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A complex solution on the dynamic response of sandwich graphene-reinforced aluminum-based composite beams with copper face sheets under two moving constant loads on an elastic foundation

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International Journal of Mechanical System Dynamics 2023年第3期3卷 251-264页

作者： mohammadreza Eghbali Seyed Amirhosein Hosseini Department of Mechanical Engineering University of ZanjanZanjanIran Department of Industrial Mechanical and Aerospace EngineeringBuein Zahra Technical UniversityQazvinIran

An analytical solution was used to investigate the elastic response of a sandwich beam with a graphene-reinforced aluminum-based composite(GRAC)on an elastic foundation using copper as the face layer of the functionally graded composite beam and a simply supported boundary ***'s higher-order shear deformation theory was utilized to derive the equations,which were solved in Laplace space and then converted into space–time using Laplace *** exact response of the GRAC sandwich beam was obtained by considering the displacement at the mid-span of the sandwich *** moving loads with different speed ratios were applied at a single point,and the effect of various parameters,including the spring constant,the speed ratio,the percentage of graphene,the moving load speed,and the distribution pattern,was *** study aimed to eliminate any overlap and improve the accuracy of the *** exact solving method presented has not been reported in other articles so ***,due to the difficulty of solving mathematical equations,this method is only applicable to simple boundary conditions.

关键词： GRAC beams moving load Laplace transform elastic foundation analytical solution aluminum-based

The off-site implications of deforestation on sedimentation rates and pollution in Abkenar open water (Anzali Lagoon, Caspian Sea) using radionuclide techniques and sediment quality indices

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International Journal of Sediment Research 2022年第3期37卷 370-382页

作者： mohammadreza Gharibreza Mohammad Zaman Mahmood Arabkhedri Shahriar Sobh-Zahedi Soil Conservation and Watershed Management Research Institute Agricultural Research Education and Extension Organization (AREEO) Soil and Water Management & Crop Nutrition Section Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture International Atomic Energy AgencyVienna International Centre Guilan Agricultural and Natural Resources Research and Education Center AREEO

Abkenar open water(AOW) has a 35 km~2 distribution and is the largest part of the Anzali Lagoon in the southern coastal zone of the Caspian Sea. The effects of deforestation in the upstream basin of the AOW were assessed by measuring the rate of sedimentation, sediment contamination, and ecological risk for aquatic life and end-users using radioisotopes Cesium-137 and Lead-210. The chronology of the AOW sediment column was studied using the Constant Rate of Supply model. Correlations between environmental changes and the sedimentary regime of the study area highlight the contribution of the AOW authorized international and local wood harvesting companies pre-and-post 1950 in the catchment in terms of the rate of sediment supply and the influx of toxic metals. Historical evidence shows that two specific layers formed during World Wars I and II with the mean rates of 0.185 ± 0.04(±STD) and 0.32 ± 0.02 kg/(m·y), respectively. The highest influx of alkali elements and toxic metals(nickel, cadmium, lead, zinc, and copper) into the basin occurred in 1945. Two layers of gray mud(16-50 cm) and organic-rich dark loss mud(0-16 cm) correlated well with the programmed wood harvesting *** layers accumulated from 1953 to 2000 with a mean rate of 0.6 ± 0.2 and 2 ± 0.7 kg/(m~2·y). Thus,aquatic life and end-users have been exposed to moderate to extremely high levels of toxic metals and a moderate level of contamination since the 1950 s.

