((112±76)μm)followed by a non-uniform structure was observed after annealing at 1050℃and resulted in the lowest corrosion resistance(1.3 kΩ·cm^(2)).

关键词： corrosion texture microstructure thermomechanical processing stainless steel

Formation of Nano/Ultrafine Grains in AISI 321 Stainless Steel Using Advanced Thermo-Mechanical Process

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 499-504页

作者： Mohsen Golzar Shahri S.Rahman Hosseini Mehdi salehi Department of Materials Engineering Isfahan University of Technology Department of Materials Engineering Maleke-Ashtar University of Technology

Production of nano/ultrafine grains through deformation-induced martensite formation and its reversion to austenite in an AISI 321 stainless steel was studied. The repetitive cold rolling and subsequent annealing were conducted to obtain nanocrystalline structure. Heavy cold rolling （90% reduction） at ＋20 and -20 ℃ was carded out to induce the formation of α′-martensite from metastable austenitic material. The process was followed by annealing treatment at 700-900 ℃ for 0.5-30 min. Effects of process parameters, i.e., ＂reduction percentage,＂＂rolling temperature,＂＂annealing temperature＂ and ＂annealing time＂, on the microstructural development were considered. Microstructural evolutions were conducted using feritscope, X-ray diffractometer and scanning electron microscope. Hardness of the specimens was measured by Vickers method. Results revealed that the higher thickness reduction and lower rolling temperature provided more martensite volume fraction and further hardness. X-ray diffraction patterns and feritoscopic results indicated that saturated strain （εs） was reduced from 2.3 to 0.9 when temperature declined from ＋20 to -20 ℃. The smallest grain size （about 70 nm） was achieved in the condition of cold rolling at -20℃followed by annealing at 750 ℃for 5 min.

关键词： Austenitic stainless steel Deformation-induced martensite Nano/ultrafine grain structure Thermo-mechanical treatment

Color changes and drying kinetics modeling of basil seed mucilage during infrared drying process

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Information Processing in Agriculture 2022年第3期9卷 397-405页

作者： Ghazale Amini Fakhreddin salehi Majid Rasouli Faculty of Agriculture Bu-Ali Sina UniversityHamedanIran

The physicochemical properties and color of dried seed mucilage (gums) depend on thecondition and method of drying. So, in this study, the effects of infrared (IR) dryer systemparameters such as IR power (150, 250, and 375 W), distance of mucilage from lamp surface(4, 8, and 12 cm), mucilage thickness (0.5, 1.0, and 1.5 cm) on drying kinetics and colorindexes (L*a*b*) of basil seed mucilage (BSM) were examined in an IR dryer system. IR dry-ing kinetic of BSM was modeled using mathematical approach. Thus, experimental mois-ture ratio data were fitted to 8 various empirical models. It was found that Page model hasthe best fit to show the kinetic behavior and acceptably described the IR drying behavior ofBSM with the highest correlation coefficient values and the lowest standard error *** average effective moisture diffusivity (Deff) increased from 1.69×10^(-9)to 9.21×10^(-9)m^(2)/s with increasing lamp power from 150 W to 375 W, while it was decreased from7.93×10^(-9)to 2.65×10^(-9)m^(2)/s and 7.81×10^(-9)to 1.82×10^(-9)m^(2)/s with increasing the dis-tance of mucilage from 4 to 12 cm and the reduction of mucilage thickness from 1.5 to0.5 cm, respectively. The increasing in IR radiation power has a positive influence on thelightness (increasing L* index) of dried BSM and it reduced color changes index (DE) from13.04 to 11.51. The results showed that IR drying method has great industrial potential insaving processing time as well as energy with better maintenance of color and quality ofdried BSM.

关键词： Basil seed gum Drying kinetics Moisture ratio Page model

Dynamic Simulation of Volume Fraction and Density Solid Phase Effect on Phase Hold-Up in 3 Phase Fluidize Bed Column through CFD

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Engineering（科研） 2015年第1期7卷 31-35页

作者： mohammad Ali salehi Ali Basiry Department of Chemical Engineering University of Guilan Rasht Iran

The gas-liquid-solid fluidized bed has emerged in recent years as one of the most promising devices for three-phase operation. Selection and design is one of them in parameter in the performance of three phase system. This paper focuses on volume fraction and density effect on the phases hold-up in a 3 phase fluidize bed column containing liquid phase with 100 cm height and 20 cm diameter, in this case the solid phase with 0.15, 0.25, 0.35 volume fraction and density 2470, 3000, 4000, 5000 m3 dispersion into liquid phase and the gas phase enter the column through a sparger of 2 cm diameter with 0.02 m/s velocities. The results show as the solid phase volume fraction increases from 0.02 to 0.08 m/s. The gas hold-up decreases and solid hold-up increases. Solid phase density increases, so solid phase hold-up decreases and gas hold-up decreases.

