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    A numerical approach for analyzing the electromagnetohydrodynamic flow through a rotating microchannel

    , Article Arabian Journal for Science and Engineering ; Volume 48, Issue 3 , 2023 , Pages 3765-3781 ; 2193567X (ISSN) Ali, K ; Ahmad, A ; Ahmad, S ; Ahmad, S ; Jamshed, W ; Sharif University of Technology
    Institute for Ionics  2023
    Abstract
    The purpose of the paper is to develop a mathematical foundation for exploring the complex interaction of Coriolis and Lorentz forces with the electromagnetohydrodynamic (EMHD) flow of a power-law fluid inside a microchannel with wall slip condition. Both the Lorentz and Coriolis forces act orthogonally to each other. Mathematical modeling of the problem is based on a set of classical Maxwell and Navier–Stokes equations, which are subsequently solved numerically by employing an implicit finite difference methodology. The numerical solution thus obtained has been found to be in an excellent agreement correlation with the ones reported in the scientific literature, for some limiting cases. A... 

    Effect of long-term, exogenous administration of oxytocin on milk production, composition, somatic cell count, and progesterone in postpartum Nili-Ravi buffalo

    , Article South African Journal of Animal Science ; Volume 54, Issue 1 , 2024 , Pages 37-46 ; 03751589 (ISSN) Murtaza, S ; Sattar, A ; Ahmad, N ; Khan, I. R ; Ijaz, M ; Ahmad, T ; Farooq, A. A ; Basit, M. A ; Javid, M. A ; Saleem, M. U ; Ahmad, J ; Zia, A ; Azam, B ; Sharif University of Technology
    2024
    Abstract
    This study sought to explore the effect of the administration of long-term, exogenous oxytocin on buffalo milk. In this study, newly-calved postpartum buffaloes (Nili-Ravi) (n = 24) were divided equally into three groups: (control without oxytocin – CON, 10 i.u. oxytocin – LOW, 30 i.u. oxytocin – HIGH). Oxytocin was injected twice a day before each 154-day milking. Milk production, milk composition, somatic cell counts, and progesterone (P4) were evaluated daily, weekly, and fortnightly, respectively. Results revealed that the HIGH group produced high milk production and pH values, but lower milk density than the CON and LOW groups. The HIGH group and LOW group had higher milk fat and... 

    Conceptual, legal, and ethical considerations in physician-assisted suicide: an overview

    , Article UUM Journal of Legal Studies ; Volume 15, Issue 2 , 2024 , Pages 707-744 ; 2229984X (ISSN) Ahmad, N ; Masum, A ; Ali, A. W ; Sharif University of Technology
    2024
    Abstract
    Physician-assisted suicide (PAS) remains a contentious and highly debated topic within medical, legal, and ethical spheres. The complex issue of (PAS) raises significant inquiries regarding patient autonomy and societal norms. Ambiguities in conceptual, legal, and ethical aspects impede policy formulation, leading to unequal access and apprehensions about patient welfare and confidence. This article provides a thorough examination of assisted suicide, exploring its legal, ethical, and medical dimensions. It aims to facilitate informed dialogue and stimulate further investigation into the legal framework and ethical considerations surrounding this contentious issue. Through a library-based... 

    The jus ad bellum and jus ad bello predicament in the context of Israel – Hamas conflict

    , Article Legal Transformation in Muslim Societies ; Volume 1, Issue 1 , 2024 , Pages 130-158 ; 30290961 (ISSN) Ahmad, N ; Ali, A. W ; Sharif University of Technology
    ResearchGate  2024
    Abstract
    A conflict acquires legal justification under international law if it adheres to the fundamentals of both Jus ad Bellum (conditions under which States may resort to war) and Jus in Bello (the law that governs how warfare is conducted). Jus ad Bellum is delineated by the United Nations Charter of 1945 and establishes a fundamental prohibition against using force between sovereign states. It incorporates exceptions for self-defence situations and actions authorised by the United Nations. Jus in Bello refers to the legal principles that regulate the conduct of parties engaged in armed conflicts. It aims to reduce human suffering by protecting and assisting all individuals impacted by these... 

