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Communications in Theoretical Physics 2015年第8期64卷 208-214页

作者： m.G.shah m.m.Rahman m.R.Hossen A.A.mamun Department of Physics Jahangirnagar University Department of Natural Sciences Daffodil International University

Heavy-ion-acoustic(HIA) waves in an unmagnetized collisionless plasma system comprising superthermal electrons, Boltzmann distributed light ions, and adiabatic positively charged inertial heavy ions have been investigated both numerically and analytically. The well-known reductive perturbation method has been used to derive the Kortewegde Vries(K-d V) and Burgers(BG) equations. The parametric regimes for the existence of both the positive and negative solitary and shock waves have been obtained. The effects of adiabaticity of heavy ions and superthermality of electrons,which are found to notably modify the fundamental features(viz. polarity, amplitude, phase speed, etc.) of HIA solitary and shock waves, are precisely studied. The results of our theoretical investigation can be applicable to understand the characteristics and basic nonlinear structures of HIA waves both in space and laboratory plasma situations.

关键词： heavy-ion acoustic waves superthermality adiabatic

Instability Analysis of Positron-Acoustic Waves in a magnetized multi-Species Plasma

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Communications in Theoretical Physics 2017年第4期67卷 458-466页

作者： m.A.Hossen m.G.shah m.R.Hossen A.A.mamun Department of Physics Jahangirnagar UniversitySavarDhaka-1342Bangladesh Department of Physics Hajee Mohammad Danesh Science and Technology UniversityDinajpur-5200Bangladesh Department of General Educational Development Daffodil International UniversitySukrabadDhaka-1207Bangladesh

The nonlinear propagation of electrostatic excitations and their multi-dimensional instability in a magnetized, degenerate electron-positron-ion(EPI) plasma system(containing inertial cold positrons, relativistic degenerate electrons and hot positrons, and negatively charged immobile heavy ions) are theoretically investigated. The reductive perturbation method is employed to derive the Zakharov–Kuznetsov equation which admits a localized solitary wave solution for small but finite amplitude limit, and the multi-dimensional instability of the positron acoustic solitary waves(PASWs) is studied by the small-k perturbation expansion method. It is found that the basic characteristics(viz. phase speed, amplitude, width) of the PASWs are significantly affected by the degree of obliqueness, relativistic degeneracy,and plasma particle number densities. The instability criterion and its growth rate, which are depending on the magnetic field and the propagation directions of both the PASWs, and their perturbation modes are discussed. The present analysis can be helpful in understanding the nonlinear phenomenon in dense astrophysical as well as space plasma systems,especially in pulsar environments.

关键词： instability analysis solitary waves magnetized plasma degeneracy relativistic effect

Unsupervised neural network model optimized with evolutionary computations for solving variants of nonlinear mHD Jeffery-Hamel problem

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Applied mathematics and mechanics(English Edition) 2015年第12期36卷 1611-1638页

作者： m.A.Z.RAJA R.SAmAR T.HAROON S.m.shah Department of Electrical Engineering COMSATS Institute of Information Technology Department of Electrical Engineering Mohammad Ali Jinnah University Department of mathematics COMSATS Institute of Information Technology

A heuristic technique is developed for a nonlinear magnetohydrodynamics （mHD） Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work （ANN） optimized with the genetic algorithm （GA） and the sequential quadratic programming （SQP） method. The twodimensional （2D） mHD Jeffery-Hamel problem is transformed into a higher order boundary value problem （BVP） of ordinary differential equations （ODEs）. The mathematical model of the transformed BVP is formulated with the ANN in an unsupervised manner. The training of the weights of the ANN is carried out with the evolutionary calculation based on the GA hybridized with the SQP method for the rapid local convergence. The proposed scheme is evaluated on the variants of the Jeffery-Hamel flow by varying the Reynold number, the Hartmann number, and the an- gles of the walls. A large number of simulations are performed with an extensive analysis to validate the accuracy, convergence, and effectiveness of the scheme. The comparison of the standard numerical solution and the analytic solution establishes the correctness of the proposed designed methodologies.

关键词： Jeffery-Hamel problem neural network genetic algorithm (GA) nonlinear ordinary differential equation (ODE) hybrid technique sequential quadratic programming

Removal of Rhodamine B from aqueous solutions and wastewater by walnut shells： kinetics, equilibrium and thermodynamics studies

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Frontiers of Chemical Science and Engineering 2013年第4期7卷 428-436页

作者： Jasmin shah m. Rasul Jan Attaul Haq Younas Khan Institute of Chemical Sciences University of Peshawar Peshawar Pakistan

