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Journal of materials Science & Technology 2016年第6期32卷 573-582页

作者： m.hassan Ahmed S.Afify J.m.Tulliani Department of Applied Science and Technology Politecnico di Torino

This work investigated the sensitivity toward humidity, NO2 and H2 of ZnO modified sepiolite （Si12mg8O30（OH）4.（H2O）4.8H2O）. To this aim, sepiolite powder was first modified by leaching magnesium ions in HCI then by precipitating nano-sized Zn-based compounds under basic conditions. A subse- quent thermal treatment at 550 ℃ for 1 h was performed. The powders were characterized by X-ray diffraction （XRD）, specific surface area measurements, thermogravimetric and differential thermal anal- ysis and field emission scanning electron microscopy, as well as high resolution transmission electron microscopy. The XRD patterns showed that all leached heat treated samples were made of anhydrous sepiolite and of ZnO. Sensors were then obtained by screen printing these materials onto commercial alumina substrates with Pt electrodes. All the investigated compositions were capable of detecting NO2 down to ppm level and 20 ppm H2, at an optimal working temperature of 300°C. These detection limits are in line with the current best results reported in literature.

关键词： Clay minerals Gas sensor Sensitivity Hydrogen sensor Nitrogen Oxide

A new technique for fault diagnosis in transformer insulating oil based on infrared spectroscopy measurements

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High Voltage 2024年第2期9卷 319-335页

作者： mohamed m.F.Darwish mohamed H.A.hassan Nagat m.k.Abdel-Gawad matti Lehtonen Diaa-Eldin A.mansour Department of Electrical Engineering Faculty of Engineering at ShoubraBenha UniversityCairoEgypt Department of Electrical Engineering and Automation School of Electrical EngineeringAalto UniversityEspooFinland Department of Electrical Power Engineering Egypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityEgypt Department of Electrical Power and machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Condition monitoring of the insulating system within power transformers has a massive importance according to the electrical *** gas analysis(DGA)is frequently used for this ***,DGA lacks the necessary level of accuracy to identify all equipment faults,particularly in their initial stages of ***,it does not have the capability for real-time monitoring and relies on manual sampling and laboratory testing,causing potential delays in fault ***,the interpretation of DGA data necessitates specialised expertise,which may pose difficulties for smaller entities that have limited access to ***,the contribution of this research is to use infrared spectroscopy measurements as a new effective technique substituting the DGA method for fault diagnosis in insulating *** inception faults that were considered in this study were the electrical fault(discharges of high energy)and the thermal fault(300°Cmperatureed especially for serving the simulation processes inside the laboratory for both types of inception ***,six samples of pure paraffinic mineral oil were taken to be degraded in the *** that,all of them besides another sample that were not subjected to any kind of faults were taken to be examined by Fourier transform infrared(FTIR)spectroscopy to obtain an overview of the oil's behaviour in each fault *** that,the FTIR analysis was initially verified utilising the DGA ***,for further affirmation,the dielectric dissipation factor(DDF)for all samples was *** the final analysis,the verification tests provide experimental evidence about the outperformance of this new optical technique in detecting the transformer's inception faults in addition to proving its potential for being a superior alternative to the well-known traditional diagnostic techniques.

关键词： fault diagnosis spectroscopy

Dye removal using some surface modified silicate minerals

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International Journal of mining Science and Technology 2014年第2期24卷 183-189页

作者： Selim k.A. Youssef m.A. Abd El-Rahiem F.H. hassan m.S. Central metallurgical Research and Development Institute

The objective of this work is to study the efficiency of some surface modified phyllosilicate minerals （bentonite and glauconite） in the removal of dyes from textile waste water. It is found that complete dye removal was achieved by using 10-25g modified glauconite from solutions having a dye concentration of 10-50 mg/L. Adsorption data were modeled using Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherms. Adsorption capacities and optimum adsorption isotherms were predicted by linear regression method. The analysis of experimental isotherms showed that Langmuir isotherm reasonably fit the experimental data in the studied concentration range for the adsorption of dye onto glauconite mineral surface where Freundlich isotherm fit the experimental data for the adsorption of dve onto bentonite mineral surface.

