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Chinese Physics B 2018年第8期27卷 280-289页

作者： Asghar mohammadi Hesari Hamid Reza Shamlouei Chemistry Department Lorestan UniversityI(horram AbadLorestanIraa

According to density functional theory, we investigate the effects of BF3, BF4, BCI3, A1F3, AICI3, A1Br3, 13eF3, GaF3, GaC13, GaBr3, NO3, BS2, BSO, BO2, F2, PFs, PC15, and ASF5 molecules on the geometric, electronic, linear, and nonlinear optical properties of an Mg12012 nanocage. The thermodynamic stability and feasibility of the adsorption process are investigated by analyzing the free energy. It is shown that the adsorptions of almost all molecules on the Mg12OI2 surface are exothermic. The calculations of the polarizability of these nanoclusters show that among the studied molecules, BeF3 has the largest influence on the polarizability value （a≈315 a.u., the unit a.u. is short for atomic unit）. The static first hyperpolarizability （β0） value is increased in the presence of these superhalogens. This increase is greatest for BeF3 and BF4 of which the highest value of the first hyperpolarizability （βO≈ 5775 a.u.） is related to a BeF3_c（e@Mgl2Ol2） nanocluster. The adsorption position is a key to estimating the value of increasing the first hyperpolarizability.

关键词： Mg1201 polarizability hyperpolarizability binding energy nanocage DFT calculation

Incorporation of 3-dimensional lycopodium with hydrophobic nature and interconnected nano-channels into polyvinylidene fluoride membranes for desalination applications by vacuum membrane distillation

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Frontiers of Chemical Science and Engineering 2023年第9期17卷 1162-1182页

作者： Saeed Seraj Toraj mohammadi ma.ya. Ahmadzadeh Tofighy Center of Excellence for Membrane Research and Technology Department of ChemicalPetroleum and Gas EngineeringIran University of Science and Technology(IUST)Tehran***Iran

In the present research,for the first time,lycopodium as a novel nanofiller was incorporated into a polyvinylidene fluoride matrix to fabricate lycopodium/polyvinylidene fluoride flat-sheet membrane for desalination applications by vacuum membrane distillation *** prepared lycopodium/polyvinylidene fluoride membranes and lycopodium were characterized by field emission scanning electron microscopy,X-ray diffraction,Fourier transform infrared,energy dispersive X-ray,and mapping *** contact angle and liquid entry pressure measurements were also *** surface methodology was applied to optimize membrane structure and *** optimized lycopodium/polyvinylidene fluoride membrane exhibits superior performance compared to the neat polyvinylidene fluoride membrane in terms of flux,salt rejection,water contact angle,and *** vacuum membrane distillation experiments,using a 15000 ppm NaCl solution as a feed at 70℃,the neat polyvinylidene fluoride membrane,optimum membrane,and agglomerated membrane(with high lycopodium loading)demonstrated 3.80,25.20,and 14.83 LMH flux and 63.30%,99.99%,99.96%salt rejection,*** improvement in flux and salt rejection of the optimized membrane was related to the presence of lycopodium with hydrophobic nature and interconnected nano-channels in membrane *** was found that lycopodium,as the most hydrophobic material,effectively influences the membrane performance and structure for membrane distillation applications.

关键词： lycopodium hoprobhobicity vucuum embrane distillation desalination

Study of Current Sheath Velocity and Its Distribution Using Tridimensional magnetic Probe in Sahand Plasma Focus

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Plasma Science and Technology 2015年第5期17卷 353-357页

作者： M.A.mohammadi S.HEDYEH Department of Atomic and Molecular Physics Faculty of PhysicsUniversity of Tabriz Research Center of Astrophysics and Applied Physics University of Tabriz

The current sheath velocity in 0.25 Torr gas pressure of Filippov type plasma focus is studied experimentally. By using two tridimensional magnetic probes on top of the anode surface, the current sheath velocity is measured for argon, oxygen and nitrogen. Additionally, the effect of charging voltage on the current sheath velocity is studied in both axial and radial phases. We found that, the maximum current sheath velocities at both radial and axial phases are respectively 4.33 ± 0.28 （cm/μs） and 3.92 ± 0.75 （cm/μs） with argon as the working gas at 17 kV. Also, the minimum values of current sheath velocity are 1.48 ± 0.15 （cm/μs） at the radial phase and 1.14 ± 0.09 （cm/μs） at the axial phase with oxygen at 12 kV. The current sheath velocity at the radial phase is higher than that at the axial phase for all gases and voltages. In this study, variation of the full width half maximum （FWHM） of magnetic probe signals with voltage is investigated for different gases at radial and axial phases.

