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Nanoscale mass sensing based on vibration of single-layered graphene sheet in thermal environments

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Acta Mechanica sinica 2014年第1期30卷 84-91页

作者： s.ahmad Fazelzadeh Esmaeal Ghavanloo school of Mechanical Engineering Shiraz University

Based on vibration analysis, single-layered graphene sheet （sLGs） with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of sLGs-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the sLGs- based mass sensor increases with increasing temperature difference.

关键词： Vibration - single-layered graphene sheet. Ther- mal environment - Nonlocal elasticity theory Relative frequency shift

Damped Kadomtsev–Petviashvili Equation for Weakly Dissipative solitons in Dense Relativistic Degenerate Plasmas

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Communications in Theoretical Physics 2017年第12期67卷 783-790页

作者： s.ahmad Ata-ur-Rahman s.A.Khan F.Hadi Department of Physics University of Kotli Azad Jammu and Kashmir Department of Physics Theoretical Plasma Physics Group Islami a College Peshawar (A Public Sector University) National Centre for Physics Quaid-i-Azam University Campus Department of Nuclear Engineering Kyoto University Department of Applied Physical and Material sciences University of Swat

We have investigated the properties of three-dimensional electrostatic ion solitary structures in highly dense collisional plasma composed of ultra-relativistically degenerate electrons and non-relativistic degenerate ions. In the limit of low ion-neutral collision rate, we have derived a damped Kadomtsev–Petviashvili(KP) equation using perturbation analysis. supplemented by vanishing boundary conditions, the time varying solution of damped KP equation leads to a weakly dissipative compressive soliton. The real frequency behavior and linear damping of solitary pulse due to ion-neutral collisions is discussed. In the presence of weak transverse perturbations, soliton evolution with damping parameter and plasma density is delineated pointing out the extent of propagation using typical parameters of dense plasma in the interior of white dwarfs.

关键词： dissipative solitons damped Kadomtsev–Petviashvili equation

Investigations of Viscous Dissipation in stagnation Point Flow Past a stretchable Riga Wall: Modern Analysis of Heat Transport

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Communications in Theoretical Physics 2019年第4期71卷 377-383页

作者： Aisha Anjum N.A.Mir M.Farooq M.Javed s.ahmad Department of Mathematics Riphah International University

This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out in Cattaneo-Christov diffusion analysis for the ?rst time in this letter. As a result of Cattaneo-Christov model, some extra terms of viscous dissipation are appeared in the energy equation. These extra terms of viscous dissipation are missing in the literature. On the utilization of suitable transformations, the equations governing the problem are reduced under the boundary layer approximation into the non-linear and dimensionless ordinary differential equations. Convergent approach is utilized to solve the dimensionless governing equations. The solution thus acquired is used to highlight the effects of emerging parameters on velocity distribution and ?uid's temperature through the graphs. Features of the drag force(or skin friction co-e?cient) are graphically interpreted. It is noticed that the presence of modi?ed Hartman number helps to reduce the ?uid's temperature but enhances the velocity pro?le. Further an enlargement in the value of thermal time relaxation parameter helps to decrease the temperature distribution.

关键词： stagnation point Cattaneo-Christov theory Riga plate linear stretching viscous dissipation

Pulsed ion beam-assisted carburizing of titanium in methane discharge

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Chinese Physics B 2010年第1期19卷 247-256页

作者： M.shafiq M.Hassan K.shahzad A.Qayyum s.ahmad R.s.Rawat M.Zakaullah Department of Physics Quaid-i-Azam University Department of Physics GC University National Tokamak Fusion Program Natural sciences and science Education National Institute of EducationNanyang Technological University

The carburizing of titanium （Ti） is accomplished by utilizing energetic ion pulses of a 1.5 kJ Mather type dense plasma focus （DPF） device operated in methane discharge. X-ray diffraction （XRD） analysis confirms the deposition of polycrystalline titanium carbide （TIC）. The samples carburized at lower axial and angular positions show an improved texture for a typical （200）TIC plane. The Williamson-Hall method is employed to estimate average crystallite size and microstrains in the carburized Ti surface. Crystallite size is found to vary from - 50 to 100 nm, depending on the deposition parameters. Microstrains vary with the sample position and hence ion flux, and are converted from tensile to compressive by increasing the flux. The carburizing of Ti is confirmed by two major doublets extending from 300 to 390 cm^-1 and from 560 to 620 cm^-1 corresponding to acoustic and optical active modes in Raman spectra, respectively. Analyses by scanning electron microscopy/energy dispersive x-ray spectroscopy （sEM/EDs） have provided qualitative and quantitative profiles of the carburized surface. The Vickers microhardness of Ti is significantly improved after carburizing.