关键词： Hydrodynamic Fluidized Bed Phases Hold-Up Three Phase Fluidized Bed Column CFD

Evaluation of proline, chlorophyll, soluble sugar content and uptake of nutrients in the German chamomile (Matricaria chamomilla L.) under drought stress and organic fertilizer treatments

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Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 886-891页

作者： Amin salehi Hamidreza Tasdighi Majid Gholamhoseini Agronomy and Plant Breeding Department Yasouj University Oil Seed Crops Department Seed and Plant Improvement Institute Agricultural Research Education and Extension Organization (AREEO)

Objective: To investigate the effect of drought stress and organic fertilizer on German chamomile(Matricaria chamomilla) nutrient uptake, leaf chlorophyll content and osmotic adjustment under field ***: This experiment was carried out through a randomized complete block design with a split factorial arrangement of treatments in three replications. The main plots were subjected to the following irrigation treatments: irrigation after 60, 90, 120, 150 and180 mm evaporation from Class A pan. The sub-plots were treated with three vermicompost doses(0, 5 and 10 t/ha).Results: Although drought stress reduced the nutrient percentages in the shoots, application of vermicompost enhanced the nutrient percentages, particularly when the plants were subjected to moderate to severe drought stress conditions. Moreover, the results of this study showed that the interaction between irrigation treatments and vermicompost rates on leaf chlorophyll content was significant. Comparison between the combined treatments indicated that under normal irrigation and moderate drought stress conditions chamomile plants received 5 and 10 t/ha vermicompost showed significantly higher leaf chlorophyll content comparing to the control ***: Totally, organic fertilization by vermicompost could partly alleviate the effect of drought stress on chamomile by increasing N, P and K uptake and leaf soluble sugar, especially in stressed treatments.

关键词： German chamomile(Matricaria chamomilla) Drought stress Osmotic adjustment Organic fertilizer Vermicompost

An MCDM approach to assessing influential factors on healthcare providers’safe performance during the COVID-19 pandemic:Probing into demographic variables

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Journal of Safety Science and Resilience 2023年第3期4卷 274-283页

作者： Vahid salehi Gholamreza Moradi Leila Omidi Elnaz Rahimi Faculty of Engineering and Applied Science Memorial University of NewfoundlandSt.John'sCanada Health and Environment Research Center Tabriz University of Medical SciencesTabrizIran Department of Occupational Health Engineering School of HealthTabriz University of Medical SciencesTabrizIran Department of Occupational Health Engineering School of Public HealthTehran University of Medical SciencesTehranIran

This study assessed the influence of occupational stress,individual resilience,and organizational resilience on the safety performance of healthcare providers during the COVID-19 *** variables including age,work experience,and gender were *** were collected from 344 healthcare providers employed at a teaching *** entropy method and the multi-criteria decision-making(MCDM)method were used to examine the influence of occupational stress,individual resilience,and organizational resilience on the safe performance of healthcare *** results of the entropy method showed that organizational resilience was the most influential factor in the safe performance of older healthcare *** contrast,individual resilience was the most significant factor in enhancing the safety performance of younger healthcare *** of work experience indicated that individual resilience was the most influential factor in the safe performance of less experienced healthcare ***-based analysis revealed that individual resilience had a major effect on the safety performance of both women and *** findings of this study could assist managers in improving the performance of the healthcare sector during pandemics by using and implementing resilience concepts at both the individual and organizational levels.

关键词： COVID-19 pandemic Safe performance Individual resilience Organizational resilience Demographic variables Entropy method

Ground states and excitation spectra of baryons in a non-relativistic model with the anharmonic potential

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Chinese Physics C 2013年第11期37卷 1-8页

作者： N.salehi H.Hassanabadi A.A.Rajabi Department of Basic Sciences Shahrood Branch Islamic Azad UniversityShahrood Iran Physics Department Shahrood University of Technology P.O.Box ***-316Shahrood Iran

： In this work the mass spectra for some of the baryon resonances of the particle data group with three and four star status are obtained, and a unified description of the ground states and excitation spectra of baryons are provided in the framework of a non-relativistic potential model. For this goal we have analytically solved the radial SchrSdinger equation for three identical interacting particles with the anharmonic potential by using the Ansatz method and then we have calculated the baryon resonances spectrum by using the G/irsey Radicati mass formula （GR） and with generalized Giirsey Radicati mass formula （GGR）. The results of our model show that the calculated masses of baryon resonances by using the generalized Giirsey Radicati mass formula are found to be in good agreement with the tabulations of the Particle Data Group. The overall good description of the spectrum which we obtain shows that our model can also be used to give a fair description of the energies of the excited multiples up to 3 GeV mass and negative-parity resonance. Moreover, we have shown that our model reproduces the position of the Roper resonance of the nucleon.

