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Collisionless shock acceleration of protons in a plasma slab produced in a gas jet by the collision of two laser-driven hydrodynamic shockwaves

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matter and Radiation at Extremes 2024年第2期9卷 12-25页

作者： J.-R.marquès L.Lancia P.Loiseau P.forestier-Colleoni m.Tarisien E.Atukpor V.Bagnoud C.Brabetz f.Consoli J.Domange f.Hannachi P.Nicolaï m.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helmholtzzentrum für Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany University of Darmstadt Schloßgartenstr.764289 DarmstadtGermany ENEA fusion and Technologies for Nuclear Safety Department C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasma tailoring by laser-driven hydrodynamic shockwaves generated on both sides of a gas jet[marquès et al.,*** 28,023103(2021)].In a continuation of this numerical work,we study experimentally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum,produced by Coulomb *** the front side of the gas jet is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasma are *** forward acceleration produces higher-energy protons,with a peaked spectrum,and is in good agreement with the mechanism of collisionless shock acceleration(CSA).The spatiotemporal evolution of the plasma profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam are simulated by post-processing 3D hydrodynamic simulations of the plasma *** with the experimental results allows estimation of the thickness and near-critical density of the plasma slab produced by tailoring both sides of the gas *** parameters are in good agreement with those required for CSA.

关键词： acceleration hydrodynamic collision

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添加大豆黄酮对肉种鸡产蛋高峰后期产蛋率、抗氧化活性及肝VTG-ⅡmRNA表达变化的影响

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饲料博览 2013年第1期23卷 4-4页

作者： Yasin m Asghar A anjum f m Butt m S Khan m I Arshad m S Shahid m El-Ghorab A H Shibamoto T

大豆黄酮即大豆植物雌激素,是一种强抗氧化剂,具有多种生物活性。研究通过在肉种鸡产蛋后期饲喂大豆苷元来证实大豆黄酮提高产蛋率的作用,并通过相关基因表达的变化和肝脏的抗氧化状态来阐明这个过程的机制。选择460日龄的肉种鸡300只,... 详细信息

大豆黄酮即大豆植物雌激素,是一种强抗氧化剂,具有多种生物活性。研究通过在肉种鸡产蛋后期饲喂大豆苷元来证实大豆黄酮提高产蛋率的作用,并通过相关基因表达的变化和肝脏的抗氧化状态来阐明这个过程的机制。选择460日龄的肉种鸡300只,随机分成3组(每组100只,设10个重复,每个重复10只),分别饲喂基础日粮(对照组,CON)或在基础日粮中添加大豆黄酮5mg·kg-1(低剂量,L)或10mg·kg-1(高剂量,H)。预饲期1周,试验期15d。试验结果表明,添加大豆黄酮的高和低剂量均显著提高产蛋率(P0.05)。血清雌激素表现出剂量依赖性减少,且添加大豆黄酮高剂量组与其他组相比差异显著(P0.05)。大豆黄酮显著降低血清丙二醛含量(P0.05)。实时PCR分析结果表明,大豆黄酮组的母鸡随着产蛋率的增加,肝脏卵黄蛋白原-Ⅱ表达显著下降(PmRNA的表达显著上升(P0.05)。结果表明,添加大豆黄酮可通过提高抗氧化能力和不断改变肉鸡肝相关基因的转录来提高产蛋率。

关键词：产蛋率抗氧化基因表达大豆苷元肉种鸡

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The global stability and optimal control of the COVID-19 epidemic model

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International Journal of Biomathematics 2024年第1期17卷 1-28页

作者： fengsheng Chien Hassan Saberi Nik mohammad Shiraziant J.f.Gomez-Aguilar School of finance and Accounting fuzhou University of International Studies and Trade fuzhou 352020 P.R.China faculty of Business City university of Macao Macao 999078P.R.China Department of mathematics and Statistics University of Neyshabur NeyshaburIran CONACyT-Tecnologico Nacional de mécico/CENIDET Interior Internado Palmira S/N Col.Palmira C.P.62490CuernavacaMorelosMérico

This paper considers stability analysis of a Susceptible-Exposed-Infected-Recovered-Virus(SEIRV)model with nonlinear incidence rates and indicates the severity and weakness of control factors for disease *** Lyapunov function using Volterra-Lyapunov matrices makes it possible to study the global stability of the endemic equilibrium *** optimal control strategy is proposed to prevent the spread of coronavirus,in addition to governmental *** objective is to minimize together with the quantity of infected and exposed individuals while minimizing the total costs of treatment.A numerical study of the model is also carried out to investigate the analytical results.