关键词： plasma focus tridimensional magnetic probe current sheath dynamics

A Review on Plug-in Electric Vehicles:Introduction, Current Status, and Load Modeling Techniques

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 412-425页

作者： Ali Ahmadian Behnam mohammadi-Ivatloo Ali Elkamel Department of Electrical Engineering University of BonabBonabIran Institute of Research and Development Duy Tan UniversityDa Nang 550000Vietnam College of Engineering Khalifa University of Science and Technologythe Petroleum InstituteAbu DhabiUnited Arab Emirates

Plug-in electric vehicle(PEV) load modeling is very important in the operation and planning studies of modern power system nowadays. Several parameters and considerations should be taken into account in PEV load modeling, making it a complex problem that should be solved using appropriate techniques. Different techniques have been introduced for PEV load modeling and each of them has individual specifications and features. In this paper, the most popular techniques for PEV load modeling are reviewed and their capabilities are evaluated. Both deterministic and probabilistic methods are investigated and some practical and theoretical hints are presented. Moreover, the characteristics of all techniques are compared with each other and suitable methods for unique applications are proposed. Finally, some potential research areas are presented for future works.

关键词： Plug-in electric vehicles load modeling deterministic and probabilistic techniques distribution networks

Modification of rock mass rating system:Interbedding of strong and weak rock layers

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1165-1170页

作者： Mohammad mohammadi Mohammad Farouq Hossaini The Alborz Tunnel Site Geodata EngineeringMazandaran ProvinceIran Faculty of Mining Engineering Engineering University CollegeUniversity of TehranTehranIran

Rock mass classification systems are the very important part for underground projects and rock mass rating(RMR) is one of the most commonly applied classification systems in numerous civil and mining projects. The type of rock mass consisting of an interbedding of strong and weak layers poses difficulties and uncertainties for determining the RMR. For this, the present paper uses the concept of rock bolt supporting factor(RSF) for modification of RMR system to be used in such rock mass types. The proposed method also demonstrates the importance of rock bolting practice in such rock masses. The geological parameters of the Shemshak Formation of the Alborz Tunnel in Iran are used as case examples for development of the theoretical approach.

关键词： Rock mass rating(RMR) Strong and weak rock layers Interbedding Rock bolt supporting factor(RSF) Alborz tunnel

Experimental measurement and correlation of solubility of β-carotene in pure and ethanol-modified subcritical water

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2620-2625页

作者： Hadi Share mohammadi Ali Haghighi As ma.ya. Khajenoori Faculty of Chemical Petroleum and Gas EngineeringSemnan UniversitySemnan 35131-19111Iran

For the first time,the solubility ofβ-carotene in pure and ethanol-modified subcritical water(SW)using the static method was *** experimental runs were performed at a temperature ranging from 298.15 to 403.15 K and 0–10%(w/w)of ethanol as a modifier at a constant pressure of 5 *** were analyzed by UV–vis *** solubility ofβ-carotene was found to range from 1.084×10^-8 to 227.1×10^-8 mol fractions in the subcritical water in above mentioned *** obtainedβ-carotene solubility data were correlated using the linear model and modified Apelblat *** obtained results showed the modified Apelblat model was better for estimating the solubility ofβ-carotene in *** values of the rootmean-square deviation(RMSD)between experimental and correlated data were calculated and used as the index of validity and accuracy for the ***,thermodynamic properties of the solution such as the Gibbs free energy of solution,enthalpy,and entropy of solution were estimated.

关键词： Subcritical water β-Carotene Solubility Semi-empirical model

Gastrointestinal viral shedding in children with SARS‑CoV‑2:a systematic review and meta‑analysis

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World Journal of Pediatrics 2022年第9期18卷 582-588页

作者： Sepideh Benvari Shima mahmoudi Mohsen mohammadi Department of Microbiology Faculty of MedicineQazvin University of Medical SciencesQazvinIran Pediatric Infectious Disease Research Center Tehran University of Medical SciencesTehranIran Non-Communicable Pediatric Diseases Research Center Health Research InstituteBabol University of Medical SciencesBabolIran

Background Coronavirus disease 2019(COVID-19)has diferent manifestations in pediatric *** is assumed that they might present more gastrointestinal symptoms with a diferent viral shedding pattern in gastrointestinal *** this systematic review and meta-analysis,we aimed to evaluate the viral shedding pattern in gastrointestinal specimens of children with *** We searched all published studies in English language in PubMed,Web of Science,and Scopus,up to date as of October *** search included the term"severe acute respiratory syndrome coronavirus 2,COVID-19,SARS-CoV-2,novel coronavirus,or coronavirus;and shed,excrete,secret,or carriage;and stool or rectal;and children or pediatrics".We included studies evaluating SARS-CoV-2 shedding in gastrointestinal specimens,including rectal swabs and stool samples of children with COVID-19 *** excluded duplicated data,case reports,and studies without original *** Twelve studies met the eligibility criteria for the qualitative synthesis,10 of which were included in the *** pooled prevalence of gastrointestinal severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)RNA in children with COVID-19 was 86%(95%confdence interval 73%–96%,I 2=62.28%).After respiratory specimen had become negative,72%(43/60)had persistent shedding in gastrointestinal *** gastrointestinal RNA had a positive test result for more than 70 days after symptoms *** Gastrointestinal shedding of SARS-CoV-2 might occur in a substantial portion of children and might persist long after negative respiratory *** research is recommended to fnd the role of SARS-CoV-2 gastrointestinal shedding in transmission in children.

