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Chinese Chemical Letters 2014年第4期25卷 553-556页

作者： Bagher mohammadi Mehdi Adib Department of Chemistry Payame Noor University School of Chemistry University College of ScienceUniversity of Tehran

This work described a one-pot tandem three-component synthesis of 2,4,5-triaryl-2,4-dihydro-3H- 1,2,4-triazol-3-ones using a simple reaction between phenylhydrazines, benzaldehydes and phenyl isocyanates under microwa... 详细信息

关键词： Tandem multicomponent reactions Solvent free Heterocycle Microwave Triazole

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

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 Maryam 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

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

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

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

The Multi-scale Method for Solving Nonlinear Time Space Fractional Partial Differential Equations

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 299-306页

作者： Hossein Aminikhah Mahdieh Tahmasebi Mahmoud mohammadi Roozbahani the Department of Applied Mathematics University of Guilan the Department of Applied Mathematics Faculty of Mathematical SciencesTarbiat Modares University

In this paper, we present a new algorithm to solve a kind of nonlinear time space-fractional partial differential equations on a finite domain. The method is based on B-spline wavelets approximations, some of these functions are reshaped to satisfy on boundary conditions exactly. The Adams fractional method is used to reduce the problem to a system of equations. By multiscale method this system is divided into some smaller systems which have less computations. We get an approximated solution which is more accurate on some subdomains by combining the solutions of these systems. Illustrative examples are included to demonstrate the validity and applicability of our proposed technique, also the stability of the method is discussed.

关键词： Adams fractional method B-spline wavelets multi-scale method nonlinear fractional partial differential equations

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

High-throughput phenotyping identifies plant growth differences under well-watered and drought treatments

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Journal of Integrative Agriculture 2020年第10期19卷 2429-2438页

作者： Seth TOLLEY Yang YANG Mohsen mohammadi Department of Agronomy Purdue UniversityWest LafayetteIN 47907United States College of Agricuture Department of AgronomyPurdue UniversityWest LafayetteIN 47907United States

The ability to screen larger populations with fewer replicates and non-destructive measurements is one advantage of high-throughput phenotyping(HTP)over traditinal phenotyping *** this study,two wheat accessions were grown in a controlled-environment with a moderate drought imposed from stem elongation to ***-green-blue(RGB)imaging was performed on 17 of the 22 d following the start of drought *** measurements from all plants were performed at the conclusion of the *** effect of line was signifcant for shoot dry matter,spike dry matter,root dry matter,and tller number,while the water treatment was significant on shoot dry matter and root dry *** temporal,non-destructive nature of HTP allowed the drought treatment to be significantly differentiated from the well-watered treatment after 6 d in a line from Argentina and 9 d in a line from *** difference of 3 d indicated an increased degree of drought tolerance in the line from ***,HTP from the final day of imaging accurately predicted reference plant height(r=1),shoot dry matter(r=0.95)and tller number(r=0.91).This experiment ilustrates the potential of HTP and its use in modeling plant growth and development.

关键词： high-throughput phenotyping drought controlled-environment wheat