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Calculation of ship motions in steep waves with restoring and Froude-Krylov forces on an adaptive panel mesh with Gauss and analytic integration methods

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Journal of Hydrodynamics 2024年第2期36卷 275-289页

作者： Malwin Wermbter Moustafa abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of TechnologyHamburgGermany

The impulse response method is a frequently used method to calculate ship seakeeping *** this paper,the restoring and Froude-Krylov calculation is conducted with constant evaluation of panel pressures as well as Gauss quadrature and an analytical *** applied panel grid is coarsened by an adaptive algorithm which is based on a normal vector *** comparison of methods is based on grid convergence studies which are followed by a verification of forces with computational fluid dynamics(CFD)results on the fixed duisburg test case in *** with experimental results in head,oblique and following waves show that all integration methods are *** exact integration is numerically sensitive in some *** quadrature is highly accurate;however,the additional effort is not beneficial since the geometrical accuracy has-stronger influence on the force amplitudes than the integration *** grid coarsening reduces the simulation time and is accurate up to a level,where the panel length comes close the *** added resistance at the investigated Froude number of 0.05 shows higher uncertainty levels,this applies to the results of both the numerical methods and model tests.

关键词： Ship hydrodynamics seakeeping impulse response method added resistance wave loads

An extensive analytical and numerical study of the generalized q-deformed Sinh-Gordon equation

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Journal of Ocean Engineering and Science 2024年第3期9卷 232-239页

作者： Khalid K.Ali abdel-Haleem abdel-Aty Mathematics Department Faculty of ScienceAl-Azhar UniversityNasr-CityCairoEgypt Department of Physics College of SciencesUniversity of BishaPO Box 344Bisha 61922Saudi Arabia Physics Department Faculty of ScienceAl-Azhar UniversityAssiut 71524Egypt

In this paper,the q-deformed Sinh-Gordon equation is solved analytically using a new general form based on the extended tanh *** numerical solutions of the equation is obtained using a b-spline finite element ***,we present numerous figures to demonstrate the various solitons propagation *** type of equation has not been previously dealt with in such ways,whether analytical or *** study is very useful in studying several physical systems that have lost their symmetry.

关键词： q-Deformed equation Solitos solutions The extended tanh method Finite element method q-Calculus

Effect of dates on blood glucose and lipid profile among patients with type 2 diabetes

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World Journal of Diabetes 2024年第6期15卷 1079-1085页

作者： Hyder osman Mirghani Internal Medicine University of TabukSaudi ArabiaTabuk 51941TabukSaudi Arabia

Poor fruit and vegetable consumption is one of the 10 major risk factors for *** is a misconception regarding the consumption of dates among patients with *** manuscript assessed the effects of date consumption on fasting and postprandial blood glucose,glycated hemoglobin,total cholesterol,triglycerides,low-density lipoproteins,high-density lipoproteins,and microbial *** literature databases were searched for relevant *** the 595 studies retrieved,24 assessed the effects of dates on glycemic control and ***,the evidence suggests that dates have a lowering effect on blood *** reduce total cholesterol and triglyceride levels and increase high-density lipoprotein *** also promote the abundance of beneficial gut ***,patients with diabetes and dyslipidemia can consume dates to reduce their blood glucose,cholesterol,and triglycerides.

关键词： Dates Lipid profile Blood glucose Diabetes mellitus Microbial contamination

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 37-49页

作者： Mohamed Gamal Gomaa Hamdy Maamoun abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli El-Sayed Ali abdel-Aal abdel-Hakim Taha Kandil Bahaa Ahmed Salah Central Metallurgical Research and Development Institute(CMRDI) 11421 CairoEgypt Chemistry Department Faculty of ScienceHelwan University11795 CairoEgypt Institute on Membrane Technology(CNR-ITM) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

A Comparative Study of Metaheuristic Optimization Algorithms for Solving Real-World Engineering Design Problems

