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Chinese Physics B 2013年第3期22卷 57-62页

作者： Reda G.Abdel-rahman m.m.Khader Ahmed m.megahed Department of mathematics Faculty of ScienceBenha University

The Lie group method is applied to present an analysis of the magneto hydro-dynamics（mHD） steady laminar flow and the heat transfer from a warm laminar liquid flow to a melting moving surface in the presence of thermal *** using the Lie group method,we have presented the transformation groups for the problem apart from the scaling *** application of this method reduces the partial differential equations（PDEs） with their boundary conditions governing the flow and heat transfer to a system of nonlinear ordinary differential equations（ODEs） with appropriate boundary *** resulting nonlinear system of ODEs is solved numerically using the implicit finite difference method（FDm）.The local skin-friction coefficients and the local Nusselt numbers for different physical parameters are presented in a table.

关键词： Lie group method magneto hydro-dynamics melting phenomenon Newtonian fluid radiation

Analysis of Proteotranscriptomics Landscape Reveals Differentially Regulated Pathways in Toxoplasma gondii Infected mouse Liver

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Computational molecular Bioscience 2022年第1期12卷 20-57页

作者： Tanzina Tarannum md. Saruar Alam atiqur rahman Sajib Chakraborty Hossain Uddin Shekhar Taibur rahman Laboratory of Infection Biology Department of Biochemistry and Molecular Biology University of Dhaka Dhaka Bangladesh Laboratory Clinical Biochemistry and Translational medicine Department of Biochemistry and Molecular Biology University of Dhaka Dhaka Bangladesh

Toxoplasma gondii (T. gondii) an intracellular protozoan parasite, infects mammals including human population world-wide. Upon primary infection, the parasite contributes to mild flu like symptoms in immune competent host, but life threatening complication is seen in immune compromised patients and in pregnant women. Understanding the host-parasite interaction is critical for understanding the pathogenesis and biology parasite reactivation in the host. In this study, we used proteotrasncriptomics analyses by integrating the transcriptomics and proteomics data of T. gondii infected mouse liver to uncover the effector molecules responsible for disease pathogenesis that can be used as candidate markers for diagnosis and drug target. With this aim, we systematically integrated transcriptomicand proteomic data, representing the parasite infected mouse liver. Out of 2758 differentially expressed genes (DEGs) and 301 differentially expressed proteins (DEPs), 159 overlapping genes were identified. Among them, 86 genes were upregulated and 72 were downregulated in their respective mRNA and protein levels in the infected condition. Gene Ontology (GO) analysis revealed that the upregulated genes were mostly associated with immune system processes whereas the downregulated genes were involved in oxidation-reduction process and metabolism of lipid, and fatty acids. Protein-protein interaction (PPI) network analysis uncovered an interaction-hub including, Psmb8, Psmb9 and Tap1 for upregulated proteins and Cyp1A2, Cyp4A10 and Cyp3A11 for down-regulated proteins. Further studies are needed to validating these effector molecules. These molecules are likely to play a vital role in disease pathogenesis, as well as can be used as potential diagnostic marker and drug target candidates.

关键词： Toxoplasma gondii Transcriptome Proteome mouse Liver Differentially Expressed Genes and Proteins Gene Ontology Analysis Protein-Protein Interaction Hub-Proteins Homology modeling Effector molecules

Photodetachment of H^(-) near a Hard Spherical Surface

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Chinese Physics Letters 2012年第1期29卷 90-93页

作者： m.Haneef Iftikhar Ahmad A.Afaq A.rahman Department of Physics Hazara UniversityMansehraPakistan Department of Physics University of MalakandChakdaraPakistan Centre of Excellence in Solid State Physics University of the PunjabQuid-e-Azam CampusLahore-54590Pakistan

The photodetachment of a hydrogen negative ion (H^(-)) near a hard spherical surface is investigated by using the theoretical imaging *** surface is oriented in such a fashion that the laser polarization direction is perpendicular to the principal axis of the spherical *** expressions are derived for the detachedelectron flux and photodetachment cross *** interference patterns are observed in the detachedelectron flux,while no visible oscillations are found in the photodetachment cross section.

