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Nanomanufacturing and Metrology 2021年第4期4卷 226-236页

作者： hammad younes Haiping Hong G.P.Peterson Department of Electrical Engineering South Dakota School of Mines and TechnologySouth DakotaRapid City 57701USA Department of Mechanical Engineering Khalifa University of Science and TechnologyMasdar InstitutePO Box 54224Abu DhabiUAE Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

A better understanding of the bonding and aggregation processes occurring between carbon nanomaterials and metal oxide particles in aqueous solutions is important in the development of novel nanosolids for applications in the areas of sensor development,highly conductive paint,nanotube alignment,polymer composites,Li-ion batteries,and many other *** current investigation reviews these processes and presents a detailed description of the aggregation processes occurring between carbon nanomaterials and metal oxide particles(metals)in various aqueous *** results indicate that the charge attraction between the particles results in a strong homogeneous bonding that occurs within the aqueous solution and for the first time demonstrate and describe the aggregation process of these *** relative importance of many parameters that impact the aggregation process is identified and discussed,and guidelines for controlling the aggregation process are *** is a simple and cost-effective process to manufacture a novel nano-solid based on carbon nanomaterial and metal *** addition,the process is easy to scale up and *** methodology could lead to many significant applications as well as commercialization.

关键词： Nanosolid Aggregation technique Nanofluids Charge attraction Nanoparticles Nanomanufacturing

Manufacturable Novel Nanogrease with Superb Physical Properties

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Nanomanufacturing and Metrology 2021年第4期4卷 289-297页

作者： hammad younes Ding Lou Haiping Hong Huahui Chen Hongtao Liu Yinhuai Qiang Department of Electrical Engineering South Dakota School of Mines and TechnologyRapid CitySD 57701USA Department of Material Science and Engineering School of Mechanical and Electrical EngineeringChina University of Mining and TechnologyBeijing 100083China School of Material Science and Engineering China University of Mining and TechnologyXuzhou 221166China

High-performance nanogrease manufactured from carbon nanomaterials is observed to be stable and homogeneous and have superb physical properties,such as thermal and electrical conductivities,compared with current commercial greases made of lithium,calcium,and *** the first time,carbon nanomaterials have been observed to disperse well as the sole thickeners in oil systems,e.g.,polyalphaolefin and polyester(ROYCO),without the aid of any chemical ***-dimensional percolation network structures that exist among carbon nanomaterials are easily scalable,which can be attributed to the intermolecular van der Waals ***,the introduction of hydrogen bonding in any form to grease significantly increases its thermal and electrical conductivities and substantially reduces the weight percentage of carbon nanomaterials needed to fabricate stable *** example,loading of only 1.4 wt%hydroxyl-functionalized multiwalled carbon nanotube(MWNT-OH)with Krytox XHT750 oil leads to a 37.8%increase in thermal ***,75%glycerol,25% water,and 4.5 wt% MWNT-OH yielded the lowest electrical resistivity of 10.0 Ω *** finding can be extended to hydrogen bonding materials with functional groups,such as OH,COOH,F,and *** nanogrease reported in this study has been manufactured using the three-roll mill method,which is an easy and cost-effective method,as the loading weight percentage of carbon nanomaterials to fabricate stable grease decreases from 12 wt% to 3-4 wt%.Furthermore,the process is easily scalable,reproduced,and *** novel high-performance nanogrease has a high commercial value and numerous applications and could replace current commercial greases.

关键词： Nanogrease Three-dimensional network percolation structure Carbon nanomaterial Van der Waals forces Hydrogen bonding Thermal conductivity Electrical conductivity

Decoding molecular mechanisms:brain aging and Alzheimer's disease

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Neural Regeneration Research 2025年第8期20卷 2279-2299页