关键词： Abkenar open water Accumulation rate Anzali Lagoon Sediment contamination CRS model Radioisotopes

Psychometric properties of the Persian version of the European heart failure self-care behavior scale

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Frontiers of Nursing 2022年第1期9卷 95-102页

作者： Reza Norouzadeh mohammadreza Heidari Anoshirvan Kazemnejad Department of Nursing Nursing and Midwifery FacultyShahed UniversityTehran ***Iran Department of Biostatistics Faculty of Medical SciencesTarbiat Modares UniversityTehran ***Iran

Objective:To investigate the psychometric properties of the self-care behavior scale in heart failure(HF)*** development of self-care behaviors is one of the goals of non-pharmacological care management ***:After translating the European Heart Failure Self-care Behavior scale(EHFScBS),validity was assessed through explanatory factor analysis;additionally,reliability was assessed through Cronbach alpha and *** samples comprised of 120 HF patients admitted to hospitals in Tehran during ***:The mean age of the samples was 67.3±14.04 ***-four patients(45%)were *** items of the scale had an acceptable factor *** alpha coefficient was *** intra-cluster correlation coefficient(ICC)was ***:Nurses and clinicians could benefit from the Persian version of HF self-care scale since it would enable them to rapidly assess patients’self-care behaviors and to evaluate the effectiveness of the HF management.

关键词： heart failure questionnaire reliability self-care validity

Recent progress and perspective in additive manufacturing of EMI shielding functional polymer nanocomposites

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Nano Research 2023年第1期16卷 1-17页

作者： Amirjalal Jalali Ruiyan Zhang Reza Rahmati mohammadreza Nofar Mohini Sain Chul B.Park Center for Biocomposites&Biomaterials Processing John H.Daniels Faculty of ArchitectureLandscapeand DesignUniversity of TorontoTorontoOntario M5S 3B3Canada Microcellular Plastics Manufacturing Laboratory Department of Mechanical and Industrial EngineeringUniversity of Toronto5 King's College RoadTorontoOntario M5S 3G8Canada State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Key Laboratory of Photovoltaic MaterialsSchool of Materials and New EnergyNingxia UniversityYinchuan 750021China Metallurgical&Materials Engineering Department Faculty of Chemical and Metallurgical EngineeringIstanbul Technical UniversityMaslakIstanbul 34469Turkey

Because of rapid progress in the electronics industry,the market has faced a huge demand for novel materials in the field of electromagnetic interference(EMI)*** functional polymer composites have demonstrated great potential to fulfill this *** synthesize the polymeric composites,functional conductive nanoadditives such as graphene,carbon nanotubes,and MXene are commonly added to polymeric matrices,and the conductive polymer nanocomposites exhibit promising electrical conductivity as well as EMI shielding *** manufacturing(AM),also referred to as threedimensional(3D)printing,has been increasingly employed to fabricate complicated geometry components in the medical,aerospace,and automotive *** has also been used to fabricate advanced EMI shielding materials for sensors,supercapacitors,energy storage devices,and flexible *** review aims at introducing the different 3D printing methods applied for the fabrication of EMI shielding polymer *** impact of the AM process on the functionality of the samples is also ***,the influence of the nanofiller type and amount on the microstructure and performance of the fabricated nanocomposites is ***,the prospects and recommended works for future study are outlined.

关键词： additive manufacturing electromagnetic interference(EMI)shielding functional polymer nanocomposites stretchable electronics

A combined experimental and crystal plasticity study of grain size effects in magnesium alloys

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Journal of Magnesium and Alloys 2023年第12期11卷 4445-4467页

作者： Aaditya Lakshmanan Mohsen Taheri Andani mohammadreza Yaghoobi John Allison Amit Misra Veera Sundararaghavan Department of Aerospace Engineering University of MichiganAnn ArborMI48105USA Department of Materials Science and Engineering University of MichiganAnn ArborMI48105USA Department of Mechanical Engineering University of MichiganAnn ArborMI48105USA

