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Natural Propulsion with Lorentz Force and Nanoparticles in a Bioinspired Lopsided Ciliated Channel

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Journal of Bionic Engineering 2017年第1期14卷 172-181页

作者： Noreen sher Akbar Liaqat Ali Khan Zafar Hayat Khan Nazir Ahmed Mir DBS&H CEME National University of Sciences and Technology Islamabad Pakistan Basic Science Department Ripha International University Islamabad Pakistan Department of Mathematics University of Malakand Chakdara Dir (Lower) Khyber Pakhtunkhwa Pakistan

The transportation of biological and industrial nanofluids by natural propulsion like cilia movement and self-generated contraction-relaxation of flexible walls has tremendous applications in various fields. Inspired by multidisciplinary invention in this direction, a fuid mechanical model is proposed to study the Magneto-hydrodynamics （MHD） and heat transfer for nanofluids fabricated by the dispersion of nanoparticles in water as base fluid. The steady flow is induced by metachronal wave propulsion due to beating cilia. The flow regime is asymmetric channel. The flow is restricted under the low Reynolds number and long wavelength approximations. Cilia boundary conditions for velocity components are employed to find the exact solutions. The impacts of pertinent physical parameters on temperature profile, velocity profile, pressure, and stream lines are computed numerically. It is observed that velocity is inversely proportional to magnetic Reynolds number, Reynolds number, Strommer＇s number and velocity is directly proportional to flow rate. It is analyzed that temperature is inversely proportional to Strommer＇s number and magnetic Reynolds number and directly proportional to Brinkmann number and flow rate. The temperature is maximum at the center of the channel and it starts decreasing towards the boundary walls.

关键词： copper water nanoparticles induced magnetic field asymmetric ciliated channel

Modeling and Validation of Base Pressure for Aerodynamic Vehicles Based on Machine Learning Models

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2331-2352页

作者： Jaimon Dennis Quadros sher Afghan Khan Abdul Aabid Muneer Baig Senior Lecturer of Mechanical Engineering University of BoltonRAK Academic CenterRas Al Khaimah16038UAE Department of Mechanical and Aerospace Engineering Faculty of EngineeringInternational Islamic University MalaysiaSelangor53100Malaysia Department of Engineering Management College of EngineeringPrince Sultan UniversityRiyadh11586Saudi Arabia

The application of abruptly enlarged flows to adjust the drag of aerodynamic vehicles using machine learning models has not been investigated *** process variables(Mach number(M),nozzle pressure ratio(η),area ratio(α),and length to diameter ratio(γ))were numerically explored to address several aspects of this process,namely base pressure(β)and base pressure with cavity(βcav).In this work,the optimal base pressure is determined using the PCA-BAS-ENN based algorithm to modify the base pressure presetting accuracy,thereby regulating the base drag required for smooth flow of aerodynamic *** on the identical dataset,the GA-BP and PSO-BP algorithms are also compared to *** data for training and testing the algorithmswas derived using the regression equation developed using the Box-Behnken Design(BBD).The results show that the PCA-BAS-ENN model delivered highly accurate predictions when compared to the other two *** a result,the advantages of these results are two-fold,providing:(i)a detailed examination of the efficiency of different neural network algorithms in dealing with a genuine aerodynamic problem,and(ii)helpful insights for regulating process variables to improve technological,operational,and financial factors,simultaneously.

关键词： High speed flow Mach number machine learning PCA-BAS-ENN algorithm

A 526 mJ Subnanosecond Pulsed Hybrid-Pumped Nd：YAG Laser

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Chinese Physics Letters 2017年第7期34卷 105-108页

作者：石江鹏辛建国刘军陈家斌 sher Zaman School of Optoelectronics Beijing Institute of Technology Beijing 100081 School of Automation Beijing Institute of Technology Beijing 100081 Department of Physics Karakoram International University Gilgit 15100 Pakistan

A hybrid-pumped Nd：YAG pulse laser with a double-pass two-rod configuration is presented. The focal length of offset lens is particularly studied to compensate for the thermal lens effect and depolarization. For input pulse energy of 141 μJ with pulse duration of 754ps, the pulse laser system delivers 526mJ pulse energy and 728ps pulse width output at lO Hz with pulse profile shape preservation. The energy stability of the laser pulse is less than 3%, and the beam quality factor M2 is less than 2.26.

