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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO S.el-BORGI School of mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPm).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(mmS)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPm for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPm) method of multiple scales(mmS) dispersion phase velocity

magneto-Photo-Thermoelastic Excitation Rotating Semiconductor medium Based on moisture Diffusivity

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Computer modeling in Engineering & Sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.m.S.mahdy Alaa A.el-Bary E.S.elidy Department of mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia Department of mathematics and Statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for Science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

Vaccination effect on a stochastic epidemic model with healing and relapse

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International Journal of Biomathematics 2024年第1期17卷 29-59页

作者： m.m.Abdeslami L.Basri m.el Fatini I.Sekkak R.Taki Laboratory of Partial Differential Equations Spectral Algebra and Geometry Department of mathematics Faculty of Sciences Ibn Tofail UniversityBP 133KénitraMorocco Centre de Recherche en Sante Publique montréal(Québec)H3N 1X9 Canada Departement de Medecine Sociale et Preventive Ecole de SantéPublique de I'Universitéde Montreal 101Avenue du ParcMontréal(Quebec)H3N 1X9Canada EST Sidi Bennour Chouaib Doukkali UniversityEl JadidaMorocco

In this work,we consider a stochastic epidemic model with vaccination,healing and *** prove the existence and the uniqueness of the positive *** establish sufficient conditions for the extinction and the persistence in mean of the stochastic ***,we also establish sufficient conditions for the existence of ergodic stationary distribution to the model,which reveals that the infectious disease will *** graphical illustrations of the approximate solutions of the stochastic epidemic model have been performed.

关键词： Stochastic epidemic model with relapse and healing vaccination extinction persistence in mean markov semigroup stationary distribution

Evaluation of the nutritional value of Artemia nauplii for European seabass(Dicentrarchus labrax L.)larvae

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Aquaculture and Fisheries 2024年第1期9卷 78-84页

作者： Alaa A.el-Dahhar Rashwan S.Rashwan samy Y.el-Zaeem Shaimaa A.Shahin mona m.mourad mohammed F.el Basuini Animal and Fish Production Department Faculty of Agriculture-Saba BashaAlexandria UniversityAlexandria21526Egypt National Institute of Oceanography and Fisheries(NIOF) Cairo11562Egypt Department of Animal Production Faculty of AgricultureTanta UniversityTanta31527Egypt Faculty of Desert Agriculture King Salman International UniversitySouth Sinai46618Egypt

Adapted European seabass(Dicentrarchus labrax L.)larvae at 25 days post-hatching(dph)with a primary weight and length of 23 mg and 9.92 mm,start the weaning up to 46 dph using the weaning micro-diet(54%crude protein from fish meal,powder milk,and poultry egg)concurrently with Artemia enriched with fortification emulsions(0.6 g/L)of DHA selco®as a control group(DHAS)or Fish oil+20%Vitamin C(FOVC),or Fish oil+20%Vitamin E(FOVE),or Fish oil+10%Vit.C+10%Vit.E(FOCE),or Fish oil only(FO).At 46 dph,groups of larvae fed enriched Artemia with DHAS and FOVE exhibited the highest final body weight,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the lowest feed conversion ***,larvae in FOVC displayed the lowest final body weight,total length,weight gain,average daily gain,specific growth rate,feed intake,protein efficiency ratio,and survival%as well as the highest feed conversion *** histological assessment exhibited no pathological alteration as well as an improvement in the structure with DHAS,FOVE,FOVC,and FOCE co-additives compared to *** peroxidase enzyme(GPx)recorded the highest rates(Pmia supplemented with DHAS and FOVE followed by FOCE and *** the lowest record for GPx activity was noted in the FO *** conclusion,Using augmented Artemia nauplii with fish oil+vitamin E in single or in companion with vitamin C as cheap antioxidants support *** larval growth,survival,and antioxidant efficacy during the critical weaning period.

