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Frontiers of Chemical Science and Engineering 2021年第2期15卷 450-459页

作者： hossein Abdolmohammad-Zadeh Arezu Salimi Analytical Spectroscopy Research Lab Department of ChemistryFaculty of SciencesAzarbaijan Shahid Madani UniversityTabriz ***Iran

In this research,an eco-friendly magnetic adsorbent based on Fe_(3)O_(4)/salicylic acid nanocomposite was fabricated using a facile one-pot co-precipitation *** crystalline and morphological characterization of the prepared nanocomposite was performed by field emission scanning electron microscopy,X-ray diffraction,and Fourier transform infrared *** nanocomposite was employed as a magnetic solid-phase extraction agent for separation of Cd(II)ions from synthetic *** experimental factors affecting the extraction efficiency were investigated and *** elution with acetic acid(pH 3.5),the pre-concentrated analyte was quantified by flame atomic absorption *** optimal conditions,a linear calibration graph was achieved in the concentration range of 0.2–30 ng·mL^(−1) with a determination coefficient(R^(2))of *** detection limit,the enhancement factor,inter-and intra-day relative standard deviations(for six consecutive extractions at the concentration level of 10 ng·mL^(−1))were 0.04 ng·mL^(−1),100,2.38%and 1.52%,*** evaluate the accuracy of the method,a certified reference material(NIST SRM 1643e)was analyzed,and there was a good agreement between the certified and the measured *** was successfully utilized to determine cadmium in industrial wastewater samples and the attained relative recovery values were between 96.8%and 103.2%.

关键词： cadmium magnetic solid-phase extraction Fe_(3)O_(4)nanoparticles Fe_(3)O_(4)/salicylic acid nanocomposite flame atomic absorption spectrometry

Finding buckling points for nonlinear structures by dynamic relaxation scheme

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 23-61页

作者： Mohammad REZAIEE-PAJAND hossein ESTIRI Civil Engineering Department Ferdowsi University of MashhadMashhad 91775-1111Iran

Dynamic Relaxation Method(DRM)is an explicit approach for solving the simultaneous systems of *** this tactic,the fictitious mass and damping are added to the static governing equations,and an artificial dynamic system is *** using DRM for nonlinear analysis,the structural static equilibrium path is *** outcome is extremely valuable,since it leads to the behavior of *** the finding related to the structural static path are the critical and buckling points for nonlinear *** this paper,a new way for calculating the load factor is proposed by setting the external work *** the dynamic relaxation scheme with external work technique has not been formulated so *** all incremental-iterative methods,the load factor increment sign should be determinated by extra *** sign leads to increase or decrease of the load *** is worth emphasizing that sign of the load factor increment changes at the load limit ***,the sign determinations are required in the common work control *** disadvantages are eliminated in the proposed *** fact,the suggested load factor depends only on the Dynamic Relaxation(DR)fictitious ***,all DR calculations are performed via vector ***,the load factor is calculated only by one formula,and it has the same relation in the all solution *** contrast to the arc length techniques,which requires the sign determined,the proposed scheme does not need any sign *** is shown that author’s technique is quicker than the other dynamic relaxation *** prove the capability and efficiency of the presented scheme,several numerical tests are *** results indicate that the suggested approach can trace the complex structural static paths,even in the snap-back and snap-through parts.

关键词： load factor external work dynamic relaxation static equilibrium path large displacement

Finite element simulation for elastic dislocation of the North-Tehran fault:The effects of geologic layering and slip distribution for the segment located in Karaj

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Frontiers of Structural and Civil Engineering 2022年第4期16卷 533-549页

作者： Pooya ZAKIAN hossein ASADI HAYEH Department of Civil Engineering Faculty of EngineeringArak UniversityArak 38156-88349Iran

The present study uses the finite element method for simulating the crustal deformation due to the dislocation of a segment of the North-Tehran fault located in the Karaj metropolis *** this regard,a geological map of Karaj that includes the fault segment is utilized in order to create the geometry of finite element ***,finite element analysis of homogeneous counterpart of the fault’s domain with two different sections was performed,and the results were compared to those of Okada’s analytical *** fault was modeled with the existing heterogeneity of the domain having been *** influences of both uniform and non-uniform slip distributions were ***,three levels of simplification for geometric creation of geological layers’boundaries were defined in order to evaluate the effects of the geometric complexity of the geological layering on the displacement responses obtained with the finite element *** addition to the assessment of slip distribution,layering complexity and heterogeneity,the results demonstrate both the capability and usefulness of the proposed models in the dislocation analysis for the Karaj segment of North-Tehran fault.