关键词： Glauconite Bentonite Dye removal modified silicate minerals Adsorption

Scattering of water waves by a wave energy device consisting of a pair of co-axial cylinders in a uniform water having finite channel width

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Journal of Ocean Engineering and Science 2021年第3期6卷 276-284页

作者： P.Borah m.hassan Department of mathematics North Eastern Regional Institute of Science and TechnologyItanagarArunachal Pradesh 791109India

We consider a device which consists of a floating structure over a cylindrical plate placed at a finite height from the impermeable ocean *** paper developes the interaction of linear water waves with such a *** whole fluid domain is divided into a number of sub-domains and boundary value problems are formulated for each identified *** channel multipoles,separation of variables and matched eigenfunction expansion methods allow us to solve boundary value problems for the diffracted velocity potentials in each *** investigate the wave forces exerted on the proposed ***,the effects of the various parameters,e.g.,drafts,radii,the gap between the cylinders and mainly channel width of the device on the wave forces exerted by the cylinders are presented *** observe a small oscillation nature near the peak value of the exciting force for the particular value of channel width w=*** peak value of the exciting forces occurs near the wavenumber kr 1=1.0 for different width of the channel *** obtained results are compared with some available results,and it shows a good agreement between the obtained and available results.

关键词： Water waves Exciting force Channel multipoles Channel width Wavenumber,2000 mSC 76B07 76B15.

Towards superior permeability and antifouling performance of sulfonated polyethersulfone ultrafiltration membranes modified with sulfopropyl methacrylate functionalized SBA-15

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Chinese Journal of Chemical Engineering 2023年第1期53卷 89-100页

作者： Eid H.Alosaimi Ibrahim Hotan Alsohaimi hassan m.A.hassan Qiao Chen Saad melhi Ayman Abdelaziz Younes Department of Chemistry College of ScienceUniversity of BishaBisha 61922Saudi Arabia Chemistry Department College of ScienceJouf UniversitySakaka 2014Saudi Arabia Chemistry Department School of Life SciencesSussex UniversityBrighton BN19QJUK

A non-solvent induced phase separation(NIPS)process was used to fabricate a series of sulfonated polyethersulfone(SPES)membranes blending with different concentrations of SBA-15-g-PSPA with the applications in the ultrafiltration(UF)***-15 was modified with 3-methacrylate-propyltrime thoxysilane(mPS)to form *** was further modified with the charge tailorable polymer chains by reacting with 3-sulfopropyl methacrylate potassium *** nanoparticles were uniformly dispersed and finger-like channels were developed within the *** adding of surface modified SBA-15-g-PSPA nanoparticles has significantly improved membrane water permeability,hydrophilicity,and antifouling *** pure water fluxes of the composite SPES membranes were significantly higher than the pristine SPES *** the membrane containing 5%(mass)of SBA-15-g-PSPA(mSSPA5),the pure water flux was increased dramatically to 402.15 Lm^(-2)·h^(-1),which is ~1.5 times that of mSSPA0(268.0 Lm^(-2)·h^(-1)).The high flux rate was achieved with 3%(mass)of SBA-15 nanoparticles with retained high rejection ratio 98%for natural organic *** results indicate that the fashioned composite membrane comprising SBA-15-g-PSPA nanoparticles have a promising future in ultrafiltration applications.

关键词： Ultrafiltration membrane Antifouling Permeability SBA-15 NOm foulant

Liquation cracking in the heat-affected zone of IN939 superalloy tungsten inert gas weldments

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International Journal of minerals,metallurgy and materials 2020年第6期27卷 764-773页

作者： hassan kazempour-Liasi mohammad Tajally hassan Abdollah-Pour Faculty of materials and metallurgical Engineering Semnan UniversitySemnanIran

The main aim of this study was to investigate liquation cracking in the heat-affected zone(HAZ)of the IN939 superalloy upon tungsten inert gas welding.A solid solution and age-hardenable filler metals were further *** the pre-weld heat-treated samples,upon solving the secondaryγ′particles in the matrix,primaryγ′particles in the base metal grew to"ogdoadically diced cubes"of about 2μm in side *** pre-weld heat treatment reduced the hardness of the base metal to about HV *** studies using optical and fieldemission scanning electron microscopy revealed that the IN939 alloy was susceptible to liquation cracking in the *** constitutional melting of the secondary,eutectic,and Zr-rich phases promoted the liquation cracking in the *** microstructure of the weld fusion zones showed the presence of fine spheroidalγ′particles with sizes of about 0.2μm after the post-weld heat treatment,which increased the hardness of the weld pools to about HV 350 and 380 for the Hastelloy X and IN718 filler metals,*** of a suitable solid solution filler metal could partially reduce the liquation cracking in the HAZ of IN939 alloy.

