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multiple scales method for analyzing a forced damped rotational pendulum oscillatorwithgallows

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Communications in Theoretical Physics 2024年第5期76卷 58-67页

作者： haifa A Alyousef Alvaro h salas B m Alotaibi s A El-Tantawy Department of Physics College of SciencePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh 11671Saudi Arabia Department of mathematics and statistics Universidad Nacional de ColombiaFIZMAKO Research GroupColombia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversityAl-Baha 1988Saudi Arabia

This study reports the analytical solution for a generalized rotational pendulum system with gallows and periodic excited *** multiple scales method(msm)is applied to solve the proposed *** types of rotational pendulum oscillators are studied and talked about in *** include the forced damped rotating pendulum oscillator with gallows,the damped standard simple pendulum oscillator,and the damped rotating pendulum oscillator without *** msm first-order approximations for all the cases mentioned are derived in *** obtained results are illustrated with concrete numerical *** first-order msm approximations are compared to the fourth-order Runge-Kutta(RK4)numerical ***,the maximum error is estimated for the first-order approximations obtained through the msm,compared to the numerical approximations obtained by the RK4 ***,we conducted a comparative analysis of the outcomes obtained by the used method(msm)and he-msm to ascertain their respective levels of *** proposed method can be applied to analyze many strong nonlinear oscillatory equations.

关键词： rotational pendulum system multiple scales method approximate solution damped oscillations forced pendulum with gallows he-multiple scales method

Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： h.m.FEIZABAD m.h.YAs Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

mgO-attached graphene nanosheet(mgO@GNs)reinforced magnesium matrix nanocomposite with superior mechanical,corrosion and biological performance

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International Journal of minerals,metallurgy and materials 2024年第9期31卷 2062-2076页

作者： s.Abazari A.shamsipur h.R.Bakhsheshi-Rad m.s.soheilirad F.Khorashadizade s.s.mirhosseini Department of materials and metallurgical Engineering Amirkabir University of TechnologyTehran ***Iran Iranian National standards Organization of hormozgan HormozganIran Advanced materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran Department of materials and metallurgical Engineering Iran University of Science and TechnologyTehranIran

magnesium(mg)alloys are gaining great consideration as body implant materials due to their high biodegradability and ***,they suffer from low corrosion resistance and antibacterial *** this research,semi-powder metallurgy followed by hot extrusion was utilized to produce the magnesium oxide@graphene nanosheets/magnesium(mgO@GNs/mg)composite to improve mechanical,corrosion and cytocompatibility *** have revealed that the incorporation of mgO@GNs nanohybrids into mg-based composite enhanced microhardness and compressive *** vitro,osteoblast cell culture tests show that using mgO@GNs nanohybrid fillers enhances osteoblast adhesion and apatite *** presence of mgO@GNs nanoparticles in the composites decreased the opening defects,micro-cracks and micro-pores of the composites thus preventing the penetration of the corrosive solution into the *** demonstrated that the mgO@GNs/mg composite possesses excellent antibacterial properties because of the combination of the release of mgO and physical damage to bacterium membranes caused by the sharp edges of graphene nanosheets that can effectively damage the cell wall thereby facilitating penetration into the bacterial lipid ***,the mgO@GNs/mg composite with high mechanical strength,antibacterial activity and corrosion resistance is considered to be a promising material for load-bearing implant applications.

关键词： metal matrix composites mgO@GNs nanohybrid strengthening mechanisms antibacterial activity biocompatibility

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)snO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.hamad Nidal Dwaikat m.h.A.mhareb m.I.sayyed R.m.hamad Y.s.m.Alajerami m.A.Almessiere Gameel saleh Ahmad hussein Alomari K.A.Ziq Department of Basic sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)snO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOm computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)snO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding mass stopping power Rare earths

search for production of dark fermion candidates in association with heavy neutral gauge boson decaying to dimuon in proton-proton collisions at√s=8 TeV using Cms open data

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Chinese Physics C 2024年第4期48卷 6-13页