关键词： finite element method fault dislocation slip distribution the North-Tehran fault heterogeneity geological layering

Effect of residual structural strain caused by the addition of Co3O4 nanoparticles on the structural, hardness and magnetic properties of an Al/Co3O4 nanocomposite produced by powder metallurgy

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 384-390页

作者： Seyed Rahim Kiahosseini hossein Ahmadian Department of Engineering Damghan Branch Islamic Azad University

Al composites are of interest due to their appropriate ratio of strength to *** our research,an Al/Co3O4 nanocomposite was generated using a sintering *** powders of Al with various Co3O4 nanoparticle contents(0 wt%,0.5 wt%,1.0 wt%,1.5 wt%,2.0 wt%,and2.5 wt%)were first blended using planetary milling for 30 min,and compressed in a cylindrical steel mold with a diameter of 1 cm and a height of5 cm at a pressure of 80 *** samples were evaluated with X-ray diffractometry(XRD),scanning electron microscopy(SEM),Vickers hardness,and a vibrating sample magnetometer(VSM).Although the crystallite size of the Al particles remained constant at 7–10 nm,the accumulation of nanoparticles in the Al particle interspace increased the structural tensile strain from 0.0045 to 0.0063,the hardness from HV 28 to HV 52 and the magnetic saturation from 0.044 to 0.404 emu/g with an increase in Co3O4 nanoparticle content from 0 wt%to 2.5 wt%.

关键词： Residual strain Vickers hardness vibrating sample magnetometer scanning electron microscopy

An Alternative Technique for Compounding and Fabrication of Lithium Ion Conductive PVB Films with Enhanced Thermal Properties and Electrochromic Performance

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Chinese Journal of Polymer Science 2022年第10期40卷 1213-1222,I0009页

作者： Mohammad hossein Azarian Jatuphorn Wootthikanokkhan Materials Technology Program School of EnergyEnvironment and MaterialsKing Mongkut's University of Technology ThonburiBangkok 10140Thailand

This research concerns the development of lithium ions conductive electrolyte from poly(vinyl butyral)(PVB)resin for use as a special interlayer film in electrochromic *** obtain the final PVB film with high ionic conductivity and thermal stability,a masterbatch was firstly prepared by mixing of PVB resin with lithium salt(LiClO_(4))and additives in an aqueous ethanol *** this,the dried masterbatch were converted into final films by an extrusion *** this study,PVB film with the highest ionic conductivity value of 4.85×10^(-6) was obtained when the masterbatch was diluted with the neat PVB resin at the weight ratio of 2:1 in the extruder prior to *** results from cyclic voltammetry over 100 cycles,showed that performance of the electrochromic device(ITO/WO_(3)/PVB electrolyte/ITO)fabricated by using the above PVB film is stable and *** overall,this work demonstrates that ion conductive PVB films with compromised ionic conductivity and thermal stability can be prepared via an extrusion process without the need to modify chemical structure of *** was carried out through the masterbatch approach,by introducing (LiClO_(4)) salts into the plasticized PVB via a solution mixing process prior to converting it into a final film via the extrusion process.

