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Communications in Theoretical Physics 2020年第7期72卷 1-7页

作者： H Wajahat A riaz Department of Mathematics China University of Mining and TechnologyBeijing100083China

We present a matrix coupled dispersionless(CD)system.A Lax pair for the matrix CD system is proposed and Darboux transformation is constructed on the solutions of the matrix CD system and the associated Lax *** express an N soliton formula for the solutions of the matrix CD system in terms of *** using properties of the quasideterminants,we obtain some exact solutions,including bright and dark-type solitons,rogue wave and breather solutions of the matrix CD ***,it has been shown that the solutions of the matrix CD system are expressed in terms of solutions to the usual CD system,sine-Gordon equation and Maxwell-Bloch system.

关键词： Matrix coupled dispersionless system Darboux transformation solitons

Adsorption of ruthenium ions on activated charcoal: influence of temperature on the kinetics of the adsorption process

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2005年第5期6卷 353-356页

作者： QADEER riaz Pakistan Atomic Energy Commission IslamabadPakistan

Influence of temperature on ruthenium adsorption on activated charcoal from 3 mol/L HNO3 solutions was inves- tigated in the temperature range of 288 K to 308 K. It was observed that the rise in temperature increases the adsorption of ru- thenium ions on activated charcoal and follows the kinetics of first order rate law with rate constant values 0.0564?0.0640 min?1 in the temperature range of 288 K to 308 K respectively. The activation energy for the adsorption process was found to be 1.3806 kJ/mol. Various thermodynamics quantities namely ?H, ?S and ?G were computed from the equilibrium constant KC values. The results indicated a positive heat of adsorption, a positive ?S and a negative ?G.

关键词： Ruthenium Activated charcoal Adsorption Kinetics Thermodynamic parameters Nitric acid solution

Effect of Reaction Temperature and Time on the Structural Properties of Cu(In,Ga)Se_2 Thin Films Deposited by Sequential Elemental Layer Technique

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Journal of Materials Science & Technology 2007年第4期23卷 499-503页

作者： Saira riaz Shahzad NASEEM Centre for Solid State Physics University of the Punjab QACLahore-54590Pakistan

Thin films of copper indium gallium selenide Cu（In,Ga）Se2 （CIGS） were prepared by sequential elemental layer deposition in vacuum at room temperature. The as-deposited films were heated in vacuum for compound formation, and were studied at temperature as high as 1250℃ for the first time. These films were concurrently studied for their structural properties by X-ray diffraction （XRD） technique. The XRD analyses include phase transition studies, grain size variation and microstrain measurements with the reaction temperature and *** has been observed that there are three distinct regions of variation in all these parameters. These regions belong to three temperature regimes：〈450℃, 450-950℃, and 〉950℃. It is also seen that the compound formation starts at 250℃, with ternary phases appearing at 350℃ or above. Whereas, there is another phase shift at 950℃ without any preference to the quaternary compound.

关键词： Cu(In,Ga)Se2 (CIGS) X-ray Diffraction Thin films Structural analysis

The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H W A riaz J Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

Principal Component Analysis and Minimum Description Length Criterion Based on Through-Wall Image Enhancement

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Chinese Physics Letters 2013年第4期30卷 45-47页

作者： Muhammad Mohsin riaz Abdul Ghafoor Department of Electrical Engineering College of SignalsNational University of Sciences and Technology(NUST)IslamabadPakistan

A through-wall image enhancement scheme is proposed based on principal component analysis and minimum description length *** minimum description length criterion is used with principal component analysis to extract target eigen *** proposed scheme is capable of extracting multiple targets from heavy cluttered through-wall *** results of the proposed scheme are compared with existing schemes on the basis of quantitative analysis and visual inspection.

关键词： criterion. Image scheme

Accelerated Iterative Learning Control for Linear Discrete Systems with Parametric Perturbation and Measurement Noise

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Computer Modeling in Engineering & Sciences 2022年第8期132卷 605-626页

作者： Xiaoxin Yang Saleem riaz School of Energy and Architecture Xi’an Aeronautical UniversityXi’an710077China School of Automation Northwestern Polytechnical UniversityXi’an170072China

An iterative learning control algorithm based on error backward association and control parameter correction has been proposed for a class of linear discrete time-invariant systems with repeated operation characteristics,parameter disturbance,and measurement noise taking PD type ***,the concrete form of the accelerated learning law is presented,based on the detailed description of how the control factor is obtained in the ***,with the help of the vector method,the convergence of the algorithm for the strict mathematical proof,combined with the theory of spectral radius,sufficient conditions for the convergence of the algorithm is presented for parameter determination and no noise,parameter uncertainty but excluding measurement noise,parameters uncertainty and with measurement noise,and the measurement noise of four types of scenarios ***,the theoretical results show that the convergence rate mainly depends on the size of the controlled object,the learning parameters of the control law,the correction coefficient,the association factor and the learning *** results show that the proposed algorithm has a faster convergence rate than the traditional PD algorithm under the same conditions.

