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Numerical study on polymer nanofibers with electrically charged jet of viscoelastic fluid in electrospinning process

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journal of Central South University 2017年第10期24卷 2275-2280页

作者： P.Valipour h.Zaersabet m.hatami ali Zolfagharian S.E.Ghasemi Department of Textile and Apparel Qaemshahr BranchIslamic Azad UniversityQaemshahrIran Department of mechanical Engineering Esfarayen University of TechnologyEsfarayenNorth KhorasanIran School of Engineering Deakin UniversityGeelongVictoria 3216Australia Young Researchers and Elite Club Sari BranchIslamic Azad UniversitySariIran

Electrospinning is a useful and efficient technique to produce polymeric nanofibers. Nanofibers of polymers are electrospun by creating an electrically charged jet of polymer solution. Numerical study on non-Newtonian and viscoelastic jets of polymer nanofibers in electrospinning process is presented in this work. In particular, the effect of non-Newtonian rheology on the jet profile during the electrospinning process is examined. The governing equations of the problem are solved numerically using the Keller-Box method. The effects of yield stress and power-law index on the elongation, velocity, stress and total force are presented and discussed in detail. The results show that by increasing the values of yield stress, the fluid elongation is reduced significantly.

关键词： nanofibers electrospinning electrically charged jet viscoelastic fluid synthetic polymers

Ion population fraction calculations using improved screened hydrogenic model with l-splitting

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Chinese Physics B 2018年第10期27卷 424-432页

作者： Amjad ali G Shabbir Naz Rukhsana Kouser Ghazala Tasneem m Saleem Shahzad Aman-ur-Rehman m h Nasim Department of Physics and Applied mathematics Pakistan Institute of Engineeringand Applied Sciences Department of Nuclear Engineering Pakistan Institute of Engineeringand Applied Sciences

Ion population fraction（IPF） calculations are very important to understand the radiative spectrum emitted from the hot dense matter. IPF calculations require detailed knowledge of all the ions and correlation interactions between the electrons of an ion which are present in a plasma environment. The average atom models, e.g., screened hydrogenic model with l-splitting（ShmL）, now have the capabilities for such calculations and are becoming more popular for in line plasma calculations. In our previous work [ali A, Shabbir Naz G, Shahzad m S, Kouser R, Rehman A and Nasim m h 2018 high Energy Density Phys. 26 48], we have improved the continuum lowering model and included the exchange and correlation effects in ShmL. This study presents the calculation of IPF using classical theory of fluctuation for our improved screened hydrogenic model with l-splitting（I-ShmL） under local thermodynamic equilibrium conditions for iron and aluminum plasma over a wide range of densities and temperatures. We have compared our results with other models and have found a very good agreement among them.

关键词： self-consistent average atom model average ionization state ion population

Circular neighbor-balanced designs using cyclic shifts

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Science China mathematics 2009年第10期52卷 2243-2256页

作者： IQBAL Ijaz TAhIR m. h. GhAZali Syed Shakir ali Department of Statistics Bahauddin Zakariya University Department of Statistics The Islamia University of Bahawalpur

In agriculture experiments, the response on a given plot may be affected by the treatments on neighboring plots as well as by the treatments applied to that plot. In this paper we consider such type of situations and construct circular neighbor-balanced designs (CNBDs) by the method of cyclic shifts or sets of shifts. An important feature of this method is that the properties of a design can be easily obtained from the sets of shifts instead of constructing the actual blocks of the design. That is, the off-diagonal elements of the concurrence matrix can be easily obtained from the sets of shifts. Since the suggested designs are circular, balanced and binary, so they are universally optimal.

关键词： A-optimal circular designs cyclic shifts treatment-balanced designs universally optimal 05B05 62K05 62K10

Effect of Pyrrole and N-methylpyrrole Coatings on Corrosion Resistance of mild Steel

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材料热处理学报 2004年第05B期25卷 1137-1141页

作者： ali Ashrafi m.A.Golozar S.mallakpour ali Ghasemi Department of materials Engineering Isfahan University of Technology Isfahan 84154 Iran Organic Polymer Chemistry Research Laboratory College of Chemistry Isfahan University of Technology Isfahan 84156 Iran

Electrochemical polymerizations of various ratios of pyrrole and methylpyrrole monomers were performed in aqueous toluene-4-sulfinic acid sodium salt (T4SNa) electrolyte, using galvanostatic method. ph of electrolyte was adjusted by p-toluene sulfonic acid (PTSA). In order to prevent corrosion of mild steel substrates during coating deposition, specimens were pretreated in 0.5m oxalic acid solution, employing galvanostatic method. This would passivate the steel substrate and facilitate the coating process as well. Corrosion resistance of coated substrates was investigated in 1m NaCl solution using Tafel polarization technique. In addition, using scanning electron microscopy (SEm), morphological characterization of coatings produced, was investigated. Regarding the corrosion characteristics, results obtained revealed that the ratio of 1 to 1 (Pyrrole/methylpyrrole) could play an important role.