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 1039-1094页

作者： Elif Varol Altay osman Altay Yusuf Ovik Department of Software Engineering Manisa Celal Bayar UniversityManisa45400Turkey

Real-world engineering design problems with complex objective functions under some constraints are relatively difficult problems to *** design problems are widely experienced in many engineering fields,such as industry,automotive,construction,machinery,and interdisciplinary ***,there are established optimization techniques that have shown effectiveness in addressing these types of *** research paper gives a comparative study of the implementation of seventeen new metaheuristic methods in order to optimize twelve distinct engineering design *** algorithms used in the study are listed as:transient search optimization(TSO),equilibrium optimizer(EO),grey wolf optimizer(GWO),moth-flame optimization(MFO),whale optimization algorithm(WOA),slimemould algorithm(SMA),harris hawks optimization(HHO),chimp optimization algorithm(COA),coot optimization algorithm(COOT),multi-verse optimization(MVO),arithmetic optimization algorithm(AOA),aquila optimizer(AO),sine cosine algorithm(SCA),smell agent optimization(SAO),and seagull optimization algorithm(SOA),pelican optimization algorithm(POA),and coati optimization algorithm(CA).As far as we know,there is no comparative analysis of recent and popular methods against the concrete conditions of real-world engineering ***,a remarkable research guideline is presented in the study for researchersworking in the fields of engineering and artificial intelligence,especiallywhen applying the optimization methods that have emerged *** research can rely on this work for a literature search on comparisons of metaheuristic optimization methods in real-world problems under similar conditions.

关键词： Metaheuristic optimization algorithms real-world engineering design problems multidisciplinary design optimization problems

Two-dimensional MOF-based materials:Preparations and applications as electrodes in Li-ion batteries

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Journal of Energy Chemistry 2024年第10期97卷 388-418,I0008页

作者： Narges Nobakht Seyyed Ahmad Etghani Mohammad Hosseini Seyed hamed Aboutalebi Condensed Matter National Laboratory Institute for Research in Fundamental SciencesTehran 19395-5531Iran School of Biological Sciences Institute for Research in Fundamental SciencesTehran 19395-5746Iran BattScout Company London RoadBishopdownSalisbury SP13EnglandUnited Kingdom

Two-dimensional(2D)metal-organic frameworks(MOFs)are rapidly emerging as a unique class of mushrooming family of 2D materials offering distinctive features,such as hierarchical porosity,extensive surface area,easily available active sites,and versatile,adaptable *** promising characteristics have positioned them as highly appealing alternatives for a wide range of applications in energy storage technologies,including lithium ***,the poor conductivity and limited stability of 2D MOFs have limited their real applications in electrochemical energy *** limitations have therefore warranted ongoing research to enhance the performance of 2D *** the significance of 2D MOF-based materials as an emerging class of advanced materials,a multitude of strategy has been devised to address these challenges such as synthesizing 2D conductive MOFs and derivatives along with 2D MOF *** promising approach involves the use of 2D MOF derivatives,including transition metal oxides,which due to their abundant unsatu rated active metal sites and shorter diffusion paths,offer superior electrochemical ***,by combining pristine 2D MOFs with other materials,hybrid 2D MOF materials can be *** hybrids,with their enhanced stability and conductivity,can be directly utilized as active materials in lithium *** the present review,we categorize 2D MOF-based materials into three distinct groups:pristine 2D MOFs,2D MOFderived materials,and 2D MOF hybrid *** synthesis methods for each group,along with their specific applications as electrode materials in lithium-ion batteries,are discussed in *** comprehensive review provides insights into the potential of 2D MOFs while highlighting the opportunities and challenges that are present in this evolving field.