An adsorption study ofRhodamine B （RB） dye from aqueous solutions was carried out using walnut shells pretreated by different methods. In addition to the effects of the pretreatment, the effects of various parameters like pH, adsorbent dose, contact time, initial dye concentration and temperature on the adsorption of RB was studied. The adsorption process was highly pH dependent and a maximum adsorption was achieved at pH 3.0. The best fit for the rates of dye adsorption was a pseudo-second- order kinetic model with good correlation coefficients （R2〉 0.99）. Langmuir isotherms were used to determine that the maximum loading capacity of the different walnut shells and the RB capacities ranged from 1.451-2.292 mg ~ gl. The dye adsorption was also evaluated thermodyna- mically. Positive standard enthalpy （m-P） values were obtained indicating that the RB adsorption process is endothermic as well as AG~ and AS~ values showed that adsorption process is spontaneous with an increased randomness at the solid-liquid interface~ Desorption studies were carried out to explore the feasibility of regenerating the used walnut shells and it was found that 97~71%-99.17% of the retained RB was recovered with 0.1 mol＂ L 1 NaOH solution. The walnut shells were also successfully used to remove RB from industrial effluents.

关键词： Rhodamine B walnut shell adsorption,kinetics isotherms regeneration

Time-Resolved Emission Spectroscopic Study of Laser-Induced Steel Plasmas

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Plasma Science and Technology 2013年第6期15卷 546-551页

作者： m.L.shah A.K.PULHANI B.m.SURI G.P.GUPTA Laser and Plasma Technology Division Bhabha Atomic Research CentreMumbai-400 085India

Laser-induced steel plasma is generated by focusing a Q-switched Nd：YAG visible laser（532 nm wavelength） with an irradiance of 1 x 109 W/cm2 on a steel sample in air at atmospheric *** Echelle spectrograph coupled with a gateable intensified charge-coupled detector is used to record the plasma *** time-resolved spectroscopic measurements of the plasma emissions,the temperature and electron number density of the steel plasma are determined for many times of the detector *** validity of the assumption by the spectroscopic methods that the laser-induced plasma（LIP） is optically thin and is also in local thermodynamic equilibrium（LTE） has been evaluated for many delay *** the temporal evolution of the intensity ratio of two Fe I lines and matching it with its theoretical value,the delay times where the plasma is optically thin and is also in LTE are found to be 800 ns,900 ns and 1000 ns.

关键词： laser-induced plasma steel emission spectroscopy plasma temperature and electron number density

Dust-Lower-Hybrid Surface Waves in Classical and Degenerate Plasmas

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Communications in Theoretical Physics 2013年第11期60卷 623-629页

作者： m.Ayub H.A.shah m.N.S.Qureshi m.Salimullah Department of Physics G. C. University Department of Physics Mirpur University of Science and Technology (MUST) Department of Physics Jahangirnagar University

The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a magnetized dusty plasma region and a vacuum is derived by using specular reflection boundary conditions both in classical and quantum regimes. The frequency limit ω ≤ωei ≤ ωce is considered and the dispersion relation for the Dust-Lower-Hybrid Surface Waves （DLHSW＇s） is derived for both classical and quantum plasma half-space and analyzed numerically. It is shown that the wave behavior changes as the quantum nature of the problem is considered.

关键词： dusty plasma lower hybird surface wave degenerate plasma

Enhancement in antinociceptive and anti-inflammatory effects of tramadol by transdermal proniosome gel

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Asian Journal of Pharmaceutical Sciences 2020年第6期15卷 786-796页

作者： Jigar shah Anroop B.Nair Hiral shah Shery Jacob Tamer m.Shehata mohamed Aly morsy Institute of Pharmacy Nirma UniversityAhmedabad 382481India College of Clinical Pharmacy King Faisal UniversityAl-Ahsa 31982Saudi Arabia Arihant School of Pharmacy&BRI Gandhinagar 382421India College of Pharmacy Gulf Medical UniversityAjman 4184United Arab Emirates Faculty of Pharmacy University of ZagazigZagazig 44519Egypt Faculty of medicine Minia UniversityEl-Minia 61511Egypt

Oral therapy of tramadol,an opiate analgesic,undergoes extensive hepatic metabolism and requires frequent *** therapy by virtue can overcome these issues and can improve the efficacy and reduce abuse liability of *** aim of this research was to investigate the possibility of transdermal delivery of tramadol by formulating proniosome gel and evaluate its therapeutic potential in *** effect of formulation composition as well as amount of drug on physicochemical characteristics of prepared proniosomes were *** proniosome gel(F4)was selected and evaluated for drug release,stability and transdermal efficacy by ex vivo and in vivo *** vesicles demonstrated optimal properties including spherical shape,nanosize with good entrapment efficiency,adequate zeta potential,higher stability and greater transdermal *** amorphization and dispersion of tramadol in the aqueous core of proniosome vesicles was confirmed by differential scanning *** profile of F4 was distinct(Pm control and displayed steady and prolonged tramadol release by Fickian *** therapy of F4 showed prominent reduction of induced twitches(Pmice and edema(Pmpared to oral *** improvement in clinical efficacy of tramadol in transdermal therapy is correlated with the pharmacokinetic data *** conclusion,the observed improvement in antinociceptive and anti-inflammatory effects from proniosome carriers signifies its potential to be a suitable alternative to oral therapy of tramadol with greater efficacy.

