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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.mUHAmmAD m.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in mATHEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： convective boundary condition Darcy-Forchheimer medium hybrid nanofluid Joule heating magnetohydrodynamic (mHD) numerical solution squeezing flow regression analysis O361 O175.2

Feasibility of new ladle-treated Hadfield steel for mining purposes

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International Journal of minerals,metallurgy and materials 2018年第3期25卷 300-309页

作者： m.k. El Fawkhry Central metallurgical Research and Development Institute (CmRDI) Box 87 Helwan Egypt

A debate has arisen over the possibility of using a new ladle-treated Hadfield steel instead of conventional heat-treated Hadfield steel in mining applications. This debate might be solved by identifying the differences between the mechanical properties and strain-hardening properties of conventional heat-treated Hadfield steel and its counterpart ladle-treated Hadfield steel. Tensile and compression tests demonstrated that the ductility of ladle-treated Hadfield steel is similar to that of conventional heat-treated steel. However, the strain-hardening property of the ladle-treated Hadfield steel is almost two times higher than that of the heat-treated Hadfield steel. The results of this study demonstrate that the improvement of the strain-hardening behavior is attributable to the low stacking-fault energy of the main austenite matrix, which results from the high segregation coefficient of carbon and manganese solutes of the main austenite matrix into the new eutectic phase. Superior wear abrasion resistance is a potential consequence of different strain-hardening properties under low and high loads.

关键词： Hadfield steel ladle treatment process wear abrasion resistance strain hardening properties mechanical properties

methanol conversion to DmE as a blue fuel：The beneficial use of ultrasonic irradiation for the preparation of CuO/H-mOR nanocatalyst

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燃料化学学报 2014年第11期42卷 1340-1350页

作者： Sameh m.k. Aboul-Fotouh Ain Shams University Faculty of Education Chemistry Department Roxy Cairo 11566 Egypt

methanol conversion to DmE was investigated over CuO /H-mOR nanocatalyst prepared by precipitation and /or by precipitation flowed by ultrasonic irradiation methods. BET,XRD,SEm,NH3-TPD and H2-TPR techniques were used to characterize nanocatalysts. The effective ultrasonication factors encountered during carrying out the dehydration of methanol on Cuo /H-mOR zeolite catalysts to produce dimethylether are studied in the present work. These factors include: the type of ultrasonication media,the ultrasonication time,and the fixed weight of the solid catalyst per the volume of the ultrasonication liquid media( Wcatalyst/ Vliquidratio). XRD showed that structure of H-mOR is not damaged even after it is loaded with CuO nanoparticles or with ultrasonication. H2-TPR profiles indicated that reducibility of sonicated CuO / H-mOR nanocatalyst is higher than non-sonicated catalyst. It is found that employing ultrasound energy for 60 min has the highest influence on the surface properties of nanocatalyst and its catalytic performance( activity and stability) of CuO / H-mOR catalyst. Surface morphology( SEm) of the sonicated CuO /H-mOR catalysts have clarified that methanol by itself used as an ultrasonication medium gives the best results concerning the homogeneity of particle sizes compared to the non-sonicated catalyst,where large agglomerates and non-homogeneous clusters appeared. Water used as a sonication medium showed many large agglomerates in addition to some smaller particles resulted in lowcatalytic activity. The different alcohols and( Wcatalyst/ Vliquid) ratio were examined to give precise correlation with the catalytic activity of the sonicated CuO / H-mOR zeolite catalyst. These findings certified that ultrasonication has a deep effect on the surface morphology and hence on the catalytic behavior of the dehydration of methanol to DmE. NH3-TPD shows that ultrasound irradiation has enhanced the acidity of CuO / H-mOR catalyst and hence it's catalytic performance for

关键词：燃料化学催化原理催化反应

Effect of (Ba_(0.6)Sr_(0.4))TiO_3(BST) Doping on Dielectric Properties of CaCu_3Ti_4O_(12)(CCTO)

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Journal of materials Science & Technology 2012年第12期28卷 1137-1144页

作者： I. Norezan A.k. Yahya m.k. Talari Faculty of Applied Sciences Universiti Teknologi MARAShah Alam Selangor Malaysia

The effect of （Ba（0.6）Sr（0.4））TiO3（BST） addition on dielectric properties of CaCu3Ti4O（12）（CCTO） ceramic was investigated. Ceramic samples with the chemical formula （1-x）CaCu3Ti4O（12）＋ x（Ba（0.6）,Sr（0.4））TiO3 （x=0, 0.05, 0.1, and 0.2） were synthesized from high purity oxide powders by the conventional solid-state synthesis method. X-ray diffraction （XRD） analysis showed the existence of BST as a secondary phase alongside CCTO. Scanning electron microscopy （SEm） investigation showed a slight decrease in grain size of doped CCTO samples. Density measurements showed that porosity content increased with increasing BST addition indicating low densification due to high melting point secondary phase addition. Dielectric constant of undoped CCTO （x=0） showed lack of stability with frequency which dropped drastically between 104 and 105Hz and accompanied by high dielectric loss. Addition of BST into CCTO caused the dielectric constant to slightly decrease but improved stability with frequency compared to the undoped sample. The decrease in dielectric constant of doped CCTO samples was suggested to be partly due to the decrease in average grain size and increase in porosity with BST addition. Nevertheless, a high value of dielectric constant was still maintained around ～104 range for all doped samples. The dielectric loss （tanδ） of all BST-doped samples was lower than that of pure CCTO sample at the frequency range of 103 to 105 Hz probably due to the increase of grains boundary resistivity. The activation energy of grains boundary （E（gb）） showed higher values as compared to the activation energy of grains （Eg ） for all samples and conforms to the internal barrier layer capacitor （IBLC） model.

