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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

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

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

Biogenic amino acid methionine-based corrosion inhibitors of mild steel in acidic media

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International Journal of minerals,metallurgy and materials 2019年第4期26卷 467-482页

作者： L.K.m.O.Goni m.A.Jafar mazumder S.A.ali m.K.Nazal h.A.Al-muallem Chemistry Department King Fahd University of Petroleum and Minerals

N,N-Diallyl methionine ethyl ester hydrochloride 5 underwent alternating copolymerization with SO_2 via the Butler cyclopolymerization protocol in dimethyl sulfoxide(DmSO) to give water-soluble cycloterpolymer 6 with a ～1:1 molar ratio of sulfide and sulfoxide groups as a result of oxygen transfer from DmSO. half of the sulfide groups in 6, upon oxidation with h_2O_2, afforded polymer sulfoxide 7 and polymer sulfone 8. The solution properties of these polymers were determined via a viscometric technique. The thermal stability of these polymers was determined by thermogravimetric analysis. The inhibition efficiency obtained from gravimetric mass loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques agreed well with each other. The corrosion efficiencies increase with increasing concentration of the polymers. At a polymer concentration of 175 mm, the maximum inhibition efficiency of copolymer compounds 6–8 was determined to be 92%, 97%, and 95%, respectively. The synthesized polymer compounds acted as mixed-type inhibitors. Polymer compound 7 adsorbed onto the metal surface via chemisorption and physisorption and obeyed Langmuir, Temkin, and Freundlich adsorption isotherms. Analyses by X-ray photoelectron spectroscopy and scanning electron microscopy–energy-dispersive X-ray spectroscopy indicated that the adsorbed polymers formed a thin film on the metal surface and prevented further corrosive attack.

关键词： cyclopolymerization methionine methionine sulfoxide methionine sulfone diallylamine salt corrosion inhibition

Comparisons of the suture zones along a geotraverse from the Scythian Platform to the Arabian Platform

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Geoscience Frontiers 2014年第6期5卷 855-875页

作者： ali Yilmaz Shota Adamia hüseyin Yilmaz Cumhuriyet University Engineering FacultyDepartment of Environmental EngineeringKayseri StreetCU.CampusTR-58140 SivasTurkey Nodia Institute of Geophysics 1M.Alexidze Str.0195TbilisiGeorgia Cumhuriyet University Engineering FacultyDepartment of Geophysical EngineeringTR-58140 SivasTurkey

The area from the Greater Caucasus to the southeast Turkey is characteri：;.ed and shaped by several major continental blocks. These are Scythian Platform, Pontian-Transcaucasu.,; Continent-Arc System （PTCAS）, the Anatolian-lranian and the Arabian Platforms. The aim of this paper is to define these continental blocks and describe and also compare their boundary relationships along the suture zones. The Scythian Platform displays the evidence of the hercynian and Alpine orogens. This platform is separated from the PTCAS by the Greater Caucasus Suture Zone. The incipient collision began along this suture zone before middle-late Carboniferous whereas the final collision occurred before Oligocene. The PTCAS can be divided into four structural units：（1） the Georgian Block - northern part of the Pontian-Transcaucasian island-arc, （2） the southern and eastern Black Sea Coast-Adjara-Trialeti Unit, （3） the Artvin-Bolnisi Unit, comprising the northern part of the southern Transcaucasus, and （4） the Imbricated Bayburt-Garabagh Unit. The PTCAS could be separated from the Anatolian Iranian Platform by the North Anatolian-Lesser Caucasus Suture （NALCS） zone. The initial collision was developed in this suture zone during Senonian-early Eocene and final collision before middle Eocene or Oligocene-miocene. The Anatolian-lranian Platform （AIP） is made up of the Tauride Platform and its metamorphic equivalents together with Iranian Platform. It could be separated from the Arabian Platform by the Southeastern Anatolian Suture （SEAS） zone. The collision ended before late miocene along this suture zone. The southernmost continental block of the geotraverse is the Arabian Platform, which constitutes the northern part of the Arabian-African Plate. This platform includes a sequence from the Precambrian felsic volcanic and clastic rocks to the Campanian-early maastrichtian fiyschoidal clastics. All the suture zones include mORB and SSZ-types ophiolites in different ages. however, the ages of

关键词： Scythian Plattorm Arabian Platform Suture zones Ceotraverse

Augmented Lyapunov approach to h_∞ state estimation of static neural networks with discrete and distributed time-varying delays

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Chinese Physics B 2015年第5期24卷 140-147页

作者： m.Syed ali R.Saravanakumar Department of mathematics Thiruvalluvar University

This paper deals with h∞ state estimation problem of neural networks with discrete and distributed time-varying delays. A novel delay-dependent concept of h∞ state estimation is proposed to estimate the h∞ performance and global asymptotic stability of the concerned neural networks. By constructing the Lyapunov-Krasovskii functional and using the linear matrix inequality technique, sufficient conditions for delay-dependent h∞ performances are obtained, which can be easily solved by some standard numerical algorithms. Finally, numerical examples are given to illustrate the usefulness and effectiveness of the proposed theoretical results.

关键词： distributed delay h∞ state estimation neural networks stability analysis

Reaction kinetic model for a recent co-produced water treatment technology

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Journal of Environmental Sciences 2011年第3期23卷 360-365页

作者： Abdulwahab m ali Tuwati mark A.Bentley Chemical & Petroleum Engineering University of Wyoming

With the increasing demand for fossil based energy and implementation of progressively strict environmental pollution control standards, treatment of a large amount of co-produced waters （CPWs） from fossil based energy production has become increasingly important. Removal of bicarbonate with h2SO4 has been recently studied as a simple and cost-effective method to decrease the alkalinity of CPWs. The present work investigates the kinetics of the reaction between h2SO4 and NahCO3, which could provide the base for scaling-up the CPW treatment technology. Based on the measured quantity change of the CO2 gas generated from the reaction between h2SO4 and NahCO3 with time under specified initial reaction conditions, the reaction orders with respect to h2SO4 and NahCO3 were determined. Experiments were also conducted within the temperature of 15-30℃ to find various global rate coefficients of the reaction to calculate the activation energy and the pre-exponential factor of the empirical Arrhenius form of the bicarbonate removal reaction, which are 197.7 kJ/mol and 3.13 × 1034 （mol-3.7 ×L3.7 ×sec^-1 ）, respectively.

关键词： fossil fuels water wastewater alkalinity bicarbonate