关键词： baryons resonances spectrum anharmonic potential non-relativistic quark models

Chitosan/polyethylene glycol impregnated activated carbons： Synthesis, characterization and adsorption performance

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 575-585页

作者： Ehsan salehi Fereshteh Soroush Maryam Momeni Aboulfazl Barati Ali Khakpour . Department of Chemical Engineering Faculty of Engineering Arak University Arak 38156-8-8349 Iran.. Department of Electrical Engineering Faculty of Engineering Arak University Arak 38156-8-8349 Iran.. Arian Fan Azma Company Tehran Iran

Novel modified activated carbons （ACs） with enhanced adsorptive properties were obtained coating by chitosan （CS）, polyethylene glycol （PEG） and blends of the two polymers （0：1, 1：0, 1：1, 1：2 and 2：1 wt/wt） on ACs by an impregnation technique. The adsorption perfor- mances of the pristine, acidified and polymer-impregnated ACs were studied using methylene blue as a model adsorbate. The adsorbents were characterized using Four- ier transform infrared spectroscopy, scanning electron microscopy and abrasion hardness tests. The average coating thicknesses were between 10 to 23 microns. The pore sizes, pore densities and pore capacities of the activated carbons increased as the wt-% PEG in the coating increased. The highest adsorption capacity （424.7 mg/g） was obtained for the chitosan-coated ACs and this adsorption was well described by the Langmuir isotherm model. The kinetic results were best described by the pseudo-second-order kinetic model. The highest rate constant was obtained with the ACs modified with the CS：PEG （2：1） coating and this result was almost 2.6 times greater than that of the unmodified ACs. The CS/PEG impregnated ACs also displayed superior hardness （-90%）, compared to unmodified ACs （-85%）. Overall the chitosan had a greater effect on improving adsorption capacity whereas the polyethylene glycol enhanced the adsorption rate.

关键词： carbon biocomposites impregnation chito-san polyethylene glycol image processing

Optimizing consolidation behavior of Al 7068-TiC nanocomposites using Taguchi statistical analysis

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Transactions of Nonferrous Metals Society of China 2015年第8期25卷 2499-2508页

作者： Amin AZIMI Ali SHOKUHFAR Omid NEJADSEYFI Hamid FALLAHDOOST Saeid salehi Young Researchers and Elite Club South Tehran Branch Islamic Azad University Advanced Materials and Nanotechnology Research Center Department of Mechanical EngineeringK.N.Toosi University of Technology Department of Engineering Karaj Branch Islamic Azad University

The fabrication of high strength Al 7068？5%TiC （mass fraction） nanocomposite was studied by mechanical alloying and hot pressing routes. Considering densification importance and grain growth effects, hot pressing process conditions for producing bulk nanocomposite were optimized using statistical Taguchi method based on compressive strength achievement. The Taguchi results indicate that 30 min hot pressing under pressure of 500 MPa at 385 °C provides high compressive strength and hardness of 938 MPa and HV 265, respectively. More interestingly, analysis of variance proves that the applied pressure is the most influential factor for hot pressing of the nanocomposite. The contribution percentages of factors in hot pressing terms are as follows： applied pressure （61.3%）, exposed temperature （29.53%） and dwelling hot pressing time （4.49%）.

关键词： Al 7068-TiC nanocomposite hot pressing mechanical alloying Taguchi method mechanical properties

Efficient energy absorption of functionally-graded metallic foam-filled tubes under impact loading

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Transactions of Nonferrous Metals Society of China 2021年第1期31卷 92-110页

作者： M.salehi S.M.H.MIRBAGHERI A.JAFARI RAMIANI Department of Materials and Metallurgical Engineering Amirkabir University of TechnologyTehran 15875-4413Iran

The deformation behavior and crashworthiness of functionally-graded foam-filled tubes(FGFTs)under drop-weight impact loading were *** cell aluminum,A356 alloy and zinc foams fabricated by the liquid state processing were used as axial grading fillers for the manufacture of single-layer and multilayer structures with different *** results indicate that the deformation of multilayer foam filled tubes initiates from the low-strength components,and then propagates in the high-strength components through the gradual increment of *** use of more A356 alloy and aluminum foam layers provides greater specific energy absorption(SEA)for the graded structures,whereas the high-strength zinc foam has no positive effect on the crash *** progressive collapse of graded structures consisting of the aluminum and A356 alloy foams occurs in a symmetric mode under quasi-static and drop-weight impact ***,the zinc foam causes a combination of symmetric and extension modes as well as greater localized deformation under dynamic loading and greater local rupture in quasi-static loading *** Al−A356 foam-filled tubes with a combination of the highest SEA(10 J/g)and the lowest initial peak stress(σmax of 10.2 MPa)are considered as the best lightweight crashworthy structures.

关键词： functionally-graded foam-filled tube drop-weight impact deformation behavior specific energy absorption crashworthiness