关键词： Global stability SEIRV epidemic model dynamical systems Volterra-Lyapunov stability optimal control

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Enhancing high-temperature oxidation resistance(at 1000 °C) of nickel superalloy obtained by laser powder bed fusion via reactive electric spark treatment

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Transactions of Nonferrous metals Society of China 2024年

作者： S.K.mUKANOV m.I.PETRZHIK A.E.KUDRYASHOV E.A.NAUmOVA f.A.BASKOV P.A.LOGINOV E.A.LEVASHOV National University of Science and Technology mISIS

The high-temperature oxidation resistance of the nickel superalloy grown by the Laser Powder Bed fusion (LPBf) has been significantly increased as a result of in-situ formation of a thermal barrier layer (α-Al2O3+ CamoO4) during oxidative annealing of surface layers modified by electric spark treatment (EST). The reactive EST of the LPBf-built items based on nickel EP741NP alloy was carried out with low-melting Al-12%Si， Al-6%Ca-0.6%Si and Al-7%Ca-1%mn electrodes. It was found that at EST done by Al-7%Ca-1%mn electrode an intermetallic (β-NiAl + γ’-Ni3Al) 15 microns thick layer reinforced by spherical oxide (Came)O nanoparticles was formed. formation of that structure increases the wear resistance of LPBf nickel superalloy by 4.5 times. further oxidative annealing at 1000 °C lead to a formation of continuous two-layered coating with an inner layer of α-Al2O3and an outer layer of CamoO4， which together act as an effective barrier preventing the diffusion of oxygen into the volume of the superalloy.

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Percolation analysis of large-scale wireless balloon networks

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Digital Communications and Networks 2019年第2期5卷 84-93页

作者： m.D. Nashid anjum Honggang Wang Hua fang University of massachusetts Dartmouth 285 Old Westport RdDartmouthMA 02747USA

Recent advancements in wireless technology have tested Wireless Balloon Networks (WBNs) as an ideal solution for the provision of internet facilities in deprived and challenging areas. A few high profile companies, such as Google, Space Data Inc., etc., have already made news by initiating projects based on high-altitude WBNs in order to provide internet facilities in remote areas. Unfortunately, the technical details have mainly been kept confidential so far. In this paper, we attempt to analyze the percolation properties of large-scale WBNs, considering both homogenous and heterogenous wireless nodes. In order to do so, we modeled a WBN as a large-scale random network where the path-loss models of homogenous and heterogenous WBNs were reduced to GDm (Gilbert's Disk model) and RGDm (Random Gilbert's Disk model), respectively. The bounds of the critical density regime were derived for both percolation models. Additionally, this paper implemented an experimental test bed for the WBN percolation model. Consequently, the findings of this research may prove crucial in estimating critical network properties.

关键词： Percolation Connectivity WBN PPP GDm

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A novel diagnostic gene region for distinguishing between two pest fruit flies:Bactrocera tryoni(froggatt)and Bactrocera neohumeralis(Hardy)(Diptera:Tephritidae)

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Insect Science 2024年第4期31卷 1285-1295页

作者： melissa L.Starkie Elizabeth V.fowler Alexander m.Piper Xiaocheng Zhu Pauline Wyatt David Gopurenko matt N.Krosch francesca Strutt Karen f.Armstrong Hamish Patrick mark K.Schutze mark J.Blacket Department of Agriculture and fisheries BiosecurityBrisbaneQueenslandAustralia Agriculture Victoria AgriBioBundooraVictoriaAustralia Department of Primary Industries Wagga Wagga Agricultural InstituteWagga WaggaNew South WalesAustralia forensic Services Group Queensland Police ServiceBrisbaneQueenslandAustralia Department of Pest-management and Conservation Lincoln UniversityLincolnNew Zealand Better Border Biosecurity(B3 B3nz.org.nz)LincolnNew Zealand