关键词： Li-ion batteries 2D materials 2D metal-organic frameworks Energy storage Synthesis

Comparative CFD-DEM study of flow regimes in spout-fluid beds

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Particuology 2024年第2期85卷 323-334页

作者： hamed Hoorijani Behrad Esgandari Reza Zarghami Rahmat Sotudeh-Gharebagh Navid Mostoufi Multiphase Systems Research Lab School of Chemical EngineeringCollege of EngineeringUniversity of TehranP.O.Box 11155-4563TehranIran Department of Particulate Flow Modelling Johannes Kepler UniversityAltenbergerstr.694040LinzAustria

Spout-fluid beds are unique systems that require thorough study prior to their industrial *** this study,the hydrodynamics of spout-fluid beds were investigated using 3D computational fluid dy-namics coupled with discrete element method(CFD-DEM).Three flow regimes,including jet-in-fluidized bed,spouting-with-aeration,and intermediate/spout-fluidization were studied,and the particle mixing was quantified in these regimes using the Lacey mixing *** results showed that both axial and lateral mixing rates are better in jet-in-fluidized bed and the spouting-with-aeration flow regimes,with the axial mixing being superior to the lateral in all flow *** the diffusivity coefficient revealed that mixing in the jet-in-fluidized bed flow regime is better due to the formation and eruption of bubbles in the ***,the granular temperature was analyzed in all flow regimes,and higher particle velocity fluctuations were observed in the spouting-with-aeration and the jet-in-fluidized bed flow regimes due to the higher spout gas velocity and formation of bubbles in the *** study provides valuable insights into the hydrodynamics of spout-fluid beds in different flow regimes,which can aid in the design and optimization of spout-fluid bed reactors for various industrial applications.

关键词： Flow regime Mixing Diffusivity CFD-DEM Hydrodynamics Spout-fluid bed

Structural Elucidation of the Polymeric Condensed Tannins of Acacia nilotica Subspecies by ^(13)C NMR, MALDI-TOF and TMA as Sources of Bioadhesives

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Journal of Renewable Materials 2024年第7期12卷 1291-1310页

作者： Zeinab osman Antonio Pizzi Bertrand Charrier Institute of Engineering Research and Materials Technology National Center for ResearchP.O.Box 2404KhartoumSudan ENSTIB-LERMAB University of Lorraine27 rue Philippe SeguinEpinal88000France Department of Materials Science and Engineering Institute of Analytical Sciences and Physico-Chemistry for the Environment and Materials-Xylomat(IPREM-UMR5254)University of Pau and the Adour RegionE2S UPPACNRSMont de Marsan40004France

Tannin was extracted from different subspecies of Acacia nilotica,Acacia nilotica nilotica(Ann),Acacia nilotica tomentosa(Ant)and Acacia nilotica adansonii(Ana).The aim was to elucidate their structure and evaluate their reactivity as bioadhesives in the wood *** extracts were prepared by hot water extraction(90°C tem-perature).Their gel time with paraformaldehyde was used atﬁrst to compare their *** tannin contents and the percentage of total polyphenolic materials in different solutions of the extracts spray dried powder were determined by the hide powder *** solutions(47%)were tested by both MALDI ToF,*** thermomechanical analysis(TMA)was performed to evaluate their modulus of elasticity(MOE)at different *** gel times of all the three tannin extracts showed that their reactivity and it was com-parable to other known procyanidin/prodelphinidin tannin extract ***,Ann and Ant showed highest per-cent of total polyphenolic materials at 70%,64%,and 57%,*** 13CNMR spectra showed that the three subspecies of condensed tannins were mainly constituted of procyanidins(PC)and prodelphinidins(PD)in slightly different ***(56.5%PC and 43.4%PD),Ant(57%PC and 43%PD)and Ana(58%PC and 42%PD).MALDI–TOF spectra showed the presence ofﬂavonoid monomers,and oligomers some of which linked to short carbohydrates monomers or *** revealed that the three types of tannins had high MOE at their initial pH(5).

关键词： Acacia nilotica condensed tannins procyanidins prodelphinidins 13C NMR MALDI-ToF

Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： abdel-Aal Mabdel-Karim Mohamed MHamdy Adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage Magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt