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Large magnetocaloric effect and magnetic properties of EuRhO3

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Journal of Rare Earths 2024年第9期42卷 1724-1729页

作者： M.Lassri M.Sajieddine a.elouafi a.el h.ch.i S.el Ouahbi R.Moubah Laboratory of Energy and Materials Engineering (LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology (FST) institute of Applied Physics (iAP)-School of industrial Management (EMiNES) Mohammed Ⅵ Polytechnic University National School of Applied Sciences (ENSA) University of Sultan Moulay Slimane Laboratory of Mechanics Production and Industrial Engineering (LMPGI)Higher School of Technology of Casablanca (ESTC)University of Hassan Ⅱ Casablanca Laboratory of Radiation on Matter and instrumentation (LRMi) Faculty of Science and Technology (FST) SettatHassan Ⅰ University Laboatory of Physics of Advanced Materials and Thermic (LPMAT) Faculty of Science Ain Chock (FSAC)University of Hassan Ⅱ Casablanca

We report on the structural,magnetic,and magnetocaloric properties of *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy（XPS）.it is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***3powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature（TN=2.9 K）.Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/（T-θW）) for T>TN,yields θW=-3.1 K and effective magne tic moment ■,wh.ch.is close to the theoretical value ■.The magnetic entropy change(-ΔSM),was determined by em ploying the thermodynam ic Maxwell's *** μ0h=5 T and near TN,■ and relative cooling power（RCP） exhibit large values of 33.7 J/（kg·K） and 238 J/kg,*** large magnitude of-ΔSMand RCP show that the EuRhO3compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths X-ray photoelectron spectroscopy

Large magnetocaloric effect and magnetic properties of EuRhO_(3)

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Journal of Rare Earths 2024年第9期42卷 1724-1729,I0004页

作者： M.Lassri M.Sajieddine a.elouafi a.el h.ch.i S.el Ouahbi R.Moubah Laboratory of Energy and Materials Engineering(LGEM) University of Sultan Moulay SlimaneFaculty of Science and Technology(FST)BP 52323000Béni-MellalMorocco institute of Applied Physics(iAP)-School of industrial Management(EMiNES) Mohammed Ⅵ Polytechnic UniversityHay Moulay RachidLot 6603150Ben GuerirMorocco National School of Applied Sciences(ENSA) University of Sultan Moulay SlimaneBP 7725000KhouribgaMorocco Laboratory of Mechanics Production and Industrial Engineering(LMPGI)Higher School of Technology of Casablanca(ESTC)University of Hassan Ⅱ CasablancaCasablancaMorocco Laboratory of Radiation on Matter and instrumentation(LRMi) Faculty of Science and Technology(FST)SettatHassan Ⅰ UniversitySettatMorocco Laboatory of Physics of Advanced Materials and Thermic(LPMAT) Faculty of Science Ain Chock(FSAC)University of Hassan Ⅱ CasablancaCasablancaMorocco

We report on the structural,magnetic,and magnetocaloric properties of EuRhO_(3) *** oxidation states of Eu and Rh ions were studied using X-ray photoelectron spectroscopy(XPS).it is found that the Eu ions are mainly in the divalent oxidation state while the Rh ions have+4 ***_(3) powders are found to be antiferromagnetic with a second order magnetic transition at Neel temperature(T_(N)=2.9 K).Analysis of the magnetic susceptibility versus temperature data in terms of the Curie=Weiss law:(χ=C/(T-θ_(W))) for T>T_(N),yields θ_(W)=-3.1 K and effective magne tic moment μ_(ff)^(exp),wh.ch.is close to the theoretical value μ_(eff)^(theo).The magnetic entropy change(-Δ_(SM)),was determined by em ploying the thermodynam ic Maxwell's *** μ_0h=5 T and near T_(N),ΔS_(M)^(Max) and relative cooling power(RCP) exhibit large values of 33.7 J/(kg·K) and 238 J/kg,*** large magnitude of-Δ_(SM) and RCP show that the EuRhO_(3) compound could be a potential candidate to be used in cryogenic magnetic refrigeration.

关键词： X-ray photoelectron spectroscopy Cryogenic magnetic refrigeration Magnetic properties Magnetocaloric effect Rare earths

An introductory review of swarm technology for spacecraft on-orbit servicing

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international Journal of Mechanical System Dynamics 2024年第1期4卷 3-21页

作者： el Ghali Asri Zheng h.Zhu Department of Mechanical Engineering York UniversityTorontoOntarioCanada

This review paper presents a comprehensive evaluation and forward-looking perspective on the underexplored topic of servicing target objects using spacecraft *** targets can be known or unknown,cooperative or uncooperative,and pose significant challenges in modern space operations due to their inherent complexity and *** servicing space objects is vital for active debris removal and broader on-orbit servicing tasks such as sa.ellite maintenance,repair,refueling,orbital assembly,and *** effort has been invested in the literature to explore the servicing of targets using a single *** its advantages and benefits,this paper expands the discussion to encompass a swarm approach to the *** review covers various single-spacecraft approaches and presents a critical examination of the existing,although limited,body of work dedicated to servicing orbital objects using multiple *** focus is also broadened to include some influential studies concerning the characterization,capture,and manipulation of physical objects by general multiagent systems,a subject with significant parallels to the core interest of this ***,this article also delves into the realm of simultaneous localization and mapping,highlighting its application within close-proximity operations in space,especially when dealing with unknown uncooperative *** attention is paid to the benefits that this field can receive from distributed multiagent ***,an exploration of the promising field of swarm robotics is presented,with an emphasis on its potential to revolutionize the servicing of orbital target ***,a survey of general research directly engaging swarms in the orbital context is *** review aims to bridge the knowledge gap and stimulate further research in the underexplored domain of servicing space targets with spacecraft swarms.

关键词： space robotics on-orbit servicing close-proximity operations guidance and navigation swarm robotics multiagent systems object capture and manipulation simultaneous localization and mapping

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

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hematobiochemical and histopathological alterations in Nile Tilapia(Oreochromis niloticus)exposed to ethidium bromide:The protective role of Spirulina platensis

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Aquaculture and Fisheries 2024年第1期9卷 93-103页

作者： Sabreen Abdullah Mervat Naguib Alaa.el-Din Salah el-Din Alaa.el-Din h.Sayed Zoology Department Faculty of ScienceAswan UniversityAswan81528Egypt Zoology Department Faculty of ScienceAssuit UniversityAssiut71516Egypt

Ethidium bromide(EtBr)is one of the contaminants recorded in aquatic environments whose effects have been investigated;however,there is still limited knowledge about its *** study examined the potential protective effects of Spirulina platensis(SP)against the effects of EtBr toxicity in the Nile tilapia(Oreochromis niloticus)*** were divided to five groups,viz.,a control and four treatment groups of low-dose EtBr(10μg/L),low-dose EtBr with SP(10μg/L EtBr+200 mg/L SP),high-dose EtBr(100μg/L),and high-dose EtBr with SP(100μg/L EtBr+200 mg/L SP);the exposure period was 2 *** and high doses of EtBr induced alterations in some hematological,biochemical,and histopathological *** hepatocytes,degenerated area,vacuolated hepatocytes,pyknotic nuclei,constricted and dilated blood sinusoids,and infiltration of inflammatory cells were *** peroxidation concentration was not significantly different in groups exposed to low doses of EtBr and EtBr with SP,but it was increased in groups exposed to high doses of EtBr and EtBr with SP,compared with the control *** feeding with SP,most histological and histochemical parameters restored to normal ***,SP may possess the ability to preserve the structural integrity of the hepatic and renal membranes.