关键词： visible polarization Strong

Interferences in Photodetached Electron Spectra from a Linear Tetra-Atomic Negative Ion

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Chinese Physics Letters 2011年第6期28卷 102-105页

作者： A.rahman Iftikhar Ahmad A.Afaq m.Haneef Department of Physics Hazara UniversityMansehraPakistan Centre of Excellence in Solid State Physics University of the PunjabQuid-e-Azam CampusLahore-54590Pakistan

Photo-detached electron spectra from a hypothetical linear tetra-atomic negative ion is obtained.A plane polarized laser parallel to the axis of the molecular ion is used to knock off the loosely bound *** spectrum of the detached-electron flux shows strong interference peaks,while the number of peaks increases with the increase in the photon *** oscillations are also observed in the total photodetachment cross section *** frequency of the oscillations increases with the increase in the distance between the successive atoms d in the linear *** quantum interference effects vanish for very large d or very high photon energy.

关键词： spectrum energy successive

Impacts of Heat Flux Distribution, Sloping magnetic Field and magnetic Nanoparticles on the Natural Convective Flow Contained in a Square Cavity

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Fluid Dynamics & materials Processing 2020年第3期16卷 441-463页

作者： Latifa m.Al-Balushi m.m.rahman Department of mathematics College of ScienceSultan Qaboos UniversityMuscatOman

In the present paper,the effect of the heat flux distribution on the natural convective flow inside a square cavity in the presence of a sloping magnetic field and magnetic nanoparticles is explored *** nondimensional governing equations are solved in the framework of a finite element method implemented using the Galerkin *** role played by numerous model parameters in influencing the emerging thermal and concentration fields is examined;among them are:the location of the heat source and its lengthH,the magnitude of the thermal Rayleigh number,the nanoparticles shape and volume fraction,and the Hartmann *** is found that the nanofluid velocity becomes higher when the thermal source length,the nanoparticles volume fraction and/or the thermal Rayleigh number are increased,while it decreases as the Hartmann number Ha grows and the position of the heat source moves toward the center of the lower wall of the ***,the temperature of the nanofluid grows with the extension of the thermal source and decreases slowly when the heat flux position moves toward the center of the lower *** outcomes of the research also indicate that the average Nusselt number becomes smaller on increasing Hartmann number Ha and heat source length H^(*).The addition of Fe_(3)O_(4) to engine oil leads to a higher rate of heat transfer with respect to the addition of SiO_(2) ***-shaped nanoparticles generate the highest value of the Nusselt number compared to all the other considered shapes.

关键词： Nanofluids magnetic nanoparticles heat source natural convection finite element method square enclosure

Cylindrical and Spherical Electron-Acoustic Shock Waves in Electron-Positron-Ion Plasmas with Nonextensive Electrons and Positrons

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Communications in Theoretical Physics 2015年第2期63卷 243-248页

作者： A.Rafat m.m.rahman m.S.Alam A.A.mamun Department of Physics Jahangirnagar University

Electron-acoustic shock waves （EASWs） in an unmagnetized four-component plasma （containing hot elec- trons and positrons following the q-nonextensiv.e distribution, cold mobile viscous electron fluid, and immobile positive ions） are studied in nonplanar （cylindrical and spherical） geometry. With the help of the reductive perturbation method, the modified Burgers equation is derived. Analytically, the effects of nonplanar geometry, nonextensivity, relative number density and temperature ratios, and cold electron kinematic viscosity on the basic properties （viz. amplitude, width, speed, etc.） of EASWs are discussed. It is exarmined that the EASWs in nonplanar geometry significantly differ from those in planar geometry. The results of this investigation can be helpful in understanding the nonlinear features of EASWs in various astrophysical plasmas.

关键词： electron-acoustic shock waves electron-positron-ion plasmas modified Burgers equation nonpla-nar geometry nonextensivity

A ROUGH SET APPROACH TO FEATURE SELECTION BASED ON SCATTER SEARCH mETAHEURISTIC

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Journal of Systems Science & Complexity 2014年第1期27卷 157-168页

作者： WANG Jue ZHANG Qi ABDEL-rahman Hedar ABDEL-mONEm m Ibrahim Center for Forecasting Science Academy of Mathematics and System Science Chinese Academy of ScienceBeijing 100190 China. Department of Computer Science Faculty of Computers and Information Assiut University Assiut 71516Egypt.

Rough set theory is an effective method to feature selection, which has recently fascinated many researchers. The essence of rough set approach to feature selection is to find a subset of the original features. It is, however, an NP-hard problem finding a minimal subset of the features, and it is necessary to investigate effective and efficient heuristic algorithms. This paper presents a novel rough set approach to feature selection based on scatter search metaheuristic. The proposed method, called scatter search rough set attribute reduction （SSAR）, is illustrated by 13 well known datasets from UCI machine learning repository. The proposed heuristic strategy is compared with typical attribute reduction methods including genetic algorithm, ant colony, simulated annealing, and Tabu search. Computational results demonstrate that our algorithm can provide efficient solution to find a minimal subset of the features and show promising and competitive performance on the considered datasets.