关键词： Tramadol Proniosomes Flux Edema Pharmacokinetics Rats

In vitro and in vivo bactericidal activity of Vitex negundo leaf extract against diverse multidrug resistant enteric bacterial pathogens

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Asian Pacific Journal of Tropical medicine 2013年第5期6卷 133-140页

作者： muhammad Kamruzzaman S.m.Nayeemul Bari shah m.Faruque molecular Genetics Laboratory International Centre for Diarrhoeal Disease ResearchBangladeshDhaka-1212Bangladesh

Objective:To investigate in vitro and in vivo antibacterial potentials of Vitex negundo(V. negundo) leaf extracts against diverse enteric ***:Water and methanol extracts of *** leaves were evaluated against enteric bacterial pathogens by using standard disc diffusion,viable bacterial cell count methods,determination of minimum inhibitory concentrations(mIC) and minimum bactericidal concentrations(mBC).Results:methanol extract of *** leaves showed potent antibacterial activity(inhibition zone:9.9- 22.6 mm,mIC: 200-3 200μg/mL,mBC:200-6 400μg/mL) against all the pathogenic enleric bacteria(Vibrio cholerae,Vibrio parahaemolyticus,Vibrio mimicus,Echerichia *** spps.,and Aeromonas spps) *** extract of *** leaves showed potent bactericidal activity both in vitro laboratory conditions(mBC,200-400μg/mL) and in the intestinal environment(Dose,1-2 mg/mL) of infant mice against pathogenic Vibrio cholerae,the major causative agent of cholera. Furthermore,assays using the mice cholera model showed that *** methanol extract can protect mice from Vibrio cholerae infection and significantly decrease the mortality rate(Pme we showed that methanol extract of *** leaves exhibited strong vibriocidal activity both in vitro and in vivo ***,it will be useful to identify and isolate the active compounds of this extract that could be a good alternative of antibiotics to treat cholera.

关键词： Bactericidal activity Vitex negundo Enteric pathogenic bacteria

Chemical study of limestone and clay for cement manufacturing in Darukhula,Nizampur District,Nowshera,North West Frontier Province(N.W.F.P.),Pakistan

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Chinese Journal Of Geochemistry 2008年第3期27卷 242-248页

作者： Khurshid Ali Noor-ul-Amin m.Tahir shah Institute of Chemical Sciences University of Peshawar Pakistan National Center of Excellence in Geology University of PeshawarPakistan

Limestone and clay samples were collected from Darukhula and adjoining areas of the Nizampur District,Nowshera,N.W.F.P.,Pakistan,and analyzed for different parameters in order to search for new reserves of suitable material for the manufacture of different types of cements in *** was found that the area under study contains three types of limestones,including high grade limestone,Darukhula limestone and siliceous limestone,which contain 53%,49.03% and 45.19% CaO,respectively,and three types of clay,including maroon color,yellow to yellowish-green color and green color clay containing 57.76%,65.47% and 61.24% SiO2,*** analysis of the limestone and clay samples collected from the deposits in the area under study showed that all the elements found in these samples are within the range of permissible limits for the production of high-strength Portland cement,sulphate resisting cement and white *** paper covers the detailed version of the potential raw material deposits at Darukhula and adjoining areas of the Nizampur District.

关键词：水泥原材料 N.W.F.P. 化学制品黏土

Wavelet Decomposition Impacts on Traditional Forecasting Time Series models

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Computer modeling in Engineering & Sciences 2022年第3期130卷 1517-1532页

作者： W.A.Shaikh S.F.shah S.m.Pandhiani m.A.Solangi Department of mathematics and Statistics Quaid-e-Awam University of EngineeringScience&TechnologyNawabshahSindhPakistan Department of Basic Sciences&Related Studies Mehran University of Engineering&TechnologyJamshoroSindhPakistan Department of General Studies Jubail University CollegeAl JubailSaudi Arabia

This investigative study is focused on the impact of wavelet on traditional forecasting time-series models,which significantly shows the usage of wavelet *** Decomposition(WD)algorithm has been combined with various traditional forecasting time-series models,such as Least Square Support Vector machine(LSSVm),Artificial Neural Network(ANN)and multivariate Adaptive Regression Splines(mARS)and their effects are examined in terms of the statistical *** WD has been used as a mathematical application in traditional forecast modelling to collect periodically measured parameters,which has yielded tremendous constructive ***,it is observed that the wavelet combined models are classy compared to the various time series models in terms of performance ***,combining wavelet forecasting models has yielded much better results.

关键词： Impact wavelet decomposition combined traditional forecasting models statistical analysis