关键词：导电聚合物电引发聚合吡咯耐蚀性低碳钢

Parameters for Cold Collisions of Lithium and Caesium Atoms

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Chinese Physics Letters 2011年第6期28卷 56-58页

作者： jamieson m.j Ouerdane h School of Computing Science University of GlasgowGlasgow G128QQUK mediterranean Institute of Fundamental Physics Via Appia Nuova 3100040 MarinoRomeItaly CNRT matériaux UmS CNRS 3318 6 Boulevard Maréchal Juin14050 Caen CedexFrance

We calculate the s-wave scattering length and effective range and the p-wave scattering volume for 7Li atoms interacting with 133Cs atoms via the X1Σ+molecular *** length and volume are found by fitting the log-derivative of the zero energy wave function evaluated at short range to a long range expression that accounts for the leading van der Waals dispersion potential and then incorporating the remaining long range dispersion contributions to first *** effective range is evaluated from a quadrature *** calculated parameters are checked from the zero energy limits of the scattering phase *** comment on ill-conditioning in the calculated s-wave scattering length.

关键词： potential dispersion checked

Fractional Analysis of Dynamical Novel COVID-19 by Semi-Analytical Technique

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Computer modeling in Engineering & Sciences 2021年第11期129卷 705-727页

作者： S.Iqbal D.Baleanu javaid ali h.m.Younas m.B.Riaz School of Systems and Technology University of Management and TechnologyLahore54770Pakistan Department of mathematics Cankaya UniversityAnkara06530Turkey Institute of Space Sciences MagureleBucharest077125Romania Department of mathematics Govt.College TownshipPunjab Higher Education DepartmentLahore54770Pakistan Department of mathematics Islamia University of BahawalpurBahawalpur63100Pakistan Department of mathematics University of Management and TechnologyLahore54770Pakistan Institute for Groundwater Studies University of the Free StateBloemfontein9300South Africa

This study employs a semi-analytical approach,called Optimal homotopy Asymptotic method(OhAm),to analyze a coronavirus(COVID-19)transmission model of fractional *** proposed method employs Caputo’s fractional derivatives and Reimann-Liouville fractional integral sense to solve the underlying *** the best of our knowledge,this work presents the first application of an optimal homotopy asymptotic scheme for better estimation of the future dynamics of the COVID-19 *** proposed fractional-order scheme for the parameterized model is based on the available number of infected cases from january 21 to january 28,2020,in Wuhan City of *** the considered real-time data,the basic reproduction number is R0≈2.48293 that is quite *** proposed fractional-order scheme for solving the COVID-19 fractional-order model possesses some salient features like producing closed-form semi-analytical solutions,fast convergence and non-dependence on the discretization of the *** graphical presentations have demonstrated the dynamical behaviors of subpopulations involved in the underlying fractional COVID-19 *** successful application of the scheme presented in this work reveals new horizons of its application to several other fractional-order epidemiological models.

关键词： Novel COVID-19 semi-analytical scheme fractional analysis

New Bi-metallic Single Source Precursors for the Deposition of Thin Films of Semiconductor Ceramics

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journal of materials Science & Technology 2007年第2期23卷 196-200页

作者： U.Salma m.mazhar j.I.Akhter Z.ali Department of Chemistry Quaid-i-Azam UniversityIslamabad 45320Pakistan Physics Division Pakistan Institute of Nuclear Science and TechnologyP.O.NiloreIslamabadPakistan

Stable binary single source precursors （SSP） for the deposition of thin films of ceramic semiconductors of composition SnO·GeO were synthesized by close circuit chemical vapour deposition （CCCVD） method. Elemental analysis and spectroscopic techniques were used to characterize the precursors. Scanning electron microscopy （SEm） and energy dispersive spectroscopy （EDS） were employed to characterize the thin films. Resistivity measurements were conducted to show that the films are of semiconducting nature.

