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SI Engine Fueled with Gasoline, CNG and CNG-HHO Blend: Comparative Evaluation of Performance, Emission and Lubrication Oil Deterioration

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Journal of Thermal Science 2021年第4期30卷 1199-1211页

作者： usman Muhammad HAYAT Nasir BHUTTA Muhammad Mahmood Aslam Department of Mechanical Engineering University of Engineering and TechnologyLahore 54890Pakistan

Hydroxy gas (HHO) is one of the potential alternative fuels for spark ignition (SI) engine,notably due to simultaneous increase in engine performance and reduction in exhaust ***,impact of HHO gas on lubrication oil for longer periods of engine operation has not yet been *** study focuses on investigation of the effect of gasoline,CNG and CNG-HHO blend on lubrication oil deterioration along with engine performance and emissions in SI *** unit produces HHO gas at 4.72 L/min by using 6 g/L of KOH in the aqueous *** was supplied to the test engine at a pressure of 0.11 MPa using an electronically controlled solenoid *** tests were carried out at different speeds at 80%open throttle condition and various performance parameters such as brake power (BP),brake specific fuel consumption(BSFC),brake thermal efficiency (BTE),exhaust gas temperature and exhaust emissions (HC,CO_(2),CO and NO_(x))were *** addition,various lubrication oil samples were extracted over 120 h of engine running while topping for drain out volume and samples were analyzed as per ASTM ***-HHO blend exhibited better performance i.e.,15.4%increase in average BP in comparison to CNG,however,15.1%decrease was observed when compared to ***-HHO outperformed gasoline and CNG in the case of HC,CO_(2),CO and brake specific fuel consumption (31.1%decrease in comparison to gasoline).On the other hand,CNG-HHO produced higher average NO_(x) (12.9%) when compared to CNG ***,lubrication oil condition(kinematic viscosity,water contents,flash point and total base number (TBN)),wear debris (Iron (Fe),Aluminum(Al),Copper (Cu),Chromium (Cr)) and additives depletion (Zinc (Zn),Calcium (Ca)) presented a significant degradation in the case of CNG-HHO blend as compared to gasoline and *** oil analyses illustrated 19.6%,12.8%and 14.2%decrease in average viscosity,flash point and TBN for CNG-HHO blend ***,

关键词： spark ignition engine compressed natural gas hydrogen lubrication oil deterioration emission

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Theoretical Investigation of Two-Dimensional Nonlinear Radiative Thermionics in Nano-MHD for Solar Insolation:A Semi-Empirical Approach

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 751-776页

作者： usman Inayat Shaukat Iqbal Tareq Manzoor School of Systems and Technology University of Management and TechnologyLahore54000Pakistan Energy Research Centre COMSATS University IslamabadLahore CampusLahore54000Pakistan

In this contemporary study,theoritical investigation of nanofluidic model is ***-dimensional nanomaterials based mixed flow is considered *** solar radiative heat transport properties have been investigated over a nonlinearly stretched wall in the presence of magneto-hydrodynamic(MHD),by innovative application of semi analytical“optimal homotopy asymptotic method(OHAM)”.OHAM does not require any discretization,linearization and small parameter *** describes extremely precise 1^(st)/2^(nd) order solutions without the need of computing further higher order terms,therefore,fast convergence is *** governing model is transformed into system of ordinary differential equations(ODEs)by exploitation of similarity *** study the significance of radiation parameter alongwith thermophoresis parameter,a semi analytical solver is applied to the transformed *** this work,Brownianmotion,influence ofmagnetic field,Lewis number,Prandtl number,Eckert number and Biot number have investigated on velocity,temperature and nanoparticle concentration *** study provides sufficient number of graphical representations to demonstrate the inspiration of mentioned parameters.