作者： Mahnoor Hayat Rafay Ali Syed hammad Qaiser Mohammad Uzair Khalid Al-Regaiey Roaa Khallaf Lubna Abdullah Mohammed Albassam Imdad Kaleem Xueyi Wang Ran Wang Mehwish SBhatti Shahid Bashir Atta-ur-Rahman School of Applied Biosciences(ASAB) National University of Sciences and Technology(NUST)IslamabadPakistan Department of Biotechnology Quaid-i-Azam UniversityIslamabadPakistan Department of Biological Sciences Faculty of Basic&Applied SciencesInternational Islamic University Islamabad(IIUI)IslamabadPakistan Department of Bioengineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia Department of Physiology College of MedicineKing Saud UniversityRiyadhSaudi Arabia Department of Neurology Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Mental Health Neuroscience CenterKing Fahad Specialist HospitalDammamSaudi Arabia Department of Biosciences Commission on Science and Technology for Sustainable Development in the South(COMSATS University)IslamabadPakistan Department of Psychiatry The First Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Mental Health Institute of Hebei Medical University ShijiazhuangHebei ProvinceChina Department of Neurobiology and Behavior University of CaliforniaIrvineCAUSA Neuroscience Center King Fahad Specialist Hospital DammamDammamSaudi Arabia

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for *** aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's *** these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging *** these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect *** review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

关键词： Alzheimer’s disease brain aging cognitive health dementia molecular mechanisms neuronal activity neuroplasticity neurotransmission

Variable viscosity effects on the flow of MHD hybrid nanofluid containing dust particles over a needle with Hall current——a Xue model exploration

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Communications in Theoretical Physics 2022年第5期74卷 121-131页

作者： Muhammad Ramzan hammad Alotaibi Department of Computer Science Bahria UniversityIslamabad44000Pakistan Department of Mathematics College of ScienceTaif UniversityPOBox 11099Taif 21944Saudi Arabia

This study scrutinizes the flow of engine oil-based suspended carbon nanotubes magnetohydrodynamics(MHD)hybrid nanofluid with dust particles over a thin moving needle following the Xue *** analysis also incorporates the effects of variable viscosity with Hall *** heat transfer analysis,the effects of the Cattaneo–Christov theory and heat generation/absorption with thermal slip are integrated into the temperature *** Tiwari–Das nanofluid model is used to develop the envisioned mathematical *** similarity transformation,the governing equations for the flow are translated into ordinary differential *** bvp4c method based on Runge–Kutta is used,along with a shooting *** are used to examine and depict the consequences of significant parameters on involved *** results revealed that the temperature of the fluid and boundary layer thickness is diminished as the solid volume fraction is ***,with an enhancement in the variable viscosity parameter,the velocity distribution becomes more *** results are substantiated by assessing them with an available study.

关键词： hybrid nanofluid dusty fluid variable viscosity Cattaneo-Christov heat flux model Hall current

Offshore Carbonate Facies Characterization and Reservoir Quality of Miocene Rocks in the Southern Margin of South China Sea

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1547-1561页

作者： hammad Tariq JANJUHAH Abubaker ALANSARI Department of Geology Shaheed Benazir Bhutto UniversitySheringal Upper DirKPKPakistan Department of Geology American University of BeirutRiad El-SolhBeirut11072020Lebanon Department of Geosciences University Technology PETRONAS32610PerakMalaysia

Carbonate rocks are important hydrocarbon reservoirs around the globe and in Southeast Asia a key one,particularly,is the Central Luconia *** the internal characteristics,distribution,geometry and lateral extent of these rocks is essential for exploration and production *** work on Miocene carbonate reservoir facies,north of Bintulu,offshore Sarawak includes qualitative and quantitative analysis of photomicrographs and reservoir quality,considering especially ***,these carbonates are known as Cycles IV and V and are represented by eight major facies types(F-1 to F-8).They comprise:coated grain packstone(F-1)(av.Ф=3%,***=0.5 m D)(av=Average;?=total porosity,and Kh=permeability);massive coral lime grainstone(F-2)(av.Ф=14.7%,***=6 m D);oncolite lime grain-dominated packstone(F-3)(av.Ф=10%,***=4 m D);skeletal lime/dolo-packstone(F-4)(av.Ф=15%,***=4.6 m D);coral(platy)lime mud-dominated packstone(F-5)(av.Ф=4%,***=0.5 m D);coral(branching)lime-dominated pack-grainstone(F-6)(av.Ф=15%,***=1 m D);cross-bedded skeletal lime packstone(F-7)(av.Ф=20%,***=2 m D);and bioturbated carbonate mudstone/chalk(F-8)(av.Ф=8%,***=0.8 m D).Study of thin sections reveals that red algae,foraminifera,and corals are the dominant fossil components with a minor admixture of skeletal fragments of echinoderms,bivalves,bryozoans,and green *** parameters,e.g.,facies characterization,petrography,porosity–permeability value,and microporosity value were utilized to obtain a reliable reservoir *** microporosity value was quantified using digital image analysis software and is significant for recognition of good reservoir *** of the presence of microporosity against the total porosity in the carbonate rocks has improved the correlation coefficient(R2)value,which has increased from 0.51 to 0.82.