关键词： Ethidium bromide Spirulina platensis Oreochromis niloticus Liver Lipid peroxidation

Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern Saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour h.Al-hashim Abdelbaset S.el-Sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red Sea, northwestern Saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. Sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in Sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry Saudi Arabia

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Eco-toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface sediments of Burullus Lake in Egypt

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china Geology 2024年第3期7卷 460-468页

作者： hanan E Osman Mohamed h E el-Morsy hazem T Abd el-hamid Department of Biology Faculty of Applied ScienceUmm Al-Qura UniversityMecca 24382Saudi Arabia Deanship of Scientific Research Umm Al-Qura UniversityMakkah 24372Saudi Arabia National institute of Oceanography and Fisheries(NiOF) Cairo 11865Egypt Botany and Microbiology Department Faculty of ScienceAl-Azhar UniversityCairo 11651Egypt

Polycyclic aromatic hydrocarbons(PAhs)are ubiquitous environmental contaminants of growing concern due to their potential ecological and human health *** study presents a comprehensive assessment of PAhs contamination in the surface sediments of Burullus Lake,a vital and second largest delta lake in *** aim was to evaluate the eco-toxicity and potential health risks associated with the presence of these *** seven sediment samples were collected from various drains in the southern part of Burullus *** extraction method was employed to extract PAhs(16PAhs)from the sediment ***,target compounds were located using *** results showed that samples contained PAhs levels ranging from 0.038×10^(-6)to 0.459×10^(-6),wh.ch.is considered heavily polluted by the European standard for PAhs ***,there was no apparent source of PAhs in the elKhashah drain or the Brinbal Canal,as hPLC found none of the *** most prevalent compound in sediment samples along the study area was *** diagnostic indices in the present study indicated that the hydrocarbons in the region originated from pyrolytic and man-made sources along the drains of Burullus *** principal component analysis(PCA)and diagnostic ratios revealed that coal combustion and pyrolytic sources were responsible for the PAhs contamination in the surface *** non-carcinogenic risk(hi),wh.ch.is the product of the hQs for the adult and child populations,respectively,was *** values under 1,therefore,demonstrated that they had no carcinogenic effects on human *** and MEQs in the sediments of Burullus Lake do not have a cancer-causing impact on *** the safety of nearby wildlife,aquatic life,and people,all activities that raise petroleum hydrocarbon levels in Burullus Lake must be adequa.ely regulated and *** to the ecological risk assessment,there is little chance that PAhs will be found

关键词： Polycyclic aromatic hydrocarbons Diagnostic indices Toxicity Delta lake sediment Burullus Lake human health risk Aquatic ecosystem hPLC Coal combustion

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Rao Algorithms-Based Structure Optimization for heterogeneous Wireless Sensor Networks

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Computers, Materials & Continua 2024年第1期78卷 873-897页

作者： Shereen K.Refaay Samia A.Ali Moumen T.el-Melegy Louai A.Maghrabi hamdy h.el-Sayed Faculty of Computers and Artificial intelligence Sohag UniversitySohag82524Egypt Faculty of Engineering Assiut UniversityAssiut711745Egypt College of Engineering University of Business and TechnologyJeddah23411Saudi Arabia

The structural optimization of wireless sensor networks is a critical issue because it impacts energy consumption and hence the network’s *** studies have been conducted for homogeneous networks,but few have been performed for heterogeneouswireless sensor *** paper utilizes Rao algorithms to optimize the structure of heterogeneous wireless sensor networks according to node locations and their initial *** proposed algorithms lack algorithm-specific parameters and metaphorical *** proposed algorithms examine the search space based on the relations of the population with the best,worst,and randomly assigned *** proposed algorithms can be evaluated using any routing protocol,however,we have chosen the well-known routing protocols in the literature:Low Energy Adaptive Clustering hierarchy(LEAch),Power-Efficient Gathering in Sensor information Systems(PEAGSiS),Partitioned-based Energy-efficient LEAch(PE-LEAch),and the Power-Efficient Gathering in Sensor information Systems Neural Network(PEAGSiS-NN)recent routing *** compare our optimized method with the Jaya,the Particle Swarm Optimization-based Energy Efficient Clustering(PSO-EEC)protocol,and the hybrid harmony Search Algorithm and PSO(hSA-PSO)*** efficiencies of our proposed algorithms are evaluated by conducting experiments in terms of the network lifetime(first dead node,half dead nodes,and last dead node),energy consumption,packets to cluster head,and packets to the base *** experimental results were compared with those obtained using the Jaya optimization *** proposed algorithms exhibited the best *** proposed approach successfully prolongs the network lifetime by 71% for the PEAGSiS protocol,51% for the LEAch protocol,10% for the PE-LEAch protocol,and 73% for the PEGSiS-NN protocol;Moreover,it enhances other criteria such as energy conservation,fitness convergence,packets to cluster head,and packets to the base sta