关键词： Attribute reduction computational intelligence metaheuristics rough set scatter search.

Extraction and characterization of alumina nanopowders from aluminum dross by acid dissolution process

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International Journal of minerals,metallurgy and materials 2015年第4期22卷 429-436页

作者： Saifur rahman Sarker Zahangir Alam Rakibul Qadir m A Gafur mohammad moniruzzaman Department of Applied Chemistry and Chemical Engineering University of Dhaka Pilot Plant & Project Development Centre (PP& PDC) Bangladesh Council of Scientific and Industrial Research (BCSIR) BCSIR Laboratories Dhaka

A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI（OH）3 was produced in the form of a gel. Calcination of the AI（OH）3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, （t~＋O）-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI（OH）3 gel was performed by thermogravimetric/differential thermal analysis （TG/DTA） and differential scanning calo- rimetry （DSC）. The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence （XRF） spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.

关键词： aluminum dross alumina nanoparticles acid dissolution calcination X-ray fluorescence analysis

Bilirubin sensor based on CuO-CdO composites deposited in a nafion/glassy carbon electrode matrixes

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Progress in Natural Science:materials International 2017年第5期27卷 566-573页

作者： mohammed m.rahman mohammad musarraf Hussain Abdullah m.Asiri Chemistry Department King Abdulaziz UniversityFaculty of Science Center of Excellence for Advanced material Research (CEAmR) King Abdulaziz University

Copper oxide-cadmium oxide nanocomposites(CuO-CdO NCs) were synthesized by solvothermal technique in a basic medium. CuO-CdO NCs were characterized using conventional techniques, such as Fourier Transform Infrared Spectroscopy(FTIR), UV–Visible Spectroscopy(UV/Vis), Field-Emission Scanning Electron microscopy(FESEm), X-ray electron dispersive spectroscopy(XEDS), X-ray photoelectron spectroscopy(XPS), and powder X-ray diffraction(XRD). A selective and enzyme-less Bilirubin(BLR) sensor was developed with a thin-layer of NCs onto a glassy carbon electrode(GCE, surface area = 0.0316 cm~2) using 5% nafion binders at room conditions. Improved electrochemical performances of higher sensitivity, lower detection limit,linear dynamic range(LDR), and long-term stability of preferred BLR were achieved by a reliable currentvoltage(I-V) approach. The calibration curve was found linear(R~2= 0.9347) in a wide range of BLR concentration(10.0 pm ~ 10.0 mm). Based on the signal to noise ratio value of 3, the sensitivity and limit of detection(LOD) of the sensor were calculated as 95.0 pA μm-1cm-2and 1.0 ± 0.1 pm *** synthesized CuO-CdO NCs/GCE is an excellent advancement of developing a selective and sensitive BLR sensor by electrochemical approach and practically implemented in real sample applications.

关键词： CuO-CdO nanocomposites Bilirubin biosensor Glassy carbon electrode Sensitivity Real sample analysis Health care field

Effect of annealing on properties of mg doped Zn-ferrite nanoparticles

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Progress in Natural Science:materials International 2015年第2期25卷 111-116页

作者： K.Nadeem S.rahman m.mumtaz materials Research laboratory Department of Physics International Islamic University

A comparison of structural and magnetic properties of as-prepared and annealed(900 1C) mg doped Zn ferrite nanoparticles(Zn1 xmgxFe2O4,with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5) is presented. X-ray diffraction(XRD) studies confirmed the cubic spinel structure for both the as-prepared and annealed nanoparticles. The average crystallite size and lattice parameter were increased by annealing. Scanning electron microscopy(SEm)images also showed that the average particle size increased after annealing. Fourier transform infrared spectroscopy(FTIR) also confirmed the spinel structure for both series of nanoparticles. For both annealed and as-prepared nanoparticles, the O–mtet.–O vibrational band shifts towards higher wave numbers with increased mg concentration due to cationic rearrangement on the lattice sites. magnetization studies revealed an anomalous decreasing magnetization for the annealed nanoparticles which is also ascribed to cationic rearrangement on the lattice sites after annealing. The measurement of coercivity showed a decreasing trend by annealing due to the increased nanoparticle size and better crystallinity.

关键词： Nanoparticles Annealing Ferrites Spinel structure magnetic properties