关键词： Ionic conductivity Poly(vinyl butyral) Masterbatch mixing Solid polymer electrolyte Electrochromic glass Safety glass

Mechanical characterization of Mg-B4C nanocomposite fabricated at different strain rates

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 252-263页

作者： Gholam hossein Majzoobi Kaveh Rahmani Mechanical Engineering Department Bu-Ali Sina University

Magnesium has wide application in *** main purpose of this investigation was to improve the properties of magnesium by reinforcing it using B4C *** reinforced nanocomposites were fabricated using a powder compaction technique for 0,1.5vol%,3vol%,5vol%,and 10vol% of *** compaction was conducted using a split Hopkinson bar(SHB),drop hammer(DH),and Instron to reach different compaction loading *** compressive stress–strain curves of the samples were captured from quasi-static and dynamic tests carried out using an Instron and split Hopkinson pressure bar,*** revealed that,to achieve the highest improvement in ultimate strength,the contents of B4C were 1.5vol%,3vol%,and 3vol% for Instron,DH,and SHB,*** results also indicated that the effect of compaction type on the quasi-static strength of the samples was not as significant,although its effect on the dynamic strength of the samples was *** improvement in ultimate strength obtained from the quasi-static stress–strain curves of the samples(compared to pure Mg)varied from 9.9% for DH to 24% for *** dynamic strength of the samples was improved(with respect to pure Mg)by 73%,116%,and 141%for the specimens compacted by Instron,DH,and SHB,*** improvement in strength was believed to be due to strengthening mechanisms,friction,adiabatic heating,and shock waves.

关键词： powder compaction B4C magnesium strain rate ultimate strength sintering

A simulation study on p-doping level of polymer host material in P3HT:PCBM bulk heterojunction solar cells

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Chinese Physics B 2017年第4期26卷 508-512页

作者： hossein Movla Mohammad Babazadeh Azar Aytash Co. Technology IncubatorUniversity of TabrizTabrizIran

In this study,we investigate the influence of doping on the charge transfer and device characteristics parameters in the bulk heterojunction solar cells based on poly（3-hexylthiophene）（P3HT） and a methanofuUerene derivative（PCBM）.Organic semiconductors are also known to be not pure and they have defects and impurities,some of them are being charged and act as p-type or n-type *** of the solar cell characteristics parameters versus the p-doping level have been done at three different n-dopings（N_d） that consist of 5 × 10^（17） cm^（-3）,10^（18） cm^（-3）,and 5 × 10^（18） cm^（-3）.We perform the analysis of the doping concentration through the drift-diffusion model,and calculate the current and voltage doping *** find that at three different n-dopant levels,optimum p-type doping is about N_p = 6 × 10^（18） cm^（-3）.Simulation results have shown that by increasing doping level,V_（oc） monotonically increases by *** efficiency reaches its maximum at somewhat higher doping as FF has its peak at N_p = 3 × 10^（18） cm^（-3）.Moreover,this paper demonstrates that the optimum value for the p-doping is about N_p = 6 × 10^（18） cm^（-3） and optimum value for n-dopant is N_d = 10^（18） cm^（-3）,*** simulated results confirm that doping considerably affects the performance of organic solar cells.

关键词： organic photovoltaics charge transport doping finite difference method

Secure Resource Allocation in Device-to-Device Communications Underlaying Cellular Networks

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China Communications 2022年第8期19卷 149-167页

作者： hossein Ghavami Bahareh Akhbari Faculty of Electrical Engineering K.N.Toosi University of TechnologyTehranIran

With increasing the demand for transmitting secure information in wireless networks,deviceto-device(D2D)communication has great potential to improve system *** a well-known security risk is eavesdropping in D2D communication,ensuring information security is quite *** this paper,we first obtain the closed-forms of the secrecy outage probability(SOP)and the secrecy ergodic capacity(SEC)for direct and decodeand-forward(DF)relay *** results are presented to verify the theoretical results,and these results show the cases that the DF relay mode improves security performance compared to the direct mode at long distances between the transmitter and receiver ***,we look into the optimization problems of secure resource allocation in D2D communication to maximize the SEC and to minimize the SOP by considering the strictly positive secrecy capacity constraint as a mixed-integer non-linear programming(MINLP)*** the continue,we convert the MINLP to convex ***,we solve this program with a dual method and obtain an optimal solution in the direct and DF relay modes.