关键词： European seabass Gastrointestinal histology Antioxidants Vitamin C Vitamin E DHA

Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt

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Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa S ABO HATAB Yassin m AL-SODANY Kamal H SHALTOUT Soliman A HAROUN mohamed m el-KHALAFY Botany and microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes morocco, mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic sp

关键词： endemism phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)

Natural Convection of a Power-Law Nanofluid in a Square Cavity with a Vertical Fin

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Fluid Dynamics & materials Processing 2024年第9期20卷 2091-2108页

作者： Amira m’hadbi mohammed el Ganaoui Haïkel Ben Hamed Amenallah Guizani Khalid Chtaibi LERmAB Department of Transition and Energy Efficiency ProfessionsIUT H Poincaréde LongwyUniversity of LorraineLongwy54400France LPT Center for Energy Research and Technologies(Borj Cedria2084)University of Tunis El ManarTunis1068Tunisia LTI Department of Mechanical Engineering and ProductionIUTUniversity of Picardie Jules-VerneAmiens80025France

The behavior of non-Newtonian power-law nanofluids under free convection heat transfer conditions in a cooled square enclosure equipped with a heated fin is investigated *** particular,the impact of nanofluids,composed of water and Al_(2)O_(3),TiO_(2),and Cu nanoparticles,on heat transfer enhancement is *** aim of this research is also to analyze the influence of different parameters,including the Rayleigh number(Ra=10^(4)-10^(6)),nanoparticle volume fraction(φ=0%-20%),non-Newtonian power-law indexes(n=0.6-1.4),and fin dimensions(Ar=0.3,0.5,and 0.7).Streamlines and isotherms are used to depict flow and related heat transfer *** indicate that thermal performance improves with increasing Rayleigh number,regardless of the nanoparticle type or nanofluid rheological *** suggests that the buoyancy force has a significant impact on heat transfer,particularly near the heat *** Nusselt number is more sensitive to variations in Cu nanoparticle volume fractions compared to Al₂O₃and TiO₂.moreover,the average Nusselt numbers for power-law nanofluids with n1)are greater(smaller)than for Newtonian fluids due to the decrease(increase)in viscosity with increasing(decreasing)shear rate,at the same values of Rayleigh number Ra owing to the amplification(attenuation)of the convective ***,the most substantial enhancement is observed with Cu-water shear-thinning nanofluid,where the Nusselt number increases by 136%when changing from Newtonian to shear thinning behavior and by 154.9%when adding 16%nanoparticle volume ***,an even larger increase of 57%in the average Nusselt number is obtained on increasing the fin length from 0.3 to 0.7.

关键词： Heat transfer nanofluid non-Newtonian fluid natural convection

Novel Sustainable Cellulose Acetate Based Biosensor for Glucose Detection

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Journal of Renewable materials 2024年第2期12卷 369-380页

作者： m.F.elkady E.m.el-Sayed mahmoud samy Omneya A.Koriem H.Shokry Hassan Chemical and Petrochemical Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt Fabrication Technology Research Department Advanced Technology and New Materials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt Department of Public Works Engineering Faculty of EngineeringMansoura UniversityMansoura35516Egypt Environmental Engineering Department Egypt-Japan University of Science and TechnologyNew Borg El-ArabAlexandriaEgypt electronic materials Research Department Advanced Technology and NewMaterials Research InstituteCity of Scientific Research and Technological Applications(SRTA-City)New Borg El-ArabAlexandria21934Egypt

In this study,green zinc oxide(ZnO)/polypyrrole(Ppy)/cellulose acetate(CA)film has been synthesized via solvent *** film was used as supporting material for glucose oxidase(GOx)to sensitize a glucose *** nanoparticles have been prepared via the green route using olive leaves extract as a ***/Ppy nanocomposite has been synthesized by a simple in-situ chemical oxidative polymerization of pyrrole(Py)monomer using ferric chloride(FeCl3)as an oxidizing *** produced materials and the composite films were characterized using X-ray diffraction analysis(XRD),scanning electron microscope(SEm),Fourier transform infrared(FTIR)and thermogravimetric analysis(TGA).Glucose oxidase was successfully immobilized on the surface of the prepared film and then ZnO/Ppy/CA/GOx composite was sputtered with platinum electrode for the current determination at different initial concentrations of *** measurements proved the suitability and the high sensitivity of the constructed biosensor for the detection of glucose levels in different *** performance of the prepared biosensor has been assessed by measuring and comparing glucose concentrations up to 800 *** results affirmed the reliability of the developed biosensor towards real samples which suggests the wide-scale application of the proposed biosensor.