关键词： Iterative learning control monotone convergence convergence rate gain adjustment

Visible–light driven photocatalytic degradation of bisphenol-A using ultrasonically synthesized polypyrrole/K-birnessite nanohybrids:Experimental and DFT studies

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Journal of Environmental Sciences 2019年第5期31卷 161-173页

作者： Jannatun Zia Mohamed Ajeer Ufana riaz Materials Research Laboratory Department of ChemistryJamia Millia Islamia

Although manganese oxides are known for their semiconductor characteristics, the photocatalytic performance of conducting polymer intercalated K-Birnessite(K-Bi) has not been explored till date. With the view to design a visible light driven organic–inorganic hybrid photocatalyst for rapid degradation of Bisphenol A(BPA), the present work reports the ultrasound-assisted green synthesis of K-Bi/polypyrrole(Ppy) nanohybrids. The loading of Ppy in K-Bi was confirmed by thermogravimetric analysis while the formation of organic–inorganic hybrid was confirmed by infrared spectroscopy. K-Bi revealed a band gap of 2.8 e V while for the nanohybrids it was found to be ranging between 2.4 and 1.6 e V. X-ray diffraction studies confirmed partial intercalation of Ppy chains in the inter-layer space of K-Bi. High resolution transmission electron microscopy and scanning electron microscopy studies showed mixed morphology of K-Birnessite/Ppy nanohybrids. Rapid degradation of BPA was observed under visible irradiation in presence of K-Bi/Ppy nanohybrids and almost90% degradation of 20 mg/L BPA solution was achieved within 120 min. The degradation was found to follow pseudo-first order kinetics and the degraded fragments were identified using liquid chromatography-mass spectrometry. Degradation pathway was proposed based on density-functional theory calculations of fukui index predicting the radical easyattacking(f0) and(f-) sites in BPA.

关键词： Photocatalysis Degradation kinetics Manganese oxide Polypyrrole DFT calculations

Darboux Transformation for a Negative Order AKNS Equation

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Communications in Theoretical Physics 2019年第8期71卷 912-920页

作者： H.Wajahat A.riaz Department of Physics University of Punjab Quaid-e-Azam Campus

Using a quasideterminant Darboux matrix, we compute soliton solutions of a negative order AKNS(AKNS(-1)) *** transformation(DT) is defined on the solutions to the Lax pair and the AKNS(-1)*** iterated DT to K-times, we obtain multisoliton *** has been shown that multisoliton solutions can be expressed in terms of quasideterminants and shown to be related with the dressed solutions as obtained by dressing method.

关键词： integrable systems solitons Darboux transformation quaside terminants

Laser-assisted ablation and plasma formation of titanium explored by LIBS,QCM, optical microscopy and SEM analyses along with mechanical modifications under different pressures of Ar and Ne

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Plasma Science and Technology 2023年第3期25卷 181-192页

作者： Maryam riaz Shazia BASHIR Asma HAYAT Zarish NAZ Centre for Advanced Studies in Physics GC University Lahore

This study deals with the investigation of Nd:YAG laser-assisted ablation and plasma formation of Ti at irradiance of 0.85 GW cm-2 under Ar and Ne environment at various pressures ranging from 10-120 ***-induced breakdown spectroscopy is used to evaluate plasma parameters,whereas quartz crystal microbalance is used for ablation yield *** crater depth is evaluated by optical *** surface features are explored by scanning electron microscope(SEM) analysis and the micro-hardness is measured by a Vickers hardness *** is observed that the plasma parameters are higher in Ar than in Ne,and are strongly correlated with the ablation yield,ablation depth,surface features and hardness of laser-ablated *** parameters increase with increasing the pressure of environmental gases,attain their maxima at 40 Torr for Ar and at 60 Torr for ***,they show a decreasing trend up till a maximum pressure of 120 *** maximum value of the electron temperature(Te) is5480 K,number density(ne) is 1.46 × 1018 cm-3,ablation depth is 184 μm,ablation yield is3.9 × 1015 atoms/pulse and hardness is 300 HV in the case of Ar *** analysis reveals the growth of surface features,such as cones,ridges and pores,whose appearance is more distinct in Ar than Ne and is attributed to temperature,pressure and density gradients along with recoil pressure of the Ti plasma.

关键词： ablation plasma electron temperature electron density laser-induced breakdown spectroscopy surface structures