This work presents a method to incorporate the micro Hall-Petch equation into the crystal plasticity finite element(CPFE) framework accounting for the microstructural features to understand the coupling between grain size, texture, and loading direction in magnesium *** effect of grain size and texture is accounted for by modifying the slip resistances of individual basal and prismatic systems based on the micro Hall-Petch equation. The modification based on the micro Hall-Petch equation endows every slip system at each microstructural point with a slip system-level grain size and maximum compatibility factor, which are in turn used to modify the slip resistance. While the slip-system level grain size is a measure of the grain size, the maximum compatibility factor encodes the effect of the grain boundary on the slip system resistance modification and is computed based on the Luster-Morris factor. The model is calibrated using experimental stress-strain curves of Mg-4Al samples with three different grain sizes from which the Hall-Petch coefficients are extracted and compared with Hall-Petch coefficients predicted using original parameters from previous work. The predictability of the model is then evaluated for a Mg-4Al sample with different texture and three grain sizes subjected to loading in different directions. The calibrated parameters are then used for some parametric studies to investigate the variation of Hall-Petch slope for different degrees of simulated spread in basal texture,variation of Hall-Petch slope with loading direction relative to basal poles for a microstructure with strong basal texture, and variation of yield strength with change in grain morphology. The proposed approach to incorporate the micro Hall-Petch equation into the CPFE framework provides a foundation to quantitatively model more complicated scenarios of coupling between grain size, texture and loading direction in the plasticity of Mg alloys.

关键词： Hall-Petch Crystal plasticity Grain size Texture Magnesium alloys

Spatially engineered nonlinearity in resonant metasurfaces

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Photonics Research 2023年第2期11卷 252-259页

作者： ANNA FEDOTOVA mohammadreza YOUNESI MAXIMILIAN WEISSFLOG DENNIS ARSLAN THOMAS PERTSCH ISABELLE STAUDE FRANK SETZPFANDT Institute of Solid State Physics Friedrich Schiller University Jena07743 JenaGermany Institute of Applied Physics Abbe Center of PhotonicsFriedrich Schiller University Jena07745 JenaGermany Max Planck School of Photonics 07745 JenaGermany Fraunhofer Institute for Applied Optics and Precision Engineering 07745 JenaGermany

Spatial engineering of the nonlinear susceptibility χ^((2)) in resonant metasurfaces offers a new degree of freedom in the design of the far-field response of second-harmonic generation(SHG). We demonstrate this by applying electric field poling to lithium niobate(LN) thin films, which inverts the spontaneous polarization and thus the sign of χ^((2)). Metasurfaces fabricated in periodically poled LN films reveal the distinct influence of theχ^((2))-patterning on the spatial distribution of the second harmonic. This work is a first step toward far-field engineering of SHG in metasurfaces with electric field poling.

关键词： resonant surfaces harmonic

L-arginine alleviates postmenopausal complications in female rats by stimulating ovarian dopamine beta hydroxylase

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Asian pacific Journal of Reproduction 2022年第6期11卷 276-284页

作者： Fatemeh Lakzaei Manizheh Karami mohammadreza Jalali Nadoushan Department of Biology Faculty of Basic SciencesShahed UniversityTehranIran Department of Pathology Faculty of MedicineShahed UniversityTehranIran

Objective:To evaluate the levels of estrogen,albumin and gonadotropins(luteinizing hormone,follicle-stimulating hormone)as well as the activity of dopamine beta hydroxylase(DAβH)in aged female rats treated with nitric oxide precursor L-arginine and neuronal nitric oxide synthase antagonist ***:A total of 224 Wistar rats(36 weeks old,weighing 250 g)based on a random sampling were divided into the control and experimental groups after Pap smear *** control group received only saline(1 mL/kg)intraperitoneally(i.p.).The experiential groups were treated with L-arginine(5,25 and 50 mg/kg,i.p.)and L-NAME(5 and 25 mg/kg,i.p.)for 3 to 21 days,once a *** samples were taken from the rats and the levels of estrogen and albumin and gonadotropins in the serum were monitored by enzyme-linked immunosorbent assay kit,and the ovaries were examined immunohistopathologically for DAβH ***:L-arginine(5 mg/kg)significantly increased estrogen level(P<0.05),which was associated with DAβH activation in the ovaries.L-NAME reduced this effect when administered prior to L-arginine dose.L-arginine caused no significant change in the levels of luteinizing hormone and follicle-stimulating *** for the lowest dose of L-arginine in the shortest period,albumin levels significantly decreased in other treatments compared to the control group(P<0.05).Conclusions:L-arginine is likely to reduce postmenopausal problems due to an increased nitric oxide level.