    Investigation of the combination of TiO2 nanoparticles and drag reducer polymer effects on the heat transfer and drag characteristics of nanofluids

    , Article Canadian Journal of Chemical Engineering ; Volume 96, Issue 6 , 2018 , Pages 1430-1440 ; 00084034 (ISSN) Paryani, S ; Ramazani Ahmad, S. A ; Sharif University of Technology
    Wiley-Liss Inc  2018
    Abstract
    To compensate for drag increment due to the addition of nanoparticles to heat-transfer fluids, it seems that one could add drag reducer polymeric agents to these fluids. So, in this work, experiments were carried out for solutions of two types of polyacrylamide (FLOPAAM 3330S and FLOPAAM 3630S) at three distinct concentrations (25, 40, and 55 ppm), and TiO2-water nanofluid at concentrations of 0.015, 0.02, 0.025, and 0.03 L/L. The steady state turbulent convective heat transfer and the friction factor of the suspension of TiO2 in a dilute solution of very high molecular weight, polyacrylamide (hybrid fluid), in a coiled tube were analyzed. Experimental measurements were carried out from a... 

    Convection driven flow between moving diska- A non-linear approach for modelling thermal radiation

    , Article Scientia Iranica ; Volume 31, Issue 16 , 2024 , Pages 1402-1419 ; 10263098 (ISSN) Ali, K ; Ahmad, A ; Ahmad, S ; Sharif University of Technnology
    Scientia Iranica  2024
    Abstract
    Flows involving two disks have significant applications in heat exchangers, rotating machinery parts, data storage devices, oceanography and viscometers. In this investigation, heat and mass transfer characteristics are examined in Casson flow between two orthogonally moving disks, with nonlinear thermal radiation under the slip and convective conditions, using the powerful tool of similarity transformation. A MATLAB code, based on quasi-linearization, has been developed for the numerical study. It is observed that, when the disks are receding, the disk expansion ratio raises the velocity profile near the center of the region between the two disks. The trend is, however, reversed when the... 

    Micro-structured fluid within a channel under static and oscillatory pressure gradients: A novel Darcy-Forchheimer flow investigation

    , Article Engineering Science and Technology, an International Journal ; Volume 47 , 2023 ; 22150986 (ISSN) Li, Y ; Ali, K ; Ahmad, S ; Ahmad, S ; Jamshed, W ; Abd Elmonem, A ; Amjad, A ; El Din, S. M ; Sharif University of Technology
    Elsevier B.V  2023
    Abstract
    The pertinence and importance of Darcy-Forchheimer flows can be found in large spectrum of engineering, biological and technological mechanisms like solar absorption and filtration, drainage problems, solar cells, ground stream hydrology, solar panels, irrigation and so forth. The major concern of this study is to interpret that how much a Darcy-Forchheimer flow of a micro-structured fluid (e.g., micropolar fluid) within a channel is influenced by the combined effects of static and oscillatory pressure gradients. Numerical treatment is carried out via three steps explicit Runge-Kutta method. Impacts of the preeminent parameters on the flow, mass and heat transport features of the problem are... 

    Advances in limitations and opportunities of clean biofuel production to promote decarbonization

    , Article Fuel ; Volume 342 , 2023 ; 00162361 (ISSN) Khawaja, A.S ; Zaheer, M. A ; Ahmad, A ; Mirani, A. A ; Ali, Z ; Sharif University of Technology
    Elsevier Ltd  2023
    Abstract
    Factors such as higher fuel prices, limited and geologically posited fossil fuel resources along with the impact of fossil fuels on global warming are highly unsustainable for growing economies around the globe. For this reason, an unconventional sustainable energy root is desired. In recent years, biodiesel has gained much consideration because of its similar combustion properties like fossil fuels and its synthesis from edible and non-edible oils via a catalytic process. Various catalysts (homogeneous and heterogeneous in nature) have been investigated for sustainable and green production of biodiesel. The heterogeneous catalyst calcium oxide is an abundant, cheap and has a high activity... 