关键词： carbide plasma focus microstructure surface morphology

Toxin(s), Other Than Cholera Toxin, Produced by Environmental Non O1 Non O139 Vibrio cholerae

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Cellular & Molecular Immunology 2006年第2期3卷 115-121页

作者： Kohinur Begum Chowdhurv R.Ahsan Mohammad Ansaruzzaman Dilip K.Dutta Qazi s.ahmad Kaisar A.Talukder Department of Microbiology University of DhakaDhaka 1000Bangladesh Department of PharmacyUniversity of Asia PacificHouse 73Road 5ADhanmondi R/ADhaka 1209Bangladesh Department of Microbiology University of DhakaDhaka 1000Bangladesh ICDDR B:International Centre for Health and Population Research BangladeshGPO Box 128Dhaka 1000Bangladesh

A total of 39 Vibrio cholerae non O1 non O139 strains were isolated from surface waters of different parts of Dhaka City, Bangladesh. All these strains showed lack of ctx or zot gene, as demonstrated by the PCR analysis. Eighteen representative strains were tested for enterotoxin production using a rabbit ileal loop model, of which live cells of 8 strains and culture filtrates of 6 strains produced fluid accumulation in ileal loops. However, none of them produced heat stable toxin （sT）, as detected by suckling mouse assay. On the other hand, 15% of isolates produced cytotoxin as detected by the Chinese Hamster Ovary （CHO） cell assay. Fifty times concentrated culture filtrates of the representative strains did not give any precipitin band against the anti-cholera toxin, suggesting the strains produced an enterotoxin, which is antigenically different from known cholera toxin （CT）. Eighty percent of the total isolates were found to be positive for heat labile haemolysin detected by tube method, whereas, 39% were found positive by the Christie-Atkins-Munch-Petersen （CAMP） method. However, 87% of the isolates were positive for haemagglutinin/protease and all of the strains were positive for mannose-sensitive-haemagglutinin assay.

关键词： non O1 non 0139 Vibrio cholerae enterotoxin cytotoxin haemolysin haemaglutinin/protease

Melting heat transfer with radiative effects and homogeneous–heterogeneous reaction in thermally stratified stagnation flow embedded in porous medium

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Journal of Central south University 2018年第11期25卷 2701-2711页

作者： M.JAVED M.FAROOQ s.ahmad Aisha ANJUM Department of Mathematics Riphah International UniversityIslamabad 44000Pakistan

The present article deals with thermally stratified stagnation-point flow saturated in porous medium on surface of variable thickness along with more convincing and reliable surface condition termed as melting heat ***–heterogeneous reaction and radiative effects have been further taken into account to reconnoiterproperties of heat *** heat transfer and phenomenon of homogeneous–heterogeneous reaction have engrossed widespread utilization in purification of metals,welding process,electroslag melting,biochemical systems,catalysis and several industrial *** transformations are utilized to attain a scheme of ordinary differential equations possessing exceedingly nonlinear *** process is employed to develop convergent solutions of the resulting *** regarding velocity,thermal field and concentration distribution for several involved parameters is pivotal *** behaviors of skin friction coefficient and Nusselt number are also *** of the reactants is found to depreciate as a result of strength of both heterogeneous and homogeneous reaction *** existence of melting phenomenon,declining attitude of fluid temperature is observed for higher radiation parameter.

关键词： melting heat transfer porous medium stagnation point variable sheet thickness homogeneous– heterogeneous reaction

Magneto-hydrodynamic flow of squeezed fluid with binary chemical reaction and activation energy

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Journal of Central south University 2019年第5期26卷 1362-1373页

作者： s.ahmad M.FAROOQ N.A.MIR Aisha ANJUM M.JAVED Department of Mathematics and statistics Riphah International University

The present exploration is conducted to describe the motion of viscous fluid embedded in squeezed channel under the applied magnetics *** processes of heat and mass transport incorporate the temperature-dependent binary chemical reaction with modified Arrhenius theory of activation energy function which is not yet disclosed for squeezing flow *** flow,heat and mass regime are exposed to be governed via dimensionless,highly non-linear,ordinary differential equations (ODEs) under no-slip walls boundary conditions.A well-tempered analytical convergent procedure is adopted for the solutions of boundary value problem.A detailed study is accounted through graphs in the form of flow velocity field,temperature and fluid concentration distributions for various emerging parameters of enormous ***-friction,Nusselt and sherwood numbers have been acquired and disclosed through *** results indicate that fluid temperature follows an increasing trend with dominant dimensionless reaction rate σ and activation energy parameter ***,an increment in σ and E parameters is found to decline in fluid *** current study arises numerous engineering and industrial processes including polymer industry,compression and injection shaping,lubrication system,formation of paper sheets,thin fiber,molding of plastic *** the area of chemical engineering,geothermal engineering,cooling of nuclear reacting,nuclear or chemical system,bimolecular reactions,biochemical process and electrically conducting polymeric flows can be controlled by utilizing magnetic *** by such applications,the proposed study has been developed.