关键词： Postmenopausal Estrogen Albumin Dopamine beta-hydroxlase L-arginine Nitric oxide

Variant selection in laser powder bed fusion of non-spherical Ti-6Al-4V powder

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Journal of Materials Science & Technology 2023年第16期147卷 56-67页

作者： mohammadreza Asherloo Ziheng Wu Julian E.C.Sabisch Iman Ghamarian Anthony D.Rollett Amir Mostafaei Department of Mechanical Materials and Aerospace EngineeringIllinois Institute of Technology10 W 32nd StreetChicagoIL 60616United States Materials Engineering Division Lawrence Livermore National Laboratory7000 East AveLivermoreCA 94550United States Samuel Roberts Noble Microscopy Laboratory University of OklahomaNormanOK 73019United States School of Aerospace and Mechanical Engineering University of OklahomaNormanOK 73019United States Department of Materials Science and Engineering Carnegie Mellon UniversityPittsburghPA 15213United States

The presence ofα/αon priorβ/βgrain boundaries directly impacts the final mechanical properties of the titanium ***β/βgrain boundary variant selection of titanium alloys has been assumed to be unlikely owing to the high cooling rates in laser powder bed fusion(L-PBF).However,we hypothesize that powder characteristics such as morphology(non-spherical)and particle size(50–120μm)could affect the initial variant selection in L-PBF processed Ti-6Al-4V alloy by locally altering the cooling *** the high cooling rate found in L-PBF,results showed the presence ofβ/βgrain boundaryαlath growth inside two adjacent priorβ*** backscatter diffraction micrographs confirmed the presence ofβ/βgrain boundary variant selection,and synchrotron X-ray high-speed imaging observation revealed the role of the“shadowing effect”on the locally decreased cooling rate because of keyhole depth reduction and the consequentβ/βgrain boundaryαlath *** self-accommodation mechanism was the main variant selection driving force,and the most abundantα/αboundary variant was type 4(63.26°//[10553¯]).The dominance of Category IIαlath clusters associated with the type 4α/αboundary variant was validated using the phenomenological theory of martensite transformations and analytical calculations,from which the stress needed for theβ→αtransformation was calculated.

关键词： Variant selection Phase formation Additive Manufacturing Hydride-dehydride powder Texture analysis Electron backscattered diffraction

Effects of bond coat and top coat(including nano zones) structures on morphology and type of formed transient stage oxides at pre-heat treated nano NiCrAlY/nano ZrO_2-8%Y_2O_3 interface during oxidation

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Journal of Rare Earths 2015年第9期33卷 983-994页

作者： mohammadreza Daroonparvar Department of Materials Engineering Faculty of Engineering Azad UniversityRoudehen Branch

Bond coat geometry is able to significantly influence thermally grown oxide （TGO） layer formation and growth in thermal barrier coating systems at the onset of oxidation. Moreover, nanostructured yttria stabilized zirconia coating with three model structure （including nano zones） could reduce oxygen partial pressure to the formation pressure of continues alumina oxide scale which was able to protect the substrate from extra oxidation and corrosion. Thus, nano NiCrA1Y/nano YSZ and normal NiCrA1Y/nano YSZ coatings were prepared by air plasma spray method and then evaluated by high temperature oxidation test at 1000℃ for 160 h. As-sprayed samples were also pre-oxidized at 1000 ℃ for 48 h and then examined by electrochemical polarization test. The corrosion rate of the pre-oxidized nano NiCrA1Y/nano YSZ coating was estimated to be the lowest compared to that of the other samples. It might be related to the formation of continues alumina layer on the nano NiCrA1Y at the onset of oxidation. This continuous layer could reduce the penetration of the aggressive solution into the NiCrA1Y coating and acted as a protective layer （with the lowest anodie current density）. This layer also lessened TGO growth rate at the stages Ⅱ and Ⅲ of the growth.

关键词： ceramics plasma deposition X-ray diffraction diffusion rare earths