关键词： Magneto-hydrodynamic(MHD) OHAM nanofluid solar radiative stretched wall

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Computational analysis for fractional characterization of coupled convection-diffusion equations arising in MHD fows

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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 669-692页

作者： M.HAMID M.usman Zhenfu TIAN School of Mathematics and Statistics Nanjing University of Information Science and TechnologyNanjing 210044China Department of Aeronautics and Astronautics Fudan UniversityShanghai 200433China School of Mathematical Sciences Jiangsu UniversityZhenjiang 212013Jiangsu ProvinceChina

The work is devoted to the fractional characterization of time-dependent coupled convection-diffusion systems arising in magnetohydrodynamics(MHD)*** time derivative is expressed by means of Caputo’s fractional derivative concept,while the model is solved via the full-spectral method(FSM)and the semi-spectral scheme(SSS).The FSM is based on the operational matrices of derivatives constructed by using higher-order orthogonal polynomials and collocation *** SSS is developed by discretizing the time variable,and the space domain is collocated by using equal points.A detailed comparative analysis is made through graphs for various parameters and tables with existing *** contour graphs are made to show the behaviors of the velocity and magnetic *** proposed methods are reasonably efficient in examining the behavior of convection-diffusion equations arising in MHD flows,and the concept may be extended for variable order models arising in MHD flows.

关键词： higher-dimensional Chelyshkov polynomial(CP) time-dependent magneto-hydrodynamics(MHD)flow fractional convection-diffusion model convergence stability and error bound finite difference and higher-order scheme

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FORCED OSCILLATIONS OF A CLASS OF NONLINEAR DISPERSIVE WAVE EQUATIONS AND THEIR STABILITY

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Journal of Systems Science & Complexity 2007年第2期20卷 284-292页

作者： Muhammad usman Bingyu ZHANG Department of Mathematical Sciences University of Cincinnati Cincinnati Ohio 45221-0025 USA

It has been observed in laboratory experiments that when nonlinear dispersive waves are forced periodically from one end of undisturbed stretch of the medium of propagation, the signal eventually becomes temporally periodic at each spatial point. The observation has been confirmed mathematically in the context of the damped Korteweg-de Vries （KdV） equation and the damped Benjamin-Bona-Mahony （BBM） equation. In this paper we intend to show the same results hold for the pure KdV equation （without the damping terms） posed on a finite domain. Consideration is given to the initial-boundary-value problem {ut＋ux＋uux＋uxxx=0, u（x,0）=φ（x）, 0〈x〈1, t〉0,u（0,t）=h（t）, u（1,t） = 0, ux（1,t） = 0, t〉*** is shown that if the boundary forcing h is periodic with small ampitude, then the small amplitude solution u of （＊） becomes eventually time-periodic. Viewing （＊）（without the initial condition） as an infinite-dimensional dynamical system in the Hilbert space L^2（0, 1）, we also demonstrate that for a given periodic boundary forcing with small amplitude, the system （＊） admits a （locally） unique limit cycle, or forced oscillation, which is locally exponentially stable. A list of open problems are included for the interested readers to conduct further investigations.

关键词： Forced oscillation stability the BBM equation the KdV equation time-periodic solution

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Medicinal plants against hepatitis C virus

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World Journal of Gastroenterology 2014年第11期20卷 2941-2947页

作者： usman A Ashfaq Sobia Idrees Department of Bioinformatics and Biotechnology Government College UniversityFaisalabad 38000Pakistan

Hepatitis C virus (HCV) is a global health concern which is responsible for most of the liver diseases. Currently, there is no vaccine available for prevention of HCV infection due to the high degree of strain variation. The current standard of care is a combination of pegylated interferon α with ribavirin and boceprevir/telaprevir. This treatment was partially effective and had significant side effects. Hence, there is a need to develop new antiviral agents that interfere with different stages of the HCV life cycle. Recent advances in the understanding of both the cellular and molecular mechanisms of HCV replication have provided the basis for novel therapeutic strategies. Several hundred plant species and their phyto-constituents have been isolated for screening against HCV, and some have been shown to have great medicinal value in preventing and/or ameliorating viral diseases in pre-clinical and clinical trials. This review summarizes medicinal plants and their phytochemicals which inhibit different stages of HCV life cycle and discuss their potential use in HCV therapy.