关键词： Biosensors composite films glucose polypyrrole green ZnO cellulose acetate

A review on the multi-scaled structures and mechanical/thermal properties of tool steels fabricated by laser powder bed fusion additive manufacturing

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International Journal of minerals,metallurgy and materials 2024年第5期31卷 1048-1071页

作者： Huajing Zong Nan Kang Zehao Qin mohamed el mansori Arts et metiers Institute of Technology MSMPHESAM UniversitéChâlons-en-Champagne F-51006France Texas A&m Engineering Experiment Station Institute for Manufacturing SystemsCollege Station TX77843USA

The laser powder bed fusion(LPBF) process can integrally form geometrically complex and high-performance metallic parts that have attracted much interest,especially in the molds *** appearance of the LPBF makes it possible to design and produce complex conformal cooling channel systems in ***,LPBF-processed tool steels have attracted more and more *** complex thermal history in the LPBF process makes the microstructural characteristics and properties different from those of conventional manufactured tool *** paper provides an overview of LPBF-processed tool steels by describing the physical phenomena,the microstructural characteristics,and the mechanical/thermal properties,including tensile properties,wear resistance,and thermal *** microstructural characteristics are presented through a multiscale perspective,ranging from densification,meso-structure,microstructure,substructure in grains,to ***,a summary of tool steels and their challenges and outlooks are introduced.

关键词： additive manufacturing laser powder bed fusion tool steel multi-scaled structure mechanical properties thermal properties

Surface morphology and cell viability of samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide/polycaprolactone targeting wound dressing

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Journal of Rare Earths 2024年第3期42卷 555-561,I0005页

作者： muteb H.Alshammari Ahmed Onayzan Alshammari mohamed Tharwat elabbasy Rafat Zreiq Faris mohammed Albati m.A.el-morsy A.A.menazea Department of Health Informatics College of Public Health and Health InformaticsUniversity of Ha'ilHa'ilSaudi Arabia Department of Surgery College of MedicineUniversity of Ha'ilHa'ilSaudi Arabia Department of Public Health College of Public Health and HealthInformaticsHalUniversityHa'il2440Saudi Arabi Food Control Department Faculty of Veterinary MedicineZagazig UniversityZagazig44519Egypt Applied Science Research Center Applied Science Private UniversityAmman541350Jordan College of Shariah and Law Ha'il UniversityHa'il2440Saudi Arabia College of Science and Humanities in Al-Kharj Physics DepartmentPlasma Technology and Material Science UnitPrince Sattam Bin Abdulaziz UniversityAl-kharj11942Saudi Arabia Physics Department Faculty of ScienceUniversity of DamittaNew Damietta34517.Egyp Spectroscopy Department Physics Research InstituteNational Research CentreDokki12622GizaEgypt

Combinations of metal and lanthanide oxides have been done through casted films for potential medical applications. In this regard, samarium(Ⅲ) oxide/chromium(Ⅲ) oxide/graphene oxide(GO)/polycaprolactone(PCL) based films nano-composites(NCs) were fabricated, pointing their utilization as a biological scaffold for wound dressing purposes. Also, samarium(Ⅲ) oxide and chromium(Ⅲ) oxide have been merged as promising optical constituents due to their unique optical behavior. The structural and compositional examination of the studied NCs was executed by X-ray diffraction(XRD), Raman, and field emission scanning electron microscopy(FESEm). The Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL NC exhibits a surface with a lower roughness degree owing to the presence of GO. Cr_(2)O_(3)shows size reduction upon GO insertion to reach 1.2 μm as the average grain size, whilst Sm_(2)O_(3)records an average grain size of less than 1 μm. As well, the polymeric nano-compositions exhibit variation in contact angle values that hit 29.76°± 3.52°for Sm_(2)O_(3)/PCL, and 48.62°± 1.37°for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL as the second lowest contact angle. The optical behavior contributes to absorption edge relocation along the x-axis from 1.7 eV for pure PCL, to 2.65 eV for Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL. Regarding biological responses, the cell exposed to 2.5 μg/m L of Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL shows cell viability of 119.31%, while 5 μg/m L hits 99.6%. Additionally, the resulting cell attachment micrographs show layers of fibroblast tissue, besides the proliferation and growth of cultivated cells. Thus, the Sm_(2)O_(3)/Cr_(2)O_(3)/GO/PCL scaffold provides 3D proliferation of fibroblast cells endorsing the wound healing process.

关键词： Wound healing Wound dressing Polycaprolactone Sm_(2)O_(3) Cr_(2)O_(3) Rare earths