Sharif University of TechnologyScientia Iranica1026-309828320210601An integrated model for predicting the size of silver nanoparticles in montmorillonite/chitosan bionanocomposites: A hybrid of data envelopment analysis and genetic programming approach187118832204110.24200/sci.2020.52510.2748ENE.SarvestaniDepartment of Materials Science and Engineering, Shahid Bahonar University of Kerman, Kerman, P.O. Box 76135-133, IranG. R.KhayatiDepartment of Materials Science and Engineering, Shahid Bahonar University of Kerman, Kerman, P.O. Box 76135-133, Iran0000-0001-7387-5252Journal Article20181220Unique chemical and physical properties of silver nanoparticles (AgNPs) enhances its usages in various categories such as medical utilities. Due to the high dependency of AgNPs properties to the size, this study is an attempt to employ gene expression programing (GEP) for constructing a quantitative model for estimating the size of AgNPs in montmorillonite/chitosan bionanocomposites that prepared by chemical approach. Generalization capabilities, fault tolerance, noise tolerance, high parallelism, nonlinearity and significant information processing characteristics are the main advantages of GEP. Accordingly, the practical parameters including reaction temperature, AgNO3 concentration, weight of montmorillonite in aqueous AgNO3/chitosan solution (WMMT) and the percentage of chitosan are selected as input parameters through GEP modeling. The accuracy of proposed models are investigated by statistical indicators including mean absolute percentage error (MAPE), root relative squared error (RRSE), root mean square error (RMSE) and correlation coefficient (R2). Finally, the best model is selected by R2 = 0.987, RMSE = 0.100, RRSE = 0.146 and MAPE = 0.221. The sensitivity analysis confirmed that the percentage of chitosan, concentration of AgNO3, WMMT and reaction temperature are the most effecting parameters on the size of AgNPs, respectively.https://scientiairanica.sharif.edu/article_22041_e936cd0726594710711f6be2a3fc1ddf.pdfSharif University of TechnologyScientia Iranica1026-309828320210601Design and synthesis of carbon nanotubes for adsorption utilities: An approach to direct preparation by mechanical milling at room temperature188418952200310.24200/sci.2020.52977.2979ENM.H.Khazaei FeizabadDepartment of Nano Technology, Mineral Industries Research Center (MIRC), Shahid Bahonar University of Kerman,
7618868366 Kerman, IranG. R.KhayatiDepartment of Material Science and Engineering, Shahid Bahonar University of Kerman, 7618868366 Kerman, Iran0000-0001-7387-5252S.PouresterabadiDepartment of Nano Technology, Mineral Industries Research Center (MIRC), Shahid Bahonar University of Kerman,
7618868366 Kerman, IranJournal Article20190218The carbon nanotubes (CNTs) were produced by mechanical milling of Hexane in the presence of two different catalysts (amorphous and crystalline Fe) at Ar atmosphere. Raman spectroscopy, Fourier-transform infrared spectroscopy, transmission electron microscopy, high-resolution scanning electron microscopy, Brunauer–Emmett–Teller (BET) and thermal analysis were employed to characterize the CNTs. The results showed that the amorphous catalyst induced more structural defects in CNTs respect to the crystalline catalyst. The ratio of single wall to multiwall CNTs of prepared samples were about 0.31 and 7.3 for crystalline and amorphous catalyst, respectively. Moreover, the BET results confirmed the higher adsorption capacity of the sample prepared by amorphous catalyst due to their higher structural defects.https://scientiairanica.sharif.edu/article_22003_c68f08960290bb2c218f8fd0c097ce8f.pdfSharif University of TechnologyScientia Iranica1026-309828320210601Bioconvection phenomenon for the boundary layer flow of magnetohydrodynamic Carreau liquid over a heated disk189619072227810.24200/sci.2021.53970.3518ENM.SohailDepartment of Applied Mathematics & Statistics, Institute of Space Technology Islamabad, P.O. Box 2750, Pakistan0000-0002-1490-0339U.NazirDepartment of Applied Mathematics & Statistics, Institute of Space Technology Islamabad, P.O. Box 2750, PakistanY.-M.Chu- Department of Mathematics, Huzhou University, Huzhou 313000, P. R. China.