关键词： Hepatitis C virus Medicinal plants Anti-hepatitis C virus drugs

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Prediction of Extremist Behaviour and Suicide Bombing from Terrorism Contents Using Supervised Learning

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Computers, Materials & Continua 2022年第3期70卷 4411-4428页

作者： Nasir Mahmood Muhammad usman Ghani Khan Department of Computer Science University of Engineering and Technology54890Lahore

This study proposes an architecture for the prediction of extremist human behaviour from projected suicide *** linking‘dots’of police data comprising scattered information of people,groups,logistics,locations,communication,and spatiotemporal characters on different social media groups,the proposed architecture will spawn beneficial *** useful information will,in turn,help the police both in predicting potential terrorist events and in investigating previous ***,this architecture will aid in the identification of criminals and their associates and *** is psychological warfare,which,in the broadest sense,can be defined as the utilisation of deliberate violence for economic,political or religious *** this study,a supervised learning-based approach was adopted to develop the proposed *** dataset was prepared from the suicide bomb blast data of Pakistan obtained from the South Asia Terrorism Portal(SATP).As the proposed architecture was simulated,the supervised learning-based classifiers na飗e Bayes and Hoeffding Tree reached 72.17%*** of the additional benefits this study offers is the ability to predict the target audience of potential suicide bomb blasts,which may be used to eliminate future threats or,at least,minimise the number of casualties and other property losses.

关键词： Extremism terrorism suicide bombing crime prediction pattern recognition machine learning supervised learning

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The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 2025-2036页

作者： Jamilu usman Abdul Waheed Umair Baig Isam HAljundi Interdisciplinary Research Centre for Membranes and Water Security King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Chemical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical *** this study,we designed and fabricated three novel membranes with different active layers using the crosslinkers:terephthaloyl chloride,isophthaloyl chloride,and trimesoyl *** crosslinkers were reacted with an aqueous solution of an aliphatic *** these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization,the resultant membranes also possess different structural *** water contact angle of the fabricated membranes also varies;the water contact angles of 4A-3P-TPC@PSF/PET,4A-3P-TMC@PSF/PET,and 4A-3P-IPC@PSF/PET,are 68.9°,65.6°,and 53.9°,***,the desalination performance of resultant membranes also showed variations,with 4A-3P-TPC@PSF/PET,4A-3P-IPC@PSF/PET,and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14,25.70,and 30.90 L·m^(−2)·h^(−1),respectively,at 2.5 *** 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine,and cationic dye rhodamine B,MgCl_(2),and amitriptyline rejection rates of 98.6%,92.7%and 80.9%,*** 4A-3P-TMC@PSF/PET membrane showed mediocre performance,while 4A-3P-IPC@PSF/PET membrane showed even lower performance,with a 35%rejection of methyl orange dye.

关键词： acid chlorides covalent crosslinking desalination linear aliphatic amine micropollutant removal thin film composite membranes

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HybridHR-Net:Action Recognition in Video Sequences Using Optimal Deep Learning Fusion Assisted Framework

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Computers, Materials & Continua 2023年第9期76卷 3275-3295页

作者： Muhammad Naeem Akbar Seemab Khan Muhammad Umar Farooq Majed Alhaisoni usman Tariq Muhammad usman Akram Department of Computer Engineering National University of Sciences and Technology(NUST)Islamabad46000Pakistan Department of Robotics SMME NUSTIslamabad45600Pakistan Computer Sciences Department College of Computer and Information SciencesPrincess Nourah Bint Abdulrahman UniversityRiyadh11671Saudi Arabia Management Information System Department College of Business AdministrationPrince Sattam bin Abdulaziz UniversityAl-Kharj16278Saudi Arabia

