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Suppression of methane formation during Fisher-Tropsch synthesis using manganese-cobalt oxide supported on H-5A zeolite as a catalyst

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Journal of Natural Gas Chemistry 2009年第2期18卷 187-190页

作者： Syed Tajammul Hussain muhammad Mazhar muhammad arif Nadeem National Centre for Physics Quaid-i-Azam UniversityIslamabad 43520 Pakistan Department of Chemistry Quaid-i-Azam UniversityIslamabad 43520 Pakistan

In Fischer-Tropsch synthesis reaction, methane formation is one of the side reactions which must be suppressed in order to get better catalytic selectivity for light olefins. In the present study, we have modified cobalt based Fischer-Tropsch catalyst and developed a process to minimize methane production, consequently to produce maximum yield of light olefins. Manganese-cobalt oxide supported on H-5A zeolite catalyst was synthesized using modified H-5A zeolite, to increase its surface acid sites. Increased acidity of zeolite plays a major part in the suppression of methane formation during the Fischer-Tropsch reaction. The modified zeolite results in the electronic modification of catalyst surface by creating new active catalytic sites. The results are compared with other supported catalysts along with unmodified zeolite. Appreciable reduction in methane formation is achieved on modified zeolite supported catalyst in comparison with unsupported catalyst.

关键词： methane formation Fisher-Tropsch synthesis manganese cobalt suppression

Classification of Human Protein in Multiple Cells Microscopy Images Using CNN

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Computers, Materials & Continua 2023年第8期76卷 1763-1780页

作者： Lina Al-joudi muhammad arif Department of Computer Science AI(CS-AI) Umm Al Qura University(UQU)Makkah24231Saudi Arabia

The subcellular localization of human proteins is vital for understanding the structure of human *** play a significant role within human cells,as many different groups of proteins are located in a specific location to perform a particular *** these functions will help in discoveringmany diseases and developing their *** importance of imaging analysis techniques,specifically in proteomics research,is becoming more *** recent advances in deep learning techniques for analyzing microscopy images,classification models have faced critical challenges in achieving high *** protein subcellular images have a significant class *** use oversampling and under sampling techniques in this research to overcome this *** have used a Convolutional Neural Network(CNN)model called GapNet-PL for the multi-label classification task on the Human Protein Atlas Classification(HPA)*** have found that the ParametricRectified LinearUnit(PreLU)activation function is better than the Scaled Exponential LinearUnit(SeLU)activation function in the GapNet-PL model in most classification *** results showed that the GapNet-PL model with the PReLU activation function achieved an area under the ROC curve(AUC)equal to 0.896,an F1 score of 0.541,and a recall of 0.473.

关键词： CNN protein PReLU SeLU microscopy images subcellular localization multi-cells

A reliable numerical analysis for stochastic gonorrhea epidemic model with treatment effect

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International Journal of Biomathematics 2019年第6期12卷 221-246页

作者： Ali Raza muhammad Shoaib arif muhammad Ualiq Department of Mathematics Stochastic Analysis and Optimization Research Group Air University PAF Complex E-9 Islamabad 44000PedralPakistan Faculty of Engineering.University of Central PunjabLahore 54000 PunjabPakistan

The phenomena of disease spread are unpredictable in nature due to random mixing of individuals in a *** is of more significance to include this randomness while modeling infectious *** epidemics including tlieir stochastic behavior could be a more realistic approach in many *** thus paper,a stochastic gon orrhea epidemic model with treatment effect has been analyzed *** solution of stochastic model is presented in comparison with its deterministic *** dynamics of the gonorrhea disease is governed by a threshold quantity Ai called basic reproductive ***.A11 shows the persistence of disease in *** standard numerical schemes like Euler *** Euler and stochastic Rurige Kutta are highly dependent on step size and do not behave well in certain scenarios.A competitive non-standard finite dif ference numerical scheme in stochastic setting is proposed,which is independent of step size and remains consistent with the corresponding deterministic model.

关键词： Gonorrhea disease stochastic differential equations stochastic numerical schemes

A Hybrid SIR-Fuzzy Model for Epidemic Dynamics:A Numerical Study

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3417-3434页

作者： muhammad Shoaib arif Kamaleldin Abodayeh Yasir Nawaz Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Mathematics Air UniversityIslamabad44000Pakistan

