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Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.R.Dil Kumar s.j.Mija Department of electrical engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/simulink platform. since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PsO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PsO) PsO PID controller

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.j.Li j.h.Chu M.M.Li D.N.Zou L.B.Tong school of Metallurgical engineering Xi’an University of Architecture and TechnologyXi’an 710055China state Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WeP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WeP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene epoxy coating Corrosion/wear resistance Blocking layer

supramolecular Polymerization of hydrogen-Bonded Trimers in Bulk and Aqueous Medium

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CCs Chemistry 2024年第6期6卷 1458-1465页

作者： Freek V.de Graaf stef A.h.jansen sandra M.C.schoenmakers Bas van Genabeek Marle e.j.Vleugels Bart W.L.van den Bersselaar e.W.Meijer Ghislaine Vantomme Institute for Complex Molecular systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven school of Chemistry and RNA Institute University of New South WalesSydneyNew South Wales 2052

synthetic molecules that form functional noncovalent assemblies in water have received much attention for their potential applications as *** this work,we introduce a novel water-compatible monomer based on the phthalhydrazide moiety that assembles into hydrogen-bonded trimeric *** bulk,the material exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated temperatures,morphologically distinct from the crystalline lamellar *** water,these molecules effectively form cylinders in a one-dimensional fashion,yielding fibrous *** formation of these supramolecular polymers follows a cooperative mechanism,as evidenced by denaturation *** trimerized pattern represents a new category of aqueous su pramolecular polymers with future prospects for functional complex molecular systems.

关键词： noncovalent chemistry supramolecular polymers hydrogen bonding cooperativity nanostructure

synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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high Power Laser science and engineering 2024年第1期12卷 99-107页

作者： j.hornung Y.Zobus h.Lorenté C.Brabetz B.Zielbauer V.Bagnoud GsI helmholtzzentrum für schwerionenforschung Gmbh DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PheLIX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

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

The CCD instrument background of the sMILe sXI

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earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.j.hubbard O.hetherington D.j.hall T.W.Buggey s.Parsons T.Arnold A.holland C.Pagani s.sembay Centre for electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

The esA and CAs sMILe mission orbit is highly elliptical and will pass through multiple radiation *** soft X-ray Imager(sXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the sXI were evaluated for the two *** to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

error field penetration in j-TeXT tokamak based on two-fluid drift-MhD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TeXT team state Key Laboratory of Advanced electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MhD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MhD model error field penetration

A detailed comparison of the composition of(Re)-Ba-Cu-O-Ag bulk superconductors

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superconductivity 2024年第1期9卷 87-94页

作者： j.V.j.Congreve Y.shi A.R.Dennis h.Druiff N.C.Tutt D.A.Cardwell j.h.Durrell Department of engineering University of CambridgeCambridgeUK

The homogeneity of the microstructure and composition are critical in determining the properties of rare earthbarium‐cuprate,single grain bulk superconductors[(Re)BCO].The magnitude of the trapped magnetic field achieveable in these technologically important materials,in particular,is influenced heavily by the size and distribution of(Re)_(2)BaCuO_(x)(Re‐211)flux pinning inclusions in the bulk microstructure,whereas the size and distribution of silver agglomerates present within the bulk superconducting matrix correlate directly with improved mechanical *** careful engineering,these materials have significant potential for application in range of devices related to energy storage,medicine,electro‐magnetic machinery and microelectronic *** of(Re)BCO bulk superconductors typically involves heating a powder compact above its peritectic decomposition temperature followed by slow cooling to facilitate the growth of a single ***(Re)BCO composition has a different peritectic temperature and growth rate,which,therefore,necessitates different requirements in the heating *** fabrication temperature and growth rate,for example,may have an effect on the Re‐211 and silver distribution,which may,in turn,affect the superconducting properties of the resulting single *** this work we compare the distributions of silver and Re‐211 in the single grain microstructures of YBCOAg,GdBCO‐Ag,euBCO‐Ag and smBCO‐Ag bulk superconductors using optical microscopy,scanning electron microscopy and energy dispersive X‐ray *** observe that the distributions are very similar along both the a/b‐axis and c‐axis of these *** suggests that factors other than the maximum temperature used to achieve peritectic decomposition and the rate of single grain growth are particularly influential in determining the properties of the as‐processed samples in the top seeded melt growth *** observation demonstrates there is freedom to us

关键词： YBCO‐Ag GdBCO‐Ag smBCO‐Ag euBCO‐Ag Composition Bulk superconductor

effects of pyrethroid and organophosphate insecticides on reared black soldier fly larvae(hermetia illucens)

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Insect science 2024年第3期31卷 817-834页

作者： Nathan Meijer Lisa Zoet Theo de Rijk Paul Zomer Deborah Rjkers h.j.van der Fels-Klerx joop j.A.van Loon Wageningen Food safety Research(WFsR) Part of Wageningen University and ResearchWageningenThe Netherlands Bestico B.V. Industrieweg 6Berkel en RodenrjsThe Netherlands Plant sciences Group Laboratory of EntomologyWageningen UniversityWageningenTheNetherlands

Black soldier fly larvae(hermetia illucens)receive growing interest as a potential alternative animal feed *** insects may be exposed to insecticide residues in the rearing *** study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'*** toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CeD10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were *** addition of PBO to cypermethrin enhanced its relative potency with a factor *** data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in *** to multiple substances at lower concentrations resulted in negative additive and synergistic *** the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/*** results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of *** of organophosphates was overall low(ed from 8%to 75%for *** to very low limits in insect biomass(~0.01 mg/kg),high transfer may result in *** is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.

关键词： feed insects pesticides rearing substrate