关键词： YAG length A 526 mJ Subnanosecond Pulsed Hybrid-Pumped Nd:YAG Laser Nd

Quantitative estimation of dust fall and smoke particles in Quetta Valley

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第7期7卷 542-547页

作者： SAMI Muhammad WASEEM Amir AKBAR sher Department of Chemistry University of Balochistan Quetta 87300 Pakistan

Tightening of air quality standards for populated urban areas has led to increasing attention to assessment of air quality management areas, where violation of air quality standards occurs, and development of control strategies to eliminate such vio-lation of air quality standards. The Quetta urban area is very densely built and has heavy motorized traffic. The increase of emis-sions mainly from traffic and industry are responsible for the increase in atmospheric pollution levels during the last years. The dust examined in the current study was collected by both deposit gauge and Petri dish methods at various sites of Quetta Valley. Smoke particles were obtained by bladder method from the exhausts of various types of motor vehicles. The concentration of lead found in the smoke ranged from 1.5×10?6 to 4.5×10?6.

关键词： Particulate matter (PM) Dust fall Smoke Lead Gasoline

EFFECT OF NANO-FILLER DISPERSION ON THE THERMAL,MECHANICAL AND WATER SORPTION PROPERTIES OF GREEN ENVIRONMENTAL POLYMER

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Chinese Journal of Polymer Science 2012年第5期30卷 735-743页

作者： sher Bahadar Khan Kalsoom Akhtar Jongchul Seo Haksoo Han Malik Abdul Rub Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah 21589P.O.Box 80203Saudi Arabia Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Division of Nano Sciences and Department of Chemistry Ewha Womans UniversitySeoul 120-750Korea Department of Packaging Yonsei UniversityWonju-siKangwondo 220-710Korea Department of Chemical and Biomolecular Engineering Yonsei University262 SeongsannoSeodaemun-guSeoul 120-749Korea Center of Excellence for Advanced Materials Research King Abdulaziz UniversityJeddah 21589P.O.Box 80203Saudi Arabia Chemistry Department Faculty of ScienceKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia

Partially exfoliated nanocomposite （2） has been synthesized by intercalation of poly（propylene carbonate）（PPC） into commercial clay, Cloisite 20B （PPC/C-20B）. Nanocomposite 2 was characterized phiso-chemically and exhibited high thermal, mechanical and anti-water sorption properties as compared to PPC and intercalated nanocomposite （1） of PPC/C- 20B having same amount of clay. TGA results revealed that the thermal decomposition temperature （Td, 50%） of 2 increased significantly, being 40 K and 17 K higher than that of pure PPC and 1, respectively, while DSC measurements indicated that the nano-filler dispersion of 2 increased the glass transition temperature from 21℃ to 31℃. Accordingly, 2 showed high elastic modulus, hardness and anti-water absorption capacity. These thermal, mechanical alad anti-water absorption improvements are of great importance for the application of PPC as packaging and biomaterials.

关键词： Poly(propylene carbonate) Cloisite 20B Nanocomposite Solution intercalation Thermal property Mechanicalproperty Water absorption property.

Heat transfer analysis of bi-viscous ciliary motion fluid

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International Journal of Biomathematics 2015年第2期8卷 219-231页

作者： Noreen sher Akbar Z. H. Khan DBS H CEMENational University of Sciences and Technology Islamabad Pakistan Department of Mathematics University of MalakandChakdara Dir. (Lower) Khyber Pakhtunkhwa Pakistan

The impulsion system of cilia motion is deliberated by biviscosity fluid model. The problem of two-dimensional motion of biviscosity fluid privileged in a symmetric channel with ciliated walls is considered. The features of ciliary structures are resolute by the supremacy of viscous effects above inertial possessions by the long-wavelength and low Reynolds approximation. Closed-form solutions for the longitudinal pressure gradient, temperature and velocities are obtained. The pressure gradient and volume flow rate for different values of the biviscosity are also premeditated. The flow possessions for the biviscosity fluid resolute as a function of the cilia and metachronal wave velocity.

关键词： Ciliary motion symmetric channel biviscosity fluid heat transfer exact solutions.

Design and optimization of electrochemical cell potential for hydrogen gas production

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Journal of Energy Chemistry 2021年第1期30卷 421-427,I0013页

作者： Nawar KAl-Shara Farooq sher Sania ZIqbal Oliver Curnick George ZChen Department of Chemical and Environmental Engineering Faculty of EngineeringUniversity of NottinghamUniversity ParkNottingham NG72RDUK School of Mechanical Aerospace and Automotive EngineeringFaculty of EngineeringEnvironmental and ComputingCoventry UniversityCoventry CV12JHUK Department of Biochemistry University of AgricultureFaisalabad 38000Pakistan Institute for Future Transport and Cities Coventry UniversityCoventry CV15FBUK Department of Chemical and Environmental Engineering Faculty of Science and EngineeringUniversity of Nottingham Ningbo ChinaUniversity ParkNingbo 315100China