关键词： carbonates petrography grain types porosity-permeability hydrocarbons microporosity offshore Sarawak

Electrical Properties of Li-doped P-type ZnO Ceramics

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Journal of Materials Science & Technology 2009年第3期25卷 314-318页

作者： A.H. Salama F.F. hammad Physical Chemistry Department National Research Center Inorganic Chemistry Department National Research Center

Li-doped p-type ZnO ceramics were prepared by conventional methods according to the chemical formula Zn1-xLixO2 where x=0.5, 1.0, 1.5 and 2.0 mole fraction, respectively. The crystal structures of the prepared samples were studied by X-ray diffraction analysis. The dielectric properties （including dielectric constant ε′ and dielectric loss ε″） and dc-electrical conductivity [σ（Ω^-***^-1）] were investigated. The dielectric constant ε′ was sharply decreased at the low frequency range and independent on frequency at high frequency range. Otherwise, the dielectric loss ε″ varied with frequency and showed absorption peak located from 200 Hz to 4 kHz and moved to higher frequency as the concentration of Li＋ doped increased. It was found that dcelectrical conductivity logσ varied from -9 to -5 and the energy gap width were calculated by using Arrhenius equation. The p-type conductivity of Li-doped ZnO may be attributed to the formation of a Lizn-Lii donor complex, which is limited by reducing the amount of Lii.

关键词： P-type ZnO ceramics Dielectric constant Dielectric loss dc-conductivity

New topological and non-topological unidirectional-wave solutions for the modifie d-mixe d KdV equation and bidirectional-waves solutions for the Benjamin Ono equation using recent techniques

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Journal of Ocean Engineering and Science 2022年第2期7卷 163-169页

作者： Marwan Alquran Mohammed Ali hammad Jadallah Department of Mathematics and Statistics Jordan University of Science&TechnologyIrbid 22110Jordan

In this paper,new explicit unidirectional wave solutions for the modified-mixed KdV equation and bidi-rectional waves for the Benjamin Ono equation are *** extension of the rational sine-cosine and sinh-cosh methods are *** addition,an extension of the recent polynomial function method is applied as *** types of topological and non-topological soliton solutions are extracted to the proposed models and categorized by providing 2D and 3D ***,some physical properties of the new bidirectional waves solutions to the Benjamin Ono model are discussed.

关键词： Single-wave solutions Two-waves solutions Extended rational sine-cosine method Extended rational sinh-cosh method Polynomial-function method

A review of friction models in interacting joints for durability design

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Friction 2017年第1期5卷 1-22页

作者： Zulfiqar A.KHAN Vivek CHACKO hammad NAZIR NanoCorr Energy & Modelling(NCEM)Research Department of Design & Engineering Bournemouth University Bournemouth United Kingdom

This paper presents a comprehensive review of friction modelling to provide an understanding of design for durability within interacting *** is a complex phenomenon and occurs at the interface of two components in relative *** the last several decades,the effects of friction and its modelling techniques have been of significant interests in terms of industrial *** is however a need to develop a unified mathematical model for friction to inform design for durability within the context of varying operational *** dynamic mechanisms model for the design of control systems has not incorporated friction phenomena due to non-linearity ***,the tribological performance concurrently with the joint dynamics of a manipulator joint applied in hazardous environments needs to be fully *** the dynamics and impact models used in mechanical joints with clearance have also been *** inclusion of reliability and durability during the design phase is very important for manipulators which are deployed in harsh environmental and operational *** revolute joint is susceptible to failures such as in heavy manipulators these revolute joints can be represented by lubricated conformal sliding *** presence of pollutants such as debris and corrosive constituents has the potential to alter the contacting surfaces,would in turn affect the performance of revolute joints,and puts both reliability and durability of the systems at greater risks of *** literature is identified and a review on the latest developments of the science of friction modelling is presented *** review is based on a large volume of *** in the relevant field have been identified to capitalise on for future ***,this review will bring significant benefits to researchers,academics and industry professionals.