    Novel thermal aspects of hybrid nanoparticles Cu-TiO2 in the flow of ethylene glycol

    , Article International Communications in Heat and Mass Transfer ; Volume 129 , 2021 ; 07351933 (ISSN) Ahmad, S ; Ali, K ; Faridi, A. A ; Ashraf, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Hybrid nanoparticles possess better chemical stability, mechanical resistance, thermal conductivity, physical strength and so forth as equated to pure nanoparticles. The present work describes the novel features of hybrid nanoparticles such as Titanium oxide (TiO2) and Copper (Cu) in the flow of Ethylene glycol (EG) under the induced magnetic field environment. The analysis covers the features of both pure nanofluid Cu/EG and hybrid nanofluid Cu-TiO2/EG. The concentration equation is amended by the activation energy term. The amalgamation of Cu-TiO2/EG exhibits improved and embellished thermal characteristics. A persuasive numerical technique named “Successive over Relaxation” is used to... 

    Novel thermal aspects of hybrid nanoparticles Cu-TiO2 in the flow of ethylene glycol

    , Article International Communications in Heat and Mass Transfer ; Volume 129 , 2021 ; 07351933 (ISSN) Ahmad, S ; Ali, K ; Faridi, A. A ; Ashraf, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Hybrid nanoparticles possess better chemical stability, mechanical resistance, thermal conductivity, physical strength and so forth as equated to pure nanoparticles. The present work describes the novel features of hybrid nanoparticles such as Titanium oxide (TiO2) and Copper (Cu) in the flow of Ethylene glycol (EG) under the induced magnetic field environment. The analysis covers the features of both pure nanofluid Cu/EG and hybrid nanofluid Cu-TiO2/EG. The concentration equation is amended by the activation energy term. The amalgamation of Cu-TiO2/EG exhibits improved and embellished thermal characteristics. A persuasive numerical technique named “Successive over Relaxation” is used to... 

    Investigation of hybrid ultrasonic machining process of Nomex honeycomb composite using a toothed disc cutter

    , Article Ultrasonics ; Volume 141 , 2024 ; 0041624X (ISSN) Mughal, K. H ; Qureshi, M. A. M ; Jamil, M. F ; Ahmad, S ; Ahmad Khalid, F ; Qaiser, A. A ; Maqbool, A ; Raza, S. F ; Zhang, J ; Sharif University of Technology
    2024
    Abstract
    Nomex honeycomb composite (NHC) has been increasingly used in the automotive, aerospace and defence applications due to its excellent thermal and mechanical properties. Its complex cellular hexagonal thin-walled configuration along with heterogeneous, soft and brittle nature pose substantial processing defects such as burr formation, tearing of walls, surface roughness, dimensional inaccuracy and low machining quality during conventional machining (CM). These surface defects have a substantial influence on the operating life and functional performance of its sandwiched structural members. Hybrid ultrasonic vibration assisted machining (HUSVAM) technology has been introduced to overcome such... 

    Thermal attributes of sodium alginate (Na.C6H7O6) based binary and ternary hybrid nanofluids under activation energy and induced magnetic field environment

    , Article Case Studies in Thermal Engineering ; Volume 59 , 2024 ; 2214157X (ISSN) Li, S ; Leng, Y ; Atta, G ; Ahmad, S ; Ali, K ; Idris, S. A ; Ahmad, H ; Sharif University of Technology
    2024
    Abstract
    Ternary hybrid nanofluids possess several potential applications in the modern science beyond just the heat transfer efficiency. A continuous research and advancements on binary and ternary hybrid nanofluids might lead towards new developments in many technological and scientific zones. Ongoing research interprets and distinguishes the novel attributes of the sodium alginate (Na.C6H7O6) based unary, binary and ternary nanofluids through a porous medium under induced magnetic field environment. The nano-composition of single-wall carbon nanotubes (SWCNT) with silver (Ag) and molybdenum dioxide (MoS2) gives rise to the binary (SWCNT-Ag/Na.C6H7O6) and ternary hybrid (SWCNT-Ag-MoS2/Na.C6H7O6)... 