作者： Y.mahmoud h.Abdallah m.T.hussein s.Elgammal Centre for theoretical physics The British University in EgyptEgypt Physics Department Faculty of ScienceCairo UniversityEgypt

In this study,we conducted a search for dark matter using a part of the data recorded by the Cms experiment during run-I of the LhC in 2012 with a center of mass energy of 8 TeV and an integrated luminosity of 11.6 fb−*** data were gathered from the Cms open *** matter,in the framework of the simplified model(mono-Z′),can be produced from proton-proton collisions in association with a new hypothetical gauge boson,Z′.Thus,the search was conducted in the dimuon plus large missing transverse momentum *** benchmark scenario of mono-Z′,which is known as light vector,was used for interpreting the Cms open *** evidence of dark matter was observed,and exclusion limits were set on the masses of dark matter and Z′at 95%confidence level.

关键词： dark matter large hadron collider Cms open data search for new physics dark fermion

Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear science and Techniques 2024年第5期35卷 122-130页

作者： s.madhu h.C.manjunatha N.sowmya B.m.Rajesh L.seenappa R.s.susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 meV for ^(53)Cr+^(243)Am,23.2 fb at 236 meV for ^(54)Cr+^(247)Cm,95.6 fb at 240 meV for ^(53)Cr+248Bk,and 1.33 fb at 242 meV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability survival probability Evaporation residue cross sections

Physical Layer security of 6G Vehicular Networks with UAV systems: First Order secrecy metrics, Optimization, and Bounds

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Computers, materials and Continua 2024年第3期80卷 3685-3711页

作者： Kavaiya s. mewada h. Patel s. Chauhan D. Almalki F.A. mujlid h.m. smt. Chandaben mohanbhai Patel Institute of Computer Applications Charotar University of Science and Technology Anand Changa 388421 India Electrical Engineering Department Prince Mohammad Bin Fahad University P.O. Box 1664 Al Khobar 31952 Saudi Arabia Department of Electronics and Communication Engineering Chandubhai S. Patel Institute of Technology Charotar University of Science and Technology Anand Changa 388421 India Department of Computer Engineering College of Computers and Information Technology Taif University P.O. Box 11099 Taif 21944 Saudi Arabia

The mobility and connective capabilities of unmanned aerial vehicles (UAVs) are becoming more and more important in defense, commercial, and research domains. however, their open communication makes UAVs sus***,theinefficiencyoftraditional cryptography-based techniques has led to the addition of Physical Layer security (PLs). This study focuses on the advanced PLs method for passive eavesdropping in UAV-aided vehicular environments, proposing a solution to complement the conventional cryptography approach. Initially, we present a performance analysis of first-order secrecy metrics in 6G-enabled UAV systems, namely hybrid outage probability (hOP) and secrecy outage probability (sOP) over 2 × 2 Nakagami-m channels. Later, we propose a novel technique for mitigating passive eavesdropping, which considers first-order secrecy metrics as an optimization problem and determines their lower and upper bounds. Finally, we conduct an analysis of bounded hOP and sOP using the interactive Nakagami-m channel, considering the multiple-input-multiple-output configuration of the UAV system. The findingsindicatethat2×2Nakagami-misasuitablefadingmodelunderconstantvelocityfortrustworthyreceivers and eavesdroppers. The results indicate that UAV mobility has some influence on an eavesdropper’s intrusion during line-of-sight-enabled communication and can play an important role in improving security against passive eavesdroppers. Copyright © 2024 The Authors. Published by Tech science Press.