关键词： friction dynamics joint clearance numerical models impact durability

Influences of Ag and Au Additions on Structure and Tensile Strength of Sn-5Sb Lead Free Solder Alloy

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Journal of Materials Science & Technology 2008年第6期24卷 921-925页

作者： A.A.El-Daly Y.Swilem A.E.hammad Physics Department Faculty of ScienceZagazig UniversityZagazigEgypt

It is important, for electronic application, to decrease the melting point of Sn-5Sb solder alloy because it is relatively high as compared with the most popular eutectic Pb-Sn solder alloy. Adding Au or Ag can decrease the onset melting temperature （233℃） of this alloy to 203,5℃ and 216℃, respectively. The results indicate that the Sn-5Sb-i.5Au alloy has very good ultimate tensile strength （UTS）, ductility, and fusion heat, which are better than both those of the *** and Sn-5Sb alloys. The formation of intermetallic compounds （IMCs） AuSn4 and Ag3Sn enhanced the SbSn precipitates in the solidification microstructure microstructure stability, while retained the formation of thus significantly improved the strength and ductility For all alloys, both UTS and yield stress （σy） increase with increasing strain rate and decrease with increasing temperature in tensile tests, but changes of ductility are generally small with inconsistent trends.

关键词： Sn-Sb solder Lead-free solder Melting temperature Tensile strength

Analysis and Characterization of Pore System and Grain Sizes of Carbonate Rocks from Southern Lebanon

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Journal of Earth Science 2023年第1期34卷 101-121页

作者： Mohamed K.Salah hammad Tariq Janjuhah Josep Sanjuan Department of Geology American University of BeirutRiad El SolhBeirut11072020Lebanon Department of Geology Shaheed Benazir Bhutto UniversitySheringal KP10850Pakistan Department of Earth and Ocean Dynamics Faculty of Earth SciencesUniversity of BarcelonaBarcelona08028Spain

Carbonate rocks are common in many parts of the world, including the Eastern Mediterranean, where they host significant groundwater supplies and are widely used as building and ornamental stones. The porosity of carbonate rocks plays a critical role in fluid storage and retrieval. The pore structure connectivity, in particular, controls many properties of geological formations, as well as the relationships between the properties of individual minerals and the bulk properties of the rock. To study the relationships between porosity, rock properties, pore structure, pore size, and their impact on reservoir characteristics, 46 carbonate rock samples were collected from four stratigraphic sections exposed near Sidon, South Lebanon. The studied carbonate rocks are related to marine deposits of different ages(e.g., Upper Cretaceous, Eocene, and Upper Miocene). In order to understand the pore connectivity, the MICP(mercury injection capillary pressure) technique was conducted on ten representative samples. Results from the SEM analysis indicate the dominance of very fine and fine pore sizes, with various categories ranging in diameter from 0.1 to10 μm. The MICP data revealed that the pore throat radii vary widely from 0.001 to 1.4 μm, and that all samples are dominated by micropore throats. The grain size analysis indicated that the studied rocks have significant amounts of silt-and clay-size grains with respect to the coarser ‘sand-size’ particles, suggesting a high proportion of microporosity. Obtained results, such as the poorly-sorted nature of grains, high microporosity, and the high percentage of micropore throats, justify the observed low mean hydraulic radius, the high entry pressure, and the very low permeability of the studied samples. These results suggest that the carbonate rocks near Sidon(south of Lebanon) are possibly classified as non-reservoir facies.

关键词： petrophysics mercury injection capillary pressure(MICP) micrite microtexture microporosity platform carbonates southern Lebanon