This study deals with the optimization of best working conditions in molten melt for the production of hydrogen(H2) *** research has been carried out on how electrochemical process occurs through steam splitting via molten hydroxide.54 combinations of cathode,anode,temperature and voltage have been investigated for the optimization of best working conditions with molten hydroxide for hydrogen gas *** these electrochemical investigations were carried out at 225 to 300℃ temperature and 1.5 to 2.5 V applied voltage *** current efficiency of 90.5,80.0 and 68.6% has been achieved using stainless steel anodic cell with nickel,stainless steel and platinum working cathode *** nickel cathode,an increase in the current directly affected the hydrogen gas flow rate at *** can be hypothesized from the noted results that increase in current is directly proportional to operating temperature and applied *** values were noted when the applied voltages increased from 1.5 to 2.5 V at 300℃,the flow rate of hydrogen gas increased from 1.5 to 11.3 cm^(3) min^(-1),1.0 to 13 cm^(3) min^(-1) in case of electrolysis@stainless steel and@graphite anode *** is observed that the current efficiency of stainless steel anodic cell was higher than the graphite anodic ***,steam splitting with the help of molten salts has shown an encouraging alternate to current methodology for H2 fuel production.

关键词： Sustainable energy Splitting steam Electrolysis Hydrogen gas production Electrochemical cell and Variable cathodes

The Forecast of the Debris Flow Based on Hydrological Distribution Model: A Case Study of Qipan Gully,Wenchuan County,China

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The Forecast of the Debris Flow Based on Hydrological Distri...

作者： KHAN sher 西南科技大学

学位级别：硕士

泥石流是我国山区常见的自然现象,由于泥石流爆发迅速,来势凶猛,常伴有崩塌、滑坡及洪水等多重作用,破坏力大,每年都造成严重的人员伤亡和财产损失,阻碍经济的发展,因此合理有效的预报就变得尤为重要。本文以四川省汶川县七盘沟为例,采... 详细信息

泥石流是我国山区常见的自然现象,由于泥石流爆发迅速,来势凶猛,常伴有崩塌、滑坡及洪水等多重作用,破坏力大,每年都造成严重的人员伤亡和财产损失,阻碍经济的发展,因此合理有效的预报就变得尤为重要。本文以四川省汶川县七盘沟为例,采用SCS分布式水文模型结合土壤类型、坡度、土地利用类型等下垫面因素,推算流域的产汇流量,并以此为基础结合经验公式对泥石流暴发规模作了系统的研究,并与2013年7月11日实际发生的泥石流进行对比。结果显示:计算得到的清水洪峰流量和泥石流总量分别为136.75m/s和110.3×104m,其中泥石流总量与实测值相比,误差在5%以内。说明基于SCS水文模型进行泥石流预报具有一定的应用意义,预测结果可以促进泥石流工程防治的开展,为泥石流的防治和提供基础。

关键词： SCS水文模型产汇流七盘沟泥石流流量

Transient peristaltic diffusion of nanofluids: A model of micropumps in medical engineering

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Journal of Hydrodynamics 2018年第6期30卷 1001-1011页

作者： Dharmendra Tripathi Shashi Bhushan O.Anwar Bég Noreen sher Akbar Department of Science and Humanities National Institute of TechnologyUttarakhand–246174 India Department of Mechanical Engineering Manipal University Department of Aeronautical and Mechanical Engineering University of Salford DBS & H CEME National University of Sciences and TechnologyIslamabad Pakistan

Peristaltic micro-pumps offer an excellent mechanism for delivery of a variety of medicines including drugs, corneal solutions etc. The surge in deployment of nanoparticles in medicine has provided new potential for such pumps. In light of this we investigate the time-dependent peristaltic flow of nanofluids with diffusive effects through a finite non-uniform channel, this geometry being more representative of real micro-pumps. Creeping flow is taken into account(inertial forces are small compared with viscous forces) i.e., Reynolds number is low(Re< 1) and wavelength is also taken to be very large. The Buongiorno formulation for nanofluids is employed with an Oberbeck-Boussinesq approximation. Closed-form solutions are developed for the non-dimensional governing equations subject to physically realistic boundary conditions. Mathematica symbolic software is employed to evaluate the evolution of nanoparticle fraction, temperature, axial velocity, transverse velocity and pressure difference distribution along the length of the pump channel with variation in thermal Grashof number, basic-density(species i.e., mass) Grashof number, Brownian motion parameter and thermophoresis parameter.

关键词： Unsteady flow peristaltic pumps nanofluids medical engineering diffusive process grashof number thermophoresis