关键词： 3D positioning 6G communications Physical layer security UAV systems

sodium nitroprusside as a signal molecule for up-regulating membrane characteristics, antioxidant defense system to improve flax productivity under water stress

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Oil Crop science 2024年第3期9卷 160-169页

作者： Al-Ashkar N.m. Bakry B.A. El-Bassiouny h.m.s. Abdallah m.m.s. sadak m.s. Botany Department Agricultural and Biological Research Institute National Research Centre 33 El Bohouth Street P.O. 12622 Dokki Giza Egypt Field Crops Research Department Agricultural and Biological Research Institute National Research Centre 33 El Bohouth Street P.O. 12622 Dokki Giza Egypt

Water stress is a critical environmental adversity that significantly impacts the growth, development, and yield of flax plants. In this study, flax seeds were cultivated under different water irrigation requirements (WIR) (100%, 75%, and 50%) to investigate the effects of exogenously supplied nitric oxide (NO) donor sodium nitroprusside (sNP) as foliar treatments at concentrations of 0.0 mmol/L, 0.5 mmol/L, 1.0 mmol/L, and 2.0 mmol/L. Drought stress led to a significant decrease in plant growth, photosynthetic pigments, yield components such as oil and total carbohydrate percentage. It also resulted in an increase in leaf h2O2 production, lipid peroxidation levels and activities of enzymatic antioxidants including polyphenol oxidase, superoxide dismutase, and nitrate reductase enzymes. however, foliar application of sNP improved photosynthetic pigments and antioxidant defense system which mitigated the negative impact of water stress on growth and yield productivity by reducing oxidative damage caused by reactive oxygen species accumulation. The use of sNP also decreased h2O2 accumulation levels, lipid peroxidation levels, and improved membrane stability. sNP treatment at concentration of 2 mmol/L showed superior results compared to other concentrations with extremely significant increases observed in yield characteristics such as oil content, total carbohydrate percentages, and unsaturated fatty acids to saturated fatty acids ratio. © 2024 the Oil Crop Research Institute, Chinese Academy of Agriculture sciences

关键词： Antioxidant enzymes Fatty acid Flax sodium nitroprusside Yield

magnesium oxide(mgO)nanoadsorbents in wastewater treatment:A comprehensive review

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Journal of magnesium and Alloys 2024年第5期12卷 1709-1773页

作者： h.C.s.Perera V.Gurunanthanan Anoop singh m.m.m.G.P.G.mantilaka G.Das sandeep Arya Department of Physics Khalifa UniversityAbu Dhabi12788United Arab Emirates Postgraduate Institute of science University of PeradeniyaPeradeniyaSri Lanka Department of humanities and sciences Guru Nanak Institutions Technical CampusIbrahimpatnamHyderabad501506India Centre for Global health Research Saveetha Medical College and HospitalsSaveetha Institute of Medical and Technical SciencesChennai602105Tamil NaduIndia Department of Physics University of JammuJammu and Kashmir180006India

Wastewater contamination by heavy metals and synthetic dyes presents a significant environmental challenge,necessitating effective and sustainable separation *** review article provides a detailed examination of magnesium oxide(mgO)nanoparticles as an innovative nanoadsorbent for wastewater treatment,with a specific focus on heavy metal and dye *** review comprehensively explores various aspects of mgO nanoparticles,including their structural characteristics and synthesis *** article delves into the morphology and crystallographic arrangement of mgO nanoparticles,offering insights into their structural *** the complexity of adsorption processes,the review identifies and analyzes parameters influencing the adsorption efficiency of mgO nanoparticles,such as temperature,ph,contact time,initial concentration,and co-existing *** interplay between these parameters and the adsorption capability of mgO nanoparticles emphasizes the importance of optimizing operational ***,the review assesses various synthesis methods for mgO nanoparticles,including sol-gel,hydrothermal,precipitation,green synthesis,solvothermal,and template-assisted *** discusses the advantages,limitations,and resulting nanoparticle characteristics of each method,enabling readers to grasp the implications of synthesis processes on adsorption *** comprehensive review consolidates current insights into the effectiveness of mgO nanoparticles as a potent nanoadsorbent for removing heavy metals and dyes from wastewater covering a wide spectrum of aspects related to mgO ***,there is a need to investigate the use of mgO in the treatment of actual wastewater or river water,in order to leverage its cost-effectiveness and high efficiency for practical water treatment applications in real-time.

关键词： mgO nanoparticles Nanoadsorbent Wastewater treatment heavy metals Dye separation Adsorption synthesis methods