关键词： Coronavirus disease 2019(COVID-19) Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Viral shedding

Sol-gel derived nanocrystalline and mesoporous barium strontium titanate prepared at room temperature

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Particuology 2011年第3期9卷 235-242页

作者： Mohammad Reza mohammadi Derek J.Fray Department of materials Science & Engineering Sharif University of Technology Department of materials Science & Metallurgy University of Cambridge

Perovskite-type barium strontium titanate （BST） thin films and powders with nanocrystalline and mesoporous structure were prepared by a straightforward particulate sol-gel route at room temperature. The prepared sol had a narrow particle size distribution of about 20 nm. X-ray diffraction （XRD） revealed that phase composition and preferable orientation growth of BST depended upon the annealing temperature. Transmission electron microscope （TEM） images showed that the crystallite size of the powders decreased with increasing annealing temperature from 8 nm at 25 ℃ down to 5 nm at 800 ℃. Field emission scanning electron microscope （FE-SEM） analysis and atomic force microscope （AFM） images revealed that BST thin films had mesoporous and nanocrystafiine structure with average grain size of 3Onm at 600 ℃. Based on Brunauer-Emmett-Teller （BET） analysis, the synthesized BST showed mesoporous structure containing nnres with needle, and nlate shanes and BET surface area in the range of 49-32 m^2/g at 500-800℃

关键词： Barium strontium titanate Room temperature Sol-gel chemistry Nanostructure

A STRONG CONVERGENCE THEOREM FOR QUASI-EQUILIBRIUM PROBLEMS IN BANACH SPACES

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Acta mathematica Scientia 2022年第1期42卷 221-232页

作者： Mehdi mohammadi G.Zamani ESKANDANI Department of mathematics Payame Noor UniversityTehranIran Department of Pure mathematics Faculty of Mathematical SciencesUniversity of TabrizTabrizIran

In this paper,we study an extragradient algorithm for approximating solutions of quasi-equilibrium problems in Banach *** prove strong convergence of the sequence generated by the extragradient method to a solution of... 详细信息

关键词： demiclosed,extragradient algorithm quasi-equilibrium problem quasiΦ-nonexpansive mapping strong convergence

Synthesis of a PEBAX-1074/ZnO nanocomposite membrane with improved CO_2 separation performance

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Journal of Energy Chemistry 2017年第3期26卷 454-465页

作者： Navid Azizi Toraj mohammadi Reza Mosayebi Behbahani Research and Technology Center of Membrane Processes Chemical Engineering DepartmentIran University of Science and Technology (IUST) Gas Engineering Department Petroleum University of Technology

In this investigation, polymeric nanocomposite membranes（PNMs） were prepared via incorporating zinc oxide（ZnO） into poly（ether-block-amide）(PEBAX-1074) polymer matrix with different loadings. The neat membrane and nanocomposite membranes were prepared via solution casting and solution blending methods, respectively. The fabricated membranes were characterized by field emission scanning electron microscopy（FESEM） to survey cross-sectional morphologies and thermal gravimetric analysis（TGA）to study thermal stability. Fourier transform infrared（FT-IR） and X-ray diffraction（XRD） analyses were also employed to identify variations of the chemical bonds and crystal structure of the membranes, respectively. Permeation of pure gases, CO, CHand Nthrough the prepared neat and nanocomposite membranes was studied at pressures of 3–18 bar and temperature of 25 °C. The obtained results showed that the fabricated nanocomposite membranes exhibit better separation performance compared to the neat PEBAX membrane in terms of both permeability and selectivity. As an example, at temperature of 25 °C and pressure of 3 bar, COpermeability, ideal CO/CHand CO/Nselectivity values for the neat PEBAX membrane are 110.67 Barrer, 11.09 and 50.08, respectively, while those values are 152.27 Barrer,13.52 and 62.15 for PEBAX/ZnO nanocomposite membrane containing 8 wt% ZnO.

关键词： Nanocomposite membrane ZnO nanoparticles PEBAX-1074 CO2/CH4 separation