The combination of spatiotemporal videos and essential features can improve the performance of human action recognition(HAR);however,the individual type of features usually degrades the performance due to similar actions and complex *** deep convolutional neural network has improved performance in recent years for several computer vision applications due to its spatial *** article proposes a new framework called for video surveillance human action recognition dubbed *** a few selected datasets,deep transfer learning is used to pre-trained the EfficientNet-b0 deep learning *** optimization is employed for the tuning of hyperparameters of the fine-tuned deep *** of fully connected layer features,we considered the average pooling layer features and performed two feature selection techniques-an improved artificial bee colony and an entropy-based *** a serial nature technique,the features that were selected are combined into a single vector,and then the results are categorized by machine learning *** publically accessible datasets have been utilized for the experimental approach and obtained notable accuracy of 97%,98.7%,100%,99.7%,and 96.8%,***,a comparison of the proposed framework with contemporarymethods is done to demonstrate the increase in accuracy.

关键词： Action recognition entropy deep learning transfer learning artificial bee colony feature fusion

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Highly selective and stable hydrogenation of heavy aromatic-naphthalene over transition metal phosphides

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Science China Chemistry 2015年第4期58卷 738-746页

作者： Muhammad usman Dan Li Chunshan Li Suojiang Zhang Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex SystemsInstitute of Process Engineering University of Chinese Academy of Sciences

The present study reports a highly selective and stable catalytic approach for producing tetralin, an important chemical, solvent, and H2 storage material. Transition metal phosphides （MOP, Ni2P, Co2P, and Fe2P） were prepared by wet impregnation and temperature-programmed reduction and characterized by X-ray diffraction （XRD）, energy dispersive X-ray spectroscopy （EDX）, EDX mapping, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, brunauer-emmett- teller （BET）, temperature-programmed desorption of ammonia （NH3-TPD）, and fourier transform infrared spectroscopy of pyridine （pyridine-FTIR）. Of all the transition metal phosphides MoP was formed at a lower reduction temperature, which resuited in smaller particle size that enhanced the overall surface area of the catalyst. The existence of weak, moderate, and Lewis acidic sites over MoP were responsible for its high tetralin selectivity （90%） and stability during the 100 h reaction on-stream in a fixed-bed reactor.

关键词： coal tar naphthalene transition metal phosphides selective hydrogenation tetralin

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Natural convection of CuO–water nanofluid filled in a partially heated corrugated cavity:KKL model approach

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Communications in Theoretical Physics 2020年第8期72卷 27-42页

作者： Rizwan Ul Haq Muhammad usman Ebrahem A Algehyne Department of Electrical Engineering Bahria UniversityIslamabadPakistan BIC-ESAT College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Department of Mathematics Faculty of SciencesUniversity of TabukP.O.Box 741Tabuk 71491Saudi Arabia

In this article, flow and heat transfer inside a corrugated cavity is analyzed for natural convection with a heated inner obstacle. Thermal performance is analyzed for Cu O–water inside a partially heated domain by defining the constraint along the boundaries. For nanofluid analysis, the Koo and Kleinstreuer Li(KKL) model is implemented to deal with the effective thermal conductivity and viscosity. A heated thin rod is placed inside the corrugated cavity and the bottom portion of the corrugated cavity is partially heated. The dimensionless form of nonlinear partial differential equations are obtained through the compatible transformation along with the boundary constraint. The finite element method is executed to acquire the numerical solution of the obtained dimensional system. Streamlines, isotherms and heat transfers are analyzed for the flow field and temperature distribution. The Nusselt number is calculated at the surface of the partially heated domain for various numerical values of emerging parameters by considering the inner obstacle at cold, adiabatic and heated conditions. The computational simulation was performed by introducing various numerical values of emerging parameters. Important and significant results have been attained for temperature and velocities(in both x-and y-directions) at the vertically and horizontally mean positions of the corrugated duct.

关键词： heat transfer nanofluid finite element method KKL corrugated cavity

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