This study focuses on the urgent requirement for improved accuracy in diseasemodeling by introducing a newcomputational framework called the Hybrid SIR-Fuzzy *** integrating the traditional Susceptible-Infectious-Recovered(SIR)modelwith fuzzy logic,ourmethod effectively addresses the complex nature of epidemic dynamics by accurately accounting for uncertainties and imprecisions in both data and model *** main aim of this research is to provide a model for disease transmission using fuzzy theory,which can successfully address uncertainty in mathematical *** main emphasis is on the imprecise transmission rate parameter,utilizing a three-part description of its membership *** enhances the representation of disease processes with greater complexity and tackles the difficulties related to quantifying uncertainty in mathematical *** investigate equilibrium points for three separate scenarios and perform a comprehensive sensitivity analysis,providing insight into the complex correlation betweenmodel parameters and epidemic *** order to facilitate a quantitative analysis of the fuzzy model,we propose the implementation of a resilient numerical *** convergence study of the scheme demonstrates its trustworthiness,providing a conditionally positive solution,which represents a significant improvement compared to current forward Euler *** numerical findings demonstrate themodel’s effectiveness in accurately representing the dynamics of disease ***,when the mortality coefficient rises,both the susceptible and infected populations decrease,highlighting the model’s sensitivity to important epidemiological ***,there is a direct relationship between higher Holling type rate values and a decrease in the number of individuals who are infected,as well as an increase in the number of susceptible *** correlation offers a significant understanding of how many elements affect the con

关键词： Fuzzy-based model sensitivity equilibriumpoints proposed numerical scheme convergence and stability analysis

Computational Modeling of Reaction-Diffusion COVID-19 Model Having Isolated Compartment

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1719-1743页

作者： muhammad Shoaib arif Kamaleldin Abodayeh Asad Ejaz Department of Mathematics and Sciences College of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia Department of Mathematics Air UniversityPAF Complex E-9Islamabad44000Pakistan

Cases of COVID-19 and its variant omicron are raised all across the *** most lethal form and effect of COVID-19 are the omicron version,which has been reported in tens of thousands of cases daily in numerous *** WHO(World health organization)records on 30 December 2021,the cases of COVID-19 were found to be maximum for which boarding individuals were found 1,524,266,active,recovered,and discharge were found to be 82,402 and 34,258,778,*** there were 160,989 active cases,33,614,434 cured cases,456,386 total deaths,and 605,885,769 total samples *** far,1,438,322,742 individuals have been *** coronavirus or COVID-19 is inciting panic for several *** is a new virus that has affected the whole *** have introduced certain ways to prevent the *** can lower the danger of infection by reducing the contact rate with other *** crowded places and social events withmany people reduces the chance of one being exposed to the *** deadly COVID-19 spreads *** is thought that the upcoming waves of this pandemicwill be evenmore *** have presented severalmathematical models to study the pandemic and predict future *** need of the hour is to restrict the mobility to control the infection from ***,separating affected individuals from healthy people is essential to control the *** consider the COVID-19 model in which the population is divided into five *** present model presents the population’s diffusion effects on all susceptible,exposed,infected,isolated,and recovered *** reproductive number,which has a key role in the infectious models,is *** equilibrium points and their stability is *** numerical simulations,finite difference(FD)schemes like nonstandard finite difference(NSFD),forward in time central in space(FTCS),and Crank Nicolson(CN)schemes are *** core characteristics

关键词： Reproductive number stability Routh Hurwitz criterion variational matrix NSFD scheme FTCS scheme Crank Nicolson scheme consistency

Advancements in Numerical Solutions:Fractal Runge-Kutta Approach to Model Time-Dependent MHD Newtonian Fluid with Rescaled Viscosity on Riga Plate

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Computer Modeling in Engineering & Sciences 2024年第11期141卷 1213-1241页

Fractal time-dependent issues in fluid dynamics provide a distinct difficulty in numerical analysis due to their complex characteristics,necessitating specialized computing techniques for precise and economical *** study presents an innovative computational approach to tackle these *** main focus is applying the Fractal Runge-Kutta Method to model the time-dependent magnetohydrodynamic(MHD)Newtonian fluid with rescaled viscosity flow on Riga *** efficient computational scheme is proposed for handling fractal time-dependent problems in flow *** scheme is comprised of three stages and constructed using three different time *** stability of the scheme is shown by employing the Fourier series analysis to solve scalar *** scheme’s convergence is guaranteed for a time fractal partial differential equations *** scheme is applied to the dimensionless fractal heat and mass transfer model of incompressible,unsteady,laminar,Newtonian fluid with rescaled viscosity flow over the flat and oscillatory Riga plates under the effects of space-and temperature-dependent heat *** first-order back differences discretize the continuity *** results show that skin friction local Nusselt number declines by raising the coefficient of the temperature-dependent term of heat source and Eckert *** numerical simulations provide valuable insights into fluid dynamics,explicitly highlighting the influence of the temperature-dependent coefficient of the heat source and the Eckert number on skin friction and local Nusselt number.