关键词： CaCu3Ti4O(12)(CCTO) Dielectric properties (Ba(0.6)Sr(0.4))TiO3(BST)

Failure pattern in ceramic metallic target under ballistic impact

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Defence Technology（防务技术） 2024年第10期40卷 173-190页

作者： m.A.Iqbal m.k.khan Department of Civil Engineering Indian Institute of Technology RoorkeeRoorkee 247667India Department of Civil Engineering Aligarh Muslim UniversityAligarh202002India

The ballistic resistance and failure pattern of a bi-layer alumina 99.5%-aluminium alloy 1100-H12 target against steel 4340 ogival nosed projectile has been explored in the present experimental cum numerical *** the experimental investigation,damage induced in the ceramic layer has been quantified in terms of number of cracks developed and failure zone *** resultant damage in the backing layer has been studied with variation in the bulge and perforation hole in the backing layer with the varying incidence *** discussion of the experimental results has been further followed by three dimensional finite element computations using ABAQUS/Explicit finite code to investigate the behaviour of different types of bi-layer targets under multi-hit projectile *** JH-2 constitutive model has been used to reproduce the behaviour of alumina 99.5%and JC constitutive model has been used for steel 4340 and aluminium alloy *** total energy dissipation has been noted to be of lesser magnitude in case of sub-sequential impact in comparison to simultaneous impact of two *** distance between the impact points of two projectiles also effected the ballistic resistance of bi-layer *** ballistic resistance of single tile ceramic front layer and four tile ceramic of equivalent area found to be dependent upon the boundary conditions provided to the target.

关键词： Ballistic resistance Bi-layer target Ceramic metal armour multi-hit impact Finite element modelling

Non-maximal Tripartite Entanglement Degradation of Dirac and Scalar Fields in Non-Inertial Frames

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Communications in Theoretical Physics 2014年第3期61卷 281-288页

作者： Salman khan Niaz Ali khan m.k.khan Department of Physics COMSATS Institute of Information Technology Chak Shahzad Department of Physics Quaid-i-Azam University

The π-tangle is used to study the behavior of entanglement of a nonmaximal tripartite state of both Dirac and scmar fields in accelerated frame. For Dirac fields, the degree of degradation with acceleration of both one-tangle of accelerated observer and π-tangle, for the same initial entanglement, is different by just interchanging the values of probability amplitudes. A fraction of both one-tangles and the π-tangle always survives for any choice of acceleration and the degree of initial entanglement. For scalar field, the one-tangle of accelerated observer depends on the choice of values of probability amplitudes and it vanishes in the range of infinite acceleration, whereas for 1r-tangle this is not always true. The dependence of π-tangle on probability amplitudes varies with acceleration. In the lower range of acceleration, its behavior changes by switching between the values of probability amplitudes and for larger values of acceleration this dependence on probability amplitudes vanishes. Interestingly, unlike bipartite entanglement, the degradation of π-tangle against acceleration in the case of sca/ar fields is slower than for Dirac fields.

关键词： tripartite entanglement noninertial frame

Quantum model of Bertrand Duopoly

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Chinese Physics Letters 2010年第8期27卷 11-14页

作者： Salman khan m. Ramzan m. k. khan Department of Physics Quaid-i-Azam University lslamabad 45320 Pakistan

We present a quantum model of Bertrand duopoly and study the entanglement behavior on the profit functions of the firms. Using the concept of optimal response of each firm to the price of the opponent, we find only one Nash equilibirum point for the maximally entangled initial state. The presence of quantum entanglement in the initial state gives payoffs higher to the firms than the classical payoffs at the Nash equilibrium. As a result, the dilemma-like situation in the classical game is resolved.

关键词： QUANTUm theory PROFIT & loss PRICES NASH equilibrium ECONOPHYSICS

Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： S U khan m.k.A Rahim Advanced RF & microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（mPT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of Hankel matrix（Hm） and execute the singular value decomposition（SVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of Hm. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

Quantum monty Hall Problem under Decoherence

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Communications in Theoretical Physics 2010年第7期54卷 47-54页

作者： Salman khan m.Ramzan m.k.khan Department of Physics Quaid-i-Azam University

We study the effect of decoherence on quantum monty Hall problem under the influence of amplitude damping, depolarizing, and dephasing channels. It is shown that under the effect of decoherence, there is a Nash equilibrium of the game in case of depolarizing channel for Alice＇s quantum strategy. Whereas in case of dephasing noise, the game is not influenced by the quantum channel. For amplitude damping channel, Bob＇s payoffs are found symmetrical about a decoherence of 50% and the maximum occurs at this value of decoherence for his classical strategy. However, it is worth-mentioning that in case of depolarizing channel, Bob＇s classical strategy remains always dominant against any choice of Alice＇s strategy.

关键词： quantum monty Hall problem decoherence entanglement payoffs