Mathematical analysis of bio-convective micropolar nanofluid

Sohail Nadeem,Muhammad Naveed Khan,Noor Muhammad,Shafiq Ahmad 한국CDE학회 2019 Journal of computational design and engineering Vol.6 No.3

The present investigation concentrates on three dimensional unsteady forced bio-convection flow of a viscous fluid. An incompressible flow of a micropolar nanofluid encloses micro-organisms past an expo-nentially stretching sheet with magnetic field is analyzed. By employing convenient transformation the partial differential equations are converted into the ordinary differential equations which are non-linear. By using shooting method to solved these equations numerically. The influence of the determining parameters on the velocity, temperature, micro-rotation, nanoparticle volume fraction, microorganism are incorporated. The skin friction, heat transfer rate, and the microorganism rate are analyzed. The results depicts that the value of the wall shear stress and Nusselt number are declined while an enhance-ment take place in the microorganism number. The slip parameters increases the velocity, thermal energy, and microorganism number consequentially. The present investigation are important in improv-ing achievement of microbial fuel cells

Boundary layer flow of nanofluid over an exponentially stretching surface

Nadeem, Sohail,Lee, Changhoon Springer 2012 NANOSCALE RESEARCH LETTERS Vol.7 No.1

<P>The steady boundary layer flow of nanofluid over an exponential stretching surface is investigated analytically. The transport equations include the effects of Brownian motion parameter and thermophoresis parameter. The highly nonlinear coupled partial differential equations are simplified with the help of suitable similarity transformations. The reduced equations are then solved analytically with the help of homotopy analysis method (HAM). The convergence of HAM solutions are obtained by plotting <I>h</I>-curve. The expressions for velocity, temperature and nanoparticle volume fraction are computed for some values of the parameters namely, suction injection parameter <I>α</I>, Lewis number <I>Le</I>, the Brownian motion parameter <I>Nb </I>and thermophoresis parameter <I>Nt</I>.</P>

Swirling flow analysis of Eyring–Powell fluid between coaxial disks with variable property

Nadeem Sohail,Ishtiaq Bushra,Akkurt Nevzat,Eldin Sayed M 한국CDE학회 2023 Journal of computational design and engineering Vol.10 No.2

The main objective of this study is to examine an unsteady swirling flow of a non-Newtonian Eyring–Powell fluid between two coaxial disks. The lower and upper disks are considered to rotate with different angular velocities. The three-dimensional axisymmetric flow phenomenon and heat transfer mechanism are observed with the consequences of the magnetic field and variable thermal conductivity of the fluid. The variable thermal conductivity is taken to be dependent on the fluid temperature. The implementation of the Von Karman similarity transformations on the constituting equations of the flow phenomenon yields the dimensionless system of the non-linear equations. An optimal homotopy analysis technique is adopted to obtain analytical solutions for highly non-linear equations. In view of the same and opposite directions of disks rotation, the various aspects of the flow system corresponding to the pertinent parameters are discussed with physical significance. The obtained results indicate that both radial and axial fields are the escalating functions of the Eyring–Powell fluid parameter. Moreover, the heat transfer rate enhances with the improving variable thermal conductivity parameter.

Implementation of Class-Based Low Latency Fair Queueing (CBLLFQ) Packet Scheduling Algorithm for HSDPA Core Network

( Sohail Ahmed ),( Malik Muhammad Asim ),( Nadeem Qaisar Mehmood ),( Mubashir Ali ),( Babar Shahzaad ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.2

To provide a guaranteed Quality of Service (QoS) to real-time traffic in High-Speed Downlink Packet Access (HSDPA) core network, we proposed an enhanced mechanism. For an enhanced QoS, a Class-Based Low Latency Fair Queueing (CBLLFQ) packet scheduling algorithm is introduced in this work. Packet classification, metering, queuing, and scheduling using differentiated services (DiffServ) environment was the points in focus. To classify different types of real-time voice and multimedia traffic, the QoS provisioning mechanisms use different DiffServ code points (DSCP).The proposed algorithm is based on traffic classes which efficiently require the guarantee of services and specified level of fairness. In CBLLFQ, a mapping criterion and an efficient queuing mechanism for voice, video and other traffic in separate queues are used. It is proved, that the algorithm enhances the throughput and fairness along with a reduction in the delay and packet loss factors for smooth and worst traffic conditions. The results calculated through simulation show that the proposed calculations meet the QoS prerequisites efficiently.

A review of carbon-based materials and their coating techniques for biomedical implants applications

Hassan Sadia,Nadeem Aroosa Younis,Qaiser Hafsah,Kashif Amer Sohail,Ahmed Ammad,Khan Khushbukhat,Altaf Amna 한국탄소학회 2023 Carbon Letters Vol.33 No.4

Carbon-based materials have emerged as an excellent class of biomedical materials due to their exceptional mechanical properties, lower surface friction, and resistance to wear, tear, and corrosion. Experimental studies have shown the promising results of carbon-based coatings in the field of biomedical implants. The reasons for their successful applications are their ability to suppress thrombo-inflammatory reactions which are evoked as an immune response due to foreign body object implantation. Different types of carbon coatings such as diamond-like carbon, pyrolytic carbon, silicon carbide, and graphene have been extensively studied and utilized in various fields of life including the biomedical industry. Their atomic arrangement and structural properties give rise to unique features which make them suitable for multiple applications. Due to the specificity and hardness of carbon-based precursors, only a specific type of coating technique may be utilized for nanostructure development and fabrication. In this paper, different coating techniques are discussed which were selected based on the substrate material, the type of implant, and the thickness of coating layer. Chemical vapor deposition-based techniques, thermal spray coating, pulsed laser deposition, and biomimetic coatings are some of the most common techniques that are used in the field of biomaterials to deposit a coating layer on the implant. Literature gathered in this review has significance in the field of biomedical implant industry to reduce its failure rate by making surfaces inert, decreasing corrosion related issues and enhancing biocompatibility.