- Hunan Provincial Key Laboratory of Mathematical Modeling and Analysis in Engineering, Changsha University of Science &
Technology, Changsha 410114, P. R. China0000-0002-0944-2134W.Al-KouzDepartment of Mechanical Engineering, College of Engineering, Prince Muhammad bin Fahd University, Al-Khobar, Saudi ArabiaP.ThounthongRenewable Energy Research Centre, Department of Teacher Training in Electrical Engineering, Faculty of Technical Education,
King Mongkut's University of Technology North Bangkok, 1518 Pracharat 1 Road, Bangsue, Bangkok 10800, ThailandJournal Article20190708A numerical examination is conducted for the magnetohydrodynamics steady Carreau fluid flow on the transport of thermal energy and mass specie comprising nanoparticles with gyrotactic microorganisms through heated disk. The role of thermophoresis and Brownian motion are added in this flow problem. Governing equations are achieved by using the boundary layer theory in view of a coupled system of PDEs involving boundary conditions. The highly non-linear system of ODEs is generated using the concept of the transformation approach. Since the system of transformed equations is highly nonlinear, so, an approximate solution is estimated via optimal homotopy method. The role of prominent parameters on velocity, thermal energy, mass specie and motile density microorganisms examined graphically. Additionally, graphical observations regarding mass specie, thermal energy and velocities are discussed briefly. It has estimated that the motion of fluid particles is diminished because of the intensity of the magnetic field while mass specie and fluid temperature rise versus enhancement the values of the magnetic field.https://scientiairanica.sharif.edu/article_22278_01600ecc17d3094eb9669cd6a4feb8a8.pdfSharif University of TechnologyScientia Iranica1026-309828320210601Preparation and investigation of optical properties and photocatalytic activity of SnO2/GO thin films190819162234210.24200/sci.2021.54336.3706ENA.H.A. JalaukhanCollege of Education for Pure Sciences, University of Kerbala, IraqB.Ghanbari ShohanyBorhan Nano Scale Company, Mashhad, IranR.EtefaghBorhan Nano Scale Company, Mashhad, IranJournal Article20190829In this paper, SnO2-pure and SnO2/GO thin films with different concentrations of graphene oxide (0, 1, 2, 3 and 4 g/ml) were synthesized using spin coating method. The synthesized thin films were used to study the structural, morphology, chemical, optical and photocatalytic degradation of Methyl Orange (MO) under UV light irradiation by X-ray diffraction (XRD) spectroscopy, field emission scanning electron microscopy (FESEM), Raman spectroscopy, Ultraviolet–visible spectroscopy and UV light respectively. The XRD results of graphene oxide show that the peak is very sharp with high intensity, which indicates a very good crystallinity of the GO structure. The band gape value of SnO2/GO thin films increase by increasing of GO concentration. Under UV light irradiation, the photocatalytic activity of synthesized samples was measured using Methyl Orange dye. The obtained results indicate that by adding graphene oxide concentration, the photocatalytic activity of the tin oxide thin film increases.https://scientiairanica.sharif.edu/article_22342_c6f46d45bc02173543156c552764c939.pdfSharif University of TechnologyScientia Iranica1026-309828320210601Entropy generation optimization and activation energy in flow of Walters-B nanomaterial191719252206310.24200/sci.2020.54593.3822ENS.JabeenDepartment of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, PakistanT.Hayat- Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000, Pakistan.
- Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi ArabiaA.AlsaediDepartment of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589, Saudi ArabiaJournal Article20191007In present research, we concentrated on the characterization of Walters-B nanofluid flow to investigate the irreversibility mechanism. Energy equation incorporated with radiation effects and heat generation phenomena. Influence of activation energy is discussed using modified Arrhenius energy term along binary chemical reaction. The consequences of thermophoresis, Brownian motion and viscous dissipation on fluids velocity, temperature of fluid particles and concentration of involved chemical species. Set of ordinary differential equations are obtained by implementing appropriate similarity variables. Governing mathematical model is solved using homotopy analysis method. Flow behavior is analyzed through Nusselt number, coefficient of drag force and mass transfer rate.https://scientiairanica.sharif.edu/article_22063_e7c26e48b7ee853cbf5e49de5d800745.pdfSharif University of TechnologyScientia Iranica1026-309828320210601Study of thermally developed flow of viscous fluid over a porous stretching surface contacting gyrotatic microorganisms using buongiorno model192619382229110.24200/sci.2021.55209.4178ENSh.Akhter- Department of Mathematics, COMSATS University Islamabad, Sahiwal 57000, Pakistan.