Bactrocera tryoni and Bactrocera neohumeralis are morphologically similar sibling pest fruit fly species that possess different biological attributes,geographic distributions,and host *** need to differentiate between the two species is critical for accurate pest status assessment,management,biosecurity,and maintenance of reference *** morphologically similar,adults may be separated based on subtle characters;however,some characters exhibit intraspecific variability,creating overlap between the two ***,there is currently no single molecular marker or rapid diagnostic assay that can reliably distinguish between *** and ***;therefore,ambiguous samples remain *** we report the first molecular marker that can consistently distinguish between *** and *** diagnostic region consists of two adjacent single nucleotide polymorphisms(SNPs)within the pangolin(pan)gene *** confirmed the genotypes of each species are consistent across their distributional range,then developed a tetra-primer amplification refractory mutation system(ARmS)PCR assay for rapid diagnosis of the *** assay utilizes four primers in multiplex,with two outer universal primers,and two internal primers:one designed to target two adjacent SNPs(AA)present in *** and the other targeting adjacent SNPs present in ***(GG).The assay accurately discriminates between the two species,but their SNP genotypes are shared with other nontarget tephritid fruit fly ***,this assay is most suited to adult diagnostics where species confirmation is necessary in determining ambiguous surveillance trap catches;maintaining pure colony lines;and in Sterile Insect Technique management responses.

关键词： ARmS-PCR colony molecular diagnostics pangolin tetra-primer

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microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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Journal of materials Science & Technology 2024年第4期171卷 80-93页

作者： Y.H.Zhang H.Li Z.W.Yang X.Liu Q.f.Gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SmA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SmA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SmA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(m_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SImVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SImVs,the further growth of existing SImVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy Wide transformation hysteresis Thermomechanical loading microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning

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Anisotropic extensions of isotropic finch–Skea metric in the charged modified gravity

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Communications in Theoretical Physics 2024年第9期76卷 118-140页

作者： Tayyab Naseer m Sharif Department of mathematics and Statistics The University of Lahore1-Km Defence RoadLahore 54000Pakistan

In this study,we explore the finch–Skea perfect fluid solution and extend its domain to three distinct anisotropic interior models within the framework of the f(R,T)theory,incorporating the influence of an electromagnetic *** assume a static spherical spacetime initially coupled with an isotropic matter *** then introduce a Lagrangian corresponding to an additional gravitating source,taking into account its role in inducing pressure anisotropy within the original fluid *** deriving the field equations for the combined matter setup,we applied a radial component transformation,which yielded two distinct systems of *** addition,we consider a charged exterior spacetime to determine the three constants associated with the finch–Skea solution at the *** findings suggest that under certain parametric choices,all three resulting models exhibited physical relevance within this modified theory.

关键词： anisotropy modified gravity gravitational decoupling

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Wear dependent virtual flow rate sensor for progressing cavity pumps with deformable stator

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Petroleum Science 2024年第2期21卷 1346-1353页

作者： Jens müller Sebastian Leonow Johannes Schulz Christian Hansen martin monnigmann Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX GmbH Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pumps. We study the wear-induced material loss of the pump components and the impact of this material loss on the volumetric efficiency. The results are combined with an established backflow model to implement a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pump from new to worn condition to validate our approach. The obtained measurement data show that the presented virtual sensor is capable of calculating the flow rate of a pump being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pump Virtual sensor Wear

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Localized-states quantum confinement induced by roughness in CdmnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde N.Rodrigues Wesley f.Inoch marcos L.f.Gomes Odilon D.D.Couto Jr. Bráulio S.Archanjo Sukarno O.ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdmnTe/CdTe/CdmnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdmnTe/CdTe/CdmnTe heterostructure CdTe/CdmnTe quantum emitters quantum dot-like emission silicon(111)substrate

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