关键词： squeezing flow magneto-hydrodynamics (MHD) activation energy binary chemical reaction

Machine learning-enhanced Monte Carlo and subset simulations for advanced risk assessment in transportation infrastructure

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Journal of Mountain science 2024年第2期21卷 690-717页

作者： Furquan ahmad Pijush sAMUI s.s.MIsHRA Department of Civil Engineering National Institute of TechnologyPatna 800006India

The maintenance of safety and dependability in rail and road embankments is of utmost importance in order to facilitate the smooth operation of transportation *** study introduces a comprehensive methodology for soil slope stability evaluation,employing Monte Carlo simulation(MCs)and subset simulation(ss)with the"UPss 3.0 Add-in"in *** on an 11.693-meter embankment with a soil slope(inclination ratio of 2H:1V),the investigation considers earthquake coefficients(kh)and pore water pressure ratios(ru)following Indian zoning *** chance of slope failure showed a considerable increase as the Coefficient of Variation(COV),seismic coefficients(kh),and pore water pressure ratios(ru)experienced an *** ss approach showed exceptional efficacy in calculating odds of failure that are notably *** computational modeling,the study optimized the worst-case scenario using ANFIs-GA,ANFIs-GWO,ANFIs-PsO,and ANFIs-BBO *** ANFIs-PsO model exhibits exceptional accuracy(training R2=0.9011,RMsE=0.0549;testing R2=0.8968,RMsE=0.0615),emerging as the most *** study highlights the significance of conducting thorough risk assessments and offers practical insights into evaluating and improving the stability of soil slopes in transportation *** findings contribute to the enhancement of safety and reliability in real-world situations.

关键词： Monte Carlo simulation subset simulation Machine Learning seismic coefficient

Chaetomium-like fungi causing opportunistic infections in humans:a possible role for extremotolerance

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Fungal Diversity 2016年第1期76卷 11-26页

作者： sarah A.Ahmed Ziauddin Khan Xue-wei Wang Tarek A.A.Moussa Hassan s.Al-Zahrani Omar A.A.lmaghrabi Deanna A.sutton s.ahmad Johannes Z.Groenewald A.Alastruey-Izquierdo Anne van Diepeningen s.B.J.Menken M.J.Najafzadeh Pedro W.Crous Oliver Cornely Axel Hamprecht Maria J.G.T.Vehreschild A.J.Kindo G.sybren de Hoog Faculty of Medical Laboratory sciences University of KhartoumKhartoumSudan CBs-KNAW Fungal Biodiversity Centre P.O.Box 851673508 AD UtrechtThe Netherlands Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdamThe Netherlands Department of Microbiology Faculty of MedicineKuwait UniversityKuwaitKuwait state Key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijingChina Biological sciences Department Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia Botany and Microbiology Department Faculty of ScienceCairo UniversityGizaEgypt Fungus Testing Laboratory Department of PathologyUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA Mycology Reference Laboratory National Centre for MicrobiologyCarlos III Institute of Health(Servicio deMicologíaCentro Nacional de MicrobiologíaInstituto de Salud Carlos III)MadridSpain Department of Parasitology and Mycology Mashhad University of Medical SciencesMashhadIran German Centre for Infection Research(DZIF)at Cologne/Bonn First Department of Internal MedicineUniversity Hospital of CologneCologneGermany Institute for Medical Microbiology Immunology and HygieneUniversity of CologneCologneGermany Department of Microbiology Sri Ramachandra UniversityPorurChennaiIndia Peking University Health science Center Research Center for Medical MycologyBeijingChina sun Yat-sen Memorial Hospital Sun Yat-Sen UniversityGuangzhouChina shanghai Institute of Medical Mycology Changzheng HospitalSecond Military Medical UniversityShanghaiChina 17 Basic Pathology DepartmentFederal University of ParanáStateCuritibaParanáBrazil

Members of the family Chaetomiaceae are ubiquitous ascosporulating fungi commonly,which reside in soil enriched with manure or cellulosic *** role as human pathogens is largely ***,the ability of some species to grow at high temperature enables them to play an important role as opportunistic *** family contains several genera and species that have never been reported to cause human ***,three new species are described;two belong to the genus subramaniula and one represents a Chaetomium *** asteroides was isolated from various sources including eye and skin infections as well as from the natural environment,and *** was isolated from a toe *** anamorphosum was isolated from a kidney transplant patient suffering from fungal *** species described were previously misidentified as Papulaspora *** to the formation of cellular clumps or bulbil-like structures,which are characteristic of *** isolates failed to form sexual fruit bodies and ascospores remained absent,which is an unusual feature for the generally ascosporulating genera Chaetomium and subramaniula;minute conidia from phialides were sometimes observed.

关键词： Chaetomium Desert fungi Keratitis Papulaspora Peritonitis sterile fungi subramaniula