关键词： Single source precursors CCCVD Organotin carboxylates

Effect of the Geometrical Parameter of Openmicrochannel on Pool Boiling Enhancement

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Frontiers in heat and mass Transfer 2024年第5期22卷 1421-1442页

作者： ali m.h.Al-Obaidy Ekhlas m.Fayyadh Amer m.Al-Dabagh mechanical Engineering Department University of Technology-IraqBaghdad10066Iraq

high heat dissipation is required for miniaturization and increasing the power of electronic *** boiling is a promising option for achieving efficient heat dissipation at low wall superheat without the need for moving *** studies have focused on improving heat transfer efficiency during boiling by modifying the surface of the heating *** paper presents an experimental investigation on improving pool boiling heat transfer using an open *** primary goal of this work is to investigate the impact of the channel geometry characteristics on boiling heat ***,rectangular microchannels were prepared on a circular copper test piece with a diameter of 20 ***,the boiling characteristics of these microchannels were compared with those of a smooth surface under saturated conditions using deionized *** this investigation,a wire-cutting electrical discharge machine(EDm)machine was used to produce parallel microchannels with channel widths of 0.2,0.4,and 0.8 *** fin thicknesses were 0.2,0.4,and 0.6 mm,while the channel depth remained constant at 0.4 *** results manifested that the surface featuring narrower fins and broader channels achieved superior *** heat transfer coefficient(hTC)was enhanced by a maximum of 248%,and the critical heat flux(ChF)was enhanced by a maximum of 101%compared to a plain ***,the obtained results were compared with previous research and elucidated a good agreement.

关键词： Pool boiling microchannel surface geometrical parameter heat transfer enhancement critical heat flux

Improving electrical,optical and radiation shielding properties of polyvinyl alcohol yttrium oxide composites

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journal of Rare Earths 2023年第12期41卷 2002-2009,I0007页

作者： Shams A.m.Issa D.E.Abulyazied Albandari W.Alrowaily h.A.Saudi E.S.ali A.m.A.henaish hesham m.h.Zakaly Department of Physics Faculty of ScienceUniversity of TabukTabukSaudi Arabia Faculty of Science Al-Azhar UniversityAssiut BranchAssiut71524Egypt Polymer Lab Department of PetrochemicalEgyptian Petroleum Research InstituteNasr CityCairoEgypt Department of Physics College of SciencePrincess Nourah Bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Physics Department Faculty of ScienceAl-Azhar University(Girls Branch)Nasr CityCairoEgypt Institute of Physics and Technology Ural Federal UniversityYekaterinburg620002Russia Physics Department Faculty of ScienceTanta UniversityTanta31527Egypt Istinye University Faculty of Engineering and Natural SciencesComputer Engineering DepartmentIstanbul34396Turkey

This research aims to study the impact of yttrium oxide on the radiation protection features of polyvinyl alcohol(PVA) for gamma shielding *** yttrium oxide(Y_(2)O_(3)) was instilled through the PVA matrix by different contents(x=0.1 wt%,0,3 wt%,0,7 wt%,0,9 wt%),The morphology of the prepared PVA/Y_(2)O_(3)composites was characterized using scanning electron microscopy(SEm).The samples were investigated using absorption edge,transmittance spectra and dielectric *** transmittance and the bandgap energy decrease as the Y2O3content increases while there is an increase in ε’ and ε" as well as the ac conductivity with the content increment of Y_(2)O_(3)till 0.7 wt%.The te mperature dependence of the dc conductivity was measured for all samples in the range of 260-460 K,and it increases with the temperature *** correlate the electrical characteristics of the PVA/Y_(2)O_(3)composites with their structure and evaluate electrical properties with the help of equivalent circuit matching with the experimentally electrical response in the impedance spectrum,the radiation protection properties were also investigated to get the radiation shielding performance of these PVA/Y_(2)O_(3)composite films with varying Y_(2)O(3)*** linear attenuation coefficient(μ),half value layer(T_(0.5)),and mass attenuation coefficient(μm) were *** to all obtained data,PVA/Y_(2)O_(3)composite films with various percentages(0.1 wt%,0.3 wt%,0.7 wt%,0.9 wt%) can be used as a radiation shielding material.

关键词： Yttriumoxide/PVA Electrical properties Optical properties Gamma shielding Rare earths