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Strong interfacial charge transfer between hausmannite manganese oxide and alumina for efficient photocatalysis

Chinese Journal of Chemical Engineering 2021年第5期34卷 147-159页

作者： Aisha Kanwal Shamaila Sajjad Sajjad Ahmed khan Leghari Muhammad Naeem khan International Islamic University H-10 IslamabadPakistan Pakistan Institute of Engineering and Applied Sciences Islamabad 44000Pakistan Department of Chemistry Government College of ScienceLahorePakistan

Well crystalline manganese oxide(Mn_(3)O_(4))nanoparticles anchored on gamma alumina(γ-Al_(2)O_(3))have been successfully tailored via a proficient and cost effective chemical process as an efficient material for photo *** indicated the composite formation ofγ-Al_(2)O_(3) and hausmannite structure of Mn_(3)O_(4).SEM and TEM revealed that hetero structure of Mn_(3)O_(4)/γ-Al_(2)O_(3) exhibits an amalgam of aggregated nanoparticles and *** demonstrated the chemical states of binary *** band gap tuning has been performed withγ-Al_(2)O_(3) nanoparticles by assimilating hausmannite Mn_(3)O_(4) particles into flower like microstructure of Al_(2)O_(3).The photoluminescence spectra affirmed the enhancement in charge separation in Mn_(3)O_(4)/γ-Al_(2)O_(3) binary hybrid *** band gap becomes narrow with the increase in concentrations of Mn_(3)O_(4).The narrowing of band gap is concorded with crystalline domains of primary aggregated *** elucidate the mechanism of the photocatalytic activity linear sweep voltammetry was *** results showed that Mn_(3)O_(4)/γ-Al_(2)O_(3) nanocomposite revealed the enhancement in current density as compared to pureγ-Al_(2)O_(3) which confirmed the electron transfer from Mn_(3)O_(4) toγ-Al_(2)O_(3) through the interfacial potential gradient in conduction *** optimum concentration of 6.0%Mn_(3)O_(4)/γ-Al_(2)O_(3) for hybrid structure showed an excellent photocatalytic activity under visible light due to narrow band gap *** degree distribution of Mn_(3)O_(4) nano architects overlying onγ-Al_(2)O_(3) induces a significant synergic effect betweenγ-Al_(2)O_(3) and hausmannite phase of manganese oxide(Mn_(3)O_(4)).This strong interfacial contact betweenγ-Al_(2)O_(3) and Mn_(3)O_(4) endures the quick transfer of photo generated charge carriers across interface.

关键词： Hausmannite Mn_(3)O_(4) Alumina Band gap tuning Interfacial charge transfer Nanomaterials Catalysis

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Time stepping in discontinuous Galerkin method

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Journal of Hydrodynamics 2013年第3期25卷 321-329页

作者： LAI Wencong khan Abdul A Glenn Department of Civil Engineering Clemson University Clemson S.C. USA

The time discretization in the Discontinuous Galerkin （DG） scheme has been traditionally based on the Total Variation Diminishing （TVD） second-order Runge-Kutta （RK2） scheme. Computational efficiency and accuracy with the Euler Forward （EF） and the TVD second-order RK2 time stepping schemes in the DG method are investigated in this work. Numerical tests are condu- cted with the scalar Burgers equation, 1-D and 2-D shallow water flow equations. The maximum Courant number or time step size required for stability for the EF scheme and RK2 scheme with different slope limiters are compared. Numerical results show that the slope limiters affect the stability requirement in the DG method. The RK2 scheme is generally more diffusive than the EF scheme, and the RK2 scheme allows larger time step sizes. The EF scheme is found to be more efficient and accurate than the RK2 scheme in the DG method in computation.

关键词： Discontinuous Galerkin (DG) method Euler Forward (EF) scheme second-order Runge-Kutta scheme

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A Seismic Hazard Map Based on Geology and Shear-wave Velocity in Rawalpindi–Islamabad,Pakistan

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 659-673页

作者： Sarfraz khan Muhammad WASEEM M.Asif khan National Centre of Excellence in Geology University of Peshawar 25130KPPakistan University of Peshawar 25120 KPPakistan