    Manufacture of Smart Drug Delivery System with UCST Polymers

    , M.Sc. Thesis Sharif University of Technology Karimi, Ahmad Reza (Author) ; Ramazani, Ahmad (Supervisor)
    Abstract
    Smart heat-sensitive polymers play a unique role in drug delivery systems due to reversible behavior in response to environmental changes, especially temperature changes. Among the heat-sensitive polymers, UCST polymers due to their specific behavior and very little-known polymers with this feature are the subject of many new researches. In the present study, New designed temperature-sensitive polymers with UCST capability based on acrylamide and vinyl acetate were synthesized. These copolymers were synthesized in different percentages of acrylamide by free radical polymerization in solution conditions. All polymers compounds were characterized by H-NMR, FT-IR, DSC and GPC measurements. The... 

    The effects of thymus plant extracts on single breast cancer cell morphology in the microfluidic channel

    , Article 2018 IEEE EMBS Conference on Biomedical Engineering and Sciences, IECBES 2018, 3 December 2018 through 6 December 2018 ; 2019 , Pages 647-651 ; 9781538624715 (ISBN) Ahmad, M. R ; Mansor, M. A ; Alsadat Rad, M ; Soo-Beng Khoo, A ; Ahmad, M ; Marzuki, M ; Physiological Measurement; Sarawak Convention Bureau ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2019
    Abstract
    Microfluidics based systems could be useful for drug discovery as they allow for miniaturization and could potentially be run as multiple parallel cell based assays. Such miniaturization allows assays at single cell level and reduces the amount of test material needed, which, in the case of natural product extracts, simplifies the preparation. Thyme species extracts have been reported to show some promising anti-cancer effects. In the present work, we used a microfluidics based system to study the effects of Thymus kotschyanusm Boiss plant extract on two human breast cancer cells lines which are MDA-MB-231 and MCF-7. For better understanding a single cancer cell death mechanism and a flow... 

    A novel field applicable mud formula with enhanced fluid loss properties in High Pressure-High temperature well condition containing pistachio shell powder

    , Article Journal of Petroleum Science and Engineering ; Volume 162 , March , 2018 , Pages 378-385 ; 09204105 (ISSN) Davoodi, S ; Ramazani Ahmad, S. A ; Jamshidi, S ; Fellah Jahromi, A ; Sharif University of Technology
    Elsevier B.V  2018
    Abstract
    Sustainable technologies are the main concerns of the 21st century modified oilfield industries. The insufficiency of conventional drilling fluid formulations with a combination of hardly degradable hazardous chemicals as additives raise the demands of field-applicable innovative and environmentally friendly methods. Pistachio Shell discards as degradable wastes, which can intellectually apply in drilling fluid formulation. The experimental oilfield investigations of utilizing pistachio shell powder prove the significant enhancement of rheological properties, reduction of fluid loss and mud cake thickness in both API (Low Pressure —Low Temperature) and High Pressure—High Temperature (HPHT)... 

    Expectation propagation for large scale Bayesian inference of non-linear molecular networks from perturbation data

    , Article PloS one ; Volume 12, Issue 2 , 2017 , Pages e0171240- ; 19326203 (ISSN) Narimani, Z ; Beigy, H ; Ahmad, A ; Masoudi Nejad, A ; Fröhlich, H ; Sharif University of Technology
    2017
    Abstract
    Inferring the structure of molecular networks from time series protein or gene expression data provides valuable information about the complex biological processes of the cell. Causal network structure inference has been approached using different methods in the past. Most causal network inference techniques, such as Dynamic Bayesian Networks and ordinary differential equations, are limited by their computational complexity and thus make large scale inference infeasible. This is specifically true if a Bayesian framework is applied in order to deal with the unavoidable uncertainty about the correct model. We devise a novel Bayesian network reverse engineering approach using ordinary... 