关键词： Wireless sensor networks Rao algorithms optimization LEAch PEAGSiS

Microbial,immune and antioxidant responses of Nile tilapia with dietary nano-curcumin supplements under chronic low temperatures

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Aquaculture and Fisheries 2024年第1期9卷 57-65页

作者： Mohammed F.el Basuini Mohamed A.A.Zaki Abdelaziz M.el-hais Mohamed G.elhanafy Emad h.el-Bilawy Amr i.Zaineldin Mohamed F.A.Abdel-Aziz ibrahim A.Abouelsaad ibrahim Tel-Ra.el Kumbukani Mzengereza Ronick S.Shadrack islam i.Teiba Faculty of Agriculture Tanta UniversityTanta31527Egypt King Salman international University South Sinai46618Egypt Faculty of Agriculture Alexandria UniversityAlexandria21526Egypt Animal health Research institute(AhRi-DOKi) Agriculture Research CenterGiza12619Egypt Fish Rearing Lab. Aquaculture DivisionNational Institute of Oceanography and FisheriesAlexandria21556Egypt horticulture Department Faculty of AgricultureDamanhour UniversityDamanhur22511Egypt Department of Poultry Production Faculty of AgricultureDamietta UniversityDamietta34517Egypt Laboratory of Aquatic Animal Nutrition Faculty of FisheriesKagoshima UniversityKagoshima890-0065Japan Department of Aquatic and Fisheries Science Mzuzu UniversityMzuzuPrivate Bag 201Malawi Faculty of Aquaculture and Marine Fisheries Arish UniversityArish45516Egypt

A 56-day feeding period was performed to investigate the possible impacts of dietary nano curcumin(0,50,100,150,and 200 ppm)on the growth,nutrient utilization,non-specific immune parameters,antioxidants in Nile tilapia under chronic low temperature(21.02±0.11◦C).Fishes(n=225;initial weight=4.39±0.08 g/fish)were randomly stocked at 15 fish/tank for five experimental groups in *** low-temperature circumstances,dietary curcumin in nano form showed no notable alteration in growth variable,nutrient efficiency,digestive enzymes efficiency,biometric indices,survival rates,and hematological ***,the serum of fishes with nano curcumin diets under low-temperature stress displayed higher total protein as well as lower glucose,cortisol,and total cholesterol compared with the control ***,fish fed nano curcumin diets displayed higher lysozyme and bactericidal activities compared to the control group and the best performance was found at dietary nano curcumin level of≥100 ***,groups fed the basal diet demonstrated the poorest antioxidant capacity,and the best superoxide dismutase(SOD)and glutathione peroxidase(GPx)existed in fish with nano curcumin diets while the best catalase(CAT)efficiency occurred at higher nano curcumin levels≥100 *** addition,higher counts of intestinal microbiota in terms of total bacterial count(TBC),total yeast and molds count(TYMC),and coliform were noticed in fish consumed the basal diet compared to groups fed on nano curcumin *** conclusion,incorporating nano curcumin at a level of≥100 mg/kg diet(particularly at 150 mg/kg)improved a non-specific immune response,antioxidant,and healthier gastrointestinal microbiota in Nile tilapia under chronic low-temperature stress.

关键词： Nano curcumin Gastrointestinal microbiota Antioxidants Non-specific immune responses Temperature stress