The‘twin cities’district of Rawalpindi–Islamabad is among the most endangered seismic regions in Pakistan,with the seismic hazard assessed(0.32 g)to intensity IX MMI for a 475-year return period.A seismic hazard map for Rawalpindi–Islamabad is presented herein,based on 85 shear-wave velocity(VS)profiles obtained through geophysical H/V measurements and from the geological map of the *** between the average top thirty-meter shear-wave velocities(VS30)and surficial geological units have been *** peak ground acceleration(PGA)maps for 150,475 and 2475-year return periods were converted into a seismic intensity *** increments for different soils were used to compute PGA values for 150,475 and 2475-year return *** located on softer ground experienced a higher degree of damage from moderate *** to the presence of soft clay or liquefiable soil and lateral spreading,a few locations may be classified as hybrid sites class C and *** map is a critical step in facilitating code-based site classification and seismic design throughout Rawalpindi–*** the seismic hazard map based on seismic intensities is no longer used in engineering geology,it is still important in seismological analysis and for civil protection purposes.

关键词： seismic hazard site classification intensity increment engineering geology Rawalpindi-Islamabad

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A novel fractional case study of nonlinear dynamics via analytical approach

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 276-290页

作者： Hassan khan Adnan khan Rasool Shah Dumitru Baleanu Department of Mathematics Abdul Wali khan UniversityMardan 23200Pakistan Department of Mathematics Faculty of Arts and SciencesCankaya UniversityAnkara 06530Turkey Institute of Space Sciences Magurele-BucharestRomania

The present work describes the fractional view analysis of Newell-Whitehead-Segal equations,using an innovative *** work is carried with the help of the Caputo operator of fractional *** analytical solutions of some numerical examples are presented to confirm the reliability of the proposed *** derived results are very consistent with the actual solutions to the problems.A graphical representation has been done for the solution of the problems at various fractional-order ***,the solution in series form has the desired rate of convergence and provides the closed-form *** is noted that the procedure can be modified in other directions for fractional order problems.

关键词： Homotopy Perturbation method Shehu transform Newell-Whitehead-Segel Equation Caputo operator

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Improvement of mobility edge model by using new density of states with exponential tail for organic diode

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Chinese Physics B 2015年第4期24卷 360-365页

作者： Muhammad Ammar khan 孙久勋 School of Physical Electronics University of Electronic Science and Technology

The mobility edge （ME） model with single Gaussian density of states （DOS） is simplified based on the recent exper- imental results about the Einstein relationship. The free holes are treated as being non-degenerate, and the trapped holes are dealt with as being degenerate. This enables the integral for the trapped holes to be easily realized in a program. The J-V curves are obtained through solving drift-diffusion equations. When this model is applied to four organic diodes, an obvious deviation between theoretical curves and experimental data is observed. In order to solve this problem, a new DOS with exponential tall is proposed. The results show that the consistence between J-V curves and experimental data based on a new DOS is far better than that based on the Gaussian DOS. The variation of extracted mobility with temperature can be well described by the Arrhenius relationship.

关键词： organic diode potential barriers Einstein relationship

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Some new generalized difference sequence spaces defined by a sequence of moduli

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 104-108页

作者： Vakeel A khan Department of Mathematics A. M. U. Aligarh-202002 India

The idea of difference sequence sets X（△） = {x = （xk）： △x ∈ X} with X = l∞, c and co was introduced by Kizmaz [12]. In this paper, using a sequence of moduli we define some generalized difference sequence sp... 详细信息

关键词： Difference sequence space sequence of moduli inclusion relation.

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Design and implementation of Ad-Hoc collaborative proxying scheme for reducing network energy waste

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Digital Communications and Networks 2017年第2期3卷 118-128页

作者： Rafiullah khan Sarmad Ullah khan School of Electronics Electrical Engineering and Computer Science Queen's University Belfast ECIT/CSIT- Northern Ireland Science Park Queen's RoadQueen's lsland Belfast BT3 9DT United Kingdom Electrical Engineering Department CECOS University of IT and Emerging Sciences Phase-6 Hayatabad Peshawar Pakistan

Network devices are equipped with low power states but they are rarely activated due to their inability of maintaining network connectivity. Recently, Network Connectivity Proxy （NCP） concept has been proposed in literature as an effective mechanism to exploit full potential of low power features on network devices by impersonating their virtual presence. However, the NCP concept faces several open issues and challenges especially related to proxying of TCP connections and majority of daily used proprietary dosed-source applications. This paper presents a new approach for reducing network energy waste through intelligent collaboration among daily used devices （e.g., desktop computers, laptops, tablets, smartphones, etc）. It guarantees to run applications on only and only one user device that is under active use at that specific moment. To reduce energy waste and allow idle devices to sleep, our approach also takes benefit from a light- weight home gateway proxy with very basic practically realizable functionalities. The proposed system not just reduces energy waste of fixed devices but also enables mobile devices to significantly improve their battery life. Our developed software prototypes allow devices to autonomously and seamlessly collaborate with each other without requiring any configuration or user input. Further, this paper also presents the basic performance evaluation of developed prototypes in real networking environments.