关键词： Fractal scheme stability convergence fractal Newtonian fluid with rescaled viscosity fluid heat generation

Structure of [Co(im)6]SiF6：Short Hydrogen Bonds Involving SiF62- Ions

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Chinese Journal of Structural Chemistry 2017年第6期36卷 965-970页

作者： NAZIR Sadia arif muhammad RASHID muhammad Abid WHITWOOD Adrian Charles Department of Chemistry Govt. College Women University Faisalabad 3800 Pakistan Institute of Chemical Sciences Bahhauddin Zakariya University Multan 60800 Pakistan Department of Chemistry University of Agriculture Faisalabad 38040 Pakistan Department of Chemistry University of York Heslington York YO10 5DD UK

A new complex C（18）H（24）CoF6N（12）Si has been synthesized by the reaction of cobalt（II） fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. This complex has been characterized by different techniques such as elemental analysis, IR studies, magnetic measurements, electronic absorption measurements and single-crystal X-ray structure determination. The crystals are hexagonal in the R-3 space group, with a = 13.225（6）, b = 13.225（6）, c = 12.517（11） A, and g = 120°. In complex [Co（im）6]SiF6, the cobalt atom is six-coordinated to adopt a regular octahedral geometry and the SiF62-ion acts as the counter anion. The crystal displays a network structure and SiF62- bridging hexagram formation by N-（39）···F-Si interactions between imdazole and SiF62-. SiF62-plays an important role in assembling the supramolecular aggregates.

关键词： anion binding imidazole SiF62- hydrogen bonds transitionmetal fluoride complexes

Solution of Algebraic Lyapunov Equation on Positive-Definite Hermitian Matrices by Using Extended Hamiltonian Algorithm

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Computers, Materials & Continua 2018年第2期54卷 181-195页

作者： muhammad Shoaib arif Mairaj Bibi Adnan Jhangir Department of Mathematics Air UniversityPAF ComplexE-9IslamabadPakistan Department of Mathematics Comsats Institute of Information TechnologyPark RoadChak-ShahzadIslamabadPakistan Department of Mathematics Comsats Institute of Information TechnologyWah CanttPakistan

This communique is opted to study the approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian *** choose the geodesic distance between􀀀AHX􀀀XA and P as the cost function,and put forward the Extended Hamiltonian algorithm(EHA)and Natural gradient algorithm(NGA)for the ***,several numerical experiments give you an idea about the effectiveness of the proposed *** also show the comparison between these two algorithms EHA and *** results are provided and analyzed *** also conclude that the extended Hamiltonian algorithm has better convergence speed than the natural gradient algorithm,whereas the trajectory of the solution matrix is optimal in case of Natural gradient algorithm(NGA)as compared to Extended Hamiltonian Algorithm(EHA).The aim of this paper is to show that the Extended Hamiltonian algorithm(EHA)has superior convergence properties as compared to Natural gradient algorithm(NGA).Upto the best of author’s knowledge,no approximate solution of the Algebraic Lyapunov equation on the manifold of positive-definite Hermitian matrices is found so far in the literature.

关键词： Information geometry algebraic lyapunov equation positive-definite hermitianmatrix manifold natural gradient algorithm extended hamiltonian algorithm

Highly active sites of NiVB nanoparticles dispersed onto graphene nanosheets towards efficient and pH-universal overall water splitting

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Journal of Energy Chemistry 2021年第7期30卷 237-246页

作者： muhammad arif Ghulam Yasin muhammad Shakeel muhammad Asim Mushtaq Wen Ye Xiaoyu Fang Shengfu Ji Dongpeng Yan Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001HenanChina

Production of hydrogen(H2) and oxygen(O2) through electrocatalytic water splitting is one of the sustainable,green and pivotal ways to accomplish the ever-increasing demands for renewable energy sources,but remains a big challenge because of the uphill reaction during overall water ***,we develop high-performance non-noble metal electrocatalysts for pH-universal water splitting,based on nickel/vanadium boride(NiVB) nanoparticles/reduced graphene oxide(rGO) hybrid(NiVB/rGO)through a facile chemical reduction approach under ambient *** virtue of more exposure to surface active sites,superior electron transfer capability and strong electronic coupling,the asprepared NiVB/rGO heterostructure needs pretty low overpotentials of 267 and 151 mV to deliver a current density of 10 mA cm^(-2) for oxygen evolution reaction(OER) and hydrogen evolution reaction(HER)respectively,with the corresponding Tafel slope of 44 and 88 mV dec^(-1) in 1.0 M ***,the NiVB/rGO electrocatalysts display a promising performance in a wide-pH conditions that require low overpotential of 310,353 and 489 mV to drive a current density of 10 mA cm^(-2) for OER under 0.5 M KOH,0.05 M H2SO4 and 1.0 M phosphate buffer solution(PBS) respectively,confirming the excellent electrocata lytic performance among state-of-the-art Ni-based electrocatalysts for overall water ***,the interfacial tuning based on incorporation of active heterostructure may pave a new route to develop bifunctional,cost-effective and efficient electrocatalyst systems for water splitting and H2 production.

关键词： Electrocatalysis Oxygen evolution reaction Hydrogen evolution reaction NiVB/rGO heterostructure pH-universal