关键词： superalloy tungsten inert gas weld heat-affected zone liquation cracking

Static spherically symmetric wormholes in f(Q,T)gravity

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Chinese Physics C 2022年第11期46卷 275-290页

作者： moreshwar Tayde Zinnat hassan P.k.Sahoo Sashideep Gutti Department of mathematics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India Department of Physics Birla Institute of Technology and Science-PilaniHyderabad CampusHyderabad-500078India

In this study,we obtain wormhole solutions in the recently proposed extension of symmetric teleparallel gravity,known as f(Q,T)***,the gravitational Lagrangian L is defined by an arbitrary function f of Q and T,where Q is a non-metricity scalar,and T is the trace of the energy-momentum *** this study,we obtain field equations for a static spherically symmetric wormhole metric in the context of general f(Q,T)*** study the wormhole solutions using(ⅰ)a linear equation of state and(ⅱ)an anisotropy *** adopt two different forms of f(Q,T),(a)linear f(Q,T)=αQ+βT and(b)non-linear f(Q,T)=Q+λQ^(2)+ηT,to investigate these *** investigate various energy conditions to search for preservation and violation among the obtained solutions and find that the null energy condition is violated in both cases of our assumed forms of f(Q,T).Finally,we perform a stability analysis using the Tolman-Oppenheimer-Volkov equation.

关键词： wormhole EoS energy conditions stability analysis f(Q,T)gravity

Oscillation Criteria of Second Order Half Linear Delay Dynamic Equations on Time Scales

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Acta mathematicae Applicatae Sinica 2017年第1期33卷 83-92页

作者： H.A. AGWO A.m.m. kHODIER HEBA A. hassan Department of mathematics Faculty of Education Ain Shams University 11757 beside Tabary school RoxyCairo Egypt

In this paper, we establish some new oscillation criteria for a non autonomous second order delay dynamic equation （r（t）g（x△（t）））△＋p（t）f（x（τ（t）））=0 on a time scale T. Oscillation behavior of this equation is not studied before. Our results not only apply on differential equations when T=R, difference equations when T=N but can be applied on different types of time scales such as when T=N for q〉1 and also improve most previous results. Finally, we give some examples to illustrate our main results.

关键词： time scales oscillation second order delay dynamic equations generalized Riccati technique generalized exponential function

Determining the mechanism behind yoga’s effects on preventing the symptoms of Alzheimer’s disease

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Neural Regeneration Research 2020年第2期15卷 261-262页

作者： Adithy hassan meghan Robinson Stephanie m. Willerth Division of medical Sciences 3800 Finnerty RoadUniversity of VictoriaVictoriaBritish ColumbiaCanada The Vancouver Prostate Centre VancouverBritish ColumbiaCanada Department of mechanical Engineering University of VictoriaVictoriaBritish ColumbiaCanadaCentre for Biomedical ResearchUniversity of VictoriaVictoriaBritish ColumbiaCanadaInternational Collaboration on Repair DiscoveriesUniversity of British ColumbiaVancouverBritish ColumbiaCanada

Background on the relationship between meditation/yoga practice and its effect on Alzheimer's disease (AD): Dementia refers to a variety of conditions that affect the normal function of the brain, leading to symptoms like memory loss, issues with problem solving, difficulty in processing thoughts and disordered language (mckhann et al., 2011).

关键词： effects yoga Alzheimer's disease

Tight Rock Wettability and Its Relationship to Other Petrophysical Properties： A montney Case Study

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Journal of Earth Science 2017年第2期28卷 381-390页

作者： Ali Javaheri hassan Dehghanpour James m.Wood University of Alberta Edmonton AB T6G 2R3 Canada Encana Corporation Calgary AB T2P 2S5 Canada

Understanding and modelling the wettability of tight rocks is essential for designing fracturing and treatment fluids. In this paper, we measure and analyze spontaneous imbibition of water and oil into five twin core plugs drilled from the cores of a well drilled in the montney Formation, an unconventional oil and gas play in the Western Canadian Sedimentary Basin. We characterize the samples by measuring the mineralogy using XRD（x-ray diffraction）, total organic carbon content, porosity, and permeability. Interestingly, the equilibrated water uptake of the five samples is similar, while, their oil uptake increases by increasing the core porosity and permeability. We define two wettability indices for the oil phase based on the slope and equilibrium values of water and oil imbibition curves. Both indices increase by increasing porosity and permeability, with the slope affinity index showing a stronger correlation. This observation suggests that part of the pore network has a stronger affinity to oil than to water. We also observe that the two indices decrease by increasing neutron porosity and gamma ray parameters measured by wireline logging tools. The samples with higher gamma ray and neutron porosity are expected to have greater clay content, and thus less effective porosity and permeability.

关键词： spontaneous imbibition wettability petrophysics gamma ray log