关键词： D2D communication Secrecy ergodic capacity Secrecy outage probability Secrecy resource allocation Convex optimization

Basin Analysis and Paleogeography of the Zagros Foreland Basin during the Maastrichtian,High Zagros Basin,Iran

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Journal of Earth Science 2024年第5期35卷 1527-1545页

作者： hossein Ghanbarloo Amrollah Safari Department of Geology University of IsfahanIsfahan 81746-73441Iran

A sedimentological investigation was carried out to reconstruct the paleogeography of the Zagros Foreland *** on the study of more than 1000 rock samples,nine carbonate microfacies and three terrigenous facies were *** study reveals that the Maastrichtian succession was deposited in a widespread homoclinal ramp in the High Zagros ***(Gandom Kar area),two(Ardal area),seven(Gardbishe area),five(Shirmard area),two(Kuh-e-Kamaneh area),three(Kuh-e-Balghar area),and six(Murak area)of depositional sequences(3rd order)were *** thickness of the lowstand systems tract(LST)due to activities of local faults and subsidence in the southeast is more than in the central and northwest of the High Zagros Basin during the Early and Early Middle *** the Middle Maastrichtian,the shallow and deep marine deposits were formed during the transgressive systems tract(TST)and highstand systems tract(HST)in this basin and the rate of subsidence in the center of this basin(Gardbishe area)is higher than in other areas and the platform was drowned in this *** falling relative sea-level due to activities of local faults led to that marine deposits were absent in all parts of the High Zagros Basin(except the south part)during the Late *** studies on the Zagros Basin during the Late Campanian-Maastrichtian showed the following results:shallow marine environments were developed in the southeast of this basin,and the turbidite,delta,and fluvial environments in the northwest were developed more than in other areas.

关键词： Maastrichtian deposits local fault depositional sequences Neotethys Basin Inception Foreland Basin Late Cretaceous basin analysis paleogeography

Plant diversity of Hyrcanian relict forests:An annotated checklist,chorology and threat categories of endemic and near endemic vascular plant species

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Plant Diversity 2022年第1期44卷 39-69页

作者： Atefeh Ghorbanalizadeh hossein Akhani Halophytes and C4 Plants Research Laboratory Department of Plant SciencesSchool of BiologyCollege of SciencesUniversity of TehranP.O.Box 14155-6455TehranIran

In this paper a critical annotated checklist of 256 endemic and near endemic species belonging to 152 genera and 50 families of flowering plants known from Hyrcanian relict forests is *** maps of taxa,elevational range,number of known records,chorotypes,life forms,IUCN threat categories and habitat types are also *** chorotypes are categorized into eight main patterns:1)the Omni-Hyrcanian pattern(OH),2)West Hyrcanian pattern(WH),3)Manjil-Rudbar pattern(MR),4)Central Hyrcanian pattern(CH),5)Central and East Hyrcanian pattern(CEH),6)East Hyrcanian pattern(EH),7)Alborz-Hyrcanian pattern(AH),and 8)Euxino-Hyrcanian pattern(XH).The richness and distribution maps were generated based on 5408 records gained from herbarium specimens and literature *** life form spectra show that the majority of taxa(54.7%)belong to hemicryptophytes,followed by the tuberous,bulbous and parasitic geophytes with 45 species(17.6%)and phanerophytes with 28 taxa(10.9%).The conservation status of species according to IUCN criteria indicates that 30 taxa are Critically Endangered,52 taxa Endangered,30 taxa Vulnerable,25 taxa Near Threatened and 81 taxa are of Least *** present data were not sufficient to evaluate 38 taxa that are categorized here as Data *** new combination of Leutea translucens(=Peucedanum translucens)is validated with inclusion of Peucedanum hyrcanicum as its *** disjunct occurrence of the Caucasian species Gentiana grossheimii is reported from the eastern parts of the Hyrcanian forests in Iran for the first *** conclude that(i)the Hyrcanian forests and associated habitats in the northern slopes of the Alborz Mountains harbour tremendous floristic diversity of high conservation priority,and(ii)the Hyrcanian forest zone is an important and unique center of endemism within the Euro-Siberian region that should be considered a floristic province with a large number of relict species.

关键词： Biodiversity Distribution pattern Endemic plant Hyrcanian forests IUCN category