- Centre for Advanced Studies in Pure and Applied Mathematics (CASPAM), Bahauddin Zakariya University, Multan 60000,
Pakistan.M.AshrafCentre for Advanced Studies in Pure and Applied Mathematics (CASPAM), Bahauddin Zakariya University, Multan 60000,
PakistanJournal Article20200129Recent trend in advanced nanotechnology has developed the thermal consequences of nanoparticles due to increasing significance in various engineering and thermal extrusion systems. In this continuation, two-dimensional flow of viscous nanoliquid in the presence of gyrotactic micro-organisms encountered by a porous stretched surface is addressed numerically. The novel aspects of Brownian diffusion and thermophoresis are studied by using Buongiorno model. The thermal radiation impact is imposed in the energy equation. A set of pertinent transformations has been suggested to transform the governing non-linear partial differential equations into system of non-linear ordinary differential equations. A famous numerical method, finite difference technique, is engaged to acquire the numerical solution of modeled dimensionless equations. The flow analysis for effects of numerous prominent parameters on velocity, temperature, concentration and motile micro-organisms profiles is presented graphically. In the presence of thermal radiation, velocity profiles detract with augment of bioconvection Rayleigh number and buoyancy ratio parameter, while opposite trend is observed for boosting the Grashoff number. The porous medium as well as the radiation enhance the fluid temperature.https://scientiairanica.sharif.edu/article_22291_49b883aea3d660efd403c6cb12af1e4c.pdfSharif University of TechnologyScientia Iranica1026-309828320210601The study of the morphology and structural, optical, and J-V characterizations of (CH3NH3PbI3) perovskite photovoltaic cells in ambient atmosphere193919522226910.24200/sci.2021.55718.4372ENO.MalekanSchool of Physics, Damghan University, Damghan, IranM. M.Bagheri MohagheghiSchool of Physics, Damghan University, Damghan, IranM.AdelifardSchool of Physics, Damghan University, Damghan, IranJournal Article20200330In this paper, the synthesis processes of perovskite active films of CH3NH3PbI3 (MAPbI3) have been studied for perovskite hybrid solar cells by spin and dip coating in ambient atmosphere, and without glove box to reduce production cost for technological applications. The morphology and structural, electrical and optical properties of perovskite films have been investigated by X-ray Diffraction (XRD), Field-Emission Scanning Electron Microscopes (FE-SEM), Atomic Force Microscopes (AFM) and Ultraviolet–visible spectroscopy (UV-Vis). A precursor solution of lead Iodide (PbI2) with Dimethylformamide (DMF) solvent by spin coating at two stages (a) R=4500 rpm and (b) R=6000 rpm, and methyl ammonium iodide (CH3NH3I) with isopropanol solvent by dip coating, have been prepared for active perovskite layer (CH3NH3PbI3).https://scientiairanica.sharif.edu/article_22269_ff123d85a4be88e6892cc57e1e73d77f.pdfSharif University of TechnologyScientia Iranica1026-309828320210601The effect of silica/zeolite-A nanocomposite on the polyvinyl acetate wood adhesive195319612213910.24200/sci.2021.54076.3577ENA.OladPolymer Composite Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz,
IranM.AnarchiPolymer Composite Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz,
IranR.NosratiPolymer Composite Research Laboratory, Department of Applied Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz,
IranJournal Article20190724The silica/zeolite-A nanocomposite additive was loaded at different values (1 - 4% wt) into polyvinyl acetate matrix to improve its wood adhesive properties. The silica nanoparticles were prepared by calcination method using rice husk as source material. X-ray diffraction analysis, FTIR spectroscopy, and SEM techniques were used for the characterization of the nanocomposite. The thermal stability and adhesion properties of modified polyvinyl acetate were evaluated by thermogravimetric analysis (TGA) method and measuring the shear strength of wood joints respectively. According to the results, the addition of silica/zeolite-A nanocomposite into polyvinyl acetate in dry condition and elevated temperatures was led to the enhanced shear strength of wood joints. However, in wet conditions, improvement of shear strength which was obtained by the addition of silica/zeolite-A nanocomposite was lower than that of the dry condition. Additionally, the thermal stability of polyvinyl acetate was affected by silica/zeolite-A nanocomposite. Polyvinyl acetate containing silica/zeolite-A nanocomposite additive showed better stability in water with respect to the pristine polyvinyl acetate.https://scientiairanica.sharif.edu/article_22139_d947c9ca81cef801cd8cd633c0e9b483.pdf