Determination of Bergenin in Different Parts of Bergenia ciliata using a Validated RP-HPLC Method

Ejaz Ali,Khalid Hussain,Nadeem Irfan Bukhari,Najma Arshad,Amjad Hussain,Nasir Abbas,Sohail Arshad,Sajida Parveen,Naureen Shehzadi,Shaista Qamar,Abida Qamar 한국생약학회 2021 Natural Product Sciences Vol.27 No.1

Bergenia ciliata (Family: Saxifragaceae) is a folklore remedy for the treatment of various ailments in Asian countries. Bergenin (1) has been isolated as an active constituent in many studies, however, the amount of bergenin has not been determined in all parts of the plant. A simple RP-HPLC method was developed to determine the amount of bergenin in methanol extracts of leaves, rhizomes and roots of the plant. Separation was achieved on an Agilent Eclipse XDB-C18 column maintained at 25 oC using isocratic solvent system (water: methanol: acetic acid; 62.5:37:0.5 v/v/v) adjusted at pH 2 0 at a flow rate of 1.0 mL/min. and detected at 275 nm. Correlation coefficient (0.9952) showed linearity of concentration (5-200 μg/mL) and response. The values of LOD (0.00947 μg/mL) and LOQ (0.02869 μg/mL) indicated that method was sensitive. The recovery of bergenin was 99.99-100% indicating accuracy of method. The methanol extract of rhizomes contained higher amount of bergenin (19.4%) than roots (9.2%) and leaves (6.9%). It is concluded that methanol extract of rhizomes is a better source of bergenin than other parts of the plant. The findings are useful for standardization of bergenin containing extracts and herbal preparations.

Heat transfer analysis of Carreau–Yasuda nanofluid flow with variable thermal conductivity and quadratic convection

Akbar Asia Ali,Awan Aziz Ullah,Nadeem Sohail,Ahammad N Ameer,Raza Nauman,Oreijah Mowffaq,Guedri Kamel,Allahyani Seham Ayesh 한국CDE학회 2024 Journal of computational design and engineering Vol.11 No.1

Brownian motions and Thermophoresis are primary sources of nanoparticle diffusion in nanofluids, having substantial implications for the thermo-physical characteristics of nanofluids. With such a high need, the 2D, laminar MHD (Magnetohydrodynamic) quadratic convective stream of Carreau–Yasuda nano liquid across the stretchy sheet has been reported. The flow is caused by surface stretching. The principal purpose of this extensive study is to enhance thermal transmission. The effects of variable thermal conductivity and heat source are considered as well. The governing boundary layer equations are transmuted using similarity parameters into a series of non-linear ODEs (ordinary differential equations). The bvp4c algorithm is adopted to fix the translated system numerically. The effects of prominent similarity variables over the temperature, velocity and concentration field are graphically visualized and verified via tables. It explored that fluid’s speed diminishes for the more significant inputs of the magnetic coefficient, Brownian motion coefficient and Prandtl number. The thermal efficiency is improved for larger values of thermophoretic constant, varying thermal conductance and heat-generating parameters. The concentration field has proved to be a decreasing function of nanofluid constants.

THREE-DIMENSIONAL BOUNDARY-LAYER FLOW OVER AN EXPONENTIALLY STRETCHING SURFACE WITH THERMAL RADIATION

Malik, Muhammad Y.,Rehman, Sajjad,Nadeem, Sohail Begell House Inc. 2015 Heat Transfer Research Vol.46 No.6

Designing polyoxometalate based hybrid catalysts for efficient removal of hazardous sulfur from fuel via heterogeneous oxidative desulfurization

Sadaf Ul Hassan,Sadaf Ahmad,Muhammad Asim Farid,Sohail Nadeem,Zulfiqar Ali,Rashid Abro,Aysha Mohyuddin,Muhammad Shahid Nazir,Murid Hussain,박영권 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.116 No.-

Hydrodesulfurization is a common but less effective technique to remove sulfur content of oils due to severe operating conditions of temperature, pressure and cost. Oxidative desulfurization(ODS) is preferable due to low cost and mild operating conditions. Coupling of the extractive catalytic desulfurization with the ODS give rise to extractive catalytic oxidative desulfurization(ECODS), a more promising for the elimination of sulfur contents of fuel oil. Herein we present by polyoxometalate based hybrids, [H2TPP][K5BVW11O40]•2CH3CN•2H2O (1), [H2TPP]2[K3BVW11O40]•CH3CN•3H2O (2), and [H2TPP]3[KBVW11O40]•2CH3CN (3) for efficient ECODS of hazardous model fuel. These were synthesized by facile method and characterized by elemental analysis, inductive couple plasma, powder X-ray diffraction analysis, thermo-gravimetric/differential thermal analysis, fourier transform infrared, and UV–visible analysis. These polyoxometalate based hybrids contain cations [H2TPP]2+(organic) and [BVW11O40]7−(inorganic) with stoichiometric ratios(i.e., 1:1, 2:1, 3:1). The stoichiometry of these hybrids was also established by Job’s analysis which agreed well with the results of TG-DTA and elemental analyses. Interestingly, an increase in catalytic efficiency is observed with increase of organic cations. The maximum ∼99.5 % conversion of dibenzothiophene at 60 °C after 2 h has been achieved with hybrid 3 which could be employed up to ten cycles without a significant decrease in efficiency.