    Differential topology of adiabatically controlled quantum processes

    , Article Quantum Information Processing ; Volume 12, Issue 3 , March , 2013 , Pages 1515-1538 ; 15700755 (ISSN) Jonckheere, E. A ; Rezakhani, A. T ; Ahmad, F ; Sharif University of Technology
    2013
    Abstract
    It is shown that in a controlled adiabatic homotopy between two Hamiltonians, H0 and H1, the gap or "anti- crossing" phenomenon can be viewed as the development of cusps and swallow tails in the region of the complex plane where two critical value curves of the quadratic map associated with the numerical range of H0 + i H 1 come close. The "near crossing" in the energy level plots happens to be a generic situation, in the sense that a crossing is a manifestation of the quadratic numerical range map being unstable in the sense of differential topology. The stable singularities that can develop are identified and it is shown that they could occur near the gap, making those singularities of... 

    The Role of Treaties in Islamic and Modern International Law:A Comparative Analysis

    , Article Manchester Journal of Transnational Islamic Law and Practice ; Volume 20, Issue 1 , 2024 , Pages 164-186 ; 26336626 (ISSN) Ahmad, N ; Asmad, A. B ; Ariffin, D. I ; Sharif University of Technology
    2024
    Abstract
    This article aims to offer a comparative understanding of Islamic law of treaties with respect to modern treaty law and practice. It presents a theoretical and historical comparison of classical jurists’ viewpoints on treaties, emphasising their enduring significance in today’s society. The treaty of Hudaybiyyahh, which was signed between Muslims and non-Muslims, is often referenced in Islamic law as a starting point to discuss the concept of treaties. This treaty has had a significant impact in protecting the Muslim community from potential dangers to their religion and possessions. This article compares the features of treaties in Islamic law and international law and illustrates the... 

    Numerical study of lorentz force interaction with micro structure in channel flow

    , Article Energies ; Volume 14, Issue 14 , 2021 ; 19961073 (ISSN) Ahmad, S ; Ali, K ; Ahmad, S ; Cai, J ; Sharif University of Technology
    MDPI AG  2021
    Abstract
    The heat transfer Magnetohydrodynamics flows have been potentially used to enhance the thermal characteristics of several systems such as heat exchangers, electromagnetic casting, adjusting blood flow, X-rays, magnetic drug treatment, cooling of nuclear reactors, and magnetic devices for cell separation. Our concern in this article is to numerically investigate the flow of an incompressible Magnetohydrodynamics micropolar fluid with heat transportation through a channel having porous walls. By employing the suitable dimensionless coordinates, the flow model equations are converted into a nonlinear system of dimensionless ordinary differential equations, which are then numerically treated for... 

    Creating sentiment lexicon for sentiment analysis in Urdu: The case of a resource-poor language

    , Article Expert Systems ; Volume 36, Issue 3 , 2019 ; 02664720 (ISSN) Asghar, M. Z ; Sattar, A ; Khan, A ; Ali, A ; Masud Kundi, F ; Ahmad, S ; Sharif University of Technology
    Blackwell Publishing Ltd  2019
    Abstract
    The sentiment analysis (SA) applications are becoming popular among the individuals and organizations for gathering and analysing user's sentiments about products, services, policies, and current affairs. Due to the availability of a wide range of English lexical resources, such as part-of-speech taggers, parsers, and polarity lexicons, development of sophisticated SA applications for the English language has attracted many researchers. Although there have been efforts for creating polarity lexicons in non-English languages such as Urdu, they suffer from many deficiencies, such as lack of publically available sentiment lexicons with a proper scoring mechanism of opinion words and modifiers....