关键词： Green networking Energy efficiency Smartphone Home gateway proxy Power measurement Universal Plug & Play

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Liquid Phase Bonding of 316L Stainless Steel to AZ31 Magnesium Alloy

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Journal of Materials Science & Technology 2011年第1期27卷 22-28页

作者： Waled Elthalabawy Tahir khan Department of Mechanical and Manufacturing Engineering University of Calgary

The excellent corrosion resistance,formability and strength make stainless steels versatile for diverse ***,its high specific strength and good crashworthiness make it suitable for transportation and aerospace *** the other hand,the need to reduce the weight of vehicle and aerospace components has created renewed interest in the use of magnesium *** to their differences in physical and metallurgical properties,bonding of the 316L steel and AZ31 magnesium alloy using conventional fusion welding methods encountered many ***,the use of liquid phase forming interlayers is required to overcome the differences in their properties,eliminates the need for a high bonding pressure to achieve intimate contact between the bonded *** Cu and Ni interlayers successively formed a eutectic phase with *** formation of intermetallics and Mg diffusion caused the eutectic phase to isothermally solidify with increasing bonding *** formation of ternary intermetallic phases（λ1 and B2） impaired the bond shear strength particularly at the end of the isothermal solidification stage where no eutectic phase was ***,the joints showed a higher shear strength value of 57 MPa when bonding with Cu interlayer at 530℃ for 30 min compared to 32 MPa when Ni interlayer was used at 510℃ for 20 min.

关键词： Magnesium alloy Stainless steel Eutectic bonding Microstructure Shear strength

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Sagbi-Gröbner Bases Under Composition

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Journal of Systems Science & Complexity 2023年第5期36卷 2214-2224页

作者： KANWAL Nazish khan Junaid Alam Department of Sciences&Humanities FAST-National University of Computer&Emerging SciencesKarachicampusPakistan Department of Mathematical Sciences School of Mathematics and Computer ScienceInstitute of Business AdministrationKarachiPakistan

The process of substituting variables in a polynomial with other polynomials is dubbed polynomial *** behaviour of Gröbner bases and Sagbi bases under composition is well *** this paper,the authors provide a sufficient and necessary condition on a setΘof polynomials under which the Sagbi-Gröbner basis computation commutes with *** has natural applications to the computations of Sagbi-Gröbner bases for subsets of composed polynomials of subalgebra.

关键词： Polynomial composition sagbi bases Sagbi-Gr?bner bases

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Solving the Generalized Traveling Salesman Problem Using Sequential Constructive Crossover Operator in Genetic Algorithm

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Computer Systems Science & Engineering 2024年第5期48卷 1113-1131页

作者： zakir Hussain Ahmed Maha Ata Al-Furhood Abdul Khader Jilani Saudagar Shakir khan Department of Mathematics and Statistics College of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia Department of Computer Science College of Computer and Information SciencesJouf UniversitySakakah42421Saudi Arabia Information Systems Department Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia College of Computer and Information Sciences Imam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia

The generalized travelling salesman problem(GTSP),a generalization of the well-known travelling salesman problem(TSP),is considered for our *** the GTSP is NP-hard and very complex,finding exact solutions is highly expensive,we will develop genetic algorithms(GAs)to obtain heuristic solutions to the *** GAs,as the crossover is a very important process,the crossovermethods proposed for the traditional TSP could be adapted for the *** sequential constructive crossover(SCX)and three other operators are adapted to use in GAs to solve the *** effectiveness of GA using SCX is verified on some GTSP Library(GTSPLIB)instances first and then compared against GAs using the other crossover *** computational results show the success of the GA using SCX for this *** proposed GA using SCX,and swap mutation could find average solutions whose average percentage of excesses fromthe best-known solutions is between 0.00 and 14.07 for our investigated instances.

关键词： Generalized travelling salesman problem NP-hard genetic algorithms sequential constructive crossover swap mutation

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